Enhanced Cardiomyocyte NLRP3 Inflammasome-Mediated Pyroptosis Promotes d-Galactose-Induced Cardiac Aging.

BACKGROUND: Cardiac aging represents an independent risk factor for aging-associated cardiovascular diseases. Although evidence suggests an association between NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome formation and numerous cardiovascular diseases, its role in cardiac aging remains largely unclear. METHODS AND RESULTS: The longevity of mice with wild-type and NLRP3 knockout (NLRP3-/-) genotypes was assessed, with or without d-galactose treatment. Cardiac function was evaluated using echocardiography, and cardiac histopathology was examined through hematoxylin and eosin and Masson's trichrome staining. Senescence-associated ß-galactosidase (SA-ß-gal) staining was employed to detect cardiac aging. Western blotting was used to assess aging-related proteins (p53, p21) and pyroptosis-related proteins. Additionally, dihydroethidium staining, lactate dehydrogenase release, and interleukin-1ß ELISA assays were performed, along with measurements of total superoxide dismutase and malondialdehyde levels. In vitro, H9c2 cells were exposed to d-galactose for 24 hours in the absence or presence of N-acetyl-l-cysteine (reactive oxygen species inhibitor), BAY-117082 (nuclear factor κ-light-chain enhancer of activated B cells inhibitor), MCC950 (NLRP3 inhibitor), and VX-765 (Caspase-1 inhibitor). Immunofluorescence staining was employed to detect p53, gasdermin D, and apoptosis-associated speck-like protein proteins. Intracellular reactive oxygen species levels were assessed using fluorescence microscopy and flow cytometry. Senescence-associated ß-galactosidase staining and Western blotting were also employed in vitro for the same purpose. The results showed that NLRP3 upregulation was implicated in aging and cardiovascular diseases. Inhibition of NLRP3 extended life span, mitigated the aging phenotype, improved cardiac function and blood pressure, ameliorated lipid metabolism abnormalities, inhibited pyroptosis in cardiomyocytes, and ultimately alleviated cardiac aging. In vitro, the inhibition of reactive oxygen species, nuclear factor κ-light-chain enhancer of activated B cells, NLRP3, or caspase-1 attenuated NLRP3 inflammasome-mediated pyroptosis. CONCLUSIONS: The reactive oxygen species/nuclear factor κ-light-chain enhancer of activated B cells/NLRP3 signaling pathway loop contributes to d-galactose-treated cardiomyocyte senescence and cardiac aging.

Long-term insulin resistance is associated with frailty, frailty progression, and cardiovascular disease.

BACKGROUND: Insulin resistance and diabetes are associated with an increased risk of frailty, and frailty is associated with cardiovascular disease and premature mortality. We aim to investigate the impact of long-term insulin resistance trajectories on future frailty and cardiovascular risk among young adults. METHODS: In total, 3168 participants with a 30-year follow-up period. The baseline period covered the first 15 years as the exposure period. Insulin resistance was determined using the homeostasis model assessment for insulin resistance (HOMA-IR), and three trajectories (low, moderate, and high) were constructed. The subsequent 15 years constituted the event accrual period. Frailty was assessed using a deficit accumulation mode, and cardiovascular outcomes were obtained from the 15-year event accrual period. RESULTS: The mean age of all 3168 participants was 41.0 (37.0-43.0) years, with 1750 (55.2%) being women. Participants in the high level of insulin resistance trajectory had an increased prevalence of frailty (OR: 1.55, 95% CI: 1.05-2.30, P = 0.028). Although no statistically significant associations were observed after full adjustment, single-factor analysis indicated association between the moderate and high trajectories and frailty progression. Additionally, participants with high level of insulin resistance trajectory were associated with an increased risk of cardiovascular disease, coronary heart disease, and stroke. A notable correlation between HOMA-IR trajectory and cardiovascular diseases was still discernible within the subgroup where the frailty index ≥0.12 (HR: 2.12, 95% CI: 1.17-3.83, P = 0.013) (P for interaction >0.05). CONCLUSIONS: Long-term high level of insulin resistance is associated with high prevalence of frailty, and an increased risk of cardiovascular events. Emphasizing the importance of early prevention and intervention for abnormal glucose metabolism in young adults to prevent frailty and cardiovascular disease.

Long-Term High Level of Insulin Resistance Is Associated With an Increased Prevalence of Coronary Artery Calcification: The CARDIA Study.

Background Coronary artery calcification (CAC) is a crucial indicator of subclinical atherosclerotic cardiovascular disease. The relationship between long-term insulin resistance (IR) trajectory and CAC has been explored in few studies. Therefore, this study aimed to investigate whether the long-term IR time series of young adults are associated with the incidence of CAC in midlife. Methods and Results In a cohort study comprising 2777 participants from the CARDIA (Coronary Artery Risk Development in Young Adults) study, the homeostasis model assessment for IR was used to measure IR levels, and group-based trajectory modeling was used to fit three 25-year homeostasis model assessments for IR trajectories. Logistic regression was used to estimate the association between the 3 homeostasis model assessments for IR trajectories and CAC events at year 25. The results showed that among 2777 participants (mean age, 50.10±3.58 years; 56.2% women; 46.4% Black), there were 780 incident CAC events after a 25-year follow-up. After full adjustment, the prevalence of CAC was higher in the moderate- (odds ratio [OR], 1.40 [1.10-1.76]) and the high-level homeostasis model assessments for IR trajectories (OR, 1.84 [1.21-2.78]) than in the low-level trajectory. This association was observed in obese individuals despite the negative interaction between IR and different types of obesity (all P interactions >0.05). Conclusions Our study revealed that young adults with a higher level of IR were more likely to develop CAC in middle age. Furthermore, this association persisted in obese individuals. These findings highlight the importance of identifying subclinical cardiovascular risk factors and implementing primary prevention measures.

D-galactose-induced cardiac ageing: A review of model establishment and potential interventions.

Cardiovascular disease (CVD) is highly prevalent in an ageing society. The increased incidence and mortality rates of CVD are global issues endangering human health. There is an urgent requirement for understanding the aetiology and pathogenesis of CVD and developing possible interventions for preventing CVD in ageing hearts. It is necessary to select appropriate models and treatment methods. The D-galactose-induced cardiac ageing model possesses the advantages of low mortality, short time and low cost and has been increasingly used in the study of cardiovascular diseases in recent years. Therefore, understanding the latest progress in D-galactose-induced cardiac ageing is valuable. This review highlights the recent progress and potential therapeutic interventions used in D-galactose-induced cardiac ageing in recent years by providing a comprehensive summary of D-galactose-induced cardiac ageing in vivo and in vitro. This review may serve as reference literature for future research on age-related heart diseases.