转化生长因子β_1和波形蛋白及结蛋白在糖尿病大鼠肾皮质中早期表达的研究

Early expression of TGF-β_1,vimentin and desmin genes in renal cortex of diabetic rats

目的 :探讨糖尿病大鼠早期不同阶段转化生长因子β1(TGF-β1)和波形蛋白 (vimentin)、结蛋白 (desmin)在大鼠肾皮质中表达的变化规律及其相互关系。方法 :建立 STZ诱导的 SD大鼠糖尿病模型 ;用 RT- PCR法半定量检测早期各观察时点糖尿病大鼠肾皮质中 TGF-β1和 vimentin、desmin m RNA的表达水平。结果 :1随着糖尿病病情的进展 ,TGF- β1和 vimentin m RNA的表达量分别从模型建立后第 7d和第 14 d起逐渐增多 (P=0 .0 0 1) ,desmin m RNA表达从第 14 d起却逐渐减少 (P<0 .0 5 )。 2糖尿病组的 TGF- β1与 vimentin的 m RNA表达呈正相关 (r=0 .74 0 ,P=0 .0 0 0 ) ,desmin与 TGF- β1的 m RNA表达呈负相关 (r=- 0 .6 95 ,P=0 .0 0 0 ) ,desmin与 vimentin的 m RNA表达也呈负相关 (r=- 0 .5 91,P=0 .0 0 2 )。结论 :糖尿病大鼠早期肾皮质中 TGF- β1和 vimentin的表达逐渐增多 ,desmin的表达却逐渐减少 ,提示 TGF- β1可能促进小管上皮细胞向成纤维细胞转化。

Objective: To study the expression of TGF-β_1,vimentin and desmin in the renal cortex of diabetic rats induced by STZ. Methods: Diabetes was induced in 24 male SD rats by single intraperitoneal injection of 1.0%STZ (70 mg/kg). Twenty-four age, weight and sex matched SD rats were used as controls. The expression of TGF-β_1,vimentin and desmin mRNA in the renal cortex were detected by RT-PCR on the 3rd,the 7th,the 14th and the 30th day after the DM rat model established . Results: ① The expression of TGF-β_1,vimentin mRNA in the renal cortex of diabetic rats gradually increased respectively from the 7th day and the 14th day after the model established ,and the expressive intensity was significantly greater than that in controls (P<0.05 or P<0.01). However,the expression of desmin mRNA in the renal cortex of diabetic rats gradually decreased from the 14th day after the model established ,and the expressive intensity was significantly less than that in controls (P<0.05 or P< 0.01 ). ② The expression of TGF-β_1 mRNA correlated positively to that of vimentin mRNA (r=0.740,P=0.000),while the expression of desmin mRNA correlated negatively to that of TGF-β_1 mRNA (r=-0.695,P=0.000) and to that of vimentin mRNA (r=-0.591,P=0.002). Conclusion: The expression of renal cortical TGF-β_1 and vimentin mRNA gradually increase while the expression of desmin mRNA gradually decrease during the first month of the diabetic model established suggest TGF-β_1 may play a role in the transformation of renal tubular epithelial cells into fibroblast during the progressive interstitial fibrosis of diabetic nephropathy.