Induction of metalloproteinases by glomerular mesangial cells stimulated by proteins of the extracellular matrix
Induction of metalloproteinases by glomerular mesangial cells stimulated by proteins of the extracellular matrix
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DOI：
10.1681/asn.v12188
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发表时间：
2001-01-01
影响因子：
13.6
通讯作者：
Steadman, R
中科院分区：
文献类型：
--
作者：
Martin, J;Eynstone, L;Steadman, R
人肾小球系膜细胞（HMC）包埋在系膜基质（MM）中，通过合成和降解之间的动态平衡来控制其周转。降解由基质金属蛋白酶（MMP）控制，其活性与肾小球疾病的进展有因果关系。在其他系统中，MMP分泌可能直接受到暴露于特定基质蛋白的影响。因此，本研究探讨了不同基质成分对HMC粘附及其分泌和激活明胶酶MMP 2和MMP 9的影响。HMC与IV型胶原和I型胶原的粘附力很强（用结晶紫染色定量）（P < 0.01，相对于与对照、牛血清白蛋白（BSA）包被的威尔斯孔的结合力），与明胶IV和纤连蛋白的粘附力较弱（P < 0.05）。与玻连蛋白和层粘连蛋白的结合与对照威尔斯孔无统计学差异。在将这些基质蛋白（0.1 μ g/ml至100 μ g/ml）添加至生长停滞的HMC 72小时后，条件培养基的酶谱确定只有纤连蛋白和胶原蛋白I和IV剂量依赖性地增加潜伏的（72 kD）MMP 2分泌和活化。然而，纤连蛋白也诱导MMP 9的分泌。从HMC已与纤连蛋白共培养72小时的膜制备，以调查是否MMP 2在该系统中的激活是由于膜型（MT）-MMP的作用。当与潜伏的MMP 2孵育长达24小时时，这些膜以时间和剂量依赖性的方式激活酶。结果表明，特定的基质成分增加了HMC分泌MMP 2和MMP 9。此外，MT-MMP活性，选择性诱导纤连蛋白，有牵连的激活分泌的蛋白酶。
Human glomerular mesangial cells (HMC) are embedded in the mesangial matrix (MM) and control its turnover through a dynamic equilibrium between synthesis and degradation. Degradation is controlled by matrix metalloproteinases (MMP), whose activity has been causally implicated in the progression of glomerular disease. In other systems, MMP secretion may be directly affected by exposure to specific matrix proteins. The present study, therefore, investigated the effect of different matrix components on the adherence of HMC and on their secretion and activation of the gelatinases MMP2 and MMP9. HMC adhered strongly (quantified using crystal violet staining) to collagen IV and collagen I (P < 0.01, relative to binding to control, bovine serum albumin (BSA)-coated wells) and to a lesser extent to gelatin IV and fibronectin (P < 0.05). Binding to vitronectin and laminin was not statistically different to control wells. After the addition of these matrix proteins (0.1 mug/ml to 100 mug/ml) to growth-arrested HMC for 72 h, zymography of the conditioned medium established that only fibronectin and collagens I and IV dose-dependently increased latent (72 kD) MMP2 secretion and activation. Fibronectin, however, also induced the secretion of MMP9. Membranes from HMC that had been cocultured with fibronectin for 72 h were prepared to investigate whether the activation of MMP2 in this system was due to the action of membrane-type (MT)-MMP. When incubated with latent MMP2 for times up to 24 h, these membranes activated the enzyme in a time- and dose-dependent manner. The results demonstrate that specific matrix components increased the secretion of MMP2 and MMP9 from HMC. In addition, MT-MMP activity, selectively induced by fibronectin, was implicated in the activation of the secreted proteinases.