Effects of catechin hydrate in benzo[a]pyrene-induced lung toxicity: roles of oxidative stress, apoptosis, and DNA damage

The major sources for human exposure to Benzo [a] pyrene (B[a]P) are contaminated food, water, and inhalation of polycyclic aromatic hydrocarbon. B[a]P is a well-known human genotoxic carcinogen (IARC Group 1). It has a tumorigenic potential in virtually all in vivo experimental animal model systems. The study aimed to evaluate the effect of catechin hydrate (CH) against B [a] P-induced toxicity in the lung of adult albino rats. Thirty-six adult male albino rats (150-200 g) were divided into six groups, three control groups, and three experimental groups: B[a] P-treated group, (CH)-treated group, and B[a] P+(CH)-treated group. At the end of the fourth week of the study, blood samples and lung tissues were obtained for the biochemical and genotoxicity, RT-PCR, histopathological, and immunohistochemical investigations, respectively. Our results clarified that B[a] P exposure caused a subsequent decrease in the activities of antioxidant enzymes (SOD, CAT), and conversely (MDA) levels elevated markedly. Also, B[a] P induced DNA damages and activated the apoptotic pathway, presented by upregulated Bax, caspase-3, and downregulated Bcl-2 gens. However, treatment with CH increased antioxidant enzymes as well as regulated apoptosis. Discernible histological changes in the lung also supported the protective effects of CH. These findings suggested that CH is an effective natural product that attenuates Benzo [a] pyrene-induced lung toxicity.