Toxicological effects of the concurrent administration of cadmium and arsenic through the food chain on the liver and kidney of rats

Abstract

Abstract Background Our environment is filled with a mixture of toxic elements. Objectives This study seeks to assess the effects of exposure to cadmium and arsenic through the food chain on the liver and kidney of rats. Methodology Adult male albino rats were exposed to experimental feed of which the protein composition was made of fish exposed to cadmium and arsenic for 1 month at a concentration of 0.4 mg cadmium or/and arsenic/100 ml water for 1 and 3 months. Samples of feed and tissue were assayed for cadmium and arsenic load. Tissue homogenates were used for biochemical analysis and the estimation of the expression levels of mRNA of Bax and Bcl2 genes in the liver and kidney of rats were carried out. Samples of tissues were also used for histological analysis. Results Results show a greater accumulation of metals in the liver than kidney of rats after the 1-month exposure of which the trend changed after the 3-month exposure. Alterations in enzymatic activities and levels of MDA and GSH were also recorded. Significant (P < 0.05) alterations in the level of mRNA expression of the Bax and Bcl2 genes were observed in all groups compared to the control for both duration of treatment. Treatment-related lesions were also observed for the various groups from the histopathological analysis. Conclusion The cadmium-contaminated diet was found to be more toxic to the kidney while the arsenic-contaminated diet was found to be toxic to the liver. In addition, the present study has shown that the toxicity of a mixture of As + Cd cannot be predicted from the toxic mechanisms of the single components.