LPS-induced Sepsis Research Articles

The Effects of Agomelatine Treatment on Lipopolysaccharide-Induced Septic Lung Injuries in Rats.

We designed an experimental model of sepsis in rats to investigate the effects of agomelatine (AGO) on lung tissues using molecular and histopathological methods. In our experimental model, the 32 rats were divided into 4 groups: group 1: control group (HEALTHY); group 2: lipopolysaccharide group (LPS); group 3: LPS plus 50 mg/kg AGO group (LPS + AGO50); and group 4: LPS plus 100 mg/kg AGO group (LPS + AGO100). An LPS-induced sepsis model was performed to replicate the pathology of sepsis. Rats from all 4 groups were killed after 12 hours, and their lungs were quickly collected. To investigate the therapeutic strategy, we evaluated tumor necrosis factor-alpha (TNF-α) and nuclear factor-kappa B (NF-κB) messenger RNA expressions by real-time polymerase chain reaction using molecular methods and lung tissue damage indicators using histopathological methods. The expressions of TNF-α and NF-κB were reduced in the groups treated with AGO. The histopathology results supported the molecular results. In this experimental study, we demonstrated for the first time the positive effects of AGO on LPS-induced sepsis in lung tissue using molecular and histopathological methods, indicating that it contributes to the prevention of lung damage.

LBP Protects Hepatocyte Mitochondrial Function Via the PPAR-CYP4A2 Signaling Pathway in a Rat Sepsis Model.

To explore the role of LPS binding protein (LBP) in metabolism and optimize sepsis treatment. A sepsis model was established by injecting LPS into LBP-/- rats and WT rats and observing changes in the liver over time (0, 1, 6, and 24 h). Detecting liver inflammation and injury. Optimizing the treatment of sepsis. WT rats and LBP-/- rats. We established a sepsis model by injecting LPS intravenously. First, we induced sepsis in WT and LBP-/- rats with LPS. The rats were sacrificed, and serum and liver samples were collected at 1, 6, and 24 h after LPS injection. We found that the deletion of LBP reduced LPS-induced liver inflammation and injury at 1 and 6 h. Ballooning degeneration was clearly present in LBP-/- rat livers at 24 h after LPS injection. We found that mitochondrial damage and reactive oxygen species (ROS) levels were higher in LBP-/- rat livers than in WT rat livers at 24 h after LPS injection. According to the transcriptomic results, the peroxisome proliferator-activated receptor (PPAR) pathway may be the reason for lesions in LBP-/- rats. To further investigate the function of PPARα in sepsis, we inhibited mTOR with rapamycin and examined mitochondrial injury and ROS levels. The levels of mitochondrial damage and ROS were reduced after LBP-/- rats were pretreated with rapamycin in the context of LPS-induced sepsis. Inhibiting CYP4a2, one of the PPARα-target gene products, reduced the level of LPS-induced ROS in LBP-/- rats. LBP protects hepatic mitochondria against LPS-induced damage via the LBP-PPARα-CYP4a2 signaling pathway.

Intragastric and atomized administration of canagliflozin inhibit inflammatory cytokine storm in lipopolysaccharide-treated sepsis in mice: A potential COVID-19 treatment

To date, drugs to attenuate cytokine storm in severe cases of Corona Virus Disease 2019 (COVID-19) are not available. In this study, we investigated the effects of intragastric and atomized administration of canagliflozin (CAN) on cytokine storm in lung tissues of lipopolysaccharides (LPS)-induced mice. Results showed that intragastric administration of CAN significantly and widely inhibited the production of inflammatory cytokines in lung tissues of LPS-induced sepsis mice. Simultaneously, intragastric administration of CAN significantly improved inflammatory pathological changes of lung tissues. Atomized administration of CAN also exhibited similar effects in LPS-induced sepsis mice. Furthermore, CAN significantly inhibited hypoxia inducible factor 1α (HIF-1α) and phosphofructokinase-2/fructose-2,6-bisphosphatase 3 (PFKFB3) protein levels in LPS-treated lung tissues. These results indicated that CAN might attenuate cytokine storm and reduce the inflammatory symptoms in critical cases in COVID-19. Its action mechanism might involve the regulation of HIF-1α and glycolysis in vivo. However, further studies about clinical application and mechanism analysis should be validated in the future.

Macrophage-preferable delivery of the leucine-rich repeat domain of NLRX1 ameliorates lethal sepsis by regulating NF-κB and inflammasome signaling activation

Sepsis is an acute systemic inflammatory disease triggered by bacterial infection leading organ dysfunctions that macrophages are responsible for major triggering of systemic inflammation. Treatment options are limited to antibiotics and drugs to manage the symptoms of sepsis, but there are currently no molecular-targeted therapies. Here, we identified a novel macrophage-preferable delivery peptide, C10, which we conjugated to truncated domains of NLRX1 (leucine-rich repeat region (LRR), and nucleotide binding domain (NBD)) to obtain C10-LRR and C10-NBD. Leucine rich amino acid of C10 enables macrophage preferable moieties that efficiently deliver a cargo protein into macrophages in vitro and in vivo. C10-LRR but not C10-NBD significantly improved survival in an LPS-mediated lethal endotoxemia sepsis model. C10-LRR efficiently inhibited IL-6 production in peritoneal macrophages via prevention of IκB degradation and p65 phosphorylation. In addition, C10-LRR negatively regulated IL-1β production by preventing caspase-1 activation with a sustained mitochondrial MAVS level. Finally, co-treatment with anti-TNFα antibody and C10-LRR had a synergistic effect in an LPS-induced sepsis model. Collectively, these findings indicate that C10-LRR could be an effective therapeutic agent to treat systemic inflammation in sepsis by regulating both NF-κB and inflammasome signaling activation.

Back cover story: Eur. J. Immunol. 5'21

European Journal of ImmunologyVolume 51, Issue 5 Back CoverFree Access Back cover story: Eur. J. Immunol. 5'21 First published: 05 May 2021 https://doi.org/10.1002/eji.202170058AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Abstract Our back cover features H&E stainings from the lungs of LPS-induced sepsis mice pretreated with Nitrosonisoldipine (NTS), a photodegradation product of nisoldipine. The mice displayed the alleviated lung injury. The image is taken from Chen et al. (pp. 1234–1245), where the authors show that pretreatment with NTS confers protection against sepsis in mice. NTS blocks both the non-canonical and canonical pyroptotic pathways but does not affect apoptosis. Mechanistically, as a selective caspase inhibitor, NTS could directly and irreversibly inhibit the enzyme activities of inflammatory caspases (i.e. caspase-1/-4/-11). Furthermore, NTS is safe for intraperitoneally injection in mice, suggesting that it may be used as a prototype to develop drugs for sepsis treatments. Volume51, Issue5May 2021 RelatedInformation

Colitis alters the antigen-specific response to skin commensal bacteria and predisposes to neutrophilic skin inflammation

Abstract Both gut and skin house microbial communities capable of influencing host immunity. During homeostasis, resident microbes are thought to have a dominant impact on local immune cell function. However, the prevalence of skin disorders among IBD patients suggests that this compartmentalized control may not hold under disease conditions. We hypothesize that an altered immune response to gut-resident microbes during colitis may facilitate excessive inflammation directed at skin commensals. Our lab has previously shown that colonization of neonatal mice with Staphylococcus epidermidis expressing the model antigen 2W (S. epi-2W) results in establishment of tolerance, as denoted by a higher percentage of 2W-specific regulatory T cells (Tregs) in the skin and skin-draining lymph nodes (SDLNs) and fewer skin neutrophils upon later-life S. epi-2W re-exposure. To test whether colitis perturbs tolerance to commensal skin bacteria, we colonized mice with S. epi-2W as neonates and subjected them to colitis as adults in conjunction with re-exposure. Colitic mice exhibited increased skin neutrophils and reduced percentages of S. epi-specific Tregs in skin and SDLNs compared to controls. Notably, no difference in S. epi-specific Tregs was noted in mice subjected to LPS-induced sepsis. Increased intra-intestinal presence of S. epi-2W during colitis indicates initiation of this response in the gut. Consistent with this, adoptive transfer experiments revealed a colitis-induced increase in CD4+ T cell trafficking from gut-draining LN to SDLNs. Recovery of S. epi-specific Tregs in colitic Cd4CreIl1r1flox/flox mice indicates an additional role for circulating IL-1 cytokines in shaping the skin commensal response during colitis.

Wedelolactone improves the renal injury induced by lipopolysaccharide in HK-2 cells by upregulation of protein tyrosine phosphatase non-receptor type 2.

ObjectiveTo explore the effects of wedelolactone (WEL) on sepsis-induced renal injury in the human renal proximal tubular epithelial cell line HK-2.MethodsHK-2 cells were stimulated by 1 µg/ml lipopolysaccharide (LPS) to trigger renal injury in vitro. HK-2 cells were pretreated with or without WEL (0.1, 1 and 10 µM) before LPS stimulation. Protein and mRNA analyses were performed using enzyme-linked immunosorbent assays, Western blot analysis and quantitative reverse transcription–polymerase chain reaction. The MTT assay and flow cytometry were used to measure cell viability and the rate of cell apoptosis. Protein tyrosine phosphatase non-receptor type 2 (PTPN2) knockdown was induced by the transection of HK-2 cells with short hairpin RNA.ResultsCell viability was significantly increased in a dose-dependent manner by WEL in LPS-induced HK-2 cells. WEL also decreased the levels of four inflammatory cytokines and cell apoptosis in LPS-induced HK-2 cells. The level of PTPN2 was increased after WEL treatment. PTPN2 knockdown partly abolished the inhibitory effects of WEL on cell apoptosis, the levels of inflammatory cytokines and on p38 mitogen-activated protein kinase/nuclear factor-kappaB signalling in LPS-induced HK-2 cells.ConclusionWEL improved renal injury by suppressing inflammation and cell apoptosis through upregulating PTPN2 in HK-2 cells. PTPN2 might be used as a potential therapeutic target for LPS-induced sepsis.

Discovery of chalcone analogues as novel NLRP3 inflammasome inhibitors with potent anti-inflammation activities.

NLRP3 inflammasome activation plays a critical role in inflammation and its related disorders. Herein we report a hit-to-lead effort resulting in the discovery of a novel and potent class of NLRP3 inflammasome inhibitors. Among these, the most potent lead 40 exhibited improved inhibitory potency and almost no toxicity. Further mechanistic study indicated that compound 40 inhibited the NLRP3 inflammasome activation via suppressing ROS production. More importantly, treatment with 40 showed remarkable therapeutic effects on LPS-induced sepsis and DSS-induced colitis. This study encourages further development of more potent inhibitors based on this chemical scaffold and provides a chemical tool to identify its cellular binding target.

The Effects of S-Allyl Cysteıne on Inflammatory Cascade in Lipopolysaccharide Induced Rat Sepsis Model

Lipopolysaccharide (LPS) is a main constituent of Gram-negative bacterial cell walls and is considered a leading cause of sepsis. S-allyl cysteine (SAC) is a water-soluble organosulfur component present in garlic which has a potent antioxidant and free radical scavenger activity. The purpose of this study is to examine the antioxidant and anti-inflammatory potential of SAC on endotoxin LPS-induced sepsis. Female Wistar albino rats were divided into 6 groups. LPS (5 mg/kg) was applied to rats in sepsis and treatment groups intraperitoneally. After 24 hours from LPS injection 50 mg/kg and 100 mg/kg SAC was orally administrated to treatment groups. Lung and liver 18F-fluoro-deoxy-D-glucose (18F-FDG) uptake was measured by 18FDG-PET scan. Serum levels of nuclear factor-kappa B (NF-κβ), tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase-9 (MMP-9), plasma levels of interleukin-1β (IL-1β), IL-6 and tissue levels of oxidative stress markers catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) were determined. As a result of the study, MDA and NO levels of sepsis group were significantly higher than treatment groups in lung tissue. SOD activities of sepsis group was determined to significantly lower in the liver and lung tissues than the groups which were treated with SAC. Likewise, it was concluded that serum MMP-9, TNF-α and NF-κβ levels of sepsis group was significantly higher compared to levels of treatment groups. It was determined that SAC administration reduced 18F-FDG uptake in septic rats. In conclusion, SAC was observed to diminish effects of the acute toxicity and oxidative stress formed with LPS.

Irisin Protects Against LPS-Stressed Cardiac Damage Through Inhibiting Inflammation, Apoptosis, and Pyroptosis.

Septic cardiac dysfunction remains a clinical problem due to its high morbidity and mortality. Uncontrolled cell death and excessive inflammatory response are closely related to sepsis-induced cardiac dysfunction. Irisin has been found to play cardioprotective roles in sepsis. However, there is enough uncertainty in the mechanism of irisin-mediated cardioprotection. We hypothesized that irisin may ameliorate myocardial dysfunction via reducing cardiac apoptosis, pyroptosis, and inflammation during LPS-induced sepsis. Mice were subjected to LPS with or without irisin treatment. After stimuli of LPS, the function of myocardium was distinctly impaired, which was closely related to increased level of apoptosis (decreased expression of Bcl-2 and elevated expression of Caspase-3 and Bax), pyroptosis (increased expression of Caspase1, NLR family pyrin domain containing 3 (NLRP3), and gasdermin D) and inflammatory mediators (increased level of IL-1β, TNF-α, and IL-6). This process is consistent with increased toll-like receptor 4 (TLR4)/nuclear factor-kappa B signal, apoptotic signal, and NLRP3-mediated pyroptotic signal. Activation of apoptosis and pyroptosis enhanced the expression of proinflammatory cytokines and further exacerbated septic myocardial damage. However, irisin can inhibit the expression of TLR4 and its downstream signaling molecules and also lower the level of apoptosis and pyroptosis. Besides, similar results were also found in vitro model of LPS-induced H9c2 cardiomyocyte injury. In general, irisin suppressed inflammation, apoptosis, and pyroptosis by blocking the TLR4 and NLRP3 inflammasome signalings to mitigate myocardial dysfunction in sepsis.

Role of tumor endothelial marker 1 (Endosialin/CD248) lectin-like domain in lipopolysaccharide-induced macrophage activation and sepsis in mice

Deleterious hyper-inflammation resulting from macrophage activation may aggravate sepsis and lead to lethality. Tumor endothelial marker 1 (TEM1), a type I transmembrane glycoprotein containing six functional domains, has been implicated in cancer and chronic sterile inflammatory disorders. However, the role of TEM1 in acute sepsis remains to be determined. Herein we explored the functional significance of the TEM1 lectin-like domain (TEM1D1) in monocyte/macrophage activation and sepsis using TEM1D1-deleted (TEM1LeD/LeD) transgenic mice and recombinant TEM1D1 (rTEM1D1) protein. Under stimulation with lipopolysaccharides (LPS) or several other toll-like receptor agonists, TEM1LeD/LeD macrophages produced lower levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 than wild-type TEM1wt/wt macrophages. Compared with TEM1wt/wt macrophages, LPS-macrophage binding and intracellular mitogen-activated protein kinase (MAPK)/nuclear factor (NF)-κB activation were suppressed in TEM1LeD/LeD macrophages. In vivo, TEM1D1 deletion improved survival in LPS-challenged mice with reduction of circulating TNF-α and IL-6 and alleviation of lung injury and pulmonary leukocyte accumulation. In contrast, rTEM1D1 could bind to LPS and markedly suppress LPS-macrophage binding, MAPK/NF-κB signaling in macrophages and proinflammatory cytokine production. Treatment with rTEM1D1 improved survival and attenuated circulating TNF-α and IL-6, lung injury and pulmonary accumulation of leukocytes in LPS-challenged mice. These findings demonstrated differential roles for the TEM1 lectin-like domain in macrophages and soluble TEM1 lectin-like domain in sepsis. TEM1 in macrophages mediates LPS-induced inflammation via its lectin-like domain, whereas rTEM1D1 interferes with LPS-induced macrophage activation and sepsis.

Semaphorin 3A contributes to sepsis‑induced immunosuppression by impairing CD4+ Tcell anergy.

Semaphorin 3A (Sema3A), a member of the Sema family of proteins, appears to serve an important role in sepsis and sepsis-induced immunosuppression and has been regarded as a crucial regulator involved in cellular immune response. However, the role of Sema3A in CD4+ T cell anergy during sepsis remains to be elucidated. In the present study, the cecal ligation and perforation model and lipopolysaccharide (LPS) were used to simulate sepsis and the role of Sema3A in sepsis-induced CD4+ T cell anergy was investigated in vivo and in vitro. In vivo, the serum concentration of Sema3A was enhanced and exacerbated sepsis-induced T cell immunosuppression and multiple organ dysfunction syndromes (MODS). Administration of (−)-epigallocatechin-3-gallate, an inhibitor of Sema3A, markedly improved sepsis-induced T cell immunosuppression and MODS. In vitro, both lymphoid and myeloid lineages secreted high concentration of Sema3A in LPS-induced sepsis, especially in the lymphoid lineage. Inhibition of Sema3A alleviated T cell anergy. The NF-κB signaling pathway was involved in Sema3A-mediated autocrine loop aggravating T cell immune dysfunction during LPS-induced sepsis. Inhibiting Sema3A exerted significant improvement of sepsis-induced immunosuppression and MODS, which was associated with improvement of CD4+ T cells anergy via regulation of the NF-κB signaling pathway.

C-Terminal Amination of a Cationic Anti-Inflammatory Peptide Improves Bioavailability and Inhibitory Activity Against LPS-Induced Inflammation.

Lipopolysaccharide (LPS) has been implicated as a major cause of inflammation and an uncontrolled LPS response increases the risk of localized inflammation and sepsis. While some native peptides are helpful in the treatment of LPS-induced inflammation, the use of these peptides is limited due to their potential cytotoxicity and poor anti-inflammatory activity. Hybridization is an effective approach for overcoming this problem. In this study, a novel hybrid anti-inflammatory peptide that combines the active center of Cathelicidin 2 (CATH2) with thymopentin (TP5) was designed [CTP, CATH2 (1–13)-TP5]. CTP was found to have higher anti-inflammatory effects than its parental peptides through directly LPS neutralization. However, CTP scarcely inhibited the attachment of LPS to cell membranes or suppressed an established LPS-induced inflammation due to poor cellular uptake. The C-terminal amine modification of CTP (CTP-NH2) was then designed based on the hypothesis that C-terminal amidation can enhance the cell uptake by increasing the hydrophobicity of the peptide. Compared with CTP, CTP-NH2 showed enhanced anti-inflammatory activity and lower cytotoxicity. CTP-NH2 not only has strong LPS neutralizing activity, but also can significantly inhibit the LPS attachment and the intracellular inflammatory response. The intracellular anti-inflammatory effect of CTP-NH2 was associated with blocking of LPS binding to the Toll-like receptor 4-myeloid differentiation factor 2 complex and inhibiting the nuclear factor-kappa B pathway. In addition, the anti-inflammatory effect of CTP-NH2 was confirmed using a murine LPS-induced sepsis model. Collectively, these findings suggest that CTP-NH2 could be developed into a novel anti-inflammatory drug. This successful modification provides a design strategy to improve the cellular uptake and anti-inflammatory activity of peptide agents.

MiR-128-3p inhibits apoptosis and inflammation in LPS-induced sepsis by targeting TGFBR2.

BackgroundSepsis is a systemic inflammatory response that can lead to the dysfunction of many organs. The aberrant expression of miRNAs is associated with the pathogenesis of sepsis. However, the biological functions of miR-128-3p in sepsis remain largely unknown, and its mechanism should be further investigated. This study aimed to determine the regulatory network of miR-128-3p and TGFBR2 in lipopolysaccharide (LPS)-induced sepsis.MethodsThe expression levels of miR-128-3p and transforming growth factor beta receptors II (TGFBR2) were detected by quantitative polymerase chain reaction (qPCR). The protein levels of TGFBR2, Bcl-2, Bax, cleaved caspase 3, Smad2, and Smad3 were measured by western blot. Cell apoptosis was analyzed by flow cytometry. Cytokine production was detected by enzyme-linked immunosorbent assay (ELISA). The binding sites of miR-128-3p and TGFBR2 were predicted by Targetscan online software and confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay.ResultsThe level of miR-128-3p was decreased, and TGFBR2 expression was increased in serum samples of sepsis patients and LPS-induced HK2 cells. Overexpression of miR-128-3p or knockdown of TGFBR2 ameliorated LPS-induced inflammation and apoptosis. Moreover, TGFBR2 was a direct target of miR-128-3p, and its overexpression reversed the inhibitory effects of miR-128-3p overexpression on inflammation and apoptosis in LPS-induced HK2 cells. Besides, overexpression of miR-128-3p downregulated TGFBR2 to suppress the activation of the Smad signaling pathway.ConclusionmiR-128-3p could inhibit apoptosis and inflammation by targeting TGFBR2 in LPS-induced HK2 cells, which might provide therapeutic strategy for the treatment of sepsis.

Transcription factor Sp1 ameliorates sepsis-induced myocardial injury via ZFAS1/Notch signaling in H9C2 cells

PurposeTo investigate whether Sp1 can ameliorate sepsis-induced myocardial injury and explore the potential molecular mechanism. MethodsThe embryonic cardiomyocyte cell line H9C2 and primary cultured mouse neonatal cardiomyocytes (CMNCs) were treated with LPS or phosphate-buffered saline (PBS). A mouse model of LPS-induced sepsis was established using male C57BL/6J mice and their cardiomyocytes were collected. Real-time reverse transcription-PCR (qRT-PCR) assay was used to detect the expression levels of Sp1 and ZFAS1 in cardiomyocytes. Western blotting analysis was used to assess the protein expression levels of Sp1, apoptosis-associated proteins and Notch signaling pathway related proteins. Luciferase assay was used to detect the interaction between Sp1 and ZFAS1. Cell transfection was used to generate H9C2 cells with overexpressed or knocked down of Sp1 or ZFAS1. MTT assay and flow cytometry analysis were used to test the cell proliferation and cell apoptosis ratio. ResultsOur data revealed that the expressions of ZFAS1 and Sp1 were significantly reduced in LPS-treated H9C2 cells and primary CMNCs. The downregulation of ZFAS1 and Sp1 were also found in cardiomyocytes obtained from LPS-challenged mice. LPS induced H9C2 cell apoptosis and depressed cell proliferation was ameliorated by ZFAS1 overexpression and aggravated by ZFAS1 knockdown. Mechanistically, Luciferase assay indicated that Sp1 could bind to ZFAS1, and positively regulated ZFAS1 expression. Moreover, Notch signaling pathway participates in H9C2 cell apoptosis mediated by Sp1. ConclusionThe present study demonstrates that Sp1 regulates LPS-induced cardiomyocyte apoptosis via ZFAS1/Notch signaling pathway, which may serve as therapeutic targets for sepsis-induced myocardial injury.

Comparison of response to LPS-induced sepsis in three DBA/2 stocks derived from different sources

Sepsis, one of the most fatal diseases in the world, is known to culminate in multiple organ failure due to an uncontrolled inflammatory response. Hence, the use of animal models in sepsis research is very important to study complex immune responses. The current study was undertaken to compare commercial stocks with KFDA stocks of DBA/2 mice as an animal model for sepsis study. To compare responses of DBA/2 mice to lipopolysaccharides (LPS)-induced sepsis, we measured altered characteristics of various factors associated with sepsis, including survival curves, organ failure and inflammatory response, in DBA/2Korl stock and two commercial stocks (DBA/2A and DBA/2B). Survival rates after LPS exposure were similar for DBA/2Korl and DBA/2B; however, for times over 20 h, survival rates were reduced and concentration dependent in DBA/2A. In order to evaluate multiple organ failure caused by sepsis, H&E stains were evaluated for liver and spleen tissues obtained in the early (2 h) and later (20 h) stages after exposure to LPS; no significant differences were observed between the three stocks. mRNA and protein levels of proinflammatory cytokines were assessed for evaluating inflammatory reactions, and were found to increase in a dose-dependent manner in most DBA/2 mice after LPS treatment. However, no changes were observed in the mRNA levels of proinflammatory cytokines at 20 h after LPS exposure in the DBA/2A stock. The induction of inflammation-mediated factors by LPS exposure did not induce alterations in the mRNA levels of COX-2 and iNOS in all three DBA/2 stocks. Our results indicate that response of DBA/2Korl to LPS-induced sepsis is similar to the two commercial DBA/2 stocks, thus representing its potential as a useful biological resource established in Korea.

Anti‐Interleukin‐16 Neutralizing Antibody Treatment Alleviates Sepsis‐Induced Cardiac Injury and Dysfunction via the Nuclear Factor Erythroid‐2 Related Factor 2 Pathway in Mice

Several interleukin (IL) members have been reported to participate in sepsis. In this study, the effects of IL-16 on sepsis-induced cardiac injury and dysfunction were examined, and the related mechanisms were detected. IL-16 expression in septic mice was first measured, and the results showed that both cardiac and serum IL-16 expression levels were increased in mice with sepsis induced by LPS or cecal ligation and puncture (CLP) compared with control mice. Then, IL-16 was neutralized, and the effects on lipopolysaccharide- (LPS-) induced cardiac injury were detected. The results showed that an anti-IL-16 neutralizing antibody (nAb) significantly reduced mortality and increased serum lactate dehydrogenase (LDH), creatine kinase myocardial bound (CK-MB), and cardiac troponin T (cTnT) levels while improving cardiac function in mice with LPS-induced sepsis. Neutralization of IL-16 also increased the activation of antioxidant pathways and the expression of antioxidant factors in septic mice while decreasing the activation of prooxidant pathways and the expression of prooxidants. Treatment with the anti-IL-16 nAb increased mitochondrial apoptosis-inducing factor (AIF) expression, decreased nuclear AIF and cleaved poly-ADP-ribose polymerase (PARP) expression, and decreased TUNEL-positive cell percentages in LPS-treated mice. Additionally, treatment with CPUY192018, the nuclear factor erythroid-2 related factor 2 (Nrf2) pathway, significantly increased mortality and reversed the above effects in mice treated with LPS and the anti-IL-16 nAb. Our results showed that the anti-IL-16 nAb regulates oxidative stress through the Nrf2 pathway and participates in the regulation of cardiac injury in septic mice. Neutralization of IL-16 may be a beneficial strategy for the prevention of cardiac injury and dysfunction in sepsis patients.

ALKBH8 Suppresses Oxidative Stress and Ameliorates Inflammation via Blocking NFκB/NLRP3 Axis in Sepsis

Sepsis is the most common cause of acute kidney injury (AKI), which is associated with increased morbidity and mortality. The molecular mechanisms underlying sepsis pathogenesis and its regulation are incompletely understood. Here we demonstrated that human AlkB homologue, ALKBH8, plays a critical role in sepsis. We found that ALKBH8 expression was down-regulated in patients with acute sepsis. Low expression of ALKBH8 was also confirmed in LPS-induced sepsis model. Functionally, we revealed that knockdown of ALKBH8 in THP-1 cells suppressed cell proliferation and promoted cell apoptosis. In contrast, overexpression of ALKBH8 enhanced cell viability and protected against oxidative damage in THP-1 cells. In addition, we demonstrated that knockdown of ALKBH8 enhanced oxidative stress and decreased selenocysteine-protein expression. Mechanistically, we found that ALKBH8 ameliorated inflammation response via blocking NFκB/NLRP3 signaling in THP-1 cells. Inhibition of ROS production by using N -acetylcysteine (NAC) antagonized the effect of ALKBH8 knockdown on inflammation response and NFκB/NLRP3 signaling activation in THP-1 cells. Taken together, these results strongly suggest that ALKBH8 is an important oxidative stress and inflammation regulator in sepsis, which might have potential clinical application in the treatment of sepsis. Ethics: All patients provided written informed consent and the study protocols were approved by the Ethics Committee of Xiʹan Jiaotong University. The investigation conforms to the principles outlined in the Declaration of Helsinki and written informed consent was obtained from all participants. Funding: The work was supported by Key Research and Development Projects of Shaanxi Province of China (2020SF-121) Shaanxi Administration of Traditional Chinese Medicine Research Program (JCMS037). Competing interests: None

Vancomycin and daptomycin modulate the innate immune response in a murine model of LPS-induced sepsis.

Sepsis is a leading cause of death worldwide, despite the use of multimodal therapies. Common antibiotic regimens are being affected by a rising number of multidrug-resistant pathogens, and new therapeutic approaches are therefore needed. Antibiotics have immunomodulatory properties which appear to be beneficial in the treatment of sepsis. We hypothesized that the last-resort antibiotics vancomycin (VAN) and daptomycin (DMC) modulate cell migration, phagocytosis, and protein cytokine levels in a murine model of lipopolysaccharide (LPS)-induced sepsis. Ten to twelve-week-old C57BL/6 mice (n = 4–6 animals per group) were stimulated with LPS for 20 h, followed by the administration of VAN or DMC. The outcome parameters were leukocyte accumulation and effector function. Quantification of the immune cells in the peritoneal lavage was performed using flow cytometry analysis. Phagocytosis was measured using pHrodo E. coli BioParticles. The response of the cytokines TNFα, IL-6, and IL-10 was measured in vitro using murine peritoneal macrophages stimulated with LPS and VAN or DMC. VAN decreased both the peritoneal macrophage and the dendritic cell populations following LPS stimulation. DMC reduced the dendritic cell population in the peritoneal cavity in LPS-infected mice. Both antibiotics increased the phagocytic activity in peritoneal macrophages, but this effect was diminished in response to LPS. Phagocytosis of dendritic cells was increased in LPS-infected animals treated with VAN. VAN and DMC differently modulated the levels of pro-and anti-inflammatory cytokines. In a murine model of LPS-induced sepsis, VAN and DMC exhibit immunomodulatory effects on cells involved in innate immunity. The question of whether these antibiotics exhibit synergistic effects in the treatment of septic patients, beyond their bactericidal properties, should be further evaluated in future studies.

Kombucha ameliorates LPS-induced sepsis in a mouse model.

As a popular traditional fermented beverage, kombucha has been extensively studied for its health benefits. However, the science behind the anti-inflammatory effect of kombucha has not been well studied, and there is an urgent need to uncover the secrets of the anti-inflammatory properties of kombucha. Here, we investigate kombucha's protective effects against lipopolysaccharide (LPS)-induced sepsis and on the intestinal microecology in mice. The contents of reducing sugars, polyphenols, catechins, and organic acids in the kombucha group were identified using various methods. The results showed that the concentrations of acetic acid, gluconic acid, polyphenol, and glucuronic acid in the kombucha group were 55.70 ± 2.57 g L-1, 50.20 ± 1.92 g L-1, 2.36 ± 0.31, and 1.39 ± 0.22 g L-1, respectively. The result also demonstrated that kombucha effectively improves the survival rate from 0% to 40%, and increases the thermoregulation in LPS-treated mice, which showed decreased mobility and had lost their appetite for food. Furthermore, kombucha reduced the levels of tumor necrosis factor-α and interleukins (IL)-1β and IL-6, restored the levels of T cells and macrophages in LPS-challenged mice, alleviated the histopathological damage, and inhibited NF-κB signaling in mice with LPS-induced sepsis. We demonstrated that kombucha effectively prevents cellular immune function disorder in mice at the initial stage of sepsis and exerts an immunomodulatory effect. In addition, the effect of kombucha on the gut microbiota was investigated during sepsis. Kombucha supplementation altered the diversity of the gut microbiota and promoted the growth of butyrate-producing bacteria, which exert anti-inflammatory effects. Our results illustrate the potential of kombucha as a novel anti-inflammatory agent against the development of systemic inflammatory responses associated with sepsis.