Sirt1蛋白在风湿性心脏病大鼠心肌组织中的表达

The expression of Sirt1 protein in cardiac tissues of rats with rheumatic heart disease

目的:观察Ⅲ类组蛋白去乙酰基酶1(Sirt1)在灭活链球菌诱导的风湿性心脏病(RHD)大鼠心肌组织中的表达情况。方法:随机将Lewis大鼠分为急性RHD组(ARHD组)、慢性RHD组(CRHD组)和正常对照组(Control组)3组。以灭活链球菌刺激大鼠建立ARHD(7周)和CRHD(24周)模型。通过HE和Masson染色观察大鼠心肌和心瓣膜组织的病理变化,并利用免疫组化和Western blotting检测心肌组织中Sirt1的表达情况。结果:病理结果显示ARHD组心肌及瓣膜组织炎症细胞浸润明显,CRHD组心肌散在炎症细胞浸润且瓣膜明显纤维化;与Control组相比,ARHD组和CRHD组心肌组织Sirt1蛋白表达均上调(P<0.01,P<0.05),且ARHD组高于CRHD组(P<0.01);此外,与Control组相比,ARHD组和CRHD组心肌细胞核内Sirt1蛋白表达均呈上调趋势(均P<0.01)。结论:Sirt1蛋白在RHD大鼠心肌组织中表达上调,提示Sirt1可能参与RHD的发生。

Objective：To investigate the expression of Sirtl in cardiac tissues of rats with rheumatic heart disease （RHD）. Methods： The Lewis rats were randomly divided into 3 groups： acute RHD （ARHD） group, chronic RHD （CRHD） group and control group. The rats were infected with inactivated Streptococcus to establish ARHD model （7 weeks） and CRHD model （24 weeks）. The pathological changes of myocardium and mitral valves were observed by hematoxylin-eosin （HE） staining and Masson staining. The protein expression of Sirtl was detected by immunohistochemistry and western blotting. Results： Inflammatory infiltration in the myocardium and mitral valves was found in the ARHD group, and scattered inflammatory cell infiltration in myocardium and valve fibrosis were observed in the CRHD group. Compared with the control group, the protein expression level of Sirtl in the ARHD group and the CRHD group were significantly increased （ P 〈0.05 or P 〈0.01）, and the increase was more significant in the ARHD group （ P 〈0.01）. In addition, the expression of Sirtl protein in myocardial nucleus in the ARHD group and CRHD group showed an upward trend （ P 〈0.01）. Conclusion：Sirtl protein was up-regulated in RHD rats, suggesting that Sirtl might be involved in the occurrence of RHD.