白藜芦醇对糖尿病大鼠血管平滑肌细胞凋亡的影响及其机制研究

摘要

目的:探索白藜芦醇对糖尿病大鼠血管平滑肌细胞凋亡的影响及其调控机制.方法:实时定量PCR ( qRT-PCR)检测血清中单核细胞趋化蛋白-1 (MCP1)、巨噬细胞移动抑制因子(MIF)和白细胞介素18(IL-18)的mRNA水平;HE染色和Masson染色评价心肌纤维化水平;流式细胞术分析细胞凋亡;蛋白印迹检测Cleaved caspase-3、Cleaved caspase-9、B淋巴瘤2蛋白(Bcl-2)、Bcl-2相关蛋白X(Bax)、PI3K、p-PI3K、AKT、p-AKT蛋白表达.结果:白藜芦醇可降低STZ诱导的糖尿病大鼠血清MCP-1、MIF和IL-18的mRNA水平并改善心肌纤维化加剧. STZ诱导糖尿病组血管平滑肌细胞凋亡率明显高于对照组(P＜0. 05).与STZ诱导糖尿病组相比,STZ+白藜芦醇组血管平滑肌细胞凋亡率明显降低 (P＜0. 05).而且,白藜芦醇可抑制STZ诱导的糖尿病大鼠血管平滑肌细胞Cleaved caspase-3、Cleaved caspase-9和Bax蛋白表达,提高Bcl-2表达(P＜0. 05).与对照组相比,STZ诱导糖尿病组血管平滑肌细胞中p-PI3K/PI3K和p-AKT/AKT比率明显降低(P＜0. 05). STZ+白藜芦醇组血管平滑肌细胞p-PI3K/PI3K和p-AKT/AKT比率明显高于STZ诱导糖尿病组(P＜0. 05).结论:白藜芦醇可通过激活PI3K/AKT信号通路抑制STZ诱导的糖尿病大鼠血管平滑肌细胞凋亡.%Objective:To explore effects and mechanism of resveratrol on apoptosis of vascular smooth muscle cell in diabetic rats. Methods: The mRNA level of monocyte chemoattractant protein 1 (MCP1),macrophage migration inhibitory factor (MIF) and in-terleukin 18 (IL-18) was detected by quantitative real-time reverse transcription PCR (qRT-PCR). Myocardial fibrosis was analyzed by hematoxylin-eosin (HE) staining and Masson staining. Apoptosis was tested by flow cytometry. The expression of Cleaved caspase-3, Cleaved caspase-9,B cell lymphoma 2 (Bcl-2),Bcl-2-associated X protein (Bax),PI3K,p-PI3K,AKT and p-AKT was measured by Western blot. Results: The mRNA levels of MCP1,MIF and IL-18 in STZ-induced diabetic were reduced by resveratrol (P＜0. 05). The aggravation of myocardial fibrosis in STZ-induced diabetic rats was ameliorated by resveratrol. Apoptosis of vascular smooth muscle cell in STZ-induced diabetic rat group was higher than control group (P＜0. 05 ) . Compared with STZ-induced diabetic rat group, apoptosis of vascular smooth muscle cell in STZ+ resveratrol group was decreased (P＜0. 05). What′s more,the expression of Cleaved caspase-3,Cleaved caspase-9 and Bax in STZ-induced diabetic rats were inhibited by resveratrol(P＜0. 05). And the expression of Bcl-2 in STZ-induced diabetic rats was elevated by resveratrol(P＜0. 05). Compared with control group,the rate of p-PI3K/PI3K and p-AKT/AKT in STZ-induced diabetic rat group was decreased (P＜0. 05). The rate of p-PI3K/PI3K and p-AKT/AKT in STZ+ resveratrol group was higher than STZ-induced diabetic rat group ( P＜0. 05). Conclusion: Resveratrol represses apoptosis of vascular smooth muscle cell in STZ-induced diabetic rats through activating of PI3K/AKT signal pathway.