N-Acetylcysteine Displaces Glutathionyl-Moieties from Hg2+ and MeHg+ to Form More Hydrophobic Complexes at Near-Physiological Conditions

The anthropogenic release of Hg is associated with an increased human exposure risk. Since Hg2+ and MeHg+ have a high affinity for thiols, their interaction L-glutathione (GSH) within mammalian cells fundamentally involved in toxicological chemistry excretion. To gain insight into the these mercurials multiple small molecular weight we investigated competitive interactions GSH N-acetylcysteine (NAC) at near-physiological conditions, using liquid chromatographic approach. This approach injection each mercurial onto reversed-phase (RP)-HPLC column (37 °C) PBS buffer mobile phase containing 5.0 mM to simulate cytosolic conditions being detected effluent by inductively coupled plasma atomic emission spectrometer (ICP-AES). When was amended up 10 NAC, gradually increasing retention times both were observed. explain this behavior, experiment NAC replicated 50 Tris (pH 7.4), Hg-containing fractions analyzed electrospray ionization mass spectrometry. results revealed presence Hg(GS)(NAC) Hg(NAC)2 MeHg(GS) MeHg(NAC) MeHg+, which suggests that coordination/displacement GS-moieties from more hydrophobic can behavior. biotransformations observed they are relevance as provide biomolecular explanation some obtained when animals administered NAC.