波生坦及依那普利对糖尿病肾病模型干预的对比研究

A comparison study between bosentan and enalapril treatment in diabetic nephropathy

目的应用波生坦或依那普利对糖尿病肾病(DN)模型进行干预,比较两药疗效,并探讨其作用机制。方法Wistar大鼠摘除右肾后,静脉注射链脲菌素成DN模型,然后分成模型组、波生坦组、依那普利组。对照组为仅注射缓冲液。每组大鼠6只。20周时测量体重、血压、血糖及24h尿蛋白定量,处死大鼠,用PAS染色及Masson染色观察肾脏病理变化;用RT-PCR及免疫组化方法检测肾组织中Ⅰ型胶原(ColⅠ)、Ⅳ型胶原(ColⅣ)、转化生长因子-β1(TGF-β1)、结缔组织生长因子(CTGF)及骨形成蛋白-7(BMP-7)的mRNA及蛋白质表达。结果与对照组相比,糖尿病模型组大鼠血糖、平均动脉压、尿蛋白定量及肾重/体重比值均显著上升(P<0.05或0.01);肾小球系膜及基膜相对面积及肾间质纤维组织相对面积均显著扩大(P<0.01);肾组织内ColⅠ、ColⅣ、TGF-β1及CTGF的mRNA及蛋白质表达均显著上调(P<0.05或0.01),而BMP-7mRNA及蛋白质表达则下调(P<0.05或0.01)。波生坦或依那普利干预后,上述上调指标除血糖外都被显著抑制(P<0.05或0.01),而抑制的BMP-7表达却被上调(P<0.01)。两种药物之间比较,作用无显著性差异(P>0.05)。结论波生坦或依那普利对DN模型的干预效果相似,此疗效可能与下调肾组织TGF-β1及CTGF表达、及上调BMP-7表达相关。

Objective To compare different effects of treatment with bosentan or enalapril in diabetic nephropathy, and investigate their pharmacological mechanisms. Methods Uninephrectomized Wistar rats were given intravenously streptozotocin(STZ). The diabetic rats were randomly divided the following:DN+veh group (only buffer by gavage),DN+bos group(bosentan 100 mg·kg-1·d-1 by gavage),DN+ena group (enalapril 10 mg·kg-1·d-1 by gavage).An additional set of uninephrectomized rats were given no STZ were used as control group (CTR). Each group consisted of 6 rats. By twenty weeks, the body weight, blood pressure,blood glucose and proteinuria level were measured in each rat. Then, the rats were sacrificed and the remnant kidney of each rat was harvested and weighed. The mRNA and the protein expression of collagenⅠ(ColⅠ),collagenⅣ(Col Ⅳ),transforming growth factor β1(TGF β1),connective tissue growth factor (CTGF),bone morphogenetic protein 7(BMP 7)in kidney tissue were semi quantitatively determined with reverse transcription polymerase chain reaction(RT PCR) and immunohistochemical staining respectively.Results Compared with CTR, the mean arterial pressure(MAP), serum glucose level, urinary protein excretion, and the ratio of kidney weight/body weight were significantly increased(P< 0 05 or 0 01), and the relative area of glomerular mesangium and basement membrane and the relative area of interstitial fibrosis were also significantly enlarged in the DN+veh group(P< 0 01). Compared with CTR, the expression of ColⅠ,Col Ⅳ,TGF β1 and CTGF mRNA and protein was significantly up regulated, but the expression of BMP 7 mRNA and protein was significantly down regulated in their kidney tissue of DN+veh group(P< 0 05 or 0 01). After intervention with bosentan or enalapril,the upregulation of the above mentioned parameters,except blood glucose,were all significantly inhibited(P< 0 05 or 0 01), but the down regulated BMP 7 expression was significantly enhanced(P< 0 01). There was no significant difference of intervention effects between bosentan and enalapril(P >0 05). Conclusions In this study, pharmacological effects of bosentan or enalapril on diabetic nephropathy rats are quite similar. These effects may result from the down regulation of TGF β1 and CTGF expression and up regulation of BMP 7 expression in kidney tissue.