Pathophysiological changes in Rohu (Labeorohita, Hamilton) fingerlings following arsenic exposure

Abstract

Arsenic (As), a toxic environmental contaminant and a human carcinogen, has become a major public health problem. Fish has been among the most commonly used models in ecotoxicology and biomedical research and has helped in understanding many complex diseases, thereby providing clues for developing remedial measures. An experimental study was conducted to investigate the early signs and symptoms and pathophysiological changes in the major carp rohu (Labeo rohita) following arsenic exposure. Fishes were exposed to arsenic at concentrations of 0.0 (control), 0.5, 1.0, 2.5, 5, 10 and 15 ppm for 12 days. At ≥10 ppm arsenic exposure, prominent gross changes observed were skin lesions (patchy discolouration—dark and white patches—on the skin) and cataract. Histopathological examinations revealed fatty degeneration and necrosis of hepatocytes, glomerular necrosis and tubular degeneration in kidney. Stress protein analysis by immunoblotting revealed over expression of Hsp90 in liver of exposed fishes at ≥10 ppm concentrations. The typical skin lesions and cataract in fish resulting from arsenic toxicity are reported for the first time. These findings have clinical implications for human health and vision.