Fig. 5

Effects of honokiol and temozolomide (TMZ) on insults to murine GL261 glioma cells. Murine GL261 cells were exposed to honokiol (40 μM), TMZ (100 μM), and their combination for 72 h. Cell morphology was observed by light microscopy (a). Cell viability was assayed using a colorimetric method (b). Cell autophagy was analyzed by flow cytometry. Murine GL261 glioma cells were pretreated with 1 mM 3-methyladenine (3-MA), an inhibitor of cell autophagy, for 1 h and then exposed to honokiol (40 μM), TMZ (100 μM), and their combination for 72 h. Cell autophagy (c) and cell apoptosis (d) were quantified using flow cytometry. Each value represents the mean ± SEM for n = 6. *, ^#, and ⁺, values significantly (p < 0.05) respectively differ from the control, TMZ-, and honokiol+TMZ-treated groups