Roncari D A, Thompson C E
Institute of Medical Science, University of Toronto, Ont., Canada.
Biochem Cell Biol. 1990 Apr;68(4):764-8. doi: 10.1139/o90-110.
A protein released into the culture medium by omental preadipocytes of massively obese persons, which stimulates the replication of rat perirenal preadipocytes, has been purified to a high degree. By gel filtration chromatography, the molecular mass of the mitogenic protein was approximately 66,000 daltons (Da), while on sodium dodecyl sulfate - polyacrylamide gel electrophoresis, two subunits were obtained, relative masses (Mr) of approximately 31,000 and approximately 35,000. The isoelectric point of the approximately 66,000 Da entity was 5.6 +/- 0.2. By specific radioreceptor assay, the purified protein was related to epidermal growth factor and transforming growth factor alpha. It was not related to insulin-like growth factors I and II by radioimmunoassay and radioreceptor assay. We propose that the approximately 66,000 Mr protein, and other mitogenic proteins released by preadipocytes from massively obese persons, act through paracrine-autocrine mechanisms and may play a role in the development of the hyperplasia of enlarged fat cells characteristic of massive corpulence.
一种由极度肥胖者网膜前脂肪细胞释放到培养基中的蛋白质，它能刺激大鼠肾周前脂肪细胞的复制，现已被高度纯化。通过凝胶过滤色谱法，有丝分裂原性蛋白的分子量约为66,000道尔顿（Da），而在十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳中，得到了两个亚基，相对分子质量（Mr）分别约为31,000和约35,000。约66,000 Da实体的等电点为5.6±0.2。通过特异性放射受体测定，纯化后的蛋白质与表皮生长因子和转化生长因子α相关。通过放射免疫测定和放射受体测定，它与胰岛素样生长因子I和II无关。我们提出，约66,000 Mr的蛋白质以及极度肥胖者前脂肪细胞释放的其他有丝分裂原性蛋白，通过旁分泌 - 自分泌机制发挥作用，可能在极度肥胖所特有的脂肪细胞增生的发展过程中起作用。
