Effect of DMSO on Apoptosis and Taxol Biosynthesis in Suspension Cultured Taxus cuspidata Cells

The effects of different concentrations of DMSO on cell proliferation, cell viability and secondary product biosynthesis of Taxus cuspidata in suspension cultured cells were studied. Meanwhile, apoptosis was detected with fluorescence dyes PI and Hoechst 33342 used for staining. The results showed that 2% DMSO could decrease the cell viability significantly(Fig.3), suppress cell proliferation(Fig.1), and reduce the DNA content in the nucleus(Fig.2). Some of the cells treated with 2% DMSO showed typical apoptotic morphological changes under fluorescence microscope from the 8th to the 27th day of culture(Plate I b,c,d). In the same time, the yield of taxol was enhanced evidently(Fig.5). These changes in the above description were not observed in the control group and the groups treated by DMSO of concentrations 0.5% and 1%. These findings show that DMSO at a certain concentration induces apoptosis and promotes taxol biosynthesis by Taxus cuspidata cells in suspension culture.