NLRP3 Signaling Pathway Research Articles

Benzoylmesaconine mitigates NLRP3 inflammasome-related diseases by reducing intracellular K+ efflux and disrupting NLRP3 inflammasome assembly

BackgroundBenzoylmesaconine (BMA), a major alkaloid derived from the traditional Chinese medicine Aconitum carmichaeli Debx, exhibits potent anti-inflammatory properties. However, the precise mechanism underlying its action remains unclear. PurposeThis study aimed to investigate the inhibitory mechanism of BMA on the NLRP3 inflammasome and assess its therapeutic efficacy in NLRP3-related metabolic diseases. MethodsA classic NLRP3 inflammasome-activated bone marrow-derived macrophage (BMDM) model was established to evaluate BMA's effects on NLRP3 upstream and downstream protein expression, as well as pyroptosis. Two distinct animal disease models, MSU-induced gouty arthritis and DSS-induced colitis, were utilized to validate BMA's anti-inflammatory activity in vivo. ResultsIn vitro findings revealed that BMA can suppress NLRP3 inflammasome activation by inhibiting interleukin-1β (IL-1β) secretion and GSDMD-N protein expression. This mechanism involved blocking intracellular K+ efflux and interfering with the formation of NLRP3 inflammasomes. In vivo studies demonstrated that BMA significantly alleviated inflammatory symptoms in MSU-induced acute gout and DSS-induced colitis models. ConclusionThese findings suggest that BMA effectively inhibits the activation of the NLRP3 signaling pathway through dual mechanisms: reducing intracellular K+ efflux and disrupting NLRP3 inflammasome assembly. This multifaceted action highlights the therapeutic potential of BMA for NLRP3-related diseases.

Neuroprotective effect of empagliflozin against doxorubicin-induced chemobrain in rats: Interplay between SIRT-1/MuRF-1/PARP-1/NLRP3 signaling pathways and enhanced expression of miRNA-34a and LncRNA HOTAIR

Chemobrain, a challenging side effect of doxorubicin (DOX)-based chemotherapy, impairs cognitive abilities in cancer survivors. DOX triggers chemobrain via oxidative stress, leading to inflammation and apoptosis. Empagliflozin (EMPA), a sodium glucose co-transporter-2 inhibitor, demonstrated neuroprotective effects by reducing reactive oxygen species (ROS) and inflammation, but its protective mechanisms against DOX-induced chemobrain is not fully known. Thus, this study aimed to investigate EMPA’s neuroprotective effects on DOX-induced chemobrain in rats and to uncover the underlying protective mechanisms. Fifty male Wistar rats were divided into control, EMPA, DOX (2 mg/kg, IP, once/week for 4 weeks), and two treated groups (DOX+ EMPA 5 and 10 mg/kg/day, PO, for 4 weeks). Behavioral tests showed improved memory, motor performance, and reduced anxiety in EMPA-treated groups compared to DOX, with superior results at the higher dose. Histopathological analysis revealed increased intact neurons in the cortex and hippocampus in EMPA-treated groups, with 346.4 % increase in CA3 (p < 0.0001), 19.1 % in dentate gyrus (p = 0.0006), and 362.6 % in cortex (p < 0.0001) in the high-dose EMPA group. Biochemical investigations of the high-dose EMPA group revealed significant decreases in inflammatory and apoptotic markers (JNK/PARP-1/NLRP3/MuRF-1/FOXO-1), increased SIRT-1 protein expression by 389.9 % (p < 0.0001), and reduced miRNA-34a and LncRNA HOTAIR gene expression (50.4 % and 53.4 % respectively, p < 0.0001) relative to DOX group. Conclusively, EMPA demonstrated superior behavioral and histopathological outcomes particularly at higher dose, positioning it as a promising neuroprotective candidate against DOX-induced chemobrain, possibly through modulating SIRT-1, NF-κb, NLRP3, and oxidative stress pathways.

Electroacupuncture pretreatment inhibits the TLR4/NF-κB/TXNIP/NLRP3 signaling pathway and modulates microglial polarization to alleviate cerebral ischemia-reperfusion injury in rats

Cerebral ischemia–reperfusion injury is frequently associated with neuroinflammation. The modulation of microglial polarization presents a promising approach for addressing cerebral ischemia–reperfusion injury. While electroacupuncture preconditioning has demonstrated efficacy in the management of ischemic stroke, the underlying therapeutic mechanisms remain inadequately understood. The investigation focused on elucidating the relationship between alterations in the TLR4/NF-κB/TXNIP/NLRP3 signaling pathway and microglial polarization subsequent to EA pretreatment. Established a middle cerebral artery occlusion (MCAO) rat model following electroacupuncture (EA) treatment at the Baihui (GV 20) acupoint. Male Sprague-Dawley rats were randomly assigned to the sham, Ischemia/Reperfusion (I/R), I/R + EA groups (n = 6). The results of Nissl Staining and TUNEL Stainingl showed that the number of curative neurons increased significantly after pretreatment, indicating an improvement in neuron formation and an increase in the number of austenite. The level of apoptosis in brain tissue in the I/R group was significantly higher than that in the sham operation group. Electroacupuncture pretreatment can effectively inhibit apoptosis occurrence. In addition, electric acupuncture pretreatment protects rat blood–brain barrier integrity and mitochondrial function. After treatment, the number of M1-type microglia decreased, while the number of M2-type microglia increased. These results suggest that EA preconditioning may alleviate neurological deficits and neuronal apoptosis caused by cerebral I/R injury, while maintaining the integrity of the blood–brain barrier and promoting microglial polarization through the TLR4/NF-κB/TXNIP/NLRP3 signaling pathway. Our findings establish a new molecular mechanism and theoretical foundation for electroacupuncture therapy of ischemic stroke.

Structural elucidation of an active arabinoglucan from Gomphrena globosa and its protection effect and mechanism against metabolic dysfunction-associated steatohepatitis

The flower of Gomphrena globosa (G. globosa.) is used as Chinese traditional medicine and functional food. Extractions from G. globosa. have been reported to exert hepatoprotective effects. We further hypothesized that the polysaccharide components, as a bioactive ingredient, might have anti-fatty and hepatitis function. Here, a novel homogeneous arabinoglucan GGL0.05S1 (Mw = 83.9 kDa) from this flower, was characterized by monosaccharide composition analysis, methylation analysis, and NMR. Structural analysis showed that the backbone of GGL0.05S1 consists of →4)-α-Glcp-(1→ and →4,6)-α-Glcp-(1→ residues, and the branched chain linked to the main chain via C-6 of →4,6)-α-Glcp-(1→ in the form α-Araf-(1 → [4)-α-Glcp-(1]b → (b > 2). In vitro experiments demonstrated that GGL0.05S1 could inhibit lipid deposition and ROS overload in free fatty acid-induced hepatocytes, meanwhile in vivo tests showed that GGL0.05S1 effectively protected against liver injury, steatohepatitis, and fibrosis in a CDA-HFD-fed MASH model. Mechanism study further uncovered that GGL0.05S1 augmented the expression and antioxidant ability of thioredoxin protein that ameliorated oxidative stress, promoted fatty acid β-oxidation and mitophagy, up to reducing lipotoxicity and alleviating inflammation via inhibiting NLRP3 signaling pathway. Overall, GGL0.05S1 might be a potential novel active compound with liver-protective effect from G. globosa., and which is informative for anti-MASH new drug development.

Selenium nanoparticles affect chicken offspring's intestinal health better than other selenium sources

This study aimed to assess the effects of maternal diets containing various selenium (Se) sources on the intestinal mucosal function in the jejunum of chicken offspring. A total of 630, 18-wk-old Hy-Line Grey hens and 70 18-wk-old Hy-Line Grey breeders were randomly allocated into 7 groups, with 5 replicates in each group (18 hens and tow roosters). After 4 wk of Se depletion, the birds were fed either a nonsupplemented basal diet (control) or the same basal diet supplemented with 0.15 mg/kg selenium nanoparticles (Nano-Se), 0.30 mg/kg Nano-Se, 0.30 mg/kg selenocysteine (Sec), 0.30 mg/kg sodium selenite (SS), 0.30 mg/kg selenomethionine (SeMet), or 0.15 mg/kg Nano-Se + 0.15 mg/kg Sec, for 8 wk. Frtilized eggs were collected and incubated during the final week of the experiment. Jejunal tissues from embryonic d 18 and the hatch day were collected for analysis, and the 7-d survival rate of the offspring was recorded. Compared to the control, the maternal diet of 0.30 mg/kg Nano-Se, 0.30 mg/kg Sec, and 0.30 mg/kg SeMet significantly increased the survival of 7-day-old offspring (P < 0.05). The maternal diet supplemented with 0.30 mg/kg Nano-Se significantly increased intestinal villus height and the villus height/crypt depth ratio in chicks at embryonic d 18 and in 1-day-old (P < 0.05). The maternal diet containing 0.30 mg/kg Nano-Se and Sec increased the mRNA expression levels of tight junction proteins in 1-day-old offspring (P < 0.05). Supplemental 0.30 mg/kg Nano-Se significantly increased the mRNA expression levels of marker genes in intestinal enteroendocrine, stem, and Paneth cells (P < 0.05). In 1-day-old chicks, the number of intestinal goblet cells, as well as the mRNA expression levels of intestinal mucin2 (Muc2) and goblet cell differentiation factors (Spdef and C-myc), were the highest in diets supplemented with 0.30 mg/kg Nano-Se. Moreover, the expression levels of intestinal Muc2 and Spdef in chicks at embryonic d 18 was the highest with 0.30 mg/kg Nano-Se supplementation (P < 0.05). Supplementing with 0.30 mg/kg Nano-Se significantly reduced reactive oxygen species levels and decreased the mRNA expression levels of apoptosis-related genes in 1-day-old chicks (P < 0.05). Additionally, 0.30 mg/kg Nano-Se supplementation significantly down-regulated NLRP3 pathway gene expression in 1-day-old chicks (P < 0.05). In conclusion, maternal dietary supplementation with Nano-Se improved jejunal microarchitecture, antioxidant levels, and the expression of tight-junction protein in chicken offspring along with supporting goblet cell development by inhibiting the NLRP3 signaling pathway.

Tangzu granule alleviate neuroinflammation in diabetic peripheral neuropathy by suppressing pyroptosis through P2X7R /NLRP3 signaling pathway

Ethnopharmacological relevanceDiabetic peripheral neuropathy (DPN) is a common complication of diabetes mellitus, mainly manifested as paresthesia. Tangzu granule (TZG) is derived from famous traditional Chinese medicine decoctions and optimized by long-term temporary practice. TZG has good efficacy in improving numbness, pain and pruritus of the lower extremities of DPN patients. However, the overall regulatory mechanisms underlying its effects on DPN remain unclear. Aim of the studyThis study aims to explore the potential mechanism of TZG for treating DPN. Materials and methodsSprague-Dawley (SD) rats were used to establish an in vivo model of DPN with streptozotocin (STZ) injection and high-fat diet (HFD) feeding. Additionally, sciatic glial RSC96 cells were induced with high glucose in vitro. SD rats in intervention group received TZG treatment for 12 weeks. After 12 weeks of treatment, sciatic nerve function was evaluated by intelligent hot plate meter and neuro electrophysiology detector. The morphological changes of sciatic nerve cells were observed by hematoxylin-eosin staining and transmission electron microscope. IL-1β, IL-18 inflammatory cytokines, pyroptosis and P2X7R/NLRP3 signaling pathway were observed by Western blotting, immunofluorescence staining and ELISA. ResultsTZG improved nerve conduction velocity and sciatic neuropathy rational structural changes in DPN rats. It also inhibited RSC96 inflammatory response and cell death that induced by high glucose. This may be related to TZG inhibiting P2X7R, decreasing the activation of NLRP3 inflammasomes, down-regulating the levels of pyroptosis proteins such as caspase-1, cleaved caspase-1, gasdermin D (GSDMD), and GSDMD-N, and inhibiting the release of interleuki (IL)-18 and IL-1β inflammatory cytokines. ConclusionsTZG inhibited pyroptosis through P2X7R/NLRP3 signaling pathway, alleviated neuroinflammation, and showed protective effect in the treatment of DPN.

Quercus dentata Thunb. leaves extract inhibits CaOx crystallization and ameliorates ethylene glycol-induced CaOx kidney stones via the OPN/CD44 and NLRP3 pathways

Ethnopharmacological relevanceThe leaves of Quercus dentata Thunb. (QD), a member of the Fagaceae family and genus Quercus, with distributions in China, Japan, Korea, and other regions. As recorded in the Ben Cao Gang Mu (Compendium of Materia Medica) and other classical Chinese medical texts, QD has been traditionally employed in Traditional Chinese Medicine (TCM) for their hemostatic and diuretic effects and has been used to treat urinary stones (Lin Zheng). It is also the main ingredient of the Mishitong capsule (MST), a Chinese patent drug, used for kidney stones and ureteral stones. Nonetheless, the specific active ingredients and the mechanisms of QD in treating kidney stones remain to be elucidated, which is crucial for advancing the scientific understanding and clinical application of this traditional medicine. Aim of studyThis study aimed to identify the active constituents of QD water extract (QDWE), explore its inhibitory effects on kidney stones through in vitro and in vivo studies, and elucidate the underlying mechanisms of the OPN/CD44 axis and the NLRP3 signaling pathway to provide a full understanding of its potential as a novel treatment approach against kidney stones. Materials and methodsThe micromolecular components in the supernatant of QDWE (QDS) were analyzed by UPLC-Q-Exactive-Orbitrap-MS and the monosaccharide composition of the macromolecular polysaccharide components in the crude polysaccharide (QDP) was determined by pre-column derivatization in HPLC. The effects of QDWE, QDS and QDP on the shape, size, and structure of calcium oxalate (CaOx) crystals in vitro were explored by XRD, FTIR and SEM. The effects of QDWE, QDS and QDP on CaOx kidney stones in SD rats induced by ethylene glycol and VD3 were compared in vivo. Furthermore, the underlying mechanisms of OPN/CD44 and NLRP3 pathways were investigated by Western blot analysis. ResultsThere were 32 compounds identified in QDS. The monosaccharide composition ratio of QDP was Man: L-Rha: D-GlcA: D-GalA: D-Glc: D-Gal: L-Ara = 1.01: 22.52: 8.27: 38.61: 3.43: 17.80: 6.38, indicating a mixture of pectin-type acidic heteropolysaccharides. QDP had a more significant inhibitory effect on CaOx crystals in vitro than QDWE, which can inhibit the formation of CaOx monohydrate crystals (COM) and convert them into thermodynamically unstable CaOx dihydrate (COD) crystals. The high dose of QDWE exhibited significant in vivo efficacy (P < 0.05), including anti-calculus, diuretic effects, and kidney protection, marked by decreased calcification and stone formation, alongside improved kidney vitality. Furthermore, the protective effects of QDWE were demonstrated to be associated with the OPN/CD44 and NLRP3 pathways. ConclusionThe studies identified and analyzed the active constituents of QDWE. Among these, QDP significantly inhibited CaOx crystal generation in vitro and could be a potential component for the treatment of urinary stones in QDWE. Moreover, the results indicated that QDWE had a remarkable therapeutic effect on CaOx stones by modulating the OPN/CD44 axis to affect stone formation and the NLRP3 signaling pathway to mediate inflammation, providing an experimental basis for the mechanism of anti-urinary stone and deep development of QD.

Dehydroevodiamine targeting IKKβ to alleviate acute gastric injury via inhibiting the p65/NLRP3 axis

BackgroundAcute gastric injury, a common and recurring global digestive disorder, significantly impairs patient quality of life and overall health. Dehydroevodiamine (DHE), a bioactive natural product derived from Tetradium ruticarpum (A. Juss.) Hartley, shows potential therapeutic effects on acute gastric injury. This study investigates the underlying mechanisms of DHE's alleviating effects on acute gastric injury. MethodsThe gastric mucosal protective effect of DHE was confirmed through in vivo and in vitro acute gastric injury models. Biotin pulldown MS and molecular dynamics simulations identified DHE's target. CETSA and SPR assays validated DHE's affinity for IKKβ. Protein site mutation validation and MST pinpointed the direct binding sites of DHE on IKKβ. Additionally, the potential mechanism by which DHE ameliorates acute gastric injury was elucidated using WB, IHC, and IF methods, and further confirmed by rescue experiments. ResultsDHE effectively ameliorated IDO-induced gastric injury in GES-1 cells and rat gastric mucosa, both in vitro and in vivo. Biotin pulldown MS identified IKKβ as the target of DHE in alleviating gastric injury. CETSA and SPR assays confirmed DHE's direct binding to IKKβ. Molecular dynamics simulations, protein mutation experiments, and MST results pinpointed GLU-149, GLU-49, and ASP-103 in the ATP-binding pocket as the binding sites of DHE on IKKβ. Notably, DHE was found to competitively bind to IKKβ with ATP. Mechanistically, DHE attenuated IDO-induced gastric injury by inhibiting the IKKβ-p65/NLRP3 signaling pathway. Importantly, exogenous activation of IKKβ reversed the therapeutic effect of DHE, indicating that DHE's efficacy depends on IKKβ. ConclusionDHE attenuated IDO-induced gastric injury by inhibiting the IKKβ-p65/NLRP3 signaling pathway. Notably, DHE is a novel ATP-competitive IKKβ inhibitor that prevents phosphorylation by targeting GLU-149, GLU-49, and ASP-103 in the ATP-binding pocket. This study reveals new targets of action for DHE, providing a new molecular basis for using DHE in treating inflammation-related diseases.

1526: S1PR4 antagonist attenuates radiation-induced lung fibrosis via regulating NLRP3 signaling pathway

1526: S1PR4 antagonist attenuates radiation-induced lung fibrosis via regulating NLRP3 signaling pathway

Lcn2 secreted by macrophages through NLRP3 signaling pathway induced severe pneumonia.

Lcn2 secreted by macrophages through NLRP3 signaling pathway induced severe pneumonia.

Progress on the Anti-Inflammatory Activity and Structure-Efficacy Relationship of Polysaccharides from Medical and Edible Homologous Traditional Chinese Medicines.

Medicinal food varieties developed according to the theory of medical and edible homologues are effective at preventing and treating chronic diseases and in health care. As of 2022, 110 types of traditional Chinese medicines from the same source of medicine and food have been published by the National Health Commission. Inflammation is the immune system's first response to injury, infection, and stress. Chronic inflammation is closely related to many diseases such as atherosclerosis and cancer. Therefore, timely intervention for inflammation is the mainstay treatment for other complex diseases. However, some traditional anti-inflammatory drugs on the market are commonly associated with a number of adverse effects, which seriously affect the health and safety of patients. Therefore, the in-depth development of new safe, harmless, and effective anti-inflammatory drugs has become a hot topic of research and an urgent clinical need. Polysaccharides, one of the main active ingredients of medical and edible homologous traditional Chinese medicines (MEHTCMs), have been confirmed by a large number of studies to exert anti-inflammatory effects through multiple targets and are considered potential natural anti-inflammatory drugs. In addition, the structure of medical and edible homologous traditional Chinese medicines' polysaccharides (MEHTCMPs) may be the key factor determining their anti-inflammatory activity, which makes the underlying the anti-inflammatory effects of polysaccharides and their structure-efficacy relationship hot topics of domestic and international research. However, due to the limitations of the current analytical techniques and tools, the structures have not been fully elucidated and the structure-efficacy relationship is relatively ambiguous, which are some of the difficulties in the process of developing and utilizing MEHTCMPs as novel anti-inflammatory drugs in the future. For this reason, this paper summarizes the potential anti-inflammatory mechanisms of MEHTCMPs, such as the regulation of the Toll-like receptor-related signaling pathway, MAPK signaling pathway, JAK-STAT signaling pathway, NLRP3 signaling pathway, PI3K-AKT signaling pathway, PPAR-γ signaling pathway, Nrf2-HO-1 signaling pathway, and the regulation of intestinal flora, and it systematically analyzes and evaluates the relationships between the anti-inflammatory activity of MEHTCMPs and their structures.

Investigation of the role of NLRP3 inflammasome activation in new-generation BCR-ABL1 tyrosine kinase inhibitors-induced hepatotoxicity

New generation BCR-ABL1 TKIs raised attention regarding their adverse effects, including hepatotoxicity. Indeed, bosutinib and nilotinib were associated with severe hepatotoxicity compared with imatinib. Moreover, ponatinib has a boxed warning due to its potential to cause inflammatory liver damage, even death. However, the underlying mechanisms remain unclear. This study aimed to investigate the role of NLRP3 inflammasome activation in the underlying mechanism of ponatinib and bosutinib-induced hepatotoxicity. Furthermore, we determined the initiating event of this adverse outcome pathway by measuring the levels of reactive oxygen species as well as mitochondrial membrane potential in AML12 cells. The results demonstrated that ponatinib or bosutinib markedly inhibited cell viability and caused cytosolic membrane damage in cells. Moreover, drugs (IC50) dramatically induced oxidative stress and mitochondrial membrane potential disruption, which led to upregulation in the expression levels of NLRP3 inflammasome-related genes and proteins, activation of NLRP3 inflammasomes, cleavage of gasdermin-D and caspase-1, secretion of IL-1β, and cytosolic membrane damage. Furthermore, MCC950, a well-known specific inhibitor of NLRP3 inflammasome, and antioxidant N-acetyl-l-cysteine reversed the effects of drugs on the NLRP3 signaling pathway and cytosolic membranes. In summary, NLRP3 inflammasome activation is involved in new-generation BCR-ABL1 TKIs-triggered hepatotoxicity. Mitochondrial damage and reactive oxygen species accumulation were significant upstream signaling events in this signaling pathway.

Specnuezhenide ameliorates hepatic fibrosis via regulating SIRT6-Mediated inflammatory signaling cascades

Ethnopharmacological relevanceLigustrum lucidum W.T. Aiton is a traditional Chinese medicine that has long been used with high hepatoprotective therapeutic and condition value. Specnuezhenide (SP), the standard prominent secoiridoid compound of Fructus Ligustri Lucidi may ameliorate hepatic inflammation in chronic liver diseases. Aim of the studyRegulating inflammation through SIRT6-P2X7R axis has caused the emergence of novel molecular mechanism strategies for reversing hepatic fibrosis. This study focused on the mechanism of SP in modulating the liver inflammatory microenvironment in hepatic fibrosis. Materials and methodsC57BL/6 mice with hepatic fibrosis were stimulated with thioacetamide (TAA) prior to administration of SP. Hepatic stellate cells (HSCs) or normal mouse primary hepatocytes were exposed to transforming growth factor-β (TGF-β) treatment. Meanwhile, normal mouse bone marrow-derived macrophages (BMDMs) were treated with lipopolysaccharide/adenosine triphosphate (LPS/ATP), aiming to obtain the conditioned medium. HSCs and hepatocytes were transfected with SIRT6 knockdown vector (siRNA-SIRT6) to estimate the impact of SP on the SIRT6-P2X7R/NLRP3 signaling pathway. ResultsSP suppressed the HSCs extracellular matrix (ECM) deposition as well as pro-inflammatory cytokine levels induced by the medium of BMDMs or TGF-β. In addition, SP also significantly up-regulated SIRT6, inhibited P2X7R-NLRP3 inflammasome in HSCs and hepatocytes, and functioned as MDL-800 (a SIRT6 agonist). SP reduced the hepatocytes pyroptosis and further prevented the occurrence of inflammatory response in the liver. SP could inhibit the activation of BMDMs and impede IL-1β and IL-18 from entering extracellular regions. Moreover, deficiency of SIRT6 in HSCs or hepatocytes reduced SP's regulation of P2X7R suppression. For TAA-treated mice, SP mitigated histopathological changes, ECM accumulation, EMT process, and NETs formation in hepatic fibrosis. ConclusionsTherefore, SP decreased inflammatory response via SIRT6-P2X7R/NLRP3 pathway and suppressed fibrillogenesis. These findings supported SP as the novel candidate to treat hepatic fibrosis.

Abstract Tu095: Cycloastragenol Alleviates Cardiac Fibrosis through Inhibiting Pyroptosis Activated by NLRP3 Inflammasome

Cardiac fibrosis is cardiac interstitial remodeling characterized by an enhanced extracellular matrix deposition. Acute sympathetic stress causes cardiac cells to immediately undergo pyroptosis, which induces cardiac inflammation and damage, and ultimately results in cardiac fibrosis. Our previous study has demonstrated the inhibitory effects of cycloastragenol (CAG), an active form of astragaloside IV isolated from Astragalus membranaceus, on isoproterenol (ISO)-induced cardiac fibrosis through blocking the NLRP3 signaling pathway. It is yet unknown how CAG affects pyroptosis of cardiac cells and whether its ability to prevent cardiac fibrosis coincides with this process. In this study, 5 mg/kg ISO was subcutaneously injected into wild-type (WT), NLRP3 knockout (KO), and GSDMD KO mice for 7 days to induce cardiac fibrosis. CAG (125 mg/kg/d) was administrated to the mice intragastrically at the start of the ISO injection. Primary cardiomyocytes and cardiac fibroblasts were isolated from neonatal rat hearts and treated with 10 μM ISO either with or without CAG. The results show that CAG alleviates cardiac fibrosis in WT mice, while lost this efficacy in NLRP3 KO mice. GSDMD KO mice do not develop ISO-induced cardiac fibrosis, indicating the key role of pyroptosis in cardiac fibrosis. Pyroptosis mainly occurs in mouse hearts during the initial stages of ISO induction (1 and 24 hours after ISO injection), and CAG significantly reduces pyroptosis of heart cells in WT mice, while CAG is unable to prevent pyroptosis in NLRP3 KO mouse hearts. The TGF-/Smads signaling pathway is also inhibited by CAG in WT mice but not in NLRP3 KO mice. Additionally, CAG prevents the in vitro pyroptosis of cardiomyocytes induced by ISO directly and cardiac fibroblasts caused by LPS+ATP. These results suggest that the principal mechanism of the anti-cardiac fibrosis effect of CAG mainly depends on its inhibition of pyroptosis mediated by NLRP3 inflammasome.

The pivotal role of microglia in injury and the prognosis of subarachnoid hemorrhage.

Subarachnoid hemorrhage leads to a series of pathological changes, including vascular spasm, cellular apoptosis, blood-brain barrier damage, cerebral edema, and white matter injury. Microglia, which are the key immune cells in the central nervous system, maintain homeostasis in the neural environment, support neurons, mediate apoptosis, participate in immune regulation, and have neuroprotective effects. Increasing evidence has shown that microglia play a pivotal role in the pathogenesis of subarachnoid hemorrhage and affect the process of injury and the prognosis of subarachnoid hemorrhage. Moreover, microglia play certain neuroprotective roles in the recovery phase of subarachnoid hemorrhage. Several approaches aimed at modulating microglia function are believed to attenuate subarachnoid hemorrhage injury. This provides new targets and ideas for the treatment of subarachnoid hemorrhage. However, an in-depth and comprehensive summary of the role of microglia after subarachnoid hemorrhage is still lacking. This review describes the activation of microglia after subarachnoid hemorrhage and their roles in the pathological processes of vasospasm, neuroinflammation, neuronal apoptosis, blood-brain barrier disruption, cerebral edema, and cerebral white matter lesions. It also discusses the neuroprotective roles of microglia during recovery from subarachnoid hemorrhage and therapeutic advances aimed at modulating microglial function after subarachnoid hemorrhage. Currently, microglia in subarachnoid hemorrhage are targeted with TLR inhibitors, nuclear factor-κB and STAT3 pathway inhibitors, glycine/tyrosine kinases, NLRP3 signaling pathway inhibitors, Gasdermin D inhibitors, vincristine receptor α receptor agonists, ferroptosis inhibitors, genetic modification techniques, stem cell therapies, and traditional Chinese medicine. However, most of these are still being evaluated at the laboratory stage. More clinical studies and data on subarachnoid hemorrhage are required to improve the treatment of subarachnoid hemorrhage.

The effect of ethanol extracts of loulu flower on LPS-induced acute lung injury in mice

Ethnopharmacological relevanceIn Mongolian medicine, Loulu flower (LLF), the dried inflorescence of Rhaponticum uniflorum (L.) DC. from the Compositae family, has been used to clear heat and relieve toxicity for millennia, particularly in the treatment of pneumonia. Aim of this studyTo reveal the effects of LLF on mice with lipopolysaccharide (LPS)-stimulated acute lung injury (ALI) and elucidate the underlying mechanisms. Materials and methodsALI was established in BALB/c mice via nasal drops administration of LPS (5 mg/kg). The mice were then orally administrated with various doses of LLF extracts and the positive drug dexamethasone (DEX, 5 mg/kg), once daily for seven consecutive days. Last day, after being stimulated with LPS for 6h, the mice were closed dislocation of cervical vertebra, the serum, bronchus alveolar lavage fluid (BALF) and lung tissue were put into the EP tube and stored at −80 °C for further analysis. The changes of histopathology were tested by hematoxylin and eosin stain (H&E), the levels of, IL-1β, IL-18, TNF-α and IL-4 in BALF and serum were measured by ELISA. The pathways related to the treatment of ALI were predicted by network pharmacology. The expression levels of TLR4/NF-κB and NLRP3 signaling pathway-associated proteins, COX-2 and ERK were tested by western blotting. The levels of P65 and NLRP3 in lung tissues were determined by immunofluorescence analysis. ResultsLLF total extract and the extract parts could alleviate the inflammatory cell infiltration, thicken the alveolar walls in lung tissues, reduce the levels of IL-18, IL-1β in BALF, the TNF-α in both BALF and serum, meantime enhance the level of IL-4 in BALF and serum in mice with LPS-induced ALI. Our network pharmacology and comprehensive gene ontology analyses revealed the active constituents of LLF and the pathways, including TLR4/NF-κB, NLRP3 and MAPK signaling pathways, which play significant roles in ALI. Furthermore, both the total extract and its extraction portions suppressed the expressions of proteins related with the COX-2, p-ERK and TLR4/NF-κB signaling pathway (TLR4, p-IκB, p-p65), as well as the NLRP3 signaling pathway (NLRP3, cleaved caspase-1, caspase-1, IL-1β). ConclusionLLF could improve the pathological changes and reducing inflammatory reactions in mice induced by LPS. The mechanism may be related to the modulation of the TLR4/NLRP3 signaling pathways.

Polygala tenuifolia willd. Extract alleviates LPS-induced acute lung injury in rats via TLR4/NF-κB pathway and NLRP3 inflammasome suppression

BackgroundAcute lung injury (ALI) has received considerable attention in the field of critical care as it can lead to high mortality rates. Polygala tenuifolia, a traditional Chinese medicine with strong expectorant properties, can be used to treat pneumonia. Owing to the complexity of its composition, the main active ingredient is not yet known. Thus, there is a need to identify its constituent compounds and mechanism of action in the treatment of ALI using advanced technological means. PurposeWe investigated the anti-inflammatory mechanism and constituent compounds with regard to the effect of P. tenuifolia Willd. extract (EPT) in lipopolysaccharide (LPS)-induced ALI in vivo and in vitro. MethodsThe UHPLC-Q-Exactive Orbitrap MS technology was used to investigate the chemical profile of EPT. Network pharmacology was used to predict the targets and pathways of action of EPT in ALI, and molecular docking was used to validate the binding of polygalacic acid to Toll-like receptor (TLR) 4. The main compounds were determined using LC-MS. A rat model of LPS-induced ALI was established, and THP-1 cells were stimulated with LPS and adenosine triphosphate (ATP) to construct an in vitro model. Pathological changes were observed using hematoxylin and eosin staining, Wright-Giemsa staining, and immunohistochemistry. The expression of inflammatory factors (NE, MPO, Ly-6 G, TNF-α, IL-1β, IL-6, and iNOS) was determined using enzyme-linked immunosorbent assay, real-time fluorescence quantitative polymerase chain reaction, and western blotting. The LPS + ATP-induced inflammation model in THP-1 cells was used to verify the in vivo experimental results. ResultsNinety-nine compounds were identified or tentatively deduced from EPT. Using network pharmacology, we found that TLR4/NF-κB may be a relevant pathway for the prevention and treatment of ALI by EPT. Polygalacic acid in EPT may be a potential active ingredient. EPT could alleviate LPS-induced histopathological lung damage and reduce the wet/dry lung weight ratio in the rat model of ALI. Moreover, EPT decreased the white blood cell and neutrophil counts in the bronchoalveolar lavage fluid and decreased the expression of genes and proteins of relevant inflammatory factors (NE, MPO, Ly-6 G, TNF-α, IL-1β, IL-6, and iNOS) in lung tissues. It also increased the expression of endothelial-type nitric oxide synthase expression. Western blotting confirmed that EPT may affect TLR4/NF-κB and NLRP3 signaling pathways in vivo. Similar results were obtained in THP-1 cells. ConclusionEPT reduced the release of inflammatory factors by affecting TLR4/NF-κB and NLRP3 signaling pathways, thereby attenuating the inflammatory response of ALI. Polygalacic acid is the likely compounds responsible for these effects.

Disulfiram downregulates ferredoxin 1 to maintain copper homeostasis and inhibit inflammation in cerebral ischemia/reperfusion injury

In the current study, we aimed to investigate whether disulfiram (DSF) exerts a neuroprotective role in cerebral ischemiareperfusion(CI-RI) injury by modulating ferredoxin 1 (FDX1) to regulate copper ion (Cu) levels and inhibiting inflammatoryresponses. To simulate CI-RI, a transient middle cerebral artery occlusion (tMCAO) model in C57/BL6 mice was employed. Mice were administered with or without DSF before and after tMCAO. Changes in infarct volume after tMCAO were observed using TTC staining. Nissl staining and hematoxylin–eosin (he) staining were used to observe the morphological changes of nerve cells at the microscopic level. The inhibitory effect of DSF on initial inflammation was verified by TUNEL assay, apoptosis-related protein detection and iron concentration detection. FDX1 is the main regulatory protein of copper death, and the occurrence of copper death will lead to the increase of HSP70 stress and inflammatory response. Cuproptosis-related proteins and downstream inflammatory factors were detected by western blotting, immunofluorescence staining, and immunohistochemistry. The content of copper ions was detected using a specific kit, while electron microscopy was employed to examine mitochondrial changes. We found that DSF reduced the cerebral infarction volume, regulated the expression of cuproptosis-related proteins, and modulated copper content through down regulation of FDX1 expression. Moreover, DSF inhibited the HSP70/TLR-4/NLRP3 signaling pathway. Collectively, DSF could regulate Cu homeostasis by inhibiting FDX1, acting on the HSP70/TLR4/NLRP3 pathway to alleviate CI/RI. Accordingly, DSF could mitigate inflammatory responses and safeguard mitochondrial integrity, yielding novel therapeutic targets and mechanisms for the clinical management of ischemia–reperfusion injury.

Gentiopicroside improves NASH and liver fibrosis by suppressing TLR4 and NLRP3 signaling pathways

BackgroundNon-alcoholic steatohepatitis (NASH) and liver fibrosis are progressive conditions associated with non-alcoholic fatty liver disease (NAFLD), characterized by hepatocyte pyroptosis and hepatic stellate cell (HSC) activation. Gentiopicroside (GPS) has emerged as a potential treatment for NASH, yet its underlying mechanism remains unclear. AimTo confirm that GPS can improve NASH and liver fibrosis by blocking the NLRP3 signaling pathway Study designInitially, different animal models were used to study the effects and mechanisms of GPS on NASH and fibrosis. Subsequent in vitro experiments utilized co-cultures and other techniques to delve deeper into its mechanism, followed by validation of the findings in mouse liver tissues. MethodsC57BL/6 mice were fed high-fat, high-cholesterol (HFHC), or methionine-choline-deficient (MCD) diets to induce NASH and fibrosis. RAW264.7 cells and born marrow bone marrow-derived macrophages (BMDMs) were stimulated with LPS and ATP to induce inflammation, then co-cultured with primary hepatocytes and HSCs, treated with GPS, and its efficacy and mechanism were analyzed. ResultsIn vivo, GPS alleviated NASH and liver fibrosis by inhibiting the NLRP3 pathway. In vitro, GPS attenuated inflammation induced by BMDMs by inhibiting TLR4 and NLRP3 signaling pathways, and Co-culture studies suggested that GPS reduced hepatocyte pyroptosis and HSC activation, which was also confirmed in liver tissues ConclusionGPS improves NASH and liver fibrosis by inhibiting the TLR4 and NLRP3 signaling pathways. The specific mechanism may be related to the suppression of macrophage-mediated inflammatory responses, thereby reducing hepatocyte pyroptosis and HSC activation.

Role of IRE1α/XBP1/CHOP/NLRP3 Signalling Pathway in Neonicotinoid Imidacloprid-Induced Pancreatic Dysfunction in Rats and Antagonism of Lycopene: In Vivo and Molecular Docking Simulation Approaches.

Imidacloprid (IMI) is a commonly used new-generation pesticide that has numerous harmful effects on non-targeted organisms, including animals. This study analysed both the adverse effects on the pancreas following oral consumption of imidacloprid neonicotinoids (45 mg/kg daily for 30 days) and the potential protective effects of lycopene (LYC) administration (10 mg/kg/day for 30 days) with IMI exposure in male Sprague-Dawley rats. The apoptotic, pyroptotic, inflammatory, oxidative stress, and endoplasmic reticulum stress biomarkers were evaluated, along with the histopathological alterations. Upon IMI administration, noticeable changes were observed in pancreatic histopathology. Additionally, elevated oxidative/endoplasmic reticulum-associated stress biomarkers, inflammatory, pyroptotic, and apoptotic biomarkers were also observed following IMI administration. LYC effectively reversed these alterations by reducing oxidative stress markers (e.g., MDA) and enhancing antioxidant enzymes (SOD, CAT). It downregulated ER stress markers (IRE1α, XBP1, CHOP), decreased pro-inflammatory cytokines (TNF-α, IL-1β), and suppressed pyroptotic (NLRP3, caspase-1) along with apoptotic markers (Bax, cleaved caspase-3). It also improved the histopathological and ultrastructure alterations brought on by IMI toxicity.