中文摘要：

目的：通过体外建立1型星形胶质细胞（T1A）衰老模型,研究衰老T1A中β-淀粉样蛋白1-40（Aβ1-40）及相关蛋白的表达变化。方法：采用振荡培养与差速贴壁法分离纯化新生SD（Sprague-Dawley）大鼠的T1A,免疫细胞化学标记检测体外培养21d（21DIV）及90d（90DIV）的T1A中β-淀粉样蛋白1-40（Aβ1-40）的表达;以WesternBlot检测微管相关蛋白1A/1B轻链3（LC3）、caspase-3及Bcl-2的表达水平。结果：体外长程培养的T1A中Aβ1-40蛋白表达增加,同时90DIV组细胞中LC3II及活化的caspase-3表达水平提高,Bcl-2表达水平降低。结论：研究结果提示衰老的T1A表达Aβ,细胞内自噬及凋亡活性增强,在年龄相关的神经变性过程中,T1A的衰老可促进神经元的损伤,衰老T1A表达的Aβ很可能是Alzheimer病老年斑的重要来源。

英文摘要：

Objective：The present study was to establish an experimental model of type 1 astrocytes（T1A）aging in vitro,and investigate the expressive changes of β-amyloid protein 1-40（Aβ1-40）and related proteins in aged T1A.Methods：Using shake culture and differential adhesion,neonatal Sprague-Dawley rat cortical T1A were separated and purified.With the immunocytochemical labeling,the expressions of Aβ1-40 were observed in T1A cultured for 21 and 90 d in vitro（DIV）.Microtubule-associated protein 1A/1B-light chain 3（LC3）,caspase-3 and Bcl-2 were evaluated by Western Blot.Results：The results showed that in long-term T1A cultures,there was an increase in proteins that positive for Aβ1-40.Simultaneously,the generation of LC3II and activated caspase-3 were enhanced,and the expression of Bcl-2 was decreased in 90 DIV.Conclusion：These results suggest that Aβ was expressed in aged T1A.Besides,the activity of autophagy and apoptosis was enhanced,and aged T1A may contribute to exacerbating neuronal injury in age-related neurodegenerative processes,and Aβ expressed by aged T1A may be an important source of senile plaque in Alzheimer＇disease（AD）.