Search

Chronic and excessive alcohol consumption leads to liver toxicity. There is a need to investigate effective therapeutic strategies to alleviate alcohol-induced liver injury, which remains the leading cause of liver-related morbidity and mortality worldwide. Therefore here, we looked into and evaluated how ethanol-induced hepatotoxicity was affected by coenzyme Q10 (CoQ10) and its analog, idebenone (IDE), on the NLRP3/caspase-1/IL-1 pathway. Hepatotoxicity induced in rats through the oral administration of gradually increasing dosages of ethanol (from 2 to 6 g/kg/day) over 30 days and the effect of CoQ10 (10 or 20 mg/kg) and IDE (50 or 100 mg/kg) were evaluated. Serum hepatotoxicity markers (ALT, AST, GGT, ALP, and TBIL), tissue oxidative stress markers and the mRNA expressions of IL-1β, IL-18, TGF-β, NF-κB, NLRP3, and caspase-1 were evaluated. Masson's trichrome staining was also used to visualize fibrosis in the liver tissue. The results indicated that ethanol exposure led to hepatotoxicity as well as considerable NLRP3/caspase-1/IL-1β pathway activation. Moreover, CoQ10 or IDE treatment reduced measured parameters in a dosage-dependent manner. Thus, by inhibiting the NLRP3/caspase-1/IL-1 pathway, CoQ10 and IDE can prevent the hepatotoxicity caused by ethanol, although CoQ10 is more effective than IDE. This study will provide insight into new therapeutic avenues that take advantage of the anti-inflammatory and antioxidant properties of CoQ10 and IDE in ethanol-induced liver diseases. [ABSTRACT FROM AUTHOR]

The inflammasome is a multiprotein complex involved in innate immunity that mediates the inflammatory response leading to pyroptosis, which is a lytic, inflammatory form of cell death. There is accumulating evidence that nucleotide-binding domain and leucine-rich repeat pyrin domain containing 3 (NLRP3) inflammasome-mediated microglial pyroptosis and NLRP1 inflammasome-mediated neuronal pyroptosis in the brain are closely associated with the pathogenesis of Alzheimer's disease. In this review, we summarize the possible pathogenic mechanisms of Alzheimer's disease, focusing on neuroinflammation. We also describe the structures of NLRP3 and NLRP1 and the role their activation plays in Alzheimer's disease. Finally, we examine the neuroprotective activity of small-molecule inhibitors, endogenous inhibitor proteins, microRNAs, and natural bioactive molecules that target NLRP3 and NLRP1, based on the rationale that inhibiting NLRP3 and NLRP1 inflammasome-mediated pyroptosis can be an effective therapeutic strategy for Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Introduction: Inflammation and cell death play an important role in the pathogenesis of diabetic retinopathy. Previously we observed sustained activation of pro-inflammatory caspase-1 in retinas of diabetic animals and patients. In this study, we aimed to look at mechanisms underlying chronic caspase-1 activation in vitro and in vivo. Methods: Non-diabetic and diabetic wild type and IL-1 receptor (IL-1R1) knockout mice were used for in vivo experiments. Diabetes was induced using STZ (streptozotocin). Human Müller cells were used for in vitro studies. Cells were treated with either 5 mM or 25 mM glucose or interleukin-1beta (IL-1β) in the presence or absence of IL-1 receptor antagonist (IL-1ra) or siRNA against RIP2 (receptor interacting protein-2) for up to 96 h. Outcome measurements to assess Müller cell functions included measurements of caspase-1 activity using a fluorescence peptide substrate, production of IL-1β by Elisa, and cell death using trypan blue exclusion assays. Results: Our in vivo results demonstrate that caspase-1 activation progresses from an IL-1R1 independent mechanism at 10 weeks of diabetes to an IL-1R1 dependent mechanism at 20 weeks indicating that feedback through IL-1R1 is crucial for sustained caspase-1 activity in retinas of mice. A similar hyperglycemia-mediated caspase-1/IL-1β/IL-1R1 feedback signaling was detected in vitro in human Müller cells which was prevented by treatment with IL-1ra. Our data also indicate that hyperglycemia induces caspase-1 activation initially but IL-1β sustains caspase-1 activation via caspase-1/IL-1β/ IL-1R1 feedback and we identified RIP2 as mediator for both hyperglycemia- and IL-1β-induced caspase-1 activation. Activation of caspase-1/IL-1β/IL-1R1 feedback signaling caused Müller cell death which was prevented by RIP2 knockdown. Discussion: We conclude that any intervention in caspase-1/IL-1β/IL-1R1 feedback signaling presents novel therapeutic options for the treatment of diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Summary The NLRP3 inflammasome is a multiprotein complex that upon activation by the innate immune system drives a broad inflammatory response. The primary initial mediators of this response are pro‐IL‐1β and pro‐IL‐18, both of which are in an inactive form. Formation and activation of the NLRP3 inflammasome activates caspase‐1, which cleaves pro‐IL‐1β and pro‐IL‐18 and triggers the formation of gasdermin D pores. Gasdermin D pores allow for the secretion of active IL‐1β and IL‐18 initiating the organism‐wide inflammatory response. The NLRP3 inflammasome response can be beneficial to the host; however, if the NLRP3 inflammasome is inappropriately activated it can lead to significant pathology. While the primary components of the NLRP3 inflammasome are known, the precise details of assembly and activation are less well defined and conflicting. Here, we discuss several of the proposed pathways of activation of the NLRP3 inflammasome. We examine the role of subcellular localization and the reciprocal regulation of the NLRP3 inflammasome by autophagy. We focus on the roles of mitochondria and mitophagy in activating and regulating the NLRP3 inflammasome. Finally, we detail the impact of pathologic NLRP3 responses in the development and manifestations of pulmonary disease. [ABSTRACT FROM AUTHOR]

AbstractPurposeMethodsResultsConclusionThe purpose of this study was to investigate the role and mechanism of caspase-8 in the development of choroidal neovascularization induced by age-related macular degeneration, with the aim of identifying a potential therapeutic target for neovascular age-related macular degeneration.Mouse models of laser photocoagulation-induced choroidal neovascularization and hypoxic human choroidal endothelial cells were utilized to examine the involvement of caspase-8 in choroidal neovascularization development. The toll-like receptor 4/TIR domain-containing adaptor molecule 1/caspase-8 pathway was explored in hypoxic human choroidal endothelial cells to elucidate its contribution to pathological angiogenesis. Various experimental techniques, including inhibition assays and immunoblotting analysis, were employed to assess the effects and mechanisms of caspase-8 activation.Inhibition of caspase-8 demonstrated attenuated choroidal neovascularization development in mice subjected to laser photocoagulation. Activation of the toll-like receptor 4/TIR domain-containing adaptor molecule 1/caspase-8 pathway was observed in hypoxic human choroidal endothelial cells. Upon activation by the toll-like receptor 4/TIR domain-containing adaptor molecule 1 axis, caspase-8 directly cleaved caspase-1, leading to the cleavage of interleukin-1β and interleukin-18 by caspase-1. Consequently, activation of interleukin-1β and interleukin-18 through the toll-like receptor 4/TIR domain-containing adaptor molecule 1/caspase-8/caspase-1 pathway promoted the proliferative, migratory, and tube-forming abilities of hypoxic human choroidal endothelial cells.The findings of this study indicate that caspase-8 plays a crucial role in promoting choroidal neovascularization by activating interleukin-1β and interleukin-18 through the toll-like receptor 4/TIR domain-containing adaptor molecule 1/caspase-8/caspase-1 pathway in choroidal endothelial cells. Therefore, targeting caspase-8 may hold promise as a therapeutic approach for neovascular age-related macular degeneration. [ABSTRACT FROM AUTHOR]

Despite significant advances in prenatal medicine, spontaneous miscarriage remains one of the most common and serious pregnancy complications, affecting an increasing number of women. Since many aspects of the pathogenesis of spontaneous miscarriage remain unexplained, the aim of this study has been to assess the involvement of the NLRP3 inflammasome as a potential causative factor. The concentrations of NLRP3, IL-1β, IL-18, and cytochrome C in the serum of patients after miscarriage were measured by means of the immunoenzymatic method. In the placental tissue, the expression of NLRP3, IL-1β, IL-18, and Caspase-1 as well as that of the classical apoptosis biomarkers Fas, FasL, Bcl-2, and Ca was evaluated by means of immunohistochemistry techniques. Additionally, in whole blood, the concentrations of elements crucial for pregnancy progression, such as Ca, K, Mg, and Na, were examined by means of the ICP-OES method. Significantly higher concentrations of NLRP3 and IL-18 were demonstrated in the serum of patients with miscarriage as compared to the control group. In the placental tissue samples, a higher expression of IL-1β, IL-18, and Caspase-1 proteins was noted in women who had experienced miscarriage as compared to the control group. At the same time, a significantly lower expression of FasL and Bcl-2 proteins as well as Ca deposits was observed in women after miscarriage as compared to those with a normal pregnancy outcome. Significantly lower concentrations of Ca and K were recorded in the blood of patients with spontaneous miscarriage as compared to pregnant women. The analysis of the results x indicated a greater involvement of the inflammasome in women with spontaneous miscarriage associated with oxidative–antioxidative imbalance than in the case of miscarriage related to NET formation. Our research has provided evidence for the involvement of the inflammasome in the process of spontaneous miscarriage and identifies a new direction for diagnostics that includes NLRP3 as a preventive element in prenatal care, particularly in light of the steadily declining number of pregnancies and the increasing number of reproductive failures. [ABSTRACT FROM AUTHOR]

Summary Inflammasomes are multi‐protein complexes that assemble within the cytoplasm of mammalian cells in response to pathogen‐associated molecular patterns (PAMPs) or damage‐associated molecular patterns (DAMPs), driving the secretion of the pro‐inflammatory cytokines IL‐1β and IL‐18, and pyroptosis. The best‐characterized inflammasome complexes are the NLRP3, NAIP‐NLRC4, NLRP1, AIM2, and Pyrin canonical caspase‐1‐containing inflammasomes, and the caspase‐11 non‐canonical inflammasome. Newer inflammasome sensor proteins have been identified, including NLRP6, NLRP7, NLRP9, NLRP10, NLRP11, NLRP12, CARD8, and MxA. These inflammasome sensors can sense PAMPs from bacteria, viruses and protozoa, or DAMPs in the form of mitochondrial damage, ROS, stress and heme. The mechanisms of action, physiological relevance, consequences in human diseases, and avenues for therapeutic intervention for these novel inflammasomes are beginning to be realized. Here, we discuss these emerging inflammasome complexes and their putative activation mechanisms, molecular and signaling pathways, and physiological roles in health and disease. [ABSTRACT FROM AUTHOR]

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 (IC 50) 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. [Display omitted] • NLRP3 signaling pathway is a promising therapeutic target for the prevention of drug toxicity. • NLRP3 inflammasome activation might contribute to the hepatotoxicity effects of ponatinib and bosutinib. • Oxidative stress might be initiating event of ponatinib and bosutinib-induced NLRP3 inflammasome activation. [ABSTRACT FROM AUTHOR]

Background/Objectives: Isatidis Folium (IF) has been used in traditional medicine for various ailments, and recent research highlights its anti-inflammatory, antiviral, and detoxifying properties. This study investigated the anti-inflammatory effects of a hydroethanolic extract of IF (EIF) on inflammasomes and colitis. Methods: Dextran sulfate sodium (DSS)-induced colitis model C57BL/6 mice were treated with DSS, mesalamine, or EIF (200 mg/kg). Parameters such as daily disease activity index (DAI), spleen weight, colon length, and histopathology were evaluated. Intestinal fibrosis, mucin, and tight junction proteins were assessed using Masson's trichrome, periodic acid–Schiff, and immunohistochemistry staining. RAW264.7 and J774a.1 macrophages were treated with EIF and lipopolysaccharide, with cell viability assessed via the cell counting kit-8 assay, nitric oxide (NO) production with Griess reagent, and cytokine levels with the enzyme-linked immunosorbent assay. NF-κB inhibition was analyzed using the luciferase assay, and phytochemical analysis was performed using UPLC-MS/MS. Results: EIF mitigated weight loss, reduced DAI scores, prevented colon shortening, and attenuated mucosal damage, fibrosis, and goblet cell loss while enhancing the tight junction protein occludin. The anti-inflammatory effects of EIF in RAW264.7 cells included reduced NO production, pro-inflammatory cytokines, and NF-κB activity, along with inhibition of NLRP3 inflammasome responses in J774a.1 cells. The key constituents identified were tryptanthrin, indigo, and indirubin. Conclusions: Animal studies demonstrated the efficacy of EIF in alleviating colitis, suggesting its potential for treating inflammatory diseases. [ABSTRACT FROM AUTHOR]

Cigarette smoke (CS) is a major risk factor for chronic lung diseases and promotes activation of pattern recognition receptors in the bronchial epithelium. NOD‐like receptor family, pyrin domain‐containing 3 (NLRP3) is a pattern recognition receptor whose activation leads to caspase‐1 cleavage, maturation/release of IL‐1β and IL‐18, and eventually pyroptosis. Whether the NLRP3 inflammasome participates in CS‐induced inflammation in bronchial epithelial cells is still unclear. Herein, we evaluated the involvement of NLRP3 in CS‐induced inflammatory responses in human primary bronchial epithelial cells. To this purpose, human primary bronchial epithelial cells were stimulated with CS extracts (CSE) and lytic cell death, caspase activation (‐1, ‐8, ‐3/7), cytokine release (IL‐1β, IL‐18, and IL‐8), NLRP3, pro‐IL‐1β/pro‐IL‐18 mRNA, and protein expression were measured. The impact of inhibitors of NLRP3 (MCC950), caspases, and the effect of the antioxidant N‐acetyl cysteine were evaluated. We found that CSE increased pro‐IL‐1β expression and induced activation of caspase‐1 and release of IL‐1β and IL‐18. These events were independent of NLRP3 and we found that NLRP3 was not expressed. N‐acetyl cysteine reverted CSE‐induced caspase‐1 activation. Overall, our findings support that the bronchial epithelium may play a central role in the release of IL‐1 family cytokines independently of NLRP3 in the lungs of smokers. [ABSTRACT FROM AUTHOR]

Background: Retinal ischemia/reperfusion (IR) injury is a common pathological process in many ophthalmic diseases. Interleukin-1β (IL-1β) is an important inflammatory factor involved in the pathology of retinal IR injury, but the mechanism by which IL-1β is regulated in such injury remains unclear. Caspase-11 non-canonical inflammasomes can regulate the synthesis and secretion of IL-1β, but its role in retinal IR injury has not been elucidated. This study aimed to evaluate the role of caspase-11 non-canonical inflammasomes in retinal IR injury. Methods: Retinal IR injury was induced in C57BL/6J mice by increasing the intraocular pressure to 110 mmHg for 60 min. The post-injury changes in retinal morphology and function and in IL-1β expression were compared between caspase-11 gene knockout (caspase-11−/−) mice and wild-type (WT) mice. Morphological and functional changes were evaluated using hematoxylin–eosin staining and retinal whole mount staining and using electroretinography (ERG), respectively. IL-1β expression in the retina was measured using enzyme-linked immunosorbent assay (ELISA). The levels of caspase-11-related protein were measured using western blot analysis. The location of caspase-11 in the retina was determined via immunofluorescence staining. Mouse type I astrocytes C8-D1A cells were used to validate the effects of caspase-11 simulation via hypoxia in vitro. Small-interfering RNA targeting caspase-11 was constructed. Cell viability was evaluated using the MTT assay. IL-1β expression in supernatant and cell lysate was measured using ELISA. The levels of caspase-11-related protein were measured using western blot analysis. Results: Retinal ganglion cell death and retinal edema were more ameliorated, and the ERG b-wave amplitude was better after retinal IR injury in caspase-11−/− mice than in WT mice. Further, caspase-11−/− mice showed lower protein expressions of IL-1β, cleaved caspase-1, and gasdermin D (GSDMD) in the retina after retinal IR injury. Caspase-11 protein was expressed in retinal glial cells, and caspase-11 knockdown played a protective role against hypoxia in C8-D1A cells. The expression levels of IL-1β, cleaved caspase-1, and GSDMD were inhibited after hypoxia in the si-caspase-11 constructed cells. Conclusions: Retinal IR injury activates caspase-11 non-canonical inflammasomes in glial cells of the retina. This results in increased protein levels of GSDMD and IL-1β and leads to damage in the inner layer of the retina. [ABSTRACT FROM AUTHOR]

James V Gruber,1 Nicole Terpak,2 Sebastien Massard,2 Xiang Chen,2 Yurah Kim2 1Research, Vantage, Fairfield, NJ, USA; 2Research, Vantage, Warren, NJ, USACorrespondence: James V Gruber, Email vincent.gruber@vantagegrp.comIntroduction: It is well established that Cutibacterium acnes (C. acnes) is a common skin commensal microorganism that has been linked to acne. In acne flare-ups, C. acnes can be found in abundant levels within the inflammatory lesions (called comedones) associated with the skin disease. Recently, it was reported that 3D reconstructed human epidermis (RHE) treated with viable cultures of C. acnes can elicit β-defensin antimicrobial peptide responses in the skin and can weaken the skin barrier of the RHE after three days of exposure to C. acnes.Methods: Employing a modification of this in vitro assay, RHE was pretreated with C. acnes for 48 hours, then further treated with a mixture of water-soluble polysaccharides (STRATAPHIX™ POLY, “Polysaccharide Blend”) previously shown to reduce inflammasome-mediated inflammatory responses in normal human epidermal keratinocytes (NHEK). Two inflammasome-mediated inflammation markers were tested, including caspase-1, a potent protease enzyme activated by NOD-like receptor protein (NLRP)-induced inflammasome activation, and interleukin-1β (IL-1β), a cytokine which is activated from inactive pro-IL-1β by caspase-1.Results: The treatment of the RHE tissues with C. acnes for 48 hours elicited an inflammatory response measured with both markers compared against untreated tissues. Treatment of the tissues with 1% and 2% salicylic acid for 24 hours after C. acnes treatment increased the inflammatory response measured with both markers. Application of the water-soluble polysaccharides in combination with 1% and 2% of salicylic acid significantly reduces expression of both active caspase-1 and IL-1β compared against the tissues treated with C. acnes and salicylic acid alone.Discussion: The results lend further support to previously reported work which was done on NHEKs treated with ultraviolet B (UVB) light and adenosine triphosphate (ATP) and demonstrate that the same mixture of polysaccharides can have a modulating effect against bacterial and chemical induced inflammation in RHE.Keywords: Cutibacterium acnes, In vitro, tissues, inflammation, caspase-1, IL-1β, topical

Abdullah Al Mamun,1,2 Peiwu Geng,1 Shuanghu Wang,1 Chuxiao Shao1 1Key Laboratory of Joint Diagnosis and Treatment of Chronic Liver Disease and Liver Cancer of Lishui, The Lishui Hospital of Wenzhou Medical University, The First Affiliated Hospital of Lishui University, Lishui People’s Hospital, Lishui, Zhejiang, 323000, People’s Republic of China; 2Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of ChinaCorrespondence: Chuxiao Shao; Shuanghu Wang, Key Laboratory of Joint Diagnosis and Treatment of Chronic Liver Disease and Liver Cancer of Lishui, the Lishui Hospital of Wenzhou Medical University, the First Affiliated Hospital of Lishui University, Lishui People’s Hospital, Lishui, Zhejiang, 323000, People’s Republic of China, Email scx1818@126.com; wangshuanghu@lsu.edu.cnAbstract: Pyroptosis is an inflammatory cell death induced by inflammasomes that release several pro-inflammatory mediators such as interleukin-18 (IL-18) and interleukin-1β (IL-1β). Pyroptosis, a type of programmed cell death, has recently received increased interest both as a therapeutic and immunological mechanism. Numerous studies have provided substantial evidence supporting the involvement of inflammasomes and pyroptosis in a variety of pathological conditions including cancers, nerve damage, inflammatory diseases and metabolic conditions. Researchers have demonstrated that dysregulation of pyroptosis and inflammasomes contribute to the progression of endometriosis and gynecological malignancies. Current research also indicates that inflammasome and pyroptosis-dependent signaling pathways may further induce the progression of endometrial cancer (EC). More specifically, dysregulation of NLR family pyrin domain 3 (NLRP3) and caspase-1-dependent pyroptosis play a contributory role in the pathogenesis and development of EC. Therefore, pyroptosis-regulated protein gasdermin D (GSDMD) may be an independent prognostic biomarker for the detection of EC. This review presents the molecular mechanisms of pyroptosis-dependent signaling pathways and their contributory role and function in advancing EC. Moreover, this review offers new insights into potential future applications and innovative approaches in utilizing pyroptosis to develop effective anti-cancer therapies. Keywords: endometrial cancer, pyroptosis, NLRP3, caspase-1, GSDMD, IL-1β, IL-18

Abstract Background Retinal ischemia/reperfusion (IR) injury is a common pathological process in many ophthalmic diseases. Interleukin-1β (IL-1β) is an important inflammatory factor involved in the pathology of retinal IR injury, but the mechanism by which IL-1β is regulated in such injury remains unclear. Caspase-11 non-canonical inflammasomes can regulate the synthesis and secretion of IL-1β, but its role in retinal IR injury has not been elucidated. This study aimed to evaluate the role of caspase-11 non-canonical inflammasomes in retinal IR injury. Methods Retinal IR injury was induced in C57BL/6J mice by increasing the intraocular pressure to 110 mmHg for 60 min. The post-injury changes in retinal morphology and function and in IL-1β expression were compared between caspase-11 gene knockout (caspase-11−/−) mice and wild-type (WT) mice. Morphological and functional changes were evaluated using hematoxylin–eosin staining and retinal whole mount staining and using electroretinography (ERG), respectively. IL-1β expression in the retina was measured using enzyme-linked immunosorbent assay (ELISA). The levels of caspase-11-related protein were measured using western blot analysis. The location of caspase-11 in the retina was determined via immunofluorescence staining. Mouse type I astrocytes C8-D1A cells were used to validate the effects of caspase-11 simulation via hypoxia in vitro. Small-interfering RNA targeting caspase-11 was constructed. Cell viability was evaluated using the MTT assay. IL-1β expression in supernatant and cell lysate was measured using ELISA. The levels of caspase-11-related protein were measured using western blot analysis. Results Retinal ganglion cell death and retinal edema were more ameliorated, and the ERG b-wave amplitude was better after retinal IR injury in caspase-11−/− mice than in WT mice. Further, caspase-11−/− mice showed lower protein expressions of IL-1β, cleaved caspase-1, and gasdermin D (GSDMD) in the retina after retinal IR injury. Caspase-11 protein was expressed in retinal glial cells, and caspase-11 knockdown played a protective role against hypoxia in C8-D1A cells. The expression levels of IL-1β, cleaved caspase-1, and GSDMD were inhibited after hypoxia in the si-caspase-11 constructed cells. Conclusions Retinal IR injury activates caspase-11 non-canonical inflammasomes in glial cells of the retina. This results in increased protein levels of GSDMD and IL-1β and leads to damage in the inner layer of the retina.

BACKGROUND: It was found that moxibustion can inhibit the inflammatory factors in the serum of rats with cerebral ischemia/reperfusion injury, resist oxidative stress, inhibit cell apoptosis, and effectively reduce cerebral ischemia/reperfusion injury. OBJECTIVE: To observe the effects of different moxibustion intervention time on the expression levels of nucleotide binding oligomerization domain-like protein 3 inflammasome (NLRP3), cysteine aspartase (caspase-1), apoptosis-related speck-like protein, exfoliatin-D protein, interleukin-1β and interleukin-18 in rats with cerebral ischemia/reperfusion injury, and to explore its action mechanism. METHODS: SD rats were randomly divided into sham operation group (n=9) and operation group (n=36). The model of focal cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion in the operation group. After successful modeling, the rats in the operation group were further divided into model group, moxibustion 10-minute group, moxibustion 15-minute group and moxibustion 30-minute group, with 9 rats in each group. Rats in the moxibustion 10-minute, 15-minute and 30-minute groups were given moxibustion at “Baihui, Dazhui and Zusanli”, respectively, once a day for a total of 7 days. The neurological deficits of rats were evaluated by LONGA method. The cerebral infarction was observed by 2,3,5-triphenyltetrazolium chloride staining. The pathological changes of brain tissue were observed by hematoxylin-eosin staining. The contents of interleukin-1β and interleukin-18 in serum of rats in each group were detected by ELISA. Immunohistochemistry and western blot assay were used to detect the expression levels of NLRP3, caspase-1, apoptosis-related spot-like protein and gasdermin D in the ischemic cortex of rats in each group. RESULTS AND CONCLUSION: Compared with the sham operation group, the neurological deficit score of the model group was significantly increased (P < 0.01). Compared with the model group, the neurological deficit score of the moxibustion groups was significantly reduced (P < 0.01). Compared with the sham operation group, the infarct volume of the model group was significantly increased (P < 0.01). Compared with the model group, the infarct volume of the moxibustion groups was significantly reduced (P < 0.01); the infarct volume of the rats was smallest in the moxibustion 30-minute group (P < 0.05). Compared with the model group, the contents of inflammatory factors interleukin-1β and interleukin-18 in the serum of rats in the moxibustion groups were decreased (P < 0.01). Compared with the moxibustion 10-minute group, the contents of inflammatory factors in the serum of rats in the moxibustion 30-minute group were significantly decreased (P < 0.05). Compared with the model group, the expression of NLRP3, apoptosis-related spot-like protein, Caspase-1 and gasdermin D protein in the ischemic cortex of the moxibustion groups was significantly decreased (P < 0.01). Compared with the moxibustion 10-minute and 15-minute groups, the expression of protein in the moxibustion 30-minute group was significantly decreased (P < 0.05). It is concluded that moxibustion at Baihui, Dazhui and Zusanli can reduce cerebral ischemia/reperfusion injury, among which moxibustion for 30 minutes has the best effect, and its mechanism may be related to the inhibition of pyroptosis mediated by NLRP3/Caspase-1 pathway. [ABSTRACT FROM AUTHOR]

Abstract Cardiovascular complications pose a significant burden in type 2 diabetes mellitus (T2DM), driven by the intricate interplay of chronic hyperglycemia, insulin resistance, and lipid metabolism disturbances. Myocardial ischemia/reperfusion (MI/R) injury during cardiopulmonary bypass (CPB) exacerbates cardiac vulnerability. This study aims to probe the role of Caspase-1-dependent pyroptosis in global ischemia/reperfusion injury among T2DM rats undergoing CPB, elucidating the mechanisms underlying heightened myocardial injury in T2DM. This study established a rat model of T2DM and compared Mean arterial pressure (MAP), heart rate (HR), and hematocrit (Hct) between T2DM and normal rats. Myocardial cell morphology, infarction area, mitochondrial ROS and caspase-1 levels, NLRP3, pro-caspase-1, caspase-1 p10, GSDMD expressions, plasma CK-MB, cTnI, IL-1β, and IL-18 levels were assessed after reperfusion in both T2DM and normal rats. The role of Caspase-1-dependent pyroptosis in myocardial ischemia/reperfusion injury during CPB in T2DM rats was examined using the caspase-1 inhibitor VX-765 and the ROS scavenger NAC. T2DM rats demonstrated impaired glucose tolerance but stable hemodynamics during CPB, while showing heightened vulnerability to MI/R injury. This was marked by substantial lipid deposition, disrupted myocardial fibers, and intensified cellular apoptosis. The activation of caspase-1-mediated pyroptosis and increased reactive oxygen species (ROS) production further contributed to tissue damage and the ensuing inflammatory response. Notably, myocardial injury was mitigated by inhibiting caspase-1 through VX-765, which also attenuated the inflammatory cascade. Likewise, NAC treatment reduced oxidative stress and partially suppressed ROS-mediated caspase-1 activation, resulting in diminished myocardial injury. This study proved that Caspase-1-dependent pyroptosis significantly contributes to the inflammation and injury stemming from global MI/R in T2DM rats under CPB, which correlate with the surplus ROS generated by oxidative stress during reperfusion.

Objective To investigate the role of sodium-hyaluronate-modified calcium peroxide nanoparticles (SH-CaO2 NPs) in inducing pyroptosis in human gastric cancer cells and its possible mechanisms. Methods Transmission electron microscopy (TEM), X-ray diffraction (XRD), infrared spectroscopy, and zeta potential test were used to confirm the synthesis of SH-CaO2 NPs. Cell scratch assay and CCK-8 assay were employed to observe the impacts of SH-CaO2 NPs on the migration and proliferation of human gastric cancer cell line HGC-27. The generation of reactive oxygen species (ROS) was observed with confocal laser scanning microscopy (CLSM) and quantified with flow cytometry in the cells after SH-CaO2 NPs treatment or with pretreatment with ROS inhibitor NAC. Furthermore, the effects of pretreatment of NLRP3 inhibitor (MCC950) and Caspase-1 inhibitor (VX765) on the proliferative activity and on expression of their own and their downstream GSDMD in HGC-27 cells were also investigated with CCK-8 assay, immunofluorescence assay and Western blotting. Results TEM images, XRD, infrared spectroscopy, and zeta potential test confirmed the successful preparation of SH-CaO2 NPs. Cell scratch assay and CCK-8 assay showed that application of SH-CaO2 NPs for 24 h significantly inhibited the proliferation of HGC-27 cells (P < 0.001), while, CLSM and flow cytometry indicated the treatment also promoted the production of ROS (P < 0.001). Pretreatment of ROS inhibitor NAC resulted in up-regulation of NLRP3, and increased expression levels of cleaved Caspase-1 and N-terminal fragment of GSDMD (P < 0.001), while pretreatment of both NLRP3 inhibitor and Caspase-1 inhibitor could reverse the process. Conclusion SH-CaO2 NPs inhibit cell viability of human gastric cancer, which may mediate the inflammatory response and pyroptosis by activating the ROS/NLRP3/Caspase-1/GSDMD signaling pathway.

Abdullah Al Mamun,1,2 Chuxiao Shao,1 Peiwu Geng,1 Shuanghu Wang,1 Jian Xiao1– 3 1Central Laboratory of The Lishui Hospital of Wenzhou Medical University, Lishui People’s Hospital, Lishui, Zhejiang, 323000, People’s Republic of China; 2Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of China; 3Department of Wound Healing, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of ChinaCorrespondence: Jian Xiao, Central Laboratory of The Lishui Hospital of Wenzhou Medical University, Lishui People’s Hospital, Lishui, Zhejiang, 323000, People’s Republic of China, Email xfxj2000@126.com Shuanghu Wang, Central Laboratory of The Lishui Hospital of Wenzhou Medical University, Lishui People’s Hospital, Lishui, Zhejiang, 323000, People’s Republic of China, Email wangshuanghu@lsu.edu.cnAbstract: Pyroptosis is a pro-inflammatory form of cell death resulting from the activation of gasdermins (GSDMs) pore-forming proteins and the release of several pro-inflammatory factors. However, inflammasomes are the intracellular protein complexes that cleave gasdermin D (GSDMD), leading to the formation of robust cell membrane pores and the initiation of pyroptosis. Inflammasome activation and gasdermin-mediated membrane pore formation are the important intrinsic processes in the classical pyroptotic signaling pathway. Overactivation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome triggers pyroptosis and amplifies inflammation. Current evidence suggests that the overactivation of inflammasomes and pyroptosis may further induce the progression of cancers, nerve injury, inflammatory disorders and metabolic dysfunctions. Current evidence also indicates that pyroptosis-dependent cell death accelerates the progression of diabetes and its frequent consequences including diabetic peripheral neuropathy (DPN). Pyroptosis-mediated inflammatory reaction further exacerbates DPN-mediated CNS injury. Accumulating evidence shows that several molecular signaling mechanisms trigger pyroptosis in insulin-producing cells, further leading to the development of DPN. Numerous studies have suggested that certain natural compounds or drugs may possess promising pharmacological properties by modulating inflammasomes and pyroptosis, thereby offering potential preventive and practical therapeutic approaches for the treatment and management of DPN. This review elaborates on the underlying molecular mechanisms of pyroptosis and explores possible therapeutic strategies for regulating pyroptosis-regulated cell death in the pharmacological treatment of DPN. Keywords: Diabetes mellitus, Diabetic peripheral neuropathy, Inflammation, Pyroptosis, NLRP3, Caspase-1, GSDMD, IL-1β and IL-18

Wanjun Gu, Qi Zeng, Xin Wang, Huthaifa Jasem, Ling Ma Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, People’s Republic of ChinaCorrespondence: Ling Ma, No. 36 Sanhao Street, Heping District, Shenyang, 110004, People’s Republic of China, Tel +86-18940256927, Email mal@cmu.edu.cnAbstract: Acute lung injury (ALI) manifests through harm to the capillary endothelium and alveolar epithelial cells, arising from a multitude of factors, leading to scattered interstitial alterations, pulmonary edema, and subsequent acute hypoxic respiratory insufficiency. Acute lung injury (ALI), along with its more serious counterpart, acute respiratory distress syndrome (ARDS), carry a fatality rate that hovers around 30– 40%. Its principal pathological characteristic lies in the unchecked inflammatory reaction. Currently, the main strategies for treating ALI are alleviation of inflammation and prevention of respiratory failure. Concerning the etiology of ALI, NLRP3 Inflammasome is essential to the body’s innate immune response. The composition of this inflammasome complex includes NLRP3, the pyroptosis mediator ASC, and pro-caspase-1. Recent research has reported that the inflammatory response centered on NLRP3 inflammasomes plays a key part in inflammation in ALI, and may hence be a prospective candidate for therapeutic intervention. In the review, we present an overview of the ailment characteristics of acute lung injury along with the constitution and operation of the NLRP3 inflammasome within this framework. We also explore therapeutic strategies targeting the NLRP3 inflammasome to combat acute lung injury.Keywords: acute lung injury, NLRP3 inflammasome, caspase-1, IL-1β, IL-18

The innate immune system serves as the first line of defense against β-coronaviruses (β-CoVs), a family of viruses that includes SARS-CoV-2. Viral sensing via pattern recognition receptors triggers inflammation and cell death, which are essential components of the innate immune response that facilitate viral clearance. However, excessive activation of the innate immune system and inflammatory cell death can result in uncontrolled release of proinflammatory cytokines, resulting in cytokine storm and pathology. PANoptosis, innate immune, inflammatory cell death initiated by innate immune sensors and driven by caspases and RIPKs through PANoptosome complexes, has been implicated in the pathology of viral infections. Therefore, understanding the molecular mechanisms regulating PANoptosis in response to β-CoV infection is critical for identifying new therapeutic targets that can mitigate disease severity. In the current study, we analyzed findings from a cell death-based CRISPR screen with archetypal β-CoV mouse hepatitis virus (MHV) as the trigger to characterize host molecules required for inflammatory cell death. As a result, we identified SMARCA4, a chromatin regulator, as a putative host factor required for PANoptosis in response to MHV. Furthermore, we observed that gRNA-mediated deletion of Smarca4 inhibited MHV-induced PANoptotic cell death in macrophages. These findings have potential translational and clinical implications for the advancement of treatment strategies for β-CoVs and other infections. [ABSTRACT FROM AUTHOR]

Background: Diabetes mellitus commonly causes endothelial cell and smooth muscle cell death in penile cavernous tissue. Aim: The study sought to study the mode of cell death in the penile cavernous tissue in type 1 diabetic rats. Methods: A total of 36 Sprague Dawley rats 10 weeks of age were randomly divided into 2 groups: a normoglycemic group and type 1 diabetic group (intraperitoneal injection of Streptozotocin (STZ), 60 mg/kg). We randomly selected 6 rats from each group for tests at the end of 11, 14, and 18 weeks of age, respectively. All rats were able to eat and drink freely. The ratio of maximum intracavernous pressure to mean arterial pressure, concentration of serum testosterone, level of nitric oxide in the penile cavernosum, and expression of active caspase-1 (pyroptosis) and active caspase-3 (apoptosis) were determined. Outcomes: At the end of weeks 4 and 8 of type 1 diabetes, the proportions of endothelial cells and smooth muscle cells undergoing apoptosis and pyroptosis in penile cavernous tissue are different. Results: The ratio of maximum intracavernous pressure to mean arterial pressure and nitric oxide levels were significantly lower in the 4- and 8-week diabetic groups than in the normoglycemic group (P <.01). Penile endothelial cell pyroptosis (5.67 ± 0.81%), smooth muscle cell apoptosis (23.72 ± 0.48%), total cell pyroptosis (9.67 ± 0.73%), and total apoptosis (10.52 ± 1.45%) were significantly greater in the 4-week diabetic group than in the normoglycemic group (P <.01). The proportion of endothelial cell pyroptosis (24.4 ± 3.69%), endothelial cell apoptosis (22.13 ± 2.43%), total cell pyroptosis (14.75 ± 0.93%), and total apoptosis (14.82 ± 1.08%) in the penile tissues of the 8-week diabetic group were significantly greater than those in the normoglycemic group (P <.01).The 8-week survival proportions of diabetic endothelial cells (38.86 ± 8.85%) and smooth muscle cells (44.46 ± 2.94%) was significantly lower than the 4-week survival proportions of endothelial cells (93.17 ± 8.07%) and smooth muscle cells (75.12 ± 4.76%) (P <.05). Clinical Translation: Inhibition of cell death by different methods at different stages may be the key to the treatment of type 1 diabetes–induced erectile dysfunction. Strengths and Limitations: The effect of type 1 diabetes on other types of cell death in penile cavernous tissue needs further study. Conclusion: The mode of death of endothelial cells in the cavernous tissue of the penis in the early stage in diabetic rats is dominated by pyroptosis, and the death of smooth muscle cells is dominated by apoptosis. Endothelial cell and smooth muscle cell death are not consistent at different stages of diabetes progression. [ABSTRACT FROM AUTHOR]

Myocarditis is an inflammatory disease of the cardiac muscle and one of the primary causes of dilated cardiomyopathy. Group B coxsackievirus (CVB) is one of the leading causative pathogens of viral myocarditis, which primarily affects children and young adults. Due to the lack of vaccines, the development of antiviral medicines is crucial to controlling CVB infection and the progression of myocarditis. In this study, we investigated the antiviral effect of baicalein, a flavonoid extracted from Scutellaria baicaleinsis. Our results demonstrated that baicalein treatment significantly reduced cytopathic effect and increased cell viability in CVB3-infected cells. In addition, significant reductions in viral protein 3D, viral RNA, and viral particles were observed in CVB3-infected cells treated with baicalein. We found that baicalein exerted its inhibitory effect in the early stages of CVB3 infection. Baicalein also suppressed viral replication in the myocardium and effectively alleviated myocarditis induced by CVB3 infection. Our study revealed that baicalein exerts its antiviral effect by inhibiting the activity of caspase-1 and viral protease 2A. Taken together, our findings demonstrate that baicalein has antiviral activity against CVB3 infection and may serve as a potential therapeutic option for the myocarditis caused by enterovirus infection. [ABSTRACT FROM AUTHOR]

Object: This study aims to investigate the molecular mechanism of NDRG2 (N-myc downstream-regulated gene 2) in the cell senescence of lens endothelial cells. Methods: Lens endothelial cells (SRA01/04) were irradiated with UVB at different times. Cell viability was measured by CCK-8 kit and cell cycle was detected by flow cytometry. Cell senescence was detected using SA-β-gal staining. Western blot was utilized to detect the expressions of p53, p21 and NDRG2. TUNEL staining and flow cytometry were used to detect apoptosis and pyroptosis. Results: UVB-irradiation significantly induces cell senescence and the expression of NDRG2, p53 and p21 in SRA01/04 cells was up-regulated. Down-regulation of NDRG2 inhibited UVB-induced cell senescence, significantly reversed pyroptosis and promoted cell proliferation. UVB-induced pyroptosis is closely related to caspase-1/NLRP3 axis. Conclusion: Our study confirmed downregulation of NDRG2 significantly inhibited UVB radiation-induced cell senescence by regulating caspase-1/NLRP3-mediated pyroptosis. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the role of absent in melanoma 2 (AIM2) inflammasome-mediated pyroptosis in the pathogenesis of acute gouty arthritis (AGA) and asymptomatic hyperuricemia(AHU). Methods: A cohort of 30 AGA patients, 30 AHU individuals, and 30 healthy controls (HC) was assembled. Demographic and biochemical data, along with blood samples, were collected. Serum double-stranded DNA (dsDNA) levels were quantified using a fluorescent assay. Transcriptomic and proteomic analysis of AIM2, Caspase-1, GSDMD, IL-1b, and IL-18 in peripheral blood mononuclear cells was performed using qRT-PCR and Western blot. Enzyme-linked immunosorbent assay (ELISA) was employed to measure serum IL-1b and IL-18. Spearman correlation analysis was utilized to assess relationships between variables. Results: Both AGA and AHU groups demonstrated elevated metabolic indicators and serum levels of dsDNA, IL-1b, and IL-18 compared to the HC group. AGA patients exhibited higher inflammatory markers than the AHU group. In the AGA group, there was a significant increase in the mRNA and protein levels of AIM2, Caspase-1, GSDMD, IL-1b, and IL-18 (P<0.05 to P<0.001). The AHU group showed higher AIM2, Caspase-1, GSDMD, and IL-18 mRNA levels than the HC group (P<0.001 to P<0.01), with a non-significant increase in AIM2, GSDMD, and IL-1b proteins (P>0.05). In contrast, Caspase-1 and IL-18 proteins were significantly higher in the AHU group (P<0.05). Notable correlations were observed between AIM2 protein expression and levels of Caspase-1 and GSDMD in both AGA and AHU groups. In the AGA group, AIM2 protein correlated with IL-1b, but not in the AHU group. The AIM2 protein in the AHU group was positively associated with IL-18, with no such correlation in the AGA group. Conclusion: AIM2 inflammasome may play a role in the inflammatory processes of AGA and AHU and that its activation may be related to the pyroptosis pathway. [ABSTRACT FROM AUTHOR]

Interstitial cystitis (IC) is a chronic bladder inflammation. Inhibition of prostaglandin G/H synthase 2 (PTGS2) is the most common method for controlling inflammation-related diseases. This study aimed to analyze the effects of hispidulin on the PTGS2 and NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammation in experimental IC models. A binding activity between hispidulin and PTGS2 was measured using molecular docking. Human urothelial cells (SV-HUC-1) were stimulated by 2 ng/mL of interleukin (IL)-1β for 24 h and cultured in a medium with different concentrations of hispidulin (2.5, 5, 10, 20 µM) for 24 h to observe the expressions of PTGS2 and NLRP3 protein. Cells overexpressing PTGS2 were established by PTGS2 cDNA transfection. In the IL-1β-treated cells, the NLRP3 inflammasome was measured after 20 µM hispidulin treatment. In rats, animals were performed with three injections of 40 mg/kg cyclophosphamide (CYP) and orally treated with 50 mg/kg/day hispidulin or ibuprofen for 3 days. The bladder pain was measured using Von Frey filaments, and the bladder pathology was observed using hematoxylin and eosin (H&E) staining. The expressions of PTGS2 and NLRP3 inflammasome were also observed in the bladder tissues. A good binding activity was found between hispidulin and PTGS2 (score = − 8.9 kcal/mol). The levels of PTGS2 and NLRP3 inflammasome were decreased with the hispidulin dose increase in the IL-1β-treated cells (p < 0.05). Cells overexpressing PTGS2 weakened the protective effects of hispidulin in the IL-1β-treated cells (p < 0.01). In the CYP-treated rats, hispidulin treatment improved the bladder pain through decreasing the nociceptive score (p < 0.01) and suppressed the bladder inflammation through suppressing the expressions of PTGS2 and NLRP3 inflammasome in bladder tissues (p < 0.01). Additionally, the results of ibuprofen treatment were similar to the effects of hispidulin in the CYP-treated rats. This study demonstrates that hispidulin may be a new alternative drug for the IC treatment that binds PTGS2 to perform its functions. [ABSTRACT FROM AUTHOR]

Inflammation through activation of caspase‐1, seems to play a role in pulmonary hypertension induced by alveolar hypoxia. Whether alveolar hypoxia induces caspase‐1‐mediated inflammation and influx of leukocytes in other organs than the lungs, is not known. Our aim was to explore sites of caspase‐1‐related inflammation in alveolar hypoxia. Wild type (WT) mice were exposed to environmental hypoxia or room‐air, and organs were analyzed. Right heart catheterization was performed after 14 days of alveolar hypoxia in WT mice and mice transplanted with WT or caspase‐1−/− bone marrow. Hypoxia induced leukocyte accumulation and increased caspase‐1 protein in the lungs, not in other organs. WT mice transplanted with WT or caspase‐1−/− bone marrow showed no difference in pulmonary leukocyte accumulation or development of pulmonary hypertension after alveolar hypoxia. Caspase‐1 and IL‐18 were detected in bronchial epithelium in WT mice, and hypoxia induced IL‐18 secretion from bronchial epithelial cells. IL‐18 stimulation generated IL‐6 mRNA in monocytes. Phosphorylated STAT3 was increased in hypoxic lungs, not in other organs. Alveolar hypoxia induces caspase‐1 activation and leukocyte accumulation specific to the lungs, not in other organs. Caspase‐1 activation and IL‐18 secretion from bronchial epithelial cells might initiate hypoxia‐induced inflammation, leading to pulmonary hypertension. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy (CH) is an adaptive response to maintain cardiac function; however, persistent stress responses lead to contractile dysfunction and heart failure. Although inflammation is involved in these processes, the mechanisms that control cardiac inflammation and hypertrophy still need to be clarified. The NLRP3 inflammasome is a cytosolic multiprotein complex that mediates IL-1β production. The priming step of NLRP3 is essential for increasing the expression of its components and occurs following NF-κB activation. Hyperthyroidism triggers CH, which can progress to maladaptive CH and even heart failure. We have shown in a previous study that thyroid hormone (TH)-induced CH is linked to the upregulation of S100A8, leading to NF-κB activation. Therefore, we aimed to investigate whether the NLRP3 inflammasome is involved in TH-induced CH and its potential role in CH pathophysiology. Hyperthyroidism was induced in NLRP3 knockout (NLRP3-KO), Caspase-1-KO and Wild Type (WT) male mice of the C57Bl/6J strain, aged 8–12 weeks, by triiodothyronine (7 μg/100 g BW, i.p.) administered daily for 14 days. Morphological and cardiac functional analysis besides molecular assays showed, for the first time, that TH-induced CH is accompanied by reduced NLRP3 expression in the heart and that it occurs independently of the NLRP3 inflammasome and caspase 1-related pathways. However, NLRP3 is important for the maintenance of basal cardiac function since NLRP3-KO mice had impaired diastolic function and reduced heart rate, ejection fraction, and fractional shortening compared with WT mice. [ABSTRACT FROM AUTHOR]

Objective: The pleiotropic effect of hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) is responsible for potent defense against inflammatory response. This study evaluated the inhibitory effects of HMG-CoA reductase inhibitors on the monosodium urate (MSU)-induced inflammatory response through the regulation of interleukin-37 (IL-37) expression. Methods: Serum was collected from patients with gout (n = 40) and from healthy controls (n = 30). The mRNA and protein expression of the target molecules IL-1β, IL-37, caspase-1, and Smad3 were measured in THP-1 macrophages stimulated with MSU, atorvastatin, or rosuvastatin using a real-time quantitative polymerase chain reaction and Western blot assay. Transfection with IL-1β or Smad3 siRNA in THP-1 macrophages was used to verify the pharmaceutical effect of statins in uric-acid-induced inflammation. Results: Serum IL-37 levels in gout patients were significantly higher than in controls (p < 0.001) and was associated with the serum uric acid level (r = 0.382, p = 0.008). THP-1 cells stimulated with MSU markedly induced IL-37 mRNA expression and the transition of IL-37 from the cytoplasm to the nucleus. Recombinant IL-37 treatment dose-dependently inhibited activation of caspase-1 and IL-1β in MSU-induced inflammation. Atorvastatin and rosuvastatin attenuated caspase-1 activation and mature IL-1β expression but augmented translocation of IL-37 from the cytoplasm to the nucleus. Atorvastatin and rosuvastatin induced phosphorylation of Smad3 in THP-1 cells treated with MSU crystals. Statins potently attenuated translocation of IL-37 from the cytoplasm to the nucleus in THP-1 macrophages transfected with Smad3 siRNA compared to cells with negative control siRNA. Conclusions: This study revealed that statins inhibit the MSU-induced inflammatory response through phosphorylated Smad3-mediated IL-37 expression in THP-1 macrophages. [ABSTRACT FROM AUTHOR]

Background: Mounting evidence links glucose intolerance and diabetes as aspects of metabolic dysregulation that are associated with an increased risk of developing dementia. Inflammation and inflammasome activation have emerged as a potential link between these disparate pathologies. As diet is a key factor in both the development of metabolic disorders and inflammation, we hypothesize that long term changes in dietary factors can influence nervous system function by regulating inflammasome activity and that this phenotype would be sex-dependent, as sex hormones are known to regulate metabolism and immune processes. Methods: 5-week-old male and female transgenic mice expressing a caspase-1 bioluminescent reporter underwent cranial window surgeries and were fed control (65% complex carbohydrates, 15% fat), high glycemic index (65% carbohydrates from sucrose, 15% fat), or ketogenic (1% complex carbohydrates, 79% fat) diet from 6 to 26 weeks of age. Glucose regulation was assessed with a glucose tolerance test following a 4-h morning fast. Bioluminescence in the brain was quantified using IVIS in vivo imaging. Blood cytokine levels were measured using cytokine bead array. 16S ribosomal RNA gene amplicon sequencing of mouse feces was performed to assess alterations in the gut microbiome. Behavior associated with these dietary changes was also evaluated. Results: The ketogenic diet caused weight gain and glucose intolerance in both male and female mice. In male mice, the high glycemic diet led to increased caspase-1 biosensor activation over the course of the study, while in females the ketogenic diet drove an increase in biosensor activation compared to their respective controls. These changes correlated with an increase in inflammatory cytokines present in the serum of test mice and the emergence of anxiety-like behavior. The microbiome composition differed significantly between diets; however no significant link between diet, glucose tolerance, or caspase-1 signal was established. Conclusions: Our findings suggest that diet composition, specifically the source and quantity of carbohydrates, has sex-specific effects on inflammasome activation in the central nervous system and behavior. This phenotype manifested as increased anxiety in male mice, and future studies are needed to determine if this phenotype is linked to alterations in microbiome composition. [ABSTRACT FROM AUTHOR]

The interleukin (IL)‐1 family of cytokines plays a pivotal role in immune responses. Among the members of IL‐1 family, IL‐1β is synthesized as an inactive precursor (pro‐IL‐1β) and becomes active upon cleavage, which is typically facilitated by inflammasomes through caspase‐1. In our research, we explored the potential role of caspase‐3 in the cleavage of pro‐IL‐1β and found that caspase‐3 cleaves pro‐IL‐1β, specifically at Asp26. Moreover, we found that in the absence of caspase‐3 cleavage, the release of active IL‐1β via the inflammasome is increased. Our study introduces pro‐IL‐1β as a new substrate for caspase‐3 and suggests that caspase‐3‐mediated cleavage has the potential to suppress IL‐1β‐mediated inflammatory responses. [ABSTRACT FROM AUTHOR]

Epilepsy is one of the most prevalent and serious brain disorders and affects over 70 million people globally. Antiseizure medications (ASMs) relieve symptoms and prevent the occurrence of future seizures in epileptic patients but have a limited effect on epileptogenesis. Addressing the multifaceted nature of epileptogenesis and its association with the Nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated neuroinflammation requires a comprehensive understanding of the underlying mechanisms of these medications for the development of targeted therapeutic strategies beyond conventional antiseizure treatments. Several types of NLRP3 inhibitors have been developed and their effect has been validated both in in vitro and in vivo models of epileptogenesis. In this review, we discuss the advances in understanding the regulatory mechanisms of NLRP3 activation as well as progress made, and challenges faced in the development of NLRP3 inhibitors for the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

Allergic inflammation is the foundation of multiple allergic disorders, such as allergic rhinitis and asthma. Mast cells are effector cells that initiate inflammatory response. 5-hydroxymethylfurfural (5-HMF), a furfural compound, is the heat-processed product of various fruit, foods, drinks, as well as some Chinese herbal medicines. 5-HMF was previously reported to inhibit mast cell activation. Our study aimed to explore the functions of 5-HMF in both phorbol 12-mystate 13-acetate (PMA) plus calcium ionophore (A23187)-induced allergic inflammation in human mast cell line HMC-1 and ovalbumin (OVA)-induced asthma mouse models. HMC-1 cells were pretreated with 5-HMF and then stimulated by PMA+A23187. The cytotoxicity of 5-HMF on HMC-1 cells was evaluated by MTT assay. Histamine content in cell supernatants was measured by the o-phthaldialdehyde spectrofluorometric procedure. Intracellular calcium was determined using the fluorescent dye Fura-2AM. The production and expression of pro-inflammatory cytokines were detected by ELISA and RT-qPCR. Caspase-1 colorimetric assay was employed to examine the enzymatic activity of caspase-1. Asthma mouse models were induced by OVA sensitization. The bronchoalveolar lavage fluid (BALF) and blood samples were collected for the detection of total and differential cell count as well as aspartate aminotransferase (AST), alanine aminotransferase (ALT), OVA-immunoglobulin E (OVA-IgE), OVA-immunoglobulin G1 (OVA-IgG1), and pro-inflammatory cytokine levels. The left lung of mouse was dissected for histopathological examination by hematoxylin and eosin (H&E) staining. The protein expression of pro-caspase-1 and the phosphorylation of NF-κB and MAPK pathway-associated molecules were assessed by Western blotting. Our findings revealed that 5-HMF efficiently suppressed the PMA+A23187-induced enhancement in histamine production and intracellular calcium in HMC-1 cells. Pro-inflammatory cytokine production and expression in HMC-1 cells were elevated after PMA plus A23187 stimulation, which, however, were inhibited by pretreatment of 5-HMF. Additionally, 5-HMF suppressed the activity of caspase-1 and the phosphorylation of NF-κB and MAPK-associated molecules including p65 NF-κB, p38 MAPK, ERK, and JNK in HMC-1 cells. In vivo experiments demonstrated that 5-HMF treatment reduced the lung/body weight index and total and differential (macrophages, neutrophils, lymphocytes, and eosinophils) cell counts in BALF of asthmatic mice, but exerted no influence on serum AST and ALT levels. Besides, 5-HMF reduced serum OVA-IgE and OVA-IgG1 levels, mitigated lung inflammation, and inhibited the NF-κB and MAPK signaling pathways in asthma mouse models. 5-HMF mitigates allergic inflammation in asthma by inactivating caspase-1 and NF-κB and MAPK signaling pathways. [ABSTRACT FROM AUTHOR]

Background: Astragaloside IV (AS‐IV) is the most active monomer in the traditional Chinese herbal medicine Radix Astragali, which has a wide range of antiviral, anti‐inflammatory, and antifibrosis pharmacological effects, and shows protective effects in acute lung injury. Methods: This study utilized the immunofluorescence, flow cytometry, enzyme‐linked immunosorbent assay, quantitative reverse transcription‐polymerase chain reaction, western blot, and hematoxylin and eosin staining methods to investigate the mechanism of AS‐IV in reducing viral pneumonia caused by influenza A virus in A549 cells and BALB/c mice. Results: The results showed that AS‐IV suppressed reactive oxygen species production in influenza virus‐infected A549 cells in a dose‐dependent manner, and subsequently inhibited the activation of nucleotide‐binding oligomerization domain‐like receptor thermal protein domain associated protein 3 inflammasome and Caspase‐1, decreased interleukin (IL) ‐1β and IL‐18 secretion. In BALB/c mice infected with Poly (I:C), oral administration of AS‐IV can significantly reduce Poly (I:C)‐induced acute pneumonia and lung pathological injury. Conclusions: AS‐IV alleviates the inflammatory response induced by influenza virus in vitro and lung flammation and structural damage caused by poly (I:C) in vivo. [ABSTRACT FROM AUTHOR]

Sepsis-induced disseminated intravascular coagulation (DIC) is characterised by abnormal blood clotting resulting from severe infection, contributing to organ dysfunction in sepsis. Resolvin D1 (RvD1) is an endogenous lipid mediator, synthesised from the omega-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) through enzymatic processes involving 15-LOX and 5-LOX. RvD1 is recognised for its protective properties against various inflammatory conditions. This study aims to investigate its potential to modulate coagulation dysfunction in sepsis and to evaluate coagulation disorders in septic patients. Sepsis models were established by intraperitoneal injection LPS (20 mg/kg) or cecal ligation and puncture (CLP) followed by injection of RvD1 (10 μg/kg) or saline. The impact of RvD1 on coagulation dysfunction was assessed by clotting time and coagulation indicators such as TAT, D-dimer, PAI-1, and fibrinogen. The activity of the coagulation system in vivo was observed by evaluating dynamic microcirculation, platelets and thrombin in mice using intravital microscopy. The effect of RvD1 on pyroptosis was investigated by measuring NOD-like receptor protein 3 (NLRP3), Caspase-1, Caspase-11, and Gasdermin D (GSDMD) levels via western blot. Caspase-1 knockout mice, GSDMD knockout mice and bone marrow-derived macrophages (BMDMs) were used to elucidate the underlying mechanisms. Lastly, the concentration of RvD1 in plasma from septic patients was quantified to explore its relationship with coagulation and pyroptosis. RvD1 significantly attenuated coagulation dysfunction in septic mice induced by LPS and CLP, and inhibited Caspase-1/GSDMD-dependent pyroptosis in septic mice and bone marrow-derived macrophages. In septic patients, the plasma concentrations of RvD1 was negatively correlated with both coagulation-related indicators and markers of GSDMD activation. The results suggest that RvD1 can improve coagulation dysfunction in sepsis by regulating the Caspase-1/GSDMD pyroptotic pathway. Additionally, the concentration of RvD1 in septic patient plasma is related to prognosis and DIC development. RvD1 could be a potential biomarker and a promising therapeutic alternative in sepsis-induced DIC. [Display omitted] [ABSTRACT FROM AUTHOR]

Pyroptosis is a pro-inflammatory form of cell death resulting from the activation of gasdermins (GSDMs) pore-forming proteins and the release of several pro-inflammatory factors. However, inflammasomes are the intracellular protein complexes that cleave gasdermin D (GSDMD), leading to the formation of robust cell membrane pores and the initiation of pyroptosis. Inflammasome activation and gasdermin-mediated membrane pore formation are the important intrinsic processes in the classical pyroptotic signaling pathway. Overactivation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome triggers pyroptosis and amplifies inflammation. Current evidence suggests that the overactivation of inflammasomes and pyroptosis may further induce the progression of cancers, nerve injury, inflammatory disorders and metabolic dysfunctions. Current evidence also indicates that pyroptosis-dependent cell death accelerates the progression of diabetes and its frequent consequences including diabetic peripheral neuropathy (DPN). Pyroptosis-mediated inflammatory reaction further exacerbates DPN-mediated CNS injury. Accumulating evidence shows that several molecular signaling mechanisms trigger pyroptosis in insulin-producing cells, further leading to the development of DPN. Numerous studies have suggested that certain natural compounds or drugs may possess promising pharmacological properties by modulating inflammasomes and pyroptosis, thereby offering potential preventive and practical therapeutic approaches for the treatment and management of DPN. This review elaborates on the underlying molecular mechanisms of pyroptosis and explores possible therapeutic strategies for regulating pyroptosis-regulated cell death in the pharmacological treatment of DPN. [ABSTRACT FROM AUTHOR]

Bronchopulmonary dysplasia (BPD) is a common serious complication of premature babies. No effective means control it. Hyperoxia damage is one of the important mechanisms of BPD. The reaserach confirmed pyroptosis existed in BPD. Dexmedetomidine is a new, high-specific a2 receptor agonist. Previous research foundation found that dexmedetomidine has a protective effect on BPD. To investigate how dexmedetomidine improves hyperoxic lung injury in neonatal mice by regulating pyroptosis. Neonatal rats were randomly divided into four groups: normal control group, hyperoxic injury group, air plus dexmedetomidine group, and hyperoxia plus dexmedetomidine group. After seven days the lungs of rats in each group were extracted, and the wet-to-dry weight ratio of the lung was measured. The lung injury in rats was observed using hematoxylin-eosin staining. Additionally, the expression and localization of nucleotidebinding oligomerization domain-like receptor thermal protein domain associated protein 3 (NLRP3), apoptosisassociated speck-like protein (ASC), and gasdermin D (GSDMD) proteins were examined in the lungs of rats using immunofluorescence staining. The mRNA levels of NLRP3, ASC, caspase-1, and interleukin 18 (IL-18) in the lungs of rats were determined using real-time PCR. Moreover, the protein levels of NLRP3, ASC, caspase-1/cleaved caspase-1, interleukin 1beta (IL-1b), IL-18, and tunor necrosis factor alpha (TNF-a) were detected in lungs of rats using Western blot. The extent of mitochondrial damage in lung tissues of each group was observed by transmission electron microscopy. The lung tissue injury of the neonatal rats was significantly improved in the hyperoxia plus dexmedetomidine group compared to the hyperoxic injury group. Furthermore, the expressions of pyroptosis-related proteins such as NLRP3, ASC, cleaved-caspase-1, and GSDMD were significantly decreased, along with the expressions of inflammatory factors in lung tissues. By inhibiting the NLRP3/caspase-1/GSDMD pyroptosis pathway, dexmedetomidine reduces the activation and release of inflammatory factors and provides a protective effect against hyperoxic lung injury in neonatal mice. [ABSTRACT FROM AUTHOR]

IntroductionInflammation and cell death play an important role in the pathogenesis of diabetic retinopathy. Previously we observed sustained activation of pro-inflammatory caspase-1 in retinas of diabetic animals and patients. In this study, we aimed to look at mechanisms underlying chronic caspase-1 activation in vitro and in vivo.MethodsNon-diabetic and diabetic wild type and IL-1 receptor (IL-1R1) knockout mice were used for in vivo experiments. Diabetes was induced using STZ (streptozotocin). Human Müller cells were used for in vitro studies. Cells were treated with either 5 mM or 25 mM glucose or interleukin-1beta (IL-1β) in the presence or absence of IL-1 receptor antagonist (IL-1ra) or siRNA against RIP2 (receptor interacting protein-2) for up to 96 h. Outcome measurements to assess Müller cell functions included measurements of caspase-1 activity using a fluorescence peptide substrate, production of IL-1β by Elisa, and cell death using trypan blue exclusion assays.ResultsOur in vivo results demonstrate that caspase-1 activation progresses from an IL-1R1 independent mechanism at 10 weeks of diabetes to an IL-1R1 dependent mechanism at 20 weeks indicating that feedback through IL-1R1 is crucial for sustained caspase-1 activity in retinas of mice. A similar hyperglycemia-mediated caspase-1/IL-1β/IL-1R1 feedback signaling was detected in vitro in human Müller cells which was prevented by treatment with IL-1ra. Our data also indicate that hyperglycemia induces caspase-1 activation initially but IL-1β sustains caspase-1 activation via caspase-1/IL-1β/IL-1R1 feedback and we identified RIP2 as mediator for both hyperglycemia- and IL-1β-induced caspase-1 activation. Activation of caspase-1/IL-1β/IL-1R1 feedback signaling caused Müller cell death which was prevented by RIP2 knockdown.DiscussionWe conclude that any intervention in caspase-1/IL-1β/IL-1R1 feedback signaling presents novel therapeutic options for the treatment of diabetic retinopathy.

Purpose: Periodontitis is associated with caspase and proinflammatory mediators, such as caspase-1 and tumor necrosis factor-alpha (TNF-α). The aim of this study was to evaluate the salivary levels of caspase-1 and TNF-α and determine their accuracy in differentiating periodontitis patients from individuals with a healthy periodontium. Materials and Methods: This case-control study enrolled 90 subjects, aged 30 to 55, attending the Department of Periodontics at Baghdad's outpatient clinic. Patients were initially screened to evaluate their eligibility for recruitment. After applying inclusion/exclusion criteria, subjects with a healthy periodontium were included in group 1 (controls), while subjects with periodontitis were included in group 2 (patients). The salivary levels of caspase-1 and TNF-α in participants' unstimulated saliva were measured using an enzyme-linked immunosorbent assay (ELISA). Then the periodontal status was determined using the following indices: full-mouth plaque, full-mouth bleeding on probing, probing pocket depth, clinical attachment level, and gingival recession. Results: TNF-α and caspase-1 salivary levels were higher in periodontitis patients than in healthy controls and were positively correlated with all clinical parameters. A positive significant correlation between TNF-α and caspase-1 salivary levels was noticed. For differentiating periodontal health and periodontitis, the area under the curve (AUC) values of TNF-α and caspase-1 were 0.978 and 0.998, while the proposed cut-off points were 128.163 pg/ml and 1.626 ng/ml, respectively. Conclusion: The present findings supported a previous discovery that periodontitis patients have significantly higher levels of salivary TNF-α. In addition, there was a positive correlation between the salivary levels of TNF-α and caspase-1. Furthermore, caspase-1 and TNF-α showed high sensitivity and specificity in the diagnosis of periodontitis, as well as distinguishing periodontitis from periodontal health. [ABSTRACT FROM AUTHOR]

Objective To compare the effectiveness between qPCR and trace-level proteins quantitative analysis in detecting the expression of inflammation-associated factors caspase-1 and IL-1β in peripheral blood monocytes from breast cancer patients. Methods Pre- and post-operation peripheral blood samples were collected from 10 breast cancer patients. Monocytes were subsequently isolated and activated by incubation with lipopolysaccharide. The mRNA and protein expression level of caspase-1 and IL-1β in monocytes were examined using qPCR and trace-level proteins quantitative analysis, respectively, and the data were normalized by β-actin. The differences between the two detection methods were compared and evaluated for strengthens and weakness. Results The vast majority of patients showed a notable increase in the number of peripheral blood monocytes after surgical operation. At the mRNA level, compared to preoperative levels, postoperative caspase-1 and IL-1β were both increased in 50% (5/10) and 40% (4/10) of patients, respectively, while the rest showed either a decrease (40% and 50%, respectively) or no significant change (both 10%). In contrast, the results of trace-level proteins quantitative analysis revealed that 60% (6/10) of patients exhibited increased level of postoperative caspase-1 and IL-1β proteins, while the remaining showed a decrease (30% and 20%, respectively) or no significant change (10% and 20%, respectively). Additionally, 50% of patients displayed a significant increase in caspase-1 and IL-1β active cleavage bands by electrophoresis postoperatively. Notably, inconsistent changes in caspase-1 and IL-1β mRNA and protein level after surgery were observed in 30% and 40% of patients respectively. Conclusions The trace-level proteins quantitative analysis is recommended due to its advantages including minimal sample amount requirement, high sensitivity, good repeatability and relatively simple operative procedure. Therefore, it is particularly suitable for assessing the inflammatory status of of patients through clinical sampling of peripheral blood.

Mengyang Li,1,&ast; Yuting Wang,2,&ast; He Liu,2 Xiaonan Huang,2 Huagang Peng,2 Yi Yang,2 Zhen Hu,2 Jianxiong Dou,2 Chuan Xiao,2 Juan Chen,3 Weilong Shang,2 Xiancai Rao1,2 1Department of Microbiology, School of Medicine, Chongqing University, Chongqing, 400044, People’s Republic of China; 2Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering Under the Educational Committee in Chongqing, Chongqing, 400038, People’s Republic of China; 3Department of Pharmacy, The Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Xiancai Rao; Weilong Shang, Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, 400038, People’s Republic of China, Email raoxiancai@126.com; shangwl0414@163.comIntroduction: Nanosized outer membrane vesicles (OMVs) from Gram-negative bacteria have attracted increasing interest because of their antitumor activity. However, the antitumor effects of MVs isolated from Gram-positive bacteria have rarely been investigated.Methods: MVs of Staphylococcus aureus USA300 were prepared and their antitumor efficacy was evaluated using tumor-bearing mouse models. A gene knock-in assay was performed to generate luciferase Antares2–MVs for bioluminescent detection. Cell counting kit-8 and lactic dehydrogenase release assays were used to detect the toxicity of the MVs against tumor cells in vitro. Active caspase-1 and gasdermin D (GSDMD) levels were determined using Western blot, and the tumor inhibition ability of MVs was determined in B16F10 cells treated with a caspase-1 inhibitor.Results: The vesicular particles of S. aureus USA300 MVs were 55.23 ± 8.17 nm in diameter, and 5 μg of MVs remarkably inhibited the growth of B16F10 melanoma in C57BL/6 mice and CT26 colon adenocarcinoma in BALB/c mice. The bioluminescent signals correlated well with the concentrations of the engineered Antares2–MVs (R2 = 0.999), and the sensitivity for bioluminescence imaging was 4 × 10− 3 μg. Antares2–MVs can directly target tumor tissues in vivo, and 20 μg/mL Antares2–MVs considerably reduced the growth of B16F10 and CT26 tumor cells, but not non-carcinomatous bEnd.3 cells. MV treatment substantially increased the level of active caspase-1, which processes GSDMD to trigger pyroptosis in tumor cells. Blocking caspase-1 activation with VX-765 significantly protected tumor cells from MV killing in vitro and in vivo.Conclusion: S. aureus MVs can kill tumor cells by activating the pyroptosis pathway, and the induction of pyroptosis in tumor cells is a promising strategy for cancer treatment. Keywords: Staphylococcus aureus, membrane vesicles, Antares2, cancer therapy, pyroptosis, caspase-1, GSDMD

Abstract Background Cardiac fibroblasts (CFs) are activated after initial injury, and then differentiate into myofibroblasts (MFs), which play a pivotal role as the primary mediator cells in pathological remodeling. Sodium butyrate (NaB), being a metabolite of gut microbiota, exhibits anti-inflammatory property in local therapies on sites other than the intestine. Thus, this study aimed to probe the mechanism by which NaB regulates CFs transdifferentiation through the NLRP3/Caspase-1 pyroptosis pathway. Methods CFs were cultured in vitro and induced into MFs by TGFβ1. CFs were identified by immunofluorescence labelling technique of vimentin and α-SMA, followed by treatment with NaB or NLRP3 inflammasome inhibitor (CY-09) and its activator [nigericin sodium salt (NSS)]. The expression levels of α-SMA, GSDMD-N/NLRP3/cleaved Caspase-1 proteins, and inflammatory factors IL-1β/IL-18/IL-6/IL-10 were determined using immunofluorescence, Western blot and ELISA. Cell proliferation and migration were evaluated using the CCK-8 assay and the cell scratch test, respectively. Results Following the induction of TGFβ1, CFs exhibited increased expression levels of α-SMA proteins and IL-6/IL-10, as well as cell proliferative and migratory abilities. TGFβ1 induced CFs to differentiate into MFs, while NaB inhibited this differentiation. NaB inactivated the NLRP3/Caspase-1 pyroptosis pathway. CY-09 demonstrated inhibitory effects on the NLRP3/Caspase-1 pyroptosis pathway, leading to a reduction in TGFβ1-induced CFs transdifferentiation. NSS activated the NLRP3/Caspase-1 pyroptosis pathway, and thus partially counteracting the inhibitory effect of intestinal microbiota metabolite NaB on CFs transdifferentiation. Conclusion NaB, a metabolite of the gut microbiota, inhibited the activation of the NLRP3/Caspase-1 pyroptosis pathway in TGFβ1-induced CFs, repressed the transdifferentiation of CFs into MFs.

Abdullah Al Mamun,1,2 Chuxiao Shao,1 Peiwu Geng,1 Shuanghu Wang,1 Jian Xiao2,3 1Central Laboratory of the Sixth Affiliated Hospital of Wenzhou Medical University, Lishui People’s Hospital, Lishui City, Zhejiang, 323000, People’s Republic of China; 2Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325000, People’s Republic of China; 3Department of Wound Healing, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, People’s Republic of ChinaCorrespondence: Jian Xiao, Email xfxj2000@126.comAbstract: Pyroptosis defines a form of pro-inflammatory-dependent programmed cell death triggered by gasdermin proteins, which creates cytoplasmic pores and promotes the activation and accumulation of immune cells by releasing several pro-inflammatory mediators and immunogenic substances upon cell rupture. Pyroptosis comprises canonical (mediated by Caspase-1) and non-canonical (mediated by Caspase-4/5/11) molecular signaling pathways. Numerous studies have explored the contributory roles of inflammasome and pyroptosis in the progression of multiple pathological conditions such as tumors, nerve injury, inflammatory diseases and metabolic disorders. Accumulating evidence indicates that the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome results in the activation of pyroptosis and inflammation. Current evidence suggests that pyroptosis-dependent cell death plays a progressive role in the development of diabetic complications including diabetic wound healing (DWH) and diabetic foot ulcers (DFUs). This review presents a brief overview of the molecular mechanisms underlying pyroptosis and addresses the current research on pyroptosis-dependent signaling pathways in the context of DWH. In this review, we also present some prospective therapeutic compounds/agents that can target pyroptotic signaling pathways, which may serve as new strategies for the effective treatment and management of diabetic wounds.Keywords: diabetes mellitus, diabetic wound healing, pyroptosis, NLRP3, caspase-1, GSDMD, inflammation, inflammasome

Myocardial necrosis following the successful reperfusion of a coronary artery occluded by thrombus in a patient presenting with ST-elevation myocardial infarction (STEMI) continues to be a serious problem, despite the multiple attempts to attenuate the necrosis with agents that have shown promise in pre-clinical investigations. Possible reasons include confounding clinical risk factors, the delayed application of protective agents, poorly designed pre-clinical investigations, the possible effects of routinely administered agents that might unknowingly already have protected the myocardium or that might have blocked protection, and the biological differences of the myocardium in humans and experimental animals. A better understanding of the pathobiology of myocardial infarction is needed to stem this reperfusion injury. P2Y12 receptor antagonists minimize platelet aggregation and are currently part of the standard treatment to prevent thrombus formation and propagation in STEMI protocols. Serendipitously, these P2Y12 antagonists also dramatically attenuate reperfusion injury in experimental animals and are presumed to provide a similar protection in STEMI patients. However, additional protective agents are needed to further diminish reperfusion injury. It is possible to achieve additive protection if the added intervention protects by a mechanism different from that of P2Y12 antagonists. Inflammation is now recognized to be a critical factor in the complex intracellular response to ischemia and reperfusion that leads to tissue necrosis. Interference with cardiomyocyte inflammasome assembly and activation has shown great promise in attenuating reperfusion injury in pre-clinical animal models. And the blockade of the executioner protease caspase-1, indeed, supplements the protection already seen after the administration of P2Y12 antagonists. Importantly, protective interventions must be applied in the first minutes of reperfusion, if protection is to be achieved. The promise of such a combination of protective strategies provides hope that the successful attenuation of reperfusion injury is attainable. [ABSTRACT FROM AUTHOR]

Background: There is limited data regarding the hazardous effect of gentamicin (GM) on the uterus and whether or not vinpocetine (Vinpo) ameliorates it. The present study aimed to identify the possible protective effect of Vinpo in GM-induced uterine injury in rats. Methods: Female rats were assorted in control-group, Vinpo-group, GM-group, and Vinpo plus GM group. Serum and uterine GM concentration were measured. Uterine oxidative stress parameters besides inflammatory and apoptotic biomarkers were evaluated. Uterine histopathological examination and interlukin-1beta (IL-1β) immune-histochemical study were detected. Results: GM significantly increased uterine oxidative stress, inflammatory and apoptotic biomarkers. Histopathological picture of uterine damage and increased IL-1β immunoexpression were detected. Vinpo significantly ameliorated the distributed GM concentration, oxidative stress, inflammatory and apoptotic biomarkers with a prompt improvement in histopathological picture and a decrease in IL-1β immunoexpression. Conclusion: Vinpo protective effect against GM-induced uterine injury involves modulation of inflammasome/caspase-1/IL-1β signaling pathway. [ABSTRACT FROM AUTHOR]

Objective To compare the effectiveness between qPCR and trace-level proteins quantitative analysis in detecting the expression of inflammation-associated factors caspase-1 and IL-1β in peripheral blood monocytes from breast cancer patients. Methods Pre- and post-operation peripheral blood samples were collected from 10 breast cancer patients. Monocytes were subsequently isolated and activated by incubation with lipopolysaccharide. The mRNA and protein expression level of caspase-1 and IL-1β in monocytes were examined using qPCR and trace-level proteins quantitative analysis, respectively, and the data were normalized by β-actin. The differences between the two detection methods were compared and evaluated for strengthens and weakness. Results The vast majority of patients showed a notable increase in the number of peripheral blood monocytes after surgical operation. At the mRNA level, compared to preoperative levels, postoperative caspase-1 and IL-1β were both increased in 50% (5/10) and 40% (4/10) of patients, respectively, while the rest showed either a decrease (40% and 50%, respectively) or no significant change (both 10%). In contrast, the results of trace-level proteins quantitative analysis revealed that 60% (6/10) of patients exhibited increased level of postoperative caspase-1 and IL-1β proteins, while the remaining showed a decrease (30% and 20%, respectively) or no significant change (10% and 20%, respectively). Additionally, 50% of patients displayed a significant increase in caspase-1 and IL-1β active cleavage bands by electrophoresis postoperatively. Notably, inconsistent changes in caspase-1 and IL-1β mRNA and protein level after surgery were observed in 30% and 40% of patients respectively. Conclusions The trace-level proteins quantitative analysis is recommended due to its advantages including minimal sample amount requirement, high sensitivity, good repeatability and relatively simple operative procedure. Therefore, it is particularly suitable for assessing the inflammatory status of of patients through clinical sampling of peripheral blood. [ABSTRACT FROM AUTHOR]

Objective: Loss of occlusal support due to tooth loss has been indicated as one of the risk factors for Alzheimer's disease. This study aimed to investigate the relationship between tooth loss and cognitive dysfunction and illustrate the role of neuroinflammation in advancing Alzheimer's disease. Materials and Methods: Male 5‐month‐old senescence‐accelerated mouse strain P8 (SAMP8) mice were divided into three groups (n = 7): the C (control), S (sham‐operated), and TL (tooth loss) groups. The Morris water maze (MWM) test was performed to assess spatial memory. Additionally, histopathological and molecular assessments of hippocampal tissues were performed. Results: The TL groups exhibited impaired spatial memory in the water maze. Tooth loss induced higher protein expression levels of the neuroinflammation cytokine interleukin‐1β (IL‐1β) in the hippocampus than in the S and C groups. Tooth loss activated the NLRP3 inflammasome and increased the expression of Caspase‐1 in the hippocampus. Conclusions: The findings indicated that tooth loss impairs cognitive function in SAMP8 mice and is closely related to the activation of NLRP3/Caspase‐1 in the hippocampus. [ABSTRACT FROM AUTHOR]

Objective To investigate the expression and role of melanoma 2 (AIM2), Caspase-1 and gasdermin D (GSDMD) in the pathogenesis of acute gouty arthritis (AGA). Methods Clinical data, biochemical indices and blood samples were collected from 30 patients with AGA (the AGA group) and 30 healthy volunteers (the HC group). Blood cell analyzer was used to detect serum white blood cell count (WBC), hemoglobin (Hb) and platelet count (PLT). Automatic biochemical analyzer was used to detect fasting blood glucose (FBG), blood uric acid (UA), triacylglycerol (TG), total cholesterol (TC), alaine transaminase (ALT), aspartate transaminase (AST), serum creatinine (Scr), blood urea nitrogen (BUN), creatinine clearance rate (Ccr), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. Fluorescence quantitative assay was used to measure serum level of double-stranded DNA (dsDNA). Western blot was performed to detect the relative protein expression levels of AIM2, Caspase-1, GSDMD, interleukin-1β (IL-1β) and IL-18 in peripheral blood mononuclear cells (PBMCs). Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of IL-1β and IL-18. Results Compared with the HC group, the AGA group showed increased levels of blood biochemical indicators, including WBC, PLT, ESR, CRP, UA, TC, TG, Scr and Ccr (P＜0.05). The serum levels of dsDNA, IL-1β and IL-18 were also increased in the AGA group. Furthermore, the relative protein expression levels of AIM2, Caspase-1, GSDMD, IL-1β and IL-18 in PBMCs were all increased (P＜0.05). In PBMCs, the protein expression level of AIM2 was positively correlated with that of Caspase-1, GSDMD, IL-1β and IL-18 (r or rs values were 0.965, 0.986, 0.928 and 0.737, respectively, all P＜0.01). Conclusion The expression of AIM2 inflammasome-mediated pyroptosis pathway related molecules (AIM2/Caspase-1/GSDMD) is increased in AGA, which may be involved in the immune inflammatory response of AGA. [ABSTRACT FROM AUTHOR]

The endoplasmic reticulum (ER) is determinant to maintain cellular proteostasis. Upon unresolved ER stress, this organelle activates the unfolded protein response (UPR). Sustained UPR activates is known to occur in inflammatory processes, deeming the ER a potential molecular target for the treatment of inflammation. This work characterizes the inflammatory/UPR-related molecular machinery modulated by an in-house library of natural products, aiming to pave the way for the development of new selective drugs that act upon the ER to counter inflammation-related chronic diseases. Starting from a library of 134 compounds of natural occurrence, mostly occurring in medicinal plants, nontoxic molecules were screened for their inhibitory capacity against LPS-induced nuclear factor kappa B (NF-κB) activation in a luciferase-based reporter gene assay. Since several natural products inhibited NF-κB expression in THP-1 macrophages, their effect on reactive oxygen species (ROS) production and inflammasome activation was assessed, as well as their transcriptional outcome regarding ER stress. The bioactivities of several natural products are described herein for the first time. We report the anti-inflammatory potential of guaiazulene and describe 5-deoxykaempferol as a novel inhibitor of inflammasome activation. Furthermore, we describe the dual potential of 5-deoxykaempferol, berberine, guaiazulene, luteolin-4'-O-glucoside, myricetin, quercetagetin and sennoside B to modulate inflammatory signaling ER stress. Our results show that natural products are promising molecules for the discovery and pharmaceutical development of chemical entities able to modulate the inflammatory response, as well as proteostasis and the UPR. [ABSTRACT FROM AUTHOR]

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders affecting the digestive tract, including ulcerative colitis and Crohn's disease. Ruscogenin, a prominent steroidal sapogenin present in radix ophiopogon japonicus, has shown a protective effect on attenuating the inflammatory response associated with inflammatory diseases, but the efficacy of ruscogenin in IBD remains unclear. The aim of this study is to explore the effect of ruscogenin on intestinal barrier dysfunction and inflammatory responses as well as the underlying mechanism in ulcerative colitis. A dextran sulfate sodium salt (DSS)-induced C57BL/6 mouse colitis model was employed for the in vivo studies, while in vitro experiments were performed in THP-1 cells and human intestinal epithelial cells involved in inducing inflammatory responses and pyroptosis using LPS/nigericin. The results indicated that ruscogenin treatment attenuated the symptoms of ulcerative colitis, reduced the release of inflammatory cytokines and the expression of pyroptosis-associated proteins, and restored the integrity of the intestinal epithelial barrier in colon tissue in mice. Moreover, ruscogenin inhibited LPS/nigericin-induced pyroptosis in THP-1 cells. Mechanically, ruscogenin inhibited NLRP3 inflammasome activation and canonical pyroptosis, at least in part, through the suppression of the TLR4/NF-κB signaling pathway. These findings might provide new insights and a solid foundation for further exploration into the therapeutic potential of ruscogenin in the treatment of IBD. [ABSTRACT FROM AUTHOR]