姜黄素对糖尿病心肌病大鼠心肌细胞凋亡的影响

摘要

目的 观察姜黄素对糖尿病心肌病大鼠心肌细胞凋亡的影响.方法 将60只Wistar大鼠随机分为正常对照组、模型对照组和姜黄素小、大剂量组,每组15只.除正常对照组外,其他组建立大鼠1型糖尿病模型.姜黄素各剂量组灌胃姜黄素溶液;模型对照组与正常对照组灌胃等量0.9%氯化钠溶液.均每周2次,连续16周.取大鼠心脏行TUNEL凋亡染色,检测各组大鼠心肌细胞凋亡情况;Western blotting检测Bcl-2、Bax表达水平.结果 TUNEL凋亡染色结果显示,模型对照组大鼠心肌细胞出现不同程度凋亡.与正常对照组比较,模型对照组大鼠心肌细胞凋亡指数显著增加(P<0.05);与模型对照组比较,姜黄素各剂量组心肌细胞凋亡指数明显下降(P<0.05),且呈现剂量依赖性.Western blotting检测结果显示,模型对照组大鼠心肌细胞Bcl-2含量较正常对照组低,Bax含量较正常对照组高(P<0.01).与模型对照组比较,姜黄素各剂量组心肌细胞Bcl-2含量显著增加,Bax含量显著下降(P<0.01),且呈剂量依赖性.结论 姜黄素能显著降低1型糖尿病模型大鼠心肌Bax含量,升高Bcl-2含量,减少1型糖尿病所致大鼠心肌细胞凋亡.%Objective To investigate the preventive effect of curcumin on rats with myocardial apoptosis caused by type 1 diabetes. After intragastric administration of curcumin,the expression of genes related to apoptosis and the number of apoptotic myocardium cells were detected. Methods Sixty Wistar rats were randomly divided into 4 groups ( 15 rats per group ):diabetes group, normal control group,curcumin low dose and high dose group. Animal model with type 1 diabetes was induced by intraperitoneal single injection of streptozotocin ( STZ) in each group except the normal one. After two weeks of STZ injection,the rats with diabetes were used for this study. The curcumin treatment groups were treated with curcumin via intragastric administration for 16 weeks ( twice a week) . Normal control group and diabetes group were administrated with equivalent volume of saline. After 16 weeks, the experimental animals were sacrificed and their hearts were arrested after 0. 9% sodium chloride solution perfusion. The number of myocardial cell apoptosis was detected by TUNEL staining and the expressions of Bcl-2 and Bax relate to the cell apoptosis were examined by western blot analysis. Results The result of TUNEL staining was confirmed that the apoptosis index in the rats of diabetes group was significantly higher than the normal control group ( P<0.05) . However, there was a significantly decline of apoptosis index in the diabetes rats after the treatment of curcumin ( P<0.05) and the result showed a significant dose dependence of curcumin ( P<0.05) . The results of Western blot analysis confirmed that there was a significant lower expression of Bcl-2 and a higher expression and a higher expression of Bax in the hearts of diabetes rats compared with normal control rats (P<0.01). After the treatment of curcumin, the expression of anti-apoptosis protein Bcl-2 was significantly increased and the expression of pro-apoptosis protein Bax was obviously decreased in the myocardial cells of rats in curcumin treated group compared with the diabetes group (P<0.01). The result was also in a dose-dependent manner (P<0.05). Conclusion The treatment of curcumin can significantly increase the expression of anti-apoptosis protein Bcl-2 and decrease the expression of pro-apoptosis protein Bax,which induced the decrease of myocardial apoptosis in the heart of diabetes rats and could have the effects on the decline of myocardial apoptosis caused by diabetic cardiomyopathy.