O'Keefe R J, Puzas J E, Brand J S, Rosier R N
Department of Orthopaedics, University of Rochester, New York 14642.
Endocrinology. 1988 Jun;122(6):2953-61. doi: 10.1210/endo-122-6-2953.
Transforming growth factor-beta (TGF beta) is a local regulator of cell metabolism and growth. TGF beta increases the synthesis of collagen and enhances the deposition of matrix by almost all cells studied to date. The presence of TGF beta in cartilage suggests an important autocrine function, and the present study was designed to examine its influence on the matrix synthesis of chick epiphyseal chondrocytes. Chondrocytes were plated in serum-free (BSA-supplemented) medium or medium containing 10% fetal bovine serum (FBS), and after 24 h in monolayer culture were treated with TGF beta in identical medium. A 24-h incubation with TGF beta caused a dose-dependent decrease in collagen synthesis (-14%) and increase in noncollagen protein synthesis (+25%), with greater effects in serum-containing medium (-22% and +58%, respectively). Similarly, the stimulation of sulfate incorporation by TGF beta was greater in FBS-containing medium (+140%) than in serum-free medium (+70%). These changes were present by 6 h, were maximal in the 0.3-3.0 ng/ml dose range, and were found to reflect an alteration in extracellular protein synthesis. The enhancement of TGF beta effects by serum was abolished when chondrocytes were plated and exposed to TGF beta in medium containing dialyzed FBS (12-14K membrane). The present study indicates that TGF beta influences the synthesis of matrix components by growth plate chondrocytes. The effects are enhanced by factors present in serum.
转化生长因子-β（TGF-β）是细胞代谢和生长的局部调节因子。TGF-β可增加胶原蛋白的合成，并增强几乎所有迄今所研究细胞的基质沉积。软骨中TGF-β的存在提示其具有重要的自分泌功能，本研究旨在检测其对鸡骨骺软骨细胞基质合成的影响。将软骨细胞接种于无血清（添加牛血清白蛋白）培养基或含10%胎牛血清（FBS）的培养基中，单层培养24小时后，在相同培养基中用TGF-β处理。与TGF-β孵育24小时导致胶原蛋白合成呈剂量依赖性减少（-14%），非胶原蛋白合成增加（+25%），在含血清培养基中的作用更大（分别为-22%和+58%）。同样，TGF-β对硫酸盐掺入的刺激在含FBS的培养基中（+140%）比在无血清培养基中（+70%）更大。这些变化在6小时时出现，在0.3 - 3.0 ng/ml剂量范围内最大，且发现反映了细胞外蛋白质合成的改变。当软骨细胞接种并在含透析FBS（12 - 14K膜）的培养基中暴露于TGF-β时，血清对TGF-β作用的增强作用被消除。本研究表明，TGF-β影响生长板软骨细胞的基质成分合成。血清中的因子可增强这些作用。
