TGF-β/Smads信号通路参与苦参素抑制糖尿病心肌病大鼠心肌纤维化及改善心功能作用

TGF-β/ Smads signal pathway is involved in the anti-fibrotic effect of matrine and improvement of the cardiac function in the diabetic cardiomyopathy rats

目的观察TGF-β/Smads信号通路是否参与苦参素抑制糖尿病心肌病大鼠心肌纤维化及改善心功能作用。方法采用链脲佐菌素单次腹腔注射法制作糖尿病心肌病大鼠模型,苦参素灌胃法对其进行干预。分别建立对照组(Ctrl)、苦参素组(Mat)、糖尿病心肌病组(Db CM)和糖尿病心肌病+苦参素组(Db CM+Mat)。对照组仅予以单次腹腔注射生理盐水,苦参组先予以单次腹腔内注射生理盐水,随后应用苦参素溶液灌胃;糖尿病心肌病组仅予以单次腹腔注射链脲佐菌素,糖尿病心肌病+苦参素组先予以单次腹腔注射链脲佐菌素,随后应用苦参素溶液灌胃。应用心脏血流动力学检查每组大鼠左室收缩压力(left ventricular systolic pressure,LVSP)及左室舒张末压力(left ventricular end-diastolic pressure,LVEDP)以评估心脏功能;采用免疫荧光染色法评估心肌纤维化程度;采用蛋白免疫印迹法检测转化生长因子-β1(transforming growth factor beta-1,TGF-β1)、磷酸化的Smad2和Smad3蛋白水平以评估TGF-β1/Smads信号通路的活化。结果与对照组相比,糖尿病心肌病组大鼠心脏LVSP显著下降(P<0.05),LVEDP显著升高(P<0.05);Ⅰ型胶原表达显著增加(P<0.05);TGF-β1(P<0.05)及P-Smad2/3(P<0.05)蛋白水平表达均显著上调。与糖尿病心肌病组相比,糖尿病心肌病+苦参素组大鼠LVSP显著升高(P<0.05),LVEDP显著下降(P<0.05);Ⅰ型胶原表达显著减少(P<0.05);TGF-β1及P-Smad2/3蛋白水平表达均显著下调(P<0.05)。结论 TGF-β/Smads信号通路参与苦参素抑制糖尿病心肌病大鼠心肌纤维化及改善心功能作用。

Objective To explore whether the TGF-β / Smads signal pathway is involved in the effect of matrine on cardiac fibrosis and cardiac function in diabetic cardiomyopathy rats. Methods The rats were divided into control group,matrine group,diabetic cardiomyopathy group and diabetic cardiomyopathy ＋ matrine group. The rats were given saline by single intraperitoneal injection in control group,and based on this,the rats were additionally given matrine by gavage in matrine group. The rats were treated with streptozotocin（ STZ） by single intraperitoneal injection in diabetic cardiomyopathy group,and based on this,the rats were additionally given matrine by gavage in diabetic cardiomyopathy ＋ matrine group. The left ventricular systolic pressure（ LVSP） and left ventricular end-diastolic pressure（ LVEDP） were measured to evaluate the cardiac function. The cardiac fibrosis was evaluated by immunofluorescence staining.The protein expression of transforming growth factor beta-1（ TGF-β1）,the phosphorylated Smad2 and Smad3 were detected by Western blot to evaluate the activation of TGF-β1/ Smads signal pathway. Results Compared to control group,LVSP decreased in diabetic cardiomyopathy（ Db CM） group（ P 0. 05）,LVEDP and collagen-Ⅰ expression increased significantly（ P 0. 05）,and the expression of TGF-β1and P-Smad2 /3 protein were significantly up-regulated（ P 0. 05）. Compared to Db CM group,LVSP increased in Db CM ＋ matrine group（ P 0. 05）,LVEDP and collagen-Ⅰ expression significantly decreased（ P 0. 05）,the expression of TGF-β1and PSmad2 /3 proteins was significantly down-regulated（ P 0. 05）. Conclusion TGF-β / Smads signal pathway is involved in the anti-fibrotic effect of matrine and the improvement of cardiac function in the diabetic cardiomyopathy rats.