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Acute respiratory distress syndrome (ARDS) is characterized by dysregulated inflammation and increased permeability of lung microvascular cells. CD26/dipeptidyl peptidase-4 (DPP4) is a type II membrane protein that is expressed in several cell types and mediates multiple pleiotropic effects. We previously reported that DPP4 inhibition by sitagliptin attenuates lipopolysaccharide (LPS)-induced lung injury in mice. The current study characterized the functional role of CD26/DPP4 expression in LPS-induced lung injury in mice, isolated alveolar macrophages, and cultured lung endothelial cells. In LPS-induced lung injury, inflammatory responses [bronchoalveolar lavage fluid (BALF) neutrophil numbers and several proinflammatory cytokine levels] were attenuated in Dpp4 knockout (Dpp4 KO) mice. However, multiple assays of alveolar capillary permeability were similar between the Dpp4 KO and wild-type mice. TNF-α and IL-6 production was suppressed in alveolar macrophages isolated from Dpp4 KO mice. In contrast, in cultured mouse lung microvascular endothelial cells (MLMVECs), reduction in CD26/DPP4 expression by siRNA resulted in greater ICAM-1 and IL-6 expression after LPS stimulation. Moreover, the LPS-induced vascular monolayer permeability in vitro was higher in MLMVECs treated with Dpp4 siRNA, suggesting that CD26/DPP4 plays a protective role in endothelial barrier function. In summary, this study demonstrated that genetic deficiency of Dpp4 attenuates inflammatory responses but not permeability in LPS-induced lung injury in mice, potentially through differential functional roles of CD26/DPP4 expression in resident cellular components of the lung. CD26/DPP4 may be a potential therapeutic target for ARDS and warrants further exploration to precisely identify the multiple functional effects of CD26/DPP4 in ARDS pathophysiology. NEW & NOTEWORTHY: We aimed to clarify the functional roles of CD26/DPP4 in ARDS pathophysiology using Dpp4-deficient mice and siRNA reduction techniques in cultured lung cells. Our results suggest that CD26/DPP4 expression plays a proinflammatory role in alveolar macrophages while also playing a protective role in the endothelial barrier. Dpp4 genetic deficiency attenuates inflammatory responses but not permeability in LPS-induced lung injury in mice, potentially through differential roles of CD26/DPP4 expression in the resident cellular components of the lung. [ABSTRACT FROM AUTHOR]

Excessive or persistent inflammation may have detrimental effects on lung structure and function. Currently, our understanding of conserved host mechanisms that control the inflammatory response remains incompletely understood. In this study, we investigated the role of type I interferon signaling in the inflammatory response against diverse clinically relevant stimuli. Using mice deficient in type I interferon signaling (IFNAR1−/−), we demonstrate that the absence of interferon signaling resulted in a robust and persistent inflammatory response against Pseudomonas aeruginosa, lipopolysaccharide, and chemotherapeutic agent bleomycin. The elevated inflammatory response in IFNAR1−/− mice was manifested as elevated myeloid cells, such as macrophages and neutrophils, in the bronchoalveolar lavage. The inflammatory cell response in the IFNAR1−/− mice persisted to 14 days and there is impaired recovery and fibrotic remodeling of the lung in IFNAR1−/− mice after bleomycin injury. In the Pseudomonas infection model, the elevated inflammatory cell response led to improved bacterial clearance in IFNAR1−/− mice, although there was similar lung injury and survival. We performed RNA sequencing of lung tissue in wild-type and IFNAR1−/− mice after LPS and bleomycin injury. Our unbiased analysis identified differentially expressed genes between IFNAR1−/− and wild-type mice, including previously unknown regulation of nucleotide-binding oligomerization domain (NOD)-like receptor signaling, retinoic acid-inducible gene-I (RIG-I) signaling, and necroptosis pathway by type I interferon signaling in both models. These data provide novel insights into the conserved anti-inflammatory mechanisms of the type I interferon signaling. NEW & NOTEWORTHY: Type I interferons are known for their antiviral activities. In this study, we demonstrate a conserved anti-inflammatory role of type I interferon signaling against diverse stimuli in the lung. We show that exacerbated inflammatory response in the absence of type I interferon signaling has both acute and chronic consequences in the lung including structural changes. [ABSTRACT FROM AUTHOR]

Bacteriophages are the natural predators of bacteria and are available abundantly everywhere in nature. Lytic phages can specifically infect their bacterial host (through attachment to the receptor) and use their host replication machinery to replicate rapidly, a feature that enables them to kill a disease‐causing bacteria. Hence, phage attachment to the host bacteria is the first important step of the infection process. It is reported in this study that the receptor could be an LPS which is responsible for the attachment of the Sfk20 phage to its host (Shigella flexneri 2a). Phage Sfk20 bacteriolytic activity was examined for preliminary optimization of phage titer. The phage Sfk20 viability at different saline conditions was conducted. The LC–MS/MS technique used here for detecting and identifying 40 Sfk20 phage proteins helped us to get an initial understanding of the structural landscape of phage Sfk20. From the identified proteins, six structurally significant proteins were selected for structure prediction using two neural network systems: AlphaFold2 and ESMFold, and one homology modeling software: Phyre2. Later the performance of these modeling systems was compared using various metrics. We conclude from the available and generated information that AlphaFold2 and Phyre2 perform better than ESMFold for predicting Sfk20 phage protein structures. [ABSTRACT FROM AUTHOR]

Trace elements are cofactors in various enzymes in the antioxidant defense and cell homeostasis required in the tissue during inflammation. In acute kidney injury induced by lipopolysaccharide (LPS), renal cells are affected by cytotoxicity. Renal evacuation and gastrointestinal absorption rates are important in regulating plasma levels of trace elements. Simvastatin is a widely used anti-lipidemic drug with known anti-inflammatory effects. This study aimed to examine the effect of simvastatin on trace elements and electrolyte levels in kidney tissue in rats with LPS-induced sepsis. Adult male Wistar albino rats were divided into four groups: control, LPS (20 mg/kg, i.p., single dose), simvastatin (20 mg/kg, o.p., 5 days), and LPS + Simvastatin (LPS + Sim). Sodium, potassium, calcium, magnesium, selenium, zinc, copper, and histological structural changes were examined in kidney tissue samples 4 h after LPS execution. The inductively coupled plasma optical emission spectroscopy technique (ICP-OES) was used to determine the tissue trace element levels. In rats with sepsis-induced LPS, selenium, calcium, sodium, and magnesium levels significantly decreased while copper, potassium, and zinc levels significantly increased compared to other experimental groups. In sepsis treated with the simvastatin (LPS + Simvastatin) group, trace elements and electrolyte levels are like the control groups, apart from selenium levels. Selenium levels were significantly decreased in the LPS + Simvastatin group compared to the controls. As a result of examining the kidney tissues under a light microscope, simvastatin improved tissue damage caused by LPS-induced acute kidney injury. LPS-induced renal injury and simvastatin caused significant changes in the oxidant/antioxidant system. In septic rats, simvastatin was shown to balance some trace element levels, and it may improve damage in the kidney tissue. [ABSTRACT FROM AUTHOR]

While the excessive inflammation in cancer cachexia is well-known to be induced by the overproduction of inflammatory mediators in the periphery, microflora disruption and brain dysfunction are also considered to contribute to the induction of cancer cachexia. Hypothalamic microglia play a crucial role in brain inflammation and central-peripheral immune circuits via the production of inflammatory mediators. In the present study, we evaluated possible changes in excessive secretion of gut microbiota-derived endotoxin and the expression timeline of several inflammation-regulatory mediators and their inhibiting modulators in hypothalamic microglia of a mouse model of cancer cachexia following transplantation of pancreatic cancer cells. We demonstrated that the plasma level of lipopolysaccharide (LPS) was significantly increased with an increase in anaerobic bacteria, especially Firmicutes, in the gut at the late stage of tumor-bearing mice that exhibited dramatic appetite loss, sarcopenia and severe peripheral immune suppression. At the early stage, in which tumor-bearing mice had not yet displayed "cachexia symptoms", the mRNA expression of pro-inflammatory cytokines, but not of the neurodegenerative and severe inflammatory modulator lipocalin-2 (LCN2), was significantly increased, whereas at the late "cachexia stage", the level of LCN2 mRNA was significantly increased along with significant decreases in levels of inhibitory immune checkpoint receptors programmed death receptor-1 (PD-1) and CD112R in hypothalamic microglia. In addition, a high density of activated neurons in the paraventricular nucleus (PVN) of the hypothalamus region and a significant increase in corticosterone secretion were found in cachexia model mice. Related to the cachexia state, released corticosterone was clearly increased in normal mice with specific activation of PVN neurons. A marked decrease in the natural killer cell population was also observed in the spleen of mice with robust activation of PVN neurons as well as mice with cancer cachexia. On the other hand, in vivo administration of LPS in normal mice induced hypothalamic microglia with low expression of inhibitory immune checkpoint receptors. These findings suggest that the induction of cancer cachexia may parallel exacerbation of the hypothalamic inflammatory status with polarization to microglia expressed with low levels of inhibitory immune checkpoint receptors following LPS release from the gut microflora. [ABSTRACT FROM AUTHOR]

Background: Untargeted metabolomics and proteomics were employed to investigate the intracellular response of yak rumen epithelial cells (YRECs) to conditions mimicking subacute rumen acidosis (SARA) etiology, including exposure to short-chain fatty acids (SCFA), low pH5.5 (Acid), and lipopolysaccharide (LPS) exposure for 24 h. Results: These treatments significantly altered the cellular morphology of YRECs. Metabolomic analysis identified significant perturbations with SCFA, Acid and LPS treatment affecting 259, 245 and 196 metabolites (VIP > 1, P < 0.05, and fold change (FC) ≥ 1.5 or FC ≤ 0.667). Proteomic analysis revealed that treatment with SCFA, Acid, and LPS resulted in differential expression of 1251, 1396, and 242 proteins, respectively (FC ≥ 1.2 or ≤ 0.83, P < 0.05, FDR < 1%). Treatment with SCFA induced elevated levels of metabolites involved in purine metabolism, glutathione metabolism, and arginine biosynthesis, and dysregulated proteins associated with actin cytoskeleton organization and ribosome pathways. Furthermore, SCFA reduced the number, morphology, and functionality of mitochondria, leading to oxidative damage and inhibition of cell survival. Gene expression analysis revealed a decrease the genes expression of the cytoskeleton and cell cycle, while the genes expression associated with inflammation and autophagy increased (P < 0.05). Acid exposure altered metabolites related to purine metabolism, and affected proteins associated with complement and coagulation cascades and RNA degradation. Acid also leads to mitochondrial dysfunction, alterations in mitochondrial integrity, and reduced ATP generation. It also causes actin filaments to change from filamentous to punctate, affecting cellular cytoskeletal function, and increases inflammation-related molecules, indicating the promotion of inflammatory responses and cellular damage (P < 0.05). LPS treatment induced differential expression of proteins involved in the TNF signaling pathway and cytokine-cytokine receptor interaction, accompanied by alterations in metabolites associated with arachidonic acid metabolism and MAPK signaling (P < 0.05). The inflammatory response and activation of signaling pathways induced by LPS treatment were also confirmed through protein interaction network analysis. The integrated analysis reveals co-enrichment of proteins and metabolites in cellular signaling and metabolic pathways. Conclusions: In summary, this study contributes to a comprehensive understanding of the detrimental effects of SARA-associated factors on YRECs, elucidating their molecular mechanisms and providing potential therapeutic targets for mitigating SARA. [ABSTRACT FROM AUTHOR]

Trillions of intestinal bacteria in the human body undergo dynamic transformations in response to physiological and pathological changes. Alterations in their composition and metabolites collectively contribute to the progression of Alzheimer's disease. The role of gut microbiota in Alzheimer's disease is diverse and complex, evidence suggests lipid metabolism may be one of the potential pathways. However, the mechanisms that gut microbiota mediate lipid metabolism in Alzheimer's disease pathology remain unclear, necessitating further investigation for clarification. This review highlights the current understanding of how gut microbiota disrupts lipid metabolism and discusses the implications of these discoveries in guiding strategies for the prevention or treatment of Alzheimer's disease based on existing data. [ABSTRACT FROM AUTHOR]

Macrophage polarization to the M1 spectrum is induced by bacterial cell wall components through stimulation of Toll-like family (TLR) receptors. By orchestrating the expression of relevant mediators of the TLR cascade, as well as associated pathways and feedback loops, macrophage polarization is coordinated to ensure an appropriate immune response. This is central to the successful control of pathogens and the maintenance of health. Macrophage polarization is known to be modulated at both the transcriptional and post-transcriptional levels. In recent years, the miRNA-based post-transcriptional regulation of M1 polarization has received increasing attention from the scientific community. Comparative studies have shown that TLR stimulation alters the miRNA profile of macrophages and that macrophages from the M1 or the M2 spectrum differ in terms of miRNAs expressed. Simultaneously, miRNAs are considered critical post-transcriptional regulators of macrophage polarization. In particular, miRNAs are thought to play a regulatory role in the switch between the early proinflammatory response and the resolution phase. In this review, we will discuss the current state of knowledge on the complex interaction of transcriptional and post-transcriptional regulatory mechanisms that ultimately determine the functionality of macrophages. [ABSTRACT FROM AUTHOR]

Lactoperoxidase systems (LPSs) can enhance the microbiological quality of raw milk when there is lack of cooling facilities. In this study, a total of 250 milk samples were collected from farmers, collectors, and factories. Experimental samples were both LPS-activated morning and overnight milk. The samples were tested with several chemical and microbiological tests, such as total bacterial count (TBC), total coliform count (TCC), and Escherichia coli count (EC). Results indicated that all LPS-activated milk samples had a higher quality than all the control samples. For instance, both the morning and overnight farm milk samples had mean TBCs of 5.79 log and 6.55 log cfu/mL, which is significantly (p < 0.05) lower than the control samples' mean TBC of 6.73 log and 7.31 log cfu/mL, respectively. When this was compared with the Ethiopian Standard, 51.4% of morning and 39.5% of overnight farm milk with LPS activation met the acceptable quality, while only 28% of morning and 15.7% of overnight control milk met the standard. Moreover, LPS activation has also significantly improved the shelf life of collectors' raw milk and pasteurized milk at the factories. Therefore, a better hygienic practice with LPS application can be practiced in conditions that lack cooling infrastructure and electricity. [ABSTRACT FROM AUTHOR]

Introduction: Indole-3-carbinol (I3C) is found in cruciferous vegetables and used as a dietary supplement. It is known to act as a ligand for aryl hydrocarbon receptor (AhR). In the current study, we investigated the role of AhR and the ability of I3C to attenuate LPS-induced Acute Respiratory Distress Syndrome (ARDS). Methods: To that end, we induced ARDS in wild-type C57BL/6 mice, Ccr2gfp/gfp KI/KO mice (mice deficient in the CCR2 receptor), and LyZcreAhRfl/fl mice (mice deficient in the AhR on myeloid linage cells). Additionally, mice were treated with I3C (65 mg/kg) or vehicle to investigate its efficacy to treat ARDS. Results: I3C decreased the neutrophils expressing CXCR2, a receptor associated with neutrophil recruitment in the lungs. In addition, LPS-exposed mice treated with I3C revealed downregulation of CCR2+ monocytes in the lungs and lowered CCL2 (MCP-1) protein levels in serum and bronchoalveolar lavage fluid. Loss of CCR2 on monocytes blocked the recruitment of CXCR2+ neutrophils and decreased the total number of immune cells in the lungs during ARDS. In addition, loss of the AhR on myeloid linage cells ablated I3Cmediated attenuation of CXCR2+ neutrophils and CCR2+ monocytes in the lungs from ARDS animals. Interestingly, scRNASeq showed that in macrophage/monocyte cell clusters of LPS-exposed mice, I3C reduced the expression of CXCL2 and CXCL3, which bind to CXCR2 and are involved in neutrophil recruitment to the disease site. Discussion: These findings suggest that CCR2+ monocytes are involved in the migration and recruitment of CXCR2+ neutrophils during ARDS, and the AhR ligand, I3C, can suppress ARDS through the regulation of immune cell trafficking. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect of sinomenine （SIN） on LPS-induced apoptosis and autophagy of lung epithelial cells through the JNK/c-Jun signaling pathway. Methods: MLE-12 lung epithelial cells were cultured, and the toxicity of SIN was detected by CCK-8. Apoptosis was detected by flow cytometry, the number of autophagosomes was detected by immunofluorescence, and the expression levels of apoptosis, autophagy and JNK/c-Jun signaling pathway-related proteins were detected by Western blot. Results: After LPS modeling, apoptosis rate and the number of autophagosomes were increased, the protein levels of Cleaved caspase-3, Bax, and Beclin-1, and LC3Ⅱ/LC3Ⅰ, p-JNK/JNK and p-c-Jun/c-Jun were increased （P<0.05）; Bcl-2 and P62 protein levels were decreased （P<0.05）. SIN treatment can significantly improve the effects of LPS on apoptosis and autophagy, as well as the regulation of the JNK/c-Jun signaling pathway （P<0.05）. Treatment with the autophagy inhibitor 3-MA or the JNK agonist ANISO could partially reverse the protective effect of SIN on LPS-induced lung epithelial cells （P<0.05）. Conclusion: SIN may increase autophagy and protect lung epithelial cells damaged by LPS by regulating proteins related to the JNK/c-Jun signaling pathway. [ABSTRACT FROM AUTHOR]

Antibiotic resistance has emerged as a grave threat to global public health, leading to an increasing number of treatment failures. Antimicrobial peptides (AMPs) are widely regarded as potential substitutes for traditional antibiotics since they are less likely to induce resistance when used. A novel AMP named Brevinin-1BW (FLPLLAGLAASFLPTIFCKISRKC) was obtained by the Research Center of Molecular Medicine of Yunnan Province from the skin of the Pelophylax nigromaculatus. Brevinia-1BW had effective inhibitory effects on Gram-positive bacteria, with a minimum inhibitory concentration (MIC) of 3.125 μg/mL against Enterococcus faecalis (ATCC 29212) and 6.25 μg/mL against both Staphylococcus aureus (ATCC 25923) and multidrug-resistant Staphylococcus aureus (ATCC 29213) but had weaker inhibitory effects on Gram-negative bacteria, with a MIC of ≥100 μg/mL. Studies using scanning electron microscopy (SEM) and flow cytometry have revealed that it exerts its antibacterial activity by disrupting bacterial membranes. Additionally, it possesses strong biofilm inhibitory and eradication activities as well as significant lipopolysaccharide (LPS)-binding activity. Furthermore, Brevinin-1BW has shown a significant anti-inflammatory effect in LPS-treated RAW264.7 cells. In conclusion, Brevinin-1BW is anticipated to be a promising clinical agent with potent anti-Gram-positive bacterial and anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Fucoidan is a popular polysaccharide known to have important biological functions. In the present research, the therapeutic effect of fucoidan on gastrointestinal illness induced by lipopolysaccharide (LPS) in mice was determined. A total of thirty ICR mice were divided into three groups, including group C, M and Y. Mice in group Y were treated with fucoidan (200 mg/kg b.w.) for 14 days, while mice in groups C and M received normal saline. On day 15, the mice in group M and Y were challenged with LPS @10mg/kg b.w. by intraperitoneal injection. After 24 hours, the mice in all groups were euthanized and different samples were collected for analysis. Results showed that fucoidan decreased the weight loss in mice to a certain degree and alleviated the intestinal damage caused by LPS by improving ratio of villus length/crypt depth, through increasing villus length and decreasing crypt depth in mice. It was established that mice treated with fucoidan had a significantly higher levels of T-AOC (P<0.01), GSH-Px (P<0.001), IL-10 (P<0.001) and SOD (P<0.01) and a significantly lower levels of MDA (P<0.001) and TNF-α (P<0.05), indicating that fuciodan may have protective effect against oxidative damage by LPS. Microbiota analysis revealed that the number and abundance of phyla and genera found in the microbiome of mice in group Y were close to those of mice in group C, indicating that fucoidan may promote the biodiversity of microbiota in mice. Taken together, the fucoidan may have protective effect against intestinal damages in mice by regulating oxidation resistance, inflammatory response and improving microbiota. [ABSTRACT FROM AUTHOR]

Endometriosis is a complex gynecological disease that affects more than 10% of women in their reproductive years. While surgery can provide temporary relief from women's pain, symptoms often return in as many as 75% of cases within two years. Previous literature has contributed to theories about the development of endometriosis; however, the exact pathogenesis and etiology remain elusive. We conducted a preliminary investigation into the influence of primary endometrial cells (ECs) on the development and progression of endometriosis. In vitro studies, they were involved in inducing Lipopolysaccharide (LPS) in rat-isolated primary endometrial cells, which resulted in increased nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) mRNA gene expression (quantitative polymerase chain reaction analysis, qPCR) and protein expression (western blot analysis). Additionally, in vivo studies utilized autogenic and allogeneic transplantations (rat to rat) to investigate endometriosis-like lesion cyst size, body weight, protein levels (immunohistochemistry), and mRNA gene expression. These studies demonstrated that estrogen upregulates the gene and protein regulation of cytoskeletal (CK)-18, transforming growth factor-β (TGF-β), VEGF, and tumor necrosis factor (TNF)-α, particularly in the peritoneum. These findings may influence cell proliferation, angiogenesis, fibrosis, and inflammation markers. Consequently, this could exacerbate the occurrence and progression of endometriosis. [ABSTRACT FROM AUTHOR]

Septic lung injury is characterized by uncontrollable inflammatory infiltrations and acute onset bilateral hypoxemia. Evidence has emerged of the beneficial effect of hydrogen in acute lung injury (ALI), but the underlying mechanism is unclear. In this research, the recovery action of hydrogen on lipopolysaccharide (LPS)-induced ALI in mice and A549 cells was investigated. The 7-day survival rate and body weight of mice were measured after intraperitoneal injection of LPS. Lung function was determined by a whole body plethysmography (WBP) system using the indicators respiratory rate and enhanced pause. Hematoxylin and eosin (HE) staining confirmed the signs of pulmonary edema and inflammatory ooze. Reverse transcription-polymerase chain reaction (RT-PCR) quantification was used to detect the expression of inflammatory factors. Western blotting analysis evaluated the expression levels of involved proteins in the AMP-activated protein kinase (AMPK) pathway. The experimental results confirmed that hydrogen provided an essential solution to the dissipative effects of LPS on survival rate, weight loss and lung function. The LPS-stimulated inflammatory factors, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were also suppressed by hydrogen in A549 cells. Western blot analysis showed that hydrogen significantly upregulated the levels of phosphorylated AMPK (p-AMPK) and lowered the LPS-induced increased expression of dynamin-related protein 1 (Drp1) and Caspase3. These findings prove that hydrogen attenuated LPS-treated ALI by activating the AMPK pathway, supporting the feasibility of hydrogen treatment for sepsis. • Hydrogen could attenuate endotoxin-induced acute lung injury. • The increase of Drp1 after endotoxemia is a compensatory mechanism. • Hydrogen attenuates septic lung injury by bidirectional regulation of Caspase3 after activating AMPK. [ABSTRACT FROM AUTHOR]

Acute liver injury (ALI) is an important medical problem that requires effective therapy. Astaxanthin (AST) is a carotenoid, and the beneficial effects of astaxanthin, including anti-oxidative, anti-inflammatory and anti-tumour activities, have been identified. The present study was designed to elucidate the protective effects of astaxanthin against ALI and their underlying mechanisms. RAW264.7 macrophages were treated with dimethyl sulfoxide combined with different doses of astaxanthin for 12 h. Mice were fed with or without astaxanthin for up to 7 days. LPS was administered to induce inflammation. We assessed histopathology, oxidative stress, inflammation and apoptosis .The results indicated that astaxanthin attenuated LPS-induced oxidative stress, inflammation and cell apoptosis both in vivo and in vitro. In vivo and in vitro experiments showed that astaxanthin down regulated the nuclear factor-kappa beta (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2) and NLR family pyrin domain containing 3 (NLRP3) signalling pathways, inhibiting the LPS-induced inflammatory response, oxidative stress and cell apoptosis, and alleviating LPS-induced ALI in mice. [ABSTRACT FROM AUTHOR]

Dental caries can lead to inflammation or necrosis of the pulp, necessitating root canal treatment. However, this treatment carries the risk of pain, with its incidence influenced by the condition and quality of the pulp tissue. Immunologic and microbiologic factors play significant roles in determining the quality of the pulp tissue, thereby impacting the diagnosis of pulp tissue health. To elucidate the reduction in cell count resulting from the intrinsic apoptosis pathway of dental pulp nerve cells subsequent to lipopolysaccharide (LPS) administration, based on the expression levels of nitrotyrosine and F2-isoprostane. Thirty-two Sprague Dawley rats were divided into two groups. In the control group, only access opening was performed on the mandibular incisors of the rats. Conversely, in the treatment group, access opening was performed, and lipopolysaccharide (LPS) from Porphyromonas gingivalis was induced, left for 48 hours to induce an inflammatory condition, and subsequently terminated. Immunohistochemical staining was then employed to assess the expression of nitrotyrosine and F2-isoprostane. Additionally, the number of dental pulp nerve cells was observed using hematoxylin and eosin (HE) staining. Significant differences were observed in the expression levels of nitrotyrosine and F2- isoprostane, as well as in the number of nerve cells, between the control and treatment groups. Administration of lipopolysaccharide (LPS) leads to increased expression of nitrotyrosine and F2- isoprostane, while concurrently decreasing the number of dental pulp nerve cells affected by inflammation. [ABSTRACT FROM AUTHOR]

The early inflammatory phase, which is impacted by both local and systemic reactions to noxious stimuli, is crucial for bone regeneration. One component of Garcinia mangostana, called αmangostin, offers several advantages, including acting as an anti-inflammatory. With the production of related transcription factor-2 (RUNX2), which in turn causes the appearance of various osteogenesis markers, the WNT signaling pathway is a mechanism for the formation of osteogenesis through inflammation. To analyze the effect of α-mangostin on the LPS-induced inflammatory process on osteocalcin and interleukin-17A gene expression in osteoblast cell line culture. This study examines the expression of the genes for IL-17A and OCN in osteoblast cell culture using a post-test-only control group design. A total of 4 groups of cell cultures were created: group K with osteogenic medium, group P1 with osteogenic medium and lipopolysaccharide, group P2 with osteogenic medium and α-mangostin, and group P3 with osteogenic medium and a combination of lipopolysaccharide and α-mangostin. Using the same concentration for all concentrates, the therapy was administered over three days in osteogenic media. The sample will subsequently be prepared and subjected to RT-PCR analysis. Result is significant upregulation of IL-17A and OCN gene expression was observed in the group combination of lipopolysaccharide and α-mangostin. In conclusion α-mangostin can boost osteocalcin gene expression in osteoblast cell line culture after LPS induction, however, it was unable to diminish IL-17A gene expression in osteoblast cell line culture. [ABSTRACT FROM AUTHOR]

Acting through a combination of direct and indirect pathogen clearance mechanisms, blood-derived antimicrobial compounds (AMCs) play a pivotal role in innate immunity, safeguarding the host against invading microorganisms. Besides their antimicrobial activity, some AMCs can neutralize endotoxins, preventing their interaction with immune cells and avoiding an excessive inflammatory response. In this study, we aimed to investigate the influence of unfractionated heparin, a polyanionic drug clinically used as anticoagulant, on the endotoxin-neutralizing and antibacterial activity of blood-derived AMCs. Serum samples from healthy donors were pre-incubated with increasing concentrations of heparin for different time periods and tested against pathogenic bacteria (Acinetobacter baumannii, Enterococcus faecium, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus) and endotoxins from E. coli, K. pneumoniae, and P. aeruginosa. Heparin dose-dependently decreased the activity of bloodderived AMCs. Consequently, pre-incubation with heparin led to increased activity of LPS and higher values of the pro-inflammatory cytokines tumor necrosis factor a (TNF-a) and interleukin 6 (IL-6). Accordingly, higher concentrations of A. baumannii, E. coli, K. pneumoniae, and P. aeruginosa were observed as well. These findings underscore the neutralizing effect of unfractionated heparin on blood-derived AMCs in vitro and may lead to alternative affinity techniques for isolating and characterizing novel AMCs with the potential for clinical translation. [ABSTRACT FROM AUTHOR]

Atherosclerosis constitutes a proverbial pathogenic mechanism for cardio-cerebrovascular disease that accounts for the most common cause of disability and morbidity for human health worldwide. Endothelial dysfunction and inflammation are the key contributors to the progression of atherosclerosis. Glutaredoxin 2 (GLRX2) is abundantly existed in various tissues and possesses a range of pleiotropic efficacy including anti-oxidative and anti-inflammatory responses. However, its role in atherosclerosis is still undefined. Here, down-regulation of GLRX2 was validated in lipopolysaccha (LPS)-induced vascular endothelial cells (HUVECs). Moreover, elevation of GLRX2 reversed the inhibition of cell viability in LPS-treated HUVECs and decreased LPS-induced increases in cell apoptosis and caspase-3 activity. Additionally, enhancement of GLRX2 expression antagonized oxidative stress in HUVECs under LPS exposure by inhibiting ROS, lactate dehydrogenase and malondialdehyde production and increased activity of anti-oxidative stress superoxide dismutase. Notably, GLRX2 abrogated LPS-evoked transcripts and releases of pro-inflammatory cytokine (TNF-α, IL-6, and IL-1β), chemokine MCP-1 and adhesion molecule ICAM-1 expression. Furthermore, the activation of Nrf2/HO-1 signaling was demonstrated in LPS-stimulated HUVECs. Importantly, blockage of the Nrf2 pathway counteracted the protective roles of GLRX2 in LPS-triggered endothelial cell injury, oxidative stress and inflammatory response. Thus, these data reveal that GLRX2 may alleviate the progression of atherosclerosis by regulating vascular endothelial dysfunction and inflammation via the activation of the Nrf2 signaling, supporting a promising therapeutic approach for atherosclerosis and its complications. [ABSTRACT FROM AUTHOR]

Introduction: Saccharomyces cerevisiae is one of the most common probiotics used in ruminant nutrition. Saccharomyces cerevisiae increase gas production through specific biochemical mechanisms. Some of these mechanisms, based on the yeast's ability to excrete excess oxygen from the rumen, create a better space for ruminal anaerobic bacteria. The yeast Saccharomyces cerevisiae can provide a place for metabolic exchange and a suitable environment for the growth and activity of beneficial microorganisms around the substrates. On the other hand, increased gas production by adding yeast may be due to increased propionate fatty acid production due to improved ruminal fermentation. Because carbon dioxide is produced by some rumen bacteria through the succinatepropionate pathway when propionate is produced. Because the fermentation of dietary carbohydrates into volatile fatty acids produces gases in the rumen that are mainly hydrogen, carbon dioxide, and methane, the addition of yeast not only has the potential to improve gas production, but can cause qualitative changes in the gases produced and reduce the negative impact on the environment. The addition of yeast in concentrated diets increased the population of fiber decomposing microorganisms compared to the control group without adding yeast (Callaway& Martin 1997; Dehghan-Banadaky et al. 2012). Yeast also directly stimulates ruminal fungi, which may improve fiber digestion. Gas production forms the basis of any substrate, mainly dependent on the availability of nutrients for ruminal microorganisms it is quite clear that the increase in gas production was due to the increase in crude protein content. It is well known that Saccharomyces cerevisiae can reduce the production of ammonia in the rumen. Ammonia emissions from cattle manure reduces by reducing protein degradation and overall nitrogen excretion by the animal. The direct result of this action is an increase in protein bypass in the rumen, which is absorbed and metabolized as a real protein in the gastrointestinal tract and small intestine. Reducing the latency phase by increasing the protein content (for example, a diet with higher crude protein) indicates the rapid activity of Saccharomyces cerevisiae on the fermentation process. In addition, Saccharomyces cerevisiae contains small peptides and other nutrients that are needed by the dominant ruminal cellulite bacteria to initiate growth. The activity of Saccharomyces cerevisiae depends on many factors, including the availability of nutrients to rumen microorganisms, which stimulates the fermentation process (Newbold et al. 1995). This study aimed to investigate the effects of yeast supplementation on fermentation parameters in total mixed rations in vitro. Materials and methods: Accordingly, the effect of 4 levels of yeast supplementation involved, zero, 4, 8, and 12 mg/g of yeast in two TMR diets containing 60 and 70% of concentrates, on the kinetics and parameters of gas production, rumen fermentation parameters including pH, ammonia nitrogen, concentration and profiles of volatile fatty acids, and true digestibility of dry matter and neutral detergent fibers were evaluated. In addition, the effect of yeast supplementation on the population of protozoa, anaerobic fungi, and cellulolytic microorganisms were evaluated using molecular techniques. In this experiment, three adult Holstein steers equipped with ruminal fistulas were used to prepare ruminal fluid. For the polymerase chain reaction, after sequencing of the primers, the extracted DNA was amplified using PCR to check primer specificity. DNA amplification was examined by the system (R-T PCR) with three replications for each pair of primers. Results and discussion: The addition of different levels of Saccharomyces cerevisiae supplementation caused a significant increase (P<0.05) in the amount of gas produced by increasing the incubation time of experimental diets. The results show that there is a statistically significant difference (P<0.05) between different levels of supplementation; so that from 24 hours after incubation onwards, the highest amount of gas produced in the experimental diets was at the level of 12 mg/g supplement was observed. The addition of different levels of Saccharomyces cerevisiae supplementation caused a significant increase (P<0.05) in the total amount of VFA produced in the rumen with increasing levels of supplementation in experimental diets. The results show that there is a statistically significant difference (P<0.05) between different levels of supplementation so that the highest amount of total VFA produced in both diets was observed at the level of 12 mg/g supplement. The effect of adding different levels of Saccharomyces cerevisiae supplementation on ruminal parameters caused a significant increase (P<0.05) in ruminal pH and a decrease in ruminal ammonia production by increasing the level of supplementation in experimental diets. The results show that there is a statistically significant difference between different levels of supplementation so that the greatest increase in ruminal pH and decrease in ammonia production in experimental diets at the level of 12 mg/g. The effect of diet type was also significantly different (P<0.05). The highest increase in ruminal pH and decrease in ammonia production was observed in diets containing 60% concentrate. The results of this study showed that the yeast supplementation in high fermentative TMR diets increased (P<0.05) the rumen environmental stability, increased (P<0.05) the fermentability of dietary insoluble fraction, reduced (P<0.05) the gas production rate and reduced (P<0.05) the lag phase. addition of Saccharomyces cerevisiae in higher crude protein diets, improved of the dry matter digestibility. Nutrient analysis without affecting the digestibility of insoluble fibers in neutral detergent and the digestibility of soluble fibers in acidic detergent with diets containing higher crude vitamin, even with the addition of Saccharomyces cervicia, improved dry matter digestibility and organic matter digestibility. However, Saccharomyces cerevisiae only affects the edibility of the desiccant. Both diets had different crude production. Therefore, improving the treatability of dry matter and the edibility of organic matter was the result of increasing the raw material, which improved micro activities in the rumen. Conclusions: Yeast supplementation improved fiber digestibility and reduced lactate accumulation and LPS concentration by stabilizing the anaerobic environment in the rumen and stimulating the growth and activity of fiber-degrading microorganisms. [ABSTRACT FROM AUTHOR]

Artemisia argyi H.Lév. & Vaniot essential oil (AAEO) has shown pharmacological effects such as anti‐inflammation, antioxidant, and anti‐tumor properties. However, the protective effect of AAEO on lipopolysaccharide (LPS)‐induced liver injury and its potential protective mechanism are still unclear. In this study, we used ultra‐performance liquid chromatography tandem mass spectrometry metabolomics techniques to investigate the changes in liver tissue metabolites in mice exposed to LPS with or without AAEO treatment for 14 days. The biochemical results showed that compared with the control group, AAEO significantly reduced the levels of liver functional enzymes, suggesting a significant improvement in liver injury. In addition, the 18 differential metabolites identified by metabolomics were mainly involved in the reprogramming of arachidonic acid metabolism, tryptophan metabolism, and purine metabolism. AAEO could significantly inhibit the expression of COX‐2, IDO1, and NF‐κB; enhance the body's anti‐inflammatory ability; and alleviate liver injury. In summary, our study identified the protective mechanism of AAEO on LPS‐induced liver injury at the level of small molecular metabolites, providing a potential liver protective agent for the treatment of LPS‐induced liver injury. [ABSTRACT FROM AUTHOR]

Apolipoprotein E4 (ApoE4) is involved in the stress‐response processes and is hypothesized to be a risk factor for depression by means of mitochondrial dysfunction. However, their exact roles and underlying mechanisms are largely unknown. ApoE4 transgenic mice (B6. Cg‐ApoEtm1UncCdh18Tg(GFAP−APOE i4)1Hol/J) were subjected to stress (lipopolysaccharides, LPS) to elucidate the aetiology of ApoE4‐induced depression. LPS treatment significantly aggravated depression‐like behaviours, concurrent with neuroinflammation and impaired mitochondrial changes, and melatonin/Urolithin A (UA) + 5‐aminoimidazole‐4‐carboxamide 1‐β‐D‐ribofuranoside (AICAR) reversed these effects in ApoE4 mice. Concurrently, ApoE4 mice exhibited mitophagy deficits, which could be further exacerbated by LPS stimulation, as demonstrated by reduced Atg5, Beclin‐1 and Parkin levels, while PINK1 levels were increased. However, these changes were reversed by melatonin treatment. Additionally, proteomic profiling suggested mitochondria‐related signalling and network changes in ApoE4 mice, which may underlie the exaggerated response to LPS. Furthermore, HEK 293T cells transfected with ApoE4 showed mitochondria‐associated protein and mitophagy defects, including PGC‐1α, TFAM, p‐AMPKα, PINK1 and LC3B impairments. Additionally, it aggravates mitochondrial impairment (particularly mitophagy), which can be attenuated by triggering autophagy. Collectively, ApoE4 dysregulation enhanced depressive behaviour upon LPS stimulation. [ABSTRACT FROM AUTHOR]

IntroductionIntestinal dysfunction poses a severe problem by preventing the digestion and absorption of nutrients. The gut, being the most vital organ for these processes, plays a crucial role in ensuring our body receives the nutrients it needs. We explored the mitigating effect of Morchella esculenta polysaccharides (MEP) on intestinal injury induced by lipopolysaccharides (LPS) through the modulation of intestinal flora.MethodsFor this purpose, Kunming mice (KM) were divided into three groups, namely, PC, PM, and PY. Group PY was treated with MEP, while groups PM and PY were induced with LPS.ResultsThe results showed that weight loss in the PM group was significantly greater than that in the PY group (P < 0.05), and the organ indexes of the lung and spleen in the PM group were significantly higher than those in the PC (P < 0.01) and PY (P < 0.05) groups. LPS caused severe injuries in KM mice in the PM group, characterized by broken villi. However, MEP treatment could alleviate this damage in the PY group, resulting in relatively intact villi. The serum analysis showed that tumor necrosis factor alpha (TNF-ɑ) (P < 0.01), interleukin 6 (IL-6) (P < 0.01), and 3,4-methylenedioxyamphetamine (MDA) (P < 0.05) levels were significantly higher in the PM group, while IL-10 (P < 0.001), superoxide dismutase (SOD) (P < 0.01) and glutathione peroxidase (GSH-Px) (P < 0.01) were significantly lower in that group. Interestingly, supplementation with MEP could lower the levels of TNF-ɑ, IL-10, IL-6, MDA while increasing the levels of superoxide dismutase (SOD) (P < 0.01) and GSH-Px. The gut microbiota analysis yielded 630,323 raw reads and 554,062 clean reads, identifying 3,390 amplicon sequencing variants (ASVs). One phylum and five genera were notably different among animal groups, including Escherichia_Shigella, Limosilactobacillus, unclassified_Geminicoccaceae, unclassified_Rhodobacteraceae, and Parabacteroides (P. distasonis).DiscussionIn conclusion, we found that MEP could mitigate the intestinal damage caused by LPS by modulating the inflammatory response, oxidative resistance, and intestinal flora of KM mice. Our results may provide insights into novel treatment options for intestine-related diseases.

The etiology of Hashimoto's thyroiditis is still unclear. Genetic predisposition and the effects of various environmental factors are discussed. The present article is a systematic review of publications on the occurrence and development of this disease in the presence of impaired functions of the gastrointestinal tract and changes in the microbiota. Increased intestinal permeability, as well as changes in the microbiota, can disrupt the normal functioning of the immune system and can lead to the development of an autoimmune disease. Normalization of the diversity of the microbiota before an autoimmune process occurs can be achieved both with the use of pro-biotic strains and with appropriate dietary changes.

Objective: During infection, metabolism and immunity react dynamically to promote survival through mechanisms that remain unclear. Pro-opiomelanocortin (POMC) cleavage products are produced and released in the brain and in the pituitary gland. One POMC cleavage product, alpha-melanocyte-stimulating hormone (α-MSH), is known to regulate food intake and energy expenditure and has anti-inflammatory effects. However, it is not known whether α-MSH is required to regulate physiological anti-inflammatory responses. We recently developed a novel mouse model with a targeted mutation in Pomc (Pomctm1/tm1 mice) to block production of all α-MSH forms which are required to regulate metabolism. To test whether endogenous α-MSH is required to regulate immune responses, we compared acute bacterial lipopolysaccharide (LPS)-induced inflammation between Pomctm1/tm1 and wild-type Pomcwt/wt mice. Methods: We challenged 10- to 14-week-old male Pomctm1/tm1 and Pomcwt/wt mice with single i.p. injections of either saline or low-dose LPS (100 μg/kg) and monitored immune and metabolic responses. We used telemetry to measure core body temperature (Tb), ELISA to measure circulating cytokines, corticosterone and α-MSH, and metabolic chambers to measure body weight, food intake, activity, and respiration. We also developed a mass spectrometry method to measure three forms of α-MSH produced in the mouse hypothalamus and pituitary gland. Results: LPS induced an exaggerated immune response in Pomctm1/tm1 compared to Pomcwt/wt mice. Both groups of mice were hypoactive and hypothermic following LPS administration, but Pomctm1/tm1 mice were significantly more hypothermic compared to control mice injected with LPS. Pomctm1/tm1 mice also had reduced oxygen consumption and impaired metabolic responses to LPS compared to controls. Pomctm1/tm1 mice had increased levels of key proinflammatory cytokines at 2 h and 4 h post LPS injection compared to Pomcwt/wt mice. Lastly, Pomcwt/wt mice injected with LPS compared to saline had increased total α-MSH in circulation 2 h post injection. Conclusions: Our data indicate endogenous α-MSH contributes to the inflammatory immune responses triggered by low-dose LPS administration and suggest that targeting the melanocortin system could be a potential therapeutic for the treatment of sepsis or inflammatory disease.

ABSTRACT Methionine (Met) and cysteine (Cys) are nutrients in broiler diets, responsible for strengthening protein synthesis, immunity, and metabolic regulation. To estimate the ideal digestible Met + Cys:digestible Lysine (Lys) ratio for broilers under a lipopolysaccharide (LPS) inflammatory challenge, 384 male broilers were distributed in a completely randomized 4×2 factorial design, with four ratios of dig. Met + Cys:dig. Lys (0.69, 0.73, 0.77, and 0.81) and two conditions (with or without challenge). Each treatment had eight replicates, with six birds per experimental unit (EU). The evaluated parameters included broilers’ weight gain (WG), feed intake (FI), and feed conversion ratio (FCR); jejunum mRNA transcript levels of nuclear factor kappa-B (NF-Κb), glutathione peroxidase (GPX), superoxide dismutase (SOD), glutathione synthetase (GSS), and methionine adenosyltransferase 2 (MAT2); relative weights of liver and spleen, and fat mass (%) and lean mass (%). A linear regression model would estimate the ideal ratio if an effect had occurred. No interaction (p>0.05) was observed between the factors for all the data, nor did the different ratios had any effect (p>0.05) either. LPS-administered exhibited reduced performance, heavier liver and spleen, and lower GSS expression. Hence, the lowest dig Met + Cys:dig Lys ratio (0.69) was sufficient to maintain the performance parameters, the relative weight of lymphoid organs, fat and lean mass, and NF-Kb, GPX, SOD, GSS, MAT2, and CBS mRNA transcript levels in the jejunum.

Intense neuroinflammation contributes to neurodegenerative diseases, such as Alzheimer’s disease and Parkinson’s disease. Lipopolysaccharides (LPSs) are an integral part of the cell wall of Gram-negative bacteria that act as pathogen-associated molecular patterns (PAMPs) and potentially activate the central nervous system’s (CNS) immune system. Microglial cells are the local macrophages of the CNS and have the potential to induce and control neuroinflammation. This study aims to evaluate the anti-inflammatory and antioxidant effect of kojic acid against the toxic effects of LPSs, such as neuroinflammation-induced neurodegeneration and cognitive decline. The C57BL/6N mice were subjected to LPS injection for 2 weeks on alternate days (each mouse received 0.25 mg/kg/i.p. for a total of seven doses), and kojic acid was administered orally for 3 weeks consecutively (50 mg/kg/mouse, p. o). Bacterial endotoxins, or LPSs, are directly attached to TLR4 surface receptors of microglia and astrocytes and alter the cellular metabolism of immune cells. Intraperitoneal injection of LPS triggers the toll-like receptor 4 (TLR4), phospho-nuclear factor kappa B (p-NFκB), and phospho-c-Jun n-terminal kinase (p-JNK) protein expressions in the LPS-treated group, but these expression levels were significantly downregulated in the LPS + KA-treated mice brains. Prolong neuroinflammation leads to the generation of reactive oxygen species (ROS) followed by a decrease in nuclear factor erythroid-2-related factor 2 (Nrf2) and the enzyme hemeoxygenase 1 (HO-1) expression in LPS-subjected mouse brains. Interestingly, the levels of both Nrf-2 and HO-1 increased in the LPS + KA-treated mice group. In addition, kojic acid inhibited LPS-induced TNF-α and IL-1β production in mouse brains. These results indicated that kojic acid may suppress LPS-induced neuroinflammation and oxidative stress in male wild-type mice brains (in both the cortex and the hippocampus) by regulating the TLR4/NF-κB signaling pathway.

In this study, the pathogenic genes of depression were calculated and analyzed by bioinformatics method, and then the key genes of Shaoyao Gancao Decoction in the treatment of depression were deduced and predicted through the correlation study with the target of Shaoyao Gancao Decoction. Through the production of LPS depression model mice, drug treatment, behavioral test and hippocampal tissue sample detection, it was found that Shaoyao Gancao Decoction can regulate the levels of IL-10, TNF- α, BDNF, SMAD3, FGFR1 and FGFR2 to improve depression, which can provide a theoretical basis for exploring the efficacy of Shaoyao Gancao Decoction in the treatment of depression.

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 (Mφs). 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 Mφ inflammatory responses in various bacterial infection models.

BackgroundThere is a link between cardiovascular diseases and intestinal permeability, but it is not clear. This review aimed to elucidate intestinal permeability in cardiovascular diseases by meta-analysis.MethodsMultidisciplinary electronic databases were searched from the database creation to April 2023. All included studies were assessed for risk of bias according to the Joanna Briggs Institute Critical Appraisal Checklist. The heterogeneity of each study was estimated using the I2 statistic, and the data were analyzed using Review Manager 5.3 and Stata 16.0.ResultsIn total, studies in 13 pieces of literature were included in the quantitative meta-analysis. These studies were conducted among 1,321 subjects mostly older than 48. Patients had higher levels of intestinal permeability markers (lipopolysaccharide, d-lactate, zonulin, serum diamine oxidase, lipopolysaccharide-binding protein, intestinal fatty acid binding protein, and melibiose/rhamnose) than controls (standard mean difference SMD = 1.50; 95% CI = 1.31–1.88; p

IntroductionLipopolysaccharides (LPS) present in the intestine are suggested to enter the bloodstream after consumption of high-fat diets and cause systemic inflammation and metabolic dysregulation through a process named “metabolic endotoxemia.” This study aimed to determine the role of orally administered LPS to mice in the early stage of chronic low-grade inflammation induced by diet.MethodsWe supplemented the drinking water with E. coli derived LPS to mice fed either high-fat Western-style diet (WSD) or standard chow (SC) for 7 weeks (n = 16–17). Body weight was recorded weekly. Systemic inflammatory status was assessed by in vivo imaging of NF-κB activity at different time points, and glucose dysregulation was assessed by insulin sensitivity test and glucose tolerance test near the end of the study. Systemic LPS exposure was estimated indirectly via quantification of LPS-binding protein (LBP) and antibodies against LPS in plasma, and directly using an LPS-sensitive cell reporter assay.Results and discussionOur results demonstrate that weight development and glucose regulation are not affected by LPS. We observed a transient LPS dependent upregulation of NF-κB activity in the liver region in both diet groups, a response that disappeared within the first week of LPS administration and remained low during the rest of the study. However, WSD fed mice had overall a higher NF-κB activity compared to SC fed mice at all time points independent of LPS administration. Our findings indicate that orally administered LPS has limited to no impact on systemic inflammation and metabolic dysregulation in mice fed a high-fat western diet and we question the capability of intestinally derived LPS to initiate systemic inflammation through a healthy and uncompromised intestine, even when exposed to a high-fat diet.

With the rapid development of immunotherapy in recent years, cytokine storm has been recognized as a common adverse effect of immunotherapy. The emergence of COVID-19 has renewed global attention to it. The cytokine storm's inflammatory response results in infiltration of large amounts of monocytes/macrophages in the lungs, heart, spleen, lymph nodes, and kidneys. This infiltration leads to secondary tissue damage, acute respiratory distress syndrome (ARDS), organismal damage, and even death. However, there is currently no designated treatment for cytokine storm and the resulting ARDS. Consequently, there is a pressing need to identify a pharmaceutical agent that can effectively mitigate cytokine storms. Ebosin is a new exopolysaccharide generated by Streptomyces sp.139 and pharmacological activity for cytokine storm is investigated in vivo. The results show that Ebosin significantly augments the survival rates of mice, and its effectiveness increases with higher doses. It significantly inhibited the expression of cytokines IL-5, IL-6, IL-9 and chemokine Eotaxin in serum and lung tissues. Ebosin can alleviate the pathological damage in the lungs, liver, and spleen caused by LPS. Additionally, it can inhibit the phosphorylation of IKKα/β, Stat3 and NF-κB p65 upon LPS stimulation in vitro. We hypothesized that Ebosin may decrease cytokine release by inhibiting the phosphorylation of IKKα/β, Stat3, and NF-κB p65, neutrophil infiltration in animals. The article preliminarily elucidated the activity and mechanism of Ebosin against cytokine storm, which provides a reference for the study of anti-cytokine storm activity of microbial natural products.

Polycystic ovary syndrome (PCOS) is associated with an increased risk of psychological distress as well as enhanced responses to psychosocial stress. Recently, it was hypothesized that PCOS patients may be at high risk of novel COVID-19 infections and worse clinical presentations during such infections. Here, we evaluated the effects of PCOS on stress responses to bacterial and viral mimetics using dihydrotestosterone-induced PCOS model rats. Lipopolysaccharide (LPS; a bacterial mimetic) or polyinosinic-polycytidylic acid (Poly-IC; a viral mimetic) was injected into PCOS model rats (PCOS) and non-PCOS rats (control), and the rats' stress responses were evaluated. In the PCOS group, the rats’ anorectic and febrile responses to LPS injection were enhanced, whereas their anorectic and febrile responses to Poly-IC injection were unaltered. The PCOS group also exhibited greater changes in peripheral cytokine levels in response to LPS, but not Poly-IC. On the contrary, after the injection of Poly-IC depressed locomotor activity was more evident in the PCOS group, whereas no such changes were observed after LPS injection. These findings indicate that although the stress responses of PCOS model rats to infection may be enhanced, the patterns of change in stress responses and their underlying mechanisms may differ between bacterial and viral infections.

Pyroptosis induced by lipopolysaccharide (LPS) has an obvious impact on intestinal inflammation and immune regulation. Enterotoxigenic Escherichia coli (ETEC) K88 has been proved to induce inflammatory responses in several models, but whether E. coli K88 participates in the same process of pyroptotic cell death as LPS remains to be identified. We conducted a pilot experiment to confirm that E. coli K88, instead of Escherichia coli O157 and Salmonella typhimurium, promotes the secretion of interleukin-1 beta (IL-1β) and interleukin-18 (IL-18) in macrophages. Further experiments were carried out to dissect the molecular mechanism both in vitro and in vivo. The Enzyme-Linked Immunosorbent Assay (ELISA) results suggested that E. coli K88 treatment increased the expression of pro-inflammatory cytokines IL-18 and IL-1β in both C57BL/6 mice and the supernatant of J774A.1 cells. Intestinal morphology observations revealed that E. coli K88 treatment mainly induced inflammation in the colon. Real-time PCR and Western blot analysis showed that the mRNA and protein expressions of pyroptosis-related factors, such as NLRP3, ASC, and Caspase1, were significantly upregulated by E. coli K88 treatment. The RNA-seq results confirmed that the effect was associated with the activation of NLRP3, ASC, Caspase1, GSDMD, IL-18, and IL-1β, and might also be related to inflammatory bowel disease and the tumor necrosis factor pathway. The pyroptosis-activated effect of E. coli K88 was significantly blocked by NLRP3 siRNA. Our data suggested that E. coli K88 caused inflammation by triggering pyroptosis, which provides a theoretical basis for the prevention and treatment of ETEC in intestinal infection.

Background & Aims: Nonalcoholic fatty liver disease is the most prevalent chronic liver disease and threats to human health. Gut dysbiosis caused by lipopolysaccharide (LPS) leakage has been strongly related to nonalcoholic fatty liver disease progression, although the underlying mechanisms remain unclear. Methods: Previous studies have shown that low-grade LPS administration to mice on a standard, low-fat chow diet is sufficient to induce symptoms of fatty liver. This study confirmed these findings and supported LPS as a lipid metabolism regulator in the liver. Results: Mechanically, LPS induced dysregulated lipid metabolism by inhibiting the expression of DNA methyltransferases 3B (DNMT3B). Genetic overexpression of DNMT3B alleviated LPS-induced lipid accumulation, whereas its knockdown increased steatosis in mice and human hepatocytes. LPS-induced lower expression of DNMT3B led to hypomethylation in promoter region of CIDEA, resulting in increased binding of SREBP-1c to its promoter and activated CIDEA expression. Hepatic interference of CIDEA reversed the effect of LPS on lipogenesis. These effects were independent of a high-fat diet or high fatty acid action. Conclusions: Overall, these findings sustain the conclusion that LPS is a lipogenic factor and could be involved in hepatic steatosis progression.

Abstract Sepsis is a life-threatening state that arises due to a hyperactive inflammatory response stimulated by infection and rarely other insults (e.g., non-infections tissue injury). Although changes in several proinflammatory cytokines and signals are documented in humans and small animal models, far less is known about responses within affected tissues of large animal models. We sought to understand the changes that occur during the initial stages of inflammation by administering intravenous lipopolysaccharide (LPS) to Yorkshire pigs and assessing transcriptomic alterations in the brain, kidney, and whole blood. Robust transcriptional alterations were found in the brain, with upregulated responses enriched in inflammatory pathways and downregulated responses enriched in tight junction and blood vessel functions. Comparison of the inflammatory response in the pig brain to a similar mouse model demonstrated some overlapping changes but also numerous differences, including oppositely dysregulated genes between species. Substantial changes also occurred in the kidneys following LPS with several enriched upregulated pathways (cytokines, lipids, unfolded protein response, etc.) and downregulated gene sets (tube morphogenesis, glomerulus development, GTPase signal transduction, etc.). We also found significant dysregulation of genes in whole blood that fell into several gene ontology categories (cytokines, cell cycle, neutrophil degranulation, etc.). We observed a strong correlation between the brain and kidney responses, with significantly shared upregulated pathways (cytokine signaling, cell death, VEGFA pathways) and downregulated pathways (vasculature and RAC1 GTPases). In summary, we have identified a core set of shared genes and pathways in a pig model of systemic inflammation.

Objective: To investigate the underlying mechanism of anti-inflammatory action of coumarin and eugenol in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Methods: RAW 264.7 cells were treated with 2.5 μg/mL of LPS, 50 μM of coumarin, and 50 μM eugenol for 24 h. The viability of the cells was assessed using MTT assay. The production of nitric oxide was determined using Griess reagent and DCFH-DA was used to measure the production of reactive oxygen species. The protein expression of NLRP3, IL-1β, NF-κB, and cyclooxygenase 2 was assessed using Western blot analysis. Results: Coumarin and eugenol showed anti-inflammatory effects against LPS-induced inflammatory response by ameliorating the expression of NLRP3 inflammasome and NF-κB, which further led to a subsequent reduction in IL-1β, nitric oxide, and reactive oxygen species. Conclusions: Coumarin and eugenol exert their anti-inflammatory activities by modulating the NLRP3 inflammasome pathway and NF-κB. These compounds may have promising therapeutic applications for the treatment of various inflammatory diseases.

Abstract Background Sepsis-induced acute lung injury (ALI) accounts for about 40% of ALI, accompanied by alveolar epithelial injury. The study aimed to reveal the role of circular RNA_0114428 (circ_0114428) in sepsis-induced ALI. Methods Human pulmonary alveolar epithelial cells (HPAEpiCs) were treated with lipopolysaccharide (LPS) to mimic a sepsis-induced ALI cell model. RNA expression of circ_0114428, miR-574-5p and Rho-associated coiled-coil containing protein kinase 2 (ROCK2) was detected by qRT-PCR. Protein expression was checked by Western blotting. Cell viability, proliferation and apoptosis were investigated by cell counting kit-8, 5-Ethynyl-29-deoxyuridine (EdU) and flow cytometry analysis, respectively. The levels of pro-inflammatory factors were detected by enzyme-linked immunosorbent assay (ELISA). Oxidative stress was analyzed by lipid peroxidation Malondialdehyde (MDA) and Superoxide Dismutase (SOD) activity detection assays. The interplay among circ_0114428, miR-574-5p and ROCK2 was identified by dual-luciferase reporter, RNA pull-down and RNA immunoprecipitation assays. Results Circ_0114428 and ROCK2 expression were significantly increased, but miR-574-5p was decreased in blood samples from sepsis patients and LPS-stimulated HPAEpiCs. LPS treatment led to decreased cell viability and proliferation and increased cell apoptosis, inflammation and oxidative stress; however, these effects were relieved after circ_0114428 knockdown. Besides, circ_0114428 acted as a miR-574-5p sponge and regulated LPS-treated HPAEpiC disorders through miR-574-5p. Meanwhile, ROCK2 was identified as a miR-574-5p target, and its silencing protected against LPS-induced cell injury. Importantly, circ_0114428 knockdown inhibited ROCK2 production by interacting with miR-574-5p. Conclusion Circ_0114428 knockdown protected against LPS-induced HPAEpiC injury through miR-574-5p/ROCK2 axis, providing a novel therapeutic target in sepsis-induced ALI.

Abstract Background The benefits of combining benzoic acid and essential oils (BAO) to mitigate intestinal impairment during the weaning process have been well established, while the detailed underlying mechanism has not been fully elucidated. Previous research has primarily focused on the reparative effects of BAO on intestinal injury, while neglecting its potential in enhancing intestinal stress resistance. Methods In this study, we investigated the pre-protective effect of BAO against LPS-induced stress using a modified experimental procedure. Piglets were pre-supplemented with BAO for 14 d, followed by a challenge with LPS or saline to collect blood and intestinal samples. Results Our findings demonstrated that BAO supplementation led to significant improvements in piglets' final weight, average daily gain, and feed intake/body gain ratio. Additionally, BAO supplementation positively influenced the composition of intestinal microbiota, increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota, Prevotella and Oscillospira. Furthermore, BAO supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS challenge. This was evidenced by elevated levels of T-AOC, SOD, and GSH, as well as decreased levels of MDA, TNF-α, and IL-6 in the plasma. Moreover, piglets subjected to LPS challenge and pre-supplemented with BAO exhibited significant improvements in intestinal morphological structure and enhanced integrity, as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented counterparts. Further analysis revealed that BAO supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling pathway. Additionally, the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with BAO. Conclusions In summary, our study demonstrates that pre-supplementation of BAO enhances the anti-stress capacity of weaned piglets by improving intestinal microbiota composition, reinforcing the intestinal barrier, and enhancing antioxidative and anti-inflammatory capabilities. These effects are closely associated with the activation of Nrf2 and TLR4/NF-κB/MAPK signaling pathways.

Abstract Background Emerging proofs have shown that differentially expressed circular RNAs (circRNAs) are closely associated with the pathophysiological process of spinal cord injury (SCI). Mesenchymal stem cell (MSC)-exosomes have been demonstrated to possess favorable therapeutic effects in diseases. Herein, this work aimed to investigate the action of circ_0006640 transferred by MSC-exosomes functional recovery after SCI. Methods SCI animal models were established by spinal cord contusion surgery in mice and lipopolysaccharide (LPS)-stimulated mouse microglial cell line BV2. Levels of genes and proteins were detected by qRT-PCR and Western blot. Properties of BV2 cells were characterized using CCK-8 assay, flow cytometry and ELISA analysis. The oxidative stress was evaluated. Dual-luciferase reporter assay was used for verifying the binding between miR-382-5p and circ_0006640 or IGF-1 (Insulin-like Growth Factor 1). Exosome separation was conducted by using the commercial kit. Results Circ_0006640 expression was lower in SCI mice and LPS-induced microglial cells. Circ_0006640 overexpression protected microglial cells from LPS-induced apoptotic, inflammatory and oxidative injury. Mechanistically, circ_0006640 directly sponged miR-382-5p, which targeted IGF-1. MiR-382-5p was increased, while IGF-1 was decreased in SCI mice and LPS-induced microglial cells. Knockdown of miR-382-5p suppressed apoptosis, inflammation and oxidative stress in LPS-induced microglial cells, which were reversed by IGF-1 deficiency. Moreover, miR-382-5p up-regulation abolished the protective functions of circ_0006640 in LPS-induced microglial cells. Additionally, circ_0006640 was packaged into MSC-exosomes and could be transferred by exosomes. Exosomal circ_0006640 also had protective effects on microglial cells via miR-382-5p/IGF-1 axis. Conclusion Circ_0006640 transferred by BMSC-exosomes suppressed LPS-induced apoptotic, inflammatory and oxidative injury via miR-382-5p/IGF-1 axis, indicating a new insight into the clinical application of exosomal circRNA-based therapeutic in the function recovery after SCI.

Bacteriophage (phage) AP1 has been reported to effectively lyse Acidovorax oryzae, the causative agent of bacterial brown stripe in rice. However, phage AP1 exhibits strain-specific lysis patterns. In order to enhance the potential of phages for biological control of rice bacterial brown stripe, this study investigated the possible mechanism of strain-specific infection by characterizing phage AP1 and its susceptible (RS-2) and resistant (RS-1) strains. Based on the current classification standards and available database information, phage AP1 was classified into the class Caudoviricetes, and it is a kind of podophage. Comparative analysis of the susceptible and resistant strains showed no significant differences in growth kinetics, motility, biofilm formation, or effector Hcp production. Interestingly, the resistant strain demonstrated enhanced virulence compared to the susceptible strain. Prokaryotic expression studies indicated that six putative structural proteins of phage AP1 exhibited varying degrees of binding affinity (1.90–9.15%) to lipopolysaccharide (LPS). However, pull-down assays and bacterial two-hybrid analyses revealed that only gp66 can interact with four host proteins, which were identified as glycosyltransferase, RcnB, ClpB, and ImpB through immunoprecipitation and mass spectrometry analyses. The role of LPS in the specific infection mechanism of phage AP1 was further elucidated through the construction of knockout mutant strains and complementary strains targeting a unique gene cluster (wbzB, wbzC, wbzE, and wbzF) involved in LPS precursor biosynthesis. These findings provide novel insights into the mechanisms of phage-host specificity, which are crucial for the effective application of phage AP1 in controlling rice bacterial brown stripe.

Identifying blood components influenced by rearing systems that serve as biomarkers to distinguish free-range from conventional broilers can improve animal health, welfare, and productivity. The current study aimed to evaluate specific blood parameters related to immune function and tissue stress, as biomarkers to differentiate free-range, slow-growing Sasso broilers from conventionally raised fast-growing Ross 308 broilers. For this purpose, serum IgM Natural Antibodies (NAbs) targeting actin and lipopolysaccharides (LPS) as key immunological parameters of natural immunity, along with creatine phosphokinase (CPK) and other significant stress and tissue-related biochemical parameters, were measured in a total of 300 broilers (150 per group) raised under industrial scale rearing systems, by standard methodology. Our results showed significantly higher IgM-NAb levels to both antigens and lower CPK and Aspartate Aminotransferase levels in Sasso broilers compared to Ross 308 broilers (p < 0.001). Combination of anti-LPS IgM-NAbs and CPK levels, as the most potent biomarker candidates, achieved 90% sensitivity and 84% specificity in distinguishing Ross 308 from Sasso broilers. In conclusion, the combined evaluation of these blood biomarkers can effectively discriminate conventional from free-range broilers analyzed herein, with potent novel applications in the poultry industry making it a promising, cost effective and easy-to-use, diagnostic tool.

A balanced inflammatory response is crucial for the organism to defend against external infections, however, an exaggerated response may lead to detrimental effects, including tissue damage and even the onset of disease. Therefore, anti-inflammatory drugs are essential for the rational control of inflammation. In this study, we found that a previously screened peptide TaY (KEKKEVVEYGPSSYGYG) was able to inhibit the LPS-induced RAW264.7 inflammatory response by decreasing a series of proinflammatory cytokines, such as TNF-α, IL-6, and nitric oxide (NO). To elucidate the underlying mechanism, we conducted further investigations. Western blot analysis showed that TaY reduced the phosphorylation of key proteins (IKK-α/β, IκB-α,NF-κB (P65)) in the TLR4-NF-κB signaling pathway and inhibited the inflammatory response. Furthermore, molecular docking and molecular dynamic simulations suggested that TaY binds to the hydrophobic pocket of MD2 through hydrogen bonding and hydrophobic interactions, potentially competing with LPS for MD2 binding. Collectively, TaY is a promising candidate for the development of novel therapeutic strategies against inflammatory disorders.

Endometritis represents a prevalent condition in perinatal dairy cows. Bovine endometrial epithelial cells (BEECs), as the primary interface between cavity and the external environment, are particularly vulnerable to infection by pathogenic bacteria following parturition. A20 is essential for regulating inflammation and modulating immune responses. Nevertheless, the exact role of A20 in the BEECs in response to inflammatory response is not fully understood. An endometritis model infected by Escherichia coli (E. coli) in vivo and a BEECs inflammation model induced with lipopolysaccharide (LPS) in vitro were built to investigate the function and governing mechanisms of A20 in endometritis. The results showed that infection with E. coli resulted in endometrial damage, inflammatory cell infiltration, and upregulation of inflammatory factors in dairy cows. Furthermore, A20 expression was upregulated in the endometrium of cows with endometritis and in BEECs following LPS stimulation. A20 overexpression attenuated the level of proinflammatory cytokines in LPS-stimulated BEECs; conversely, A20 knockdown lead to an exacerbated response to LPS stimulation. The overexpression of A20 was shown to activate autophagy and suppress the NF-κB signaling pathway in LPS-stimulated BEECs. However, blocking autophagy with chloroquine notably attenuated the anti-inflammatory effect of A20, leading to the activation of the NF-κB signaling pathway. In summary, the study demonstrated that A20’s suppression of inflammation in LPS-stimulated BEECs is associated with the activation of autophagy. Therefore, the A20 protein showed potential as a novel treatment focus for managing endometritis in dairy cows.

The salmonid industry faces challenges due to the susceptibility of fish to opportunistic pathogens, particularly in early developmental stages. Understanding the immunological capacity during these stages is crucial for developing effective disease control strategies. IL-8R, a member of the G-protein-coupled receptor family, acts as a receptor for Interleukin 8 (IL-8). The binding of IL-8 to IL-8R plays a major role in the pathophysiology of a wide spectrum of inflammatory conditions. This study focused on the immune response capacity of rainbow trout (Oncorhynchus mykiss) larvae by analyzing IL-8/CXCR1 response to lipopolysaccharide (LPS) from Pseudomonas aeruginosa. Previous research demonstrated that LPS from P. aeruginosa acts as a potent immunostimulant in teleost, enhancing pro-inflammatory cytokines. The methodology included in silico analysis and the synthesis and characterization of an omCXCR1-derived epitope peptide, which was used to produce omCXCR1-specific anti98 serum in mice. The research revealed that rainbow trout larvae 19 days post-hatching (dph) exhibited pronounced immune responses post-stimulation with 1 µg/mL of LPS. This was evidenced by the upregulated protein expression of IL-8 and omCXCR1 in trout larvae 2 and 8 h after LPS challenge, as analyzed by ELISA and immunohistochemistry. Furthermore, fluorescence microscopy successfully revealed the colocalization of IL-8 and its receptor in cells from mucosal tissues after LPS challenge in larvae 19 dph. These findings underscore the efficacy of LPS immersion as a method to activate the innate immune system in trout larvae. Furthermore, we propose IL-8 and its receptor as molecular markers for evaluating immunostimulation in the early developmental stages of salmonids.

Background & aimsThe stimulator of interferon genes (STING)/TANK-binding kinase 1 (TBK1) pathway is vital in mediating innate immune and inflammatory responses during oxidative/endoplasmic reticulum (ER) stress. However, it remains unknown whether macrophage thioredoxin-interacting protein (TXNIP) may regulate TBK1 function and cell death pathways during oxidative/ER stress.MethodsA mouse model of hepatic ischaemia/reperfusion injury (IRI), the primary hepatocytes, and bone marrow-derived macrophages were used in the myeloid-specific TXNIP knockout (TXNIPM-KO) and TXNIP-proficient (TXNIPFL/FL) mice.ResultsThe TXNIPM-KO mice were resistant to ischaemia/reperfusion (IR) stress-induced liver damage with reduced serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) levels, macrophage/neutrophil infiltration, and pro-inflammatory mediators compared with the TXNIPFL/FL controls. IR stress increased TXNIP, p-STING, and p-TBK1 expression in ischaemic livers. However, TXNIPM-KO inhibited STING, TBK1, interferon regulatory factor 3 (IRF3), and NF-κB activation with interferon-β (IFN-β) expression. Interestingly, TXNIPM-KO augmented nuclear factor (erythroid-derived 2)-like 2 (NRF2) activity, increased antioxidant gene expression, and reduced macrophage reactive oxygen species (ROS) production and hepatic apoptosis/necroptosis in IR-stressed livers. Mechanistically, macrophage TXNIP deficiency promoted cylindromatosis (CYLD), which colocalised and interacted with NADPH oxidase 4 (NOX4) to enhance NRF2 activity by deubiquitinating NOX4. Disruption of macrophage NRF2 or its target gene 2',5' oligoadenylate synthetase-like 1 (OASL1) enhanced Ras GTPase-activating protein-binding protein 1 (G3BP1) and TBK1-mediated inflammatory response. Notably, macrophage OASL1 deficiency induced hepatocyte apoptotic peptidase activating factor 1 (APAF1), cytochrome c, and caspase-9 activation, leading to increased caspase-3-initiated apoptosis and receptor-interacting serine/threonine-protein kinase 3 (RIPK3)-mediated necroptosis.ConclusionsMacrophage TXNIP deficiency enhances CYLD activity and activates the NRF2-OASL1 signalling, controlling IR stress-induced liver injury. The target gene OASL1 regulated by NRF2 is crucial for modulating STING-mediated TBK1 activation and Apaf1/cytochrome c/caspase-9-triggered apoptotic/necroptotic cell death pathway. Our findings underscore a novel role of macrophage TXNIP-mediated CYLD-NRF2-OASL1 axis in stress-induced liver inflammation and cell death, implying the potential therapeutic targets in liver inflammatory diseases.Lay summaryLiver inflammation and injury induced by ischaemia and reperfusion (the absence of blood flow to the liver tissue followed by the resupply of blood) is a significant cause of hepatic dysfunction and failure following liver transplantation, resection, and haemorrhagic shock. Herein, we uncover an underlying mechanism that contributes to liver inflammation and cell death in this setting and could be a therapeutic target in stress-induced liver inflammatory injury.

Astrocytes are vital support cells that ensure proper brain function. In brain disease, astrocytes reprogram into a reactive state that alters many of their cellular roles. A long-standing question in the field is whether downregulation of reactive astrocyte (RA) markers during resolution of inflammation is because these astrocytes revert back to a non-reactive state or die and are replaced. This has proven difficult to answer mainly because existing genetic tools cannot distinguish between healthy versus RAs. Here we describe the generation of an inducible genetic tool that can be used to specifically target and label a subset of RAs. Longitudinal analysis of an acute inflammation model using this tool revealed that the previously observed downregulation of RA markers after inflammation is likely due to changes in gene expression and not because of cell death. Our findings suggest that cellular changes associated with astrogliosis after acute inflammation are largely reversible.