目的：检测转化生长因子（TGF）-β、Smad信号通路蛋白和α-平滑肌肌动蛋白（α-SMA）在糖尿病肾病（DN）患者肾活检组织中的表达，探讨DN的发病机制。方法收集DN肾组织标本28例（DN组）；非DM行肾切除的正常肾组织10例为对照组。应用免疫组化方法检测TGF-β1、TGF-β受体（R）Ⅰ、TGF-βRⅡ、Smad2/3、α-SMA在肾组织中的表达。结果（1）TGF-β1、TGF-βRⅠ、TGF-βRⅡ、Smad2/3在DN组和对照组中均有表达，前者高于后者， DN组早期光镜下肾组织未见明显异常时即有明显的高表达，而随着疾病的进展未见表达增高的现象。肾小球、肾小管出现纤维化后并不表达上述因子。（2）对照组的α-SMA仅表达于肾血管、肾小球和肾小管，而肾间质未见α-SMA表达，而DN组α-SMA在上述组织中均有表达。结论 TGF-β及Smad信号转导通路参与了DN的发病，DN可能与免疫复合物性肾小球肾炎具有相似的发病机制。%Objective To investigate the mechanism of the pathogenesis of diabetic nephropathy (DN) by detecting the expressions of transforming growth factor (TGF)-β, Smad proteins andα-smooth muscle actin (α-SMA) in kidney biopsy of patients with diabetic nephropathy (DN). Methods Twenty-eight patients with DN who underwent renal biopsy were col-lected as DN group. Ten subjects without DN who underwent nephrectomy were taken as control group. The expressions of TGF-β1, TGF-βRⅠ,TGF-βRⅡ,Smad2/3 andα-SMA in renal tissues were detected by immunohistochemistry stain. Results (1)TGF-β1,TGF-β RⅠ,TGF-β RⅡ,and Smad2/3 were expressed in the glomeruli and tubules of both DN group and control group, while the expressions of TGF-βand Smad proteins were significantly higher in DN group than those in control group. At the early stage of DN, TGF-βand Smad proteins were significantly expressed even though there was no remarkable lesions observed by light microscopy. There was no correlation between increased expression and the progres-sion of DN. These proteins were not expressed after glomerulus and renal tubule fibrosis. (2) In control group,α-SMA was identified only in the vascular walls, glomerulus and renal tubules, while it was expressed in almost all parts of kidney in DN group. Conclusion TGF-β and Smad signals involved in the pathogenesis of DN, which may have similar pathogenesis with immune complex glomerulonephritis.
展开▼
