Protective roles of tomato paste and vitamin E on cadmiuminduced histological and histochemical changes of liver of oreochromis niloticus (Linnaeus, 1758)

Abstract

The present study was carried out to investigate the potential protective effects of tomato paste (9 mg lycopene kg-1 b.wt.) in comparison with vitamin E (50 mg kg-1 b.wt.) against the impacts of cadmium (Cd) toxicity (4.64 mg L-1, 1/4 of 96 h- LC50) Oreochromis niloticus exposed for 15 and 30 days. Cd impacts were evaluated in terms of histopathological and histochemical characteristics of the liver and hepatopancreas. Various changes have been observed in the liver tissues of the fish exposure to Cd in the two periods. These changes included liver cord disarray, enlargement of ballooning degeneration, dilatation and congestion of some blood vessels with blood cells. A considerable number of hepatocytes showed cytoplasmic vacuolation. Küpffer cells were evident in the dilated hepatic sinusoids. A gradual increase in the damage was noticed by longer period of exposure. The pathologic effect of cadmium on hepatopancreas included a decrease in the size of the acinar cells with an increase in their number. Histochemically, glycogen content decreased in the liver and hepatopancreas with the increase of the period of exposure. These Cd-induced parameters were significantly improved with supplementation of vitamin E and/or tomato paste. These findings were emphasized by liver enzymes ones demonstrating the beneficial supplementation of vitamin E and/or tomato paste in reducing the harmful effects of Cd on the normal enzyme levels and structures of the liver and hepatopancreas. © 2012 Academic Journals Inc.