Inflammasomes regulate the host response to intracellular pathogens including mycobacteria. We have previously shown that the course of Mycobacterium marinum infection in adult zebrafish (Danio rerio) mimics the course of tuberculosis in human. To investigate the role of the inflammasome adaptor pycard in zebrafish M. marinum infection, we produced two zebrafish knockout mutant lines for the pycard gene with CRISPR/Cas9 mutagenesis. Although the zebrafish larvae lacking pycard developed normally and had unaltered resistance against M. marinum, the loss of pycard led to impaired survival and increased bacterial burden in the adult zebrafish. Based on histology, immune cell aggregates, granulomas, were larger in pycard-deficient fish than in wild-type controls. Transcriptome analysis with RNA sequencing of a zebrafish haematopoietic tissue, kidney, suggested a role for pycard in neutrophil-mediated defence, haematopoiesis and myelopoiesis during infection. Transcriptome analysis of fluorescently labelled, pycard-deficient kidney neutrophils identified genes that are associated with compromised resistance, supporting the importance of pycard for neutrophil-mediated immunity against M. marinum. Our results indicate that pycard is essential for resistance against mycobacteria in adult zebrafish.

Acute respiratory distress syndrome (ARDS) is a severe inflammatory disorder characterized by acute respiratory failure, alveolar barrier dysfunction, edema, and dysregulated alveolar macrophage-mediated pulmonary inflammation. Despite advancements in treatment strategies, the mortality rate in patients with ARDS remains high, ranging from 40-60 %. Current approaches are limited to supportive care, necessitating the exploration of effective therapeutic options such as suppressing broad inflammatory responses. Although Cirsium japonicum leaves possess anti-inflammatory properties, their specific effects on ARDS have not yet been investigated.

The anti-inflammatory activity of Cirsium japonicum extract (CJE) was investigated in a lipopolysaccharide (LPS)-induced ARDS model.

CJE significantly attenuated LPS-induced lung injury, including reduced alveolar wall thickness, inflammatory cell infiltration, proteinaceous debris, and hyaline membranes. Moreover, CJE repressed infiltration of inflammatory cells and pro-inflammatory gene expression in bronchoalveolar lavage fluid. Concordantly, CJE mitigated alveolar macrophage activation, which consequently reduced neutrophil chemoattractic infiltration. Additionally, CJE suppressed NLRP3 and HIF1α expression in the lungs of the ARDS mouse. Similarly, LPS-induced NLRP3 and HIF1α pathway-associated inflammatory and glycolytic gene expressions significantly diminished by CJE in murine alveolar macrophage cell line, MH-S cells, and bone marrow-derived macrophages.

CJE suppressed multiple inflammatory responses through the regulation of NLRP3 and HIF1α signaling-related gene expression in macrophages of LPS-induced ARDS mice. These results suggest that CJE has therapeutic potential for treating patients with ARDS via macrophage regulation.

Myocardial ischemia-reperfusion (I/R) injury stands as a significant contributor to cardiovascular disease. Shengmai-Yin (SMY), a traditional Chinese medicine, is widely used in myocardial infarct treatment. However, the specific mechanism of SMY in treating myocardial I/R injury is currently limited.

The study aimed to investigate the therapeutic efficacy of SMY in addressing myocardial I/R injury and elucidate its specific mechanisms.

The active components of SMY were quantified using Ultra-high performance liquid chromatography-MS/MS (UPLC-MS/MS). Sprague-Dawley (SD) rats were treated with SMY post-I/R model establishment. Cardiac injury was assessed by heart weight to body weight ratio. Left ventricular function and infarct volume were evaluated using ultrasound cardiography and TTC staining. Tissue lesions were examined via hematoxylin-eosin (HE) and Sirius Red staining. Co-Immunoprecipitation (Co-IP) technology explored absent in melanoma 2 (AIM2) and K27 Ubiquitination Modification (K27-Ub) interactions. Immunofluorescence staining detected Apoptosis-associated Speck-like Protein containing a CARD (ASC) and AIM2 co-localization. Adeno-associated Virus (AAV) was used to upregulate AIM2 levels, while Shikonin was used to downregulate AIM2, to explore its roles in SMY's therapeutic effects on I/R injury.

SMY can reduce infarct size and enhance cardiac function. Furthermore, SMY can inhibit tissue fibrosis. Fibrosis markers and proinflammatory factors were reduced after SMY treatment. Serum levels of Lactate Dehydrogenase (LDH) and Creatine Kinase -MB (CK-MB) were also decreased. Mechanistically, SMY inhibits the activation of the AIM2 inflammasome by downregulating the K27 ubiquitination of AIM2. Overexpression of AIM2 reversed the anti-I/R effect of SMY, suggesting that AIM2 plays a crucial role in I/R injury. The AIM2 inhibitor counteracts the therapeutic effect of SMY.

SMY inhibits the K27 ubiquitination modification of AIM2 and inhibits the activation of AIM2 inflammasomes after myocardial I/R injury.

Parkinson's disease is the second most common neurodegenerative disease, characterized by substantial loss of dopaminergic (DA) neurons, the formation of Lewy bodies (LBs) in the substantia nigra, and pronounced neuroinflammation. The nucleotide-binding domain like leucine-rich repeat- and pyrin domain-containing protein 3 (NLRP3) inflammasome is one of the pattern recognition receptors (PRRs) that function as intracellular sensors in response to both pathogenic microbes and sterile triggers associated with Parkinson's disease. These triggers include reactive oxygen species (ROS), misfolding protein aggregation, and potassium ion (K+) efflux. Upon activation, it recruits and activates caspase-1, then processes the pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-18, which mediate neuroinflammation in Parkinson's disease. In this review, we provide a comprehensive overview of NLRP3 inflammasome, detailing its structure, activation pathways, and the factors that trigger its activation. We also explore the pathological mechanisms by which NLRP3 contributes to Parkinson's disease and discuss potential strategies for targeting NLRP3 as a therapeutic approach.

Chlorogenic acid (CGA), a polyphenolic bioactive molecule derived from medicinal plants, is known for its strong antioxidant and anti-inflammatory properties. Previous studies have demonstrated that dietary supplementation with Lonicera japonica extract, rich in CGA, effectively enhances the production performance of lactating dairy cows under heat stress (HS) conditions. However, the molecular mechanisms underlying CGA's protective effects remain unclear. This study aims to elucidate the mechanisms by which CGA alleviates HS-induced oxidative damage in bovine mammary epithelial cells (bMECs), focusing on its pharmacological activity and potential application as a natural therapeutic agent for bovine mammary disorders. The results demonstrated that HS activates the NF-κB and NLRP3 signaling pathways by increasing ROS generation, leading to oxidative stress and inflammatory response in bMECs. CGA mitigates these effects by scavenging intracellular ROS, activating the Nrf2 signaling pathway, and inhibiting key molecules in the NF-κB and NLRP3 signaling pathways. This study provides new insights into the underlying molecular mechanisms of CGA's protective effects, highlighting its potential as a natural antioxidant for bovine mammary health and contributing to the broader application of polyphenolic compounds in managing oxidative stress and inflammation.

Photodamage, a type of skin inflammation caused by excessive exposure to solar radiation, leads to skin redness, inflammation, and even the development of skin cancer, posing a severe threat to individuals living at high altitudes. UVB radiation is considered the primary factor contributing to photodamage. It stimulates macrophages within the epidermis, triggers inflammasome activation, and increases the inflammatory cytokine interleukin-1β (IL-1β) production. This study examined the protective effects of the compound isolicoflavonol (ILF) and its mechanism against UVB-induced photodamage. We irradiated UVB to create a photodamage model in mice and macrophages. Next, we assessed ILF's ability to protect the skin and cells from UVB photodamage and its inhibitory effects on UVB-mediated NLRP3 inflammasome. Our findings indicated that ILF reduced UVB-induced skin injury and inflammation in mouse skin, decreased cell death, NLRP3 inflammasome activation, ROS production, and mitochondrial dysfunction. These results suggest that ILF may be a potent agent for protecting the skin against UVB-induced photodamage.

The spleen, as the body's largest peripheral immune organ and a crucial source of circulating monocytes, plays a significant role in the acute inflammatory response of spleen-derived macrophages to diseases. Therefore, studying the impact and mechanism of X-ray irradiation on spleen-derived macrophages' inflammatory responses is of great importance.

Extracted and identified mice splenic macrophages were divided into four groups: control group, LPS and ATP co-stimulated non-irradiated group, LPS and ATP co-stimulated group irradiated after 6 h, and LPS and ATP co-stimulated group irradiated after 12 h In the LPS and ATP co-stimulated groups, LPS (1μg/ml) and ATP (5mmol/L) were added to establish an inflammatory model in mice splenic macrophages. The irradiated groups were exposed to a medical linear accelerator (Elekta Synergy), while the non-irradiated groups were placed under the light source for the same duration without irradiation. Protein extraction was performed in each group at 6 h and 12 h post-treatment for subsequent analysis using Western blot, ELISA, RT-qPCR and other relevant methods.

(1) Compared with the non-irradiated group, the cell activity in the groups irradiated for 6 h and 12 h at 8 Gy showed a significant increase (P<0.01). (2) In the LPS and ATP co-stimulated groups irradiated after 6 h and 12 h, the expression of NLRP3 mRNA and protein, IL-18 and IL-1β showed a notable decrease compared to the LPS and ATP co-stimulated non-irradiated group (P<0.05). Additionally, caspase-1 expression of caspase-1 mRNA and protein in the 12 h post-irradiation group also decreased considerably when compared with the LPS and ATP co-stimulated non-irradiated group (P < 0.05). In the groups irradiated after 6 h and 12 h, (3) there was a remarkable decrease in the expression of TWIK mRNA and TWIK2, (4) as well as Gq mRNA and protein, when compared to the LPS and ATP co-stimulated non-irradiated group (P < 0.05). Particularly, the 12 h post-irradiation group exhibited a notable reduction in PKC expression (P < 0.05).

X-ray irradiation is capable of inhibiting the activation of ATP-dependent NLRP3 inflammasomes in splenic macrophages.

Pyroptosis, a novel mode of inflammatory cell death, is executed by membrane pore-forming gasdermin (GSDM) family members in response to extracellular or intracellular injury cues and is characterized by a ballooning cell morphology, plasma membrane rupture and the release of inflammatory mediators such as interleukin-1β (IL-1β), IL-18 and high mobility group protein B1 (HMGB1). It is a key effector mechanism for host immune defence and surveillance against invading pathogens and aberrant cancerous cells, and contributes to the onset and pathogenesis of inflammatory and autoimmune diseases. Manipulating the pore-forming activity of GSDMs and pyroptosis could lead to novel therapeutic strategies. In this Review, we discuss the current knowledge regarding how GSDM-mediated pyroptosis is initiated, executed and regulated, its roles in physiological and pathological processes, and the crosstalk between different modes of programmed cell death. We also highlight the development of drugs that target pyroptotic pathways for disease treatment.

NLRP3 inflammasome is critical in innate immunity and inflammatory responses. A series of novel sulfonylurea-based NLRP3 inflammasome inhibitors was designed and synthesized. Notably, compound 15 exhibited the potent NLRP3 inhibitory activity, effectively suppressing IL-1β secretion in THP-1 (IC50 = 23 nM), demonstrating better efficacy compared to MCC950. It selectively inhibits NLRP3 activation by disrupting inflammasome assembly, with no effect on NLRC4 or AIM2 inflammasomes. Molecular docking showed that the 1-methyl-4-(methylamino)piperidine moiety forms a novel hydrogen bond with Asp662 in the hydrophilic region of NLRP3. Additionally, compound 15 displayed excellent pharmacokinetic properties with 99.6% oral bioavailability in mice. It exhibited superior efficacy in acute peritonitis and diabetic kidney disease models, surpassing MCC950. Tissue distribution studies confirmed that compound 15 specifically targeted the gut and showed efficacy in an IBD model, comparable to MCC950. These findings highlight compound 15 as a promising lead for novel oral NLRP3 inflammasome inhibitors.

Ubiquitin ligases play pivotal roles in the regulation of NLR family pyrin domain containing 3 (NLRP3) inflammasome activation, a critical process in innate immunity and inflammatory responses. This review explores the intricate mechanisms by which various E3 ubiquitin ligases exert both positive and negative influences on NLRP3 inflammasome activity through diverse post-translational modifications. Negative regulation of NLRP3 inflammasome assembly is mediated by several E3 ligases, including F-box and leucine-rich repeat protein 2 (FBXL2), tripartite motif-containing protein 31 (TRIM31), and Casitas B-lineage lymphoma b (Cbl-b), which induce K48-linked ubiquitination of NLRP3, targeting it for proteasomal degradation. Membrane-associated RING-CH 7 (MARCH7) similarly promotes K48-linked ubiquitination leading to autophagic degradation, while RING finger protein (RNF125) induces K63-linked ubiquitination to modulate NLRP3 function. Ariadne homolog 2 (ARIH2) targets the nucleotide-binding domain (NBD) domain of NLRP3, inhibiting its activation, and tripartite motif-containing protein (TRIM65) employs dual K48 and K63-linked ubiquitination to suppress inflammasome assembly. Conversely, Pellino2 exemplifies a positive regulator, promoting NLRP3 inflammasome activation through K63-linked ubiquitination. Additionally, ubiquitin ligases influence other components critical for inflammasome function. TNF receptor-associated factor 3 (TRAF3) mediates K63 polyubiquitination of apoptosis-associated speck-like protein containing a CARD (ASC), facilitating its degradation, while E3 ligases regulate caspase-1 activation and DEAH-box helicase 33 (DHX33)-NLRP3 complex formation through specific ubiquitination events. Beyond direct inflammasome regulation, ubiquitin ligases impact broader innate immune signaling pathways, modulating pattern-recognition receptor responses and dendritic cell maturation. Furthermore, they intricately control NOD1/NOD2 signaling through K63-linked polyubiquitination of receptor-interacting protein 2 (RIP2), crucial for nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) activation. Furthermore, we explore how various pathogens, including bacteria, viruses, and parasites, have evolved sophisticated strategies to hijack the host ubiquitination machinery, manipulating NLRP3 inflammasome activation to evade immune responses. This comprehensive analysis provides insights into the molecular mechanisms underlying inflammasome regulation and their implications for inflammatory diseases, offering potential avenues for therapeutic interventions targeting the NLRP3 inflammasome. In conclusion, ubiquitin ligases emerge as key regulators of NLRP3 inflammasome activation, exhibiting a complex array of functions that finely tune immune responses. Understanding these regulatory mechanisms not only sheds light on fundamental aspects of inflammation but also offers potential therapeutic avenues for inflammatory disorders and infectious diseases.

Cholestatic liver disease, characterized by impaired bile flow, leads to the accumulation of harmful metabolites and toxins, resulting in liver damage. Inflammatory cytokines are crucial for the progression of this condition. Clusterin is a glycoprotein with roles in cell death, lipid transport, and cellular protection. We previously demonstrated that clusterin protects against hepatic steatosis and hepatic fibrosis. This study explored the roles of clusterin in cholestatic liver injury induced by a DDC (3,5-diethoxycarbonyl-1,4-dihydrocollidine) diet.

The study evaluated the impact of clusterin on liver injury in C57BL/6 mice and clusterin-knockout (KO) mice fed a DDC diet for 10-20 days. Primary Kupffer cells (KCs) and hepatocytes (HCs) of these mice were analyzed. Techniques such as Sirius red staining, immunohistochemistry, real-time RT-PCR, enzyme-linked immunosorbent assays, and western blotting were performed to assess the effects of clusterin.

Clusterin expression was upregulated in the cholestatic liver. Clusterin-KO mice exhibited elevated levels of alanine aminotransferase, aspartate aminotransferase, collagen, and αSMA upon DDC diet-induced liver injury. They also had increased levels of markers of endoplasmic reticulum (ER) stress (CHOP, ATF6, and p-eIF2α) and inflammasome activity (NLRP3, ASC, caspase-1, and interleukin 1 beta (IL1β) protein expression, and IL1β and interleukin 18 secretion). Thapsigargin, an ER stress inducer, heightened NLRP3 inflammasome activation in primary KCs and HCs, which was mitigated by overexpression of clusterin.

The absence of clusterin exacerbates ER stress and NLRP3 inflammasome activation in mice fed a DDC diet. Conversely, overexpression of clusterin suppresses these stress responses. Thus, clusterin deficiency is associated with an enhanced inflammasome response in the liver that is linked to upregulation of ER stress.

Ambient particulate matter (PM) exposure is a known risk factor for cardiovascular diseases. Epidemiological studies have shown the association between PM exposure and vascular complications, including vasculitis, embolism, hypertension, stroke, and atherosclerosis. However, the exact mechanisms underlying its vascular toxicity, especially in relation to short-term exposures, remain incompletely understood. This study investigates the role of PM and its carbonaceous cores in driving vascular endothelial inflammation via inflammasome activation. We hypothesized that PM SRM1648a exposure induces vascular endothelial inflammation through oxidative stress and inflammasome activation. Short-term exposure to PM SRM1648a was assessed in BALB/c mice for systemic inflammation and oxidative stress biomarkers, alongside in vitro studies in HUVECs and EA.hy926 endothelial cells to elucidate inflammasome activation pathways. PM SRM1648a exposure significantly altered redox balance and cytokine profiles in mice and upregulated NLRP3/NLRC4 inflammasomes in vascular endothelial cells, leading to caspase-1/IL-1β activation. Intriguingly, pyroptosis was not the primary mode of cell death. In vitro studies demonstrated that antioxidants glutathione monoethyl ester effectively mitigated oxidative stress and inflammasome activation in endothelial cells. This study highlights the critical role of ROS-mediated inflammasome activation in vascular inflammation induced by PM SRM1648a, with carbon-based cores as key contributors.

The discovery of DFV890 ((R)-1), a potent and selective NLRP3 antagonist, is described. Replacement of the sulfonyl urea core from the first-generation NLRP3 antagonist CRID3 with a sulfonimidamide core afforded a novel and potent series of NLRP3 antagonists. The (R)-enantiomers of the sulfonimidamide series were found to be consistently more potent than structurally related sulfonyl ureas. Replacement of the furan unit of CRID3 with a 5-substituted thiazole unit led to DFV890 ((R)-1), which potently inhibited IL-1β production in THP-1 cells and in primary human cells, blocked multiple downstream effectors of NLRP3 activation, and substantially improved PK properties and significantly lowered the predicted human dose compared to that for CRID3. DFV890 ((R)-1) was also effective in an air pouch model of gout.

Porphyromonas gingivalis (Pg) is a prevalent pathogen that promotes human periodontal disease (PD) and exacerbates systemic comorbidities such as atherosclerosis, rheumatoid arthritis, and Alzheimer's disease. Pg produces nonphosphorylated tetra-acylated lipid A (NPLA) in its outer membrane (OM) that evades host Toll-like receptor 4 (TLR4), inflammasome pathways, and cationic peptides, enhancing bacterial survival. Here, we show that Pg also releases outer membrane vesicles (OMVs) that engage and divert host cell TLR4, inflammasome, and LL-37 responses away from the microbe. We determined that Pg OMVs are enriched for C4' monophosphoryl lipid A (C4'-MPLA), an established agonist for TLR4-TRIF-IFNβ and inflammasome-IL-1β responses. Comparisons of Pg 381 and Pg 33277 stationary phase cultures revealed higher OMV production by Pg 381, which correlates with its higher proinflammatory pathogenicity. The cationic peptide, polymyxin B (PMB), which selectively binds lipid A C4'-phosphate, reduces OMV-stimulated HEK cell TLR4 activation and THP-1 cell IL-1β production, confirming the proinflammatory role for OMV-C4'-MPLA. Similar to PMB, the host defense peptide, LL-37, inhibits OMV-C4'-MPLA-dependent HEK cell TLR4 activation. PMB and LL-37 also blocked OMV-C4'-MPLA-driven TLR4 activation in human umbilical vein endothelial cells. Finally, wild-type Pg-containing OM-NPLA is highly resistant to LL-37 antimicrobial activity, whereas the ΔlpxF mutant bacterium, retaining OM-C4'-MPLA, is killed by the peptide. In summary, Pg escapes host TLR4 signaling, inflammasome activation, and LL-37 interaction by retaining immunoevasive OM-NPLA. Moreover, Pg dispenses proinflammatory OMV-C4'-MPLA, which engages and redirects those host defenses. We suggest that OMV-C4'-MPLA triggers elevated IFNβ and IL-1β cytokines, which typify PD comorbidities, and drive PD-related alveolar bone loss.

Although platelets play a critical pathogenic role in myocardial infarction (MI), few studies have characterized the MI platelet transcriptome in the acute or chronic setting in women. We report that transcripts associated with the actin cytoskeleton, Rho family GTPases, mitochondrial dysfunction, and inflammatory signaling are enriched in platelets from MI patients in the acute setting (n = 40, MI; n = 38, control) and do not significantly change over time. Furthermore, 79 platelet genes chronically elevated or suppressed after MI are associated with future cardiovascular events in an independent high-risk cohort (n = 135). Compared with women with MI with nonobstructive coronary arteries, platelets from women with MI and obstructive coronary artery disease were enriched in neutrophil activation and proinflammatory signaling pathways driven by increased tumor necrosis factor (TNF)-α signaling. Hierarchic clustering of the MI transcriptomic profile identified 3 subgroups with distinctive biological pathways and MI correlates. Our data demonstrate that platelets from MI patients are phenotypically different from MI-naïve patients in the acute and chronic settings and reveal a platelet transcriptomic signature with distinct clinical features.

The NLRP3 inflammasome is a multiprotein complex that mediates caspase-1 activation and the release of proinflammatory cytokines, including interleukin (IL)-1β and IL-18. Gain-of-function variants in the gene encoding NLRP3 (also called cryopyrin) lead to constitutive inflammasome activation and excessive IL-1β production in cryopyrin-associated periodic syndromes (CAPS). Here we present functional screening and automated analysis of 534 NLRP3 variants from the international INFEVERS registry and the ClinVar database. This resource captures the effect of NLRP3 variants on ASC speck formation spontaneously, at low temperature, after inflammasome stimulation and with the specific NLRP3 inhibitor MCC950. Most notably, our analysis facilitated the updated classification of NLRP3 variants in INFEVERS. Structural analysis suggested multiple mechanisms by which CAPS variants activate NLRP3, including enhanced ATP binding, stabilizing the active NLRP3 conformation, destabilizing the inactive NLRP3 complex and promoting oligomerization of the pyrin domain. Furthermore, we identified pathogenic variants that can hypersensitize the activation of NLRP3 in response to nigericin and cold temperature exposure. We also found that most CAPS-related NLRP3 variants can be inhibited by MCC950; however, NLRP3 variants with changes to proline affecting helices near the inhibitor binding site are resistant to MCC950, as are variants in the pyrin domain, which likely trigger activation directly with the pyrin domain of ASC. Our findings could help stratify the CAPS population for NLRP3 inhibitor clinical trials and our automated methodologies can be implemented for molecules with a different mechanism of activation and in laboratories worldwide that are interested in adding new functionally validated NLRP3 variants to the resource. Overall, our study provides improved diagnosis for patients with CAPS, mechanistic insight into the activation of NLRP3 and stratification of patients for the future application of targeted therapeutics.

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-1β 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.

Inflammasomes are protein complexes that trigger pro-inflammatory responses and promote many diseases, including adipose tissue dysfunction. Linagliptin (L), a DPP-4 inhibitor used for type 2 diabetes therapy, has putative anti-inflammatory effects. This work explores L effects on inflammasome regulation, inflammation, and adipose tissue dysfunction in obese mice. Male C57BL/6N mice were fed a normal chow (NC) diet, high-fat (HF) diet, or HF diet with L (HFL) for 15 weeks. Gene expression and histological examinations were performed on visceral (VAT) and subcutaneous (SAT) adipose tissue samples. Biomarkers were quantified on sera. Murine macrophages were utilized for in vitro analyses. L decreased HF-induced endotoxemia and circulating inflammatory indicators. Despite having no effect on body weight, L reduced VAT inflammation by decreasing endotoxemia-induced NLRC4 inflammasome, inflammation severity, and fat cell hypertrophy. Although SAT response differed from VAT, inflammation was slightly reduced in this tissue too. In vitro, L modulated inflammation by directly reducing the pro-inflammatory macrophage phenotype. In obesity, increased NLRC4 inflammasome expression links endotoxemia and VAT inflammation. L protected against endotoxemia, maybe by affecting gut permeability and VAT responses. The decreased polarization of macrophages toward a pro-inflammatory phenotype and the reduction in adipocyte hypertrophy are involved in the response to L.

The link between cardiovascular disease (CVD) and metabolic dysfunction-associated steatotic liver disease (MASLD) is well-established at both the epidemiological and pathophysiological levels. Among the common pathophysiological mechanisms involved in the development and progression of both diseases, oxidative stress and inflammation, insulin resistance, lipid metabolism deterioration, hepatokines, and gut dysbiosis along with genetic factors have been recognized to play a pivotal role. Pharmacologic interventions with drugs targeting common modifiable cardiometabolic risk factors, such as T2DM, dyslipidemia, and hypertension, are a reasonable strategy to prevent CVD development and progression of MASLD. Recently, a novel drug for metabolic dysfunction-associated steatohepatitis (MASH), resmetirom, has shown positive effects regarding CVD risk, opening new opportunities for the therapeutic approach of MASLD and CVD. This review provides current knowledge on the epidemiologic association of MASLD to CVD morbidity and mortality and enlightens the possible underlying pathophysiologic mechanisms linking MASLD with CVD. The role of cardiometabolic drugs such as anti-hypertensive drugs, hypolipidemic agents, glucose-lowering medications, acetylsalicylic acid, and the thyroid hormone receptor-beta agonist in the progression of MASLD is also discussed. Metformin failed to prove beneficial effects in MASLD progression. Studies on the administration of thiazolinediones in MASLD suggest effectiveness in improving steatosis, steatohepatitis, and fibrosis, while newer categories of glucose-lowering agents such as GLP-1Ra and SGLT-2i are currently being tested for their efficacy across the whole spectrum of MASLD. Statins alone or in combination with ezetimibe have yielded promising results. The conduction of long-duration, large, high-quality, randomized-controlled trials aiming to assess by biopsy the efficacy of cardiometabolic drugs to reverse MASLD progression is of great importance.

Accumulating studies have unraveled that dexmedetomidine (DEX) is neuroprotective against brain damage. However, it remains largely unknown about the mechanism involved in the neuroprotective effect of DEX. Therefore, this study explored whether DEX could affect mitophagy and pyroptosis in hypoxic-ischemic brain damage. We established a hippocampal neuron model of oxygen glucose-deprivation (OGD) and a rat model of cerebral ischemia/reperfusion (I/R) injury, which were then intervened with DEX and the autophagy inhibitor (3-MA). It was found that DEX intervention significantly increased neuron viability and mitophagy. Additionally, DEX intervention reversed increased oxidative stress and pyroptosis caused by OGD. DEX intervention further maintained the activation of the PINK1/Parkin pathway, while 3-MA treatment partly counteracted the protective effect of DEX on OGD-induced hippocampal neurons, suggesting that the inhibition of the PINK1/Parkin pathway reversed the function of DEX to increase cell viability and mitophagy and inhibit oxidative stress, pyroptosis, and apoptosis. Animal experiments also revealed that DEX intervention induced PINK1/Parkin pathway activation, reduced cerebral infarction and mitochondrial damage, promoted mitophagy, and inhibited pyroptosis, which was nullified by 3-MA treatment. Conclusively, DEX protects against pyroptosis and activates mitophagy in OGD/R-induced brain damage by activating the PINK1/Parkin pathway.

NLRP3 (NOD, LRR and pyrin domain-containing protein 3) inflammasome is important for host defense against infections and maintaining homeostasis. Aberrant activation of NLRP3 inflammasome is closely related to various inflammatory diseases. Post-translational modifications are critical for NLRP3 inflammasome regulation. However, the mechanism of NLRP3 inflammasome activation remains incompletely understood. Here, it is demonstrated that the Ufm1 E3 ligase Ufl1 mediated UFMylation is essential for NLRP3 inflammasome activation. Mechanistically, Ufl1 binds and UFMylates NLRP3 in the priming stage of NLRP3 activation, thereby sustaining the stability of NLRP3 by preventing NLRP3 K63-linked ubiquitination and the subsequent autophagic degradation. It is further demonstrated that myeloid cell-specific Ufl1 or Ufm1 deficiency in mice significantly alleviated inflammatory responses and tissue damage following lipopolysaccharide (LPS)-induced endotoxemia and alum-induced peritonitis. Thus, the findings offer new insights into potential therapeutic targets for NLRP3 inflammasome-related diseases by targeting the UFMylation system.

The rising rates of gallstones and cholecystectomy in pediatric populations underscore the increasing concern regarding chronic cholecystitis. However, the morphopathogenesis of pediatric calculous cholecystitis is still not well understood. This study aimed to determine the expression and distribution of immunomodulatory factors interleukin-12 (IL-12), interleukin-13 (IL-13), interleukin-1β (IL-1β), sonic hedgehog protein (SHH), nuclear factor NF-kappa-B p65 subunit (NFkBp65), and heat shock protein 60 (HSP60) in the gallbladder walls of pediatric patients with chronic calculous cholecystitis.

In total, 11 gallbladder samples were collected from pediatric patients with calculous cholecystitis during cholecystectomy, while 5 healthy gallbladder samples served as controls. IL-12, IL-13, IL-1β, SHH, NFkBp65, and HSP60 were detected by immunohistochemistry. The number of positive structures in gallbladder wall epithelium, vasculature, and inflammatory infiltrate was assessed semi-quantitatively by microscopy. A Mann-Whitney U test and Spearman's rank-order correlation coefficient were calculated.

Statistically significant differences were observed between patient and control samples in the expression of IL-1β, SHH, and NFkBp65 in the epithelium, as well as in the expression of IL-12, SHH, and HSP60 in the blood vessels. The expression of IL-1β was stronger in the epithelium of controls, while other markers were more prominent in patient samples.

An increased number of NFkBp65, IL-12, and HSP60 positive cells in patient gallbladder tissue suggests a significant role of these tissue factors in driving immune modulation and sustaining the inflammation in pediatric chronic calculous cholecystitis. The noticeable expression of SHH in patient gallbladder tissue indicates its part in tissue regeneration and repair processes, as well as in modulating inflammation and vascular responses in calculous cholecystitis. The significant positive correlations between the factors studied highlight the importance of their coordinated interaction and intricate crosstalk in the morphopathogenesis of calculous cholecystitis.

The complement system plays a crucial role in various pathophysiological conditions, including snake envenomation. In this study, we investigated the effects of Bitis arietans venom on the complement system using an ex vivo human whole blood model. Our findings demonstrate that B. arietans venom was able to activate the complement system, leading to a significant increase in the production of anaphylatoxins (C3a/C3a-desArg, C5a/C5a-desArg) and the soluble Terminal Complement Complex (sTCC). Inhibition of the C3 component by Cp40, a C3-C3b inhibitor, resulted in the reduction of C3a/C3a-desArg, C5a/C5a-desArg, and sTCC levels to baseline in venom-stimulated samples. Furthermore, treatment with Cp40 promoted a substantial decrease in the production of pro-inflammatory mediators, such as Prostaglandin E2 (PGE2), IL-8/CXCL8, MCP-1/CCL2, and MIG/CXCL9. To further elucidate the molecular mechanisms, we utilized the THP-1 cell line differentiated into M0 macrophages. Incubation of these macrophages with human plasma, from the human whole blood treated with B. arietans venom, resulted in the expression of the NLRP3 inflammasome and the production of IL-8 and IL-1β. Importantly, Cp40 was able to diminish the production of these cytokines, as well as the levels of ASC and caspase-1 proteins. In conclusion, our results indicate that the inhibition of the complement by Cp40 at C3/C3b level can modulate the inflammatory response and inflammasome activation induced by B. arietans venom. These findings suggest that complement inhibition may be a promising therapeutic approach for managing the inflammatory complications associated with this snake envenomation.

Aberrant activation of NLRP3 inflammasome is involved in various inflammatory diseases, making it a promising target for therapeutic intervention. NEK7, a member of the NIMA-related kinase (NEK) family, functions as a key NLRP3-binding protein and plays a crucial role in the regulation of NLRP3 inflammasome assembly and activation. Thus, disrupting NLRP3-NEK7 interactions by targeting NEK7 could be a promising strategy to inhibit the activation of NLRP3 inflammasome. In this work, a series of novel urea derivatives were designed and synthesized based on the reported NEK7 inhibitors. Among these, compound 23 exhibited potent activity against IL-1β release with low cytotoxicity. Moreover, compound 23 enhanced the thermal stability of NEK7 and disrupted the NLRP3-NEK7 interaction, thereby regulating NLRP3 inflammasome assembly.

Spinal cord injury (SCI) is a serious and disabling central nervous system injury that can trigger various neuropathological conditions, resulting in neuronal damage and release of various pro-inflammatory mediators, leading to neurological dysfunction. Currently, surgical decompression, drugs and rehabilitation are primarily used to relieve symptoms and improve endogenous repair mechanisms; however, they cannot directly promote nerve regeneration and functional recovery. SCI can be divided into primary and secondary injuries. Secondary injury is key to determining the severity of injury, whereas inflammation and cell death are important pathological mechanisms in the process of secondary SCI. The activation of the inflammasome complex is thought to be a necessary step in neuro-inflammation and a key trigger for neuronal death. The NLRP3 inflammasome is a cytoplasmic multiprotein complex that is considered an important factor in the development of SCI. Once the NLRP3 inflammasome is activated after SCI, NLRP3 nucleates the assembly of an inflammasome, leading to caspase 1-mediated proteolytic activation of the interleukin-1β (IL-1β) family of cytokines, and induces an inflammatory, pyroptotic cell death. Inhibition of inflammasomes can effectively inhibit inflammation and cell death in the body and promote the recovery of nerve function after SCI. Therefore, inhibition of NLRP3 inflammasome activation may be a promising approach for the treatment of SCI. In this review, we describe the current understanding of NLRP3 inflammasome activation in SCI pathogenesis and its subsequent impact on SCI and summarize drugs and other potential inhibitors based on NLRP3 inflammasome regulation. The objective of this study was to emphasize the role of the NLRP3 inflammasome in SCI, and provide a new therapeutic strategy and theoretical basis for targeting the NLRP3 inflammasome as a therapy for SCI.

Traumatic brain injury (TBI) has a complex and multifactorial pathology and is a major cause of death and disability for humans. Immediately after TBI, astrocytes and microglia react with complex morphological and functional changes known as reactive gliosis to form a glial scar in the area immediately adjacent to the lesion, which is the major barrier to neuronal regeneration. The flavonoid agathisflavone (bis-apigenin), present in Poincianella pyramidalis leaves, has been shown to have neuroprotective, neurogenic, and anti-inflammatory effects, demonstrated in vitro models of glutamate-induced toxicity, neuroinflammation, and demyelination. In this study, we evaluated the effect and mechanisms of agathisflavone in neuronal integrity and in the modulation of gliosis in an ex vivo model of TBI. For this, microdissections from the encephalon of Wistar rats (P6-8) were prepared and subjected to mechanical injury (MI) and treated or not with daily agathisflavone (5 μM) for 3 days. Astrocyte reactivity was investigated by measuring mRNA and expression of GFAP protein in the lesioned area by immunofluorescence and Western blot. The proportion of microglia was determined by immunofluorescence for Iba-1; mRNA expression for inflammasome NRPL3 and interleukin-1 beta (IL-1β) was determined by RT-qPCR. It was observed that lesions in the cortical tissue induced astrocytes overexpressing GFAP in the typical glial scar formed and that agathisflavone modulated GFAP expression at the transcriptional and post-transcriptional levels, which was associated with a reduction of the glial scar. MI induced an increase in the proportion of microglia (Iba-1+), which was not observed in agathisflavone-treated cultures. Moreover, the flavonoid modulated negatively both the NRLP3 and IL-1β mRNA expression that was increased in the lesioned area of the tissue. These findings support the regulatory properties of agathisflavone in the control of the inflammatory response in glial cells, which can impact neuroprotection and should be considered for future studies for TB and other pathological conditions of the central nervous system.

The complex pathophysiology of Alzheimer's disease (AD) poses challenges for the development of therapies. Recently, neuroinflammation has been identified as a key pathogenic mechanism underlying AD, while inflammation has emerged as a possible target for the management and prevention of AD. Several prior studies have demonstrated that medications modulating neuroinflammation might lessen AD symptoms, mostly by controlling neuroinflammatory signaling pathways such as the NF-κB, MAPK, NLRP3, etc, and their respective signaling cascade. Moreover, targeting these inflammatory modalities with inhibitors, natural products, and metabolites has been the subject of intensive research because of their anti-inflammatory characteristics, with many studies demonstrating noteworthy pharmacological capabilities and potential clinical applications. Therefore, targeting inflammation is considered a promising strategy for treating AD. This review comprehensively elucidates the neuroinflammatory mechanisms underlying AD progression and the beneficial effects of inhibitors, natural products, and metabolites in AD treatment.

Laboratory-based immunology evaluation is essential to the diagnostic workup of patients with complex immune disorders, and is as essential, if not more so, depending on the context, as genetic testing, because it enables identification of aberrant pathways amenable to therapeutic intervention and clarifies variants of uncertain significance. There have been considerable advances in techniques and instrumentation in the clinical laboratory in the past 2 decades, although there are still "miles to go." One of the goals of the clinical laboratory is to ensure advanced diagnostic testing is widely accessible to physicians and thus patients, through reference laboratories, particularly in the context of academic medical centers. This ensures a greater likelihood of translating research discoveries into the diagnostic laboratory, on the basis of patient care needs rather than a sole emphasis on commercial utility. However, these advances are under threat from burdensome regulatory oversight that can compromise, at best, and curtail, at worst, the ability to rapidly diagnose rare immune disorders and ensure delivery of precision medicine. This review discusses the clinical utility of diagnostic immunology tools, beyond cellular immunophenotyping of lymphocyte subsets, which can be used in conjunction with clinical and other laboratory data for diagnosis as well as monitoring of therapeutic response in patients with genetic immunologic diseases.

Ginsenoside Rd (Rd) is a bioactive compound predominantly found in Panax ginseng C.A. Meyer and Panax notoginseng (Burkill) F.H. Chen ex C.H. Chow, both species belonging to genus Panax in the Araliaceae family. However, its hepatic protective effect against acute liver injury and related mechanistic action remain unexplored. To investigate the protective effect of Rd against thioacetamide (TAA)-induced acute liver injury and assess its underlying regulatory mechanisms related to autophagy and inflammation. Forty-eight 8 weeks old C57BL/6 mice were treated with saline (control or model group), Rd (12.5 mg/kg, 25 mg/kg or 50 mg/kg), and diammonium glycyrrhizinate (DG, 30 mg/kg) for three days. Then the mice were stimulated with TAA to establish acute liver injury model, excluding the control group. HSC-T6 cells were treated with Rd at concentrations of 2.5, 5, or 10 µM, for 12 h with or without Lipopolysaccharide (LPS) stimulation at 100 ng/mL. Immunofluorescence staining, qPCR and Western blot were employed to analyze the expressions of genes and proteins associated with inflammation and autophagy. To validate the role of Rd in regulating autophagy and inflammation, the autophagy inducers, rapamycin and GSK621, were utilised in reverse validation experiments in cells. Rd exhibited significant hepatic protective effects in mice by reducing the serum levels of Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Glutathione S-transferase (GST) and Lactate dehydrogenase (LDH) with acute liver injury. It exhibited strong anti-inflammatory effect by reducing inflammation associated protein, such as cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), nod-like receptor protein 3 (NLRP3), associated speck-like protein containing a CARD (ASC), interleukin-18 (IL-18) and interleukin-1β(IL-1β) proteins and the mRNA expression levels of COX-2, Tumor Necrosis Factor α (TNF α), interleukin-6 (IL-6) and iNOS were decreased in liver tissue. And Rd inhibited LPS-induced inflammation by reducing the expression of COX-2 and NLRP3 in HSC-T6 cells. Moreover, not only in vivo but also in vitro, Rd downregulated the expression of LC3II, Beclin1, phosphorylation-AMP-activated protein kinase (p-AMPK), phosphorylation-ULK1 (p-ULK1) and upregulated the expression of p62 and phosphorylation-mechanistic target of rapamycin (p-mTOR) to suppress autophagy via the AMPK/mTOR/ULK1 pathway. Finally, the inhibitory effects of Rd on autophagy and inflammation in HSC-T6 cells were partially blocked by rapamycin and GSK621. Rd is a promising therapeutic agent to protect liver against TAA-induced acute liver injury by regulating the autophagy-NLRP3 inflammasome pathway.

Atherosclerosis serves as the fundamental pathology for a variety of cardiovascular disorders, with its pathogenesis being closely tied to the complex interplay among lipid metabolism, oxidative stress, and inflammation. Wogonoside is a natural flavonoid extracted from Scutellaria baicalensis with a variety of biological activities, including anti-inflammatory, hypolipidemic, and cardiac function improvement properties. Despite these known effects, the specific role of wogonoside in the context of atherosclerosis remains to be elucidated.

To validate the efficacy of wogonoside in the treatment of atherosclerosis and to investigate its possible therapeutic mechanisms.

Network pharmacology was used to obtain the core targets and signaling pathways that may be efficacious in the treatment of atherosclerosis with wogonoside, which were validated using molecular docking and molecular dynamics simulations. To further validate the core targets in the signaling pathway, we performed in vivo experiments using apolipoprotein E (ApoE)-/- mice. This included pathological morphology and lipid deposition analysis of mouse aorta, serum lipid level analysis, Elisa analysis, oxidative stress analysis, reactive oxygen species (ROS) fluorescence assay, immunohistochemical analysis and protein blot analysis.

Predictions were obtained that wogonoside treatment of atherosclerosis has 31 core targets, which are mainly focused on pathways such as Toll-like receptor (TLR) signaling pathway and NF-kappa B (NF-κB ) signaling pathway. Molecular docking and molecular dynamics simulations showed that wogonoside has good binding properties to the core targets. In vivo experimental results showed that wogonoside significantly inhibited aortic inflammatory response and lipid deposition, significantly reduced the release levels of total cholesterol (TC), triglycerides (TG), low-density-lipoprotein cholesterol (LDL-C), oxidized low density (ox-LDL) and free fatty acid (FFA), and significantly inhibited the release of inflammatory factors TNF-α, IL-1β, IL-6 and oxidative stress in ApoE-/- mice. Further molecular mechanism studies showed that wogonoside significantly inhibited the activation of TLR4/NF-κB signaling pathway in ApoE-/- mice.

Wogonoside may be an effective drug monomer for the treatment of atherosclerosis, and its mechanism of action is closely related to the inhibition of the activation of the TLR4/NF-κB signaling pathway.

Purpose: This study is aimed at investigating the role of key molecular elements involved in pyroptosis in liver injury caused by exertional heat stroke (EHS). Methods: We established a model of EHS-induced liver injury in Sprague-Dawley rats, with a control group (receiving no treatment) for comparison and 12 rats in each group. Alanine transaminase (ALT) and aspartate transaminase (AST) levels in the blood were detected. Interleukin-1 beta (IL-1β) and interleukin-18 (IL-18) levels were assessed using enzyme-linked immunosorbent assays (ELISA). Pathological changes in liver tissue were examined by hematoxylin and eosin (H&E) staining. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to detect mRNA and protein expression levels of Caspase-1 and Gasdermin D. Results: Compared to the control group, the liver tissue of the EHS group showed congestion in hepatic sinusoids, hepatocyte edema, eosinophilic changes, necrosis, and infiltration of inflammatory cells. ALT and AST levels in the EHS group were significantly higher than those in the control group (p < 0.05). The mRNA expressions of Caspase-1, Gasdermin D, IL-1β, and IL-18 were significantly increased in the EHS group compared to the control group (p < 0.001). The protein expressions of Caspase-1, cleaved Caspase-1, Gasdermin D, and cleaved Gasdermin D were significantly increased in the EHS group. Conclusion: These findings indicated that hepatic pyroptosis plays an important role in EHS-induced liver injury.

Atopic dermatitis (AD) is a prevalent inflammatory skin disorder characterized by its chronic, persistent, and recurrent nature. The pathophysiology of this condition is complex, involving various factors including cell-mediated immune responses, compromised skin barrier function, and alterations in hypersensitivity reactions. These components synergistically contribute to the perpetuation of the bothersome "itch-scratch-itch" cycle. Recent research has highlighted the significant role of the NLRP3 inflammasome in the development of AD and other inflammatory conditions. Current research indicates that the NLRP3 inflammasome plays a pivotal role in both the acute and chronic phases of AD by modulating the Th2/Th1 immune deviation. Moreover, the pharmacological suppression of NLRP3 has shown promising results in mitigating the pathological aspects of AD. This review outlines potential drug development strategies that target the NLRP3 inflammasome as a therapeutic approach for AD and the challenges faced in this endeavor.

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of many malignant tumors. However, ICI-induced hyper-immune activation causes cardiotoxicity. Traditional treatments such as glucocorticoids and immunosuppressants have limited effectiveness and may even accelerate tumor growth. This study aimed to identify approaches that effectively reduce cardiotoxicity and simultaneously preserve or enhance the antitumor immunity of ICI therapy.

ICI injection in melanoma-bearing C57BL/6J female mice was used to simulate cardiotoxicity in patients with tumor undergoing immune therapy. MCC950 was used to block nod-like receptor protein 3 (NLRP3) inflammasome activity. Echocardiography, immunofluorescence, flow cytometry, and reverse transcription quantitative polymerase chain reaction were used to assess cardiac function, immune cell populations, and inflammatory factor levels. Bulk and single-cell RNA sequencing was used to detect the changes in cardiac transcriptome and immunological network.

NLRP3 inhibition reduced inflammatory response and improved cardiac function. Notably, NLRP3 inhibition also resulted in a pronounced suppression of tumor growth. Single-cell RNA sequencing elucidated that MCC950 treatment reduced the cardiac infiltration of pathogenic macrophages, cytotoxic T cells, activated T cells, and their production of inflammatory cytokines, while enhancing the presence of reparative macrophages and naive T cells. In addition, MCC950 attenuated cardiotoxicity induced by dual programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) immunotherapy and promoted tumor regression, and showed efficacy in treating established cardiotoxicity.

Our findings provide a promising clinical approach for preventing and treating cardiotoxicity induced by ICIs, dissociating the antitumor efficacy of ICI-based therapies from their cardiotoxic side effects.

Inflammatory diseases impair the reparative properties of endothelial progenitor cells (EPC); however, the involvement of diabetes in EPC dysfunction associated with myocardial infarction (MI) remains unknown.

A model was established combining high-fat diet (HFD)/streptozotocin (STZ)-induced diabetic mice with myocardial infarction. The therapeutic effects of transplanted wild-type EPC, Nlrp3 knockout EPC, and Nlrp3 overexpression EPC were evaluated. Chip and Luciferase assay revealed CEBPB regulated the transcriptional expression of Nlrp3 as a transcription factor in EPC stimulated by high glucose (HG) or advanced glycation end products (AGEs). CO-IP results suggested that USP14 selectively suppressed NLRP3 degradation. KEGG enrichment revealed PI3K/ Akt/mTOR signaling showed striking significance in the entire pathway.

In our study, wild-type, Nlrp3 knockout and Nlrp3 overexpressed EPC, intracardiac injections effectively improved cardiac function, increased angiogenesis, and reduced infarct size in mice with myocardial infarction. However, in the HFD/STZ-induced diabetic mice model combined with myocardial infarction, Nlrp3 knockout EPC significantly restored angiogenic capacity. Mechanically, CEBPB regulated the transcriptional level of Nlrp3 as a transcription factor in EPC. Meanwhile, we found that USP14 selectively suppressed NLRP3 protein degradation through the USP motif on the NACHT domain in mediating inflammasome activation. Cardiac functional outcomes in recipient mice after intramyocardial injection of shNlrp3 EPC overexpressing CEBPB or USP14 validated the modulation of EPC function by regulating Nlrp3 transcription or post-translational modification. Furthermore, KEGG enrichment and validation at the protein levels revealed PI3K/ Akt/mTOR cascade might be a downstream signal for NLRP3 inflammasome.

Our study provides a new understanding of how diabetes affected progenitor cell-mediated cardiac repair and identifies NLRP3 as a new therapeutic target for improving myocardial infarction repair in inflammatory diseases.

Estrogen deficiency and Diabetes mellitus (DM) cause joint tissue deterioration, although the mechanisms are uncertain. This study evaluated the immunoexpression of autophagy and NLRP3-inflammasome markers, in rat articular cartilage with estrogen deficiency and DM.

Twenty rats were sham-operated (SHAM) or ovariectomized (OVX) and equally allocated into four groups: SHAM and OVX groups administered with vehicle solution; SHAM and OVX groups treated with 60 mg/kg/body weight of streptozotocin, intraperitoneally, to induce DM (SHAM-DM and OVX-DM groups). After seven weeks, the rats were euthanized, and their joint knees were processed for paraffin embedding. Sections were stained with haematoxylin-eosin, toluidine blue, safranin-O/fast-green or subjected to picrosirius-red-polarisation method; immunohistochemistry to detect beclin-1 and microtubule-associated protein 1B-light chain 3 (autophagy markers), NLRP3 and interleukin-1β (IL-1β) (inflammasome activation markers), along with matrix metalloproteinase-9 (MMP-9), Nuclear factor-kappa B (NFκB), and Vascular endothelial growth factor A (VEGF-A) were performed.

Deterioration of articular cartilage and subchondral bone were greater in SHAM-DM and OVX-DM groups. Higher percentages of immunolabeled chondrocytes to NLRP3, IL-1β, MMP-9, NFκB, and VEGF-A, as well as lower percentages of chondrocytes immunolabeled to autophagy markers, were noticed in estrogen-deficient and diabetic groups. These differences were greater in the OVX-DM group. Percentages of immunolabeled chondrocytes showed negative correlation between autophagy markers v.s IL-1β, NLRP-3, MMP-9, NFκB, and VEGF-A, along with positive correlation between VEGF-A vs. MMP-9, NFκB, IL-1β, and NLRP3, and MMP-9 vs. NFκB.

In conclusion, autophagy reduction and NLRP3 inflammasome activation in chondrocytes may be implicated in articular cartilage degradation, under estrogen-deficient and DM conditions. Moreover, the combination of estrogen deficiency and DM may potentiate those effects.