目的 探討人參多糖誘導(dǎo)白血病K562細(xì)胞凋亡的機(jī)制。方法 將對(duì)數(shù)生長(zhǎng)期K562細(xì)胞分成對(duì)照組和人參多糖組，對(duì)照組細(xì)胞常規(guī)培養(yǎng)，人參多糖組細(xì)胞培養(yǎng)體系中加入人參多糖0.4 g/L。各組細(xì)胞培養(yǎng)48 h后，流式細(xì)胞術(shù)和Hoechst 33258染色法檢測(cè)K562細(xì)胞凋亡情況；RT-PCR檢測(cè)細(xì)胞p38、JNK基因表達(dá)；采用免疫熒光實(shí)驗(yàn)檢測(cè)細(xì)胞中p-p38、p-JNK蛋白表達(dá)，測(cè)定Caspase-3的活性；Western blotting檢測(cè)細(xì)胞中p38、JNK、p-p38、p-JNK、cleaved Caspase-3蛋白的變化。結(jié)果 與對(duì)照組比較，人參多糖組K562細(xì)胞凋亡率顯著增加（P＜0.05），出現(xiàn)明顯的細(xì)胞核固縮現(xiàn)象，K562細(xì)胞p38 mRNA與JNK mRNA明顯增多。免疫熒光檢測(cè)顯示，p-p38、p-JNK、cleaved Caspase-3表達(dá)明顯增強(qiáng)且向胞核轉(zhuǎn)移；Western blotting檢測(cè)顯示，人參多糖組K562細(xì)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(shì)（P＜0.05）。結(jié)論 人參多糖能促進(jìn)K562細(xì)胞凋亡，其作用可能是通過影響MAPK信號(hào)傳導(dǎo)通路實(shí)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(guó)家自然科學(xué)基金面上項(xiàng)目（81171929，31271368）；重慶市教委基金項(xiàng)目（KJ110308）