Thiolutin attenuates ischemic stroke injury via inhibition of NLRP3 inflammasome: an in vitro and in vivo study

Thiolutin, a novel NLRP3 inflammasome inhibitor, mitigates IgA nephropathy in mice

NLRP3 inflammasome plays a key role in IgA Nephropathy (IgAN) pathogenesis. Thiolutin (THL) is an NLRP3 inflammasome inhibitor with anti-inflammatory effects, but its role in IgAN is unclear. This study aimed to evaluate the protective efficacy of THL in IgAN mice, alongside assessing its inhibitory mechanisms. IgAN was induced by administration of bovine serum albumin combined with Staphylococcal Enterotoxin B in mice, followed by THL treatment. Kidney injury biomarkers, inflammatory cytokines, histological changes and the NLRP3 inflammasome pathway were assessed. The effect of THL on pyroptosis and action site on inflammasome was examined in J774A.1 cells, and co-immunoprecipitation was used to study specific protein interactions. In IgAN mice, THL treatment significantly reduced renal dysfunctional markers and histological injury without affecting hepatic function, accompanied by decreased serum IgA levels, renal IgA deposition and pro-inflammatory cytokine accumulation via regulating the mRNA and protein expression of key inflammasome components. It also attenuated pyroptosis and NLRP3 inflammasome activation instead of priming in macrophages, via disturbing the combination of NLRP3 with apoptosis-associated speck-like protein and NIMA-Related Kinase 7. THL has significant anti-inflammatory and renal protective effects in IgAN via inhibiting the NLRP3 inflammasome pathway. Its selective impact on the activation and assembly of the inflammasome, without affecting priming, highlights its potential as a targeted therapeutic agent in IgAN management.

Untargeted metabolomics unveils critical metabolic signatures in novel phenotypes of acute ischemic stroke

This study aimed to identify metabolic footprints associated with distinct phenotypes of acute ischemic stroke (AIS) using untargeted metabolomics. We included 20 samples each from AIS phenotype A (n = 251), B (n = 213), and C (n = 43) groups, along with 20 age- and gender-matched healthy controls (HCs). Plasma metabolic profiles were analyzed using liquid chromatography-mass spectrometry (LC-MS). Weighted gene correlation network analysis (WGCNA) evaluated associations between metabolite clusters and clinical traits, including the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). We identified three, five, and six key differential metabolites for diagnosing phenotypes A, B, and C, respectively, demonstrating high diagnostic performance. These metabolites were focused on fatty acids, sex hormones, amino acids, and their derivatives. WGCNA identified 12 core metabolites involved in phenotype progression. Notably, phenylalanylphenylalanine and phenylalanylleucine were inversely correlated with disease severity and disability. Metabolites related to energy supply and inflammation were common across phenotypes, with additional changes in ionic homeostasis in phenotype A and decreased neurotransmitter release in phenotype C. Biosynthesis of unsaturated fatty acids and the pentose phosphate pathway (PPP) were relevant across all phenotypes, while the folate biosynthesis pathway was linked to phenotype C and clinical scales. Key metabolites, including phenylalanylphenylalanine and phenylalanylleucine, and pathways such as folate biosynthesis, significantly contribute to AIS severity and differentiation of phenotypes. These findings offer new insights into the pathogenesis and mechanisms underlying AIS phenotypes.

Thiolutin Alleviates Cardiotoxic Effects of Doxorubicin by Suppressing NLRP3 Inflammasome in the Mouse Model

Doxorubicin (DOX) has a limitation in clinical oncology due to its dose-dependent cardiotoxicity. Thiolutin (THL) can undermine DOX-induced cardiomyocyte injury by inhibiting the NLRP3 inflammasome activation, yet the efficacy of THL in DOX-induced cardiotoxicity (DOXIC) needs to be validated in animal models. DOX-induced mice were treated with THL to evaluate the efficacy of THL. Relative NLRP3 mRNA levels were determined by quantitative PCR. Blood samples were collected from diffuse large B-cell lymphoma (DLBCL) patients with or without DOXIC to validate serum levels of cTnT, IL-1β, CRP, BNP, and IL-18 by enzyme-linked immunosorbent assay. Apoptosis and pyroptosis-related protein levels were analyzed by western blot. Cardiac function and histopathological changes were determined by echocardiography, HE, Masson's, and wheat germ agglutinin staining. In clinical samples, NLRP3 mRNA and/or protein levels were also markedly heightened in peripheral blood mononuclear cells and serum samples from DOXIC patients, along with higher concentrations of IL-18, cTnT, and IL-1β. Importantly, cTnT possessed a positive correlation with NLRP3 mRNA, IL-1β, and IL-18. Moreover, cTnT possessed a positive correlation with NLRP3 mRNA, IL-1β, and IL-18 levels, suggesting a potential link between DOXIC and NLRP3 inflammasome. The outcomes demonstrated that THL reduced LVEF and LVFS, as well as elevated LVESD and LVEDD in DOX-challenged mice, accompanied by elevated serum concentrations of cTnT, CRP, and BNP. In addition, THL attenuated DOX-induced myocardial hypertrophy and cardiac fibrosis in mice, in conjunction with attenuation of DOX-induced upregulation of C-caspase3, Bax, NLRP3, C-caspase-1/Pro-caspase, GSDMD-N/GSDMD, IL-1β, and IL-18 in heart or serum samples. In conclusion, our data supported that THL alleviates the cardiotoxic effects of DOX and suppresses NLRP3 inflammasome in the mouse model, suggesting that THL as a potential drug for DOXIC.

Pyroptosis in health and disease: mechanisms, regulation and clinical perspective

Pyroptosis is a type of programmed cell death characterized by cell swelling and osmotic lysis, resulting in cytomembrane rupture and release of immunostimulatory components, which play a role in several pathological processes. Significant cellular responses to various stimuli involve the formation of inflammasomes, maturation of inflammatory caspases, and caspase-mediated cleavage of gasdermin. The function of pyroptosis in disease is complex but not a simple angelic or demonic role. While inflammatory diseases such as sepsis are associated with uncontrollable pyroptosis, the potent immune response induced by pyroptosis can be exploited as a therapeutic target for anti-tumor therapy. Thus, a comprehensive review of the role of pyroptosis in disease is crucial for further research and clinical translation from bench to bedside. In this review, we summarize the recent advancements in understanding the role of pyroptosis in disease, covering the related development history, molecular mechanisms including canonical, non-canonical, caspase 3/8, and granzyme-mediated pathways, and its regulatory function in health and multiple diseases. Moreover, this review also provides updates on promising therapeutic strategies by applying novel small molecule inhibitors and traditional medicines to regulate pyroptosis. The present dilemmas and future directions in the landscape of pyroptosis are also discussed from a clinical perspective, providing clues for scientists to develop novel drugs targeting pyroptosis.

Thiolutin, a selective NLRP3 inflammasome inhibitor, attenuates cyclophosphamide-induced impairment of sperm and fertility in mice

OBJECTIVE

The activation of the NLRP3 inflammasome has been implicated in male infertility. Our study aimed to investigate the therapeutic role of Thiolutin (THL), an inhibitor of the NLRP3 inflammasome, on oligoasthenospermia (OA) and to elucidate its mechanisms.

MATERIALS AND METHODS

Semen from 50 OA and 20 healthy males were analyzed to assess the sperm quality and levels of inflammatory markers. Their correlation was determined using Pearson's correlation coefficient. The BALB/c mice were intraperitoneal injected by cyclophosphamide at 60 mg/kg/day for five days to induce OA, followed by a two-week treatment with THL or L-carnitine. Reproductive organ size and H&E staining were determined to observe the organ and seminiferous tubule morphology. ELISA and western blotting were utilized to measure sex hormone levels, inflammatory markers, and NLRP3 inflammasome levels. Furthermore, male and female mice were co-housed to observe pregnancy success rates.

RESULTS

OA patients exhibited a decrease in sperm density and motility compared to healthy individuals, along with elevated levels of IL-1β, IL-18 and NLRP3 inflammasome. In vivo, THL ameliorated OA-induced atrophy of reproductive organs, hormonal imbalance, and improved sperm density, motility, spermatogenesis and pregnancy success rates with negligible adverse effects on weight or liver-kidney function. THL also demonstrated to be able to inhibit the activation of NLRP3 inflammasome and associated proteins in OA mice.

DISCUSSION

THL can improve sperm quality and hormonal balance in OA mice through the inhibition of NLRP3 inflammasome activation. Thus, THL holds promising potential as a therapeutic agent for OA.