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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]

Acute lung injury (ALI) is a life-threatening disorder stemmed mainly from an uncontrolled inflammatory response. Lipopolysaccharide (LPS) is commonly used to induce ALI animal models. Toll-like receptor 4 (TLR4) is the main receptor for LPS, and myeloid differentiation factor 88 (MyD88) is a key adaptor protein molecule in the Toll-like receptor (TLR) signaling pathway. Thus, MyD88 knockdown heterozygous mice (MyD88+/−) were used to investigate the effect of incomplete knockout of the MyD88 gene on indirect LPS-induced ALI through intraperitoneal injection of LPS. The LPS-induced ALI significantly upregulated MyD88 expression, and heterozygous mice with incomplete knockout of the MyD88 gene (MyD88+/−) ameliorated LPS-induced histopathological injury and collagen fiber deposition. Heterozygous mice with incomplete knockout of the MyD88 gene (MyD88+/−) inhibited LPS-induced nuclear factor-κB (NF-κB) pathway activation, but TLR-4 expression tended to be upregulated. Incomplete knockdown of the MyD88 gene also downregulated LPS-induced expression of IL1-β, IL-6, TNF-α, TGF-β, SMAD2, and α-SMA. The transcriptome sequencing also revealed significant changes in LPS-regulated genes (such as IL-17 signaling pathway genes) after the incomplete knockdown of MyD88. In conclusion, this paper clarified that LPS activates the downstream NF-κB pathway depending on the MyD88 signaling pathway, which induces the secretion of inflammatory cytokines such as IL-1β/IL-6/TNF-α and ultimately triggers ALI. Incomplete knockdown of the MyD88 reverses LPS-induced lung fibrosis, which confirmed the vital role of MyD88 in LPS-induced ALI. [ABSTRACT FROM AUTHOR]

Circadian disruption is involved in the progress of sepsis-induced cardiomyopathy (SICM), one of the leading causes of death in sepsis. The molecular mechanism remains ambiguous. In this study, LPS was used to build SICM model in H9c2 cell. The results suggested that LPS induced cytotoxicity via increasing ferroptosis over the time of course. After screening the expressions of six circadian genes, the circadian swing of Bmal1 was dramatically restrained by LPS in H9c2 cell of SIMC vitro model. PcDNA and siRNA were used to upregulate and downregulate Bmal1 and confirmed that Bmal1 inhibited LPS-triggered ferroptosis in H9c2 cells. Then, the results suggested that AKT/p53 pathway was restrained by LPS in H9c2 cell. Rescue test indicated that Bmal1 inhibited LPS-triggered ferroptosis via AKT/p53 pathway in H9c2 cells. In summary, our findings demonstrated that LPS induced cytotoxicity via increasing ferroptosis over the time of course in H9c2 cells and Bmal1 inhibited this toxicity of LPS via AKT/p53 pathway. Although further studies are needed, our findings may contribute to a new insight to mechanism of SICM. [ABSTRACT FROM AUTHOR]

Inflammation in muscle induces the synthesis of mediators that can impair protein synthesis and enhance proteolysis, and when sustained lead to muscle atrophy. Furthermore, muscle-derived mediators that are secreted may participate in disrupting the function of other peripheral organs. Selective identification of newly synthesized proteins can provide insight on biological processes that depend on the continued synthesis of specific proteins to maintain homeostasis as well as those proteins that are up- or down-regulated in response to inflammation. We used puromycin-associated nascent chain proteomics (PUNCH-P) to characterize new protein synthesis in C2C12 myotubes and changes resulting from their exposure to the inflammatory mediators lipopolysaccharide (LPS) and interferon (IFN)-γ for either a short (4 h) or prolonged (16 h) time period. We identified sequences of nascent polypeptide chains belonging to a total of 1523 proteins and report their detection from three independent samples of each condition at each time point. The identified nascent proteins correspond to approximately 15% of presently known proteins in C2C12 myotubes and are enriched in specific cellular components and pathways. A subset of these proteins was identified only in treated samples and has functional characteristics consistent with the synthesis of specific new proteins in response to LPS/IFNγ. Thus, the identification of proteins from their nascent polypeptide chains provides a resource to analyze the role of new synthesis of proteins in both protein homeostasis and in proteome responses to stimuli in C2C12 myotubes. Our results reveal a profile of actively translating proteins for specific cellular components and biological processes in normal C2C12 myotubes and a different enrichment of proteins in response to LPS/IFNγ. Collectively, our data disclose a highly interconnected network that integrates the regulation of cellular proteostasis and reveal a diverse immune response to inflammation in muscle which may underlie the concomitantly observed atrophy and be important in inter-organ communication. [ABSTRACT FROM AUTHOR]

Emodin, the effective component of the traditional Chinese medicine Dahuang, has anti-inflammatory effects. However, the protective effects and potential mechanisms of emodin are not clear. This study investigated the protective effects and potential mechanisms of emodin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in vitro and in vivo. In vivo, we designed an LPS-induced ALI rat model. In vitro, we chose the J774A.1 cell line to establish an inflammatory cellular model, and knocked down NOD-like receptor family pyrin domain containing 3 (NLRP3) using small interfering RNA. The mRNA and protein expression of NLRP3, a C-terminal caspase recruitment domain (ASC), caspase 1 (CASP1), and gasdermin D (GSDMD) in cells and lung tissues were detected by western blot and real-time quantitative polymerase chain reaction (PCR). The expression levels of interleukin 1 beta (IL-1β) and IL-18 in the serum and supernatant were determined by the enzyme-linked immunosorbent assay. The degree of pathological injury in lung tissue was evaluated by hematoxylin and eosin (H&E) staining. In vitro, we demonstrated that emodin could inhibit NLRP3 and then inhibit the expression of ASC, CASP1, GSDMD, IL-1β, and IL-18. In vivo, we confirmed that emodin had protective effects on LPS-induced ALI and inhibitory effects on NLRP3 inflammasome -dependent pyroptosis. Emodin showed excellent protective effects against LPS-induced ALI by regulating the NLRP3 inflammasome-dependent pyroptosis signaling pathway. [ABSTRACT FROM AUTHOR]

A new method for targeting lung infections is of great interest using biodegradable nanoparticles. In this study, bergenin-loaded BSA NPs were developed against lung injury. Briefly, bergenin-loaded bovine serum albumin nanoparticles (BG@BSA NPs) were synthesized and characterized. HPLC recorded the major peak of bergenin. UV–Vis spectra had an absorbance at 376 nm. XRD revealed the presence of crystalline particles. FTIR confirmed the occurrence of functionalized molecules in the synthesized NPs. The particles were highly stable with a net negative charge of − 24.2. The morphology of NPs was determined by SEM and TEM. The mean particle size was 124.26 nm. The production of NO by NR8383 cells was decreased by BG@BSA NPs. Also, in mice, lipopolysaccharide-mediated acute lung inflammation was induced. BG@BSA NPs reduced macrophages and neutrophils in BALF and remarkably enhanced wet weight-to-dry weight (W/D) ratios and myeloperoxidase (MPO) activity. Further, BG@BSA NPs inhibited the production of inflammatory cells as well as tumor necrosis factor. The histopathological studies revealed that the damage and neutrophil infiltration were greatly inhibited by BG@BSA NPs. This indicates that BG@BSA NPs may be used to treat lung infections. Therefore, this study has given new insight into producing an active drug for the treatment of lung-associated diseases in the future. [ABSTRACT FROM AUTHOR]

Supervillin (SVIL) is an actin-binding and membrane-associated protein, which belongs to villin/gelsolin family. It has been reported that SVIL was involved in the regulation of macrophages' movement and lipopolysaccharide (LPS) increased the SVIL mRNA expression in neutrophils, but the underlying mechanisms remain unknown. This work investigated the underlying molecular mechanisms of LPS regulating SVIL expression in macrophages and hence the possible role of SVIL in LPS-induced inflammation. We found that in THP-1-derived macrophages, LPS obviously increased SVIL mRNA and protein expression. Inhibition of TLR4 by Resatorvid (Res) remarkably reversed the LPS-induced SVIL expression. Additionally, inhibition of ERK1/2 signaling pathway (by U0126 or GDC-0994) and NF-κB (by BAY) significantly reduced the LPS-induced SVIL expression. Interestingly, down-regulation of SVIL by SVIL-specific shRNAs significantly attenuated the expression of IL-6, IL-1β & TNF-α induced by LPS at both mRNA and protein levels. Furthermore, we also observed that SVIL knockdown decreased the proportion of cells in G2/M phase and increased the proportion of cells in S & G0-1 phase of THP-1 derived macrophages, but did not influence the cell viability. Taken together, we demonstrated that LPS induced the expression of SVIL via activating TLR4/NF-κB and ERK1/2 MAPK pathways, and SVIL participated in the inflammatory response of LPS-induced IL-6, IL-1β and TNF-α upregulation in macrophages. [ABSTRACT FROM AUTHOR]

Dihydrotanshinone (DIH) is an extract of Salvia miltiorrhiza Bunge. It has been reported that DIH could regulate NF-κB signaling pathway. The aim of this study was to investigate whether DIH could protect mice from lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. In this study, sixty mice were randomly divided into five groups, one group as blank control group, the second group as LPS control group, and the last three groups were pre-injected with different doses of DIH and then inhaled LPS for experimental comparison. After 12 h of LPS treatment, the wet-dry ratio, histopathlogical changes, and myeloperoxidase (MPO) activity of lungs were measured. In addition, ELISA kits were used to measure the levels of TNF-α and IL-1β inflammatory cytokines in bronchoalveolar lavage fluids (BALF), and western blot analysis was used to measure the activity of NF-κB signaling pathway. The results demonstrated that DIH could effectively reduce pulmonary edema, MPO activity, and improve the lung histopathlogical changes. Furthermore, DIH suppressed the levels of inflammatory cytokines in BALF, such as TNF-α and IL-1β. In addition, DIH could also downregulate the activity of NF-κB signaling pathway. We also found that DIH dose-dependently increased the expression of LXRα. In addition, DIH could inhibit LPS-induced IL-8 production and NF-κB activation in A549 cells. And the inhibitory effects were reversed by LXRα inhibitor geranylgeranyl pyrophosphate (GGPP). Therefore, we speculate that DIH regulates LPS-induced ALI in mice by increasing LXRα expression, which subsequently inhibiting NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is a type of serious clinical syndrome leading to morbidity and mortality. However, the precise pathogenesis of ALI remains elusive. Here, we implemented an integrative meta-analysis of six GEO microarray studies with 76 samples in the ALI mouse model. A total of 958 differentially expressed genes (DEGs) were identified in LPS relative to normal samples. Then, a network-based meta-analysis was used to mine core DEGs and to unfold the interactions among these genes. We found that Ebi3 was the top upregulated genes in the LPS-induced ALI. GO, KEGG, and GSEA analyses were performed for functional annotation. qRT-PCR revealed augmented expression of six candidate genes (Stat1, Syk, Jak3, Rac2, Ripk1, and Traf6) in the established ALI mouse model with LPS exposure. Taken together, our study investigated comprehensively hub DEGs and their networks for LPS-stimulated ALI, which might afford an additional approach to determine biomarkers and therapeutic targets and explore the molecular pathophysiology toward ALI. [ABSTRACT FROM AUTHOR]

Sweroside, as one of the main components of Swertia L. in Gentianaceae, has the effect of clearing heat and detoxifying. In previous studies, sweroside has been reported to have anti-inflammatory effect on LPS-induced inflammation by alleviating NF-κB signaling pathway. In this paper, we investigate the anti-inflammatory effects of sweroside by establishing LPS-induced acute lung injury (ALI) model in mice. Experimental results showed that sweroside could reduce the wet-to-dry ratio of the lung and inhibit MPO activity. In addition, it turned out that sweroside reduced pathological changes in lung tissue and the numbers of inflammatory cells. Moreover, sweroside significantly reduced the levels of inflammatory cytokines and down-regulated the NF-κB signaling pathway. And the results demonstrated that sweroside could increase the expression of SIRT1, and the protective effects of sweroside on LPS-induced ALI were reversed by SIRT1 inhibitor EX-527. In conclusion, sweroside can protect LPS-induced ALI mice through inhibiting inflammation. [ABSTRACT FROM AUTHOR]

Sepsis-induced lung injury was the most common cause of death in patients. This study aimed to investigate whether PD-L1 regulates the inflammation in LPS-induced lung epithelial cells and vascular endothelial cells by interacting with the HIF-1α signaling pathway. Sepsis-induced lung injury mice were constructed by cecal ligation and puncture (CLP) procedure, and lipopolysaccharide (LPS)-induced lung epithelial cells and vascular endothelial cells simulate the sepsis-induced lung injury model in vitro. Hematoxylin-eosin (HE) staining detected the morphological changes of the lung tissues, and immunohistochemistry (IHC) detected the PD-L1 expression in lung tissues. Bicinchoninic acid (BCA) assay determined the protein concentration in bronchial alveolar lavage fluid (BALF). The number of PD-1 (+) cells in blood was detected by flow cytometry. The apoptosis in lung tissues and LPS-induced cells was analyzed by TUNEL assay. The inflammatory factor levels and HIF-1α in lung tissues and LPS-induced cells were analyzed by ELISA. The transfection effects of KD-PDL1 or KD-HIF1A in lung epithelial cells and vascular endothelial cells were confirmed by qRT-PCR analysis. The protein expression related to the PD-L1- and HIF-1α-related pathway was determined by Western blot analysis. As a result, LMT-28, as an IL-6 inhibitor, alleviated lung injury and suppressed the apoptosis and inflammation in lung tissues in BALF and the number of PD-1 (+) cells in blood. Sepsis-induced lung injury activated the PD-L1- and HIF-1α-related pathway, while LMT-28 could not completely inhibit the pathway. In addition, downregulation of PD-L1 or downregulation of HIF-1α suppressed the apoptosis and alleviated the inflammation in LPS-induced lung epithelial cells and vascular endothelial cells. Downregulation of PD-L1 had significant effects on lung epithelial cells but had greater effects on vascular endothelial cells. Downregulation of HIF-1α could decrease PD-L1 expression, and downregulation of PD-L1 could also suppress the protein expression of HIF-1α and related pathways. In conclusion, downregulation of PD-L1 alleviated the inflammation in LPS-induced lung epithelial cells and vascular endothelial cells by suppressing the HIF-1α signaling pathway. [ABSTRACT FROM AUTHOR]

The blood-brain barrier (BBB) is important for protecting the brain tissue by selectively exchanging substances between the blood and brain. The integrity of the BBB can be damaged by multiple factors, including oxidative stress and inflammation. Ramelteon is an oral hypnotic drug, and in the present study, we investigated its protective effect on BBB damage, as well as the underlying mechanism. LPS was used to induce BBB damage on mice and stimulate injury on endothelial cells. Evans blue staining assay was used to measure the brain permeability. The expressions of ZO-1 and Occludin were evaluated using immunostaining and Western blot in the brain tissue and endothelial cells, respectively. qRT-PCR and ELISA were used to detect the production of IL-1β and MCP-1 in the brain vessels. TBA assay was utilized to examine the concentration of MDA in the brain tissue and endothelial cells. The expression of Nrf2 in the nucleus and NQO1 were determined using Western blot assay. The endothelial permeability of the monolayer was examined using the FITC-dextran permeation assay. Firstly, the increased brain permeability and downregulated expression of tight junction proteins in the brain tissue induced by LPS were significantly reversed by treatment with Ramelteon, accompanied by the decrease in the production of IL-1β and MCP-1 in the vessels in mice. Also, the Nrf2 signaling was activated and oxidative stress in the brain vessels was alleviated by treatment with Ramelteon. Secondly, LPS-induced increase in endothelial monolayer permeability and decrease in tight junction protein expression in bEnd.3 brain endothelial cells were significantly reversed by Ramelteon, accompanied by activated Nrf2 signaling and alleviated oxidative stress. Lastly, the protective effects of Ramelteon against LPS-induced reduction of ZO-1 and Occludin, and the increase in endothelial monolayer permeability were dramatically abolished by silencing Nrf2. Ramelteon might ameliorate LPS-induced hyperpermeability of the BBB by activating the Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

Periodontitis is a common chronic inflammation that often occurs in adults. Circular RNAs (circRNAs) play a vital role in inflammation-related diseases. However, the role and potential basis of hsa_circ_0085289 in periodontitis remain unknown. Periodontal ligament cells (PDLCs) were exposed to lipopolysaccharide (LPS) to mimic periodontitis. The levels of circ_0085289, let-7f-5p, and suppressor of cytokine signaling 6 (SOCS6) were determined using qRT-PCR and western blot. The release of inflammatory cytokines was measured via enzyme-linked immunosorbent assay (ELISA). Cell viability and apoptosis were determined using Cell Counting Kit-8, flow cytometry, Caspase-3 Assay Kit, and western blot assays. The association between let-7f-5p and circ_0085289/SOCS6 was validated via dual-luciferase reporter, RNA pull-down, and RIP assays. Circ_0085289 and SOCS6 levels were reduced, and let-7f-5p level was increased in periodontitis patients and LPS-treated PDLCs. LPS stimulation caused PDLC injury and circ_0085289 downregulation. Moreover, circ_0085289 upregulation or let-7f-5p downregulation diminished LPS-triggered PDLC injury. Besides, circ_0085289 promoted SOCS6 expression by absorbing let-7f-5p. Circ_0085289 alleviated LPS-stimulated PDLC injury via targeting let-7f-5p. Moreover, let-7f-5p targeted SOCS6 to affect LPS-resulted PDLC injury. Circ_0085289 alleviated PDLC injury induced by LPS stimulation via modulating let-7f-5p/SOCS6 axis, suggesting a promising biomarker for periodontitis treatment. [ABSTRACT FROM AUTHOR]

Endometritis is a common inflammatory disease in uterine tissues that leads to animal infertility. Among the causes, Escherichia coli infection is one of the main reasons. Interferon-tau (IFN-τ) is the initial pregnancy signal for ruminant embryos and can induce immune tolerance in humans and other species. However, there are scarce reports on whether IFN-τ has a regulatory effect on endometrial inflammatory damage through HMGB1-NF-κB signalling. The purpose of this study was to investigate the regulatory mechanism of IFN-τ in HMGB1-NF-κB signalling in LPS-induced endometritis. ELISA and qPCR were used to detect the expression of LPS-induced pro-inflammatory cytokines in bovine endometrial epithelial cells (bEECs or BEND) under IFN-τ intervention, and the levels of HMGB1, p-IKK and p-p65 were detected by Western blotting. The nuclear translocation of NF-κB p65 was determined through immunofluorescence. In addition, bEECs were transfected with si-HMGB1 to elucidate the key role of HMGB1 and IFN-τ in the endometrial inflammatory cascade. The results indicated that IFN-τ inhibits the expression of related pro-inflammatory cytokines in an inflammatory injury model of bovine endometrial epithelial cells induced by LPS. Furthermore, experiments have proven that IFN-τ has protective effects on E. coli endotoxin-induced endometritis in mice in vivo. IFN-τ inhibited the HMGB1-NF-κB axis and significantly reduced the secretion of pro-inflammatory cytokines, the expression of HMGB1 protein and the levels of IKK and NF-κB p65 phosphorylation. In summary, our results showed that IFN-τ resists E. coli endotoxin-induced endometritis by attenuating HMGB1/NF-κB signalling. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is an urgent disease lacking effective therapies, resulting in relatively high morbidity and mortality. The pathological mechanism of ALI is reported to be related to excessive inflammation and activated oxidative stress. The present study aims to investigate the protective effects of the DPP-4 inhibitor Trelagliptin against lipopolysaccharide (LPS)-induced ALI and the underlying mechanism. LPS was used to induce ALI mice models. The pathological condition of ALI mice was evaluated using MPO activity assay, lung wet to dry weight ratio detection, and HE staining on the lung tissues. Lung function was assessed using a spirometer. The oxidative stress level in the lung tissues was checked by MDA measurement and GPx detection using commercial kits. The leukocyte and neutrophil numbers were determined using a hemocytometer and the total concentration of protein in the BALF was detected using a bicinchoninic acid method. The expression levels of TNF-α, IL-6, and CXCL2 in the lung tissues were evaluated using qRT-PCR and ELISA. Western blot analysis was used to determine the expression levels of TLR4 and p-NF-κB p65. LPS-induced elevated MPO activity, pulmonary wet to dry weight ratio, airway resistance (RAW), the total number of leukocytes and neutrophils, production of inflammatory factors, decreased pulmonary dynamic compliance (Cdyn), and peak expiratory flow (PEF), and an aggravated histopathological state (such as disordered alveolar structure, significant pulmonary interstitial edema, and large numbers of red blood cells and inflammatory cells in the alveolar cavity) were significantly reversed by the administration of Trelagliptin. The TLR4/NF-κB signaling pathway was activated and oxidative stress was induced by stimulation with LPS; however, both effects were suppressed by the administration of Trelagliptin. Trelagliptin might alleviate LPS-induced inflammation and oxidative stress in acute lung injury mice. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune and inflammatory disease with strong genetic influence, especially upon immune response components. Several cytokines from the toll-like receptors activation pathway display recognized role for RA establishment. However, few studies have verified the role of key mediators such as MYD88 gene and its genetic variants. In the present study, we aim to evaluate the rs6853 functional single-nucleotide variation (SNV) role in RA etiopathogenesis, clinical severity status, and its impact in MYD88 mRNA levels and IL-lβ protein levels. For the association study, a total of 423 RA patients and 346 health individuals, enrolled as control, from Northeast and Southeast Brazil were genotyped using specific Taqman probe. For the gene expression assays, we performed a MYD88 rs6853 genotype-guided monocyte cell culture divided into non-stimulated and lypopolysaccharides (LPS)-stimulated cells from healthy individuals. MYD88 gene expression was measured using primer specifics while IL-1β levels were evaluated by ELISA. We observed that A allele and AA genotype were associated to an increased risk to RA development (OR = 1.60; 95% CI 1.24–2.08; p = 0.0004/OR = 2.83; 95% CI 1.25–6.41; p = 0.0152). The AA genotype exhibited lower MYD88 mRNA levels than GG genotype in non-stimulated monocyte cell culture (FC − 3.83; p = 0.003). Additionally, we verified an increase of IL-1β levels when AA genotype non-stimulated monocytes were compared to AA genotype LPS-stimulates (p = 0.021). In summary, MYD88 rs6853 polymorphism associated to RA development in our Brazilian cohort and showed influence upon MYD88 mRNA levels' expression and IL-lβ production. [ABSTRACT FROM AUTHOR]

Sepsis is a disease that is characterized by a severe systemic inflammatory response to microbial infection and lipopolysaccharide (LPS) and is a well-known inducer of sepsis, as well as endothelial cell hyperpermeability. In the present study, we confirm the elevation of CXC chemokine ligand 13 (CXCL13) in sepsis patients. We also show that LPS exposure increases the release of CXCL13, as well as the mRNA and protein expression of CXCL13 and its receptor, CXC chemokine receptor 5 (CXCR5) in human umbilical vein endothelial cells (HUVECs) in a dose- and time-dependent manner. We also examined the effects of CXCL13 knockdown on LPS-mediated endothelial hyperpermeability and tight junction (TJ) protein expression in HUVECs. Our results show that HUVECs exposed to LPS result in a significant decrease in transendothelial electrical resistance (TER) and TJ protein (Zonula occluden-1, occludin, and claudin-4) expression, and a notable increase in fluorescein isothiocyanate (FITC)-dextran flux and p38 phosphorylation, which was partially reversed by CXCL13 knockdown. Recombinant CXCL13 treatment had a similar effect as LPS exposure, which was attenuated by a p38 inhibitor, SB203580. Moreover, the CXCL13-neutralizing antibody significantly increased the survival rate of LPS-induced sepsis mice. Collectively, our results show that CXCL13 plays a key role in LPS-induced endothelium hyperpermeability via regulating p38 signaling and suggests that therapeutically targeting CXCL13 may be beneficial for the treatment of sepsis. [ABSTRACT FROM AUTHOR]

Periodontitis is a dental plaque–induced chronic inflammatory disease. Long-term exposure of the host to periodontal pathogens leads to a hyporesponsive state to the following stimulations, which is described as endotoxin tolerance. Neutrophils are the most abundant innate immune cells in the body. To clarify the roles of endotoxin tolerance in periodontitis, inflammatory responses in Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS)–tolerized neutrophils were explored in this study. Here, apoptosis and respiratory burst in neutrophils upon single or repeated P. gingivalis LPS stimulations were explored by flow cytometry. Cytokine production (TNF-α, IL-8, and IL-10) in tolerized neutrophils or neutrophils co-cultured with peripheral blood mononuclear cells was determined by ELISA. Phagocytosis of P. gingivalis by tolerized neutrophils was also assayed by flow cytometry. In addition, quality and quantitation of neutrophil extracellular trap (NET) formation were detected using immunofluorescence microscope and microplate reader, respectively. The protein expressions of extracellular signal–regulated kinase1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (p38 MAPK) were examined to identify possible mechanisms for the abovementioned changes. Tolerance induced by P. gingivalis LPS significantly suppressed apoptosis, reactive oxygen species (ROS) generation, and phagocytosis in neutrophils (p < 0.05). In both neutrophils alone and co-culture system, repeated P. gingivalis LPS stimulations significantly decreased TNF-α production, but increased IL-10 secretion (p < 0.05). Moreover, in tolerized neutrophils, NET formations were strengthened and there were more released extracellular DNA (p < 0.05). In P. gingivalis LPS-tolerized neutrophils, phosphorylation of ERK1/2 was suppressed compared with that in non-tolerized cells. Taken together, immune responses in neutrophils were reprogrammed by P. gingivalis LPS-induced tolerance, which might be related with the development of inflammation in periodontal tissues. Moreover, ERK1/2 might play important roles in endotoxin tolerance triggered by P. gingivalis LPS. [ABSTRACT FROM AUTHOR]

Chronic inflammatory diseases affect bone and teeth health tremendously. Characterized by osteolytic lesion and hyperactive osteoclastogenesis, inflammatory bone diseases are short of effective therapeutics and therefore highlight the importance of understanding pathogenesis and developing ideal medications. Reactive oxygen species (ROS) play a prominent role in the innate immune response of activated macrophages, as well as in the physiological signaling of osteoclasts (OCs) differentiation. N-acetylcysteine (NAC) is a potent ROS scavenger and a potential option for treating diseases characterized by excessive ROS generation. However, whether NAC can protect physiological bone remodeling from in vivo inflammatory conditions is largely undefined. We applied NAC treatment on lipopolysaccharide (LPS)-induced inflammatory osteolysis mice model and found that NAC could attenuate bone erosion and protect mice against LPS-induced osteolysis, due to the suppressive effect on osteoclastogenesis and stimulated effect on osteogenesis. Moreover, in vitro study demonstrated that, in OC precursors (pre-OCs), LPS-stimulated expressions of OC marker genes, such as tartrate-resistant acid phosphatase type 5 (Acp5), cathepsin K (Ctsk), OC stimulatory transmembrane protein (Oc-stamp), dendritic cell–specific transmembrane protein (Dc-stamp), and nuclear factor of activated T cells 1 (NFATc1), were all reduced because of the NAC pretreatment, thereby adversely affecting OC function including F-actin ring formation and bone resorption. Further mechanism study showed that NAC blocked LPS-induced ROS formation in both macrophages and pre-OCs, cutting off the LPS-stimulated autocrine/paracrine mechanism during inflammatory osteolysis. Our findings reveal that NAC attenuates inflammatory osteolysis via the elimination of ROS formation during LPS-stimulated osteoclastogenesis, and provide a potential therapeutic approach to treat inflammatory bone disease. [ABSTRACT FROM AUTHOR]

The Nod-like receptor protein 3 (NLRP3) inflammasome is a multi-protein complex composed of NLRP3, pro-caspase-1, and apoptosis-associated speck-like protein that contains a caspase recruitment domain (ASC). After NLRP3 priming by lipopolysaccharide (LPS), the ligand of toll-like receptor 4 (TLR4), activation of the NLRP3 inflammasome triggers caspase-1 maturation, leading to pyroptosis and release of interleukin-1beta (IL-1beta). Expression of TLR4 modulates LPS-triggered inflammatory cascades as well as the NLRP3 signaling. L-type calcium channel antagonists are widely used as anti-hypertensive drugs and also exert anti-inflammatory effects through inhibiting release of cytokines including IL-1beta. However, few studies reveal effects of L-type calcium channel antagonists on the NLRP3 inflammasome. In this study, we investigated the effects of nicardipine and verapamil, both L-type calcium channel antagonists, on the NLRP3 inflammasome using differentiated THP-1 cells. Pyroptosis or levels of IL-1beta and caspase-1 were assayed by flow cytometry or enzyme-linked immunosorbent assay, respectively. ASC oligomerization was assayed by immunofluorescence microscopy. Expression of NLRP3 or TLR4 was assayed by polymerase chain reaction and immunoblotting. Nuclear factor-kappaB (NF-kappaB) pathway was also studied. Our results showed that pyroptosis and IL-1beta release were attenuated by nicardipine, but not verapamil. Nicardipine also mitigated caspase-1 activation, inhibited ASC oligomerization, and reduced NLRP3 expression. Furthermore, nicardipine downregulated phosphorylation or nuclear translocation of NF-kappaB p65, consistent with the inhibitory effect of nicardipine on LPS-induced TLR4 expression. In conclusion, nicardipine exerted anti-inflammatory effects through inhibiting NLRP3 inflammasome pathway. Nicardipine may mitigate NLRP3 priming via inhibiting NF-kappaB activation, mediated by suppressing LPS-induced TLR4 expression. [ABSTRACT FROM AUTHOR]

Mastitis is one of the most common diseases that both affects human and animals. Morin is derived from the member of Moraceae family, which has been used in the treatment of many inflammatory diseases. The purpose of this study was to test the protective effect of morin on LPS-induced mastitis and to clarify the possible mechanism. In vivo, the mastitis model was established by lipopolysaccharide (LPS), and morin was treated 1 h before stimulation of LPS. In vitro, peritoneal macrophages were used to test the regulation mechanisms of morin on mastitis. The inflammatory cytokines (TNF-α, IL-1β, and IL-6) was tested by ELISA. Myeloperoxidase (MPO) activity was measured by MPO kit. The expression of NLRP3 inflammasome and NF-κB signaling pathway proteins were detected by western blotting. The results showed that morin alleviated the pathological damage of mammary gland tissues, MPO activity, and the production of TNF-α, IL-1β, and IL-6 in mammary gland tissues. In vitro, morin significantly suppressed the production of inflammatory cytokines. In addition, it also inhibited the activation of NLRP3 inflammasome and NF-κB signaling pathway induced by LPS. In conclusion, the present study suggested that the protective effect of morin against LPS-induced mastitis may be due to its ability to inhibit NLRP3 inflammasome expression and NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is a kind of lung serious disease which leads to the damage of alveolar epithelial cells and capillary endothelial. Lipopolysaccharide (LPS) is one of the common factors inducing ALI. The previous study has reported that the anti-inflammatory effect of peiminine, but little is known about its effect on the ALI induced by LPS. The aim of this study is to investigate the therapeutic effect of peiminine on LPS-induced acute lung injury and potential mechanisms. Mice were given LPS through nasal cavity to establish ALI model, and then the peiminine (1, 3, or 5 mg/kg) was injected into the mice as the experimental group. In the present study, we would measure the W/D ratio, activity of MPO, the histopathological changes, and the levels of cytokines. The results showed that peiminine could reduce the W/D ratio and the MPO activity significantly. Furthermore, the histopathological changes and the expression of TNF-α, IL-1β, and IL-6 were inhibited after the peiminine treatment. In vitro, peiminine significantly inhibited LPS-induced IL-8 production in A549 lung epithelial cells. Meanwhile, the activity of NF-κB signaling pathway was suppressed obviously by peiminine with the western blot analysis. Also, peiminine significantly attenuated LPS-induced AKT and PI3K phosphorylation. In addition, peiminine was found to disrupt lipid rafts formation by attenuating the cholesterol content. In conclusion, peiminine could attenuate LPS-induced ALI in mice and it may become a new approach to treat ALI. [ABSTRACT FROM AUTHOR]

The aim of this article is to study the effect of miR-486-5p in acute lung injury (ALI). MiR-486-5p expression in peripheral blood was determined in ALI patients and healthy volunteers by qRT-PCR. ALI mouse model were reproduced by LPS treatment, and miR-486-5p NC and miRNA-486 inhibitors were injected through trachea. ALI patients' peripheral blood and LPS-induced acute lung injury in mice had significantly higher miR-486-5p levels than control subjects. Inhibition of miR-486-5p by injection with antagomiR-486-5p markedly reduced LPS-induced lung inflammation. Moreover, knockdown of miR-486-5p can reduce protects A549 cell against LPS-induced injury and its corresponding inflammatory response. In addition, Mechanistic analysis indicated that miR-486-5p on the occurrence of ALI is related to the inhibition of OTUD7B activity, which induces the downregulation of inflammatory in ALI. Our results identified miR-486-5p independently associated with ALI. miR-486-5p can mediate the formation of ALI by promoting inflammation. [ABSTRACT FROM AUTHOR]

Esculetin, a coumarin derivative from various natural plants, has an anti-inflammatory property. In the present study, we examined if esculetin has any salutary effects against lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. Acute lung injury (ALI) was induced via the intratracheal administration of LPS, and esculetin (20 and 40 mg/kg) was given intraperitoneally 30 min before LPS challenge. After 6 h of LPS administration, lung tissues were collected for analysis. Pretreatment with esculetin significantly attenuated histopathological changes, inflammatory cell infiltration, and production of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, in the lung tissue. Furthermore, esculetin inhibited the protein kinase B (AKT), extracellular signal-regulated kinase (ERK), and nuclear factor-kappa B (NF-κB) pathways and downregulated the expression of RORγt and IL-17 in LPS-induced ALI. Our results indicated that esculetin possesses anti-inflammatory and protective effects against LPS-induced ALI via inhibition of the AKT/ERK/NF-κB and RORγt/IL-17 pathways. [ABSTRACT FROM AUTHOR]

Lipopolysaccharide (LPS), known as lipoglycans and endotoxins found in the cell wall of some type of Gram-negative bacteria, causes acute lung inflammation (ALI). p-Coumaric acid (p-CA) possesses anti-inflammatory and anti-oxidative activities. The main purpose of our research was to explore the effect of p-CA on LPS-induced inflammation. In part I, 32 rats were divided into four groups: Control, LPS (5 mg/kg), p-CA (100 mg/kg), and LPS + p-CA to investigate acute lung inflammation caused by LPS. In part II, the effect of LPS-stimulated inflammatory response on A549 cells was investigated. The dosage of LPS and p-CA which used in this part was 1 μg/ml and 20 mM, respectively. ALI rats showed an elevation in antioxidant activity, TNF-alpha, IL-6, MDA, inflammatory parameters, and Nrf2 gene expression. Although pre-treatment with p-CA could return these changes approximately to normal condition in all two-part studies (in vivo and in vitro). The results of in vivo and in vitro study showed that LPS induced lung inflammation. Pre-treatment with p-CA causes modulating of oxidative stress in inflammatory condition in lung injury and A549 cell. [ABSTRACT FROM AUTHOR]

Sepsis-induced central nervous system damage is called sepsis-associated encephalopathy (SAE). In addition to neuroinflammation, oxidative stress and apoptosis act in the development of SAE. In the current study, we evaluated the protective effects of lacosamide (LCM) on neuroinflammation induced by lipopolysaccharide (LPS). Twenty-four Wistar albino rats were divided into 3 groups as controls, LPS group (5 mg/kg i.p.), and LPS plus LCM group (5 mg/kg i.p and 40 mg/kg i.p, respectively). In the rat brain, LPS-induced tissue damage was revealed histopathologically as hyperemia and microhemorrhages. LCM pretreatment ameliorated these histopathological changes. LPS decreased brain TAS levels and significantly increased MDA, CRP, HSP, IL-1β, and TNF-α expressions in the cortex, hippocampus, and cerebellum. Western analysis revealed increased brain tissue levels of TNF-α, NF-Kβ, and caspase-3 following LPS. Prophylactic LCM treatment reversed these parameters including oxidative stress, inflammation, and apoptosis in the cortex, hippocampus, and cerebellum. [ABSTRACT FROM AUTHOR]

The aims of this study were to investigate the effect of Hsp27 on LPS-induced inflammation and identify the precise mechanisms about how Hsp27 regulates LPS-induced TLR4 signaling in Thp1 cells. Thp1 cells were transfected with Flag-Hsp27 or pcDNA3.1, and then treated with LPS for indicated time. TNF-α, IL-1β, and IL-6 were determined by ELISA. The protein levels of Hsp27, p-Hsp27 (Ser15, Ser78, and Ser82), and TLR4 were measured by Western blotting. In vitro study showed that over-expression of Hsp27 downregulated the release of TNF-α, IL-1β, and IL-6 and suppressed the activation of TLR4 signals after stimulated by LPS. The location of TLR4 and RAB5 was detected by confocal microscopy. Immunoprecipitation was used to determine the ubiquitination and degradation of TLR4 and interaction between Hsp27 and TLR4. Results showed that Hsp27 could promote TLR4 endocytosis and ubiquitination and degradation. Further research revealed that Hsp27 was phosphorylated after LPS, only phosphorylated Hsp27 can interact with TLR4 and inhibit the activation of TLR4 signaling, which was demonstrated by inhibition of Hsp27 phosphorylation with inhibitors or transfection of Hsp27 mutants into Thp1 cells. Phosphorylated Hsp27 reduced the release of TNF-α, IL-1β, and IL-6, and suppressed the activation of TLR4 signaling by promoting TLR4 endocytosis, ubiquitination, and degradation. [ABSTRACT FROM AUTHOR]

Injury to podocytes leads to proteinuria, a hallmark of most glomerular diseases as well as being associated with the progression of kidney disease. Activation of the Wnt/β-catenin pathway is associated with the pathogenesis of podocyte dysfunction and can play a role in renal injury. Furthermore, the expression of fractalkine (FKN) induced by lipopolysaccharides (LPS) is also one of crucial inflammation factors closely related to renal tissue damage. The aim of this study is to explore the mechanism of LPS-induced FKN expression leading to podocyte injury and contribute to acute kidney injury (AKI) through regulation of Wnt/β-catenin pathway. An AKI model was established for in vivo experiments and blood was collected for serum BUN and Cr measurement, and histopathological features of the kidneys were studied by PASM and IHC staining. For in vitro experiments, a mouse podocyte cell line was stimulated with different concentrations of LPS for 24 and 48 h after which podocyte viability and apoptosis of cells were evaluated. The expression of podocyte-specific markers, FKN and Wnt/β-catenin pathway mRNA and protein was detected in mice and cells by using qRT-PCR and western blotting. LPS induced the expression of FKN and activation of the Wnt/β-catenin pathway, leading to a decrease of podocyte-specific proteins which resulted in poor renal pathology and dysfunction in the AKI mouse model. Moreover, LPS treatment significantly decreased cell viability and induced podocyte apoptosis in a dose-dependent manner that causes changes in the expression of podocyte-specific proteins through activation of FKN and the Wnt/β-catenin pathway. Thus, the expression of FKN and Wnt/β-catenin pathway by LPS is closely associated with podocyte damage or loss and could therefore account for progressive AKI. Our findings indicate that LPS induce podocyte injury and contribute to the pathogenesis of AKI by upregulating the expression of FKN and Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Macrophages play a fundamental role in human chronic diseases such as rheumatoid arthritis, atherosclerosis, and cancer. In the present study, we demonstrated that dual-specificity phosphatase 6 (DUSP6) was upregulated by lipopolysaccharide (LPS) treatment of macrophages. (E/Z)-BCI hydrochloride (BCI) functions as a small molecule inhibitor of DUSP6, and BCI treatment inhibited DUSP6 expression in LPS-activated macrophages. BCI treatment inhibited LPS-triggered inflammatory cytokine production, including IL-1β and IL-6, but not TNF-α, and also affected macrophage polarization to an M1 phenotype. In addition, BCI treatment decreased reactive oxygen species (ROS) production and significantly elevated the levels of Nrf2. Interestingly, pharmacological inhibition of DUSP6 attenuated LPS-induced inflammatory responses was independent of extracellular signal-regulated kinase (ERK) signaling. Furthermore, BCI treatment inhibited phosphorylation of P65 and nuclear P65 expression in LPS-activated macrophages. These results demonstrated that pharmacological inhibition of DUSP6 attenuated LPS-induced inflammatory mediators and ROS production in macrophage cells via activating the Nrf2 signaling axis and inhibiting the NF-κB pathway. These anti-inflammatory effects indicated that BCI may be considered as a therapeutic agent for blocking inflammatory disorders. [ABSTRACT FROM AUTHOR]

Endometritis is a common inflammatory disease which endangers human and animal reproductive health. MicroRNA (miRNA) let-7c plays an important role in the inflammatory process; however, the regulatory underlying mechanism of let-7c in endometritis is unclear. In this study, we confirmed that let-7c was significantly reduced in LPS-induced mouse endometritis model, and overexpression of let-7c was able to effectively reduce uterine tissue damage caused by lipopolysaccharide (LPS), and then, a LPS-induced bovine endometrial epithelial cell (BEND) line was used to mimic the inflammatory model in vitro. Our data showed that overexpression of let-7c significantly reduced the expression of pro-inflammatory cytokines in BEND cells induced by LPS. Meanwhile, immunofluorescence and western blotting results showed that let-7c significantly inhibited LPS-induced phosphorylation of NF-κB, thereby inhibiting downstream pro-inflammatory cytokine expression. Taken together, our results suggested that let-7c ameliorates LPS-induced endometritis by attenuating the expression of pro-inflammatory cytokines via inhibition of the activation of NF-κB. [ABSTRACT FROM AUTHOR]

Bacterial lipopolysaccharide (LPS) induces inflammatory response via toll-like receptor 4 (TLR4). However, this response must be strictly regulated because unbalanced overproduction of pro-inflammatory cytokines can lead to tissue damage and even be fatal. Herein, we explore whether Mer receptor tyrosine kinase (MerTK) regulates Escherichia coli (E. coli) LPS-induced inflammation and mediates phagocytosis of E. coli by macrophages. The results showed that LPS activated TLR4 signaling pathway and induced MerTK pathway in RAW264.7 macrophages, including suppressor of cytokine signaling1 (SOCS1). Preincubation with MerTK-specific blocking antibody (MerTK-Ab) markedly suppressed LPS-induced expression of phosphorylated MerTK, while further promoted LPS-induced production of TNF-α, IL-6, and IL-1β as well as phosphorylation of IκB-α and p65. Likewise, MerTK-Ab prevented LPS-induced SOCS1 expression. Furthermore, LPS-induced production of pro-inflammatory cytokines and activation of NF-κB were increased by transfection with SOCS1 siRNA. Additionally, we demonstrated that MerTK was dispensable in phagocytosis of E. coli by RAW264.7 or peritoneal macrophages. Collectively, these results indicate that MerTK downregulates LPS-induced inflammation through SOCS1 protein without affecting phagocytosis of E. coli in macrophages. [ABSTRACT FROM AUTHOR]

The oxysterone α-mangostin is isolated from mangosteen husks and is widely used in the treatment of abdominal pain, diarrhea, and dysentery. In this study, we established a lipopolysaccharide (LPS)-induced inflammatory model of rat intestinal epithelial cells (IEC-6 cells), at the same time we used differently concentration α-mangostin to detect its anti-inflammatory activity. We applied doses of α-mangostin (2.5, 5, and 10 μM) and detected apoptosis by flow cytometry, and the Griess reagent and the enzyme-linked immunosorbent assay (ELISA) method detected inflammatory factors such as nitric oxide (NO), prostaglandin (PG) E2, interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. We also used quantitative real-time PCR (Q-PCR) to examine inflammatory factors and western blotting to examine the activation of transforming growth factor-activated kinase (TAK)-1-nuclear factor (NF)-κB signaling pathway-related proteins. Finally, we used laser confocal microscopy to detect the effect of the 10 μM α-mangostin on the nuclear import of NF-κB-p65. The results showed that α-mangostin treatment significantly reduced the apoptosis of LPS-stimulated IEC-6 cells, the production of inflammatory factors, the activation of TAK1-NF-κB signaling pathway-related proteins, and the entry of p65 into the nucleus. In conclusion, α-mangostin exerts its anti-inflammatory effects by inhibiting the activation of TAK1-NF-κB and it may be a potential choice for the treatment of inflammation diseases. [ABSTRACT FROM AUTHOR]

Arctiin is a lignin isolated from Arctium lappa which has been known to have anti-viral and anti-inflammatory effects. The aim of this study is to explore the protective effect of arctiin on lipopolysaccharide (LPS)-induced inflammatory responses in acute lung injury (ALI) model of mice. Male BALB/c mice were pretreated with commercial arctiin (10, 20, and 40 mg/kg) 1 h prior to LPS challenge. Twelve hours later, airway inflammation was assessed. We assessed the effects of arctiin on the LPS-induced production of TNF-α, IL-6, and IL-1β in the bronchoalveolar lavage fluid (BALF). The lung wet-to-dry weight ratio, myeloperoxidase (MPO) activity, and inflammatory signaling pathway were also detected. Our results showed that arctiin not only significantly ameliorated LPS-stimulated lung histopathological changes but also reduced the lung MPO activity. Arctiin also dramatically decreased the production of TNF-α, IL-1β, and IL-6 in the BALF. In addition, arctiin significantly inhibited LPS-induced PI3K/Akt phosphorylation as well as NF-κB activation. In conclusion, our results suggested that arctiin protected against LPS-induced ALI through inhibiting PI3K/AKT/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Endotoxin shock is a life-threatening response caused by a disordered immune response to an infection. MDSCs are accumulated and play a protective role in the pathogenesis of endotoxin shock. However, the regulation of MDSCs by small molecule remains unrevealed. Here, we report that arctigenin, a small molecule extracted from Arctium lappa, induces accumulation of functional MDSCs. Arctigenin was able to ameliorate LPS-induced inflammation through accumulating MDSCs, especially granulocytic MDSCs (G-MDSCs), and enhancing the immunosuppressive function of MDSCs in vivo and in vitro. Mechanistically, arctigenin promoted the accumulation of MDSCs through upregulating miR-127-5p which targets the 3′UTR of interferon regulatory factor-8 (IRF8) mRNA. In addition, arctigenin enhanced the immunosuppressive activity of MDSCs on M1 macrophage polarization by elevating the expression of arginase 1 (Arg-1) and inducible nitric oxide synthase (iNOS). Our study provides new insights into the regulation of functional MDSCs by arctigenin in exerting immune responses and pathogenesis of inflammatory diseases. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the inhibition neuroinflammation mechanisms of hyperbaric oxygen therapy (HBOT). Primary astrocytes were incubated with lipopolysaccharide (LPS) after which they underwent HBOT and separate administration of inflammatory cytokine inhibitors. The respective expression of inflammatory factors was then detected. Results showed that LPS significantly induced increases in the expression levels of chemokine (C-X-C motif) ligand 1 (CXCL1), chemokine C-C motif ligand 2 (CCL2), phospho-nuclear factor-kappa B (p-NF-κB), phospho-c-Jun N-terminal kinase (p-JNK), phospho-extracellular signal-regulated kinase (p-ERK), and phospho-p38 (p-p38) in cultured astrocytes and peaked at 3 h. HBOT downregulated the expression of some inflammation mediators including CXCL1 and CCL2. Furthermore, HBOT inhibited the expression of some up-stream regulators of inflammation mediators including p-NF-κB, p-JNK, p-p38 (at 3 and 6 h), and p-ERK (3 h). Inhibitors of NF-κB, ERK, and JNK (BAY117082, PD98059, and SP600125) significantly suppressed the expression of CXCL1 and CCL2 that were induced by LPS for 3 h. However, the p38 inhibitor, SB203580, had no obvious effect on expression levels of CXCL1 and CCL2. In conclusion, we found that HBOT inhibits neuroinflammation via regulation of the LPS-induced NF-κB/mitogen-activated protein kinases (MAPKs, JNK, and ERK) -CCL2/CXCL1 signaling pathways. [ABSTRACT FROM AUTHOR]

Terpinen-4-ol, the major constituent of tea tree oil, has been reported to have anti-inflammatory effect. However, whether terpinen-4-ol could attenuate LPS-induced inflammation in lung tissues remains unclear. In the present study, we aimed to investigate the protective effects of terpinen-4-ol on LPS-induced acute lung injury (ALI) in mice. Terpinen-4-ol could inhibit LPS-induced ALI as confirmed by the decreased lung histopathological changes, MPO activity, and lung W/D ratio caused by terpinen-4-ol. The production of TNF-α and IL-1β in the BALF was suppressed by the treatment of terpinen-4-ol. Western blot analysis showed that terpinen-4-ol significantly attenuated LPS-induced phosphorylation of IκBα and NF-κB p65. Furthermore, the expression of PPAR-γ was dose-dependently upregulated by the treatment of terpinen-4-ol. In conclusion, the results of this study indicated that terpinen-4-ol inhibited LPS-induced ALI via activating PPAR-γ, which subsequently attenuated LPS-induced NF-κB activation and inflammatory response. [ABSTRACT FROM AUTHOR]

Saikosaponin A (SSA) is the major triterpenoid glycoside isolated from Bupleurum falcatum. In this study, we reported the protective effects and mechanism of SSA on lipopolysaccharide (LPS)-induced endometritis in mice. The pathological changes and myeloperoxidase (MPO) activity of uterus tissues were evaluated by hematoxylin and eosin (H&E) staining and MPO detection kit. Inflammatory cytokines TNF-α, IL-1ß, and IL-6 production were detected by ELISA. The expression of protein was measured by western blot analysis. The results showed that SSA administration inhibited inflammatory cell infiltration as confirmed by the decreased MPO activity. LPS-induced uterus histological changes were also suppressed by SSA. Meanwhile, LPS-induced TNF-α, IL-1ß, and IL-6 production were reduced by SSA administration. The phosphorylation levels of nuclear factor kappa B (NF-κB) and inhibitor of kappa B (IκBα) induced by LPS were inhibited by SSA. In addition, the expression of nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase (HO-1) were upregulated by SSA in a concentration-dependent manner. These results provide evidence that SSA protects against LPS-induced endometritis through inhibiting inflammatory response. SSA may be used as a potential therapeutic agent for the treatment of endometritis. [ABSTRACT FROM AUTHOR]

Isoliquiritigenin (ILG), a major ingredient of licorice, has been reported to have anti-oxidative and anti-inflammatory effects. The aim of this study was to investigate the protective effects of ILG on lung injury using an animal model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). Male BALB/c mice were conditioned with ILG 1 h before intranasal instillation of LPS. The effects of ILG on lung injury were assessed by measuring lung histopathological examination, MPO assay, wet/dry (W/D) ratio, and inflammatory cytokine production. The results showed that ILG significantly inhibited LPS-induced lung histopathological changes and the MPO activity. Meanwhile, it attenuated the wet/dry (W/D) ratio in the lung tissues. The results also indicated that ILG inhibited LPS-induced ALI in the expression of inflammatory cytokines in the BALF. Furthermore, ILG can decrease the activity of NF-κB and can increase the expression of PPAR-γ. These findings suggested that ILG inhibited the inflammatory of LPS-induced lung injury by activating PPAR-γ and inhibiting NF-κB activation. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is a serious disease with morbidity and mortality in patients. Engeletin (dihydrokaempferol 3-rhamnoside) is a flavanonol glycoside. It can be found in the skin of white grapes and white wine and is widely distributed in southeast Asia. In our study, we evaluated the protective and therapeutic effects of engeletin on lipopolysaccharide (LPS)-induced ALI in animal model. We determined the level of peroxisome proliferator-activated receptor-γ (PPAR-γ), nuclear factor kappaB (NF-κB), and IκBα by western blotting. The myeloperoxidase (MPO) activity and lung wet/dry (W/D) ratio in lung tissues were also detected. Histopathological changes and the pro-inflammatory cytokines TNF-α, IL-6, and IL-1β were determined by H&E staining and ELISA. The MPO activity and lung W/D ratio induced by LPS were attenuated by engeletin. The numbers of inflammatory cells and the levels of inflammatory cytokines in bronchoalveolar lavage fluid (BALF) were ameliorated by engeletin. Furthermore, the results also showed that engeletin significantly suppressed LPS-induced NF-κB activation. The expression of PPAR-γ was upregulated by treatment of engeletin. In conclusion, we found that engeletin had protective and therapeutic effects against LPS-induced ALI by activating PPAR-γ. Engeletin is a potentially effective agent for the treatment of lung injury. [ABSTRACT FROM AUTHOR]

Quercetin (Que) as an abundant flavonol element possesses potent antioxidative properties and has protective effect in lipopolysaccharide (LPS)-induced acute lung injury (ALI), but the specific mechanism is still unclear, so we investigated the effect of Que from in vivo and in vitro studies and the related mechanism of cAMP-PKA/Epac pathway. The results in mice suggested that Que can inhibit the release of inflammatory cytokine, block neutrophil recruitment, and decrease the albumin leakage in dose-dependent manners. At the same time, Que can increase the cAMP content of lung tissue, and Epac content, except PKA. The results in epithelial cell (MLE-12) suggested that Que also can inhibit the inflammatory mediators keratinocyte-derived chemokines release after LPS stimulation; Epac inhibitor ESI-09 functionally antagonizes the inhibitory effect of Que; meanwhile, PKA inhibitor H89 functionally enhances the inhibitory effect of Que. Overexpression of Epac1 in MLE-12 suggested that Epac1 enhance the effect of Que. All those results suggested that the protective effect of quercetin in ALI is involved in cAMP-Epac pathway. [ABSTRACT FROM AUTHOR]

Nobiletin (NOB), a citrus polymethoxy flavonoid, has been reported to exhibit anti-inflammatory, anti-cancer, and anti-insulin resistance activities. Although the anti-inflammatory activity of NOB already reported, its involvement in lung protection has not been reported. Thus, this study aimed to investigate the anti-inflammatory response of NOB in lipopolysaccharide (LPS)-stimulated A549 cells and LPS-induced acute lung injury (ALI) in mice. The animals were pre-treated with NOB (5, 10, and 20 mg/kg) or DEX (5 mg/kg) at 12 and 1 h before intranasal instillation of LPS. The severity of pulmonary injury was evaluated 6 h after LPS administration. Results suggested that treatment with NOB dramatically attenuated lung histopathological changes, wet-to-dry (W/D) ratio, myeloperoxidase (MPO) activity, the numbers of inflammatory cells, and TNF-α, IL-6, and NO in BALF induced by LPS. Furthermore, NOB also significantly inhibited the expression of iNOS and the phosphorylation of NF-κBp65 and IκBα. In vitro, NOB inhibited NF-κB activation and TNF-α, IL-6 production in LPS-stimulated A549 cells. Taken together, these results indicated that NOB exhibited a protective effect on ALI, and the possible mechanism is involved in inhibiting NF-κB activation, subsequently inhibiting LPS-induced inflammatory response. [ABSTRACT FROM AUTHOR]

Fibroblast growth factor 21 (FGF-21) has been previously judged as a major metabolic regulator. In this paper, we show that FGF-21 has a potential role in anti-inflammation and immunoregulation. In vivo, treatment with exogenous FGF-21 can alleviate LPS-induced inflammation. In vitro, FGF-21 inhibited LPS-induced IL-1β expression in THP-1 cells. Furthermore, besides the NF-κB pathway, the mechanism of action of FGF-21 was observed to involve the elevation of IL-10 in the ERK1/2 pathway. This study clearly indicates that FGF21 can be used as an attractive target for the management of inflammatory disorders. This piece of research indicates that FGF-21 could have much value in the management of inflammatory disorders. [ABSTRACT FROM AUTHOR]

Rosmarinic acid (RA), a type of food additives mainly extracted from rosemary, has been reported to possess anti-inflammatory activities in some previous studies. However, the effects of RA on lipopolysaccharide (LPS)-induced mastitis have not been reported. Here, we investigated the anti-inflammatory effects of RA on LPS-induced mastitis in mice and elucidated the potential mechanisms in mouse mammary epithelial cells (mMECs). RA treatment significantly ameliorated the mammary structural damage, and reduced the activity of myeloperoxidase. ELISA and qPCR results indicated that RA dose-dependently decreased the expression of TNF-α, IL-1β, and IL-6 both in tissues and mMECs. Furthermore, RA remarkably suppressed the protein levels of TLR4, MyD88, IRAK1, TRAF6, and p-IKKβ. In addition, RA was also found to inhibit LPS-induced NF-κB signaling pathway activation. These results suggest that RA effectively attenuates LPS-induced mastitis by inhibiting the TLR4/MyD88/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the protective effects of Saikosaponin a (SSa), a triterpene saponin derived from Radix bupleuri, on lipopolysaccharide (LPS)-induced acute lung injury (ALI) using a murine model. The mice were given SSa 1 h after intranasal instillation of LPS. Then, lung histopathological examination, the wet/dry (W/D) ratio, myeloperoxidase (MPO), and inflammatory cytokines in bronchoalveolar lavage fluid (BALF) were detected in this study. The results showed that SSa reduced lung pathological injury induced by LPS. Furthermore, LPS-induced lung W/D ratio, MPO activity, and inflammatory cytokines TNF-α and IL-1β in BALF were significantly inhibited by SSa. In addition, SSa suppressed LPS-induced NF-κB activation and NLRP3 inflammasome expression. In conclusion, we found that SSa played a critical anti-inflammatory effect through inhibition of NF-κB and NLRP3 signaling pathways and protected against LPS-induced ALI. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the effects of salidroside (Sal) on lung injury in lipopolysaccharide (LPS)-induced endotoxemic in vitro and in vivo. SD rats were randomly divided into five groups: control group, LPS group (15 mg kg), LPS plus dexamethasone (2 mg kg), and LPS plus Sal groups with different Sal doses (20 mg kg, 40 mg kg). Wet-to-dry weight (W/D) ratio was performed. Hematoxylin-eosin (HE) staining of lung was performed. Lung level of myeloperoxidase (MPO) was measured. Serum levels of the activities of the anti-oxidant superoxide dismutase (SOD), glutathione peroxidase (GSH-px), glutathione (GSH), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) were measured. Caveolin-1 and TLR/NF-κB pathway proteins were detected by Western blot. In vitro, we evaluated the protective effect of Sal on A549 cell line induced by LPS. The activities of the antioxidant SOD, CAT, GSH and GPX, TNF-α, IL-6, and IL-1β in cellular supernatant were measured. Caveolin-1 and TLR/NF-κB pathway was examined by Western blot. As a result, Sal significantly attenuated the above indices. In addition, Sal exerts pronounced protective effects in rats subjected to LPS possibly through inhibiting the caveolin-1 and TLR/NF-κB pathway in vivo. Our results indicated that Sal could be a potential therapeutic agent for the treatment of lung injury disease. [ABSTRACT FROM AUTHOR]

Cigarette smoking is a major risk factor for several human diseases. Chronic inflammation, resulting from increased oxidative stress, has been suggested as a mechanism that contributes to the increased susceptibility of smokers to cancer and microbial infections. We have previously shown that whole-smoke conditioned medium (WS-CM) and total particulate matter (TPM) prepared from Kentucky 3R4F reference cigarettes [collectively called as combustible tobacco product preparations (TPPs)] potently suppressed agonist-stimulated cytokine secretion and target cell killing in peripheral blood mononuclear cells (PBMCs). Here we have investigated the role of oxidative stress from TPPs, which alters inflammatory responses in vitro. Particularly, we investigated the mechanisms of WS-CM-induced suppression of select cytokine secretions in Toll-like receptor (TLR) agonist-stimulated cells and target cell killing by effector cells in PBMCs. Pretreatment with N-acetyl cysteine (NAC), a precursor of reduced glutathione and an established anti-oxidant, protected against DNA damage and cytotoxicity caused by exposure to WS-CM. Similarly, secretion of tumor necrosis factor (TNF), interleukin (IL)-6, and IL-8 in response to TLR-4 stimulation was restored by pretreatment with NAC. Target cell killing, a functional measure of cytolytic cells in PBMCs, is suppressed by WS-CM. Pretreatment with NAC restored the target cell killing in WS-CM treated PBMCs. This was accompanied by higher perforin levels in the effector cell populations. Collectively, these data suggest that reducing oxidative stress caused by cigarette smoke components restores select immune responses in this ex vivo model. [ABSTRACT FROM AUTHOR]

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infection (LRTI) in children under 5 years of age, especially infants with severe bronchiolitis. Our preliminary clinical experiments showed that bacterial colonization was commonly observed in children with virus-induced wheezing, particularly in those with recurrent wheezing, suggesting that bacterial colonization with an accompanying viral infection may contribute to disease severity. In most cases, RSV-infected infants were colonized with pathogenic bacteria (mainly Gram-negative bacteria). LPS is the main component of Gram-negative bacteria and acts as a ligand for Toll-like receptor 4 (TLR4). Relevant studies have reported that the TLR family is crucial in mediating the link between viral components and immunologic responses to infection. Of note, TLR4 activation has been associated with disease severity during RSV infection. In the present study, we identified that LPS aggravated RSV-induced AHR and airway inflammation in BALB/c mice using an RSV coinfection model. We found that the airway inflammatory cells and cytokines present in BALF and TRIF in lung tissue play a role in inducing AHR and airway inflammation upon RSV and bacteria coinfection, which might occur through the TRIF-MMP-9-neutrophil-MMP-9 signalling pathway. These results may aid in the development of novel treatments and improve vaccine design. [ABSTRACT FROM AUTHOR]

Citral is a mixture of the two monoterpenoid isomers (neral and geranial) widely used as a health-promoting food additive safe for human and animal (approved by the US Food and Drug Administration). In vitro studies have reported on the capability of citral to reduce inflammation. Here, we report antipyretic effects of citral in vivo using the most well-accepted model of sickness syndrome, i.e., systemic administration of () to rats. Citral given by gavage caused no change in control euthermic rats (treated with saline) but blunted most of the assessed parameters related to the sickness syndrome [fever (hallmark of infection), plasma cytokines (IL-1β, IL-6, and TNF-α) release, and prostaglandin E (PGE) synthesis (both peripherally and hypothalamic)]. Moreover, LPS caused a sharp increase in plasma corticosterone levels that was unaltered by citral. These data are consistent with the notion that citral has a corticosterone-independent potent antipyretic effect, acting on the peripheral febrigenic signaling (plasma levels of IL-1β, IL-6, TNF-α, and PGE), eventually down-modulating hypothalamic PGE production. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is characterized by widespread inflammation in the lungs and alveolar-capillary destruction, causing high morbidity and mortality. Cavidine, isolated from Corydalis impatiens, have been exhibited to have potent anti-inflammatory effects in previous studies. The purpose of this study was to evaluate the protective effect of cavidine on lipopolysaccharide (LPS)-induced ALI and to enunciate the underlying in vivo and in vitro mechanisms. Mice were intraperitoneally administrated with cavidine (1, 3, or 10 mg/kg) at 1 and 12 h, prior to the induction of ALI by intranasal administration of LPS (30 mg/kg). Blood samples, lung tissues, and bronchoalveolar lavage fluid (BALF) were harvested after LPS challenge. Furthermore, we used LPS-induced lung epithelial cells A549 to examine the mechanism of cavidine to lung injury. The results showed that pretreatment with cavidine significantly decreased lung wet-to-dry weight (W/D) ratio, reduced pro-inflammatory cytokine levels including TNF-α and IL-6 in BALF and serum from LPS-stimulated mice, and attenuated lung histopathological changes. In addition, western blot results showed that cavidine inhibited the phosphorylation of nuclear factor-kappaB (NF-κB) p65 and IκBα induced by LPS. In conclusion, our results demonstrate that cavidine protects against LPS-induced acute lung injury in mice via inhibiting of pro-inflammatory cytokine TNF-α and IL-6 production and NF-κB signaling pathway activation. Taken together, cavidine may be useful for the prevention and treatment of pulmonary inflammatory diseases, such as ALI. [ABSTRACT FROM AUTHOR]