OBJECTIVETo study the effect of chrysin in inducing apoptosis of human hepatic carcinoma cells and explore the possible mechanism.

METHODSHuman hepatic carcinoma SMMC-7721 cells treated with DMSO or chrysin at different concentrations (5-200 μg/mL) were examined for changes in the cell proliferation using CCK-8 assay. The morphological changes of SMMC-7721 cells were observed in response to treatment with 5, 10, or 20 μg/mL chrysin, and the changes in the cell nuclei were observed using DAPI nuclear staining. Annexin Ⅴ-FITC/PI flow cytometry was used to determine the cell apoptosis rate. The changes in the apoptosis-related proteins (PARP and caspase-3) and MAPKs signal pathway were detected with Western blotting.

RESULTSChrysin treatment obviously suppressed the proliferation of SMMC-7721 cells in a dose-dependent manner below the concentration of 60 μg/mL. Chrysin (20 μg/mL) also caused significantly increased cell apoptosis and significant cleavage of PARP and caspase-3. Chrysin significantly activated MAPKs signaling pathway in a time-and dose-dependent manner, with the peak activation level occurring at 15 min. Pretreatment of the cells with specific inhibitors of the MAPKs pathway obviously inhibited the effect of chrysin in inducing cell apoptosis.

CONCLUSIONSChrysin inhibits the proliferation and promotes apoptosis of SMMC-7721 cells by regulating the activation of MAPKs signaling.