Protective effect of melatonin, methionine and zink on cadmium nephrotoxicity: histopathologically, histochemically and AgNORs quantitation

ABSTRACT

Cadmium [Cd] is a highly toxic heavy metal that is naturally present in the environment. Chronic exposure to Cd causes hepatotoxicity and nephrotoxicity. The present study aimed to study the protective effect of melatonin, methionine and zinc against histopathological, histochemical and proliferative effects of cadmium on the kidney of rats. A total of 80 female albino rats were included in this study and divided into 8 groups. They were injected intraperitonealy with cadmium chloride [CdCl2] [2 mg / kg b.w.], melatonin [10 mg / kg b.w.], methionine [42.8 mg / b.w.] or zinc [20 mg / kg b.w.] with or without CdCl2 daily for 10 days. Treatment with CdCl2 induced marked tubular cell degeneration with large areas of interstitial hemorrhage.There were marked destruction of the brush borders with decrease in glycogen and protein contents of the degenerated tubules. AgNORs count significantly increased. Injection of melatonin or methionine to CdCl2 treated rats resulted in improvement of Cd-induced histopathological and histochemical changes. AgNORs count significantly decreased. Zinc injection partially protected the kidney from Cd-induced effects. In conclusion, melatonin and methionine have a more protective effect than zink against Cd nephrotoxicity