Johnson R J, Floege J, Yoshimura A, Iida H, Couser W G, Alpers C E
Department of Medicine, University of Washington, Seattle.
J Am Soc Nephrol. 1992 Apr;2(10 Suppl):S190-7. doi: 10.1681/ASN.V210s190.
The glomerular mesangial cell may have several important beneficial functions in the normal glomerulus. These include the production of growth factors to allow normal cell turnover, the provision of structural support for the capillaries via the production of mesangial matrix, and the modulation of glomerular hemodynamics via their contractile properties. However, in various types of glomerular injury, the mesangial cell may acquire characteristics of a "myofibroblast", which may in fact be injurious to the glomerulus. These "activated" mesangial cells can be shown to be proliferating by one or more mechanisms that are mediated by platelets and that also involve the local production of platelet-derived growth factor. Like myofibroblasts in other tissues, the mesangial cell acquires smooth muscle cell-like properties, characterized by the de novo expression of alpha-smooth muscle actin, and by the development of fibroblast-like properties, characterized by the production of interstitial collagens in addition to normal mesangial matrix constituents. Identifying therapeutic strategies that prevent this phenotypic modulation of the mesangial cell may provide new ways to treat golmerular diseases.
肾小球系膜细胞在正常肾小球中可能具有几种重要的有益功能。这些功能包括产生生长因子以实现正常的细胞更新，通过产生系膜基质为毛细血管提供结构支持，以及通过其收缩特性调节肾小球血流动力学。然而，在各种类型的肾小球损伤中，系膜细胞可能获得“肌成纤维细胞”的特征，而这实际上可能对肾小球有害。这些“活化的”系膜细胞可通过由血小板介导的一种或多种机制增殖，这些机制还涉及局部产生血小板衍生生长因子。与其他组织中的肌成纤维细胞一样，系膜细胞获得平滑肌细胞样特性，其特征是α-平滑肌肌动蛋白的从头表达，以及成纤维细胞样特性的发展，其特征是除了正常的系膜基质成分外还产生间质胶原。确定预防系膜细胞这种表型调节的治疗策略可能为治疗肾小球疾病提供新方法。
