15,491 results on '"LPS"'
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2. Anaerobic Exercise and Mental Acuity
- Published
- 2024
3. PPAR beta/delta regulates the immune response mechanisms in the porcine endometrium during LPS-induced inflammation – An in vitro study.
- Author
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Golubska, Monika, Paukszto, Łukasz, Kurzyńska, Aleksandra, Mierzejewski, Karol, Gerwel, Zuzanna, and Bogacka, Iwona
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PEROXISOME proliferator-activated receptors , *ENDOMETRIUM , *ESTRUS , *LIGANDS (Biochemistry) , *GENITALIA , *IMMUNE response , *CATTLE fertility - Abstract
Inflammation in the reproductive tract has become a serious threat to animal fertility. Recently, the role of peroxisome proliferator-activated receptor gamma (PPARγ) in the context of reproduction and the inflammatory response has been highlighted, but the role of PPARβ/δ has not been fully elucidated. The aim of the present study was to investigate the in vitro effect of PPARβ/δ ligands (agonist: L-165,041 and antagonist: GSK 3787) on the transcriptome profile of porcine endometrium during LPS-induced inflammation in the mid-luteal and follicular phases of the oestrous cycle (days 10–12 and 18–20, respectively) using the RNA-Seq method. During the mid-luteal phase of the oestrous cycle, the current study identified 145 and 143 differentially expressed genes (DEGs) after treatment with an agonist or antagonist, respectively. During the follicular phase of the oestrous cycle, 55 and 207 DEGs were detected after treatment with an agonist or antagonist, respectively. The detected DEGs are engaged in the regulation of various processes, such as the complement and coagulation cascade, NF-κB signalling pathway, or the pathway of 15-eicosatetraenoic acid derivatives synthesis. The results of the current study indicate that PPARβ/δ ligands are involved in the control of the endometrial inflammatory response. • PPARβ/δ ligands are involved in the control of the inflammatory response in the porcine endometrium. • PPARβ/δ ligands may regulate the endometrial inflammatory response by engaging multiple intracellular mechanisms. • Effects of PPARβ/δ ligands on the transcriptome of LPS-stimulated endometrium depends on the phase of the oestrous cycle. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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4. RIPK1 inhibition mitigates neuroinflammation and rescues depressive-like behaviors in a mouse model of LPS-induced depression.
- Author
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Gong, Qichao, Ali, Tahir, Hu, Yue, Gao, Ruyan, Mou, Shengnan, Luo, Yanhua, Yang, Canyu, Li, Axiang, Li, Tao, Hao, Liang Liang, He, Liufang, Yu, Xiaoming, and Li, Shupeng
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ENCEPHALITIS , *NEUROPLASTICITY , *MENTAL depression , *LABORATORY mice , *RESEARCH personnel - Abstract
Background: Depression is often linked to inflammation in the brain. Researchers have been exploring ways to reduce this inflammation to improve depression symptoms. One potential target is a protein called RIPK1, which is known to contribute to brain inflammation. However, it's unclear how RIPK1 influences depression. Our study aims to determine whether RIPK1 inhibition could alleviate neuroinflammation-associated depression and elucidate its underlying mechanisms. Methods: To investigate our research objectives, we established a neuroinflammation mouse model by administering LPS. Behavioral and biochemical assessments were conducted on these mice. The findings were subsequently validated through in vitro experiments. Results: Using LPS-induced depression models, we investigated RIPK1's role, observing depressive-like behaviors accompanied by elevated cytokines, IBA-1, GFAP levels, and increased inflammatory signaling molecules and NO/H2O2. Remarkably, Necrostatin (Nec-1 S), a RIPK1 inhibitor, mitigated these changes. We further found altered expression and phosphorylation of eIF4E, PI3K/AKT/mTOR, and synaptic proteins in hippocampal tissues, BV2, and N2a cells post-LPS treatment, which Nec-1 S also ameliorated. Importantly, eIF4E inhibition reversed some of the beneficial effects of Nec-1 S, suggesting a complex interaction between RIPK1 and eIF4E in LPS-induced neuroinflammation. Moreover, citronellol, a RIPK1 agonist, significantly altered eIF4E phosphorylation, indicating RIPK1's potential upstream regulatory role in eIF4E and its contribution to neuroinflammation-associated depression. Conclusion: These findings propose RIPK1 as a pivotal mediator in regulating neuroinflammation and neural plasticity, highlighting its significance as a potential therapeutic target for depression. [ABSTRACT FROM AUTHOR]
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- 2024
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5. 1,25-Dihydroxyvitamin D3 reduces early mortality post severe burn injury via alleviating endotoxemia, oxidative stress and inflammation.
- Author
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Chen, Yu, Guo, Jing Hui, Chen, Ya Jie, Huang, Yong, Zhang, Cheng, Zhang, Qiong, Gong, Ya Li, and Chen, Jing
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CALCITRIOL , *SUPEROXIDE dismutase , *PNEUMONIA , *OXIDATIVE stress , *EPITHELIAL cells - Abstract
Severe burn patients frequently suffer from 1,25-Dihydroxyvitamin D3 (1,25-[OH]2-D3) deficiency. In this study, we investigated the effect of 1,25-[OH]2-D3 on early mortality post severe burn and potential underlying mechanisms. Our results indicate that 1,25-[OH]2-D3 significantly reduced early mortality in mice post severe burn injury. A decrease in serum lipopolysaccharide levels and an increase in serum superoxide dismutase activity were found after administration of 1,25-[OH]2-D3. Furthermore, 1,25-[OH]2-D3 demonstrated protective effects on both intestinal and lung histology and ameliorated lung inflammation. Its anti-inflammatory effect was further confirmed in airway epithelial cells. In conclusion, our study provides evidence that 1,25-[OH]2-D3 has a significant impact on the reduction of early mortality post severe burn injury, possibly through its ability to alleviate endotoxemia, oxidative stress, and inflammation. Our findings highlight the potential of 1,25-[OH]2-D3 to protect the intestinal mucosal barrier in the early stage following major burn injury and opens up new avenues for clinical application of 1,25-[OH]2-D3 in burn patients. [Display omitted] ● 1,25-dihydroxyvitamin D3 significantly reduced early mortality in mice post severe burn injury.1,25-[OH]2-D3 markedly reduced early mortality in mice post severe burn injury. ● A decrease in serum lipopolysaccharide levels and an increase in serum superoxide dismutase activity were found after administration of 1,25-dihydroxyvitamin D3. 1,25-[OH]2-D3 markedly reduced early mortality in mice post severe burn injury. ● 1,25-dihydroxyvitamin D3 demonstrated protective effects on both intestinal and lung histology and ameliorated lung inflammation. 1,25-[OH]2-D3 had protective effects on both intestinal and lung histology and ameliorated lung inflammation. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Oxycodone attenuates lipopolysaccharide‐induced myocardial injury by inhibiting inflammation, oxidation and pyroptosis via Nrf2/HO‐1 signalling pathway.
- Author
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Wang, Yanting, Feng, Wei, Li, Shaona, Liu, Cuicui, Jia, Lili, Wang, Pei, Li, Linlin, Du, Hongyin, and Yu, Wenli
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MYOCARDIAL injury , *CREATINE kinase , *TROPONIN I , *CELLULAR signal transduction , *CARDIOVASCULAR diseases - Abstract
Myocardial injury and cardiovascular dysfunction are the most common complications of sepsis, and effective therapeutic candidate is still lacking. This study aims to investigate the protective effect of oxycodone in myocardial injury of lipopolysaccharide‐induced sepsis and its related signalling pathways. Wild‐type and nuclear factor erythroid 2‐related factor 2 (Nrf2)‐knockout mice, as well as H9c2 cardiomyocytes cultures treated with lipopolysaccharide (LPS) were used as models of septic myocardial injury. H9c2 cardiomyocytes culture showed that oxycodone protected cells from pyroptosis induced by LPS. Mice model confirmed that oxycodone pretreatment significantly attenuated myocardial pathological damage and improved cardiac function demonstrated by increased ejection fraction (EF) and fractional shortening (FS), as well as decreased cardiac troponin I (cTnI) and creatine kinase isoenzymes MB (CK‐MB). Oxycodone also reduced the levels of inflammatory factors and oxidative stress damage induced by LPS, which involves pyroptosis‐related proteins including: Nod‐like receptor protein 3 (NLRP3), Caspase 1, Apoptosis‐associated speck‐like protein contain a CARD (ASC), and Gasdermin D (GSDMD). These changes were mediated by Nrf2 and heme oxygenase‐1 (HO‐1) because Nrf2‐knockout mice or Nrf2 knockdown in H9c2 cells significantly reversed the beneficial effect of oxycodone on oxidative stress, inflammatory responses and NLRP3‐mediated pyroptosis. Our findings yielded that oxycodone therapy reduces LPS‐induced myocardial injury by suppressing NLRP3‐mediated pyroptosis via the Nrf2/HO‐1 signalling pathway in vivo and in vitro. [ABSTRACT FROM AUTHOR]
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- 2024
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7. The Synergistic Effect Study of Lipopolysaccharide (LPS) and A53T-α-Synuclein: Intranasal LPS Exposure on the A53T-α-Synuclein Transgenic Mouse Model of Parkinson's Disease.
- Author
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He, Qing, Zhang, Shuzhen, Wang, Jian, Ma, Tengfei, Ma, Ding, Wu, Li, Zhou, Mengxi, Zhao, Lei, Chen, Yajing, Liu, Jianren, and Chen, Wei
- Abstract
Aging and interactions between genetic and environmental factors are believed to be involved the chronic development of Parkinson's disease (PD). Among PD patients, abnormally aggregated α-synuclein is a major component of the Lewy body. Generally, the intranasal route is believed to be a gate way to the brain, and it assists environmental neurotoxins in entering the brain and is related to anosmia during early PD. The current study applies the chronic intranasal application of lipopolysaccharides (LPS) in 4-, 8-, 12- and 16-month-old A53T-α-synuclein (A53T-α-Syn) transgenic C57BL/6 mice at 2-day intervals for a 2-month period, for evaluating the behavioral, pathological, and biochemical changes and microglial activation in these animals. According to our results, after intranasal administration of LPS, A53T-α-Syn mice showed severe progressive anosmia, hypokinesia, selective dopaminergic (DAergic) neuronal losses, decreased striatal dopamine (DA) level, and enhanced α-synuclein accumulation within the substantia nigra (SN) in an age-dependent way. In addition, we found obvious NF-кB activation, Nurr1 inhibition, IL-1β, and TNF-α generation within the microglia of the SN. Conversely, the wild-type (WT) mice showed mild, whereas A53T-α-Syn mice had moderate PD-like changes among the old mice. This study demonstrated the synergistic effect of intranasal LPS and α-synuclein burden on PD development. Its underlying mechanism may be associated with Nurr1 inhibition within microglia and the amplification of CNS neuroinflammation. The mice with multiple factors, including aging, neuroinflammation, and α-synuclein mutation, have played a significant role in enhancing our understanding of how inflammation and α-synuclein mutation contribute to the neurodegeneration observed in PD. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Janus Kinase Inhibitor Brepocitinib Rescues Myelin Phagocytosis Under Inflammatory Conditions: In Vitro Evidence from Microglia and Macrophage Cell Lines.
- Author
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Romero-Ramírez, Lorenzo, García-Rama, Concepción, and Mey, Jörg
- Abstract
Central nervous system (CNS) injuries induce cell death and consequently the release of myelin and other cellular debris. Microglia as well as hematogenous macrophages actively collaborate to phagocyte them and undergo their degradation. However, myelin accumulation persists in the lesion site long after the injury with detrimental effects on axonal regeneration. This might be due to the presence of inhibitors of phagocytosis in the injury site. As we recently published that some proinflammatory stimuli, like interferon-γ (IFNγ) and lipopolysaccharide (LPS), inhibit myelin phagocytosis in macrophages, we have now studied the signaling pathways involved. A phagocytosis assay in Raw264.7 macrophages and N13 microglia cell lines with labeled myelin was developed with the pHrodo reagent that emits fluorescence in acidic cellular compartments (e.g.lysosomes). Pharmacological inhibition of Janus kinases (Jak) with Brepocitinib restored myelin phagocytosis and rescued the expression of genes related to phagocytosis, like triggering receptor expressed on myeloid cells 2 (TREM2), induced by IFNγ or LPS. In addition, while pharmacological inhibition of the signal transducer and activator of transcription 3 (STAT3) rescued myelin phagocytosis and the expression of phagocytosis related genes in the presence of LPS, it did not have any effect on IFNγ-treated cells. Our results show that Jak pathways participate in the inhibition of myelin phagocytosis by IFNγ and LPS. They also indicate that the resolution of inflammation is important for the clearance of cellular debris by macrophages and subsequent regenerative processes. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Validity and reliability of 10 Hz GPS sensor for measuring distance and maximal speed in soccer: Possible differences of unit positioning.
- Author
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Akyildiz, Zeki, Alvurdu, Sumer, Ceylan, Halil Ibrahim, and Clemente, Filipe Manuel
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BODY sensor networks ,GLOBAL Positioning System ,ATHLETIC ability testing ,SOCCER players ,RUNNING - Abstract
In contemporary research literature, inconsistencies regarding the validity and reliability of different brands of global positioning systems (GPSs) have been reported regarding the positioning of GPS units on athletes. For this reason, the present work investigates the validity and reliability of the measurements of GPS units placed at different locations. Thirty-two amateur soccer players (age: 21.18 ± 3.16 years; height: 175 ± 8.03 cm; body mass: 74.21 ± 4.85 kg) voluntarily participated in the current study. Participants were asked to complete a team sport simulation cycle (TSSC). During the tests, two GPS units were placed between the shoulder blades and on the chest of each athlete. Data from Polar Team Pro GPS units at both locations on the body, previously measured test area distance, and a radar gun (the gold standard) were compared to determine validity. The reliability of GPS units in measuring maximum speed is moderate (CV = 9.77–9.08, ICC = 0.23). The reliability of GPS units in measuring total distance is good (CV = 4.43–9.39, ICC = 0.15). The reliability of GPS units in measuring distance covered is poor (CV = 17.51–35.37). The measurements of total distance covered, and maximum speed recorded by the chest and back GPS units are not valid (Max speed = GPS chest-radar gun; R
2 = 0.075, GPS back-radar gun; R2 = 0.106, total distance = GPS chest-1200 m; R2 = 0.003, GPS back-1200 m; R2 = 0.097). Consequently, it can be said that 10-Hz Polar GPS sensors have good reliability for measuring total distance when placed on the chest and moderate reliability for measuring peak speed when placed on the chest and back; however, they have poor reliability at both positions for evaluating distances at different running speeds. [ABSTRACT FROM AUTHOR]- Published
- 2024
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10. The potential therapeutic role of itaconate and mesaconate on the detrimental effects of LPS-induced neuroinflammation in the brain.
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Ohm, Melanie, Hosseini, Shirin, Lonnemann, Niklas, He, Wei, More, Tushar, Goldmann, Oliver, Medina, Eva, Hiller, Karsten, and Korte, Martin
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PARKINSON'S disease , *ALZHEIMER'S disease , *INFLAMMATION , *SEPTIC shock , *CENTRAL nervous system , *PSYCHONEUROIMMUNOLOGY - Abstract
Despite advances in antimicrobial and anti-inflammatory treatment, inflammation and its consequences remain a major challenge in the field of medicine. Inflammatory reactions can lead to life-threatening conditions such as septic shock, while chronic inflammation has the potential to worsen the condition of body tissues and ultimately lead to significant impairment of their functionality. Although the central nervous system has long been considered immune privileged to peripheral immune responses, recent research has shown that strong immune responses in the periphery also affect the brain, leading to reactive microglia, which belong to the innate immune system and reside in the brain, and neuroinflammation. The inflammatory response is primarily a protective mechanism to defend against pathogens and tissue damage. However, excessive and chronic inflammation can have negative effects on neuronal structure and function. Neuroinflammation underlies the pathogenesis of many neurological and neurodegenerative diseases and can accelerate their progression. Consequently, targeting inflammatory signaling pathways offers potential therapeutic strategies for various neuropathological conditions, particularly Parkinson's and Alzheimer's disease, by curbing inflammation. Here the blood–brain barrier is a major hurdle for potential therapeutic strategies, therefore it would be highly advantageous to foster and utilize brain innate anti-inflammatory mechanisms. The tricarboxylic acid cycle-derived metabolite itaconate is highly upregulated in activated macrophages and has been shown to act as an immunomodulator with anti-inflammatory and antimicrobial functions. Mesaconate, an isomer of itaconate, similarly reduces the inflammatory response in macrophages. Nevertheless, most studies have focused on its esterified forms and its peripheral effects, while its influence on the CNS remained largely unexplored. Therefore, this study investigated the immunomodulatory and therapeutic potential of endogenously synthesized itaconate and its isomer mesaconate in lipopolysaccharide (LPS)-induced neuroinflammatory processes. Our results show that both itaconate and mesaconate reduce LPS-induced neuroinflammation, as evidenced by lower levels of inflammatory mediators, reduced microglial reactivity and a rescue of synaptic plasticity, the cellular correlate of learning and memory processes in the brain. Overall, this study emphasizes that both itaconate and mesaconate have therapeutic potential for neuroinflammatory processes in the brain and are of remarkable importance due to their endogenous origin and production, which usually leads to high tolerance. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Origin recognition complex subunit 6 (ORC6) is a key mediator of LPS-induced NFκB activation and the pro-inflammatory response.
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Xie, Zichen, Lu, Haisu, Zheng, Jiayi, Song, Jianfeng, and Sun, Keyu
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MONONUCLEAR leukocytes , *TUMOR necrosis factors , *NF-kappa B , *SEPTIC shock , *DOUBLE-stranded RNA - Abstract
Lipopolysaccharide (LPS)-activated pro-inflammatory responses play a critical role in sepsis, a life-threatening condition. This study investigates the role of origin recognition complex subunit 6 (ORC6) in LPS responses in macrophages and monocytes. Silencing ORC6 using targeted shRNA significantly reduced LPS-induced expression and production of IL-1β (interleukin-1 beta), TNF-α (tumor necrosis factor alpha), and IL-6 (interleukin-6) in THP-1 human macrophages, peripheral blood mononuclear cells (PBMCs), and bone marrow-derived macrophages (BMDMs). Additionally, ORC6 knockout (KO) via the CRISPR/Cas9 method in THP-1 macrophages inhibited LPS-induced pro-inflammatory responses, while ectopic overexpression of ORC6 enhanced LPS-induced expression and production of pro-inflammatory cytokines. ORC6 is crucial for the activation of the nuclear factor kappa B (NFκB) signaling cascade in macrophages and monocytes. LPS-induced NFκB activation was largely inhibited by ORC6 silencing or KO, but potentiated following ORC6 overexpression. Mechanistically, ORC6 associated with nuclear p65 after LPS stimulation, an interaction necessary for NFκB activation. Overexpression of ORC6 did not recover the reduced pro-inflammatory response to LPS in THP-1 macrophages with silenced p65. Furthermore, the NFκB inhibitor BMS-345,541 nearly eliminated the pro-inflammatory response enhanced by ORC6 overexpression in response to LPS. Further studies revealed that ORC6 depletion inhibited NFκB activation induced by double-stranded RNA (dsRNA) and high mobility group box 1 (HMGB1) in THP-1 macrophages. In vivo experiments demonstrated that macrophage-specific knockdown of ORC6 protected mice from LPS-induced septic shock and inhibited LPS-stimulated production of IL-1β, TNF-α, and IL-6 in mouse serum. ORC6 silencing also inhibited LPS-induced NFκB activation in ex vivo cultured PBMCs following macrophage-specific knockdown of ORC6. These findings highlight ORC6 as a pivotal mediator in LPS-induced NFκB activation and the pro-inflammatory response in sepsis, suggesting that targeting ORC6 could be a novel therapeutic strategy for managing sepsis and related inflammatory conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Inhibiting CD44-ICD Attenuates LPS-Induced Initiation of Hepatic Inflammation in Septic Mice.
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Li, Li-Hsuan, Hsu, Dur-Zong, Chandrasekaran, Victor Raj Mohan, and Liu, Ming-Yie
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NITRIC-oxide synthases , *ALANINE aminotransferase , *MULTIPLE organ failure , *CD44 antigen , *INFLAMMATION , *ASPARTATE aminotransferase - Abstract
Sepsis is a severe condition induced by microbial infection. It elicits a systemic inflammatory response, leading to multi-organ failure, and the liver, as a scavenger, plays a significant role in this process. Controlling hepatic inflammation and maintaining liver function is crucial in managing sepsis. CD44-ICD, as a CD44 signal transductor, is involved in multiple inflammatory responses. However, the role of CD44-ICD in lipopolysaccharide (LPS)-induced hepatic inflammation has not been investigated. Therefore, we aimed to examine whether CD44-ICD initiates hepatic inflammation in septic mice. We induced hepatic inflammation in mice by administering LPS. DAPT, a CD44-ICD inhibitor, was given to mice or Chang cells 30 min or 1 h before LPS administration (10 mg/kg, i.p., or 100 ng/mL, respectively). Inhibition of CD44-ICD decreased the level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatic necrosis, inflammatory cell infiltration, interleukin (IL)-1β, inducible NO synthase (iNOS), nitric oxide (NO) production, nuclear factor (NF)κB signaling pathway proteins, and CD44 expression in mice. CD44-ICD inhibition also decreased IL-1β and CD44 expression levels in Chang cells. CD44-ICD may be a primary regulatory function in CD44-associated LPS-induced initiation of hepatic inflammation in mice. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Anti-Neuroinflammatory Effect of Ombuin from Rhamnus erythroxylon Pall. Leaves in LPS-Induced BV-2 Microglia by Targeting Src and Suppressing the PI3K-AKT/NF-κB Signaling Pathway.
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Bian, Yanjie, Qiao, Nan, Han, Suyun, Gao, Jixiang, Lv, Xiaofang, Yuan, Lihuan, Zhang, Linjing, and Wei, Zuofu
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WESTERN immunoblotting , *REACTIVE oxygen species , *MOLECULAR docking , *TRANSCRIPTOMES , *HEAT transfer - Abstract
The leaves of Rhamnus erythroxylon Pall. are widely used as tea substitutes in northwest China for their fragrant aroma, anti-irritability, and digestion-enhancing properties. Ombuin, a main flavonoid compound found in the leaves, exhibited notable anti-inflammatory and antioxidant effects. However, its potential role in treating neuroinflammatory-related diseases remains unexplored. Thus, this study aims to evaluate the anti-neuroinflammatory effects of ombuin and to explore the underlying molecular mechanisms. According to our findings, ombuin dramatically reduced the release of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), IL-1β, nitric oxide (NO), and reactive oxygen species (ROS) in lipopolysaccharide (LPS)-stimulated BV-2 microglia. Further analysis, including transcriptomics, network pharmacology, molecular docking, and cellular heat transfer assays, revealed that Src was a direct target of ombuin. Western blot analysis showed that ombuin effectively suppressed Src phosphorylation and inhibited the downstream expressions of p-PI3K p85, p-AKT1, p-IKKα/β, p-IκBα, and nuclear factor κB (NF-κB). Meanwhile, the repression of Src significantly reversed the anti-neuroinflammatory activity of ombuin. Our results identified Src as a direct target of ombuin and implied that ombuin exerted an anti-neuroinflammatory effect by inhibiting Src phosphorylation and suppressing the activation of the PI3K-AKT and NF-κB pathways, which might provide an alternative therapeutic strategy for neurodegenerative diseases. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Xanthoxylin Attenuates Lipopolysaccharide-Induced Lung Injury through Modulation of Akt/HIF-1α/NF-κB and Nrf2 Pathways.
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Liu, Fu-Chao, Yang, Yuan-Han, Liao, Chia-Chih, and Lee, Hung-Chen
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NUCLEAR factor E2 related factor , *TUMOR necrosis factors , *ADULT respiratory distress syndrome , *PROTEIN kinase B , *BIOACTIVE compounds - Abstract
Xanthoxylin, a bioactive phenolic compound extracted from the traditional herbal medicine Penthorum Chinense Pursh, is renowned for its anti-inflammatory effects. While previous studies have highlighted the anti-inflammatory and antioxidant properties of Xanthoxylin, its precise mechanisms, particularly concerning immune response and organ protection, remain underexplored. This study aimed to elucidate the effects of Xanthoxylin on inflammation and associated signaling pathways in a mouse model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). ALI was induced via intratracheal administration of LPS, followed by intraperitoneal injections of Xanthoxylin at doses of 1, 2.5, 5, and 10 mg/kg, administered 30 min post-LPS exposure. Lung tissues were harvested for analysis 6 h after LPS challenge. Xanthoxylin treatment significantly mitigated lung tissue damage, pathological alterations, immune cell infiltration, and the production of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). Additionally, Xanthoxylin modulated the expression of key proteins in the protein kinase B (Akt)/hypoxia-inducible factor 1-alpha (HIF-1α)/nuclear factor-kappa B (NF-κB) signaling pathway, as well as nuclear factor erythroid 2-related factor 2 (Nrf2) and oxidative markers such as superoxide dismutase (SOD) and malondialdehyde (MDA) in the context of LPS-induced injury. This study demonstrates that Xanthoxylin exerts protective and anti-inflammatory effects by down-regulating and inhibiting the Akt/HIF-1α/NF-κB pathways, suggesting its potential as a therapeutic target for the prevention and treatment of ALI or acute respiratory distress syndrome (ARDS). [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. Exosomes derived from endothelial progenitor cells ameliorate LPS-induced brain microvascular endothelial cells injury by delivering miR-126a-5p.
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Zhang, Hongquan, Lu, Caiyun, Wu, Lili, Li, Jiang, Huang, Min, Tao, Xingyu, Wu, Yuanbo, and Jia, Baohui
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VASCULAR endothelial cells , *PROGENITOR cells , *ENDOTHELIAL cells , *WESTERN immunoblotting , *TRANSMISSION electron microscopy - Abstract
Endothelial progenitor cells (EPCs) play a crucial role in maintaining vascular health and aiding in the repair of damaged blood vessels. However, the specific impact of EPCs-derived exosomes on vascular endothelial cell injury caused by lipopolysaccharide (LPS) remains inadequately understood. This study aims to explore the potential benefits of EPC-exosomes in mitigating LPS-induced vascular injury and to elucidate the underlying mechanism. Initially, EPCs were isolated from mouse peripheral blood, and their identity was confirmed through flow cytometry and immunocytochemistry. Subsequently, the exosomes derived from EPCs were identified using transmission electron microscopy (TEM) and western blot analysis. A sepsis model was induced by subjecting brain microvascular endothelial cells (BMECs) to LPS-induced injury. Both EPC and their exosomes demonstrated a significant increase in BMECs proliferation, reduced apoptosis, decreased levels of pro-inflammatory factors (TNF-α, IL-6, and caspase-3), and enhanced sprouting and angiogenesis of BMECs. Notable, the Exosomes demonstrated a more pronounced impact on these parameters. Furthermore, both EPCs and Exosomes exhibited significantly increased levels of miR-126a-5p, with the Exosomes showing a more substantial enhancement. These findings suggest that supplementing exosomal miR-126a-5p from EPCs can provide protective effects on BMECs, offering a potential therapeutic option for treating sepsis-induced microvascular endothelial cell injury. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. Revisiting the role of hypoxia-inducible factors and nuclear factor erythroid 2-related factor 2 in regulating macrophage inflammation and metabolism.
- Author
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Ting, Kenneth K. Y.
- Subjects
NUCLEAR factor E2 related factor ,HYPOXIA-inducible factors ,MYELOID cells ,TRANSCRIPTION factors ,IMMUNE response ,GLYCOLYSIS - Abstract
The recent birth of the immunometabolism field has comprehensively demonstrated how the rewiring of intracellular metabolism is critical for supporting the effector functions of many immune cell types, such as myeloid cells. Among all, the transcriptional regulation mediated by Hypoxia-Inducible Factors (HIFs) and Nuclear factor erythroid 2-related factor 2 (NRF2) have been consistently shown to play critical roles in regulating the glycolytic metabolism, redox homeostasis and inflammatory responses of macrophages (Mjs). Although both of these transcription factors were first discovered back in the 1990s, new advances in understanding their function and regulations have been continuously made in the context of immunometabolism. Therefore, this review attempts to summarize the traditionally and newly identified functions of these transcription factors, including their roles in orchestrating the key events that take place during glycolytic reprogramming in activated myeloid cells, as well as their roles in mediating Mj inflammatory responses in various bacterial infection models. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Increasing the complexity of lipoprotein characterization for cardiovascular risk in type 2 diabetes.
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Guardiola, Montse, Rehues, Pere, Amigó, Núria, Arrieta, Francisco, Botana, Manuel, Gimeno‐Orna, José A., Girona, Josefa, Martínez‐Montoro, José Ignacio, Ortega, Emilio, Pérez‐Pérez, Antonio, Sánchez‐Margalet, Víctor, Pedro‐Botet, Juan, Ribalta, Josep, Aguilar Diosdado, Manuel, Arrieta, Francisco J., Becerra Fernández, Antonio, Botana López, Manuel Antonio, Campos Pastor, María del Mar, Durán García, Santiago, and Fornos Pérez, José Antonio
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TYPE 2 diabetes , *DYSLIPIDEMIA , *CARDIOVASCULAR diseases risk factors , *LDL cholesterol , *HDL cholesterol , *NUCLEAR magnetic resonance - Abstract
The burden of cardiovascular disease is particularly high among individuals with diabetes, even when LDL cholesterol is normal or within the therapeutic target. Despite this, cholesterol accumulates in their arteries, in part, due to persistent atherogenic dyslipidaemia characterized by elevated triglycerides, remnant cholesterol, smaller LDL particles and reduced HDL cholesterol. The causal link between dyslipidaemia and atherosclerosis in T2DM is complex, and our contention is that a deeper understanding of lipoprotein composition and functionality, the vehicle that delivers cholesterol to the artery, will provide insight for improving our understanding of the hidden cardiovascular risk of diabetes. This narrative review covers three levels of complexity in lipoprotein characterization: 1—the information provided by routine clinical biochemistry, 2—advanced nuclear magnetic resonance (NMR)‐based lipoprotein profiling and 3—the identification of minor components or physical properties of lipoproteins that can help explain arterial accumulation in individuals with normal LDLc levels, which is typically the case in individuals with T2DM. This document highlights the importance of incorporating these three layers of lipoprotein‐related information into population‐based studies on ASCVD in T2DM. Such an attempt should inevitably run in parallel with biotechnological solutions that allow large‐scale determination of these sets of methodologically diverse parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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18. FXR deletion attenuates intestinal barrier dysfunction in murine acute intestinal inflammation.
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O’Guinn, MaKayla L., Handler, David A., Hsieh, Jonathan J., Mallicote, Michael U., Feliciano, Karina, and Gayer, Christopher P.
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FARNESOID X receptor , *INFLAMMATORY bowel diseases , *INTESTINES , *INFLAMMATION , *INTESTINAL diseases - Abstract
Accumulating literature suggests that the farnesoid-X receptor (FXR), a nuclear bile acid receptor best known for its role in bile acid homeostasis, is also a potent context-dependent regulator of inflammation. FXR may thus be relevant to several intestinal disease states including inflammatory bowel disease, necrotizing enterocolitis, and sepsis. In this study, we tested the effects of FXR deletion on acute murine intestinal inflammation. We found that FXR knockout (KO) mice were protected from intestinal injury and barrier dysfunction induced by lipopolysaccharide (LPS) injection, dithizone (DI)/Klebsiella, and cecal ligation/puncture models. In the LPS model, RNA sequencing and qPCR analysis showed that this protection correlated with substantial reduction in LPSinduced proinflammatory gene expression, including lower tissue levels of Il1a, Il1b, and Tnf. Examining functional effects on the epithelium, we found that LPS-induced tight junctional disruption as assessed by internalization of ZO-1 and occludin was ameliorated in FXR KO animals. Taken together, these data suggest a role for FXR in the intestinal barrier during inflammatory injury. NEW & NOTEWORTHY Intestinal barrier failure is a hallmark in gut-origin sepsis. We demonstrate that the intestinal barriers of farnesoid-X receptor (FXR) knockout (KO) animals are protected from inflammatory insult using multiple models of acute intestinal inflammation. This protection is due to decreased inflammatory cytokine production and maintenance of tight junctional architecture seen within the KO animals. This is the first report of FXR deletion being protective to the intestinal barrier. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Anti-inflammatory effect of proanthocyanidins from blueberry through NF-κβ/NLRP3 signaling pathway in vivo and in vitro.
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Liu, Xinyao, Zang, Lulu, Yu, Jiabao, Yu, Jinjin, Wang, Siqi, Zhou, Lili, Song, Huixin, Ma, Yajing, Niu, Xiaofeng, and Li, Weifeng
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SEPTIC shock , *SYSTEMIC inflammatory response syndrome , *WESTERN immunoblotting , *HEMATOXYLIN & eosin staining , *CELLULAR signal transduction , *ENDOTOXINS - Abstract
Systemic inflammatory response syndrome (SIRS) is an uncontrolled systemic inflammatory response. Proanthocyanidins (PC) is a general term of polyphenol compounds widely existed in blueberry fruits and can treat inflammation-related diseases. This study aimed to explore the regulatory effect of PC on lipopolysaccharide (LPS)-induced systemic inflammation and its potential mechanism, providing effective strategies for the further development of PC. Here, RAW264.7 macrophages were stimulated with LPS to establish an inflammation model in vitro, while endotoxin shock mouse models were constructed by LPS in vivo. The function of PC was investigated by MTT, ELISA kits, H&E staining, immunohistochemistry, and Western blot analysis. Functionally, PC could demonstrate the potential to mitigate mortality in mice with endotoxin shock, as well as attenuated the levels of inflammatory cytokines (IL-6, TNF-α) and biochemical indicators (AST, ALT, CRE and BUN). Moreover, it had a significant protective effect on lung and kidney tissues damage. Mechanistically, PC exerted anti-inflammatory effects by inhibiting the activation of the NF-κB/NLRP3 signaling pathway. PC might have the potential ability of anti-inflammatory effects via modulation of the NF-κB/NLRP3 signaling pathway. [ABSTRACT FROM AUTHOR]
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- 2024
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20. NP-12 peptide functionalized nanoparticles counteract the effect of bacterial lipopolysaccharide on cultured osteoblasts.
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Toledano-Osorio, Manuel, de Luna-Bertos, Elvira, Toledano, Manuel, Manzano-Moreno, Francisco Javier, Ruiz, Concepción, Sanz, Mariano, and Osorio, Raquel
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PEPTIDES , *OSTEOBLASTS , *LIPOPOLYSACCHARIDES , *GENETIC overexpression , *EXTRACELLULAR matrix , *PEPTIDE antibiotics - Abstract
To evaluate whether nanoparticles (NPs) functionalized with Tideglusib (TDg, NP-12), and deposited on titanium surfaces, would counteract the effect of bacterial lipopolysaccharide (LPS) on osteoblasts. Experimental groups were: (a) Titanium discs (TiD), (b) TiD covered with undoped NPs (Un-NPs) and (c) TiD covered with TDg-doped NPs (TDg-NPs). Human primary osteoblasts were cultured onto these discs, in the presence or absence of bacterial LPS. Cell proliferation was assessed by MTT-assay and differentiation by measuring the alkaline phosphatase activity. Mineral nodule formation was assessed by the alizarin red test. Real-time quantitative polymerase chain reaction was used to study the expression of Runx-2, OSX, ALP, OSC, OPG, RANKL, Col-I, BMP-2, BMP-7, TGF-β1, VEGF, TGF-βR1, TGF-βR2, and TGF-βR3 genes. Osteoblasts morphology was studied by Scanning Electron Microscopy. One-way ANOVA or Kruskal-Wallis and Bonferroni multiple comparisons tests were carried out (p < 0.05). TDg-NPs enhanced osteoblasts proliferation. Similarly, this group increased ALP production and mineral nodules formation. TDg-NPs on titanium discs resulted in overexpression of the proliferative genes, OSC and OSX, regardless of LPS activity. In the absence of LPS, TDg-NPs up-regulated Runx2, COL-I, ALP, BMP2 and BMP7 genes. OPG/RANKL gene ratios were increased about 2500 and 4,000-fold by TDg-NPs, when LPS was added or not, respectively. In contact with the TDg-NPs osteoblasts demonstrated an elongated spindle-shaped morphology with extracellular matrix production. TDg-NPs on titanium discs counteracted the detrimental effect of LPS by preventing the decrease on osteoblasts proliferation and mineralization, and produced an overexpression of proliferative and bone-promoting genes on human primary osteoblasts. • The effect of TDg-NPs on human osteoblasts has not been previously described. • GSK-3 inhibitor is able to attenuate the LPS-inhibitory effects on osteoblasts. • TDg-NPs demonstrated osteogenic properties on osteoblasts. • NP-12 peptide could be useful in the treatment of peri-implant diseases. [ABSTRACT FROM AUTHOR]
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- 2024
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21. The Interplay of TLR-NFκB Signalling Pathway and Functional Immune-Related Enzymes in the Inflammatory Response of Ciona robusta.
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Bisanti, Luca, La Corte, Claudia, Dara, Mariano, Bertini, Federica, Vizioli, Jacopo, Parisi, Maria Giovanna, Cammarata, Matteo, and Parrinello, Daniela
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NF-kappa B , *ENZYMATIC analysis , *TOLL-like receptors , *ALKALINE phosphatase , *INFLAMMATION - Abstract
Simple Summary: Ascidians (Tunicata) are a powerful model for studying the innate immune system. To better understand the dynamics of immune responses under bacterial challenge in Ciona robusta, we exposed ascidians to lipopolysaccharide (LPS) injection. Immunohistochemistry analysis on two components of the nuclear factor kappa B (NfκB) key signalling pathway, the Toll-like receptor 4 (TLR4) and NFκB, showed their over-expression on tissue of LPS-injected ascidians. Also, several enzymes related to immune responses were up-modulated following the LPS challenge. Our study suggests a broad and complex innate immune activation in the regulation of tunicate inflammatory responses. The close phylogenetic relationship between ascidians (Tunicata) and vertebrates makes them a powerful model for studying the innate immune system. To better understand the nature and dynamics of immune responses and the mechanisms through which bacterial infections are detected and translated into inflammation in Ciona robusta, we applied an approach combining in vivo lipopolysaccharide (LPS) stimulation, immune-labelling techniques and functional enzymatic analyses. The immunohistochemistry showed that Toll-like receptor 4 (TLR4) and nuclear factor kappa B (NFκB) were expressed during the inflammatory pharynx response 4 h post-LPS, with the formation of nodules in pharynx vessel lumen. Also, the endothelium vessels were involved in the inflammatory response. Observations of histological sections from naive and buffer-inoculated ascidians confirmed an immuno-positive response. Enzyme immune parameters—which included the activity of phenoloxidase, glutathione peroxidase, lysozyme, alkaline phosphatase and esterase—showed up-modulation 4 h after LPS injection, confirming their participation during ascidian inflammatory response. These findings provide new insights into the mechanisms underlying the LPS-induced C. robusta response and suggest that a broad innate immune mechanism, as in vertebrates, is involved in the regulation of inflammatory responses. Further findings in this direction are needed to cover knowledge gaps regarding the organized set of molecular and cellular networks involved in universal immune interactions with pathogens. [ABSTRACT FROM AUTHOR]
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- 2024
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22. P53 Alleviates the Progression of Periodontitis by Reducing M1-type Macrophage Differentiation.
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Liu, Tingting, Chen, Dongru, Tang, Shanshan, Zou, Zhaolei, Yang, Fangyi, Zhang, Yutian, Wang, Dikan, Lu, Huanzi, Liao, Guiqing, and Liu, Xiangqi
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BONE resorption , *P53 antioncogene , *BONE marrow , *GENE expression , *INTRAPERITONEAL injections , *PERIODONTITIS - Abstract
Our objective is to explore the effect of P53 on the progression of periodontitis by regulating macrophages differentiation both in vitro and in vivo. Eighteen normal and periodontitis gingival tissues were collected for detecting P53 expression and macrophages infiltration by immunofluorescence, real-time PCR (qPCR) and western-blot. The differentiation and the inflammatory cytokines (TNF-α and IL-6) expression of THP-1, RAW264.7 and bone marrow derived macrophage (BMDM) cells, treating with Pifithrin-α (P53 inhibitor) or Nutlin-3a (P53 activator) under lipopolysaccharide (LPS) stimulation, were observed by flow cytometry, qPCR and ELISA. The severity of periodontitis, inflammatory cytokines expression and macrophages infiltration were measured in experimental periodontitis wild-type mice and p53 gene conditional knocked-out (p53-CKO) mice, which were established by ligation and LPS injection. A higher number of P53-positive macrophages was found infiltrated in periodontitis tissues. In vitro experiments showed that compared with Nutlin-3a, the proportion of M1-type macrophages and the expression of TNF-α and IL-6 were higher in Pifithrin-α treated cells under LPS stimulation. In vivo experimental periodontitis mice, the Pifithrin-α intraperitoneal injection group showed greater alveolar bone loss, higher levels of TNF-α and IL-6 secretion and more M1-type macrophages infiltration, while the Nutlin-3a intraperitoneal injection group were observed mild symptoms compared with mice in the periodontitis group. P53-CKO mice exhibited more severe periodontitis and more M1-type macrophages infiltrated in local tissues compared with wild-type mice. The activation of p53 gene could alleviate periodontitis by reducing M1-type macrophage polarization. P53 may serve as keeper in the progression of periodontitis, providing new insights into periodontitis treatment. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Choline chloride shows gender‐dependent positive effects on social deficits, learning/memory impairments, neuronal loss and neuroinflammation in the lipopolysaccharide‐induced rat model of autism.
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Egilmez, Cansu Bilister, Pazarlar, Burcu Azak, Erdogan, Mumin Alper, Uyanikgil, Yiğit, and Erbas, Oytun
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GLIAL fibrillary acidic protein , *LABORATORY rats , *NERVE growth factor , *OPERANT conditioning , *CHOLINE chloride - Abstract
The neuroprotective effects of choline chloride, an essential nutrient, a precursor for the acetylcholine and synthesis of membrane phospholipids, have been associated with neurological and neurodegenerative diseases. Its contribution to autism spectrum disorder, a neurodevelopmental disorder, remains unknown. Thus, we aimed to evaluate the effects of choline chloride on social behaviours, and histopathological and biochemical changes in a rat autism model. The autism model was induced by administration of 100 μg/kg lipopolysaccharide (LPS) on the 10th day of gestation. Choline chloride treatment (100 mg/kg/day) was commenced on PN5 and maintained until PN50. Social deficits were assessed by three‐chamber sociability, open field, and passive avoidance learning tests. Tumour necrosis factor alpha (TNF‐α), interleukin‐2 (IL) and IL‐17, nerve growth factor (NGF), and glutamate decarboxylase 67 (GAD67) levels were measured to assess neuroinflammatory responses. In addition, the number of hippocampal and cerebellar neurons and glial fibrillary acidic protein (GFAP) expression were evaluated. Social novelty and passive avoidance learning tests revealed significant differences in choline chloride‐treated male rats compared with saline‐treated groups. TNF‐α, IL‐2, and IL‐17 were significantly decreased after choline chloride treatment in both males and females. NGF and GAD67 levels were unchanged in females, while there were significant differences in males. Histologically, significant changes in terms of gliosis were detected in hippocampal CA1 and CA3 regions and cerebellum in choline chloride‐treated groups. The presence of ameliorative effects of choline chloride treatment on social behaviour and neuroinflammation through neuroinflammatory, neurotrophic, and neurotransmission pathways in a sex‐dependent rat model of LPS‐induced autism was demonstrated. [ABSTRACT FROM AUTHOR]
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- 2024
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24. The evaluation of cystatin protein vaccines based on the stress response of ticks triggered by low‐temperature and toxin stress in Haemaphysalis doenitzi.
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Zhang, Song‐Bo, Gao, Zhi‐Hua, Wang, Yi‐Kui, Lv, Wen‐Xia, Dong, Ke‐Xin, Guo, Fei‐Di, Wang, Run‐Ying, and Yang, Xiao‐Long
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EGG incubation ,TICKS ,AMINO acid sequence ,ENZYME-linked immunosorbent assay ,TOXINS ,TICK control ,RECOMBINANT proteins ,BACTERIAL toxins - Abstract
BACKGROUND: Ticks, which are obligate blood‐feeding parasites, transmit a wide range of pathogens during their hematophagic process. Certain enzymes and macromolecules play a crucial role in inhibition of several tick physiological processes, including digestion and reproduction. In the present study, genes encoding type 2 cystatin were cloned and characterized from Haemaphysalis doenitzi, and the potential role of cystatin in tick control was further assessed. RESULTS: Two cystatin genes, HDcyst‐1 and HDcyst‐2, were successfully cloned from the tick H. doenitzi. Their open reading frames are 390 and 426 base pairs, and the number of coding amino acids are 129 and 141, respectively. In the midgut, salivary glands, Malpighian tubules and ovaries of ticks, the relative expression of HDcyst‐1 was higher in the midgut and Malpighian tubules, and HDcyst‐2 was higher in the salivary glands of H. doenitzi, respectively. Lipopolysaccharide (LPS) injection and low‐temperature stress elevated cystatin expression in ticks. Enzyme‐linked immunosorbent assay showed that both rHDcyst‐1 and rHDcyst‐2 protein vaccines increased antibody levels in immunized rabbits. A vaccination trial in rabbits infected with H. doenitzi showed that both recombinant cystatin proteins significantly reduced tick engorgement weights and egg mass weight, in particular, rHDcyst‐1 significantly prolonged tick engorgement time by 1 day and reduced egg hatching rates by 16.9%. In total, rHDcyst‐1 and rHDcyst‐2 protein vaccinations provided 64.1% and 51.8% protection to adult female ticks, respectively. CONCLUSION: This is the first report on the immunological characterization of the cystatin protein and sequencing of the cystatin gene in H. doenitzi. Cystatin proteins are promising antigens that have the potential to be used as vaccines for infestation of H. doenitzi control. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Pseudomonas aeruginosa Lipid A Structural Variants Induce Altered Immune Responses.
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Hofstaedter, Casey E., O'Keefe, Ian P., Met, Charles M., Wu, Ling, Vanderwoude, Jelly, Shin, Sunny, Diggle, Stephen P., Riquelme, Sebastian A., Rasko, David A., Doi, Yohei, Harro, Janette M., Kopp, Benjamin T., and Ernst, Robert K.
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PSEUDOMONAS aeruginosa ,IMMUNE response ,LIPIDS ,MEMBRANE lipids ,LUNG infections ,CYSTIC fibrosis ,TOLL-like receptors - Abstract
Pseudomonas aeruginosa causes chronic lung infection in cystic fibrosis (CF), resulting in structural lung damage and progressive pulmonary decline. P. aeruginosa in the CF lung undergoes numerous changes, adapting to host-specific airway pressures while establishing chronic infection. P. aeruginosa undergoes lipid A structural modification during CF chronic infection that is not seen in any other disease state. Lipid A, the membrane anchor of LPS (i.e., endotoxin), comprises the majority of the outer membrane of Gram-negative bacteria and is a potent Toll-like receptor 4 (TLR4) agonist. The structure of P. aeruginosa lipid A is intimately linked with its recognition by TLR4 and subsequent immune response. Prior work has identified P. aeruginosa strains with altered lipid A structures that arise during chronic CF lung infection; however, the impact of the P. aeruginosa lipid A structure on airway disease has not been investigated. Here, we show that P. aeruginosa lipid A lacks PagL-mediated deacylation during human airway infection using a direct-from-sample mass spectrometry approach on human BAL fluid. This structure triggers increased proinflammatory cytokine production by primary human macrophages. Furthermore, alterations in lipid A 2-hydroxylation impact cytokine response in a site-specific manner, independent of CF transmembrane conductance regulator function. It is interesting that there is a CF-specific reduction in IL-8 secretion within the epithelial-cell compartment that only occurs in CF bronchial epithelial cells when infected with CF-adapted P. aeruginosa that lacks PagL-mediated lipid A deacylation. Taken together, we show that P. aeruginosa alters its lipid A structure during acute lung infection and that this lipid A structure induces stronger signaling through TLR4. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Cholesterol Efflux Decreases TLR4-Target Gene Expression in Cultured Macrophages Exposed to T. brucei Ghosts.
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Fernando, Lawrence, Echesabal-Chen, Jing, Miller, Murphy, Powell, Rhonda Reigers, Bruce, Terri, Paul, Apurba, Poudyal, Nava, Saliutama, Joshua, Parman, Kristina, Paul, Kimberly S., and Stamatikos, Alexis
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LIPID rafts ,LIGANDS (Biochemistry) ,AFRICAN trypanosomiasis ,TOLL-like receptors ,GENE expression - Abstract
Trypanosoma brucei causes African trypanosomiasis in humans. Infection with T. brucei elicits a potent pro-inflammatory immune response within infected human hosts, and this response is thought to at least be partially due to Toll-like receptor (TLR) activation. In response to stimulation by lipopolysaccharide and other pathogen antigens, TLR4 translocates to lipid rafts, which induces the expression of pro-inflammatory genes. However, cholesterol efflux is acknowledged as anti-inflammatory due to promoting lipid raft disruption. In this study, we wanted to assess the impact of T. brucei "ghosts", which are non-viable T. brucei essentially devoid of intracellular contents, in stimulating macrophage TLR4 translocation to lipid rafts, and whether promoting cholesterol efflux in macrophages incubated with T. brucei ghosts attenuates TLR4-target gene expression. When cultured macrophages were exposed to T. brucei ghosts, we observed an increase in lipid raft TLR4 protein content, which suggests certain surface molecules of T. brucei serve as ligands for TLR4. However, pretreating macrophages with cholesterol acceptors before T. brucei ghost exposure decreased lipid raft TLR4 protein content and the expression of pro-inflammatory TLR4-target genes. Taken together, these results imply that macrophage cholesterol efflux weakens pro-inflammatory responses which occur from T. brucei infection via increasing macrophage lipid raft disruption. [ABSTRACT FROM AUTHOR]
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- 2024
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27. Immune-enhancing neutrophils reprogrammed by subclinical low-dose endotoxin in cancer treatment.
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Zhang, Yao, Lee, Christina, Geng, Shuo, Wang, Jing, Bohara, Udipta, Hou, Jacqueline, Yi, Ziyue, and Li, Liwu
- Abstract
Despite the re-emergence of the pioneering "Coley's toxin" concept in anti-cancer immune therapies highlighted by check-point inhibitors and CAR-T approaches, fundamental mechanisms responsible for the immune-enhancing efficacy of low-dose "Coley's toxin" remain poorly understood. This study examines the novel reprogramming of immune-enhancing neutrophils by super-low dose endotoxin conducive for anti-cancer therapies. Through integrated analyses including scRNAseq and functional characterizations, we examined the efficacy of reprogrammed neutrophils in treating experimental cancer. We observed that neutrophils trained by super-low dose endotoxin adopt a potent immune-enhancing phenotype characterized by CD177
lo CD11blo CD80hi CD40hi Dectin2hi . Both murine and human neutrophils trained by super-low dose endotoxin exhibit relieved suppression of adaptive T cells as compared to un-trained neutrophils. Functionally, neutrophils trained by super-low dose endotoxin can potently reduce tumor burden when transfused into recipient tumor-bearing mice. Mechanistically, Super-low dose endotoxin enables the generation of immune-enhancing neutrophils through activating STAT5 and reducing innate suppressor IRAK-M. Together, our data clarify the long-held mystery of "Coley's toxin" in rejuvenating anti-tumor immune defense, and provide a proof-of-concept in developing innate neutrophil-based anti-tumor therapeutics. Synopsis: Neutrophils may be dynamically trained into divergent and distinct functional phenotypes, which may bear fundamental relevance in the modulation of tumor immune environment. Neutrophils trained by subclinical low-dose endotoxin (lipopolysaccharide-LPS) adopt a unique immune-enhancing and less pathogenic inflammatory state. Immune-enhancing and less pathogenic neutrophils are characterized by reduced CD11b, CD177; and elevated expression of CD40, CD80, and Ly6A/E. Neutrophils trained by low-dose LPS can alleviate immune suppression in vivo and in vitro. Transfusion of low-dose LPS trained neutrophils can relieve tissue inflammation and reduce experimental colon tumor load. Neutrophils may be dynamically trained into divergent and distinct functional phenotypes, which may bear fundamental relevance in the modulation of tumor immune environment. [ABSTRACT FROM AUTHOR]- Published
- 2024
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28. The natural sesquiterpene lactone inulicin suppresses the production of pro-inflammatory mediators via inhibiting NF-κB and AP-1 pathways in LPS-activated macrophages.
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Yan, Jingjing, Cai, Min, Zang, Chenchen, Li, Wenjing, Liu, Zhuangzhuang, Li, Ximeng, Gao, Yuan, and Qi, Yun
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PERITONEAL macrophages , *NITRIC-oxide synthases , *MACROPHAGES , *THERAPEUTICS , *PERITONEAL dialysis , *EXTRACELLULAR signal-regulated kinases , *TERPENES - Abstract
AbstractObjectiveMethodsResultsConclusionsInulicin is a sesquiterpene lactone in Inulae Flos which is clinically used for the treatment of inflammatory diseases, such as cough, sputum production, and vomiting. This study aimed to demonstrate the anti-inflammatory activity and the underlying mechanism of inulicin by using lipopolysaccharide (LPS)-induced
in vitro andin vivo models.LPS-stimulated RAW264.7 macrophages and mouse peritoneal macrophages (MPMs) were used for evaluating thein vitro anti-inflammatory activity of inulicin, while endotoxemia mice were used for evaluating itsin vivo action. Cytokines’ levels were determined by ELISA. RT-qPCR and western blot were used for assaying the mRNA and protein levels of target genes. RAW264.7 macrophages transfected with reporter plasmid pNFκB-TA-luc or pAP1-TA-luc were used for assaying the activation of NF-κB or AP-1 signaling.Inulicin significantly inhibited LPS-induced production of NO, IL-6, c-c motif chemokine ligand 2 (CCL2), and IL-1β in both RAW264.7 cells and MPMs. Mechanism study indicated that it could suppress inducible nitric oxide synthase, IL-6, CCL2, and IL-1β mRNA levels in LPS-stimulated RAW264.7 cells. Moreover, inulicin inhibited IκBα phosphorylation and prevented the nuclear translocation of p65, thereby inactivating NF-κB signaling. Concurrently, it also inhibited AP-1 signaling by reducing the phosphorylation of C-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK). In endotoxemia mice, a single intraperitoneal administration of inulicin could decrease the production of pro-inflammatory cytokines in serum and peritoneal lavage fluid.The present study demonstrates that inulicin possesses anti-inflammatory effectsin vitro andin vivo , which suggests that inulicin might be a promising candidate for the treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]- Published
- 2024
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29. Mechanistic Insights of Neuroprotective Efficacy of Verapamil-Loaded Carbon Quantum Dots against LPS-Induced Neurotoxicity in Rats.
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Mosalam, Esraa M., Elberri, Aya Ibrahim, Abdallah, Mahmoud S., Abdel-Bar, Hend Mohamed, Zidan, Abdel-Aziz A., Batakoushy, Hany A., and Abo Mansour, Hend E.
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QUANTUM dots , *LABORATORY rats , *ALZHEIMER'S disease , *P-glycoprotein , *TAU proteins , *RATS - Abstract
Alzheimer's disease (AD) is a neurodegenerative disease that badly impacts patients and their caregivers. AD is characterized by deposition of amyloid beta (Aβ) and phosphorylated tau protein (pTau) in the brain with underlying neuroinflammation. We aimed to develop a neuroprotective paradigm by loading verapamil (VRH) into hyaluronic acid-modified carbon quantum dots (CQDs) and comparing its effectiveness with the free form in an AD-like model in rats induced by lipopolysaccharide (LPS). The experimental rats were divided into seven groups: control, LPS, CQDs, early free VRH (FVRH), late FVRH, early verapamil carbon quantum dots (VCQDs), and late VCQDs. Characterizations of VCQDs, the behavioral performance of the rats, histopathological and immunohistochemical changes, some AD hallmarks, oxidative stress biomarkers, neuro-affecting genes, and DNA fragmentation were determined. VRH was successfully loaded into CQDs, which was confirmed by the measured parameters. VRH showed enhancement in cognitive functions, disruption to the architecture of the brain, decreased Aβ and pTau, increased antioxidant capacity, modifiable expression of genes, and a decline in DNA fragmentation. The loaded therapy was superior to the free drug. Moreover, the early intervention was better than the late, confirming the implication of the detected molecular targets in the development of AD. VRH showed multifaceted mechanisms in combating LPS-induced neurotoxicity through its anti-inflammatory and antioxidant properties, thereby mitigating the hallmarks of AD. Additionally, the synthesized nanosystem approach exhibited superior neuroprotection owing to the advantages offered by CQDs. However, finding new actionable biomarkers and molecular targets is of decisive importance to improve the outcomes for patients with AD. [ABSTRACT FROM AUTHOR]
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- 2024
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30. Modeling demyelination and endogenous remyelination in spinal cord ex vivo rat organotypic slice cultures.
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Hawker, Brooke, Dhakal, Muna, Connor, Bronwen, and McCaughey-Chapman, Amy
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MICROPHYSIOLOGICAL systems ,OLIGODENDROGLIA ,SPINAL cord ,DEMYELINATION ,NEUROLOGICAL disorders ,MYELIN sheath - Abstract
Introduction: Demyelination of the spinal cord is a prominent feature of multiple sclerosis (MS) and spinal cord injuries (SCI), where impaired neuronal communication between the brain and periphery has devastating consequences on neurological function. Demyelination precedes remyelination, an endogenous process in which oligodendrocyte precursor cells (OPCs) differentiate into mature, myelinating oligodendrocytes with the ability to restore the myelin sheath and reinstate functional nerve signaling. However, in MS or SCI, demyelination is more severe, persistent, and inhibitory to OPC-mediated remyelination, leading to a permanent loss of neuronal function. Currently, there are no effective treatments for demyelination, and existing pre-clinical models typically focus on brain tissue with little characterization of demyelination within the spinal cord. Organotypic slice cultures are a useful tool to study neurological disease, providing a more complex 3-dimensional system than standard 2-dimensional in vitro cell cultures. Methods: Building on our previously developed rat brain slice culture protocol, we have extended our findings to develop a rat longitudinal spinal cord ex vivo model of demyelination. Results: We generated rat longitudinal spinal cord slice cultures that remain viable for up to 6weeks in culture and retain key anatomical features of the spinal cord's cytoarchitecture. We show that treating longitudinal spinal cord slices with lysolecithin (LPC) induced robust demyelination with some endogenous remyelination, which was not seen following exposure to lipopolysaccharide (LPS). Discussion: Our ex vivo organotypic spinal cord slice culture system provides a platform to model demyelination and endogenous remyelination long-term, mimicking that observed in LPC-induced rodent models of demyelination. This platform is suitable for the development and testing of novel therapeutic strategies with ease of manipulation prior to in vivo experimentation. [ABSTRACT FROM AUTHOR]
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- 2024
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31. Genomic and biological insights of bacteriophages JNUWH1 and JNUWD in the arms race against bacterial resistance.
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Hengwei Zhang, Jiajia You, Xuewei Pan, Yanglu Hu, Zan Zhang, Xian Zhang, Weiguo Zhang, and Zhiming Rao
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BACTERIOPHAGES ,DRUG resistance in bacteria ,ARMS race ,BIOLOGICAL evolution ,ESCHERICHIA coli ,GENOMICS - Abstract
The coevolution of bacteria and bacteriophages has created a great diversity of mechanisms by which bacteria fight phage infection, and an equivalent diversity of mechanisms by which phages subvert bacterial immunity. Effective and continuous evolution by phages is necessary to deal with coevolving bacteria. In this study, to better understand the connection between phage genes and host range, we examine the isolation and genomic characterization of two bacteriophages, JNUWH1 and JNUWD, capable of infecting Escherichia coli. Sourced from factory fermentation pollutants, these phages were classified within the Siphoviridae family through TEM and comparative genomic analysis. Notably, the phages exhibited a viral burst size of 500 and 1,000 PFU/cell, with latent periods of 15 and 20 min, respectively. They displayed stability over a pH range of 5 to 10, with optimal activity at 37°C. The complete genomes of JNUWH1 and JNUWD were 44,785 bp and 43,818 bp, respectively. Phylogenetic analysis revealed their close genetic relationship to each other. Antibacterial assays demonstrated the phages' ability to inhibit E. coli growth for up to 24 h. Finally, through laboratory-driven adaptive evolution, we successfully identified strains for both JNUWH1 and JNUWD with mutations in receptors specifically targeting lipopolysaccharides (LPS) and the lptD gene. Overall, these phages hold promise as additives in fermentation products to counter E. coli, offering potential solutions in the context of evolving bacterial resistance. [ABSTRACT FROM AUTHOR]
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- 2024
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32. Regional Differences in Microbial Infiltration of Brain Tissue from Alzheimer's Disease Patients and Control Individuals.
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Jones, T. Bucky, Chu, Ping, Wilkey, Brooke, Lynch, Leigha, and Jentarra, Garilyn
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ALZHEIMER'S disease , *CEREBRAL amyloid angiopathy , *ALZHEIMER'S patients , *NEUROFIBRILLARY tangles , *LIPOTEICHOIC acid - Abstract
Alzheimer's disease (AD) is characterized by cognitive decline and neuropathology including amyloid beta (Aβ) plaques and neurofibrillary tangles (tau). Factors initiating or driving these pathologies remain unclear, though microbes have been increasingly implicated. Our data and others' findings indicate that microbes may be common constituents of the brain. It is notable that Aβ and tau have antimicrobial properties, suggesting a response to microbes in the brain. We used 16S rRNA sequencing to compare major bacterial phyla in post-mortem tissues from individuals exhibiting a range of neuropathology and cognitive status in two brain regions variably affected in AD. Our data indicate that strong regional differences exist, driven in part by the varied presence of Proteobacteria and Firmicutes. We confirmed our data using ELISA of bacterial lipopolysaccharide (LPS) and lipoteichoic acid in the same brain tissue. We identified a potential association between the composition of phyla and the presence of neuropathology but not cognitive status. Declining cognition and increasing pathology correlated closely with serum LPS, but not brain levels of LPS, although brain LPS showed a strong negative correlation with cerebral amyloid angiopathy. Collectively, our data suggest a region-specific heterogeneity of microbial populations in brain tissue potentially associated with neurodegenerative pathology. [ABSTRACT FROM AUTHOR]
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- 2024
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33. Regional modulation of toll‐like receptor signaling pathway genes in acute epididymitis in mice.
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Andrade, Alexandre D., Almeida, Priscila G. C., Mariani, Noemia A. P., Santos, Natalia C. M., Camargo, Isabela A., Martini, Poliana V., Kushima, Helio, Ai, Dingding, Avellar, Maria Christina W., Meinhardt, Andreas, Pleuger, Christiane, and Silva, Erick J. R.
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TOLL-like receptors , *CELLULAR signal transduction , *EPIDIDYMITIS , *TOLL-like receptor agonists , *VAS deferens - Abstract
Background: Region‐specific immune environments in the epididymis influence the immune responses to uropathogenic Escherichia coli (UPEC) infection, a relevant cause of epididymitis in men. Toll‐like receptors (TLRs) are essential to orchestrate immune responses against bacterial infections. The epididymis displays region‐specific inflammatory responses to bacterial‐derived TLR agonists, such as lipopolysaccharide (LPS; TLR4 agonist) and lipoteichoic acid (LTA; TLR2/TLR6 agonist), suggesting that TLR‐associated signaling pathways could influence the magnitude of inflammatory responses in epididymitis. Objectives: To investigate the expression and regulation of key genes associated with TLR4 and TLR2/TLR6 signaling pathways during epididymitis induced by UPEC, LPS, and LTA in mice. Material and methods: Epididymitis was induced in mice using UPEC, ultrapure LPS, or LTA, injected into the interstitial space of the initial segment or the lumen of the vas deferens close to the cauda epididymidis. Samples were harvested after 1, 5, and 10 days for UPEC‐treated animals and 6 and 24 h for LPS‐/LTA‐treated animals. Ex vivo epididymitis was induced by incubating epididymal regions from naive mice with LPS or LTA. RT‐qPCR and Western blot assays were conducted. Results: UPEC infection up‐regulated Tlr2, Tlr4, and Tlr6 transcripts and their associated signaling molecules Cd14, Ticam1, and Traf6 in the cauda epididymidis but not in the initial segment. In these epididymal regions, LPS and LTA differentially modulated Tlr2, Tlr4, Tlr6, Cd14, Myd88, Ticam1, Traf3, and Traf6 expression levels. NFKB and AP1 activation was required for LPS‐ and LTA‐induced up‐regulation of TLR‐associated signaling transcripts in the cauda epididymidis and initial segment, respectively. Conclusion: The dynamic modulation of TLR4 and TLR2/TLR6 signaling pathways gene expression during epididymitis indicates bacterial‐derived antigens elicit an increased tissue sensitivity to combat microbial infection in a spatial manner in the epididymis. Differential activation of TLR‐associated signaling pathways may contribute to fine‐tuning inflammatory responses along the epididymis. [ABSTRACT FROM AUTHOR]
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- 2024
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34. Antimicrobial peptide 2K4L inhibits the inflammatory response in macrophages and Caenorhabditis elegans and protects against LPS-induced septic shock in mice.
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Ji, Fangyu, Tian, Guoxu, and Shang, Dejing
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ANTIMICROBIAL peptides , *CAENORHABDITIS elegans , *SEPTIC shock , *AMINO acid residues , *INFLAMMATION , *MACROPHAGE inflammatory proteins - Abstract
2K4L is a rationally designed analog of the short α-helical peptide temporin-1CEc, a natural peptide isolated and purified from the skin secretions of the Chinese brown frog Rana chensinensis by substituting amino acid residues. 2K4L displayed improved and broad-spectrum antibacterial activity than temporin-1CEc in vitro. Here, the antibacterial and anti-inflammatory activities of 2K4L in macrophages, C. elegans and mice were investigated. The results demonstrated that 2K4L could enter THP-1 cells to kill a multidrug-resistant Acinetobacter baumannii strain (MRAB 0227) and a sensitive A. baumannii strain (AB 22933), as well as reduce proinflammatory responses induced by MRAB 0227 by inhibiting NF-κB signaling pathway. Similarly, 2K4L exhibited strong bactericidal activity against A. baumannii uptake into C. elegans, extending the lifespan and healthspan of the nematodes. Meanwhile, 2K4L alleviated the oxidative stress response by inhibiting the expression of core genes in the p38 MAPK/PMK-1 signaling pathway and downregulating the phosphorylation level of p38, thereby protecting the nematodes from damage by A. baumannii. Finally, in an LPS-induced septic model, 2K4L enhanced the survival of septic mice and decreased the production of proinflammatory cytokines by inhibiting the signaling protein expression of the MAPK and NF-κB signaling pathways and protecting LPS-induced septic mice from a lethal inflammatory response. In conclusion, 2K4L ameliorated LPS-induced inflammation both in vitro and in vivo. [ABSTRACT FROM AUTHOR]
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- 2024
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35. Is Methylglyoxal a Potential Biomarker for the Warburg Effect Induced by the Lipopolysaccharide Neuroinflammation Model?
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Vizuete, Adriana Fernanda Kuckartz and Gonçalves, Carlos-Alberto
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BIOMARKERS , *NEUROINFLAMMATION , *PYRUVALDEHYDE , *GLYCOLYSIS , *IMMUNE response , *LIPOPOLYSACCHARIDES , *LACTATES - Abstract
Methylglyoxal (MG) is considered a classical biomarker of diabetes mellitus and its comorbidities. However, a role for this compound in exacerbated immune responses, such as septicemia, is being increasingly observed and requires clarification, particularly in the context of neuroinflammatory responses. Herein, we used two different approaches (in vivo and acute hippocampal slice models) to investigate MG as a biomarker of neuroinflammation and the neuroimmunometabolic shift to glycolysis in lipopolysaccharide (LPS) inflammation models. Our data reinforce the hypothesis that LPS-induced neuroinflammation stimulates the cerebral innate immune response by increasing IL-1β, a classical pro-inflammatory cytokine, and the astrocyte reactive response, via elevating S100B secretion and GFAP levels. Acute neuroinflammation promotes an early neuroimmunometabolic shift to glycolysis by elevating glucose uptake, lactate release, PFK1, and PK activities. We observed high serum and cerebral MG levels, in association with a reduction in glyoxalase 1 detoxification activity, and a close correlation between serum and hippocampus MG levels with the systemic and neuroinflammatory responses to LPS. Findings strongly suggest a role for MG in immune responses. [ABSTRACT FROM AUTHOR]
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- 2024
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36. Anatomical location of injected microglia in different activation states and time course of injury determines survival of retinal ganglion cells after optic nerve crush.
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Siddiqui, Ahad M., Sabljic, Thomas F., and Ball, Alexander K.
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RETINAL ganglion cells , *OPTIC nerve , *MICROGLIA , *OPTIC nerve injuries , *CELL death , *VITREOUS body - Abstract
Background: Activated microglia release harmful substances to retinal ganglion cells (RGCs), but may also benefit by removing cellular debris and secreting neurotrophic factors. These paradoxical roles remain controversial because the nature and time-course of the injury that defines their role is unknown. The aim of this study was to determine if pharmacological manipulation of microglia to acquire a pro-inflammatory or pro-survival phenotype will exacerbate or enhance neuronal survival after injury.Material and methods: Treated HAP I (highly aggressively proliferating immortalized) microglia were injected into the vitreous or tail vein (T V) of female Sprague-Dawley rats. Retinas were examined at 4-14 days following optic nerve crush (ONC) and the number of surviving RGCs was determined.Results: Injection of untreated HAP I cells resulted in the greater loss of RGCs early after ONC when injected into the vitreous and later after ONC when injected into the T V. LP S activated HAP I cells injected into the vitreous resulted in greater RGC loss with and without injury. When injected into the T V with ONC there was no loss of RGCs 4 days after ONC but greater loss afterwards. Minocycline treated HAP I cells injected into the vitreous resulted in greater RGC survival than untreated HAP I cells. However, when injected into the T V with ONC there was greater loss of RGCs. These results suggest that optic nerve signals attract extrinsic microglia to the retina, resulting in a proinflammatory response.Conclusion: Neuroprotection or cytotoxicity of microglia depends on the type of activation, time course of the injury, and if they act on the axon or cell body. HAPI microglia migrate to the retina or optic nerve following optic nerve injury when injected into the vitreous or tail vein, respectively. Pretreatment with LPS or minocycline differentially effects retinal ganglion cell survival. In most cases, the result late in the injury process is greater retinal ganglion cell loss. We show here that neuroprotection is not solely determined by the microglial activation state but factors such as the environment and time-course of the injury. Culture microglia can be treated in vitro and then injected in vivo. The cells migrate to the site of injury, cell body of retinal ganglion cells if in the vitreous or to the optic nerve if injected in the tail vein. Retinal ganglion cell death is dependent on the location the microglia act, time-course of injury, and activation state. Proinflammatory microglia can be neuroprotective early in the injury when the primary site of action is on the axons whereas hypoactivated microglia are neuroprotective early in injury when they act on the soma. Later in the injury, both become detrimental. [ABSTRACT FROM AUTHOR]
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- 2024
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37. Conversion of notoginsenoside R1 to 3β,12β-dihydroxydammar-(E)-20(22),24-diene-6-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside by Lactiplantibacillus plantarum S165 enhanced protective effects of LPS-induced intestinal epithelial barrier injury in Caco-2 cells
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Wang, Penghui, Gao, Yansong, Yang, Ge, Zhao, Lei, Zhao, Zijian, and Li, Shengyu
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HIGH performance liquid chromatography , *LACTIC acid bacteria , *INTESTINAL injuries , *LIQUID chromatography , *FERMENTED foods , *SAPONINS - Abstract
Aims Microbial transformation to modify saponins and enhance their biological activities has received increasing attention in recent years. This study aimed to screen the strain that can biotransform notoginsenoside R1, identify the product and study its biological activity. Methods and results A lactic acid bacteria strain S165 with glycosidase-producing activity was isolated from traditional Chinese fermented foods, which was identified and grouped according to API 50 CHL kit and 16S rDNA sequence analysis. Subsequently, notoginsenoside R1 underwent a 30-day fermentation period by the strain S165, and the resulting products were analyzed using High-performance liquid chromatography (HPLC), Ultra-performance liquid chromatography (UPLC)-mass spectrometry (MS)/MS, and 13C-Nuclear magnetic resonance (NMR) techniques. Employing a model of Lipopolysaccharide (LPS)-induced damage to Caco-2 cells, the damage of Caco-2 cells was detected by Hoechst 33 258 staining, and the activity of notoginsenoside R1 biotransformation product was investigated by CCK-8 and western blotting assay. The strain S165 was identified as Lactiplantibacillus plantarum and was used to biotransform notoginsenoside R1. Through a 30-day biotransformation, L. plantarum S165 predominantly converts notoginsenoside R1 into 3β,12β-dihydroxydammar-(E)-20(22),24-diene-6-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside, temporarily named notoginsenoside T6 (NGT6) according to HPLC, UPLC-MS/MS, and 13C-NMR analysis. Results from CCK-8 and Hoechst 33258 staining indicated that the ability notoginsenoside T6 to alleviate the intestinal injury induced by LPS in the Caco-2 cell was stronger than that of notoginsenoside R1. In addition, Western blotting result showed that notoginsenoside T6 could prevent intestinal injury by protecting tight junction proteins (Claudin-1, Occludin, and ZO-1). Conclusion Notoginsenoside R1 was biotransformed into the notoginsenoside T6 by L. plantarum S165, and the biotransformed product showed an enhanced intestinal protective effect in vitro. [ABSTRACT FROM AUTHOR]
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- 2024
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38. Metabolic trade-offs in Neonatal sepsis triggered by TLR4 and TLR1/2 ligands result in unique dysfunctions in neural breathing circuits.
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Joana Alves, Michele, Browe, Brigitte M, Carolina Rodrigues Dias, Ana, Torres, Juliet M, Zaza, Giuliana, Bangudi, Suzy, Blackburn, Jessica, Wang, Wesley, de Araujo Fernandes- Junior, Silvio, Fadda, Paolo, Toland, Amanda, Baer, Lisa A., Stanford, Kristin I., Czeisler, Catherine, Garcia III, Alfredo J, and Javier Otero, José
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NEONATAL sepsis , *NEURAL circuitry , *LIGANDS (Biochemistry) , *ASTROCYTES , *GRAM-positive bacterial infections , *GRAM-negative bacterial diseases , *RAPHE nuclei - Abstract
• LPS and PAM3CSK4 which mimic gram-negative and gram-positive bacterial infection in neonates, respectively, leads to metabolic alterations and impairment in respiratory chemoreflexes. • LPS induces a robust neuroinflammation in brainstem tissue and brainstem enriched astrocytes, microglia, and neurons. • PAM3CSK4 induces to a smaller degree of inflammatory changes in brainstem without resulting in gene expression changes of enriched GLAST-1 positive astrocytes. • PAM3CSK4 leads to impaired anoxic chemoreflex and neurotransmission between preBötzinger complex and hypoglossal. • Machine learning analysis suggests IL6 as a potential mechanism for hypothermia-hypometabolic changes in neonatal sepsis through LPS. Neonatal sepsis remains one of the leading causes of mortality in newborns. Several brainstem-regulated physiological processes undergo disruption during neonatal sepsis. Mechanistic knowledge gaps exist at the interplay between metabolism and immune activation to brainstem neural circuits and pertinent physiological functions in neonates. To delineate this association, we induced systemic inflammation either by TLR4 (LPS) or TLR1/2 (PAM3CSK4) ligand administration in postnatal day 5 mice (PD5). Our findings show that LPS and PAM3CSK4 evoke substantial changes in respiration and metabolism. Physiological trade-offs led to hypometabolic-hypothermic responses due to LPS, but not PAM3CSK4, whereas to both TLR ligands blunted respiratory chemoreflexes. Neuroinflammatory pathways modulation in brainstem showed more robust effects in LPS than PAM3CSK4. Brainstem neurons, microglia, and astrocyte gene expression analyses showed unique responses to TLR ligands. PAM3CSK4 did not significantly modulate gene expression changes in GLAST-1 positive brainstem astrocytes. PD5 pups receiving PAM3CSK4 failed to maintain a prolonged metabolic state repression, which correlated to enhanced gasping latency and impaired autoresuscitation during anoxic chemoreflex challenges. In contrast, LPS administered pups showed no significant changes in anoxic chemoreflex. Electrophysiological studies from brainstem slices prepared from pups exposed to either TLR4 or PAM3CSK4 showed compromised transmission between preBötzinger complex and Hypoglossal as an exclusive response to the TLR1/2 ligand. Spatial gene expression analysis demonstrated a region-specific modulation of PAM3CSK4 within the raphe nucleus relative to other anatomical sites evaluated. Our findings suggest that metabolic changes due to inflammation might be a crucial tolerance mechanism for neonatal sepsis preserving neural control of breathing. [ABSTRACT FROM AUTHOR]
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- 2024
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39. Role of Bay of Bengal low‐pressure systems in the formation of mid‐tropospheric cyclones over the Arabian Sea and western India.
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Kushwaha, Pradeep, Sukhatme, Jai, and Nanjundiah, Ravi S
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METEOROLOGICAL research , *WEATHER forecasting , *WIND shear , *RAINFALL , *BUDGET - Abstract
Arabian Sea mid‐tropospheric cyclones (MTCs), responsible for extreme rainfall events in Western India, often coincide with monsoon low‐pressure systems (LPSs) over the Bay of Bengal. However, the influence of Bay of Bengal LPSs on the formation of Arabian Sea MTCs remains unclear. This study utilizes the Weather Research and Forecasting Model (WRF) to investigate the atmospheric connection between these two basins. By introducing a balanced bogus vortex over the Bay of Bengal, cyclonic systems are induced over the Arabian Sea in the majority of ensemble members, exhibiting characteristics consistent with observations. In particular, as the Bay of Bengal vortex moves westward, the middle tropospheric trough deepens, horizontal wind shear increases, the low‐level Arabian Sea stable inversion layer weakens, and the middle troposphere moisture content over Western India and the northeast Arabian Sea rises. Subsequently, MTC genesis occurs over the northeast Arabian Sea along the western edge of the trough within 2–4 days of model integration. A vorticity budget analysis highlights the critical role of vorticity advection and tilting during the initial 24 h of MTC genesis, while vortex stretching becomes the dominant vorticity source during rapid intensification. To substantiate these findings further, a mechanism denial experiment is conducted using a real‐world instance of a coexistent Arabian Sea MTC and Bay of Bengal LPS, replicated in the model. In this experiment, conditions unfavorable for LPS genesis are created by cooling and drying the Bay of Bengal. The results demonstrate that the absence or reduced intensity of the Bay of Bengal LPS inhibits formation of the Arabian Sea MTC. In all, this study presents compelling evidence for the significant influence of Bay of Bengal low‐pressure systems on the formation of severe weather‐inducing MTCs over the Arabian Sea and Western India. [ABSTRACT FROM AUTHOR]
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- 2024
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40. Differential effects of AKT1 and AKT2 on sleep–wake activity under basal conditions and in response to LPS challenge in mice.
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Cui, Meng, Meng, Pengfei, Wang, Shaohe, Feng, Qingyuan, Liu, Guangming, and Zhao, Peng
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WAKEFULNESS , *CONDITIONED response , *SLEEP duration , *SLEEP , *KNOCKOUT mice , *ALPHA rhythm - Abstract
Infectious challenge can trigger alterations in sleep–wake behavior. Accumulating evidence has shown that the serine/threonine kinases Akt1 and Akt2 are important targets in both physiological and infectious signaling processes. However, the involvement of Akt1 and Akt2 in sleep–wake activity under basal conditions and in response to inflammatory stimulation has not been established. In the present study, we assessed the precise role of Akt1 and Akt2 in sleep–wake behavior using electroencephalography (EEG)/electromyography (EMG) data from Akt1- and Akt2-deficient mice and wild-type (WT) mice. The results showed that both Akt1 and Akt2 deficiency affect sleep–wake activity, as indicated by reduced nonrapid eye movement (NREM) sleep and increased wakefulness in mutant mice compared to WT mice. Sleep amount and intensity (delta, theta and alpha activity) at night were also drastically attenuated in Akt1- and Akt2-deficient mice. Moreover, since Akt1 and Akt2 are involved in immune responses, we assessed their roles in the sleep response to the inflammatory stimulus lipopolysaccharide (LPS) throughout the following 24 h. We observed that the decrease in wakefulness and increase in NREM sleep induced by LPS were restored in Akt1 knockout mice but not in Akt2 knockout mice. Correspondingly, the decrease in the number of positive orexin-A neurons induced by LPS was abrogated in Akt1 knockout mice but not in Akt2 knockout mice. Our results revealed that both Akt1 and Akt2 deficiency affect the sleep response under basal conditions, but only Akt1 deficiency protects against the aberrant changes in sleep behavior induced by peripheral immune challenge. [ABSTRACT FROM AUTHOR]
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- 2024
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41. Intestinal Epithelial Co-Culture Sensitivity to Pro-Inflammatory Stimuli and Polyphenols Is Medium-Independent.
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Haddad, Michelle J., Zuluaga-Arango, Juanita, Mathieu, Hugo, Barbezier, Nicolas, and Anton, Pauline M.
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POLYPHENOLS , *INTESTINAL mucosa , *ESCHERICHIA coli , *INTESTINES , *CELL culture , *EPITHELIAL cells , *CATECHIN , *PLANT polyphenols - Abstract
The complexification of in vitro models requires the compatibility of cells with the same medium. Since immune cells are the most sensitive to growth conditions, growing intestinal epithelial cells in their usual medium seems to be necessary. This work was aimed at comparing the sensitivity of these epithelial cells to pro-inflammatory stimuli but also to dietary polyphenols in both DMEM and RPMI-1640 media. Co-cultures of Caco-2 and HT29-MTX cells were grown for 21 days in the two media before their stimulation with a cocktail of TNF-α (20 ng/mL), IL-1β (1 ng/mL), and IFN-γ (10 ng/mL) or with LPS (10 ng/mL) from E. coli (O111:B4). The role of catechins (15 µM), a dietary polyphenol, was evaluated after its incubation with the cells before their stimulation for 6 h. The RPMI-1640 medium did not alter the intensity of the inflammatory response observed with the cytokines. By contrast, LPS failed to stimulate the co-culture in inserts regardless of the medium used. Lastly, catechins were unable to prevent the pro-inflammatory response observed with the cytokines in the two media. The preservation of the response of this model of intestinal epithelium in RPMI-1640 medium is promising when considering its complexification to evaluate the complex cellular crosstalk leading to intestinal homeostasis. [ABSTRACT FROM AUTHOR]
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- 2024
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42. Multiple regulatory inputs including cell envelope stress orchestrate expression of the Escherichia coli rpoN operon.
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Sikora, Florian, Budja, Lara Veronika Perko, Milojevic, Olja, Ziemniewicz, Amelia, Dudys, Przemyslaw, and Görke, Boris
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GENE expression , *OPERONS , *CELL envelope (Biology) , *ESCHERICHIA coli , *CHEMICAL mutagenesis , *GENETIC transcription - Abstract
The rpoN operon, an important regulatory hub in Enterobacteriaceae, includes rpoN encoding sigma factor σ54, hpf involved in ribosome hibernation, rapZ regulating glucosamine‐6‐phosphate levels, and two genes encoding proteins of the nitrogen‐related phosphotransferase system. Little is known about regulatory mechanisms controlling the abundance of these proteins. This study employs transposon mutagenesis and chemical screens to dissect the complex expression of the rpoN operon. We find that envelope stress conditions trigger read‐through transcription into the rpoN operon from a promoter located upstream of the preceding lptA‐lptB locus. This promoter is controlled by the envelope stress sigma factor E and response regulator PhoP is required for its full response to a subset of stress signals. σE also stimulates ptsN‐rapZ‐npr expression using an element downstream of rpoN, presumably by interfering with mRNA processing by RNase E. Additionally, we identify a novel promoter in the 3′ end of rpoN that directs transcription of the distal genes in response to ethanol. Finally, we show that translation of hpf and ptsN is individually regulated by the RNA chaperone Hfq, perhaps involving small RNAs. Collectively, our work demonstrates that the rpoN operon is subject to complex regulation, integrating signals related to envelope stress and carbon source quality. [ABSTRACT FROM AUTHOR]
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- 2024
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43. The potential therapeutic effects of exosomes derived from bone marrow mesenchymal stem cells on ileum injury of a rat sepsis model (histological and immunohistochemical study).
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Elnegris, Heba M., Abdelrahman, Abeer A., and El-Roghy, Eman S.
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MESENCHYMAL stem cells , *LABORATORY rats , *TREATMENT effectiveness , *BIOLOGICAL evolution , *BONE marrow , *NEUROANATOMY - Abstract
Sepsis denotes a serious high mortality concern. The study was designed to evaluate the effect of mesenchymal stem cell exosomes (MSC-exosomes) on the evolution of the animal model of sepsis. In this study, 36 rats were distributed into three groups, (I) controls, (II) LPS-treated, and (III) LPS+MSC-EVs. Sepsis was simulated by administering E. coli-LPS to the laboratory animals. Group III was given MSC-exosomes four hours after the LPS injection. Forty-eight hours later rats were sacrificed. Ileum samples were excised, and processed for the histological assessment, immunohistochemical identification of CD44, and inducible nitric oxide synthase (iNOS). Ileum homogenate was used to estimate tumor necrosis factor α (TNF α) besides Cyclooxygenase-2 (COX 2). PCR was used for the detection of interleukin 1α (IL‑1α), and interleukin 17 (IL‑17). Statistical and morphometrical analysis was done. The LPS-treated group showed increased TNF-α, IL‑1α, IL‑17, and decreased COX 2. LPS administration led to cytoplasmic vacuolization of enterocytes, an increase in the vasculature, and cellular infiltrations invaded the lamina propria. There was a significant rise in goblet cells and the proportion of collagen fibers. Ultrastructurally, the enterocytes displayed nuclear irregularity, rough endoplasmic reticulum (rER) dilatation, and increased mitochondria number. Sepsis induces a significant increase in iNOS and a decrease in CD44 immune expressions. LPS+MSC-EVs group restored normal ileum structure and revealed a significant elevation in CD44 and a reduction in iNOS immunoreactions. LPS-sepsis induced an obvious ileum inflammatory deterioration ameliorated by MSC-exosomes, mostly through their antioxidant, anti-inflammatory, and anti-apoptotic properties. [ABSTRACT FROM AUTHOR]
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- 2024
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44. LECT2 Deletion Exacerbates Liver Steatosis and Macrophage Infiltration in a Male Mouse Model of LPS-mediated NASH.
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Tanida, Ryota, Goto, Hisanori, Takayama, Hiroaki, Nakano, Yujiro, Oo, Hein Ko, Galicia-Medina, Cynthia Monserrat, Takahashi, Kenta, Ishii, Kiyo-aki, Goli, Arman Syah, Matsuzaka, Takashi, Harada, Kenichi, and Takamura, Toshinari
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INTERLEUKIN-8 ,MALE models ,FATTY degeneration ,NON-alcoholic fatty liver disease ,LABORATORY mice - Abstract
Leukocyte cell-derived chemotaxin 2 (LECT2) is a protein initially isolated as a neutrophil chemotactic factor. We previously found that LECT2 is an obesity-associated hepatokine that senses liver fat and induces skeletal muscle insulin resistance. In addition, hepatocyte-derived LECT2 activates macrophage proinflammatory activity by reinforcing the lipopolysaccharide (LPS)-induced c-Jun N-terminal kinase signaling. Based on these findings, we examined the effect of LECT2 deletion on nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) caused by bacterial translocation. We created the bacterial translocation-mediated NAFLD/NASH model using LECT2 knockout mice (LECT2 KO) with 28 times a low-dose LPS injection under high-fat diet feeding conditions. LECT2 deletion exacerbated steatosis and significantly reduced p38 phosphorylation in the liver. In addition, LECT2 deletion increased macrophage infiltration with decreased M1/M2 ratios. LECT2 might contribute to protecting against lipid accumulation and macrophage activation in the liver under pathological conditions, which might be accomplished via p38 phosphorylation. This study provides novel aspects of LECT2 in the bacterial translocation-mediated NAFLD/NASH model. [ABSTRACT FROM AUTHOR]
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- 2024
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45. Low Dose Lipopolysaccharide-Induced Depressive-Like Phenotype is Mediated by Proinflammatory Cytokines in Mice and Role of Ketamine.
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Praharaj, Shuvranshu, Kalaichelvan, Vandurayanpet Kaliyamoorthy, Murugan, Vedigounder, Venkatachalam, Velappan, and Ahmad, Ishtiyaque
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LABORATORY mice ,ANHEDONIA ,MENTAL illness ,BODY weight ,TRANSLATIONAL research ,KETAMINE - Abstract
Background: Depression is a common mental illness, with an estimated 3.8% of global population affected. In the pathophysiology of depression, ketamine acts quickly in patients. Treatment with low-dose ketamine upon administration to stressed C57BL/6J mice is now a major translational research area to facilitate further innovation. Objectives: The present work was aimed to establish a depressant like animal model after 6 days of LPS injection, where LPS did not promote body weight loss. Materials and Methods: Peripheral administration of low dose of Lipopolysaccharide (LPS) activates cytokines and culminate in a distinct depressive-like behavioral syndrome, measured by increased duration of immobility in the forced swim and anhedonia in sucrose preference tests. Cytokines like TNF-α, IL-6, IL-1β and IFN-γ were determined in brain homogenate and in plasma using western blot performed with automated Jess system (ProteinSimple) and ELISA respectively. Results: Ketamine prevents development of depressive-like behavior by decreasing swimming behavior and increasing preference to sucrose in stressed animals. Ketamine treatment reduced the LPS induced secretion of IFN-γ (p<0.05 for 30 mpk), IL-6 (p<0.05 for 30 mpk), TNF-α (p<0.0001 for 30 mpk) and IL-1β in plasma. Similarly, ketamine treatment reduced the LPS induced secretion of IFN-γ (p<0.001 for 10 and 30 mpk), IL-6, TNF-α (p<0.01 for 10 and 30 mpk) and IL-1β (p<0.05 for 10 mpk, p<0.0001 for 30 mpk) in brain. The plasma and brain concentrations of ketamine were analysed using LC-MS/MS and Brain/ Plasma ratio (B/P) of ketamine at 10 and 30 mpk were calculated as 0.70 and 0.82 respectively. Conclusion: In summary, these data emphasizes that ketamine treatment modulate cytokine level, showed good brain to plasma exposure and provides its anti-stress effects in the C57BL/6 mouse strain, which may be possible reason for the anti-depression property and is relevant to human stress-induced depression. [ABSTRACT FROM AUTHOR]
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- 2024
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46. Hibifolin protected pro‐inflammatory response and oxidative stress in LPS‐induced acute lung injury through antioxidative enzymes and the AMPK2/Nrf‐2 pathway.
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Ni, Yung‐Lun, Shen, Huan‐Ting, Ng, Yan‐Yan, Chen, Shih‐Pin, Lee, Shiuan‐Shinn, Tseng, Ching‐Chi, Ho, Yung‐Chuan, and Kuan, Yu‐Hsiang
- Subjects
LUNG injuries ,OXIDATIVE stress ,HEMATOXYLIN & eosin staining ,PULMONARY edema ,ENZYMES ,LIPIDS - Abstract
ALI is a grave medical ailment that manifests as abrupt inflammation of the lungs and diminished oxygen levels. It poses a considerable challenge to the medical fraternity, with elevated rates of morbidity and mortality. Our research endeavors to investigate the potential of hibifolin, a flavonoid glucuronide, imbued with potent antioxidant properties, and its molecular mechanism to combat LPS‐induced ALI in mice. The study utilized ICR mice to create an ALI model induced by LPS. Prior to LPS administration, hibifolin was given at 10, 30, or 50 mg/kg, or dexamethasone was given at 1 mg/kg to assess its preventative impact. Changes in lung tissue, pulmonary edema, and lipid peroxidation were analyzed using H&E stain assay, lung wet/dry ratio assay, and MDA formation assay, respectively. Activity assay kits were used to measure MPO activity and antioxidative enzymes (SOD, CAT, GPx) activity in the lungs. Western blot assay was used to determine the phosphorylation of Nrf‐2 and AMPK2 in the lungs. Hibifolin demonstrated a concentration‐dependent improvement in LPS‐induced histopathologic pulmonary changes. This treatment notably mitigated pulmonary edema, lipid peroxidation, and MPO activity in ALI mice. Additionally, hibifolin successfully restored antioxidative enzyme activity in the lungs of ALI mice. Moreover, hibifolin effectively promoted Nrf‐2 phosphorylation and reinstated AMPK2 phosphorylation in the lungs of ALI mice. The results indicate that hibifolin could effectively alleviate the pathophysiological impact of LPS‐induced ALI. This is likely due to its antioxidative properties, which help to restore antioxidative enzyme activity and activate the AMPK2/Nrf2 pathway. These findings are valuable in terms of enhancing our knowledge of ALI treatment and pave the way for further investigation into hibifolin as a potential therapeutic option for lung injuries. [ABSTRACT FROM AUTHOR]
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- 2024
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47. LPS exacerbates TRPV4‐mediated itch through the intracellular TLR4‐PI3K signalling.
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Hao, Yanping, Wu, Liyan, Wang, Yuhui, Shan, Dongmei, Liu, Yifei, Feng, Jing, Chang, Yi, and Wang, Ting
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ITCHING ,TRPV cation channels ,SENSITIZATION (Neuropsychology) ,BACTERIAL diseases ,LIPOPOLYSACCHARIDES - Abstract
Pruritus is often accompanied with bacterial infections, but the underlying mechanism is not fully understood. Although previous studies revealed that lipopolysaccharides (LPS) could directly activate TRPV4 channel and TRPV4 is involved in the generation of both acute itch and chronic itch, whether and how LPS affects TRPV4‐mediated itch sensation remains unclear. Here, we showed that LPS‐mediated TRPV4 sensitization exacerbated GSK101‐induced scratching behaviour in mice. Moreover, this effect was compromised in TLR4‐knockout mice, suggesting LPS acted through a TLR4‐dependent mechanism. Mechanistically, LPS enhanced GSK101‐evoked calcium influx in mouse ear skin cells and HEK293T cells transfected with TRPV4. Further, LPS sensitized TRPV4 channel through the intracellular TLR4‐PI3K‐AKT signalling. In summary, our study found a modulatory role of LPS in TRPV4 function and highlighted the TLR4‐TRPV4 interaction in itch signal amplification. [ABSTRACT FROM AUTHOR]
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- 2024
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48. Reproducibility of LPS-Induced ex vivo Cytokine Response of Healthy Volunteers Using a Whole Blood Assay.
- Author
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Jorda, Anselm, Eberl, Sabine, Nussbaumer-Pröll, Alina, Sarhan, Maysa, Weber, Maria, Tegrovsky, Lara Elisabeth, Wahrmann, Markus, Jalali, Valentin al, Bergmann, Felix, Pracher, Lena, Leutzendorff, Amelie, Farlik, Matthias, Jilma, Bernd, and Zeitlinger, Markus
- Subjects
PEARSON correlation (Statistics) ,IMMUNE response ,ENDOTOXINS ,IMMUNOASSAY ,LIPOPOLYSACCHARIDES - Abstract
Introduction: Lipopolysaccharide (LPS) stimulation of human whole blood ex vivo has been widely used to investigate human innate immune responses. However, there are uncertainties regarding the reproducibility and reliability of this assay. Methods: In this prospective, single-center study, cytokine responses (interleukin 8, interferon-α, interferon-γ, interleukin 10, interleukin 1-β, interleukin 6, and tumor necrosis factor-α) to ex vivo whole blood LPS stimulation were assessed in 12 healthy volunteers. Cytokine levels were measured at 0, 2, and 4 h using a multiplex immunoassay (Luminex
® ). Stimulation was repeated after six weeks. We examined reproducibility across technical and biological replicates at baseline and between repeated experiments after 6 weeks based on the area under the curve (AUC) of the individual cytokines using Pearson's correlation coefficient and the mean coefficient of variation. Results: The lowest mean coefficients of variation were observed for the technical replicates (5.4 to 9.2%), followed by the biological replicates (8.1 to 24.8%), and the repeated experiments after 6 weeks (17 to 31.2%). Between the baseline and 6-week AUCs, the following Pearson correlation coefficients R were observed: interleukin 10, 0.97; interferon-α, 0.84; interleukin 1-β, 0.83; interleukin 8, 0.79; interleukin 6, 0.73; interferon-γ, 0.73; and tumor necrosis factor-α, 0.63. Discussion: The level of agreement between the baseline and week-6 cytokine response to ex vivo LPS stimulation was high across the seven cytokines analyzed. While interleukin 10 exhibited the lowest level of variability over time, tumor necrosis factor-α showed the highest variability in repeated experiments, which should be considered in the design and interpretation of future studies. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
49. Effect of Probiotic Bacteria on the Gut Microbiome of Mice with Lipopolysaccharide-Induced Inflammation.
- Author
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Gryaznova, Mariya, Burakova, Inna, Smirnova, Yuliya, Morozova, Polina, Chirkin, Egor, Gureev, Artem, Mikhaylov, Evgeny, Korneeva, Olga, and Syromyatnikov, Mikhail
- Subjects
LACTOBACILLUS plantarum ,GUT microbiome ,INTESTINAL mucosa ,PROBIOTICS ,NUCLEOTIDE sequencing ,LACTIC acid bacteria - Abstract
The role of lipopolysaccharide (LPS) in the development of diseases is clear, but the specific mechanisms remain poorly understood. This study aimed to investigate the microbiome aberrations in the guts of mice against the background of LPS, as well as the anti-inflammatory effect of probiotic supplementation with Lactobacillus plantarum from the gut, a mix of commercial probiotic lactic acid bacteria, and Weissella confusa isolated from milk using next-generation sequencing. LPS injections were found to induce inflammatory changes in the intestinal mucosa. These morphological changes were accompanied by a shift in the microbiota. We found no significant changes in the microbiome with probiotic supplementation compared to the LPS group. However, when Lactobacillus plantarum and a mix of commercial probiotic lactic acid bacteria were used, the intestinal mucosa was restored. Weissella confusa did not contribute to the morphological changes of the intestinal wall or the microbiome. Changes in the microbiome were observed with probiotic supplementation of Lactobacillus plantarum and a mix of commercial probiotic lactic acid bacteria compared to the control group. In addition, when Lactobacillus plantarum was used, we observed a decrease in the enrichment of the homocysteine and cysteine interconversion pathways with an increase in the L-histidine degradation pathway. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. The Cellular Microbiome of Visceral Organs: An Inherent Inhabitant of Parenchymal Cells.
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Sun, Xiaowei, Zhang, Hua, Zhang, Xiao, Gao, Wenmin, Zhou, Caiyun, Kou, Xuanxuan, Deng, Jingxin, and Zhang, Jiangang
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FLUORESCENCE in situ hybridization ,RNA ,CELL anatomy ,CELL nuclei ,GRAM-negative bacteria - Abstract
The cell is the basic unit of life. It is composed of organelles and various organic and inorganic biomolecules. Recent 16S ribosomal ribonucleic acid (16S rRNA) gene sequencing studies have revealed the presence of tissue bacteria in both tumor and normal tissues. Recently, we found that the liver microbiome resided in hepatocytes. Here, we further report on the cellular microbiome in the parenchymal cells of visceral organs as inherent inhabitants. We performed 16S rRNA gene sequencing on visceral organs of male adult Sprague Dawley (SD) rats, pregnant rats, newborn rats, and fetuses and placentas; then, we performed fluorescence in situ hybridization and immunofluorescence in visceral organs. Furthermore, we performed Western blotting on nuclear and cytoplasmic extractions of visceral organs of SD rats and cell lines HepG2, Huh-7, Hepa1-6, and HSC-T6. A high abundance of 16S rRNA gene was detected in the visceral organs of male adult, pregnant, newborn, and fetal rats as well as their placentas. The number of operational taxonomic units (OTUs) of visceral bacteria was higher than that of the feces and ileum bacteria. Bacterial 16S rRNA, lipopolysaccharide (LPS), and lipoteichoic acid (LTA) were found in the parenchymal cells of visceral organs, as well as in HepG2, Huh-7, HSC-T6, and Hepa1-6 cells. LPS consistently appeared in the nucleus of cells, while LTA was mainly found in the cytoplasm. In conclusion, the cellular microbiome is an intrinsic component of cells. Gram-negative bacteria are located in the nucleus, and Gram-positive bacteria are located in the cytoplasm. This differs from the gut microbiome and may be inherited. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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