熊果酸通过影响Bax 及Bcl.docVIP

熊果酸通过影响Bax 及Bcl 　 作者：　张贵平，黎银燕，吕嘉春，区彗坚 【关键词】 细胞凋亡 Ursolic acid induces apoptosis through effects on Bax and Bcl2 expression in human MCF7 cells 　　【Abstract】 AIM: To study the effects of ursolic acid (UA) on human MCF7 cell apoptosis and the mechanism probably involved. METHODS: MCF7 cells were treated with different concentrations of UA (0, 10, 30, 50 μmol/L ) for 24 h, apoptotic cells with condensed or fragmented nuclei were visualized by Ho33258 staining in a fluorescence microscope. After MCF7cells treated with UA (0, 20, 50 μmol/L ) for 24 h, subG1 peak and cell cycle were detected with PI staining by FCM. After MCF7cells treated with and 50 μmol/L of UA for 24 h, the protein expression of cytochrome c, Bcl2 and Bax were detected by immunofluorescence cell staining (SABCCy3) and the grey levels of immunofluorescence on cytochrome c and Bcl2 and Bax were analyzed with the use of QWin. RESULTS: Twentyfour hours after UA treatment, apoptotic cells increased dosedependently and the morphological changes of MCF7 cells displayed many hallmark features of apoptosis, including chromatin aggregation and fragmented nuclei. SubG1 rates in 0, 20 and 50 μmol/L of UA detected by FCM were 0.05, 0.22 and 0.43 respectively. Compared with 5 mL/L DMSO, 50 μmol/L of UA significantly increased the grey levels of Bax (59.3±7.8, 213.6±7.4, Plt;0.01), cytochrome c (88.2±6.9, 188.1±15.4, Plt;0.01) and the grey ratio of Bax/Bcl2 (1.0±0.1, 2.4±0.4, Plt;0.01) and increased noticeably the grey level of Bcl2 (58.1±6.1, 92.1±12.4, Plt;0.01). Cytochrome c induced by 50 μmol/L of UA released into cytoplasm. CONCLUSION: Apoptosis induced with UA in MCF7 cells is related to increasing the ratio of Bax/bcl2 and releasing cytochrome cdependent apoptotic pathway. Our study indicates that UA may be a potential Chinese medicinal component for breast neoplasm. 　　【Keywords】 ursolic acid; MCF7 cells; apoptosis; genes, Bax; genes, Bcl2; cytochrome c 　　【摘要】 目的： 探讨中药成分熊果酸（ursolic acid, UA）诱导MCF7人乳腺癌细胞的凋亡作用