Effects of oridonin on the progress of apoptosis in human glioma U251 cells and its mechanisms.

Objective To investigate apoptosis-induction effects of oridonin on human glioma U251 cells and its mechanisms in vitro.Methods The MTT method was used to investigate the inhibitory effects of oridonin on U251 cells.Cellular morphological changes were observed by means of phase contrast microscopy and fluorescence microscopy with Annexin V-FITC/PI staining.Apoptosis-induction effects were evaluated by flow cytometry.Expression of bcl-2,bax and caspase-3 were evaluated by Realtime PCR.Results Oridonin could significantly inhibit the growth of U251 cells in a time-and dose-dependent manner.Marked morphological changes of cell apoptosis were observed 24h after the cells were exposed to oridonin.The apoptosis-induction effects of oridonin were in a dose-dependent manner(P0.05).Along with the process of apoptosis,bcl-2 expression was down-regulated and bax and caspase-3 expressions were concurrently up-regulated(P0.05).Conclusion Oridonin can inhibit cell growth by inducing apoptosis in U251 cells via down-regulating expression of bcl-2 and up-regulating that of bax and caspase-3.