摘要
目的研究在中国人家族性阿尔茨海默病(FAD)两个家系中发现的早老素-1(PS1)基因 V97L 和 A136G 突变对神经母细胞瘤 SH-SY5Y 细胞的影响及胰岛素样生长因子-1(IGF-1)的保护作用机制。方法建立稳定表达野生型和突变型 PS1基因的 SH-SY5Y 细胞模型,给予血清剥夺或血清剥夺加 IGF-1,比较各转染细胞株的凋亡易感性和 IGF-1的保护作用;同时检测各组细胞的葡萄糖掺入率和细胞膜上葡萄糖转运子-1(GLUT1)表达的变化。结果 V97L 和 A136G 突变细胞株对血清剥夺的敏感性增加,细胞凋亡率显著高于野生型细胞株和空载体转染细胞(MOCK)(P<0.01);IGF-1可以有效改善血清剥夺对 SH-SY5Y 细胞的影响,使凋亡细胞减少。各组细胞的葡萄糖掺入率无明显差别,但加入 IGF-1后各组葡萄糖掺入率平均增加25%,细胞膜 GLUT1的易位表达增加15%～20%。结论 PS1 V97L 和 A136G 突变使 SH-SY5Y 细胞对营养剥夺的易感性增加可能是 FAD神经元变性脱失的原因之一;IGF-1可通过促使葡萄糖转运,提高细胞活性,起到保护作用。
Objective To study the effects of two novel presenilin-1 （PSI） mutations, V97L and A136G, discovered in 2 families of Alzhaimer＇s disease （AD） in China, on human neuroblastoma cells and the protective role of insulin-like growth factor-1 （ IGF-1 ）. Methods Two mutation type （MT） PS-1 genes with the mutational sites V97L and A136G were established. These 2 MT genes, wild type （WT） PS-1 gene, and mock were stably tansfected into the human neuroblastoma cells of the line SH-SYSY. The 4 kinds of transfected cells were divided into 3 subgroups： （ 1 ） control subgroup, cultured in normal medium with serum, （2） serum deprivation subgroup, cultured in the medium without serum, and （3） serum deprivation ＋ IGF-1 subgroup, cultured in serum deprivation medium plus IGF-1. Twenty-four hours later MTT colorimetry was used to calculate the cell survival rate. Hoechst33258 method and phophatidylinositol/ annexin V-FITC double staining flow cytometry were used to observe the cell apoptosis. The glucose uptake was measured. Western blotting was used to analyze the protein expression of glucose transporter protein （ GLUT）-1 in the cell membrane. Results Different tests all showed that the cell survival rates of the V97L and A136G serum deprivation subgroups were both significantly lower than those of the corresponding WT and Mock subgroups （ P 〈 0.01, P 〈 0.05 ）, the cell survival rates of the all serum deprivation ＋ IGF-1 subgroups were significantly higher than those of the corresponding serum deprivation subgroups （ all P 〈 0. 01 ） ; The glucose uptake rate was not significantly different among different subgroups, but IGF-1 addition made the glucose uptake increase by about 25% （ all P 〉 0. 05 ）. The GLUT1 expression in the cell membrane of the serum deprivation ＋ IGF-Ⅰ subgroups increased by 15%-20% respectively, however, without significant differences. Conclusion Enhanced sensitivity to trophic withdrawal in the cells with the two Chinese PSI mutations most
出处
《中华医学杂志》
CAS
CSCD
北大核心
2007年第5期336-340,共5页
National Medical Journal of China
基金
国家自然科学基金(30370494)
