Chemoprotective effect of boeravinone B against 1,2-dimethyl hydrazine induced colorectal cancer in rats via suppression of oxidative stress and inflammatory reaction.

Background: Colorectal cancer (CRC) has few or no symptoms and is often diagnosed at its end stage. Boeravinone B (BB) is a natural rotenoid which induces an antioxidative effect and has been used in cancer prevention. In this study, we scrutinized the chemoprotective effect of BB against 1,2dimethyl hydrazine (DMH) induced CRC in rats.

Methods: Subcutaneous administration of DMH (40 mg/kg) was used for the induction of CRC in rats, followed by oral administration of BB. The body weight, tumor volume, tumor incidence, and total number of tumors were estimated in all rat groups rats except the normal group. Antioxidant parameters, phase I and II enzymes, and inflammatory cytokines and parameters were estimated at the completion of the study.

Results: DMH induced group rats exhibited a tumor incidence of 100% along with several tumors/polyps per tumor‑bearing rat, while BB treatment remarkably suppressed the incidence of tumors and suppressed polyps per tumor bearing rat. BB treatment significantly (P<0.001) altered the level of antioxidant parameters, phase I and phase II enzymes, and cytokines such as TNF-α, IL-1β, IL-4, IL-6, and IL-10, and treatment significantly (P<0.001) suppressed the level of inflammatory cytokines, including cyclooxygenase-2 (COX-2), prostaglandin E (PGE), and inducible nitric oxide synthase (iNOS).

Conclusions: BB treatment considerably suppresses colon cancer via its antioxidant and anti-inflammatory mechanism.