Wogonin ameliorates the proliferation, inflammatory response, and pyroptosis in keratinocytes via NOD-like receptor family pyrin domain containing 3/Caspase-1/Gasdermin-D pathway.

BACKGROUND: Psoriasis refers to a highly prevalent and immunologically mediated dermatosis with considerable deterioration in life quality. Wogonin, a sort of flavonoid, has been mentioned to elicit protective activities in skin diseases. However, whether Wogonin is implicated in the treatment of psoriasis and its specific mechanisms are not fully understood. AIM: The present work attempted to elaborate the role of Wogonin during the process of psoriasis and to concentrate on the associated action mechanism. METHODS: Cell counting kit-8 (CCK-8) method was initially applied to assay the viability of human keratinocyte HaCaT cells treated by varying concentrations of Wogonin. To mimic psoriasis in vitro, HaCaT cells were exposed to M5 cytokines. CCK-8 and 5-Ethynyl-2'-deoxyuridine  assays were adopted for the measurement of cell proliferation. Inflammatory levels were examined with enzyme-linked immunosorbent assay. Immunofluorescence staining tested nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) and Caspase-1 expressions. Western blot examined the protein expressions of proliferation-, inflammation-, pyroptosis-associated factors, and NLRP3. RESULTS: Wogonin treatment antagonized the proliferation, inflammatory response, and NLRP3/caspase-1/Gasdermin-D (GSDMD)-mediated pyroptosis in M5-challenged HaCaT cells. Besides, NLRP3 elevation partially abrogated the effects of Wogonin on M5-induced proliferation, inflammatory response, and NLRP3/caspase-1/GSDMD-mediated pyroptosis in HaCaT cells. CONCLUSION: In a word, Wogonin might exert anti-proliferation, anti-inflammatory and anti-pyroptosis activities in M5-induced cell model of psoriasis and the blockade of NLRP3/Caspase-1/GSDMD pathway might be recognized as a potential mechanism underlying the protective mechanism of Wogonin in psoriasis, suggesting Wogonin as a prospective anti-psoriasis drug.

Role and mechanism of endoplasmic reticulum stress and NLRP3 inflammasome in acute kidney injury. / å† è´¨ç½‘åº”æ¿€å’ŒNLRP3ç‚Žç—‡å°ä½“åœ¨æ€¥æ€§è‚¾æŸä¼¤ä¸­çš„ä½œç”¨åŠå ¶æœºåˆ¶.

Acute kidney injury (AKI) is a common critical condition in clinical practice, characterized by a rapid decline in renal function within a short period. The pathogenesis of AKI is complex and has not been fully elucidated. In recent years, studies have found that the activation of endoplasmic reticulum stress (ERS) and the Nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome are closely related to the occurrence of AKI. When the kidneys is damaged, the internal environment of the kidney cells is disrupted, leading to the activation of ERS. Excessive ERS can induce apoptosis of renal cells, leading to the occurrence of AKI. Additionally, the NLRP3 inflammasome can mediate the recognition of endogenous and exogenous danger signal molecules by the host, subsequently activating caspase-1, pro-inflammatory cytokines such as IL-1ß and IL-18, inducing inflammatory responses, and promoting apoptosis of renal cells. In animal models of AKI, the upregulation of ERS markers is often accompanied by increased expression levels of NLRP3 inflammasome-related proteins, indicating that ERS can regulate the activation process of the NLRP3 inflammasome. Clarifying the role and mechanism of ERS and NLRP3 inflammasome in AKI is expected to provide new insights for the prevention and treatment of AKI.

Local complement activation and modulation in mucosal immunity.

The complement system is an evolutionarily conserved arm of innate immunity, which forms one of the first lines of host response to pathogens and assists in the clearance of debris. A deficiency in key activators/amplifiers of the cascade results in recurrent infection, whereas a deficiency in regulating the cascade predisposes to accelerated organ failure, as observed in colitis and transplant rejection. Given that there are over 60 proteins in this system, it has become an attractive target for immunotherapeutics, many of which are United States Food and Drug Administration-approved or in multiple phase 2/3 clinical trials. Moreover, there have been key advances in the last few years in the understanding of how the complement system operates locally in tissues, independent of its activities in circulation. In this review, we will put into perspective the abovementioned discoveries to optimally modulate the spatiotemporal nature of complement activation and regulation at mucosal surfaces.

Tanreqing Injection Inhibits Activation of NLRP3 Inflammasome in Macrophages Infected with Influenza A Virus by Promoting Mitophagy.

OBJECTIVE: To investigate the inhibitory effect of Tanreqing Injection (TRQ) on the activation of nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 (NLRP3) inflammasome in macrophages infected with influenza A virus and the underlying mechanism based on mitophagy pathway. METHODS: The inflammatory model of murine macrophage J774A.1 induced by influenza A virus [strain A/Puerto Rico/8/1934 (H1N1), PR8] was constructed and treated by TRQ, while the mitochondria-targeted antioxidant Mito-TEMPO and autophagy specific inhibitor 3-methyladenine (3-MA) were used as controls to intensively study the anti-inflammatory mechanism of TRQ based on mitophagy-mitochondrial reactive oxygen species (mtROS)-NLRP3 inflammasome pathway. The levels of NLRP3, Caspase-1 p20, microtubule-associated protein 1 light chain 3 II (LC3II) and P62 proteins were measured by Western blot. The release of interleukin-1ß (IL-1ß) was tested by enzyme linked immunosorbent assay, the mtROS level was detected by flow cytometry, and the immunofluorescence and co-localization of LC3 and mitochondria were observed under confocal laser scanning microscopy. RESULTS: Similar to the effect of Mito-TEMPO and contrary to the results of 3-MA treatment, TRQ could significantly reduce the expressions of NLRP3, Caspase-1 p20, and autophagy adaptor P62, promote the expression of autophagy marker LC3II, enhance the mitochondrial fluorescence intensity, and inhibit the release of mtROS and IL-1ß (all P<0.01). Moreover, LC3 was co-localized with mitochondria, confirming the type of mitophagy. CONCLUSION: TRQ could reduce the level of mtROS by promoting mitophagy in macrophages infected with influenza A virus, thus inhibiting the activation of NLRP3 inflammasome and the release of IL-1ß, and attenuating the inflammatory response.

Circulating perturbation of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) is associated to cardiac remodeling and NLRP3 inflammasome in cardiovascular patients with insulin resistance risk.

Lipidome perturbation occurring during meta-inflammation is associated to left ventricle (LV) remodeling though the activation of the NLRP3 inflammasome, a key regulator of chronic inflammation in obesity-related disorders. Little is known about phosphatidylcholine (PC) and phosphatidylethanolamine (PE) as DAMP-induced NLRP3 inflammasome. Our study is aimed to evaluate if a systemic reduction of PC/PE molar ratio can affect NLRP3 plasma levels in cardiovascular disease (CVD) patients with insulin resistance (IR) risk. Forty patients from IRCCS Policlinico San Donato were enrolled, and their blood samples were drawn before heart surgery. LV geometry measurements were evaluated by echocardiography and clinical data associated to IR risk were collected. PC and PE were quantified by ESI-MS/MS. Circulating NLRP3 was quantified by an ELISA assay. Our results have shown that CVD patients with IR risk presented systemic lipid impairment of PC and PE species and their ratio in plasma was inversely associated to NLRP3 levels. Interestingly, CVD patients with IR risk presented LV changes directly associated to increased levels of NLRP3 and a decrease in PC/PE ratio in plasma, highlighting the systemic effect of meta-inflammation in cardiac response. In summary, PC and PE can be considered bioactive mediators associated to both the NLRP3 and LV changes in CVD patients with IR risk.

Nlrp6 protects from corticosterone-induced NSPC ferroptosis by modulating RIG-1/MAVS-mediated mitophagy.

Hippocampal neural stem/progenitor cells (NSPCs) are highly vulnerable to different stress stimuli, resulting in adult neurogenesis decline and eventual cognitive defects. Our previous study demonstrated that NOD-like receptor family pyrin domain-containing 6 (Nlrp6) highly expressed in NSPCs played a critical role in sustaining hippocampal neurogenesis to resist stress-induced depression, but the underlying mechnistms are still unclear. Here, we found that Nlrp6 depletion led to cognitive defects and hippocampal NSPC loss in mice. RNA-sequencing analysis of the primary NSPCs revealed that Nlrp6 deficiency altered gene expression profiles of mitochondrial energy generation and ferroptotic process. Upon siNlrp6 transfection, as well as corticosterone (CORT) exposure, downregulation of Nlrp6 suppressed retinoic acid-inducible gene I (RIG-1)/mitochondrial antiviral signaling proteins (MAVS)-mediated autophagy, but drove NSPC ferroptotic death. More interesting, short chain fatty acids (SCFAs) upregulated Nlrp6 expression and promoted RIG-1/MAVS-mediated mitophagy, preventing CORT-induced NSPC ferroptosis. Our study further demonstrates that Nlrp6 should be a sensor for RIG-1/MAVS-mediated mitophagy and play a critical role in maintain mitochondrial homeostasis of hippocampal NSPCs. These results suggests that Nlrp6 should be a potential drug target to combat neurodegenerative diseases relative with chronic stress.

Evaluation of inflammasomes as biomarker following non-surgical periodontal treatment.

OBJECTIVE: The purpose of this study was to investigate interleukin (IL)-1ß, IL-18, nod-like receptor pyrin domain-containing protein 3 (NLRP3), apoptosis-related speck-like protein containing a caspase activation and recruitment domain (ASC), and caspase-1 levels in saliva and serum in different periodontal diseases and to evaluate the changes after non-surgical periodontal treatment (NSPT). DESIGN: A total of 45 participants, 15 healthy, 15 gingivitis, and 15 stage III grade C (SIIIGC) periodontitis patients, were included in the study. Periodontal parameters were assessed, and salivary and serum samples were collected at baseline in all groups and one and three months after NSPT in gingivitis and periodontitis groups. An enzyme-linked immunosorbent assay was used to analyse IL-1ß, IL-18, NLRP3, ASC, and caspase-1 levels. RESULTS: After NSPT, improvement was observed in all clinical parameters, along with periodontal inflamed surface area (PISA) in gingivitis and periodontitis groups. PISA scores were positively correlated with IL-1ß, NLRP3, and caspase-1 at baseline (p < 0.05). Salivary and serum IL-1ß, NLRP3 levels were higher in periodontitis compared to healthy controls at baseline and reduced after treatment (p < 0.05). Receiver operating characteristic analysis revealed that salivary IL-1ß, NLRP3, and caspase-1 had the ability to discriminate SIIIGC periodontitis patients from healthy subjects (p < 0.05). CONCLUSION: In conclusion, salivary IL-1ß, NLRP3, and caspase-1 are at aberrantly high levels in SIIIGC periodontitis and are remarkably decreased following NSPT; these inflammasome biomarkers may show potential utility in diagnosing and monitoring periodontitis.

Jianpi Gushen Huayu decoction ameliorated diabetic nephropathy through modulating metabolites in kidney, and inhibiting TLR4/NF-κB/NLRP3 and JNK/P38 pathways.

BACKGROUND: Jianpi Gushen Huayu Decoction (JPGS) has been used to clinically treat diabetic nephropathy (DN) for many years. However, the protective mechanism of JPGS in treating DN remains unclear. AIM: To evaluate the therapeutic effects and the possible mechanism of JPGS on DN. METHODS: We first evaluated the therapeutic potential of JPGS on a DN mouse model. We then investigated the effect of JPGS on the renal metabolite levels of DN mice using non-targeted metabolomics. Furthermore, we examined the effects of JPGS on c-Jun N-terminal kinase (JNK)/P38-mediated apoptosis and the inflammatory responses mediated by toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/NOD-like receptor family pyrin domain containing 3 (NLRP3). RESULTS: The ameliorative effects of JPGS on DN mice included the alleviation of renal injury and the control of inflammation and oxidative stress. Untargeted metabolomic analysis revealed that JPGS altered the metabolites of the kidneys in DN mice. A total of 51 differential metabolites were screened. Pathway analysis results indicated that nine pathways significantly changed between the control and model groups, while six pathways significantly altered between the model and JPGS groups. Pathways related to cysteine and methionine metabolism; alanine, tryptophan metabolism; aspartate and glutamate metabolism; and riboflavin metabolism were identified as the key pathways through which JPGS affects DN. Further experimental validation showed that JPGS treatment reduced the expression of TLR4/NF-κB/NLRP3 pathways and JNK/P38 pathway-mediated apoptosis related factors. CONCLUSION: JPGS could markedly treat mice with streptozotocin (STZ)-induced DN, which is possibly related to the regulation of several metabolic pathways found in kidneys. Furthermore, JPGS could improve kidney inflammatory responses and ameliorate kidney injuries in DN mice via the TLR4/NF-κB/NLRP3 pathway and inhibit JNK/P38 pathway-mediated apoptosis in DN mice.

Heterozygous Pyrin (MEFV) E148Q allele carriers indicate a reduced glaucoma risk for Turkish population: a prospective clinical analysis.

PURPOSE: The MEFV gene encodes pyrin, a protein linked to increased severity of symptoms in Familial Mediterranean Fever (FMF). We consider that inflammation due to MEFV variants would increase eye inflammation and damage aqueous humor regulation. The present study is the first analysis investigating a MEFV (E148Q) variant as a marker protecting from glaucoma. METHODS: In this prospective clinical analyze, we performed detailed gene sequencing focusing on 22 specific regions of the pyrin (MEFV) gene. The study involved two distinct groups: individuals diagnosed with glaucoma (n = 200) and control subjects without glaucoma (n = 100). Both groups were carefully selected to exclude individuals with symptoms or a previous diagnosis of Familial Mediterranean Fever (FMF). The diagnosis of glaucoma for each participant was rigorously established through comprehensive direct ophthalmic examinations. RESULTS: A significant odds ratio for protection against glaucoma was found in carriers of the subclinical E148Q allele (OR:2.22; 95%CI: 1.098-4.485). No significant differences were found for other variants. One mutant E148Q-allele could decrease the probability of glaucoma development by approximately 68,9%. We observed no differences in the genotype frequency between glaucoma and healthy for the other MEFV gene variants. CONCLUSION: The pyrin variant of the MEFV gene resulting in a subclinical phenotype appears to reduce the incidence of glaucoma, and heterozygous pyrin (MEFV) E148Q allele carriers confer protection against glaucoma. It is important to consider the limitations arising from the relatively small number of studies conducted on this topic.

Clustering human dental pulp fibroblasts spontaneously activate NLRP3 and AIM2 inflammasomes and induce IL-1ß secretion.

Objectives: The objective of the present study was to investigate whether NOD-like receptor family pyrin domain-containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasomes pathways were involved in an experimental model of fibroblast activation named nemosis, which was used to mimic circumstances without bacteria stimulation. Methods: Nemosis of human dental pulp fibroblast (DPFs) was induced by three-dimensional culture in U-shaped 96-well plates and investigated by scanning electron microscopy (SEM). DPFs monolayers were used as control. Annexin V-FITC/7-AAD apoptosis assay was performed on the DPFs spheroids by flowcytometry. Caspase-1 activity detection assay was conducted on the DPFs spheroids. Quantitative real-time polymerase chain reaction (qRT-PCR), cytokine measurements, Western blot and the effect of COX-2 inhibitor on spheroids was studied. Results: SEM study observed human dental pulp fibroblast clusters and cell membranes damage on the surface of DPFs spheroids. The percentages of necrotic cells from DPFs spheroids gradually increased as the incubation time increased. A statistically significant increase in caspase-1 activity was observed after DPFs spheroids formation. DPFs spheroids displayed significant amounts of NLRP3, AIM2 mRNA and protein expression, caspase-1 mRNA expression and cleaved Caspase-1 protein expression and high IL-1ß concentrations (P < 0.05) than DPFs monolayers. Specific COX-2 inhibitor (NS-398) decreased NLRP3 mRNA and protein expression, cleaved Caspase-1 protein expression, Caspase-1 activity and IL-1ß mRNA expression and IL-1ß concentrations (P < 0.05). However, Specific COX-2 inhibitor had no impact on AIM2 mRNA and protein expression, caspase-1 mRNA expression and pro-Caspase-1 protein expression. Conclusions: In conclusion, clustering human DPFs spontaneously activated NLRP3 and AIM2 inflammasomes and induced IL-1ß secretion which could be partially attenuated by COX-2 inhibitor. Thus, nemosis could become a powerful model for studying mechanisms underlying aseptic pulpitis.

Vitamin D Mitigates Hepatic Fat Accumulation and Inflammation and Increases SIRT1/AMPK Expression in AML-12 Hepatocytes.

Emerging evidence has demonstrated a strong correlation between vitamin D status and fatty liver disease. Aberrant hepatic fat infiltration contributes to oxidant overproduction, promoting metabolic dysfunction, and inflammatory responses. Vitamin D supplementation might be a good strategy for reducing hepatic lipid accumulation and inflammation in non-alcoholic fatty liver disease and its associated diseases. This study aimed to investigate the role of the most biologically active form of vitamin D, 1,25-dihydroxyvitamin D (1,25(OH)2D), in hepatic fat accumulation and inflammation in palmitic acid (PA)-treated AML-12 hepatocytes. The results indicated that treatment with 1,25(OH)2D significantly decreased triglyceride contents, lipid peroxidation, and cellular damage. In addition, mRNA levels of apoptosis-associated speck-like CARD-domain protein (ASC), thioredoxin-interacting protein (TXNIP), NOD-like receptor family pyrin domain-containing 3 (NLRP3), and interleukin-1ß (IL-1ß) involved in the NLRP3 inflammasome accompanied by caspase-1 activity and IL-1ß expression were significantly suppressed by 1,25(OH)2D in PA-treated hepatocytes. Moreover, upon PA exposure, 1,25(OH)2D-incubated AML-12 hepatocytes showed higher sirtulin 1 (SIRT1) expression and adenosine monophosphate-activated protein kinase (AMPK) phosphorylation. A SIRT1 inhibitor alleviated the beneficial effects of 1,25(OH)2D on PA-induced hepatic fat deposition, IL-1ß expression, and caspase-1 activity. These results suggest that the favorable effects of 1,25(OH)2D on hepatic fat accumulation and inflammation may be, at least in part, associated with the SIRT1.

Yemazhui () ameliorates lipopolysaccharide-induced acute lung injury modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flora in rats.

OBJECTIVE: To investigate the impact of Yemazhui (Herba Eupatorii Lindleyani, HEL) against lipopolysaccharide (LPS)-induced acute lung injury (ALI) and explore its underlying mechanism in vivo. METHODS: The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry method. Then, HEL was found to suppress LPS-induced ALI in vivo. Six-week-old male Sprague-Dawley rats were randomly divided into 6 groups: control, LPS, Dexamethasone (Dex), HEL low dose 6 g/kg (HEL-L), HEL medium dose 18 g/kg (HEL-M) and HEL high dose 54 g/kg (HEL-H) groups. The model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI model. Leukocyte counts, lung wet/dry weight ratio, as well as myeloperoxidase (MPO) activity were determined followed by the detection with hematoxylin and eosin staining, enzyme linked immunosorbent assay, quantitative real time polymerase chain reaction, western blotting, immunohistochemistry, and immunofluorescence. Besides, to explore the effect of HEL on ALI-mediated intestinal flora, we performed 16s rRNA sequencing analysis of intestinal contents. RESULTS: HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora disturbance. Mechanism study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats, inhibited leukocytes exudation and MPO activity, and improved the pathological injury of lung tissue. In addition, HEL reduced the expression of tumor necrosis factor-alpha, interleukin-1beta (IL-1ß) and interleukin-6 (IL-6) in bronchoalveolar lavage fluid and serum, and inhibited nuclear displacement of nuclear factor kappa-B p65 (NF-κBp65). And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4 (TLR4), myeloid differentiation factor 88, NF-κBp65, phosphorylated inhibitor kappa B alpha (phospho-IκBα), nod-like receptor family pyrin domain-containing 3 protein (NLRP3), IL-1ß, and interleukin-18 (IL-18) in lung tissue, and regulated intestinal flora disturbance. CONCLUSIONS: In summary, our findings revealed that HEL has a protective effect on LPS-induced ALI in rats, and its mechanism may be related to inhibiting TLR4/ NF-κB/NLRP3 signaling pathway and improving intestinal flora disturbance.

Gegen Qinlian decoction ameliorates TNBS-induced ulcerative colitis by regulating Th2/Th1 and Tregs/Th17 cells balance, inhibiting NLRP3 inflammasome activation and reshaping gut microbiota.

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herbal medicine Gegen Qinlian Decoction (GQD) has been clinically shown to be an effective treatment of ulcerative colitis (UC) in China. However, the underlying mechanism of GQD's anti-ulcerative colitis properties and its effect on gut microbiota still deserve further exploration. AIM OF THE STUDY: This study observed the regulatory effects of GQD on Th2/Th1 and Tregs/Th17 cells balance, the NOD-like receptor family pyrin domain containing 3 (NLRP3) infammasome and gut microbiota in TNBS-induced UC in BALB/c mice. MATERIALS AND METHODS: 61 main chemical compounds in the GQD were determined by UPLC-Q-TOF/MS. The UC BALB/c model was established by intrarectal administration of trinitrobenzene sulfonic acid (TNBS), and GQD was orally administered at low and high dosages of 2.96 and 11.83 g/kg/day, respectively. The anti-inflammatory effects of GQD for ulcerative colitis were evaluated by survival rate, body weight, disease activity index (DAI) score, colonic weight and index, spleen index, hematoxylin-eosin (HE) staining and histopathological scores. Flow cytometry was used to detect the percentage of CD4, Th1, Th2, Th17 and Tregs cells. The levels of Th1-/Th2-/Th17-/Tregs-related inflammatory cytokines and additional proinflammatory cytokines (IL-1ß, IL-18) were detected by CBA, ELISA, and RT-PCR. The expressions of GATA3, T-bet, NLRP3, Caspase-1, IL-Iß, Occludin and Zonula occludens-1 (ZO-1) on colon tissues were detected by Western blot and RT-PCR. Transcriptome sequencing was performed using colon tissue and 16S rRNA gene sequencing was performed on intestinal contents. Fecal microbiota transplantation (FMT) was employed to assess the contribution of intestinal microbiota and its correlation with CD4 T cells and the NLRP3 inflammasome. RESULTS: GQD increased the survival rate of TNBS-induced UC in BALB/c mice, and significantly improved their body weight, DAI score, colonic weight and index, spleen index, and histological characteristics. The intestinal barrier dysfunction was repaired after GQD administration through promoting the expression of tight junction proteins (Occludin and ZO-1). GQD restored the balance of Th2/Th1 and Tregs/Th17 cells immune response of colitis mice, primarily inhibiting the increase in Th2/Th1 ratio and their transcription factor production (GATA3 and T-bet). Morever, GQD changed the secretion of Th1-/Th2-/Th17-/Tregs-related cytokines (IL-2, IL-12, IL-5, IL-13, IL-6, IL-10, and IL-17A) and reduced the expressions of IL-1ß, IL-18. Transcriptome results suggested that GQD could also remodel the immune inflammatory response of colitis by inhibiting NOD-like receptor signaling pathway, and Western blot, immunohistochemistry and RT-PCR further revealed that GQD exerted anti-inflammatory effects by inhibiting the NLRP3 inflammasome, such as down-regulating the expression of NLRP3, Caspase-1 and IL-1ß. More interestingly, GQD regulated gut microbiota dysbiosis, suppressed the overgrowth of conditional pathogenic gut bacteria like Helicobacter, Proteobacteria, and Mucispirillum, while the probiotic gut microbiota, such as Lactobacillus, Muribaculaceae, Ruminiclostridium_6, Akkermansia, and Ruminococcaceae_unclassified were increased. We further confirmed that GQD-treated gut microbiota was sufficient to relieve TNBS-induced colitis by FMT, involving the modulation of Th2/Th1 and Tregs/Th17 balance, inhibition of NLRP3 inflammasome activation, and enhancement of colonic barrier function. CONCLUSIONS: GQD might alleviate TNBS-induced UC via regulating Th2/Th1 and Tregs/Th17 cells Balance, inhibiting NLRP3 inflammasome and reshaping gut microbiota, which may provide a novel strategy for patients with colitis.

LanGui tea, an herbal medicine formula, protects against binge alcohol-induced acute liver injury by activating AMPK-NLRP3 signaling.

BACKGROUND: LanGui tea, a traditional Chinese medicine formulation comprising of Gynostemma pentaphyllum (Thunb.) Makino, Cinnamomum cassia (L.) J. Presl, and Ampelopsis grossedentata (Hand-Mazz) W.T. Wang, has yet to have its potential contributions to alcoholic liver disease (ALD) fully elucidated. Consequently, the objective of this research is to investigate the protective properties of LanGui tea against binge alcohol-induced ALD and the mechanisms underlying its effects. METHODS: An experimental model of acute alcohol-induced liver disease was performed to assess the protective effects of extract of LanGui tea (ELG) at both 50 and 100 mg.kg-1 dosages on male C57BL/6 mice. Various parameters, including hepatic histological changes, inflammation, lipids content, as well as liver enzymes and interleukin 1ß (IL-1ß) in the serum were measured. The pharmacological mechanisms of ELG, specifically its effects on adenosine monophosphate-(AMP)-activated protein kinase (AMPK) and NLR family pyrin domain containing 3 (NLRP3) signaling, were investigated through Western blotting, qRT-PCR, ELISA, immunohistochemistry, immunofluorescence analyses, and by blocking the AMPK activity. RESULTS: ELG demonstrated a mitigating effect on fatty liver, inflammation, and hepatic dysfunction within the mouse model. This effect was achieved by activating AMPK signaling and inhibitingNLRP3 signaling in the liver, causing a reduction in IL-1ß generation. In vitro studies further confirmed that ELG inhibited cell damage and IL-1ß production in ethanol-induced hepatocytes by enhancing AMPK-NLRP3 signaling. Conversely, the pharmacological inhibition of AMPK activity nearly abrogated such alteration. CONCLUSIONS: Thus, LanGui tea emerges as a promising herbal therapy for ALD management involving AMPK-NLRP3 signaling.

Helicobacter pylori secretary Proteins-Induced oxidative stress and its role in NLRP3 inflammasome activation.

Helicobacter pylori-associated stomach infection is a leading cause of gastric ulcer and related cancer. H. pylori modulates the functions of infiltrated immune cells to survive the killing by reactive oxygen and nitrogen species (ROS and RNS) produced by these cells. Uncontrolled immune responses further produce excess ROS and RNS which lead to mucosal damage. The persistent oxidative stress is a major cause of gastric cancer. H. pylori regulates nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs), nitric oxide synthase 2 (NOS2), and polyamines to control ROS and RNS release through lesser-known mechanisms. ROS and RNS produced by these pathways differentiate macrophages and T cells from protective to inflammatory phenotype. Pathogens-associated molecular patterns (PAMPs) induced ROS activates nuclear oligomerization domain (NOD), leucine rich repeats (LRR) and pyrin domain-containing protein 3 (NLRP3) inflammasome for the release of pro-inflammatory cytokines. This study evaluates the role of H. pylori secreted concentrated proteins (HPSCP) related oxidative stress role in NLRP3 inflammasome activation and macrophage differentiation. To perceive the role of ROS/RNS, THP-1 and AGS cells were treated with 10 µM diphenyleneiodonium (DPI), 50 µM salicyl hydroxamic acid (SHX), 5 µM Carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone (FCCP), which are specific inhibitors of NADPH oxidase (NOX), Myeloperoxidase (MPO), and mitochondrial oxidative phosphorylation respectively. Cells were also treated with 10 µM of NOS2 inhibitor l-NMMA and 10 µM of N-acetyl cysteine (NAC), a free radical scavenger·H2O2 (100 µM) treated and untreated cells were used as positive controls and negative control respectively. The expression of gp91phox (NOX2), NOS2, NLRP3, CD86 and CD163 was analyzed through fluorescent microscopy. THP-1 macrophages growth was unaffected whereas the gastric epithelial AGS cells proliferated in response to higher concentration of HPSCP. ROS and myeloperoxidase (MPO) level increased in THP-1 cells and nitric oxide (NO) and lipid peroxidation significantly decreased in AGS cells. gp91phox expression was unchanged, whereas NOS2 and NLRP3 downregulated in response to HPSCP, but increased after inhibition of NO, ROS and MPO in THP-1 cells. HPSCP upregulated the expression of M1 and M2 macrophage markers, CD86 and CD163 respectively, which was decreased after the inhibition of ROS. This study concludes that there are multiple pathways which are generating ROS during H. pylori infection which further regulates other cellular processes. NO is closely associated with MPO and inhibition of NLRP3 inflammasome. The low levels of NO and MPO regulates gastrointestinal tract homeostasis and overcomes the inflammatory response of NLRP3. The ROS also plays crucial role in macrophage polarization hence alter the immune responses duing H. pylori pathogenesis.

A stress sensor, IRE1α, is required for bacterial-exotoxin-induced interleukin-1ß production in tissue-resident macrophages.

Cholera toxin (CT), a bacterial exotoxin composed of one A subunit (CTA) and five B subunits (CTB), functions as an immune adjuvant. CTB can induce production of interleukin-1ß (IL-1ß), a proinflammatory cytokine, in synergy with a lipopolysaccharide (LPS), from resident peritoneal macrophages (RPMs) through the pyrin and NLRP3 inflammasomes. However, how CTB or CT activates these inflammasomes in the macrophages has been unclear. Here, we clarify the roles of inositol-requiring enzyme 1 alpha (IRE1α), an endoplasmic reticulum (ER) stress sensor, in CT-induced IL-1ß production in RPMs. In RPMs, CTB is incorporated into the ER and induces ER stress responses, depending on GM1, a cell membrane ganglioside. IRE1α-deficient RPMs show a significant impairment of CT- or CTB-induced IL-1ß production, indicating that IRE1α is required for CT- or CTB-induced IL-1ß production in RPMs. This study demonstrates the critical roles of IRE1α in activation of both NLRP3 and pyrin inflammasomes in tissue-resident macrophages.

Bif­1 inhibits activation of inflammasome through autophagy regulatory mechanism.

Inflammasome activation is a crucial mechanism in inflammatory responses. Bax­interacting factor 1 (Bif­1) is required for the normal formation of autophagosomes, but its ability to exert an inflammatory regulatory effect remains unclear. The aim of the present study was to explore the role of Bif­1 in inflammation, possibly mediated through autophagy regulation. Using a lipopolysaccharide (LPS)/adenosine triphosphate (ATP)­induced inflammatory model in J774A.1 cells, the effect of Bif­1 on inflammasome activation and the underlying mechanisms involving autophagy regulation were investigated. Elevated levels of NLR family pyrin domain containing protein 3 inflammasome and interleukin­1ß (IL­1ß) proteins were observed in J774A.1 cells after LPS/ATP induction. Furthermore, Bif­1 and autophagy activity were significantly upregulated in inflammatory cells. Inhibition of autophagy resulted in inflammasome activation. Silencing Bif­1 expression significantly upregulated IL­1ß levels and inhibited autophagy activity, suggesting a potential anti­inflammatory role of Bif­1 mediated by autophagy. Additionally, inhibition of the nuclear factor­κB (NF­κB) signaling pathway downregulated Bif­1 and inhibited autophagy activity, highlighting the importance of NF­κB in the regulation of Bif­1 and autophagy. In summary, the current study revealed that Bif­1 is a critical anti­inflammatory factor against inflammasome activation mediated by a mechanism of autophagy regulation, indicating its potential as a therapeutic target for inflammatory regulation.

Expression and correlation of the NOD-like receptor family, pyrin domain-containing 3 inflammasome and the silent information regulator 1 in patients with drug-resistant epilepsy.

BACKGROUND: The NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammatory pathway is implicated in the development of epilepsy and can be suppressed by the activation of the silent information regulator 1 (SIRT1). However, the expression and correlation of the NLRP3 pathway and SIRT1 in drug-resistant epilepsy (DRE) remain unknown. METHODS: This study evaluated the histopathology of the cerebral cortex from nine patients with DRE and eight patients with cavernous haemangioma undergoing surgical treatment. It analysed the expression of the NLRP3, interleukin-1ß (IL-1ß), caspase-1 and SIRT1 using immunohistochemistry. Additionally, the contents of NLRP3, caspase-1, IL-1ß and SIRT1 in the serum samples of the included study participants were determined using ELISA method. The correlation between the NLRP3 pathway and the SIRT1 was assessed using Spearman's correlation analysis. RESULTS: The expression of NLRP3, caspase-1 and IL-1ß in the cerebral cortex of patients with DRE was elevated, with the NLRP3 expression being negatively correlated with the SIRT1 expression. Furthermore, IL-1ß in serum was upregulated in patients with DRE. The correlation between the content of serum SIRT1 and NLRP3, caspase-1 and IL-1ß in patients with DRE was not significant. Notably, serum caspase-1 levels were obviously higher in patients with bilateral hippocampal sclerosis than in patients with unilateral hippocampal sclerosis. CONCLUSIONS: The current results indicate that the expression of the NLRP3/caspase-1/IL-1ß pathway is significantly upregulated in patients with DRE and that it is partially correlated with the SIRT1 expression. This study is important for understanding the pathophysiology of DRE and developing new treatment strategies for it.

Americanin B inhibits pyroptosis in lipopolysaccharide-induced septic encephalopathy mice through targeting NLRP3 protein.

BACKGROUND: Sepsis is considered as a severe illness due to its high mortality. Sepsis can cause septic encephalopathy, thus leading to brain injury, behavioral and cognitive dysfunction. Pyroptosis is a type of regulated cell death (RCD) and takes a crucial part in occurrence and development of sepsis. Americanin B (AMEB) is a lignan compounds, which is extracted from Vernicia fordii. In our previous study, AMEB could inhibit microglial activation in inflammatory cell model. However, the function of AMEB in septic encephalopathy mice is uncertain. It would be worthwhile to ascertain the role and mechanism of AMEB in sepsis. PURPOSE: Current study designs to certify the relationship between pyroptosis and septic encephalopathy, and investigate whether AMEB can restrain NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation and restrict pyroptosis by targeting NLRP3 in septic mice model. STUDY DESIGN: C57BL/6 mice were utilized to perform sepsis model in vivo experiments. BV-2 cell lines were used for in vitro experiments. METHODS: In vivo sepsis model was established by lipopolysaccharide (LPS) intraperitoneal injection in male C57BL/6 J mice and in vitro model was exposed by LPS plus ATP in BV-2 cells. The survival rate was monitored on the corresponding days. NLRP3, apoptosis associated Speck-like protein (ASC), caspase-1, GasderminD (GSDMD), interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) level were detected by western blotting and immunofluorescence analysis. Molecular docking, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) experiments, RNAi transfection and quantitative real-time PCR were applied to confirm the potential target of AMEB. RESULTS: The results suggested that AMEB could rise survival percentage and lighten brain injury in LPS-induced sepsis mice. In addition, AMEB could inhibit pyroptosis and the activiation of NLRP3 inflammasome. The inhibiting function of AMEB on the activiation of NLRP3 inflammasome is weakened following si-NLRP3 transfection. Moreover, AMEB exerted anti-pyroptosis effect via targeting NLRP3 protein. CONCLUSIONS: Our findings first indicate NLRP3 is an effective druggable target for septic encephalopathy related brain injury, and also provide a candidate-AMEB for the treatment of septic encephalopathy. These emerging findings on AMEB in models of sepsis suggest an innovative approach that may be beneficial in the prevention of septic encephalopathy.

NLRP3 deficiency protects against acetaminophen­induced liver injury by inhibiting hepatocyte pyroptosis.

Acetaminophen (APAP) overdose is the primary cause of drug­induced acute liver failure in numerous Western countries. NLR family pyrin domain containing 3 (NLRP3) inflammasome activation serves a pivotal role in the pathogenesis of various forms of acute liver injury. However, the cellular source for NLRP3 induction and its involvement during APAP­induced hepatotoxicity have not been thoroughly investigated. In the present study, hematoxylin and eosin staining was performed to assess histopathological changes of liver tissue. Immunohistochemistry staining(NLRP3, Caspase­1, IL­1ß, GSDMD and Caspase­3), western blotting (NLRP3, Caspase­1, IL­1ß, GSDMD and Caspase­3) and RT­qPCR (NLRP3, Caspase­1 and IL­1ß) were performed to assess the expression of NLRP3/GSDMD signaling pathway. TUNEL staining was performed to assess apoptosis of liver tissue. The serum expression levels of inflammatory factors (IL­6, IL­18, IL­1ß and TNF­α) were assessed using ELISA and inflammation of liver tissue was assessed using immunohistochemistry (Ly6G and CD68) and RT­qPCR (TNF­α, Il­6, Mcp­1, Cxcl­1, Cxcl­2). A Cell Counting Kit­8 was performed to assess cell viability and apoptosis. Protein and gene expression were analyzed by western blotting (PCNA, CCND1) and RT­qPCR (CyclinA2, CyclinD1 and CyclinE1). Through investigation of an APAP­induced acute liver injury model (AILI), the present study demonstrated that APAP overdose induced activation of NLRP3 and cleavage of gasdermin D (GSDMD) in hepatocytes, both in vivo and in vitro. Additionally, mice with hepatocyte­specific knockout of Nlrp3 exhibited reduced liver injury and lower mortality following APAP intervention, accompanied by decreased infiltration of inflammatory cells and attenuated inflammatory response. Furthermore, pharmacological blockade of NLRP3/GSDMD signaling using MCC950 or disulfiram significantly ameliorated liver injury and reduced hepatocyte death. Notably, hepatocyte Nlrp3 deficiency promoted liver recovery by enhancing hepatocyte proliferation. Collectively, the present study demonstrated that inhibition of the NLRP3 inflammasome protects against APAP­induced acute liver injury by reducing hepatocyte pyroptosis and suggests that targeting NLRP3 may hold therapeutic potential for treating AILI.