Inhibitory Effect And Mechanism Of Polyphyllin D And Formosanin C On U251Human Glioblastoma Cells

Objective：To investigate inhibitory effects and mechanism of Polyphyllin D(Paris saponin(PS)I)and formosanin C(PSII) on U251human glioblastoma cells.Methods：Glioma cell line U251was cultured in vitro. Different treatments(PSI, PSII)wereadded into the medium cultured human malignant glioma U251cells．And blank controlgroup was also established. The effect of PSI and PSII on the proliferation of glioma cellsU251in vitro was examined using MTT assay. The nuclear morphology of apoptotic cellswas detected by Hoechst33258fluorescent staining. Apoptotic rate was quantified by flowcytometry (FCM) using Annexin-Ⅴ/PI dual staining method. Western blot analysis wasused to evaluate the changes of Fas，caspase-8and caspase-3proteins in U251cells.Results：PSI and PSII induced U251cells apoptosis showed a time-and dose-dependentmanner. The proliferation of glioma cells was remarkable inhibited by PSI. PSII took thesecond place（P <0.05）. Typical morphological changes of apoptosis were observed inU251cells with Hoechst33258staining. The early apoptotic rates of the PSI，PSII groupswere all significantly higher than that of the control groups（F=81.434, P=0.000）. Theyboth made the U251cells increase the expression of Fas，caspase-8and caspase-3. Thedifferences were statistically significant（P <0.05）.Conclusion：PSI and PSII inhibited the proliferation of glioma cells in vitro. They increased theexpression of Fas， Caspase-8and Caspase-3and accelerated cell apotosis， which might be the mechanism of inhibition.