Basic Study on the Utilization of Muscle Proteins Isolated from Cultured Skeletal Satellite Cells

研究了油牛成纤维细胞生长因子对骨骼肌卫星细胞增殖的影响。采用硫酸铵分级沉淀、CM-Sephadex C-50、Sephadex G-75和第二CM-Sephadex C-50层析的方法，从牛脑组织中分离纯化脑成纤维细胞生长因子。第二CM-Sephadex C-50柱在0.35-0.4M的氯化钠溶液中洗脱的部分具有刺激Balb/c3T3细胞DNA合成的活性。经SDS-聚丙烯酰胺凝胶电泳法分析，该蛋白主要由12000个分子量的脱多肽组成。综合数据(分子量和生物活性)表明，用这种方法分离的组分含有Gospodarowicz等人(1978)纯化的大量脑成纤维细胞生长因子。培养成年大鼠骨骼肌卫星细胞，用分离的脑成纤维细胞进行体外处理。形态观察和定量数据表明，脑成纤维细胞生长因子增加了细胞核的数量。新的细胞核似乎是卫星细胞增殖和部分卫星细胞融合的结果。但是，部分新细胞核来源于培养物中污染的成纤维细胞的生长。在150~250 ng/ml范围内，当卫星细胞被诱导分化时，该因子促进了细胞的增殖和随后的肌管形成。然而，卫星细胞的生物活性比我们想象的要低得多。这可能是由于成纤维细胞生长因子制剂中存在的杂质所致。

An investigation was undertaken to the effect oil bovine fibroblast growth factor on skeletal muscle satellite cell proliferation.1. We have examined to purify brain fibroblast growth factor (Brain FGF) from bovine brain tissue using this procedure involving ammonium sulfate fractionation, followed by chromatography on CM-Sephadex C-50, Sephadex G-75 and second CM-Sephadex C-50. The fraction eluting from second CM-Sephadex C-50 column at 0.35-0.4M NaCl was active in stimulating DNA synthesis in Balb/c3T3 cells. It mainly consisted of apolypeptide of 12,000 molecular weight when analyzed by SDS polyacryl-amide gel electrophoresis. The combined data ( molecular weight and biological activity ) suggested that the fraction isolated using this procedure contained a large quantity of brain FGF purified by Gospodarowicz et al.(1978).2. Skeletal muscle satellite cells were cultured from mature rats and were treated in vitro with the isolated brain FGF. Morphological observations and quantitative data indicated that the brain FGF increased the number of nuclei. The new nuclei seemed to result from satellite cell proliferation and from the fusion of some of them. But, a part of new nuclei originated from growth of fibroblast contaminated in cultures. In the range of 15 0-250 ng/ml , this factor promoted the level of proliferation and subsequent myotube formation when satellite cells were induced to differentiate. However, the biological activity for satellite cells was fairly lower than we had imagined. This may be due to impurities present in the FGF preparation.