Kanoh M, Wiggins R C, Konat G
Department of Anatomy, West Virginia University School of Medicine, Morgantown 26505.
Metab Brain Dis. 1992 Sep;7(3):147-56. doi: 10.1007/BF01000160.
The effect of factors released from N2A neuroblastoma cells on the expression of myelin protein genes in glioma C6 cells, i.e., proteolipid protein (PLP) and myelin-associated glycoprotein (MAG), was studied. Both cells lines were propagated in serum-free DMEM-F10 (1:1) medium. The addition of 50% N2A conditioned medium (N2ACM) stimulated the proliferation of C6 cells by approximately 4.5 fold as compared to control cells. The N2ACM-treated cells formed aggregates indicating increased cell-cell affinity. The exposure of C6 cells to N2ACM transiently stimulated the expression of both the MAG-specific and the PLP-specific messages up to eight and four fold over the control values, respectively. The maximal upregulation of the PLP gene occurred two days after N2ACM administration and preceded that of the MAG gene by two days. The effect of N2ACM was dose-dependent in the range of 12.5 to 50%. The secretion of N2A paracrine factors that stimulated the myelin gene expression was also time-dependent. The optimal conditioning time for the release of the PLP gene-stimulating activity was one day, while the maximal MAG gene-stimulating activity was found in the medium conditioned for 3 days. This cellular system may provide a convenient model for studies on trophic neuronal-glial interaction. Furthermore, the results indicate a difference in the regulatory mechanisms between the PLP and the MAG genes.
研究了N2A神经母细胞瘤细胞释放的因子对胶质瘤C6细胞中髓磷脂蛋白基因，即蛋白脂蛋白（PLP）和髓磷脂相关糖蛋白（MAG）表达的影响。两种细胞系均在无血清DMEM-F10（1:1）培养基中培养。与对照细胞相比，添加50%的N2A条件培养基（N2ACM）可使C6细胞的增殖刺激约4.5倍。经N2ACM处理的细胞形成聚集体，表明细胞间亲和力增加。将C6细胞暴露于N2ACM可短暂刺激MAG特异性和PLP特异性信息的表达，分别比对照值高出8倍和4倍。PLP基因的最大上调发生在给予N2ACM两天后，比MAG基因早两天。N2ACM的作用在12.5%至50%的范围内呈剂量依赖性。刺激髓磷脂基因表达的N2A旁分泌因子的分泌也具有时间依赖性。释放刺激PLP基因活性的最佳条件培养时间为一天，而在条件培养3天的培养基中发现最大的MAG基因刺激活性。该细胞系统可为研究营养性神经元-胶质细胞相互作用提供一个方便的模型。此外，结果表明PLP基因和MAG基因之间的调控机制存在差异。
