姜黄素对糖尿病大鼠心肌的保护作用*

 目的： 研究姜黄素对糖尿病大鼠心肌的保护作用及可能机制。方法: 雄性Wistar大鼠75只，随机抽取10只大鼠作为正常对照组，其余65只大鼠给予高糖高脂饮食喂养8周后腹腔注射链脲佐菌素40 mg/kg，给药72 h和7 d空腹血糖≥11.6 mmol/L为糖尿病模型成功大鼠。糖尿病大鼠随机分为糖尿病心肌病组、姜黄素小剂量治疗组和大剂量治疗组。测定心肌谷胱甘肽过氧化物酶（GSH-Px）活性和丙二醛（MDA）含量，酶联免疫吸附试验检测血清心肌钙蛋白I（cTnI）的变化，Western blotting检测蛋白激酶C（PKC）蛋白表达。结果: 姜黄素治疗后可明显改善糖尿病所致的动物体重下降和空腹血糖升高，抑制心肌中MDA的产生并升高GSH-Px活性，减少血清中cTnI的释放，下调心肌组织PKC蛋白表达。结论: 姜黄素对大鼠糖尿病心肌病具有保护作用，其机制可能与抑制氧化应激有关。

Protective effect of curcumin on myocardium in diabetic rats

AIM: To study the effects of curcumin (Cur) on diabetic cardiomyopathy (DCM) in rats. METHODS: Male Wistar rats (n=75) were divided into control group and diabetes model group, in which the rats were fed with high-fat diet and then intraperitoneally injected with streptozotocin (STZ, 40 mg/kg). Fasting blood glucose was measured 72 h and 1 week after STZ injection. The diabetic rats were diagnosed when sustained fasting blood glucose levels ≥ 11.6 mmol/L. The diabetic rats were randomly divided into DCM group, DCM+Cur 100 mg/kg group and DCM+Cur 200 mg/kg group. After treatment for 16 weeks, glutathione peroxidase (GSH-Px) activity and malondialdehyde (MDA) level were measured, and the level of cardiac troponin I (cTnI) in the serum was determined by enzyme-linked immunosorbent assay. The protein expression of protein kinase C (PKC) was detected by Western blotting. RESULTS: Curcumin significantly decreased the blood glucose level, increased the body weight, inhibited MDA content and up-regulated the GSH-Px activity in the diabetic rats. Furthermore, curcumin treatment inhibited the diabetes-induced protein expression of PKC. CONCLUSION: Curcumin may have a protective effect on diabetic cardiomyopathy by attenuating oxidative stress.