STAT5通路抑制剂对脂多糖诱导RAW264.7细胞的保护作用研究

Protective effect of STAT5 pathway inhibitor on RAW264.7 cells induced by lipopolysaccharide

目的观察信号传导及转录激活因子(STAT)5通路抑制剂对经脂多糖(LPS)诱导的小鼠巨噬细胞RAW264.7细胞株一氧化氮(NO)和诱导型一氧化氮合成酶(iNOS)表达的影响。方法将处于对数期的RAW264.7细胞分为空白对照组、STAT5通路抑制剂对照组、LPS诱导组和STAT5通路抑制剂低、中、高浓度组,实时定量聚合酶链式反应(RT-PCR)法测定iNOS mRNA的表达量,Western blot测定iNOS以及磷酸化STAT5(p-STAT5)的蛋白表达量。结果RAW264.7细胞培养24 h后,空白对照组、STAT5通路抑制剂对照组、LPS诱导组以及STAT5通路抑制剂低、中、高浓度组细胞中NO的含量差异有统计学意义(F=25.69,P<0.05);低、中、高浓度STAT5通路抑制剂对RAW264.7细胞释放NO的抑制率差异有统计学意义(F=132.49,P<0.05)。空白对照组、STAT5通路抑制剂对照组、LPS诱导组和STAT5通路抑制剂低、中、高浓度组细胞iNOS mRNA以及蛋白质的表达量比较差异有统计学意义(F=123.59、23.37,P<0.05)。空白对照组、STAT5通路抑制剂对照组、LPS诱导组和STAT5通路抑制剂低、中、高浓度组细胞p-STAT5/STAT5表达比较差异有统计学意义(F=12.07,P<0.05)。结论STAT5通路抑制剂能够抑制RAW264.7细胞iNOS的表达以及NO的产生,其机制可能与抑制STAT5磷酸化的表达有关。

Objective To observe the effect of signal transduction and activator of transcription(STAT)5 pathway inhibitors on the expression of nitric oxide(NO)and inducible nitric oxide synthetase(iNOS)in mouse macrophage RAW264.7 cell line induced by lipopolysaccharide(LPS).Methods RAW264.7 cells in log phase were divided into the following groups:blank control group,STAT5 pathway inhibitor control group,LPS induced group and STAT5 pathway inhibitor low-,medium-and high-concentration group.The expression of iNOS mRNA was measured by real-time quantitative polymerase chain reaction(RT-PCR),and the protein expression of iNOS and phosphorylated STAT5(p-STAT5)was measured by Western blot.Results After 24 hours of culture,there were significant differences in NO content among the blank control group,STAT5 pathway inhibitor control group,LPS induced group and low-,medium-and high-concentrations of STAT5 pathway inhibitor groups(F=25.69,P<0.05);there were significant differences in NO release rate in RAW264.7 cells among low,medium and high concentrations of STAT5 pathway inhibitor preparations(F=132.49,P<0.05).The expression of iNOS mRNA and protein in blank control group,STAT5 pathway inhibitor control group,LPS induced group and STAT5 pathway inhibitor low-,medium-and high-concentration groups were significantly different(F=123.59,23.37,P<0.05).The expression of p-STAT5/STAT5 in blank control group,STAT5 pathway inhibitor control group,LPS induced group and STAT5 pathway inhibitor low-,medium-and high-concentration group was statistically significant(F=12.07,P<0.05).Conclusion STAT5 pathway inhibitor can inhibit the expression of iNOS and the production of NO in RAW264.7 cells,and its mechanism may be related to the inhibition of STAT5 phosphorylation.