Effect of Withania somnifera on DMBA induced carcinogenesis

Administration of an extract of Withania somnifera was found to reduce two stage skin carcinogenesis induced by DMBA (dimethyl benzanthracene) and cro ton oil. Withania somnifera was administered at a concentration of (20 mg/d ose/animal i.p.) consecutively on 5 days prior to DMBA administration and c ontinued twice weekly for 10 weeks. After the 180th day of carcinogen admin istration, all of the animals developed papilloma in the control group wher eas only six out of 12 animals developed papilloma in the treated group. A total of 11 papillomas were found in the control group while only six devel oped them in the Withonia somnifera treated group. Enzyme analysis of skin and liver showed significant enhancement in antioxidant enzymes such as GSH , GST, Glutathione peroxides and Catalases in Withania. somnifera treated g roup when compared with the control. The elevated level of lipid peroxide i n the control group was significantly inhibited by Withania somnifera admin istration. These studies indicate that Withania somnifera could reduce the papilloma induced alterations to the antioxidant defense systems. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.