Shikonin from lithospermum erythrorhizon induces pyroptosis in trophoblast cells by activating the CTSB-NLRP3 inflammasome.

BACKGROUND: With the decline of global fertility, drug therapeutic of ectopic pregnancy is of great significance. Lithospermum erythrorhizon is using for embryo killing as herbal medicine. Shikonin is the critical nucleus of Lithospermum erythrorhizon; however, the mechanism is still unclear. The study aimed to explore the mechanism of shikonin against ectopic pregnancy. MATERIAL AND METHODS: In this study, we examined the viability and LDH release of HTR-8/SVneo cells by assays, observed pore formation in cell membranes by microscopy imaging and PI staining, and IL-1ß release by WB and ELISA assay kit. Then, we used network pharmacology to analyse the potential interaction between shikonin, ectopic pregnancy and pyroptosis and used molecular docking techniques to verify interactions between shikonin and core common targets. Finally, western blotting and immunofluorescence assay were used to explore the mechanism of shikonin-inducing pyroptosis of HTR-8/SVneo cells. RESULTS: Shikonin could cause a significant inhibition of HTR-8/SVneo cell viability in a concentration- and time-dependent manner. In HTR-8/SVneo cells, shikonin-induced cell swelling, bubble formation, an increase in the release of lactate dehydrogenase (LDH) and up-regulation of several pyroptosis-associated factors. And network pharmacology showed that The main targets of shikonin-ectopic pregnancy-pyroptosis were IL-1ß and caspase-1, and molecular docking results showed that shikonin can closely bind to IL-1ß, caspase-1 and GSDMD. Additionally, the necroptosis inhibitor GSK'872 could not suppress the expression of mature-IL-1ß and prevent the pyroptosis phenotype from developing. However, the nucleotide oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inhibitor MCC-950 could downregulate the expression of pyroptosis-associated factors and prevent the pyroptosis phenotype from developing. Shikonin led to an elevation in the expression of cathepsin B (CTSB), and the CTSB inhibitor CA-074 abolished pyroptosis induced by shikonin; however, the NLRP3 inhibitor MCC-950 could not inhibit the expression of CTSB. CONCLUSIONS: Our results suggest that shikonin activates CTSB to induce NLRP3-dependent pyroptosis in HTR-8/SVneo cells. This study has important clinical implications for the treatment of ectopic pregnancy.

Bitongqing Attenuates CIA Rats by Suppressing Macrophage Pyroptosis and Modulating the NLRP3/Caspase-1/GSDMD Pathway.

Background: Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovitis and inflammatory cell infiltration. The traditional Chinese medicine prescription, Bitongqing (BTQ) exhibited significant efficacy in the clinical treatment of RA. However, the potential therapeutic mechanisms of BTQ in treating RA have not been fully investigated. This study aims to elucidate the effect of BTQ on collagen-induced arthritis (CIA) rat macrophage pyroptosis, providing a theoretical basis for treating RA. Methods: This research employed liquid chromatography-mass spectrometry (LC-MS) to identify the primary components of BTQ. The therapeutic effects of BTQ were evaluated in a rat model of CIA. In vivo experiments were conducted using pathohistological staining, immunofluorescence, micro-CT, and Western blotting. Next, Mouse leukemia cells of monocyte macrophage cells (RAW264.7) were induced to undergo pyroptosis using lipopolysaccharide (LPS) and adenosine triphosphate (ATP), and the impact of BTQ on RAW264.7 macrophages was assessed through cell viability, immunofluorescence analysis, lactate dehydrogenase (LDH) secretion measurement, and Western blotting. Results: BTQ had a therapeutic effect on CIA rats, which was mainly manifested as a reduction in joint inflammation, foot swelling, bone erosion, and amelioration of pathological changes in these rats. Further studies revealed that BTQ inhibited the levels of cytokine production interleukin-18 (IL-18) and interleukin-1ß (IL-1ß), and likewise, it inhibited the expression of key proteins in the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) mediated pyroptosis in the synovial tissues of CIA rats. The results of in vitro experiments demonstrated that BTQ attenuated LDH secretion, decreased IL-18 and IL-1ß cytokine production, and downregulated expression of key proteins involved in the NLRP3-mediated pyroptosis on RAW264.7 macrophages. Conclusion: The therapeutic potential of BTQ in CIA lies in its ability to inhibit NLRP3-mediated macrophage pyroptosis, thereby suggesting a promising strategy for the treatment of RA.

Therapeutic effect of Sheng Mai San, a traditional Chinese medicine formula, on inflammatory bowel disease via inhibition of NF-κB and NLRP3 inflammasome signaling.

Introduction: Inflammatory bowel disease (IBD) is a globally emergent chronic inflammatory disease which commonly requires lifelong care. To date, there remains a pressing need for the discovery of novel anti-inflammatory therapeutic agents against this disease. Sheng Mai San (SMS) is a traditional Chinese medicine prescription with a long history of use for treating Qi and Yin deficiency and recent studies have shown that SMS exhibits anti-inflammatory potential. However, the effects of SMS on the gastrointestinal system remain poorly studied, and its therapeutic potential and underlying molecular mechanisms in IBD have yet to be discovered. In this study, we examined the therapeutic efficacy of SMS in IBD and its anti-inflammatory activity and underlying molecular mechanism, in vivo and in vitro. Methods: The therapeutic efficacy of SMS in IBD was assessed in the DSS-induced acute colitis mouse model. Body weight, stool consistency, rectal bleeding, colon length, organ coefficient, cytokine levels in colon tissues, infiltration of immune cells, and colon pathology were evaluated. The anti-inflammatory activity of SMS and related molecular mechanisms were further examined in lipopolysaccharide (LPS)-induced macrophages via assessment of pro-inflammatory cytokine secretion and NF-κB, MAPK, STAT3, and NLRP3 signalling. Results: SMS significantly ameliorated the severity of disease in acute colitis mice, as evidenced by an improvement in disease activity index, colon morphology, and histological damage. Additionally, SMS reduced pro-inflammatory cytokine production and infiltration of immune cells in colon tissues. Furthermore, in LPS-induced macrophages, we demonstrated that SMS significantly inhibited the production of cytokines and suppressed the activation of multiple pro-inflammatory signalling pathways, including NF-κB, MAPK, and STAT3. SMS also abolished NLRP3 inflammasome activation and inhibited subsequent caspase-1 activation and IL-1ß secretion, suggesting a new therapeutic target for the treatment of IBD. These mechanistic findings were also confirmed in in vivo assays. Conclusion: This study presents the anti-inflammatory activity and detailed molecular mechanism of SMS, in vitro and in vivo. Importantly, we highlight for the first time the potential of SMS as an effective therapeutic agent against IBD.

NLRP3 and autophagy in retinal ganglion cell inflammation in age-related macular degeneration: potential therapeutic implications.

Retinal degenerative diseases were a large group of diseases characterized by the primary death of retinal ganglion cells (RGCs). Recent studies had shown an interaction between autophagy and nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasomes, which may affect RGCs in retinal degenerative diseases. The NLRP3 inflammasome was a protein complex that, upon activation, produces caspase-1, mediating the apoptosis of retinal cells and promoting the occurrence and development of retinal degenerative diseases. Upregulated autophagy could inhibit NLRP3 inflammasome activation, while inhibited autophagy can promote NLRP3 inflammasome activation, which leaded to the accelerated emergence of drusen and lipofuscin deposition under the neurosensory retina. The activated NLRP3 inflammasome could further inhibit autophagy, thus forming a vicious cycle that accelerated the damage and death of RGCs. This review discussed the relationship between NLRP3 inflammasome and autophagy and its effects on RGCs in age-related macular degeneration, providing a new perspective and direction for the treatment of retinal diseases.

Magnesium-enriched deep-sea water inhibits NLRP3 inflammasome activation and dampens inflammation.

The NLRP3 inflammasome is an essential component of the innate immune system, but excessive activation can lead to inflammatory diseases. Ion fluxes across the plasma membrane or from intracellular stores are known to regulate NLRP3 inflammasome activation. Deep-sea water (DSW) contains high concentrations of many mineral ions, which could potentially influence NLRP3 inflammasome activation. However, the impact of DSW on NLRP3 inflammasome activation has not been investigated. Here, we demonstrated that DSW with water hardness levels up to 500 mg/L did not affect cell viability or the expression of NLRP3 inflammasome components in macrophages derived from THP-1 cells. However, the DSW significantly inhibited IL-1ß secretion and caspase-1 activation in response to NLRP3 activators such as nigericin, ATP, or monosodium urate (MSU) crystals. Mechanically, it was discovered that the presence of 5 mM magnesium ions (Mg2+), equivalent to the Mg2+ concentration found in the DSW with a water hardness of 500 mg/L, inhibits NLRP3 inflammasome activation. This indicates that Mg2+ contributes to the mechanism by which DSW mitigates NLRP3 inflammasome activation. Moreover, DSW administration effectively lessens MSU-triggered peritonitis in mice, a commonly used model for examining the impacts of NLRP3 inflammasome activation. These results show that DSW enriched with Mg2+ could potentially be beneficial in modulating NLRP3 inflammasome-associated diseases.

NLRP3 inflammasome inhibition decreases Schistosomiasis japonica-induced granulomatous inflammation and fibrosis in BALB/c mice.

To research the role of the NLRP3 inflammasome in Schistosoma japonicum-induced granuloma formation and liver fibrosis. In in vivo tests, BALB/c mice were used. shNLRP3 plasmid based on adeno-associated virus serotype 8 (AAV8-shNLRP3) was injected to block NLRP3 inflammasome via tail vein. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were detected to assess liver injury. H&E staining was used for routine histopathological assessment; Masson's trichrome staining was used to detect fibrous tissues and collagen fibers. Hepatic expression of NLRP3, procaspase-1, bioactive caspase-1, collagen-1, tissue inhibitor of metalloproteinases-1 (TIMP-1), and α-smooth muscle actin (α-SMA) were detected by western blot. Serum levels of IL-1ß were detected by enzyme-linked immunosorbent assay (ELISA). The inflammatory cell infiltration and hepatic expression of IL-1ß around the granuloma were detected by immunohistochemistry staining. Treatment of S. japonicum infected mice with AAV8-shNLRP3 significantly reduced the hepatic levels of bioactive caspase-1 and IL-1ß, as well as circulating IL-1ß concentrations, while reducing the amounts of myeloperoxidase (MPO) and F4/80 positive cells around the granuloma. Moreover, collagen deposition, TIMP-1, and α-SMA, which are markers of hepatic stellate cell (HSC) activation, were reduced around the liver granuloma. These findings highlight a therapeutic potential of AAV8-shNLRP3 in schistosomiasis cirrhosis.

Synthesis and Biological Evaluation of Novel Chlorogenic Acid-Apigenin Conjugates as Anti-acute Gout Agents.

Gout is the second largest metabolic disease worldwide after diabetes, with acute gouty arthritis as most common symptom. Xanthine oxidase (XOD) and the NOD like receptor-3 (NLRP3) inflammasome are the key targets for acute gout treatment. Chlorogenic acid has been reported with a good anti-inflammatory activity, and Apigenin showed an excellent potential in XOD inhibition. Therefore, a series of chlorogenic acid-apigenin (CA) conjugates with varying linkers were designed and synthesized as dual XOD/NLRP3 inhibitors, and their activities both in XOD and NLRP3 inhibition were evaluated. An in vitro study of XOD inhibitory activity revealed that the majority of CA conjugates exhibited favorable XOD inhibitory activity. Particularly, the effects of compounds 10c and 10d, with an alkyl linker on the apigenin moiety, were stronger than that of allopurinol. The selected CA conjugates also demonstrated a favorable anti-inflammatory activity in RAW264.7 cells. Furthermore, compound 10d, which showed the optimal activity both in XOD inhibition and anti-inflammatory, was chosen and its inhibitory ability on NLRP3 and related proinflammatory cytokines was further tested. Compound 10d effectively reduced NLRP3 expression and the secretion of interluekin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) with an activity stronger than the positive control isoliquiritigenin (ISL). Based on these findings, compound 10d exhibits dual XOD/NLRP3 inhibitory activity and, therefore, the therapeutic effects on acute gout is worthy of further study.

Rutin Ameliorates Inflammation and Oxidative Stress in Ulcerative Colitis by Inhibiting NLRP3 Inflammasome Signaling Pathway.

Ulcerative colitis (UC) is an idiopathic inflammatory disease. We intend to explore the mechanism of Rutin in the therapy of UC. Disease activity index (DAI) and hematoxylin-eosin staining were employed to assess therapeutic effect of Rutin on dextran sulfate sodium-stimulated mice. The proliferation was detected by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. Oxidative stress (OS) was assessed by measuring reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD). Inflammatory factors were detected using enzyme-linked immunosorbent assay and immunofluorescence staining. mRNA and protein expressions were detected by real-time quantitative polymerase chain reaction and immunoblotting assay. Rutin decreased DAI scores and ameliorated pathological damage in UC mice with decreased levels of inflammatory factors. Rutin recovered the inhibited proliferation of fetal human colon cells caused by lipopolysaccharide. Rutin inhibited OS by reducing ROS and MDA, while enhancing SOD activity in LPS-induced fetal human colon cells. Rutin inhibited NLRP3 inflammasome in UC mice and cell model. Silencing NLRP3 enhanced the inhibitory effect of Rutin on OS in lipopolysaccharide-induced fetal human colon cells. Conversely, NLRP3 overexpression reversed the restraining role of Rutin in OS. Rutin ameliorates UC by inhibiting inflammation and OS through suppressing NLRP3 inflammasome.

GDF11 protects against mitochondrial-dysfunction-dependent NLRP3 inflammasome activation to attenuate osteoarthritis.

INTRODUCTION: Osteoarthritis (OA) is a highly prevalent degenerative disease worldwide, and tumor necrosis factor (TNF-α) is closely associated with its development. Growth differentiation factor 11 (GDF11) has demonstrated anti-injury and anti-aging abilities in certain tissues; however, its regulatory role in OA remains unclear and requires further investigation. OBJECTIVES: To identify whether GDF11 can attenuate osteoarthritis. To exploring the the potential mechanism of GDF11 in alleviating osteoarthritis. METHODS: In this study, we cultured and stimulated mouse primary chondrocytes with or without TNF-α, analyzing the resulting damage phenotype through microarray analysis. Additionally, we employed GDF11 conditional knockout mice OA model to examine the relationship between GDF11 and OA. To investigate the target of GDF11's function, we utilized NLRP3 knockout mice and its inhibitor to verify the potential involvement of the NLRP3 inflammasome. RESULTS: Our in vitro experiments demonstrated that endogenous overexpression of GDF11 significantly inhibited TNF-α-induced cartilage matrix degradation and inflammatory expression in chondrocytes. Furthermore, loss of GDF11 led to NLRP3 inflammasome activation, inflammation, and metabolic dysfunction. In an in vivo surgically induced mouse model, intraarticular administration of recombinant human GDF11 alleviated OA pathogenesis, whereas GDF11 conditional knockout reversed this effect. Additionally, findings from the NLRP3-knockout DMM mouse model revealed that GDF11 exerted its protective effect by inhibiting NLRP3. CONCLUSION: These findings demonstrate the ability of GDF11 to suppress TNF-α-induced inflammation and cartilage degeneration by preventing mitochondrial dysfunction and inhibiting NLRP3 inflammasome activation, suggesting its potential as a promising therapeutic drug for osteoarthritis.

MIF aggravates experimental autoimmune prostatitis through activation of the NLRP3 inflammasome via the PI3K/AKT pathway.

In our investigation, we investigated the role of macrophage migration inhibitory factor (MIF), a key cytokine, in chronic nonbacterial prostatitis (CNP), an underexplored pathology. Elevated MIF expression was observed in the serum of individuals with chronic prostatitis-like symptoms (CP-LS) as well as in serum and tissue samples from experimental autoimmune prostatitis (EAP) mouse model. Treatment with ISO-1, a specific MIF antagonist, effectively mitigated prostatic inflammation and macrophage infiltration, thereby emphasizing the critical role of MIF in orchestrating immune responses within the prostate microenvironment. Further analyses revealed that MIF stimulates the PI3K/AKT and NLRP3 inflammasome pathways, which are integral to inflammation and cellular immunity. Pharmacological inhibition of the PI3K/AKT pathway by LY294002 substantially reduced prostatic inflammation and macrophage infiltration, potentially by inhibiting NLRP3 inflammasome activation. These findings collectively suggest that MIF is a potential diagnostic marker for CNP and suggest that targeting MIF or its downstream signalling pathways, PI3K/AKT and NLRP3, might represent a novel therapeutic strategy for this condition.

Modulating the HSP90 control over NFκB/NLRP3/Caspase-1 axis is a new therapeutic target in the management of liver fibrosis: Insights into the role of TAS-116 (Pimitespib).

Aberrant activation of the NLRP3 inflammasome is recognized to induce a chronic inflammatory response in the liver, ultimately leading to hepatic fibrosis. HSP90 is suggested to regulate NLRP3 activation and its downstream signaling. This study is the first to explore the potential therapeutic role of pimitespib in mitigating liver fibrosis in rats. The results of the study revealed that pimitespib effectively suppressed hepatic inflammation and fibrogenesis by modulating HSP90's control over the NFκB/NLRP3/caspase-1 axis. In vitro experiments demonstrated that pimitespib reduced LDH levels and increased hepatocyte survival, whereas in vivo, it prolonged the survival of rats with hepatic fibrosis. Additionally, pimitespib exhibited improvements in the function and microscopic characteristics of rat livers. Pimitespib effectively inhibited NFκB, which serves as the priming signal for NLRP3 activation. Pimitespib's inhibitory effect on NLRP3, identified as an HSP90 client protein, plays a central role in the observed anti-fibrotic effect. The simultaneous inhibition of both priming and activation signals of NLRP3 by pimitespib led to a reduction in caspase-1 activity and subsequent suppression of the N-terminal fragment of gasdermin D, ultimately constraining hepatocyte pyroptotic cell death. These diverse effects were associated with a decrease in the transcription of inflammatory mediators IL-1ß, IL-18, and TNF-α, as well as the fibrogenic mediators TGF-ß, TIMP-1, PDGF-BB, and Col1a1. Moreover, pimitespib induced the expression of HSP70, which could further contribute to the repression of fibrosis development. In summary, our findings provide an evolutionary perspective on managing liver fibrosis, positioning pimitespib as a promising candidate for anti-inflammatory and antifibrotic therapy.

The Coptidis Rhizoma and Bovis Calculus herb pair attenuates NASH and inhibits the NLRP3 inflammasome activation.

The Coptidis Rhizoma and Bovis Calculus herb pair possesses clearing heat and detoxifying effects. The aim of this study was to reveal the effects and mechanisms of the herb pair in the treatment of NASH by network pharmacology and experimental verification. A network pharmacology-based approach was employed to predict the putative mechanism of the herb pair against NASH. The high-fat diet (HFD) and methionine/choline deficient (MCD) diet induced NASH models were used to evaluate efficacy and mechanism of the herb pair. Network pharmacological analysis showed that the herb pair modulated NOD-like receptor pathway. In the HFD mice, herb pair reduced body weight, blood sugar, serum ALT, AST, TBA, TC, TG and LDL-C contents, also improved the general morphology and pathological manifestations. Hepatic transcriptomics study showed that herb pair attenuated NASH by regulating NOD-like receptor signaling pathway. Western blotting showed that herb pair reduced the protein expression levels of NLRP3, cleaved Caspase-1 and cleaved IL-1ß. In the MCD mice, herb pair also reduced serum ALT, ALT and TBA levels, improved liver pathological manifestations, inhibited the protein expression levels of NLRP3, cleaved Caspase-1 and cleaved IL-1ß. Our findings proved that the Coptidis Rhizoma and Bovis Calculus herb pair attenuates NASH through suppression of NLRP3 inflammasome activation. This will demonstrate effective pharmacological evidence for the clinical application of herb pair.

Novel genetic variants in the NLRP3 inflammasome-related PANX1 and APP genes predict survival of patients with hepatitis B virus-related hepatocellular carcinoma.

BACKGROUND: The nod-like receptor protein 3 (NLRP3) is one of the most characterized inflammasomes involved in the pathogenesis of several cancers, including hepatocellular carcinoma (HCC). However, the effects of genetic variants in the NLRP3 inflammasome-related genes on survival of hepatitis B virus (HBV)-related HCC patients are unclear. METHODS: We performed multivariable Cox proportional hazards regression analysis to evaluate associations between 299 single-nucleotide polymorphisms (SNPs) in 16 NLRP3 inflammasome-related genes and overall survival (OS) of 866 patients with HBV-related HCC. We further performed expression quantitative trait loci (eQTL) analysis using the data from the GTEx project and 1000 Genomes projects, and performed differential expression analysis using the TCGA dataset to explore possible molecular mechanisms underlying the observed associations. RESULTS: We found that two functional SNPs (PANX1 rs3020013 A > G and APP rs9976425 C > T) were significantly associated with HBV-related HCC OS with the adjusted hazard ratio (HR) of 0.83 [95% confidence interval (CI) = 0.73-0.95, P = 0.008], and 1.26 (95% CI = 1.02-1.55, P = 0.033), respectively. Moreover, the eQTL analysis revealed that the rs3020013 G allele was correlated with decreased mRNA expression levels of PANX1 in both normal liver tissues (P = 0.044) and whole blood (P < 0.001) in the GTEx dataset, and PANX1 mRNA expression levels were significantly higher in HCC samples and associated with a poorer survival of HCC patients. However, we did not observe such correlations for APP rs9976425. CONCLUSIONS: These results indicated that SNPs in the NLRP3 inflammasome-related genes may serve as potential biomarkers for HBV-related HCC survival, once replicated by additional larger studies.

An integrated network pharmacology and molecular docking approach to reveal the role of Arctigenin against Cutibacterium acnes-induced skin inflammation by targeting the CYP19A1.

Acne caused by inflammation of hair follicles and sebaceous glands is a common chronic skin disease. Arctigenin (ATG) is an extract of Arctium lappa L., which has significant anti-inflammatory effects. However, the effect and mechanism of ATG in cutaneous inflammation mediated by Cutibacterium acnes (C. acnes) has not been fully evaluated. The purpose of this study was to explore the effect and potential mechanism of ATG in the treatment of acne through network pharmacology and experimental confirmation. An acne model was established by injected live C. acnes into living mice and treated with ATG. Our data showed that ATG effectively improved acne induced by live C. acnes, which was confirmed by determining ear swelling rate, estradiol concentration and hematoxylin and eosin (H&E) staining. In addition, ATG inhibited the NLRP3 inflammasome signaling pathway in mice ear tissues and reduced the secretion of pro-inflammatory cytokines IL-1ß to relieve inflammation. The results of network pharmacology and molecular docking confirmed that ATG can regulate 17ß-Estradiol (E2) levels through targeted to CYP19A1, and finally inhibited skin inflammation. Taken together, our results confirmed that ATG regulated E2 secretion by targeting CYP19A1, thereby inhibiting the NLRP3 inflammasome signaling pathway and improving inflammation levels in acne mice. This study provides a basis for the feasibility of ATG in treating acne in clinical practice.

Exploring the role of NLRP3 inflammasome in diabetic nephropathy and the advancements in herbal therapeutics.

Diabetic nephropathy (DN), a prevalent complication of diabetes mellitus (DM), is clinically marked by progressive proteinuria and a decline in glomerular filtration rate. The etiology and pathogenesis of DN encompass a spectrum of factors, including hemodynamic alterations, inflammation, and oxidative stress, yet remain incompletely understood. The NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome, a critical component of the body's innate immunity, plays a pivotal role in the pathophysiology of DN by promoting the release of inflammatory cytokines, thus contributing to the progression of this chronic inflammatory condition. Recent studies highlight the involvement of the NLRP3 inflammasome in the renal pathology associated with DN. This article delves into the activation pathways of the NLRP3 inflammasome and its pathogenic implications in DN. Additionally, it reviews the therapeutic potential of traditional Chinese medicine (TCM) in modulating the NLRP3 inflammasome, aiming to provide comprehensive insights into the pathogenesis of DN and the current advancements in TCM interventions targeting NLRP3 inflammatory vesicles. Such insights are expected to lay the groundwork for further exploration into TCM-based treatments for DN.

[Changes and clinical significance of NLRP3 inflammasomes and related factors in patients with spinal fracture complicated with acute spinal cord injury].

OBJECTIVE: To investigate the changes and clinical significance of NOD like receptor protein 3 (NLRP3) inflammasomes and related factors in patients with spinal fractures complicated with acute spinal cord injury (SCI). METHODS: Eighty-six spinal fracture patients complicated with acute SCI admitted to hospital from June 2019 to March 2022 were selected as SCI group, There were 48 males and 38 females, with an average age of (43.48±6.58) years old. And 100 healthy volunteers who underwent physical examination during the same time were selected as control group, including 56 males patients and 44 females patients, with an average age of (45.13±6.43) years old. Peripheral blood mononuclear cell (PBMC) were collected, and the mRNA expressions of NLRP3 and Caspase-1 were detected. Serum was collected and the levels of interleukin (IL)- 1ß, IL-18 were detected. According to Frankel's grade, the SCI group was divided into complete injury patients and incomplete injury patients, and according to the Japanese Orthopedic Society (JOA) grade, the SCI group was divided into good prognosis group and poor prognosis group. The difference of NLRP3, Caspase-1, IL-1ß, IL-18 among groups were compared, the influencing factors for poor prognosis in SCI patients was analyzed by Logistic regression. RESULTS: The mRNA expression levels of NLRP3 (1.41±0.33) and Caspase-1 (1.44±0.35) in PBMC and the levels of IL-1ß(45.34±13.22) pg·ml-1, IL-18(40.95±8.77) pg·ml-1 in serum of SCI group were higher than those of the control group[(1.00±0.19), (1.00±0.16), (16.58±4.24) pg·ml-1, (12.57±3.68) pg·ml-1] (P<0.05). The mRNA expression levels of NLRP3(1.63±0.34) and Caspase-1 (1.67±0.27) in PBMC and the levels of IL-1ß(51.09±11.10) pg·ml-1, IL-18 (47.65±7.93) pg·ml-1 in serum of patients with complete injury in the SCI group were higher than those of patients with incomplete injury [(1.31±0.27), (1.34±0.33), (42.85±13.36) pg·ml-1, (38.05±7.48) pg·ml-1](P<0.05). The mRNA expression levels of NLRP3 (1.66±0.31) and Caspase-1 (1.72±0.31)in PBMC and the levels of IL-1ß(51.21±11.31) pg·ml-1, IL-18 (45.70±7.25) pg·ml-1 in serum, the proportion of complete injury(21 patients), and the proportion of spinal cord edema or bleeding of patients(15 patients) with poor prognosis in the SCI group were higher than those of patients with good prognosis[(1.28±0.26), (1.37±0.36), (42.79±13.25) pg·ml-1、(38.90±8.63) pg·ml-1, 5、20 cases](P<0.05). Complete injury and the mRNA expression of NLRP3 in PBMC were the influencing factors for poor prognosis in the SCI group (P<0.05). CONCLUSION: The activation of NLRP3 inflammasomes in patients with spinal fractures complicated with acute SCI is associated with worsening injury and poor prognosis, and NLRP3 expression can serve as a marker for evaluating prognosis.

Cell death crosstalk in respiratory diseases: unveiling the relationship between pyroptosis and ferroptosis in asthma and COPD.

Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous obstructive diseases characterized by airflow limitations and are recognized as significant contributors to fatality all over the globe. Asthma accounts for about 4, 55,000 deaths, and COPD is the 3rd leading contributor of mortality worldwide. The pathogenesis of these two obstructive disorders is complex and involves numerous mechanistic pathways, including inflammation-mediated and non-inflammation-mediated pathways. Among all the pathological categorizations, programmed cell deaths (PCDs) play a dominating role in the progression of these obstructive diseases. The two major PCDs that are involved in structural and functional remodeling in the progression of asthma and COPD are Pyroptosis and Ferroptosis. Pyroptosis is a PCD mechanism mediated by the activation of the Nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome, leading to the maturation and release of Interleukin-1ß and Interleukin-18, whereas ferroptosis is a lipid peroxidation-associated cell death. In this review, the major molecular pathways contributing to these multifaceted cell deaths have been discussed, and crosstalk among them regarding the pathogenesis of asthma and COPD has been highlighted. Further, the possible therapeutic approaches that can be utilized to mitigate both cell deaths at once have also been illustrated.

Naringin safeguards vertebral endplate chondrocytes from apoptosis and NLRP3 inflammasome activation through SIRT3-mediated mitophagy.

AIM: The degradation of the cartilage endplate (CEP) plays a critical role in the initiation and progression of intervertebral disc degeneration (IVDD), a disease closely associated with inflammation and oxidative stress. Naringin (NGN), a flavonoid compound derived from citrus fruits, has been shown to exhibit significant anti-inflammatory and antioxidant properties. This suggests a promising avenue for NGN's application in IVDD therapy. This study aims to elucidate the therapeutic effects and underlying mechanisms of NGN on CEP degeneration, contributing to the formulation of evidence-based treatment strategies for IVDD. METHODS: In vivo, we developed an intervertebral disc degeneration (IVDD) model in mice by excising the bilateral facet joints and surrounding ligaments, and evaluated the effects of naringin using HE staining and Micro-CT analysis. In vitro, endplate chondrocytes were isolated and subjected to TBHP to replicate the IVDD pathological condition. The protective effects of NGN on these cells were confirmed through immunofluorescence, Western Blot, and flow cytometry. RESULTS: In vivo, NGN effectively mitigated IVDD progression and CEP calcification in mice. In vitro, NGN enhanced mitophagy and suppressed NLRP3 inflammasome activation through the SIRT3/FOXO3a/Parkin pathway. Furthermore, NGN safeguarded chondrocytes against apoptosis and calcification triggered by oxidative stress, in addition to mitigating the degradation of the extracellular matrix. However, silencing SIRT3 negated NGN's protective influence on chondrocytes. CONCLUSION: Our study demonstrated that NGN effectively shields chondrocytes from apoptosis and NLRP3 inflammasome activation by facilitating SIRT3-mediated mitophagy. These insights could pave the way for innovative approaches in the prevention and management of IVDD.

LncRNA KCNQ1OT1 promotes NLRP3 inflammasome activation in Parkinson's disease by regulating pri-miR-186/mature miR-186/NLRP3 axis.

Increasing evidence indicated that neuroinflammation was involved in progression of Parkinson's disease (PD). Long noncoding RNAs (lncRNAs) played important roles in regulating inflammatory processes in multiple kinds of human diseases such as cancer diabetes, cardiomyopathy, and neurodegenerative disorders. The mechanisms by which lncRNAs regulated PD related inflammation and dopaminergic neuronal loss have not yet been fully elucidated. In current study, we intended to explore the function and potential mechanism of lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in regulating inflammasome activation in PD. Functional assays confirmed that knockdown of KCNQ1OT1 suppress microglial NLR family pyrin domain containing 3 (NLRP3) inflammasome activation and attenuated dopaminergic neuronal loss in PD model mice. As KCNQ1OT1 located in both cytoplasm and nucleus of microglia, we demonstrated that KCNQ1OT1 promoted microglial NLRP3 inflammasome activation by competitive binding with miR-186 in cytoplasm and inhibited pri-miR-186 mediated NLRP3 silencing through recruitment of DiGeorge syndrome critical region gene 8 (DGCR8) in nucleus, respectively. Our study found a novel lncRNA-pri-miRNA/mature miRNA-mRNA regulatory network in microglia mediated NLRP3 inflammasome activation and dopaminergic neuronal loss, provided further insights for the treatment of Parkinson's disease.

Graphene oxide-decorated microporous sulfonated polyetheretherketone for guiding osteoporotic bone regeneration.

Recent studies have indicated that the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is an ideal therapeutic target for osteoporosis because it affects the differentiation of osteoblasts and osteoclasts. RNA sequencing utilizing multifunctional graphene oxide (GO) nanosheets revealed a correlation between GO nanomaterials and the NLRP3 inflammasome, as well as osteogenic genes in macrophages. This study aimed to construct a bone microenvironment-responsive multifunctional two-dimensional GO coating on the surface of microporous sulfonated polyetheretherketone (SPEEK) via polydopamine modification (SPEEK@PDA-GO). In vitro analysis showed that the SPEEK@PDA-GO implants weakened the STAT3-mediated NLRP3/caspase-1/IL-1ß signaling pathway in macrophages and subsequently prevented the formation of an extracellular inflammatory microenvironment, which is crucial for osteoclastogenesis. SPEEK@PDA-GO displayed significantly higher expression of M2 macrophage markers and osteogenic genes, indicating that the multifunctional GO nanosheets could facilitate bone regeneration via their immunomodulatory properties. The ability of SPEEK@PDA-GO to stimulate new bone formation and block bone loss caused by estrogen loss due to ovariectomy was also analyzed. The findings of this study offer valuable information on the possible involvement of the NLRP3 inflammasome in the interaction between the immune system and bone health in patients with osteoporosis.