黄精多糖对糖尿病大鼠心肌纤维化影响

目的 观察黄精多糖(PSP)对糖尿病心肌病大鼠心肌纤维化影响,探讨其可能机制。方法 健康雄性SD大鼠,随机分为对照组、模型组、黄精多糖250、500、1000 mg/kg组,所有大鼠给予普通饲料,连续12周,观察各组大鼠一般情况,检测空腹血糖,血生化指标,血流动力学指标,计算心脏质量指数(HMI),左心室质量指数(LVMI),苏木素-伊红染色观察心肌形态学变化;Masson染色观察心肌胶原纤维分布;免疫组化法检测心肌组织骨形态发生蛋白-7(BMP-7)、转化生长因子β1(TGF-β1)、Smad2/3、Smad7蛋白表达。结果 与对照组比较,模型组大鼠空腹血糖[(24.81±2.30)mmol/L]、HMI[(4.16±1.14)]、LVMI[(2.85±0.09)]及LVEDP升高(P < 0.05);免疫组化结果显示,模型组大鼠心肌组织中TGF-β1、Smad2/3蛋白的表达显著增加(P < 0.05),BMP-7、Smad7蛋白表达明显减少(P < 0.05);HE、Masson染色显示模型组大鼠心肌组织病理损伤严重。与模型组比较,黄精多糖1 000 mg/kg组大鼠空腹血糖[(13.28±2.08)mmol/L]、HMI[(3.21±0.07)]、LVMI[(2.09±0.02)]及LVEDP下降(P < 0.05),心肌组织中TGF-β1、Smad2/3蛋白表达显著减少(P < 0.05),BMP-7 、Smad7蛋白表达明显升高(P < 0.05);心肌组织病理改变有所改善。结论 黄精多糖可改善糖尿病大鼠心肌纤维化,其机制可能与促进心肌组织中BMP-7表达,影响TGF-β1/Smads信号通路有关。

Effect of Polygonatum sibiricum polysaccharides on myocardial fibrosis in rats with diabetes

Objective To observe the effect of Polygonatum sibiricum polysaccharides(PSP) on myocardial fibrosis in diabetic cardiomyopathy rats and to explore its possible mechanism.Methods Healthy male Sprague-Dawkey rats were randomly divided into normal group,model group,and 250,500,1000 mg/kg PSP groups and all the rats were fed with normal diet for 12 consecutive weeks.General conditions of the rats in each group were observed;fasting blood glucose (FBG),blood biochemical indexes,hemodynamic indexes were detected and heart mass index (HMI),left ventricular mass index (LVMI),and left ventricular end-diastolic pressure (LVEDP)were determined.Hematoxylin-eosin staining was used to observe the changes of myocardial morphology;Masson staining was used to observe the distribution of collagen fiber;the expressions of the bone morphogenetic protein-7(BMP-7),transforming growth factor beta 1 (TGF-β1),Smad2/3 and Smad7 were detected with immunohistochemistry.Results Compared with those of the control group,the FBG (24.81±2.30 mmol/L),HMI (4.16±1.14),LVMI (2.85±0.09) and LVEDP of the rats in the model group were increased (all P < 0.05).Immunohistochemistry results showed that the expressions of TGF-β1 and Smad2/3 protein were significantly increased (P < 0.05);the expressions of BMP-7 and Smad7 protein were significantly reduced(P < 0.05);HE and Masson staining showed that the cardiac tissues were serious damaged for the rats in the model group.Compared with those of the model group,the FBG (13.28±2.08 mmol/L),HMI (3.21±0.07),LVMI (2.09±0.02),and LVEDP were decreased (all P < 0.05);the expressions of TGF-β1 and Smad2/3 protein were significantly reduced (both P < 0.05);the expressions of BMP-7 and Smad7 protein were significantly increased (both P < 0.05);and the pathological changes of cardiac tissue were improved for the rats in 1 000 mg/kg PSP treatment group.Conclusion PSP can improve myocardial fibrosis in diabetic rats and its mechanism may be related to the promoted expression of BMP-7 in cardiac tissue,which affects the TGF-β1 /Smads signal pathway.