IgA肾病肾血管纤溶酶原激活物抑制物-1和基质金属蛋白酶-9的表达及其意义

EXPRESSIONS OF ALPHA-SMA, PAI-1, MMP-9 AND TIMP-1 IN RENAL VESSELS OF PATIENTS WITH IGA NEPHROPATHY

为探讨免疫球蛋白A肾病(IgA肾病)患者肾血管壁纤溶酶原激活物抑制物1(PAI1)、基质金属蛋白酶9(MMP9)、金属蛋白酶组织抑制物1(TIMP1)和α平滑肌肌动蛋白(αSMA)的表达及意义,采用免疫组织化学技术检测38例IgA肾病肾组织血管壁的PAI1、MMP9、αSMA和TIMP1的蛋白表达。结果显示,αSMA主要表达于平滑肌细胞;PAI1表达与αSMA类似;MMP9在平滑肌细胞和内皮细胞均表达;TIMP1仅在血管壁内膜的内皮细胞微弱表达。在IgA肾病LeeⅣ～Ⅴ级组,肾血管壁的PAI1、MMP9和αSMA表达显著高于LeeⅠ～Ⅲ级组(P<001)。直线相关分析显示,肾血管的PAI1、MMP9和αSMA表达与肾小管间质的纤维化和炎细胞浸润呈正相关(P<001)。提示PAI1可能参与介导了IgA肾病肾血管壁细胞外基质的积聚过程,MMP9则可能促进血管的平滑肌细胞迁移和内膜增生。

To explore expressions of α smooth muscle actin (α SMA), plasminogen activator inhibitor 1 (PAI 1), matrix metalloproteinase 9 (MMP 9)and tissue type inhibitor of metalloproteinase 1 (TIMP 1) in renal vessels of 38 patients with immunoglobulin A nephropathy (IgAN), immunohistochemistry method was used to detect abundances of the above proteins. The results showed that α SMA staining was found mainly in vascular smooth muscle cells (SMCs); apparent PAI 1 staining was also shown by vascular SMCs; MMP 9 expressed considerably in vascular both SMCs and endothelial cells; TIMP 1 was located only in vascular endothelial cells. In renal tissues of IgAN patients at Lee IV V grade, vascular expressions of α SMA?PAI 1 and MMP 9 were significantly higher than those at Lee I III grade ( P <0 01). Linear correlation analysis showed that vascular expressions of α SMA?PAI 1 and MMP 9 were associated with tubulointerstitial fibrosis and inflammatory infiltration ( P <0 01), indicating that PAI 1 may be involved in the process of ECM accumulation in renal vessels of IgAN patients, while MMP 9 may play a role in promoting vascular SMCs migration and neointimal formation.