Despite advances in research, studies on predictive models for Non-Alcoholic Fatty Liver Disease (NAFLD)-related fibrosis remain limited. Identifying new biomarkers to distinguish Non-Alcoholic Steatohepatitis (NASH) from NAFLD would aid in the treatment of NASH. Gene expression and clinical profiles of NAFL and NASH patients were collected from databases. Differentially expressed genes with prognostic value were used to construct predictive model. Validation of fibrosis stage-related pyroptosis-related genes (PRGs) was performed using Sprague-Dawley rats liver fibrosis models induced by CCl4 or PS. Immune cell infiltration assessment demonstrated that stromal score, immune score, and ESTIMATE score were higher in patients with NASH compared to those with NAFL. BAX, BAK1, PYCARD, and NLRP3 were identified as hub genes that exhibit a strong correlation with fibrosis stage. Additionally, the expression of these genes was increased in fibrotic liver tissues induced by CCl4 and PS. The pyroptosis-associated gene signature effectively predicts the degree of liver fibrosis in NASH patients. Our study indicates that BAX, BAK1, PYCARD, and NLRP3 might serve as biomarkers for NASH-associated fibrosis.

Damage-associated molecular patterns (DAMPs) are a cause of Crohn’s disease (CD). Peroxiredoxin 1 (Prdx1), a newly identified DAMP, plays a critical role in organ injury with its potent proinflammatory properties. However, its specific role in CD remains unclear. Here, we identify serum Prdx1 as a DAMP involved in CD. Serum Prdx1 levels were significantly increased and positively correlated with the severity of intestinal inflammation in both CD patients and mice with experimental colitis. Genetic knockout of Prdx1 or administration of a Prdx1-neutralizing antibody attenuated colitis in mice, as evidenced by restoration of the colonic epithelium, improved disease activity, and reduced colonic inflammation. These protective effects were impaired by introduction of recombinant Prdx1 (rPrdx1). Mechanistically, Prdx1 exacerbated intestinal inflammation by promoting macrophage infiltration and subsequent cytokine production. Depletion of macrophages abolished the rPrdx1-mediated exacerbation of colitis. Further, rPrdx1 was internalized by macrophages, leading to lysosomal disruption and subsequent activation of the NLRP3 inflammasome. Pharmacological inhibition of NLRP3 effectively abrogated rPrdx1-induced exacerbation of colitis. In conclusion, serum Prdx1 promotes intestinal inflammation in CD at least in part by activating the NLRP3 inflammasome through lysosomal disruption in macrophages. These findings highlight the pathogenic role of Prdx1 in CD and reveal therapeutic potential of managing CD via neutralization of circulating Prdx1.

Hypoxia can induce pathological alterations to the kidneys, such as activation of inflammatory signaling pathways. This form of inflammation is pathogen-free and is referred to as aseptic inflammation. Currently, the mechanisms leading to aseptic inflammation under hypoxia are not well understood. Emerging evidence has indicated that Prdx1, a member of the peroxidase family, contributes to the development of various diseases by stimulating aseptic inflammation. This study was conducted to reveal the potential role of Prdx1 in the pathogenesis of hypoxia-induced renal injury. A mouse model of systemic hypoxia was developed, which revealed that Prdx1 levels were elevated in injured kidneys and peripheral circulation. A comparable increase was also observed in hypoxia-treated immortalized bone marrow-derived macrophages (iBMDM). Knock-down of Prdx1 in mice caused a significant reduction in renal tissue injury and inflammation induced by hypoxic injury. In addition, we demonstrated that Prdx1 modulates inflammatory responses by activating the TLR4/MAPK/NF-κB signaling pathways. Recombinant Prdx1 promoted the activation of these pathways in macrophages, whereas genetic knockout of Prdx1 or pharmacological inhibition suppressed their activity. Altogether, we found a previously unrecognized role for Prdx1 in the regulation of inflammation in hypoxia-induced renal injury. These findings suggest that Prdx1 can be a potential target for treating this severe disease.

Damage-associated molecular patterns (DAMPs) are a cause of acute kidney injury (AKI). Our knowledge of these DAMPs remains incomplete. Here, we report serum peroxiredoxin 1 (Prdx1) as a novel DAMP for AKI. Lipopolysaccharide (LPS) and kidney ischemia/reperfusion injury instigated AKI with concurrent increases in serum Prdx1 and reductions of Prdx1 expression in kidney tubular epithelial cells. Genetic knockout of Prdx1 or use of a Prdx1-neutralizing antibody protected mice from AKI and this protection was impaired by introduction of recombinant Prdx1 (rPrdx1). Mechanistically, lipopolysaccharide increased serum and kidney proinflammatory cytokines, macrophage infiltration, and the content of M1 macrophages. All these events were suppressed in Prdx1-/-mice and renewed upon introduction of rPrdx1. In primary peritoneal macrophages, rPrdx1 induced M1 polarization, activated macrophage-inducible C-type lectin (Mincle) signaling, and enhanced proinflammatory cytokine production. Prdx1 interacted with Mincle to initiate acute kidney inflammation. Of note, rPrdx1 upregulated Mincle and the spleen tyrosine kinase Syk system in the primary peritoneal macrophages, while knockdown of Mincle abolished the increase in activated Syk. Additionally, rPrdx1 treatment enhanced the downstream events of Syk, including transcription factor NF-KB signaling pathways. Furthermore, serum Prdx1 was found to be increased in patients with AKI; the increase of which was associated with kidney function decline and inflammatory biomarkers in patient serum. Thus, kidney-derived serum Prdx1 contributes to AKI at least in part by activating Mincle signaling and downstream pathways.

Ulcerative colitis is a chronic inflammatory bowel disorder that is hard to cure once diagnosed. Bisdemethoxycurcumin has shown positive effects on inflammatory diseases. However, the underlying bioactive interaction between bisdemethoxycurcumin and ulcerative colitis is unclear. The objective of this study was to determine the core target and potential mechanism of action of bisdemethoxycurcumin as a therapy for ulcerative colitis. The public databases were used to identify potential targets for bisdemethoxycurcumin and ulcerative colitis. To investigate the potential mechanisms, the protein-protein interaction network, gene ontology analysis, and Kyoto encyclopedia of genes and genomes analysis have been carried out. Subsequently, experimental verification was conducted to confirm the findings. A total of 132 intersecting genes of bisdemethoxycurcumin, as well as ulcerative coli-tis-related targets, were obtained. SRC, EGFR, AKT1, and PIK3R1 were the targets of highest potential, and the PI3K/Akt and MAPK pathways may be essential for the treatment of ulcerative colitis by bisdemethoxycurcumin. Molecular docking demonstrated that bisdemethoxycurcumin combined well with SRC, EGFR, PIK3R1, and AKT1. Moreover, the in vitro experiments suggested that bisdemethoxycurcumin might reduce LPS-induced pro-inflammatory cytokines levels in RAW264.7 cells by suppressing PI3K/Akt and MAPK pathways. Our study provided a comprehensive overview of the potential targets and molecular mechanism of bisdemethoxycurcumin against ulcerative colitis. Furthermore, it also provided a theoretical basis for the clinical treatment of ulcerative colitis, as well as compelling evidence for further study on the mechanism of bisdemethoxycurcumin in the treatment of ulcerative colitis.

Despite the increasing understanding of the pathophysiology of hepatic fibrosis, the therapies to combat it remain inadequate. Fluorofenidone (AKF-PD) is a novel pyridone agent able to ameliorate hepatic fibrosis in an experimental hepatic fibrosis model induced by dimethylnitrosamine. However, the underlying mechanism remains to be further elucidated. In light of the critical role of the NF-κB pathway in inflammation and hepatic fibrosis, together with the preliminary finding that AKF-PD decreases the release of proinflammatory cytokines in the endotoxemia and unilateral ureteral occlusion model, the aim of this study was to explore whether AKF-PD exerts an antifibrotic effect in hepatic fibrosis by inhibiting inflammation and suppressing the activation of the NF-κB pathway in vivo and in vitro. To test this possibility, the effect of AKF-PD on hepatic fibrosis models induced by both carbon tetrachloride (CCL4 ) and porcine serum (PS) was investigated. Our results showed that AKF-PD treatment ameliorated hepatic injury and fibrosis in both models. Furthermore, the administration of AKF-PD induced a robust anti-inflammatory reaction revealed by the downregulation of the proinflammatory cytokines as well as the suppression of the infiltration of inflammatory cells in the fibrotic liver. The analysis of the mechanism of action demonstrated that the attenuation of the production of proinflammatory cytokines and chemokines mediated by AKF-PD in vivo and in vitro were accompanied by the suppression in the activation of the NF-κB signaling pathway. In conclusion, AKF-PD might be considered as an antifibrotic agent attenuating hepatic inflammation and fibrosis potentially through the suppression of the NF-κB pathway.

In response to microbes and other danger signals, the NLRP3 inflammasome in immune cells triggers the activation of the protease caspase-1, which mediates the maturation of the inflammatory cytokine IL-1β. Here, we investigated how the NLRP3 inflammasome is regulated. We found that its activation in primary mouse macrophages induced the Src family kinase Lyn to phosphorylate NLRP3 at Tyr918, which correlated with a subsequent increase in its ubiquitination that facilitated its proteasome-mediated degradation. NLRP3 tyrosine phosphorylation and ubiquitination was abrogated in Lyn-deficient macrophages, which produced increased amounts of IL-1β. Furthermore, mice lacking Lyn were more susceptible to LPS-induced septic shock in an NLRP3-dependent manner. Our data demonstrate that Lyn-mediated tyrosine phosphorylation is a prerequisite for the ubiquitination that dampens NLRP3 inflammasome activity.

Aberrant NLRP3 inflammasome activation contributes to the development of endotoxemia. The importance of negative regulation of NLRP3 inflammasomes remains poorly understood. Here, we show that the E3 ubiquitin ligase Cbl-b is essential for preventing endotoxemia induced by a sub-lethal dose of LPS via a caspase-11/NLRP3-dependent manner. Further studies show that NLRP3 undergoes both K63- and K48-linked polyubiquitination. Cbl-b binds to the K63-ubiquitin chains attached to the NLRP3 leucine-rich repeat domain (LRR) via its ubiquitin-associated region (UBA) and then targets NLRP3 at K496 for K48-linked ubiquitination and proteasome-mediated degradation. We also identify RNF125 as an additional E3 ubiquitin ligase that initiates K63-linked ubiquitination of the NLRP3 LRR domain. Therefore, NLRP3 is sequentially ubiquitinated by K63- and K48-linked ubiquitination, thus keeping the NLRP3 inflammasomes in check and restraining endotoxemia.

Cyclic GMP-AMP synthase (cGAS) is a cytosolic DNA sensor that activates type 1 IFN response via cGAS/cGAMP/STING-dependent pathway to defend against viral and bacterial infections. The role of c-GAS in adaptive immunity is completely unknown. In this study, we attempted to determine whether cGAS also regulates T cell responses using mice deficient for cGAS. We found that cGas−/− mice develop ameliorated experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis, which correlates with defective Th1/Th17 responses. This reduced disease activity in cGas−/− mice is unlikely due to the expression cGAS in T cells because Rag1−/− recipients receiving Wild-type and cGas−/− CD4+ T cells develop a comparable degree of EAE. Therefore, our data suggest that cGAS expression in innate immune cells may indirectly regulate pathogenic Th1/Th17 responses during EAE induction.

An amendment to this paper has been published and can be accessed via the original article.

Abstract T follicular helper cells (Tfh) are critical in providing help to B cells, and have been shown to be involved in the overproduction of pathogenic auto-Abs and tissue damage in lupus. Cbl-b, a RING finger E3 ubiquitin ligase, negatively regulates lymphocyte activation. In this study, we found that the expression of Cbl-b in CD4+ T cells from lpr mice on a C57BL/6 background (B6-lpr) was down-regulated. Introducing Cbl-b deficiency or Cbl-b C373A mutation into B6-lpr mice significantly exacerbated the onset of the disease in B6-lpr mice, which correlated with heightened serum auto-antibody titers, exaggerated Tfh, GC B cells, and plasma cells. These data indicate that Cbl-b negatively regulates lupus disease progression and Tfh development via its E3 ubiquitin ligase activity. In support of a critical role of Cbl-b in Tfh development, mice specifically deficient for Cbl-b in T cells also exhibited an increase in Tfh when they were immunized with OVA in CFA. Mechanistically, Cbl-b appeared to specifically bind to Bcl6, and target Bcl-6 for ubiquitination and degradation. In strong support of Cbl-b in exaggerated Tfh in lupus, we found that Tfh cells were increased in the peripheral blood of SLE patients. Furthermore, Cbl-b expression was significantly reduced in Tfh from patient with SLE. Therefore, our data indicate that Cbl-b suppresses Tfh development by targeting Bcl6, and that deregulated expression of Cbl-b may play a crucial in aberrant Tfh development, thus eliciting pathogenic auto-Ab production by B cells.

The aim of the present research was to study the therapeutic impacts of fluorofenidone (AKF-PD) on pig serum (PS)-induced liver fibrosis in rats and the complex molecular mechanisms of its effects on hepatic stellate cells (HSCs). Wistar rats were randomly divided into normal control, PS and PS/AKF-PD treatment groups. The activated human HSC LX-2 cell line was also treated with AKF-PD. The expression of collagen I and III, and α-smooth muscle actin (α-SMA) was determined by immunohistochemical staining and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blotting and/or RT-qPCR analyses were used to determine the expression of transforming growth factor (TGF)-β1, α-SMA, collagen I, mothers against decapentaplegic homolog (Smad)-3, extracellular signal-regulated kinase (ERK)1/2, p38 mitogen-activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (JNK). AKF-PD attenuated the degree of hepatic fibrosis and liver injury in vivo, which was associated with the downregulation of collagen I and III, and α-SMA at the mRNA and protein levels. In vitro, AKF-PD treatment significantly reduced the TGF-β1-induced activation of HSCs, as determined by the reduction in collagen I and α-SMA protein expression. The TGF-β1-induced upregulation of the phosphorylation of Smad 3, ERK1/2, p38 and JNK was attenuated by AKF-PD treatment. These findings suggested that AKF-PD attenuated the progression of hepatic fibrosis by suppressing HSCs activation via the TGF-β1/Smad and MAPK signaling pathways, and therefore that AKF-PD may be suitable for use as a novel therapeutic agent against liver fibrosis.

Sterile inflammation is initiated by damage-associated molecular patterns (DAMPs) and a key contributor to acute liver injury (ALI). However, the current knowledge on those DAMPs that activate hepatic inflammation under ALI remains incomplete. We report here that circulating peroxiredoxin-1 (Prdx1) is a novel DAMP for ALI. Intraperitoneal injection of acetaminophen (APAP) elicited a progressive course of ALI in mice, which was developed from 12 to 24 h post injection along with liver inflammation evident by macrophage infiltration and upregulations of cytokines (IL-1 beta,IL-6 and TNF-alpha); these alterations were concurrently occurred with a robust and progressive production of serum Prdx1. Similar observations were also obtained in carbon tetrachloride (CCl4)-induced ALI in mice. Removal of the source of serum Prdx1 protected mice deficient in Prdx1 from APAP and CCl4-induced liver injury, and decreased macrophage infiltration, IL-1 beta, IL-6 and TNF-alpha production. As a result, Prdx1(-/-) mice were strongly protected from APAP-induced death that was likely progressed from ALI. Additionally, intravenous re-introduction of recombinant Prdx1 (rPrdx1) in Prdx1(-/-) mice reversed or reduced all the above events, demonstrating an important contribution of circulating Prdx1 to ALI. rPrdx1 potently induced in primary macrophages the expression of pro-IL-1 beta, IL-6, TNF-alpha, and IL-1 beta through the NF-kappa B signaling as well as the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome signaling, evident by caspase-1 activation. Furthermore, a significant elevation of serum Prdx1 was demonstrated in patients (n = 15) with ALI; the elevation is associated with ALI severity. Collectively, we provide the first demonstration for serum Prdx1 contributing to ALI.

Objective To investigate effects of pirfenidone（PFD） on diabetic nephropathy model in db/db mice and to explore its possible mechanisms. Methods （1） Wildtype mice were as the normal control group,and db/db mice were divided into model group and PFD group,with6 mice in each group. In the PFD group mice were administered continuously by 250 mg·kg -1 ·d -1 PFD for

背景:炎症性肠病(IBD)的发生、发展与饮食关系密切,食物不耐受在IBD中的发生情况及其与IBD的关系尚不十分清楚.目的:探讨活动期克罗恩病(CD)和溃疡性结肠炎(UC)患者中食物不耐受的差异.方法:选取2016年1月-2017年11月中南大学湘雅医院确诊的活动期134例CD、67例UC患者和42名正常对照者.以ELISA法检测14种食物的血清特异性IgG,据此评价食物不耐受情况,分析CD和UC患者食物不耐受的差异.结果:CD和UC患者食物不耐受阳性率均显著高于对照组(P＜0.001),CD患者又明显高于UC患者(P ＜0.001).三组间食物不耐受程度相比差异有统计学意义(F =46.707,P＜0.001).CD患者4种和6种食物不耐受的发生率均明显高于UC患者(P＜0.001).与UC患者相比,病变累及结肠的CD患者的食物不耐受率无明显差异(P =0.100),而累及小肠的CD患者明显升高(P =0.010).多元Logistic回归分析显示,食物不耐受≥4种为病变累及小肠的CD的危险因素(P =0.040).结论:CD和UC患者的食物不耐受阳性率均明显高于对照组,CD患者食物不耐受发生率高、程度重、种类多,病变累及小肠的CD患者的食物不耐受发生率明显高于结肠型CD和UC患者,食物不耐受≥4种可能为小肠型CD的预测因素.

Helicobacter pylori (H. pylori) infection is highly associated with the occurrence of gastrointestinal diseases, including gastric inflammation, peptic ulcer, gastric mucosa-associated lymphoid-tissue lymphoma and gastric cancer. It is a key strategy to prevent and treat these diseases by eradicating H. pylori. Due to the increasing rates of antimicrobial resistance of clarithromycin and metronidazole, the eradication rate of standard triple therapy is less than 80% in recent years. On the basis of traditional triple therapy, combination with some treatments, such as probiotics, mucoprotective agents, Chinese medicine and oral clean, can improve the H. pylori eradication rate.