Inhibiting NLRP3 Inflammasome Research Articles

P16INK4a Aggravated Sepsis-associated Cardiac Injury by Inhibiting the PI3K/AKT Pathway and Inducing Redox Imbalance.

Severe sepsis can promote myocardial injury and cardiac dysfunction, but role of p16 in sepsis-induced myocardial injury remains undefined. PBMCs were collected from patients. Expression of inflammatory factors and NLRP3 pathway were detected by Western blotting and qPCR in WT and p16KO mice. Then detect cardiomyocyte apoptosis and ROS levels in vitro. Detailed pathways and mechanisms were revealed through quantitative proteomic analysis combined with GSEA and KEGG analysis. p16 was overexpressed in PBMCs of patient. p16 knockout alleviated cardiac dysfunction in LPS-induced mice and inhibited NLRP3 inflammasome pathway in vivo and in vitro. Quantitative proteomic analysis revealed that p16 knockout contributed to the activation of the PI3K/Akt pathway in LPS-induced cardiac injury. p16 knockout promoted activation of the PI3K/Akt pathway and ameliorated NLRP3 pathway inhibition and redox imbalance thus improving cardiac function in LPS-induced cardiomyopathy mice.

Targeting the NLRP3 inflammasome as a novel therapeutic target for osteoarthritis.

Osteoarthritis,the most common arthritic condition, is an age-related progressive disease characterized by the loss of cartilage and synovial inflammation in the knees and hips. Development of pain, stiffness, and considerably restricted mobility of the joints are responsible for the production of matrix metalloproteinases and cytokines. Although several treatments are available for the management of this disease condition, they possess limitations at different levels. Recently, efforts have focused on regulating the production of the NLRP3 inflammasome, which plays a critical role in the disease's progression due to its dysregulation. Inhibition of NLRP3 inflammasome has shown the potential to modulate the production of MMP-13, caspase-1, IL-1β, etc., which has been reflected by positive responses in different preclinical and clinical studies. Aiming inhibition of this NLRP3 inflammasome, several compounds are in different stages of research owing to bring a novel agent for the treatment of osteoarthritis. This review summarizes the mechanistic pathways linking NLRP3 activation to osteoarthritis development and discusses the progress in new therapeutics aimed at effective treatment.

Berberine Inhibits the Disruption of the Blood-Brain Barrier and Glial Cell Activation in a Rat Model of Acute Hepatic Encephalopathy.

Hepatic encephalopathy (HE) is a complex neurological disorder in individuals with liver diseases, necessitating effective neuroprotective interventions to alleviate its adverse outcomes. Berberine (BBR), a natural compound with well-established anti-fibrotic and neuroprotective properties, has not been extensively studied in the context of glial activation under hyperammonaemic conditions. This study evaluates the neuroprotective potential of BBR in a thioacetamide (TAA)-induced HE rat model, focusing on its effects on glial activation and NLRP3 inflammasome signalling. Neurological impairments were assessed using open field tests and sensory analysis. Western blotting was performed to evaluate the expression of glial and neuronal markers, tight junction proteins and NLRP3 inflammasome components in the cortex and hippocampus. Histopathological and molecular changes were further examined using H&E, immunohistochemistry and immunofluorescence staining. BBR treatment significantly improved behavioural abnormalities and reduced systemic ammonia levels in TAA-exposed rats. It restored blood-brain barrier integrity, as evidenced by reduced tight junction protein degradation. BBR inhibited the expression of NLRP3 inflammasome markers, including caspase-1, IL-1β, ASC, and NF-κB, while reducing glial cell activation (IBA-1 and GFAP). Notably, BBR diminished NLRP3 expression in glial cells, indicating its potent anti-inflammatory effects. Additionally, BBR preserved neuronal integrity, as demonstrated by the maintained expression of MAP-2 and NeuN and reduced cleaved Gasdermin D levels. These findings suggest that BBR alleviates behavioural and molecular abnormalities in HE through NLRP3 inflammasome inhibition, highlighting its potential as a therapeutic agent for managing HE.

Anti-Inflammatory and Anti-Migratory Effects of Morin on Non-Small-Cell Lung Cancer Metastasis via Inhibition of NLRP3/MAPK Signaling Pathway

Non-small-cell lung cancer (NSCLC) remains the leading cause of cancer-related deaths globally, with a persistently low five-year survival rate of only 14–17%. High rates of metastasis contribute significantly to the poor prognosis of NSCLC, in which inflammation plays an important role by enhancing tumor growth, angiogenesis, and metastasis. Targeting inflammatory pathways within cancer cells may thus represent a promising strategy for inhibiting NSCLC metastasis. This study evaluated the anti-inflammatory and anti-metastatic properties of morin, a bioactive compound derived from a Thai medicinal herb, focusing on its effects on NLRP3 inflammasome-mediated pathways in an in vitro NSCLC model. The A549 and H1299 cell lines were stimulated with lipopolysaccharide (LPS) and adenosine triphosphate (ATP) to activate the NLRP3 pathway. The inhibition effects exhibited by morin in reducing pro-inflammatory secretion in LPS- and ATP-stimulated NSCLC cells were assessed by ELISA, while wound healing and trans-well invasion assays evaluated its impact on cell migration and invasion. RT-qPCR measurement quantified the expression of inflammatory genes, and zymography and Western blotting were used to examine changes in invasive protein levels, epithelial-to-mesenchymal transition (EMT) markers, and underlying molecular mechanisms. Our findings demonstrated the significant ability of morin to decrease the production of IL-1β, IL-18, and IL-6 in a dose-dependent manner (p < 0.05), as well as suppress NSCLC cell migration and invasion. Morin downregulated invasive proteins (MMP-2, MMP-9, u-PAR, u-PA, MT1-MMP) and EMT markers (fibronectin, N-cadherin, vimentin) (p < 0.01) while also reducing the mRNA levels of NLRP3, IL-1β, IL-18, and IL-6. Mechanistic investigations revealed that morin suppressed NLRP3 inflammasome activity and inactivated MAPK pathways. Specifically, it decreased the expression of NLRP3 and ASC proteins and reduced caspase-1 activity, while reducing the phosphorylation of ERK, JNK, and p38 proteins. Collectively, these findings suggest that morin’s inactivation of the NLRP3 inflammasome pathway could offer a novel therapeutic strategy for counteracting pro-tumorigenic inflammation and metastatic progression in NSCLC.

Chlorogenic acid inhibits NLRP3 inflammasome activation through Nrf2 activation in diabetic nephropathy

Diabetic nephropathy (DN) is the single largest cause of end-stage renal disease (ESRD). Inflammation reaction mediated by NLRP3 inflammasome and Nrf2-related oxidative stress have been considered to play a very important role in the progress of diabetic nephropathy (DN). Effective drugs for the treatment of diabetic nephropathy still need to be explored. Chlorogenic acid (CGA) is a kind of polyphenol with a Nrf2 activation property widely existed in nature. The aims of this study were to evaluate the renoprotective effect of CGA and to elucidate the anti-inflammation mechanisms involved. In the present study, we established a diabetic rat model to investigate the renoprotective effect of CGA in vivo. The results show that the level of serum creatinine (Scr), blood urea nitrogen (BUN), and urinary protein excretion in diabetic rats were significantly decreased after CGA intervention. CGA administration can active the Nrf2 pathway and inhibit NLRP3 inflammasome activation. Notably, Nrf2 siRNA transfection nullified the inhibitory effects of CGA on NLRP3 inflammasome activation in vitro. To summarize, our present study provided evidence that chlorogenic acid can slow the progression of diabetic nephropathy progression, and the effect is associated with suppression of NLRP3 inflammasome activation via through modulation of the Nrf2 pathway, suggesting its therapeutic implications for diabetic nephropathy.

Exploring the health benefits of food bioactive compounds from a perspective of NLRP3 inflammasome activation: an insight review.

The food industry has been focusing on food bioactive compounds with multiple physiological and immunological properties that benefit human health. These bioactive compounds, including polyphenols, flavonoids, and terpenoids, have great potential to limit inflammatory responses especially NLRP3 inflammasome activation, which is a key innate immune platform for inflammation. Current studies have revealed numerous food bioactive compounds with promising activities for unraveling immune metabolic disorders and excessive inflammatory responses by directly and indirectly regulating the NLRP3 inflammasome activation. This review explores the food hazards, including microbial and abiotic factors, that may trigger NLRP3-mediated illnesses and inflammation. It also highlights bioactive compounds in food that can suppress NLRP3 inflammasome activation through various mechanisms, linking its activation and inhibition to different pathways. Especially, this review provided further insight into NLRP3-related targets where food bioactive compounds can interact to block the NLRP3 inflammasome activation process, as well as mechanisms on how these compounds facilitate inactivation processes.

Artemisitene ameliorates carbon tetrachloride-induced liver fibrosis by inhibiting NLRP3 inflammasome activation and modulating immune responses.

Artemisitene (ATT), an artemisinin (ART) analog retaining the endoperoxide moiety and incorporating an additional α, β-unsaturated carbonyl structure, exhibits enhanced biological activities. However, its therapeutic effects on liver fibrosis remain unclear. In this study, we demonstrated that ATT significantly alleviated liver inflammation and fibrosis induced by carbon tetrachloride (CCL4) in mice. ATT treatment markedly reduced the count of neutrophils in the liver, as well as macrophages in both the liver and spleen. Additionally, the frequencies of Th2 and Th17 cells were significantly lowered, while Th1 cells frequency and the Th1/Th2 index were notably increased. The frequency of ILC2 cells, correlated with ST2 and IL-33 expression levels, was also significantly lowered. Consistently, ATT inhibited NLRP3 inflammasome activation, which was positively associated with AST and ALT levels, and with the count of Neutrophils, macrophages, and ILC2 cells, but negatively correlated with Th1frequeny. Furthermore, liver fibrosis severity showed a significant positive correlation with neutrophil and Th17 cell counts in the liver, and a negative correlation with Th1 cell count and the Th1/Th2 index. Therefore, ATT alleviated CCL4-induced mice liver fibrosis through NLRP3 inflammasome inhibition and immunomodulation.

The IRE1-XBP1 Axis Regulates NLRP3 Inflammasome-Mediated Microglia Activation in Hypoxic Ischemic Encephalopathy.

Hypoxic-ischemic encephalopathy (HIE) is a perinatal injury caused by cerebral hypoxia and reduced blood perfusion. Microglia activation-induced neuroinflammatory injury is a leading cause of neuron loss and brain injury. Efficient treatment strategies are still required further investigation. Our study is aimed to investigate the role of IRE1-XBP1 inhibitor 4μ8С in HIE. Rat pups (7 d) were used to establish HIE model using unilateral carotid artery ligation and hypoxia. A series of experiments including Western blot, Morris water maze test, TTC staining, RT-qPCR, TUNEL staining, and immunofluorescence staining were operated to evaluate the role of 4μ8С in HIE. 4μ8С treatment effectively reduced phosphorylated IRElα and XBP1 protein levels. 4μ8С treatment improves cognition and learning abilities of HIE rats. 4μ8С treatment alleviated brain infarction and cell apoptosis in HIE rats. 4μ8С treatment inhibited NLRP3 inflammasome activation-mediated microglia activation and inflammatory response. In conclusion, 4μ8С suppressed microglia and NLRP3 inflammasome activation by inactivating IRE1/XBP1 axis during HIE development, which revealed IRE1α inhibition as a novel mechanism for neuron protection.

Forsythoside B Ameliorates Neuroinflammation via Inhibiting NLRP3 Inflammasome of Glial Cells in Experimental Autoimmune Encephalomyelitis Mice.

Neuroinflammation mediated by glial cells plays a crucial role in demyelination in experimental autoimmune encephalomyelitis (EAE), a multiple sclerosis (MS) model. Forsythoside B (FTS·B), a natural phenylethanoid glycoside isolated from the dried fruits and leaves of Forsythia suspensa (Thunb.) Vahl, has been found to have antioxidant, anti-apoptotic, and anti-inflammatory properties. However, there is currently no report or research on the effectiveness of FTS·B treatment for EAE. The aim of this study was to investigate the neuroprotective properties of (FTS·B) on EAE and reveal its potential mechanisms. Myelin oligodendrocyte glycoprotein-induced EAE mice were randomly categorized into the control, EAE model, and FTS·B treatment groups. Behavioral testing, pathology, immunohistochemistry, immunofluorescence staining, and western blot analysis of spinal cord tissue were used to determine the effects and mechanisms of FTS·B on EAE in mice. We found that FTS·B treatment could significantly alleviate and reduce the clinical symptoms and morbidity of EAE, respectively. In addition, FTS·B administration reduced inflammatory response and demyelination by inhibiting glial cell activation in the spinal cord of EAE mice. Further experiments confirmed that FTS·B inhibited the formation of NLRP3 inflammasome in microglia and astrocytes, thereby suppressing neuroinflammation and GSDMD-mediated pyroptosis. Altogether, these results suggest that FTS·B treatment attenuates central neuroinflammation and pyroptosis by inhibiting NLRP3 inflammasome of glial cells in EAE mice.

Targeted isolation of diketopiperazines from a deep-sea derived fungus with anti-neuroinflammatory effects.

Prenylated indole diketopiperazines represent a diverse array of alkaloids with complex chemical scaffolds and with a wide range of biological activities. Aiming to discover bioactive metabolites with structural novelty, genomic annotation in association with the MS/MS-based molecular networking demonstrated a deep-sea derived fungus Aspergillus puulaauensis F77 containing a profile of diketopiperazines. Targeted separation of the cultured fungus led to the isolation of 19 undescribed austamide-type diketopiperazines namely versicoines A-S. Their structures were elucidated by the 2D NMR data, in association with Snatzke'method, ECD calculations, and single-crystal X-ray diffraction data for configurational assignments. Versicoine N-S represent a unique class of austamide-type alkaloids with a spirocenter at C-3. Bioassay results demonstrated versicoine N and relevant analogs possessing inhibitory effects against NO production in LPS-stimulated BV-2 cells. Further mechanistic investigation demonstrated the significant inhibition of versicoine N against p65 expression and its nuclear translocation, along with the inhibition toward phosphorylation of IKK/IκB in NF-κB signaling pathway. In addition, versicoine N also inhibited NLRP3 inflammasome activation and its related proteins, including caspase 1, pro-caspase1, IL-1β and pro-IL-1β. This study largely extends the chemical diversity of austamide-type alkaloids, and provides promising lead compounds for anti-neuroinflammation.

Transcranial focused ultrasound stimulation alleviates NLRP3-related neuroinflammation induced by ischemic stroke via regulation of the Nespas/miR-383-3p/SHP2 pathway

Transcranial focused ultrasound stimulation (tFUS) has emerged as a promising therapeutic strategy for mitigating brain injury in animal models. In this study, the effects and mechanisms of tFUS on ischemic stroke were explored in a transient middle cerebral artery occlusion (MCAO) rat model. Low-intensity tFUS was administered to the ischemic hemisphere 24 h post-MCAO for seven consecutive days. Neurological function was evaluated through neurobehavioral assessments following tFUS treatment. Western blotting, immunofluorescence staining, and quantitative real-time PCR were performed to examine the impact of tFUS on NLRP3-related neuroinflammation using brain tissues from MCAO rats and BV2 cells subjected to oxygen glucose deprivation/reperfusion (OGD/R). Additionally, RNA sequencing and cell transient transfection were employed to elucidate the underlying mechanisms. The findings revealed that tFUS improved neurobehavioral performance, reduced infarct size, and suppressed NLRP3 inflammasome activation seven days post-MCAO. Notably, Nespas expression was significantly elevated in tFUS-treated rats, whereas Nespas silencing exacerbated neurological deficits and enhanced NLRP3 activation. Moreover, Nespas positively regulated src homology 2 domain-containing tyrosine phosphatase-2 (SHP2), and SHP2 inhibition significantly amplified NLRP3 activation. Mechanistic in vitro studies further demonstrated that Nespas attenuated microglial NLRP3 activation via the Nespas/miR-383-3p/SHP2 pathway. These results suggest that the neuroprotective effects of tFUS are likely mediated through the upregulation of Nespas and suppression of NLRP3 via the Nespas/miR-383-3p/SHP2 axis, offering new insights into the molecular mechanisms supporting tFUS as a potential therapeutic approach for stroke-induced brain injury.

NLRP3 Inhibitor Alleviates Glycemic Variability-Induced Cognitive Impairment in Aged Rats with Type 2 Diabetes Mellitus

Glycemic variability (GV) markedly exacerbates cognitive impairment in elderly patients with type 2 diabetes mellitus (T2DM), in part through chronic inflammation. This study investigated the therapeutic efficacy of the NLRP3 inflammasome inhibitor MCC950 in mitigating GV-induced cognitive impairment in an aged rat model of T2DM. Aged Sprague-Dawley rats with induced T2DM were subjected to GV conditions, and the effects of MCC950 were evaluated through measurement of body weight, blood glucose, lipid profiles, insulin level, inflammatory markers, and cognitive function. Transcriptomic analysis was performed on the hippocampus and prefrontal cortex. Treatment with MCC950 significantly alleviated weight loss and hyperglycemia in the GV group compared with the control group. MCC950 also reduced the levels of cholesterol, triglycerides, and pro-inflammatory markers (interleukin-1β (IL-1β) and interleukin-18 (IL-18)). Most notably, MCC950 improved spatial learning and memory retention in the GV group. Immunohistochemical analysis indicated a reduction in inflammasome activation and an increase in the expression level of the neuronal marker NeuN in the hippocampus. Transcriptomic analysis revealed that MCC950 altered neuroactive ligand-receptor interaction pathways in the hippocampus and influenced receptor binding and cell adhesion processes in the prefrontal cortex. These findings validated the efficacy of NLRP3 inhibitor in mitigating GV-induced cognitive impairment in elderly rats with T2DM and provided the basis for subsequent clinical studies exploring the broader potential of NLRP3-targeted interventions in addressing diabetes-associated cognitive impairment.

DAG-MAG-ΒHB: A Novel Ketone Diester Modulates NLRP3 Inflammasome Activation in Microglial Cells in Response to Beta-Amyloid and Low Glucose AD-like Conditions.

A neuroinflammatory disease such as Alzheimer's disease, presents a significant challenge in neurotherapeutics, particularly due to the complex etiology and allostatic factors, referred to as CNS stressors, that accelerate the development and progression of the disease. These CNS stressors include cerebral hypo-glucose metabolism, hyperinsulinemia, mitochondrial dysfunction, oxidative stress, impairment of neuronal autophagy, hypoxic insults and neuroinflammation. This study aims to explore the efficacy and safety of DAG-MAG-ΒHB, a novel ketone diester, in mitigating these risk factors by sustaining therapeutic ketosis, independent of conventional metabolic pathways. We evaluated the intestinal absorption of DAG-MAG-ΒHB and the metabolic impact in human microglial cells. Utilizing the HMC3 human microglia cell line, we examined the compound's effect on cellular viability, Acetyl-CoA and ATP levels, and key metabolic enzymes under hypoglycemia. Additionally, we assessed the impact of DAG-AG-ΒHB on inflammasome activation, mitochondrial activity, ROS levels, inflammation and phagocytic rates. DAG-MAG-ΒHB showed a high rate of intestinal absorption and no cytotoxic effect. In vitro, DAG-MAG-ΒHB enhanced cell viability, preserved morphological integrity, and maintained elevated Acetyl-CoA and ATP levels under hypoglycemic conditions. DAG-MAG-ΒHB increased the activity of BDH1 and SCOT, indicating ATP production via a ketolytic pathway. DAG-MAG-ΒHB showed remarkable resilience against low glucose condition by inhibiting NLRP3 inflammasome activation. In summary, DAG-MAG-ΒHB emerges as a promising treatment for neuroinflammatory conditions. It enhances cellular health under varying metabolic states and exhibits neuroprotective properties against low glucose conditions. These attributes indicate its potential as an effective component in managing neuroinflammatory diseases, addressing their complex progression.

Commentary: BAFF blockade attenuates DSS-induced chronic colitis via inhibiting NLRP3 inflammasome and NF-кB activation.

Commentary: BAFF blockade attenuates DSS-induced chronic colitis via inhibiting NLRP3 inflammasome and NF-кB activation.

HDAC10 switches NLRP3 modification from acetylation to ubiquitination and attenuates acute inflammatory diseases

BackgroundThe NOD-like receptor protein (NLRP)3 inflammasome is at the signaling hub center to instigate inflammation in response to pathogen infection or oxidative stress, and its tight control is pivotal for immune defense against infection while avoiding parallel intensive inflammatory tissue injury. Acetylation of NLRP3 is critical for the full activation of NLRP3 inflammasome, while the precise regulation of the acetylation and deacetylation circuit of NLRP3 protein remained to be fully understood.MethodsThe interaction between histone deacetylase 10 (HDAC10) and NLRP3 was detected by immunoprecipitation and western blot in the HDAC10 and NLRP3 overexpressing cells. The role of HDAC10 in NLRP3 inflammasome activation was measured by immunofluorescence, real-time PCR and immunoblotting assay in peritoneal macrophages and bone marrow-derived macrophages after the stimulation with LPS and ATP. To investigate the role of HDAC10 in NLRP3-involved inflammatory diseases, the Hdac10 knockout (Hdac10−/−) mice were used to construct the LPS-induced acute endotoxemia model and folic acid-induced acute tubular necrosis model. Tissue injury level was analyzed by hematoxylin and eosin staining, and the serum level of IL-1β was measured by enzyme-linked immunosorbent assay (ELISA). The conservative analysis and immunoprecipitation assay were performed to screen the precise catalytic site regulated by HDAC10 responsible for the switching from the acetylation to ubiquitination of NLRP3.ResultsHere we demonstrated that HDAC10 directly interacted with NLRP3 and induced the deacetylation of NLRP3, thus leading to the inhibition of NLRP3 inflammasome and alleviation of NLRP3 inflammasome-mediated acute inflammatory injury. Further investigation demonstrated that HDAC10 directly induced the deacetylation of NLRP3 at K496 residue, thus switching NLRP3 acetylation to the ubiquitination modification, resulting in the proteasomal degradation of NLRP3 protein. Thus, this study identified HDAC10 as a new eraser for NLRP3 acetylation, and HDAC10 attenuated NLRP3 inflammasome involved acute inflammation via directly deacetylating NLRP3.ConclusionsThis study indicated that HDAC10 switched NLRP3 modification from acetylation to ubiquitination and attenuated acute inflammatory diseases, thus it provided a potential therapeutic strategy for NLRP3 inflammasome-associated diseases by targeting HDAC10.

Conjugated bile acids alleviate acute pancreatitis through inhibition of TGR5 and NLRP3 mediated inflammation

IntroductionSevere acute pancreatitis (SAP) is a crucial gastrointestinal disease characterized by systemic inflammatory responses and persistent multiple organ failure. The role of bile acids (BAs) in diverse inflammatory diseases is increasingly recognized as crucial, but the underlying role of BA conjugation remains elusive.ObjectivesOur study aim to investigate the potential role of conjugated bile acids in SAP and reveal the molecular mechanisms underlying its regulatory effects. We hypothesized that taurochenodeoxycholic acid (TCDCA) and glycochenodeoxycholic acid (GCDCA) could protect SAP through inhibiting the activation of NLRP3 inflammasomes via the TGR5 pathway in macrophages.MethodsTo test our hypothesis, we used BA-CoA: amino acid N-acyltransferase knockout (Baat−/−) mice and established SAP mouse models using caerulein- and sodium taurocholate- induced. We utilized a range of methods, including pathology sections, qRT-PCR, immunofluorescence, Western blotting, and ELISA, to identify the mechanisms of regulation.ResultsBA-CoA: Amino acid N-acyltransferase knockout (Baat−/−) mice significantly exacerbated pancreatitis by increasing pancreatic and systemic inflammatory responses and pancreatic damage in SAP mouse models. Moreover, the serum TCDCA levels in Baat−/− mice were lower than those in wild-type (WT) mice with or without SAP, and GCDCA and TCDCA showed stronger anti-inflammatory effects than chenodeoxycholic acid (CDCA) in vitro. TCDCA treatment alleviated SAP in a Takeda G protein-coupled receptor 5 and NOD-like receptor family, pyrin domain containing 3—dependent manner in vivo. Reinforcing our conclusions from the mouse study, clinical SAP patients exhibited decreased serum content of conjugated BAs, especially GCDCA, which was inversely correlated with the severity of systemic inflammatory responses.ConclusionConjugated bile acids significantly inhibit NLRP3 inflammasome activation by activating TGR5 pathway, thereby alleviating pancreatic immunopathology. The results provide new insights into the variability of clinical outcomes and paves the way for developing more effective therapeutic interventions for AP.

Rosthornin B alleviates inflammatory diseases via directly targeting NLRP3.

Aberrant activation of the NLRP3 inflammasome contributes to the evolution of diverse inflammatory diseases. Inhibition of the NLRP3 inflammasome has been proven to be an effective treatment strategy for NLRP3-driven diseases. This study revealed that multiple natural diterpenes from Isodon plants can inhibit the NLRP3 inflammasome, among which Rosthornin B (Ros B) exhibited the best inhibitory effect, with an IC50 of 0.39 μM. Further study revealed that Ros B directly interacts with NLRP3, thereby restraining NEK7-NLRP3 interaction and inhibiting NLRP3 inflammasome assembly and activation. Remarkably, Ros B had a significant therapeutic benefit in mouse models of NLRP3-driven septic shock, peritonitis, and colitis. Our study has identified a series of natural diterpenes that target the NLRP3 inflammasome. These natural diterpenes, especially those with low IC50 values, may lead to the development of new drugs and potential clinical therapies for diseases driven by NLRP3 inflammasome activation.

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 thecardiotoxic effects of DOX and suppresses NLRP3 inflammasome in the mouse model, suggesting that THL as a potential drug for DOXIC.

Protective Effects of Antcin H Isolated from Antrodia cinnamomea Against Neuroinflammation in Huntington's Disease via NLRP3 Inflammasome Inhibition.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat in the huntingtin (HTT) gene. When the CAG repeat exceeds 36, it results in the accumulation of the mutant HTT (mHTT) protein in neurons and glial cells. Key pathological mechanisms in HD include excitotoxicity, energy dysfunction, impaired mitochondrial function, increased oxidative stress, and neuroinflammation. The NLRP3 inflammasome is a multimeric protein complex element of NLRP3, ASC, and caspase-1, which regulates interleukin (IL)-1β and IL-18 secretion. The NLRP3 inflammasome plays an important role in inflammatory reactions and is involved in the pathogenesis of several neurodegenerative diseases. We have previously demonstrated high NLRP3 inflammasome expression levels in the striatum of R6/2 mice (a transgenic HD mouse model). Systematic administration of an NLRP3 inhibitor (MCC950) to R6/2 mice suppressed the NLRP3 inflammasome, decreased IL-1β and reactive oxygen species production, and reduced neuronal toxicity, suggesting protective effects against HD. Antrodia cinnamomea is an indigenous medicinal fungus in Taiwan, which shows diverse medicinal and pharmacological activities, but its effects in HD are not well understood. Herein, we report that systematic administration of Antcin-H isolated from A. cinnamomea to R6/2 mice suppressed the NLRP3 inflammasome, IL-1β production, and reduced neuronal toxicity. Most importantly, oral administration of Antcin-H reduced disease progression by increasing neuronal survival, reducing neuroinflammation during an extended lifespan, and improving motor dysfunction in R6/2 mice. Taken together, our data suggest that Antcin-H has therapeutic potential for treating HD.

Irisin alleviates the pyroptosis of β cells in T2DM by inhibiting NLRP3 inflammasome through regulating miR-19b-3p/SOCS3/STAT3 axis mediated autophagy.

The purpose of this study was to analyze the mechanism by which irisin affects β-cell pyroptosis in type 2 diabetes mellitus (T2DM). The in vivo T2DM model was established by raised with high-fat diet and intraperitoneally injection of streptozocin. Min6 cells were divided into four groups: negative control (NC), high glucose (HG), HG + irisin, and HG + irisin+3-MA. The cell viability was determined by CCK-8 assay. Dual-luciferase gene reporter assay was conducted to confirm the binding between miR-19b-3p and SOCS3. The expression level of FNDC5 and GSDMD was visualized using the immunofluorescence assay. The protein level of FNDC5, Beclin1, LC3II/I, NLRP3, cleaved-caspase-1, GSDMD-N, STAT3, p-STAT3, and SOCS3 was determined by Western blotting. The secretion of irisin, lactate dehydrogenase (LDH), and insulin was checked by ELISA. In vivo results showed that pathological changes in islet tissues with declined number of β cells, elevated FBG value, decreased FIN and HOMA-β value, elevated autophagy-associated proteins expressions, and activated NLRP3 signaling in T2DM mice, which were dramatically reversed by FNDC5 overexpression. Furthermore, the declined level of miR-19b-3p and p-STAT3, as well as the upregulation of SOCS3, was greatly rescued by FNDC5 overexpression. The in vitro data confirmed the binding site between SOCS3 and miR-19b-3p. SOCS3 was downregulated and p-STAT3 was upregulated in miR-19b-3p mimic-treated Min6 cells. In HG-stimulated Min6 cells, the elevated cell viability, increased production of insulin, decreased release of LDH, and inactivated NLRP3 signaling induced by irisin were abolished by miR-19b-3p inhibitor and STAT3 inhibitor. The increased level of autophagy-related proteins and activated SOCS3/STAT3 axis induced by irisin in HG-stimulated Min6 cells were abolished by miR-19b-3p inhibitor. The inhibitory effect of irisin against NLRP3 signaling in HG-stimulated Min6 cells was abrogated by 3-MA. In conclusion, irisin alleviated the pyroptosis of β cells in T2DM by inhibiting NLRP3 signaling through miR-19b-3p/SOCS3/STAT3 axis mediated autophagy.