Chemopreventive action of Syzygium cumini on DMBA-induced skin papillomagenesis in mice.

Syzygium cumini L. is widely used for the treatment of diabetes in various parts of India. The protective efficacy of S. cumini seed extract (SCE) against peroxidative damage contributing to skin carcinogenesis in Swiss albino mice was tested in the present study. A single topical application of 7,12-dimethyl benz(a)anthracene (100 microg/100 microl acetone), followed 2 weeks later by repeated application of croton oil (1% in acetone three times a week) and continued till the end of the experiment (i.e., 16 weeks) caused a 100% tumor incidence. In contrast, mice treated with the SCE (125 mg/ kg/ b.wt./ animal /day) in either the peri (i.e. 7 days before and 7 days after the application of DMBA) or post-initiation (i.e. from the day of start of croton oil treatment and continued till the end of the experiment) phases demonstrated significant reduction in cumulative numbers of papillomas and tumor incidence (75%). The average latency period in the SCE treated group was also significantly increased (Pre Group - 11.1 weeks; Post Group - 10.9 weeks) as compared with the carcinogen control group (7.9). Results from the present study indicate that the anticarcinogenic activity of SCE during DMBA-induced skin papillomagenesis is mediated through alteration of antioxidant status. Thus, SCE can be considered as a readily accessible, promising novel cancer chemopreventive agent.