Abstract: To study the effects of diosmetin from carbonized Cirsium japonicum on apoptosis in human MCF-7 breast cancer cells and its mechanisms. Three flavonoids were isolated and purified from carbonized C. japonicum by silica gel and Sephadex LH-20 chromatography methods. Their structures were elucidated by NMR and MS spectroscopic data and identified as diosmetin(1),acacetin(2) and pectolinarigenin(3). MTS assay was performed to detect the viability of MCF-7 cells treated by different concentrations of diosmetin. The cell apoptosis rate was further analyzed by flow cytometry(FCM). Western blot assay was applied to measure the apoptosis related protein expression levels of PARP,P-JNK. Diosmetin treatment on MCF-7 cells significantly inhibited cell proliferation and induced cell apoptosis. Diosmetin significantly downregulated P-JNK and upregulated cleaved-PARP protein expression. Diosmetin inhibited MCF-7 cell proliferation and induced cell apoptosis by activation of JNK pathway in vitro.

Key words: diosmetin, human breast cancer cell line MCF-7, cell apoptosis, mechanism