Chemopreventive effect of chrysin, a dietary flavone against benzo(a)pyrene induced lung carcinogenesis in Swiss albino mice

Chemoprevention is considered as one of the most promising and realistic approaches in the prevention of lung cancer. Chrysin, a naturally occurring dietary flavone widely found in Passiflora family of plants and honey, has been studied extensively for its chemopreventive properties. The objective of present study is to divulge the chemopreventive role of chrysin against benzo(a)pyrene [B(a)P] induced lung carcinogenesis in Swiss albino mice. B(a)P was administered orally (50 mg/kg body weight) twice a week for four weeks to induce lung cancer in mice. The body weight, lung weight, tumor incidence, lipid peroxidation, carcinoembryonic antigen, enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase) and non-enzymatic antioxidants (reduced glutathione, vitamin E and vitamin C) were estimated. Further, histopathological analysis of lung tissue and western blotting analysis of PCNA, COX-2 and NF-κB were also carried out. Administration of B(a)P resulted in increased lipid peroxides and carcinoembryonic antigen with concomitant decrease in the levels of both enzymatic antioxidants and non-enzymatic antioxidants. Chrysin treatment (250 mg/kg body weight) significantly attenuated all these changes thereby showing potent anti lung cancer effect. Further, the anticancer effect of chrysin was confirmed by histopathology of lungs, and immunoblotting analysis of PCNA, COX-2 and NF-κB, where chrysin supplementation downregulated the expression of these proteins and maintained cellular homeostasis. Overall, these findings confirm the chemopreventive potential of chrysin against B(a)P induced lung cancer in Swiss albino mice.