淫羊藿甙对小鼠腹腔巨噬细胞体外增殖、吞噬和产生NO的影响

Effect of icariin on proliferation,phagocytosis and NO production of murine peritoneal macrophages in vitro

无菌分离小鼠腹腔巨噬细胞,制备单细胞悬液,加入不同终浓度的淫羊藿甙孵育4 h后,加入细菌脂多糖LPS(终浓度20 mg/L)48 h后以MTT法检测其增殖;加药孵育4 h后,分别加入直径1μm和2μm的微球(终浓度1×1010/L),5 h后利用流式细胞术(FCM)检测吞噬情况;加入LPS(终浓度20 mg/L)24 h后Griess试剂盒检测巨噬细胞NO的量。结果显示ICA在终浓度1.5、3.0μmol/L时能明显抑制LPS刺激的巨噬细胞增殖(P<0.01)和NO的产生,并促进其吞噬微球的功能。提示ICA可能抑制LPS信号转导从而抑制巨噬细胞增殖,并且通过抑制其活化,下调iNOS有关的炎症因子,使NO减少;对于未活化的巨噬细胞,ICA可能通过上调其吞噬功能,增强固有免疫系统来抵御病原体侵入。

The single cell suspension of murine peritoneal macrophages was prepared under sterile condition and stimulated with LPS at a final concentration of 20 mg/L.Then,the proliferation of macrophages was measured by MTT assay 48 hours later,Macrophages in this cell suspension were treated with different concentrations of icariin(ICA) after 4 hours incubation and addition of microbeads with a diameter of 1 to 2 μm(final concentration 1×1010/L),and the condition of phagocytosis by macrophages was observed by flow cytometry(FCM) 5 hours later.The amount of NO produced in macrophages 24 hours later was detected by Griess kit.It was found that both 1.5 and 3.0 μmol/L of ICA inhibited proliferation and NO production of macrophages stimulated by LPS and promoted the ability of macrophages to engulf microbeads.These results suggest that ICA can inhibit the transduction of LPS-signals leading to proliferation of macrophages and also inhibit its activation by down-regulating the iNOS-involved inflammatory factors,thus to decrease the production of NO.However,to the un-activated macrophages,ICA up-regulates phagocytic functions and promotes the innate immunity to resist invasion of pathogens.