胆固醇转运抑制剂U18666A对星形胶质细胞自噬-溶酶体的影响

Effect of cholesterol transport inhibitor U18666A on autophagy-lysosome in astrocytes

目的观察胆固醇转运抑制剂U18666A(UA)对星形胶质细胞自噬-溶酶体活性的影响。方法用5μg·mL-1UA作用于原代培养的星形胶质细胞12,24和48 h,用Western blot检测自噬标志蛋白LC3和溶酶体标志蛋白LAMP1的表达,用免疫荧光检测微管相关蛋白1A/1B轻链3(LC3)及溶酶体相关膜蛋白1(LAMP1)与淀粉样前体蛋白(APP)的定位表达。结果5μg·mL-1UA能增加星型胶质细胞LC3和LAMP1的蛋白表达,且LC3及LAMP1与APP在细胞内共定位表达。结论UA可能通过激活自噬-溶酶体系统活性,增强APP的代谢,促进β淀粉样蛋白的生成。

Objective To investigate the influence of cholesterol transport inhibitor U18666A(UA)on autophagy-lysosome activity in primary cultured astrocytes.Methods The primary cultured astrocytes were treated with 5μg·mL-1 UA for 12,24 and 48 h.The expressions of microtubule-associated protein 1A/1B-light chain 3(LC3)and lysosome-associated membrane protein 1(LAMP1)proteins were detected using western blotting.The localization of LC3 or LAMP1 with amyloid precursor protein(APP)were determined by immunofluorescence.Results UA increased the expressions of LC3 and LAMP1 proteins,which co-localized with APP in astrocytes.Conclusion These Results suggest that UA may enhance the metabolism of APP and promote the formation of Aβby activating the activity of autophagy-lysosome system.