Abstract: Objective To investigate the role of saikosaponin d in the autophagy of glioma C6 cells and its mechanism. Method CCK⁃8 was used to detect the cell proliferation ability of the glioma C6 cells treated by saikosaponin d with final concentrations of 0 μmol/L (Control group), 2 μmol/L, 4 μmol/L, 6 μmol/L, 8 μmol/L, 10 μmol/L and 12 μmol/L, respectively. The effects of saikosaponin d with concentrations of 8 μmol/L on the proliferation and migration of glioma C6 cells were detected by clonal formation experiments and scratch experiments, respectively. Western blot and qRT⁃PCR were used to detect the expression of autophagy⁃related proteins Beclin1, LC3 and AKT/mTOR signaling pathway⁃related proteins and genes in glioma C6 cells. Results Compared with the Control group, all the other concentrations of saikosaponin d could inhibit the proliferation of glioma C6 cells, and the proliferation inhibition rate increased with the increase of drug concentration (all P<0.01). After the treatment of 8 μmol/L saikosaponin d for 24 h, compared with the Control group, the clone number of glioma C6 cells was significantly reduced (479.33±30.66 vs 258.66±73.35, P<0.01), the cell migration rate was significantly decreased ［(70.83±4.29) % vs (19.47±1.71) %, P<0.001］, and the protein and mRNA expression levels of autophagy⁃related proteins Beclin1 and LC3 were significantly increased (all P<0.01), while the protein and mRNA expression levels of AKT and mTOR were decreased (all P<0.01). Conclusions Saikosaponin d may induce autophagy, and inhibit the proliferation and migration of glioma C6 cells by inhibiting the AKT/mTOR signaling pathway.

Key words: Gliomas, Saikosaponin d, Autophagy, AKT, mTOR