Yuan L-Q, Lu Y, Luo X-H, Xie H, Wu X-P, Liao E-Y
Institute of Metabolism and Endocrinology, The Second Xiang-Ya Hospital, Central South University, Changsha, Hunan, China.
Amino Acids. 2007;32(3):425-30. doi: 10.1007/s00726-006-0380-4. Epub 2006 Aug 29.
Taurine is found in bone tissue, but its function in skeletal tissue is not fully understood. The present study was undertaken to investigate regulation of gene expression of connective tissue growth factor (CTGF), and the roles of mitogen-activated protein kinases (MAPKs) in murine osteoblast MC3T3-E1 cells treated with taurine. Western blot analysis showed taurine stimulated CTGF protein secretion in a dose- and time-dependent manner. Taurine induced activation of extracellular signal-regulated kinase (ERK), but not p38 and c-jun N-terminal Kinase (JNK), in osteoblasts. Furthermore, pretreatment of osteoblasts with the ERK inhibitor PD98059 abolished the taurine-induced CTGF production. These data indicate that taurine induces CTGF secretion in MC3T3-E1 cells mediated by the ERK pathway, and suggest that osteoblasts are direct targets of taurine.
牛磺酸存在于骨组织中，但其在骨骼组织中的功能尚未完全明确。本研究旨在探讨牛磺酸处理的小鼠成骨细胞MC3T3-E1中结缔组织生长因子（CTGF）基因表达的调控以及丝裂原活化蛋白激酶（MAPKs）的作用。蛋白质免疫印迹分析表明，牛磺酸以剂量和时间依赖性方式刺激CTGF蛋白分泌。牛磺酸可诱导成骨细胞中细胞外信号调节激酶（ERK）的激活，但不诱导p38和c-jun氨基末端激酶（JNK）的激活。此外，用ERK抑制剂PD98059预处理成骨细胞可消除牛磺酸诱导的CTGF产生。这些数据表明，牛磺酸通过ERK途径诱导MC3T3-E1细胞中CTGF的分泌，并提示成骨细胞是牛磺酸的直接作用靶点。
