Antitumour and radioprotective action of Podophyllum hexandrum

A significant antitumour effect of P. hexandrum, a herb thriving at Himalayas (2500-4000 m), was observed in strain 'A' mice carrying solid tumours developed by transplanting Ehrlich ascites tumour (EAT). Subtoxic well tolerated sequential doses of aqueous extract of P. hexandrum (a daily dose of 34.5 mg/kg b.w. for 15 days) enhanced tumour doubling time (TDT) from 1.94 +/- 0.26 days to 19.1 +/- 2.5 days. However, no synergism was revealed between radiation and P. hexandrum, though both independently manifested antitumour effects. In normal mice, pre-irradiation administration of extract of P. hexandrum protected mice in a dose dependent manner (optimal dose being 34.5 mg/kg body.wt. rendering 72% survival for 30 days) against whole body lethal irradiation of 10 Gy. Radioprotective properties of P. hexandrum were found to be comparable to synthetic radioprotectors like diltiazem etc.