Biochemical and histological alterations induced by UV-328 in the gill tissue of Zebra fish (Danio rerio) and its reversal by Dimethoxy curcumin

Abstract

The presence of Benzotriazole UV Stabilizer-328 (UV-328) in different biological and natural systems is of fast, regular concern in recent days due to their exuberant use in sunscreens. To learn more about its role of oxidative damage in the gills and to uncover the protective nature of DiMC, we evaluated its sub-lethal toxicity in Zebra fish gill tissue and also evaluated the potential defensive role of Dimethoxy curcumin (DiMC). Grown-up Zebra fish were exposed to 55 µg/L of UV-328 and 50mg/kg of DiMC for four weeks. After the completion of 28 days, gill tissues were dissected out and assessed for their response to oxidative stress, antioxidant enzymes status, and histopathological changes. Our results demonstrated that antioxidant such as glutathione (GSH) levels and the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and Glutathione S-transferase (GST) were all diminished in the gill tissue along with the profound increase in lipid peroxidation (measured as TBARS) in the UV-328-treated group. Histopathological lesions, for instance, inflammatory cell infiltration with a minimal congestion in primary lamellae, diffuse epithelial hyperplasia and fusion of secondary lamellae, multifocal mucus cell hyperplasia were seen in the UV-328-treated gill tissue of Zebra fish. The UV-328-induced oxidative, biochemical, and histological alterations were almost reverted back to normal in the DiMC enhanced group, suggesting its remediative efficacy against UV-328-induced respirotoxicity. Based on our findings, exposure to UV-328, even at a low level, could be toxic, causing oxidative stress, antioxidant depletion, and pathological gill damage in Zebra fish. And these alterations were almost recuperated in DiMC supplemented group which signifies its protective influence against UV-328 toxicity. Keywords: UV-328; Oxidative stress; Antioxidants; Histopathology; Zebra fish