Chemoprotective effect of all-trans retinoic acid (ATRA) on oxidative stress and lung metastasis induced by benzo(a)pyrene.

Chemoprevention is regarded as one of the most promising and realistic approaches in the prevention of cancer. All-trans retinoic acid (ATRA) is an active metabolite of vitamin A under the family retinoids, derived by irreversible oxidation of retinol (vitamin A), the parent compound for all natural retinoids. The aim of the present study is to divulge the chemopreventive and chemoprotective nature of ATRA during benzo(a)pyrene (B(a)P) induced lung cancer development in BALB/c mice. Administration of B(a)P (50 mg/kg body weight) to mice resulted in increased lipid peroxides (LPO), lipid hydroperoxides (LOOH) and nitric oxide (NO) with concomitant decrease in the levels of tissue anti-oxidants like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and vitamin C. ATRA supplementation (0.585 mg/kg body weight) attenuated all these alterations, which indicates the anti-cancer effect that was further confirmed by histopathological analysis. Overall, the above data show that the anti-cancer effect of ATRA is more pronounced when used as an chemopreventive agent against B(a)P-induced lung carcinogenesis.