S-myotrophin promotes the hypertrophy of myotube as insulin-like growth factor-I does
S-myotrophin promotes the hypertrophy of myotube as insulin-like growth factor-I does
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DOI：
10.1016/s1357-2725(01)00035-8
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发表时间：
2001-08-01
影响因子：
4
通讯作者：
Ito, T
中科院分区：
文献类型：
--
作者：
Hayashi, T;Ogawa, T;Ito, T
我们已经报道了一种新的肌肉细胞生长因子，它的结构是带有糖链的多肽，它是从猪骨骼肌中成功纯化出来的。它被命名为S-肌营养素。为探讨S肌营养素在骨骼肌生长中的作用，通过比较S肌营养素和胰岛素样生长因子-I(IGFI)对原代培养的鸡骨骼肌细胞(几乎全部由多核肌管组成)的作用。S-肌营养素和胰岛素样生长因子-I均能显著提高培养细胞的肌酸激酶活性，两种物质的反应相似。这些因子的加入也增加了细胞内蛋白质的含量。在分化培养液中，S-肌营养素处理组的肌球蛋白和肌动蛋白含量显著高于对照组(未刺激组)。经IGF-I处理的培养液中这些蛋白质的含量也高于对照组，但差异无统计学意义。免疫印迹分析证实，肌球蛋白和肌动蛋白在S-肌营养素刺激和胰岛素样生长因子-I刺激下显著增加。用抗结蛋白抗体染色的形态观察表明，S-肌营养素和胰岛素样生长因子-I处理的肌管的大小都明显大于对照肌管。这些结果表明，S-肌营养素是一种通过肌肉结构蛋白的积累而导致骨骼肌细胞肥大的强有力的介导物。(C)2001爱思唯尔科学有限公司。保留所有权利。
We have reported previously that a novel muscle cell growth factor, having a structure of a peptide with sugar chains, was successfully purified from porcine skeletal muscle. It was named s-myotrophin. To determine the role of s-myotrophin in skeletal muscle growth, the effect of s-myotrophin on primary cultured chick skeletal muscle cells (composed almost totally of multinucleated myotubes) was investigated by comparing s-myotrophin with Insulin-like growth factor-I (IGF-I). Both s-myotrophin and IGF-I significantly increased creatine kinase activity of the cultures; both substances gave similar responses. Intracellar protein content was also increased by the addition of these factors. The content of myosin and actin in s-myotrophin treated culture in the differentiation medium was significantly higher than that of the control (unstimulated). The content of those proteins in IGF-I treated culture was also higher than that of control, but the differences were not statistically significant. Immunoblot analysis confirmed that the amounts of myosin and actin in the myocytes were greatly increased by s-myotrophin stimulation and also by IGF-I stimulation. Morphological observations using an anti-desmin antibody staining procedure demonstrated that the size of both s-myotrophin and IGF-I treated myotubes was appreciably larger than that of control myotubes. These results suggest that s-myotrophin is a potent mediator of skeletal muscle cell hypertrophy thorough the accumulations of muscle structural proteins. (C) 2001 Elsevier Science Ltd. All rights reserved.