左归降糖益肾方对糖尿病肾病MKR鼠肾组织TGF-β1及CTGFmRNA表达的影响

Effect of Zuogui Jiangtang Yishen Decoction on mRNA Expressions of Renal TGF-β1 and CTGF of MKR Mice with Diabetic Nephropathy

摘要:

目的: 探讨左归降糖益肾方对糖尿病肾病骨骼肌特异性胰岛素样生长因子-1受体缺失转基因鼠(MKR鼠)转化生长因子-β₁(TGF-β₁)及结缔组织生长因子(CTGF)基因mRNA表达的影响. 方法: MKR鼠60只,按性别、空腹血糖、体重随机分为4组,即空白组,模型组,左归降糖益肾方组(28.8 g·kg^-1),阳性药物组(格列喹酮0.003 9 g·kg^-1与盐酸贝那普利0.001 3 g·kg^-1),每组15只,同龄C57鼠10只作为正常组,除正常组与空白组外,其余各组高脂喂养联合单侧肾切除造成糖尿病肾病(DN)小鼠模型,造模后8周 ig给予相应药物8周,留取尿标本,心脏采血处死各组小鼠.电化学法检测空腹血糖(FBG),常规生化法检测血清肌酐(SCr),尿素氮(BUN)含量, ELISA检测尿微量白蛋白含量;并取新鲜肾组织, RT-PCR检测肾组织TGF-β₁及CTGF mRNA的表达水平;其余组织4%多聚甲醛固定24 h,HE及Masson染色观察肾组织病理变化. 结果: 与空白组比较,模型组小鼠FBG,SCr,BUN及尿微量白蛋白含量明显升高(P <0.01);与模型比较,左归降糖益肾方能明显降低DN小鼠FBG,降低SCr,BUN及尿微量白蛋白含量(P <0.01);下调TGF-β₁ mRNA及CTGF mRNA的表达水平(P <0.05, P <0.01),疗效等同于阳性药物组;与空白组比较,模型组肾组织肾小球体积缩小,肾小球萎缩,球囊腔增宽,球囊腔壁层细胞增多且异形化,左归降糖益肾方能明显改善肾组织病理损伤. 结论: 左归降糖益肾方可以通过下调TGF-β₁ mRNA及CTGF mRNA的表达水平,从而抑制肾组织纤维化的发生发展.

Abstract:

Objective: To observe the effects of the Zuogui Jiangtang Yishen decoction (ZJYD) on the mRNA expressions of renal transforming growth factor-β₁ (TGF-β₁) and connective tissue growth factor (CTGF) of MKR mice with diabetic nephropathy. Method: Sixty MKR mice were divided into 4 groups, the control group, the model group, the ZJYD group (28.8 g·kg^-1) and the gliquidone (0.003 9 mg·kg^-1) combined benazepril hydrochloride (0.001 3 g·kg^-1) group of 15 each according to sex, fasting blood-glucose (FBG) and body weight. Another 15 C57 mice with the same age were assigned to the normal group. The diabetic nephropathy model was induced in mice by mono-nephrectomy and a high-fat diet. Eight weeks after the operation, the drugs were intragastrically administrated to the mice for eight weeks. The levels of FBG were detected by electrochemical method. Serum creatinine (SCr) and urea nitrogen (BUN) were observed by routine biochemistry quantitative assay. The urine microalbminurine (UmALB) was observed by using ELISA. The mRNA expressions of TGF-β₁ and CTGF were analyzed by using RT-PCR. The pathological changes in the renal tissues were observed by HE staining and Masson staining. Result: Compared to the control group, the FBS, SCr, BUN and UmALB increased in the model group (P <0.01). Compared to the model group, the FBS, SCr, BUN and UmALB decreased, the mRNA expressions of TGF-β₁ and CTGF decreased in the ZJYD group (P <0.01). Moreover, the pathological lesion of renal tissue was improved in the ZJYD group. The curative effects of ZJYD were equivalent to the gliquidone combined benazepril hydrochloridegroup. Conclusion: ZJYD could inhibit the development of renal interstitial fibrosis by down-regulating the mRNA expressions of TGF-β₁ and CTGF.