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。
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
Abstract: Objective To investigate the secretion of lysosomal Pro-cathepsin L and its contribution to neuronal apoptosis upon lipopolysaccharide (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 cells 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.
Key words:
Lipopolysaccharides,
Microglia,
Lysosomes,
Cathepsins,
Apoptosis,
Cells, cultured
张辉,刘桂冬,楼跃,肖勤,陈生弟. 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[J]. 中国现代神经疾病杂志, 2011, 11(1): 71-75.
ZHANG Hui, LIU Guidong, LOU Yue, XIAO Qin, CHEN Shengdi. The release of lysosomal Pro-cathepsin L of BV-2 cells upon lipopolysaccharide stimulation and its toxicity to neurons[J]. Chinese Journal of Contemporary Neurology and Neurosurgery, 2011, 11(1): 71-75.