Anti-tumour and immunomodulating activities of diosgenin, a naturally occurring steroidal saponin.

Diosgenin is a naturally occurring steroidal saponin abundantly present in many medical plants. In this study, diosgenin could significantly inhibit the growth of sarcoma-180 tumour cells in vivo, and remarkably increase thymus and spleen weights of S-180-bearing mice and upgrade the secretion level of TNF-alpha in serum. Moreover, diosgenin could stimulate lymphocyte transformation and enhance phagocytic capability of macrophages in vitro, and remarkably promoted the secretion of NO and TNF-alpha in macrophages. These results suggested that diosgenin could improve both specific and non-specific cellular immune responses, and the anti-tumour effects of diosgenin were achieved by immunostimulating properties instead of direct cytotoxicity.