脂多糖刺激星形胶质细胞SOCS-3及促炎性细胞因子的表达

Expression of SOCS-3 and proinflammatory cytokines in cultured astrocytes stimulated by lipopolysaccharide

目的以脂多糖(lipopolysaccride,LPS)刺激,模拟革兰阴性菌感染,观察体外培养大脑皮质星形胶质细胞分泌某些促炎性细胞因子及负性调控分子的变化,为进一步了解脑部炎症中星形胶质细胞的调节机制提供更丰富的实验依据。方法采用改良McCarthy法体外对大脑皮质星形胶质细胞进行培养,抗GFAP抗体荧光鉴定纯度后,用10ng/ml LPS刺激24h后收集细胞和培养上清,Western blotting检测SOCS-3(Suppressor of Cytokine Signaling-3,SOCS-3)蛋白水平,ELISA法检测培养上清中TNF-α和IL-6水平。结果 LPS刺激24h后,星形胶质细胞中SOCS-3有升高趋势,但与正常对照比较差异无统计学意义(P>0.05);星形胶质细胞培养上清中IL-6和TNF-α的水平明显升高,与正常对照比较差异均有统计学意义(P<0.01,P<0.05)。结论 LPS刺激能有效促进星形胶质细胞分泌促炎性细胞因子;SOCS-3的表达与星形胶质细胞分泌细胞因子的变化密切相关,是调控星形胶质细胞适度产生促炎性细胞因子的重要负反馈因子。

Aim To study the aheration of some proinflammatory eytokines and negative regulators in cultured astrocytes after the treatment with lipopolysaccharide （LPS）,and to further understand the modulation mechanism of astrocytes in cerebral inflammation. Methods The astrocytes were isolated and purified in vitro through the modified McCarthy method. After the identification by immunofluorescence,astrocytes were cultured and treated with 10ng/ml of LPS for 24 hours. SOCS-3 protein was determined by Western blot. IL-6 and TNF-α levels were quantified by ELISA. Results After the LPS treatment,SOCS-3 tended to be elevated though without statistical significance （P〉0.05）. IL-6 and TNF-α levels were increased significantly （P〈0.01,P〈0.05）compared with the control. Conclusion LP.S can enhance the production of prointlammatory cytokines in cerebral astrocytes. SOCS-3 expression with the counterbalance roles is closely correlated to variation of inflammatory cytokines in the inflammation.