Cytochrome P450 and its role in metabolism of dicofol in Channa punctatus and Heteropneustes fossilis
1*Dawa Bhutia and 2Joydeb Pal
1*P.G. Department of Zoology, Darjeeling Government College, Darjeeling-734101 (India) 2Ecology and Toxicology Laboratory, Department of Zoology, University of North Bengal, Darjeeling- 734013 (India)
ABSTRACT
Pesticides and their derivatives are frequently exposed to aquatic organisms, such as fish, that live in and use the aquatic environment. Pesticide biotransformation is the first step in ensuring fish species survival. Cytochrome P450 (CYP 450) is the primary enzyme responsible for pesticide biotransformation and also serves as a biomarker for assessing aquatic environmental health. The ability of dicofol, an organochlorine pesticide, to induce CYP 450 in fish Channa punctatus and Heteropnesutes fossilis after treatment for 5, 10, and 15 days with 1/3 sub-lethal concentration (15.2 and 12.1 μg/L ) of 96 hour LC50 value calculated in the laboratory was investigated in this study. The activities of LSI, total CYP 450 content, 7-ethoxyresorufin O-deethylase, N,N-dimethylaniline demethylse, aniline hydroxylase, and erythromycin N-demethylase were examined in liver microsomes. In comparison to their respective control, all of the enzyme activities were significantly increased in the dicofol-treated groups in both fish species. In both species, CYP1A-mediated activity was the most noticeable of all the activities. Significant induction was also seen in LSI and total CYP 450 content. The present study demonstrates that dicofol has the ability to induce CYP1A, CYP2B, CYP2E1, and CYP3A4 in the liver of fish, Channa punctatus and Heteropnesutes fossilis.