印楝素对小菜蛾胚胎细胞增殖和凋亡的影响

【目的】探讨印楝素对小菜蛾Plutella xyllostella胚胎细胞增殖和凋亡的影响及可能的机制。【方法】将体外培养的小菜蛾胚胎细胞分为印楝素处理组和未处理组,采用CCK-8试剂盒检测细胞增殖的抑制率,激光共聚焦镜检PI染色后的细胞死亡和DAPI染色后的凋亡小体,通过Western-blotting检测各组细胞Caspase-3的表达情况以及通路蛋白Akt的磷酸化水平。【结果】印楝素对小菜蛾胚胎细胞有明显的增殖抑制作用,且呈现浓度依赖性,24 h的IC_(50)为4.4μg·mL~(-1)。印楝素处理后的细胞经PI染色后能明显观察到死亡细胞,DAPI染色后可见凋亡小体;Caspase-3蛋白发生剪切,并且抑制Akt的磷酸化水平。【结论】印楝素对小菜蛾胚胎细胞的增殖有明显的抑制作用,并通过抑制Akt信号通路的活化,诱导细胞产生依赖于Caspase-3的Ⅰ型凋亡。

Effects of azadirachtin on proliferation and apoptosis of Plutella xyllostella embryonic cells

Objective] To investigate the effect and mechanism of azadirachtin on proliferation and apoptosis in Plutella xyllostella embryonic cells.Method]P.xyllostella embryonic cells were divided into azadirachtin treated and untreated groups, the inhibition rate of cells proliferation was detected using CCK-8 kit.The cell death and apoptotic body were observed using laser confocal microscope after stained by PI and DAPI respectively.The expression of Caspase-3 and the phosphorylation of pathway protein Akt were detected using Western-blotting.Result]Azadirachtin had significant inhibitory effect on the proliferation of P.xyllostella embryonic cells, and the effect was dose-dependent.IC50 was 4.4 μg·mL-1 in 24 h.Dead cells could be observed in azadirachtin treated group after stained by PI, and apoptotic body could be found in the same group after stained by DAPI.Caspase-3 protein was cleaved and Akt phosphorylation was inhibited.Conclusion] Azadirachtin has significant inhibitory effect on the proliferation of P.xyllostella embryonic cells.By inhibiting the activation of Akt signaling pathway, azadirachtin can induce cells to produce Caspase-3-dependent type I apoptosis.