神经酰胺介导粒细胞凋亡机理初探

Induction of apoptosis by ceramide in human promyelocytic cells and its mechanism

目的：观察神经酰胺对ＨＬ６０及中性粒细胞（ＰＭＮ）凋亡产生的影响，探讨其在粒细胞发生过程中可能的调节作用。方法：采用ＤＮＡ凝胶电泳，流式细胞术，光镜及ＲＴＰＣＲ等技术对细胞进行凋亡鉴定及相关基因ｂｃｌ２，ｃｍｙｃｍＲＮＡ表达分析。结果：神经酰胺（Ｃ２ｃｅｒａｍｉｄｅ），肿瘤坏死因子（ＴＮＦα）及长春新碱（Ｖｉｎｃｒｉｓｔｉｎｅ）均可不同程度地诱导ＨＬ６０及成熟ＰＭＮ产生凋亡，ＣＰＫ激活剂ＰＭＡ，Ｄｉａｃｙｌｇｌｙｃｅｒｏｌ无诱凋作用，并对ＴＮＦα，Ｃ２ｃｅｒａｍｉｄｅ及Ｖｉｎｃｒｉｓｔｉｎｅ诱导的凋亡有不同程度的抑制；上述药物刺激后ｂｃｌ２，ｃｍｙｃｍＲＮＡ表达在ＨＬ６０细胞中呈明显下调趋势，ｃｍｙｃｍＲＮＡ表达在ＰＭＮ中也呈轻度下调。结论：神经酰胺可作为ＨＬ６０、ＰＭＮ胞内介质参与凋亡信号的传导，且与ＣＰＫ途径及ｂｃｌ２，ｃｍｙｃ基因表达相关。

Objective: To determine the effects of ceramide on apoptosis and regulation in granulocytes differentiation processes. Methods: DNA fragmentation, FACS , light microscope and RT PCR were employed to determine the apoptosis and bcl 2,c myc mRNA levels of granulocytes. Results: C 2 ceramide, TNFα and Vincristine all resulted in a time and dose dependent apoptosis of PMN and HL 60 cells.They also induced down regulation of bcl 2,c myc mRNA expressions in HL 60 cells and a light down regulation of c myc mRNA expression in PMN. A proper dose of phorbol ester (PMA) and diacylglycerol could not induce cell growth suppression but inhibite apoptosis induced by the drugs above. Conclusion: Ceramide was a mediator of apoptosis in PMN and HL 60 cell. The transduction of apoptotic signal was correlated with the CPK pathway,the down regulation of bcl 2 and c myc mRNA expression.