N-磷酰化二肽甲酯诱导K562细胞凋亡

背景与目的：磷被认为是生命代谢过程中的中心元素,许多N-磷酰化氨基酸和N-磷酰化肽具有重要的生物活性和药用价值。本实验研究N-磷酰化二肽甲酯诱导人慢性髓性白血病K562细胞凋亡作用。方法：采用四甲基偶氮唑盐还原法[3-（4,5-dimethylthiazo-2-yl)-2,5-diphenyl-tetrazolium bromide,MTT]检测15种N-磷酰化二肽甲酯对K562细胞的增殖抑制作用;用Hoeches33258染色后观察细胞核的形态学变化;DNA琼脂糖凝胶电泳,双染法和流式细胞术检测细胞凋亡。结果：MTT法筛选出细胞增殖抑制活性较好的化合物是（DIPP-L-Leu)2-L-Lys-OCH3,IC50为22.66μmol/L;Hoechst33258染色后细胞核出现明显的凋亡形态学变化;DNA琼脂糖凝胶电泳出现典型的梯状条带;流式细胞仪检测到早期的凋亡细胞。结论：（DIPP-L-Leu)2-L-Lys-OCH3能够诱导K562细胞凋亡。

Apoptosis of K562 cell induced by N-phosphoryl dipeptide methyl ester

BACKGROUND & OBJECTIVE: Phosphorus plays a crucial role in metabolism. Some N-phosphoryl amino acids and N-phosphopeptides have important biological activities and medicinal value. The current study was designed to investigate the apoptosis of K562 cells induced by N-phosphoryl dipeptide methyl ester. METHOD: Cell growth inhibition of K562 cells induced by 15 kinds of N-phosphoryl dipeptide methyl esters was analyzed by using MTT assay. The nuclei were stained by Hoechst 33,258 and the morphologic changes were observed. DNA agarose gel electrophoresis, double-staining, and flow cytomery were used to detect early apoptosis of K562 cells. RESULT: (DIPP-L-Leu)2-L-Lys-OCH3 was the compound screened with MTT method that had better growth inhibiting activity with the IC50 of 22.66 mumol/L. Chromatin condensation and nuclear fragmentation were seen under fluorescence microscope in the cells treated with Hoechst 33,258. DNA agarose gel electrophoresis showed nuclear fragmentation (DNA ladder). Early apoptotic cells were also detected by flow cytometry. CONCLUSION: These results suggest that(DIPP-L-Leu)2-L-Lys-OCH3 could induce the apoptosis of K562 cells.