瓜蒌薤白半夏汤对心肌纤维化中整合素β1的抑制作用

Mechanism of Gualou Xiebai Banxia Decoction reversal myocardial fibrosis through integrin β1

目的研究整合素β1和纤维连接蛋白在血管紧张素Ⅱ(AngⅡ)诱导心肌纤维化中的作用,探讨瓜蒌薤白半夏汤(GXB)抗心肌纤维化的作用机制。方法 采用胰酶消化法培养乳鼠心肌成纤维细胞,建立AngⅡ诱导心肌纤维化模型。实验分为空白对照组,AngⅡ组,5%、10%、15%GXB含药血清组和缬沙坦含药血清组。空白对照组心肌成纤维细胞以空白对照组大鼠血清温育,其余各组均以AngⅡ1×10-6mmol/L刺激24h后,再分别以空白对照组大鼠血清、5%GXB含药血清、10%GXB含药血清、15%GXB含药血清、缬沙坦含药血清温育24h。RT-PCR法检测GXB对整合素β1mRNA表达水平的影响;ELISA检测培养上清液中纤维连接蛋白的量;MTT法检测心肌成纤维细胞增殖。结果与空白对照组比较,AngⅡ1×10-6mmol/L作用心肌成纤维细胞24h,整合素β1mRNA表达水平及纤维连接蛋白的量明显上调(P<0.01),心肌成纤维细胞增殖指数明显升高(P<0.01);经GXB含药血清干预后,与AngⅡ组比较,整合素β1mRNA的表达水平明显下降(P<0.01),纤维连接蛋白的量减少(P<0.05),心肌成纤维细胞增殖指数明显降低(P<0.01)。结论瓜蒌薤白半夏汤能够抑制AngⅡ诱导心肌纤维化,其作用机制可能与下调纤维连接蛋白/整合素β1表达有关。

Objective To investigate the effects of integrin β1 and fibronectin on cardiac fibroblasts induced by Angiotensin Ⅱ （Ang Ⅱ ）, and to expore the mechanism of Gualou Xiebai Banxia Decoction （GXB）, a compound traditional Chinese herbal medicine, in reversing myocardial fibrosis. Methods Fibroblasts derived from neonatal rats were cultured with enzymatic dissociation, and myocardial fibrosis was induced by Ang Ⅱ. The fibroblasts were divided into normal control group, AngⅡ group, 5% GXB-containing serum group, 10% GXB-containing serum group, 15% GXB-containing serum group, and Valsartan-containing group. Fibroblasts in normal control group were incubated by normal serum. In other experimental groups, fibroblasts were induced for 24 hours by AngⅡ （ 1 ×10^-6 mmol/L）, then incubated by 5% GXB-containing serum, 10% GXB-containing serum, 15% GXB- containing serum, and Valsartan-containing serum for 24 hours respectively. Integrin β1 mRNA expression was detected by RT-PCR, fibronectin content in the extracellular matrix were measured by ELISA, and proliferation of cardiac fibroblasts was measured by MTT. Results After 24-hour stimulation of Ang Ⅱ infibroblasts, compared with those in normal control group, the expression of integrin β1 mRNA raised significantly （P〈0.01）, fibronectin increased significantly （P〈0.05）. The model of myocardial fibrosis was intervented by different dosages of Gualou Xiebai Decoction. Compared with Ang Ⅱ group, the integrin β1 mRNA expression showed a significant downward trend（P〈 0.01 ）and fibronectin decreased（P〈 0.05 ）. Conclusion Gualou Xiebai Decoction can inhibit cardiac fibroblast induced by AngiotensinⅡ, and the mechanism may be related to fibronectin/integrin β1.