Association between diphenyl diselenide and cadmium chloride attenuates the toxicity of both in tissues of mice in vitro

The in vitro effect of association between cadmium chloride (CdCl2) and diphenyl diselenide (PhSe)2 was investigated. Mouse liver, kidney and testes were used to evaluate δ-aminolevulinate dehydratase (δ-ALA-D) activity and thiobarbituric acid-reactive substances (TBARS) levels. CdCl2 and (PhSe)2, at different concentrations, caused an inhibition in δ-ALA-D activity of liver, kidney and testes. The inhibitory effect of (PhSe)2 in hepatic and renal δ-ALA-D activity was attenuated by interaction of this compound with CdCl2 at non-inhibitory concentration. Dithiothreitol (DTT), but not ZnCl2, restored the inhibition observed in δ-ALA-D activity in all tissues. This suggests an involvement of sulfhydryl groups in δ-ALA-D inhibition. TBARS levels were increased by CdCl2 in all tissues and (PhSe)2 was able to abolish this increase. The results demonstrate that the association between CdCl2 and (PhSe)2 attenuates the toxicity of both compounds and the possible mechanisms of this protection are due to complex formation between cadmium and selenium and involves the antioxidant activity of (PhSe)2.