脂多糖刺激小胶质细胞分泌Pro-cathepsin L及对神经元凋亡的影响  

The release of lysosomal Pro-cathepsin L of BV-2 cells upon lipopolysaccharide stimulation and its toxicity to neurons

作　　者：张辉[1] 刘桂冬[1] 楼跃[1] 肖勤[1] 陈生弟[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院神经科上海交通大学医学院神经病学研究所,200025

出　　处：《中国现代神经疾病杂志》2011年第1期71-75,共5页Chinese Journal of Contemporary Neurology and Neurosurgery

基　　金：国家自然科学基金资助项目(项目编号:30872728)

摘　　要：目的观察脂多糖刺激对小胶质细胞系BV-2(BV-2细胞)分泌Pro-cathepsin L和神经元凋亡的影响。方法通过脂多糖刺激BV-2细胞产生炎性反应建立炎性细胞模型,Western blotting法分别观察脂多糖刺激前后BV-2细胞条件培养液中Pro-cathepsin L表达水平,以及经Cathepsin L抑制剂预处理前后多巴胺能神经元细胞系PC-12(PC-12细胞)活化Caspase-3表达变化。结果脂多糖刺激BV-2细胞1和3 h后,Pro-cathepsin L表达水平显著增加,与刺激前比较差异均有统计学意义(P=0.015,0.021)。与BV-2细胞共培养并经脂多糖刺激1和3 h后,PC-12细胞活化(Caspase-3表达水平升高,且显著高于刺激前水平(均P=0.000);经Cathepsin L抑制剂预处理及脂多糖刺激1和3 h后,PC-12细胞活化Caspase-3表达水平下降,且显著低于单纯脂多糖刺激组(P=0.005,0.001)。结论小胶质细胞在炎性反应条件下可向细胞外释放Pro-cathepsin L,促进神经元表达活化型Caspase-3,在神经变性疾病发生发展中发挥重要作用。Objective To investigate the secretion of lysosomal Pro- eathepsin L and its contribution to neuronal apoptosis upon lipopolysaecharide （LPS） stimulation. Methods The effect on the release of Pro-cathepsin L in BV-2 cells upon LPS stimulation was determined by Western blotting. Dopaminergic cell line PC-12 cells were cultured with conditioned medium collected from BV-2 cells upon LPS stimulation, then the activated Caspase-3 expression in PC- 12 ceils was determined by Western blotting. After combination with Cathepsin L inhibitor （iCL） and LPS, the activated Caspase-3 expression in PC-12 cells was observed. Results The secretion of Pro-cathepsin L was increased significantly at 1 and 3 h upon LPS stimulation in BV-2 cells （P = 0.015, 0.021）. Expression of activated Caspase-3 in PC-12 cells co-cultured with conditioned medium collected from BV-2 cells upon LPS stimulation at 1 and 3 h was increased （P = 0.000, for all）. However, pretreatment with iCL in BV-2 cells could partially reverse Caspase- 3 activation （P = 0.005, 0.001）. Conclusion Inflammation increases secretion of Pro-cathepsin L in microglia, which can induce the Caspase-3 activation of neurons, which may participate in the pathogenesis of neurodegenerative diseases.

关 键 词：脂多糖类 小神经胶质细胞 溶酶体 组织蛋白酶类 细胞凋亡 细胞 培养的 

分 类 号：R363[医药卫生—病理学]