Lipid peroxidation and antioxidant levels in Anabas testudineus (Bloch) under naphthalene (PAH) stress

Exposure to large concentrations of organic PAH (polycyclic aromatic hydrocarbon) compound naphthalene can potentially accumulate inside the body, damage the cells and causes serious health issues. The current understanding of naphthalene exposure to many food fish species is limited. For a comprehensive understanding of naphthalene toxicity to fish health, dose dependent exposure was carried out in Anabas testudineus, an important food fish of Asia. Fish were exposed to sublethal concentrations of naphthalene (4.2, 4.4, 4.6, 4.8 and 5 mg L-1) for a period of 72 h. Activity analysis of lipid peroxidation and antioxidant enzymes in liver and muscles of the Anabas testudineus showed a marked increase in the lipid peroxidation activity in almost all the experimental groups. In contrast, the enzymatic activity of antioxidants like catalase, glutathione peroxidase and non-enzymatic antioxidant glutathione decreased in both liver and muscle tissue. The results imply that increasing doses of naphthalene induced lipid peroxidation and the decreasing levels of antioxidants were incapable of reducing the stress exerted by naphthalene. This study is beneficial for evaluating the effect of LMW (Low molecular weight) naphthalene on fish and highlights the specific biomarker response signifying PAHs toxicity in fish.

Automated summary

Exposure to naphthalene at different concentrations resulted in increased lipid peroxidation activity and decreased antioxidant enzyme activity in Anabas testudineus, indicating that naphthalene induced lipid peroxidation and antioxidant levels were unable to alleviate the stress caused by naphthalene exposure. This study highlights the importance of evaluating the effect of low molecular weight naphthalene on fish and provides specific biomarker responses for PAHs toxicity in fish.