ABSTRACT
In 1984, the glutathione peroxidase-like activity of ebselen, 2-phenyl-1,2-benzisoselenazol-3(2H)-one, a synthetic selenium-containing heterocycle, was described. Ebselen has been found to have an antioxidant activity in model systems which is independent of glutathione (GSH). This chapter reviews the action and role of ebselen as an antioxidant in the presence or absence of GSH. The activity of ebselen as a radical scavenger has been measured in the oxidation of methyl linoleate emulsions in aqueous dispersions induced either by a hydrophilic or lipophilic radical initiator. Ebselen suppresses the ferrous-ion-induced oxidation of methyl linoleate emulsions dose-dependently, implying that ebselen suppresses the oxidation by decomposing lipid hydroperoxides, which act as an oxygen radical precursor or by sequestrating iron ion. Ebselen metabolism has been studied in perfused liver, and microsomal metabolism has been further investigated. The concept of transport of ebselen in the organism is that it is bound to proteins and that there is an interchange with low-molecular-weight thiols within cells and tissues.
