Role of the inflammasome in insulin resistance and type 2 diabetes mellitus

Expression and correlation analysis of silent information regulator 1 (SIRT1), sterol regulatory element-binding protein-1 (SREBP1), and pyroptosis factor in gestational diabetes mellitus

BACKGROUND AND AIM

Globally, the prevalence of gestational diabetes mellitus (GDM) is rising each year, yet its pathophysiology is still unclear. To shed new light on the pathogenesis of gestational diabetes mellitus and perhaps uncover new therapeutic targets, this study looked at the expression levels and correlations of SIRT1, SREBP1, and pyroptosis factors like NLRP3, Caspase-1, IL-1, and IL-18 in patients with GDM.

METHODS

This study involved a comparative analysis between two groups. The GDM group consisted of 50 GDM patients and the control group included 50 pregnant women with normal pregnancies. Detailed case data were collected for all participants. We utilized real-time quantitative PCR and Western Blot techniques to assess the expression levels of SIRT1 and SREBP1 in placental tissues from both groups. Additionally, we employed an enzyme-linked immunosorbent assay to measure the serum levels of SIRT1, SREBP1, and pyroptosis factors, namely NLRP3, Caspase-1, IL-1β, and IL-18, in the patients of both groups. Subsequently, we analyzed the correlations between these factors and clinical.

RESULTS

The results showed that there were significantly lower expression levels of SIRT1 in both GDM group placental tissue and serum compared to the control group (p < 0.01). In contrast, the expression of SREBP1 was significantly higher in the GDM group than in the control group (p < 0.05). Additionally, the serum levels of NLRP3, Caspase-1, IL-1β, and IL-18 were significantly elevated in the GDM group compared to the control group (p < 0.01). The expression of SIRT1 exhibited negative correlations with the expression of FPG, OGTT-1h, FINS, HOMA-IR, SREBP1, IL-1β, and IL-18. However, there was no significant correlation between SIRT1 expression and OGTT-2h, NLRP3, or Caspase-1. On the other hand, the expression of SREBP1 was positively correlated with the expression of IL-1β, Caspase-1, and IL-18, but has no apparent correlation with NLRP3.

CONCLUSIONS

Low SIRT1 levels and high SREBP1 levels in placental tissue and serum, coupled with elevated levels of pyroptosis factors NLRP3, Caspase-1, IL-1β, and IL-18 in serum, may be linked to the development of gestational diabetes mellitus. Furthermore, these three factors appear to correlate with each other in the pathogenesis of GDM, offering potential directions for future research and therapeutic strategies.

Review on the role of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome pathway in diabetes: mechanistic insights and therapeutic implications

This review explores the pivotal role of the nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3) inflammasome in the pathogenesis of diabetes and its complications, highlighting the therapeutic potential of various oral hypoglycemic drugs targeting this pathway. NLRP3 inflammasome activation, triggered by metabolic stressors like hyperglycemia, hyperlipidemia, and free fatty acids (FFAs), leads to the release of pro-inflammatory cytokines interleukin-1β and interleukin-18, driving insulin resistance, pancreatic β-cell dysfunction, and systemic inflammation. These processes contribute to diabetic complications such as nephropathy, neuropathy, retinopathy, and cardiovascular diseases (CVD). Here we discuss the various transcriptional, epigenetic, and gut microbiome mediated regulation of NLRP3 activation in diabetes. Different classes of oral hypoglycemic drugs modulate NLRP3 inflammasome activity through various mechanisms: sulfonylureas inhibit NLRP3 activation and reduce inflammatory cytokine levels; sodium-glucose co-transporter 2 inhibitors (SGLT2i) suppress inflammasome activity by reducing oxidative stress and modulating intracellular signaling pathways; dipeptidyl peptidase-4 inhibitors mitigate inflammasome activation, protecting against renal and vascular complications; glucagon-like peptide-1 receptor agonists attenuate NLRP3 activity, reducing inflammation and improving metabolic outcomes; alpha-glucosidase inhibitors and thiazolidinediones exhibit anti-inflammatory properties by directly inhibiting NLRP3 activation. Agents that specifically target NLRP3 and inhibit their activation have been identified recently such as MCC950, Anakinra, CY-09, and many more. Targeting the NLRP3 inflammasome, thus, presents a promising strategy for managing diabetes and its complications, with oral hypoglycemic drugs offering dual benefits of glycemic control and inflammation reduction. Further research into the specific mechanisms and long-term effects of these drugs on NLRP3 inflammasome activity is warranted.

Gender differences in the relationship between the triglyceride-glucose index and serum Klotho concentrations among the middle-aged and elderly: a cross-sectional analysis

BACKGROUND

The triglyceride-glucose (TyG) index is recognized as a robust indicator for evaluating insulin resistance (IR). Despite the well-documented anti-aging biological functions of Klotho protein, its correlation with the TyG index remains unexplored.

METHODS

A cross-sectional analysis was conducted involving participants from the National Health and Nutrition Examination Surveys (NHANES) 2007-2016. The TyG index was computed using laboratory data, while serum Klotho concentrations was determined using ELISA kit. After adjusting potential confounding variables, multivariate regression models were employed to evaluate the association between the TyG index and Klotho protein levels among middle-aged and elderly females and males separately. Additionally, smooth curve fitting and segmented regression model were applied to investigate potential threshold effects and identify the inflection point.

RESULTS

A total of 6,573 adults qualified for inclusion, comprising 3,147 (47.88%) males and 3,426 (52.12%) females. Multivariate regression analysis revealed that females with a higher TyG index exhibited significantly lower serum Klotho concentrations (β=-83.41, 95% CI: -124.23 to -42.60, P < 0.0001). This association was not statistically significant in males (β = 15.40, 95% CI: -19.16 to 49.95, P = 0.3827). Subgroup analyses revealed a significant interaction effect by diabetes status in females (P-interaction = 0.0121), where non-diabetic females showed a stronger negative association between TyG index and serum Klotho levels compared to diabetic females. In the female group, when TyG index was divided into quartiles, individuals in the highest quartile of TyG index exhibited reduced levels of Klotho protein (Q4: -88.77 pg/ml) compared to those in the lowest quartile (Q1) after full adjustment (P = 0.0041). Segmented regression analysis indicated a turning point value of 9.4 in females. Notably, a 1-unit increase in TyG index was significantly associated with a decrease in Klotho levels by -111.43 pg/ml (95% CI: -157.34 to -65.52, P < 0.0001) when TyG index was below 9.4, while above this threshold, the association was not significant (Log likelihood ratio test: 0.009).

CONCLUSIONS

The findings highlight a non-linear correlation between the TyG index and serum Klotho concentrations among females, indicative of a saturation effect. This relationship was particularly pronounced in non-diabetic women. In contrast, no statistically significant association was observed in male participants.

DNA sensors in metabolic and cardiovascular diseases: Molecular mechanisms and therapeutic prospects

DNA sensors generally initiate innate immune responses through the production of type I interferons. While extensively studied for host defense against invading pathogens, emerging evidence highlights the involvement of DNA sensors in metabolic and cardiovascular diseases. Elevated levels of modified, damaged, or ectopically localized self-DNA and non-self-DNA have been observed in patients and animal models with obesity, diabetes, fatty liver disease, and cardiovascular disease. The accumulation of cytosolic DNA aberrantly activates DNA signaling pathways, driving the pathological progression of these disorders. This review highlights the roles of specific DNA sensors, such as cyclic AMP-GMP synthase and stimulator of interferon genes (cGAS-STING), absent in melanoma 2 (AIM2), toll-like receptor 9 (TLR9), interferon gamma-inducible protein 16 (IFI16), DNA-dependent protein kinase (DNA-PK), and DEAD-box helicase 41 (DDX41) in various metabolic disorders. We explore how DNA signaling pathways in both immune and non-immune cells contribute to the development of these diseases. Furthermore, we discuss the intricate interplay between metabolic stress and immune responses, offering insights into potential therapeutic targets for managing metabolic and cardiovascular disorders. Understanding the mechanisms of DNA sensor signaling in these contexts provides a foundation for developing novel interventions aimed at mitigating the impact of these pervasive health issues.

Exploring Therapeutic Potential of Phytoconstituents as a Gut Microbiota Modulator in the Management of Neurological and Psychological Disorders

The functioning of the brain and its impact on behavior, emotions, and cognition can be affected by both neurological and psychiatric disorders that impose a significant burden on global health. Phytochemicals are helpful in the treatment of several neurological and psychological disorders, including anxiety, depression, Huntington's disease (HD), Parkinson's disease (PD), Alzheimer's disease (AD), and autism spectrum disorder (ASD), because they have symptomatic benefits with few adverse reactions. Changes in gut microbiota have been associated with many neurological and psychiatric conditions. This review focuses on the potential efficacy of phytochemicals such as flavonoids, terpenoids, and polyphenols in regulating gut flora and providing symptomatic relief for a range of neurological and psychological conditions. Evidence-based research has shown the medicinal potentials of these phytochemicals, but additional study is required to determine whether altering gut microbiota might slow the advancement of neurological and psychological problems.

Investigating the causal association between gut microbiota and type 2 diabetes: a meta-analysis and Mendelian randomization

Background

Studies have shown that gut dysbiosis contributes to the pathophysiology of type 2 diabetes mellitus (T2DM). Identifying specific gut microbiota dysbiosis may provide insight into the pathogenesis of T2DM.

Purpose

This study investigated the causal relationship between gut microbiota and T2DM using meta-analysis and Mendelian randomization (MR).

Methods

In the first part, we searched for literature on gut microbiota and T2DM, and conducted a meta-analysis. We observed differences in glycosylated hemoglobin and fasting blood glucose levels in both groups. Second, we obtained GWAS data from genome-wide association study database 19 (GWAS). We used two-sample MR analysis to verify the forward and reverse causal associations between gut microbiota and T2DM. Additionally, we selected the European GWAS data from the European Bioinformatics Institute (EBI) as a validation set for external validation of the MR analysis. In the third part, we aimed to clarify which gut microbiota contribute to the degree of causal association between group disorders and T2DM through multivariate MR analysis and Bayesian model averaging (MR-BMA).

Results

1. According to the meta-analysis results, the glycated hemoglobin concentration in the gut probiotic intervention group was significantly lower than in the control group. Following treatment, fasting blood glucose levels in the intervention group were significantly lower than those in the control group. 2. The results of two samples MR analysis revealed that there were causal relationships between six gut microbiota and T2DM. Genus Haemophilus and order Pasteurellaceae were negatively correlated with T2DM. Genus Actinomycetes, class Melanobacteria and genus Lactobacillus were positively correlated. Reverse MR analysis demonstrated that T2DM and gut microbiota did not have any reverse causal relationship. The external validation data set showed a causal relationship between gut microbiota and T2DM. 3. Multivariate MR analysis and MR-BMA results showed that the independent genus Haemophilus collection had the largest PP.

Conclusion

Our research results suggest that gut microbiota is closely related to T2DM pathogenesis. The results of further MR research and an analysis of the prediction model indicate that a variety of gut microbiota disorders, including genus Haemophilus, are causally related to the development of T2DM. The findings of this study may provide some insight into the diagnosis and treatment of T2DM.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO.

Pyroptosis in Diabetic Peripheral Neuropathy and its Therapeutic Regulation

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

Exploring the Potential of Ribes nigrum L., Aronia melanocarpa (Michx.) Elliott, and Sambucus nigra L. Fruit Polyphenol-Rich Composition and Metformin Synergy in Type 2 Diabetes Management

Type 2 diabetes, characterized by insulin resistance and impaired glucose homeostasis, is commonly managed through lifestyle interventions and medications such as metformin. Although metformin is generally well-tolerated, it may cause gastrointestinal adverse effects and, in rare cases, precipitate lactic acidosis, necessitating cautious use in individuals with renal dysfunction. Additionally, concerns regarding its impact on hepatic function have led to its discontinuation in cirrhotic patients. This study explores the potential synergistic benefits of a polyphenol-rich blend containing black currant, chokeberry, and black elderberry extracts alongside metformin in managing type 2 diabetes. In vitro results highlighted distinct effects of AMPK pathway modulation, showcasing reductions in cholesterol and triglyceride levels alongside a notable enhancement in glucose uptake. The blend, when combined with metformin, significantly reduced insulin levels and fasting glucose concentrations in an in vivo model. Furthermore, hepatic analyses unveiled a modulation in cellular pathways, suggesting a potential influence on lipid metabolism, attenuation of inflammatory pathways, a decrease in cellular stress response, and antioxidant defense mechanisms, collectively implying a potential reduction in liver fat accumulation. The findings suggest a potential complementary role of polyphenols in enhancing the efficacy of metformin, possibly allowing for reduced metformin dosage and mitigating its side effects. Further clinical studies are warranted to validate these findings and establish the safety and efficacy of this nutraceutical approach in managing type 2 diabetes.

Cuproptosis: potential new direction in diabetes research and treatment

Cuproptosis, a recently discovered form of cell death, stems from an overabundance of copper ions infiltrating mitochondria. These ions directly engage lipoylated proteins, prompting their oligomerization and subsequent loss of iron-sulfur clusters. This sequence induces proteotoxic stress, ultimately culminating in cell death. Type 2 diabetes, a chronic metabolic disorder resulting from a complex interplay of genetic and environmental factors, has not yet been fully understood in terms of its etiology and pathogenesis. Intricately, it is linked to various modalities of cell death, including mitochondrial autophagy, apoptosis, pyroptosis, and ferroptosis. Studies have discovered impaired copper metabolism in individuals with Type 2 diabetes, hinting at a unique role for copper homeostasis in the progression of the disease. To this end, the present research aims to delineate the potential correlation between cuproptosis and Type 2 diabetes by exhaustively reviewing the existing literature. By synthesizing relevant research on cuproptosis, the paper intends to lay the groundwork for a thorough exploration of the pathogenesis of Type 2 diabetes and the development of targeted therapeutic interventions. The ultimate objective is to facilitate a deeper understanding of Type 2 diabetes and to identify novel therapeutic strategies associated with cuproptosis.

Visceral fat area is more strongly associated with arterial stiffness than abdominal subcutaneous fat area in Chinese patients with type 2 diabetes

BACKGROUND

Few studies have compared the correlation between visceral fat area (VFA) and abdominal subcutaneous fat area (SFA) with arterial stiffness (AS) in patients with type 2 diabetes (T2D). In addition, there is currently controversy regarding the correlation between VFA and SFA with AS. We aimed to investigate the relationship between VFA and SFA with AS in patients with T2D.

METHODS

In this cross-sectional study, 1475 Chinese T2D patients with an average age of 52.32 ± 10.96 years were included. VFA and SFA were determined by a dual bioelectrical impedance analyzer, and AS was determined by measurement of brachial-ankle pulse wave conduction velocity (baPWV). Atherosclerosis was deemed present in study participants with baPWV values higher than 75th percentile (1781 cm/s). Independent correlations of logVFA and logSFA with AS were assessed using multiple linear regression and multivariate logistic regression.

RESULTS

The baPWV was linked with VFA, waist circumference, and women's SFA in a general linear correlation study (P < 0.05), but not with body mass index (P = 0.3783) or men's SFA (P = 0.1899). In both men and women, VFA and SFA were positively correlated with AS, according to the generalized additive model (GAM). After fully adjusting for confounders, multiple linear regression analyses showed that for every 1-unit increase in logVFA, the beta coefficient of baPWV increased by 63.1 cm/s (95% CI: 18.4, 107.8) (P < 0.05). logSFA did not correlate significantly with baPWV (P = 0.125). In the multiple logistic regression analysis, the odds ratio (OR) of elevated baPWV was 1.8 (95% CI: 1.1, 3.1) (P = 0.019) per 1-unit increase in logVFA. logSFA did not correlate significantly with AS (P = 0.091). In the subgroup analysis, the correlation between logVFA and baPWV did not interact across subgroups (P-interaction > 0.05).

CONCLUSIONS

Compared with SFA, VFA had a stronger independent positive correlation with AS in Chinese T2D patients. Patients with T2D should pay more attention to monitoring VFA and lowering it to minimize cardiovascular events.

NLRP6 deficiency inhibits neuroinflammation and ameliorates brain injury in ischemic stroke by blocking NLRs inflammasomes activation through proteasomal degradation of pro-caspase-1

Innate inflammation is crucial for ischemic stroke development. NLRP6, a nucleotide-binding and oligomerization domain-like receptors (NLRs) family member, regulates innate inflammation. Whether NLRP6 regulates neurological damage and neuroinflammation during ischemic stroke remains unclear. We report that NLRP6 is abundantly expressed in microglia and significantly upregulated in the ischemic brain. The brain injury severity was alleviated in NLRP6-deficient mice after ischemic stroke, as evidenced by reduced cerebral infarct volume, decreased neurological deficit scores, improved histopathological morphological changes, ameliorated neuronal denaturation, and relief of sensorimotor dysfunction. In the co-culture OGD/R model, NLRP6 deficiency prevented neuronal death and attenuated microglial cell injury. NLRP6 deficiency blocked several NLRs inflammasomes' activation and abrogated inflammasome-related cytokine production by decreasing the expression of the common effector pro-caspase-1. NLRP6 deficiency reduced pro-caspase-1's protein level by inducing proteasomal degradation. These findings confirm the neuroprotective role of NLRP6 deficiency in ischemic stroke and its underlying regulation mechanism in neuroinflammation and provide a potential therapeutic target for ischemic stroke.

NU6300 covalently reacts with cysteine-191 of gasdermin D to block its cleavage and palmitoylation

Gasdermin D (GSDMD) serves as a vital mediator of inflammasome-driven pyroptosis. In our study, we have identified NU6300 as a specific GSDMD inhibitor that covalently interacts with cysteine-191 of GSDMD, effectively blocking its cleavage while not affecting earlier steps such as ASC oligomerization and caspase-1 processing in AIM2- and NLRC4-mediated inflammation. On the contrary, NU6300 robustly inhibits these earlier steps in NLRP3 inflammasome, confirming a unique feedback inhibition effect in the NLRP3-GSDMD pathway upon GSDMD targeting. Our study reveals a previously undefined mechanism of GSDMD inhibitors: NU6300 impairs the palmitoylation of both full-length and N-terminal GSDMD, impeding the membrane localization and oligomerization of N-terminal GSDMD. In vivo studies further demonstrate the efficacy of NU6300 in ameliorating dextran sodium sulfate-induced colitis and improving survival in lipopolysaccharide-induced sepsis. Overall, these findings highlight the potential of NU6300 as a promising lead compound for the treatment of inflammatory diseases.

Association of salivary levels of DNA sensing inflammasomes AIM2, IFI16, and cytokine IL18 with periodontitis and diabetes

BACKGROUND

Aberrant deoxyribonucleic acid (DNA) contributes to inflammasome orchestrated progression of chronic inflammatory diseases like diabetes and periodontitis. The purpose of the present study was to estimate salivary levels of DNA sensing inflammasomes, absent in melanoma 2 (AIM2), interferon γ inducible protein (IFI16), and cytokine interleukin 18 (IL18) in individuals with periodontitis, diabetes, and healthy controls and interpret its association with periodontal and diabetic parameters.

METHODS

Salivary levels of AIM2, IFI16, and IL18 were estimated by enzyme linked immunosorbent assay (ELISA) in a total of 120 individuals (n = 30 in each group), namely, healthy (Group 1), periodontitis (Group 2), diabetes (Group 3), and diabetes with periodontitis (Group 4). Correlations of inflammasome levels and periodontal clinical parameters-plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), clinical attachment level (CAL), and periodontal inflamed surface area (PISA) were performed. Multiple regression was carried out to predict AIM2 and IFI16 with various independent variables.

RESULTS

The mean salivary levels of AIM2, IFI16, and IL18 were highest in diabetes with periodontitis (Group 4) and least in healthy (Group 1) and statistically significant between the groups (p = 0.000). Significant positive correlation between clinical periodontal parameters and AIM2, IFI16, and IL18 was present (p ≤ 0.05). Multiple regression showed glycated hemoglobin (HbA1C) (p = 0.002), GI (p = 0.016), PISA (p = 0.002), and CAL (p = 0.004) were significant predictors of AIM2, while HbA1C (p = 0.012), PISA (p = 0.003), and CAL (p = 0.007) predicted IFI16.

CONCLUSION

The results of the present study showed higher levels of AIM2, IFI16, and IL18 in saliva of individuals with diabetes and periodontitis. HbA1C, PISA, and CAL were significant independent predictors of salivary AIM2 and IFI16 levels.

Positive correlation between lipid accumulation product index and arterial stiffness in Chinese patients with type 2 diabetes

Background

Many studies have confirmed that lipid accumulation products (LAP) predict arterial stiffness (AS) in hypertensive patients. But there is little research on the use of LAP in identifying early atherosclerosis in patients with type 2 diabetes mellitus (T2DM). The aim of this study was to determine the relationship between the LAP index and brachial-ankle pulse wave velocity (baPWV) in Chinese patients with T2DM.

Methods

A total of 1471 Chinese participants with T2DM, ranging in age from 18 to 80, were included in this cross-sectional study. BaPWV measurements were used to calculate the AS. A baPWV greater than the 75th percentile (1700 cm/s) was defined as indicating increased AS. The LAP index was calculated from the combination of waist circumference (WC) and triglycerides (TG).

Results

According to the quartiles of the LAP index, baPWV tended to increase after adjusting for sex and age. Multiple linear regression analysis showed that the beta coefficient (β) of baPWV increased by 31.0 cm/s for each unit of lnLAP that was increased, and the 95% confidence interval (CI) was (6.5, 55.5) cm/s. In multivariate logistic regression analyses, after fully adjusting for confounders, the risk of elevated baPWV increased with each unit increase in lnLAP, with an odds ratio (OR) of 1.3 (95% CI: 1.0, 1.8). According to the generalized additive model (GAM), we found that lnLAP was positively correlated with baPWV and baPWV elevation. The results were the same for males and females. Subgroup analyses showed that the positive correlation between lnLAP and elevated baPWV did not interact across all subgroups.

Conclusions

In Chinese patients with T2DM, LAP was strongly and positively correlated with baPWV and elevated baPWV.

Influences of vitiligo-associated characteristics on the occurrence of diabetes mellitus: Interactive analysis of a cross-sectional study

The risk of diabetes mellitus (DM) in vitiligo patients is higher than that in non-vitiligo population. Our goal was to explore the influencing factors for DM in vitiligo patients. A matched-pair design of 107 cases with DM and 428 controls without DM was conducted among vitiligo patients in Xijing hospital from January 2010 to October 2021. The baseline characteristics of patients were analysed based on standard descriptive statistics. The vitiligo-associated characteristics were analysed by logistic regression to identify influencing factors of DM. Interaction analysis was performed to explore the additive interactions between vitiligo-associated characteristics and baseline characteristics. After adjustment for the baseline characteristics, the severity of vitiligo [odds ratio (OR) = 2.47, 95% confidence interval (CI): 1.47-4.14] and onset age of vitiligo (OR = 0.98, 95% CI: 0.97-0.99) had a significant correlation with occurrence of DM. The severity of vitiligo had additive interaction with family history of diabetes [relative excess risk due to interaction (RERI) = 132.51 (95% CI: 5.51-1100.20), attributable proportion (AP) = 0.91 (95% CI: 0.17-0.95), synergy index (S) = 11.53 (95% CI: 1.32-100.5)] and with smoking history [RERI = 6.54 (95% CI: 0.67-19.83), AP = 0.64 (95% CI: 0.04-0.80), S = 3.48 (95% CI: 1.17-10.36)]. Earlier onset age of vitiligo and greater BSA involvement might be two independent risk factors for DM in vitiligo patients. Interaction assessment identified the severity of vitiligo as additive interaction factors with diabetes family history and with smoking history for the DM occurrence.

From Innate Immunity to Metabolic Disorder: A Review of the NLRP3 Inflammasome in Diabetes Mellitus

The role of the NLRP3 inflammasome is pivotal in the pathophysiology and progression of diabetes mellitus (DM), encompassing both type 1 (T1D), or type 2 (T2D). As part of the innate immune system, NLRP3 is also responsible for the chronic inflammation triggered by hyperglycemia. In both conditions, NLRP3 facilitates the release of interleukin-1β and interleukin-18. For T1D, NLRP3 perpetuates the autoimmune cascade, leading to the destruction of pancreatic islet cells. In T2D, its activation is associated with the presence of insulin resistance. NLRP3 activation is also instrumental for the presence of numerous complications associated with DM, microvascular and macrovascular. A considerable number of anti-diabetic drugs have demonstrated the ability to inhibit the NLRP3 inflammasome.

The NLRP3 inflammasome rs35829419 C>A polymorphism is associated with type 2 diabetes mellitus in Saudi Arabia

OBJECTIVES

To investigate the frequency of NLRP3 gene rs35829419 C>A single-nucleotide polymorphism (SNP) in a Saudi Arabian population from Jazan (Southwest Saudi Arabia) and test its potential association with type 2 diabetes mellitus (T2DM).

METHODS

This case-control study included 546 volunteers (271 patients with T2DM and 275 healthy controls) recruited from outpatient clinics at Jazan University Hospital and King Fahad Central Hospital in Jazan, Saudi Arabia, between December 2021 and July 2022. Genomic DNA was extracted from all samples and genotyped for the NLRP3 rs35829419 C>A SNP using TaqMan technology. The association between the NLRP3 rs35829419 polymorphism and T2DM was examined using logistic regression analysis.

RESULTS

Overall genotype distributions were 90.5% (CC), 9.3% (CA), and 0.2% (AA). The heterozygous CA genotype was more frequent in T2DM group (12.2%) compared to the control group (6.5%) and logistic regression analysis showed a statically significant association with T2DM risk under codominant (CA versus CC; odds ratio [OR]=1.99; 95% confidence interval [CI]= [1.11-3.61]; p=0.0270), and dominant (CA+AA versus CC; OR=2.05; CI=[1.16-3.75]; p=0.019) models of inheritance.

CONCLUSION

This study revealed the frequency of NLRP3 rs35829419 C>A polymorphism in our population and showed a direct correlation between having the minor allele for A and having a higher risk of developing T2DM. This study highlights the significance of NLRP3 rs35829419 C>A polymorphism in the pathophysiology of T2DM.

Reframing the link between metabolism and NLRP3 inflammasome: therapeutic opportunities

Inflammasomes are multiprotein signaling platforms in the cytosol that senses exogenous and endogenous danger signals and respond with the maturation and secretion of IL-1β and IL-18 and pyroptosis to induce inflammation and protect the host. The inflammasome best studied is the Nucleotide-binding oligomerization domain, leucine-rich repeat-containing family pyrin domain containing 3 (NLRP3) inflammasome. It is activated in a two-step process: the priming and the activation, leading to sensor NLRP3 oligomerization and recruitment of both adaptor ASC and executioner pro-caspase 1, which is activated by cleavage. Moreover, NLRP3 inflammasome activation is regulated by posttranslational modifications, including ubiquitination/deubiquitination, phosphorylation/dephosphorylation, acetylation/deacetylation, SUMOylation and nitrosylation, and interaction with NLPR3 protein binding partners. Moreover, the connection between it and metabolism is receiving increasing attention in this field. In this review, we present the structure, functions, activation, and regulation of NLRP3, with special emphasis on regulation by mitochondrial dysfunction-mtROS production and metabolic signals, i.e., metabolites as well as enzymes. By understanding the regulation of NLRP3 inflammasome activation, specific inhibitors can be rationally designed for the treatment and prevention of various immune- or metabolic-based diseases. Lastly, we review current NLRP3 inflammasome inhibitors and their mechanism of action.