Regulation of insulin-like growth factor-binding protein-5 expression during Schwann cell differentiation
Regulation of insulin-like growth factor-binding protein-5 expression during Schwann cell differentiation
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DOI：
10.1210/en.140.10.4478
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发表时间：
1999-10-01
期刊：
影响因子：
4.8
通讯作者：
Feldman, EL
中科院分区：
文献类型：
--
作者：
Cheng, HL;Shy, M;Feldman, EL
我们已经报道，永生化雪旺细胞（SC）表达胰岛素样生长因子I受体和胰岛素样生长因子结合蛋白-5（IGFBP-5）。IGF-I促进SC存活并保护SC条件培养基中的IGFBP-5免受蛋白水解。在本研究中，我们检测了IGF-I和IGFBP-5在原发性SC中的作用。IGF-I增强原发性SC分化以及IGFBP-5和髓鞘形成蛋白P-o的基因和蛋白表达。稳定过表达人IGFBP-5的SC也具有更高水平的P-o基因表达。磷脂酰肌醇-3激酶抑制剂（LY 294002），而不是丝裂原活化蛋白激酶激酶抑制剂（PD 98059），阻断IGF-I增强IGFBP-5基因和蛋白表达。总的来说，这些结果表明，IGF-I促进SC分化，这可能部分通过增强IGFBP-5表达通过磷脂酰肌醇-3激酶激活。这些数据支持IGFBP-5表达增强与细胞分化之间的联系。
We have reported that immortalized Schwann cells (SC) express the insulin-like growth factor I receptor and IGF-binding protein-5 (IGFBP-5). IGF-I promotes SC survival and protects IGFBP-5 in SC-conditioned medium from proteolysis. In the current study we examined the roles of IGF-I and IGFBP-5 in primary SC. IGF-I enhances primary SC differentiation and gene and protein expression of IGFBP-5 and the myelinating protein, P-o. SC that stably overexpress human IGFBP-5 also have higher levels of P-o gene expression. The phosphatidylinositol-3 kinase inhibitor (LY294002), but not the mitogen-activated protein kinase kinase inhibitor (PD98059), blocks IGF-I enhancement of IGFBP-5 gene and protein expression. Collectively, these results suggest that IGF-I promotes SC differentiation, and this may occur in part by enhancing IGFBP-5 expression via phosphatidylinositol-3 kinase activation. These data support a link between enhanced IGFBP-5 expression and cellular differentiation.