Therapeutic Potential of Curcumin in Diabetic Cardiomyopathy: Modulation of Pyroptosis Pathways.

PURPOSE: Cardiac inflammation is a basic pathological process of diabetic cardiomyopathy (DCM). Inflammatory response is closely related to pyroptosis, which is a recently identified programmed cell death type. Curcumin (CUR) is a polyphenol extracted from turmeric and has been reported to be crucial in alleviating pyroptosis in DCM. However, the exact mechanism by which CUR improves pyroptosis remains unclear. Therefore, we aimed to investigate the effect of CUR on pyroptosis in DCM and explore the potential mechanisms.

METHODS: The molecular docking (MOD) analysis was performed using AutoDock Tools to evaluate the binding patterns and affinities between CUR and tripartite motif containing 21 (TRIM21), as well as between TRIM21 and gasdermin D (GSDMD). Subsequently, DCM models were established in Sprague-Dawley (SD) rats (in vivo) by administering streptozotocin (STZ) and feeding them a high-fat diet. In addition, H9C2 cells were cultured in a high glucose and palmitate environment to construct in vitro models of DCM. Rats or cells were treated by CUR directly. Subsequently, body weight (BW), heart weight (HW)/BW ratio, fasting blood glucose level, and lipid metabolism were measured. Pathological changes were analyzed using hematoxylin and eosin (H&E) and Masson staining. Small interfering RNA (si-RNA) was used to knockdown TRIM21 expression, and the pyroptosis protein expression and cellular activity were evaluated in different groups.

RESULTS: MOD analysis revealed that CUR had a strong binding affinity with TRIM21, and TRIM21 showed a robust interaction with GSDMD. STZ-induced diabetic SD rats showed metabolic abnormalities, structural changes in the ventricle, and the expression of TRIM21 and pyroptosis markers, including nod-like receptor protein-3 (NLRP3), Caspase-1, and GSDMD, were upregulated. CUR reduced cardiac remodeling and improved cardiac function in vivo. CUR inhibited pyroptosis by regulating TRIM21 through in vivo and in vitro studies.

CONCLUSION: CUR improves DCM by regulating TRIM21 expression to inhibit pyroptosis. Furthermore, this study provides novel approaches and experimental evidence for the research and treatment of DCM and presents new insights into its potential mechanisms.