AIM To investigate the effects of curcumin (CUR) on myocardial injury and nuclear factor erythroid 2 related factor 2/ferroportin 1 (NRF2/FPN1) signaling pathway in rats with diabetes and coronary heart disease.

METHODS A rat model was constructed and randomly separated into model group, low, medium, and high-dose curcumin groups (CUR-L, CUR-M, CUR-H groups), and high-dose curcumin+pathway inhibitor ML385 group (CUR-H+ML385 group), with 12 rats in each group. An additional 12 healthy rats were selected as the control group. All rats were tested for blood biochemical indicators. Echocardiogram was applied to observe cardiac function indicators, HE staining was applied to observe the morphology of myocardial tissue, TUNEL staining was applied to observe the apoptosis of myocardial tissue cells and Western blot was applied to detect protein expression related to the NRF2/FPN1 signaling pathway.

RESULTS Compared with those in the control group, the overall structure of myocardial tissue in the model group was disrupted, with severe pathological damage, the myocardial cell apoptosis rate increased, FPG, TG, LPa, D-D and FIB levels, LVEDD and LVESD indicators and iron ion content were obviously increased, and INS level, HR and LVEF indicators and NRF2 and FPN1 protein expression levels were obviously reduced (P<0.05, P<0.01). Compared with those in the model group, with the increase of CUR dose, the overall structure of myocardial tissue in the CUR-L, CUR-M and CUR-H groups gradually recovered, pathological damage was reduced and the apoptosis rate of myocardial cells decreased. FPG, TG, LPa, D-D and FIB levels, LVEDD and, LVESD indicators and iron ion content were gradually reduced, and INS level, HR and LVEF indicators and NRF2 and FPN1 protein expression levels were gradually increased (P<0.05, P<0.01). Compared with those in the CUR-H group, the myocardial tissue of rats in the CUR-H+ML385 group showed overall structural rupture and more severe pathological damage, the myocardial cell apoptosis rate increased, FPG, TG, LPa, D-D and FIB levels, LVEDD and LVESD indicators and iron ion content were obviously increased, and INS level, HR and LVEF indicators and NRF2 and FPN1 protein expression levels were obviously reduced (P<0.01).

CONCLUSION Curcumin improves myocardial tissue damage and enhances cardiac protection function in rats with diabetes and coronary heart disease by activating NRF2/FPN1 signaling pathway.