目的 探討人參多糖誘導白血病K562細胞凋亡的機制。方法 將對數(shù)生長期K562細胞分成對照組和人參多糖組，對照組細胞常規(guī)培養(yǎng)，人參多糖組細胞培養(yǎng)體系中加入人參多糖0.4 g/L。各組細胞培養(yǎng)48 h后，流式細胞術和Hoechst 33258染色法檢測K562細胞凋亡情況；RT-PCR檢測細胞p38、JNK基因表達；采用免疫熒光實驗檢測細胞中p-p38、p-JNK蛋白表達，測定Caspase-3的活性；Western blotting檢測細胞中p38、JNK、p-p38、p-JNK、cleaved Caspase-3蛋白的變化。結果 與對照組比較，人參多糖組K562細胞凋亡率顯著增加（P＜0.05），出現(xiàn)明顯的細胞核固縮現(xiàn)象，K562細胞p38 mRNA與JNK mRNA明顯增多。免疫熒光檢測顯示，p-p38、p-JNK、cleaved Caspase-3表達明顯增強且向胞核轉(zhuǎn)移；Western blotting檢測顯示，人參多糖組K562細胞p38、JNK總蛋白無明顯變化（P＞0.05）；p-p38、p-JNK、cleaved Caspase-3有增加的趨勢（P＜0.05）。結論 人參多糖能促進K562細胞凋亡，其作用可能是通過影響MAPK信號傳導通路實現(xiàn)的。

Abstract: Objective To investigate the mechanisms of the ginseng polysaccharide (GPS) on the apoptosis of leukemia K562 cells. Methods The K562 cells at logarithmic growth phase were divided into control and GPS groups. The cells in the control group were normally treated and cells in GPS group were incubated with 0.4 g/L GPS. Flow cytometry and Hoechst 33258 staining were used to demonstrate the apoptotic changes in the two groups after incubation for 48 h. Gene expression of p38 and JNK were detected by RT-PCR. The immunofluorescence staining was used to detect the activation of Caspase-3 and expression of p-p38 and p-JNK protein. The changes of p38, JNK, p-p38, p-JNK, and cleaved Caspase-3 protein were detected by Western blotting. Results Compared with the control group, the apoptosis rate of K562 cells in GPS group was significantly increased (P < 0.05). After the treatment with GPS, chromatin condensation was observed when the cells were stained by Hochest 33258. The expression of p38 mRNA and JNK mRNA was obviously increased. The immunofluorescence staining results showed that the expression of p-p38, p-JNK, and cleaved Caspase-3 proteins was significantly increased in GPS group and obviously transferred to the nucleus. The Western blotting results showed that there was no significant change in total p38 and JNK protein (P < 0.05), but an increasing trend in p-p38, p-JNK, and cleaved Caspase-3 was observed (P < 0.05). Conclusion GPS could induce K562 cell apoptosis and the effect may be achieved through MAPK signal transduction pathway.

國家自然科學基金面上項目（81171929，31271368）；重慶市教委基金項目（KJ110308）