【摘要】 目的研究冬凌草甲素促进U937人淋巴瘤细胞分化的巨噬细胞吞噬凋亡小体的机制。方法光学显微镜下计数检测吞噬率,PKC活力检测盒测定PKC活力,吖啶橙染色,Hoechst 33258染色及W estern b lot法。结果酪氨酸蛋白激酶(PTK)抑制剂gen iste in和蛋白激酶C(PKC)广泛的抑制剂stauroporine均不同程度地抑制了冬凌草甲素诱导U937分化的巨噬细胞对凋亡小体的吞噬增强效果。2.7μmol.L-1的冬凌草甲素处理U937细胞后,时间依赖性地增加了PKC活力。ERK磷酸化抑制剂PD98059阻断了冬凌草甲素的吞噬增强作用。免疫印迹结果显示冬凌草甲素作用U937细胞后,ERK磷酸化程度增加,而PD98059逆转了ERK磷酸化。结论冬凌草甲素增强U937细胞对凋亡小体的吞噬作用,其吞噬机制是通过激活PTK和PKC激酶,导致下游ERK途径活化,从而增强吞噬过程。更多还原

【Abstract】 Aim To study the mechanisms of oridonin-enhanced phagocytosis of apoptotic bodies by macrophage-like U937 cells.Methods Photomicroscopical observation,PKC activity assay,acridine orange staining,Hoechst 33258 staining,and Western blot analysis were used.Results Oridonin-augmented phagocytosis was suppressed by either protein tyrosine kinase（PTK） inhibitor genistein or protein kinase C（PKC） inhibitor stauroporine.Exposure of U937 cells to 2.7 μmol·L^-1 oridonin caused an increase in PKC activity time dependently.In addition,ERK inhibitor PD98059 blocked phagocytic stimulation as well as the increased expression of phsophorylated ERK in response to oridonin.Conclusion Oridonin enhanced macrophage-like U937 cells to ingest apoptotic bodies by upregulation of PTK activity and thus PKC activation,resulting in phosphorylation of the downstream mediator,ERK.更多还原