Reactions of Reduced Glutathione with Some Methylated Selenium Compounds

Abstract

Selenium biochemistry has been of general interest since the discovery of selenium as the toxic agent in certain plants, which when ingested by animals causes a definite disease syndrome and even death. Early scientists suggested that the logical place in the body for toxic selenium compounds to attack was at the various sites occupied by sulfur. In 1939 a study was published which indicated that reduced glutathione (GSH), a thiol, protected rats against death from a minimum fatal dose of selenium given as sodium selenite. Since this discovery, the reaction of GSH with various selenium containing compounds has been the subject of much research. Improved technology has led to new insights about the reaction of GSH with selenium compounds. This, coupled with recent advances in metabolite and toxicity studies, has led to the proposal of a pathway for the metabolism of selenium which involves the reaction of GSH with several methylated selenium compounds. The studies reported here have been done in an attempt to investigate those proposed reactions. Specifically, the reactions under investigation are: 1) The reaction of GSH with methylseleninic acid (CH3SeO2H), 2) The reaction of GSH with dimethyl diselenide (CH3SeSeCH3), 3) The reaction of GSH with dimethyl selenoxideCH3)2SeO]