Benzo(a)pyrene induces lung toxicity and inflammation in mice: prevention by carvacrol.

Benzo(a)pyrene (B(a)P) is an environmental pollutant which causes various lung toxicities. The present study was designed to evaluate the protective effects of carvacrol, a monoterpenic phenol against B(a)P-induced lung toxicity. In this study, Swiss albino mice were pretreated with carvacrol (25 mg/kg and 50 mg/kg) orally for 7 consecutive days before administering oral B(a)P (125 mg/kg). Preventive efficacy of carvacrol was assessed in terms of membrane oxidation, antioxidant enzyme activities, histopathological changes, and inflammatory (iNOS, NF-κB, and COX-2) markers. Carvacrol pretreatment in the two doses restored B(a)P-induced lipid peroxidation and increased the activities of antioxidant enzymes. Protein expressions of iNOS, NF-κB, and COX-2 in the lung tissue were found to be upregulated by B(a)P. Carvacrol treatment, however, downregulated their expressions by decreasing the marker of positive stained cells and restored the histopathological architecture of lung tissue. Our results suggest that carvacrol can be used as a protective agent against B(a)P-induced lung toxicity and inflammation.