prosapogenin and dioscin

The authors have isolated prosapogenin B of dioscin (P.B) newly from Dioscorea futschauensis R. Kunth (Dioscoreaceae) and found that P.B could significantly inhibit the cell proliferation of several human cancer cell lines for the first time. The objective of this paper was designed to investigate whether P.B could inhibit cancer cell proliferation by inducing apoptosis.. Morphological changes of cell nuclei were observed under invert fluorescence microscope and transmission electron microscope. The changes in the cell size distribution were analyzed by Coulter Multisizer II particle analyzer. DNA ladder and apoptotic cells were analyzed respectively by DNA agarose gel electrophoresis and flow cytometry.. The K562 cells treated with 10 micromol/L P.B for 24 hours showed morphological characteristics of apoptotic cells, such as decrease in cellular volume, nuclear chromatin condensation, nuclear fragmentation, and plasma membrane bleb formation. The treatment of K562 cells with 10 micromol/L P.B for 6, 12,and 24 hours caused the increase of the detected DNA ladder and the decrease of normal size cells both in a time-dependent manner. The percentage of apoptotic bodies detected in the sub-G(0)/G(1) peak region by flow cytometry was also increased time-dependently as analyzed as 6.12% for 6 hours, 35.6% for 12 hours and 45.7% for 24 hours treatments, respectively.. These results suggested that P.B exerts its anti-proliferative effect on K562 cells through inducing apoptosis of the cells.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Diosgenin; Flow Cytometry; Humans; K562 Cells; Microscopy, Electron, Scanning; Saponins

By activity-guided fractionation, three known steroidal saponins, prosapogenin A of dioscin, dioscin and gracillin, were isolated from the total saponin fraction of Dioscorea coiletti var. hypoglauca as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. The compounds also exhibited cytotoxic activity against the cancer cell line K562 in vitro. The structures of the compounds were elucidated on the basis of chemical evidence and IR, FAB-MS, 1H-NMR, 13C-NMR, and two-dimensional NMR (2D-NMR) analysis.

Topics: Antineoplastic Agents; Carbohydrate Conformation; Carbohydrate Sequence; Diosgenin; Drugs, Chinese Herbal; Glycosides; Molecular Sequence Data; Saponins; Spirostans; Tumor Cells, Cultured