Abstract: Objective To investigate whether gensenoside Rg1 could induce apoptosis of murine melanoma cells in vitro, and to observe the effect on cell viability when those cells were exposed to both gensenoside Rg1 and anti-neoplastic(MeCCNU). Methods The morphological and ultrastructural changes of the cells treated with gensenoside Rg1(100μmol/L) for 3 or 72 hours were examined by transmission electron microscopy(TEM) and double-fluorescent staining with acridine orange and ethidium bromide. Meanwhile, flow cytometer (FCM) and MTT assay were carried out to evaluate their cell cycle, percentage of apoptotic cells, and cell viability. Results The results of double-fluorescent staining and ultrastructural finding exhibited a characteristic morphological alteration of apoptotic cells. Flow cytometer analysis showed that the percentage of apoptotic cells exposed to both gensenoside Rg1 and MeCCNU was higher than those of cells treated by either of them alone (61.7%). MTT assay demonstrated that gensenoside Rg1(100μmol/L) itself had no cytotoxity, but gensenoside Rg1 vigorously enhanced the cytotoxity of MeCCNU(50μmol/L) when the melanoma cells were concomitantly exposed to them in vitro. Conclusion Gensenoside Rg1 enhances in vitro cytotoxity of MeCCNU, the possible mechanism might be the apoptosis of murine melanoma cells induced in a non-cell cycle selective manner.

Key words: Gensenoside, Melanoma, Apoptosis