Abstract: Objective To investigate the effect and mechanism of curcumin analogue H8 on cardiac structure and function in diabetic cardiomyopathy rats. Methods Twenty-four male SD rats were randomly divided into control group, model group and H8 group with 8 rats in each group. The model group and H8 group were given high-fat and high-sugar diet for 8 weeks and then intraperitoneally injected with streptozotocin (STZ) to establish the model of type 2 diabetes mellitus. H8 group was given H8 (6 mg/kg) for 4 weeks, while the control group and model group were given the same amount of sodium carboxymethylcellulose for 4 weeks. At the end of the 4th week, echocardiography was used to evaluate the cardiac structure and function of rats in each group. Then the rats were killed. The biochemical indexes, pathological changes of myocardium, lactate dehydrogenase (LDH), total superoxide dismutase (T-SOD) and malondialdehyde (MDA) contents in myocardium were measured. Results Compared with the control group, the left ventricular wall motion was weakened, ventricular remodeling was obvious, left ventricular ejection fraction (LVEF) and fractional shortening (FS) were decreased, blood sugar, total cholesterol and triglyceride levels were significantly increased, myocardial cell structure was disordered, the contents of LDH and MDA in myocardial tissues were significantly increased, and the content of T-SOD decreased significantly in the model group (P＜0.05). Compared with the model group, the left ventricular wall motion, ventricular remodeling, LVEF, FS and cardiac arrays were significantly improved, blood sugar, total cholesterol and triglyceride levels were significantly decreased, LDH and MDA in myocardial tissues decreased, the content of T-SOD increased significantly in the rats of H8 group (P＜0.05). Conclusion Curcumin analogue H8 has a protective effect on myocardial injury in diabetic rats. Its mechanism may be related to the inhibition of ventricular remodeling, improvement of cardiac function and reduction of blood glucose, blood lipid and oxidative stress factors.

Key words: diabetes mellitus, type 2, diabetic cardiomyopathies, curcumin, echocardiography, oxidative stress; curcumin analogues