Selenium and mercury levels in rat liver slices co-treated with diphenyl diselenide and methylmercury

Organoseleno-compounds have been investigated for its beneficial effects against methylmercury toxicity. In this way, diphenyl diselenide (PhSe)(2) was demonstrated to decrease Hg accumulation in mice, protect against MeHg-induced mitochondrial dysfunction, and protect against the overall toxicity of this metal. In the present study we aimed to investigate if co-treatment with (PhSe)(2) and MeHg could decrease accumulation of Hg in liver slices of rats. Rat liver slices were co-treated with (PhSe)(2) (0.5; 5 A mu M) and/or MeHg (25 A mu M) for 30 min at 37 A degrees C and Se and Hg levels were measured by inductively coupled plasma mass spectrometry (ICP-MS) in the slices homogenate, P1 fraction, mitochondria and incubation medium. Co-treatment with (PhSe)(2) and MeHg did not significantly alter Se levels in any of the samples when compared with compounds alone. In addition, co-treatment with (PhSe)(2) and MeHg did not decrease Hg levels in any of the samples tested, although, co-incubation significantly increased Hg levels in homogenate. We suggest here that (PhSe)(2) could exert its previously demonstrated protective effects not by reducing MeHg levels, but forming a complex with MeHg avoiding it to bind to critical molecules in cell.