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 (CdCl(2)) and diphenyl diselenide (PhSe)(2) was investigated. Mouse liver, kidney and testes were used to evaluate delta-aminolevulinate dehydratase (delta-ALA-D) activity and thiobarbituric acid-reactive substances (TBARS) levels. CdCl(2) and (PhSe)(2), at different concentrations, caused an inhibition in delta-ALA-D activity of liver, kidney and testes. The inhibitory effect of (PhSe)(2) in hepatic and renal delta-ALA-D activity was attenuated by interaction of this compound with CdCl(2) at non-inhibitory concentration. Dithiothreitol (DTT), but not ZnCl(2), restored the inhibition observed in delta-ALA-D activity in all tissues. This suggests an involvement of sulfhydryl groups in delta-ALA-D inhibition. TBARS levels were increased by CdCl(2) in all tissues and (PhSe)(2) was able to abolish this increase. The results demonstrate that the association between CdCl(2) 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).