Targeting the cGAS-STING Pathway to Modulate Immune Inflammation in Diabetes and Cardiovascular Complications: Mechanisms and Therapeutic Insights.

Type 2 diabetes mellitus (T2DM), characterized by insulin resistance and chronic hyperglycemia, markedly increases the incidence and mortality of cardiovascular disease (CVD). Emerging preclinical evidence identifies the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway as a critical mediator of diabetic cardiovascular inflammation. Metabolic stressors in T2DM-hyperglycemia, lipotoxicity, and mitochondrial dysfunction-induce leakage of mitochondrial and microbial double-stranded DNA into the cytosol, where it engages cGAS and activates STING. Subsequent TBK1/IRF3 and NF-κB signaling drives low-grade inflammation across cardiomyocytes, endothelial cells, macrophages, and fibroblasts. Genetic deletion of cGAS or STING in high-fat-diet-fed diabetic mice reduces NLRP3 inflammasome-mediated pyroptosis, limits atherosclerotic lesion formation, and preserves cardiac contractile performance. Pharmacological inhibitors, including RU.521 (cGAS antagonist), C-176/H-151 (STING palmitoylation blockers), and the TBK1 inhibitor amlexanox, effectively lower pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) and improve left ventricular ejection fraction in diabetic cardiomyopathy and ischemia-reperfusion injury models. Novel PROTAC degraders targeting cGAS/STING and natural products such as Astragaloside IV and Tanshinone IIA further support the pathway's druggability. Collectively, these findings position the cGAS-STING axis as a central molecular nexus linking metabolic derangement to cardiovascular pathology in T2DM and underscore its inhibition or targeted degradation as a promising dual cardiometabolic therapeutic strategy.