Responses of glutathione to brief exercise in diabetes mellitus

ABSTRACT

Glutathione [GSH] acts as a substrate for glutathione peroxidase to remove peroxides and serves as scavenger for hydroxyl and oxygen free radicals, and prevents oxidation of hemoglobin to methemoglobin in red blood cells [Halliwell and Gutteridge, 1985]. Tissue GSH status, i.e., the concentrations and ratio of GSH and glutathione disulfide [GSSG] is known to be changed by oxidative stress induced by strenuous exercise [Lew et al., 1985]. Previous reports indicated that blood concentration of GSH is decreased, whereas GSSG levels are elevated significantly after acute exercise [Lew et aL, 1985]. However, the mechanism for the observed changes in GSH oxidoreductive status and contents with exercise is unknown. GSH is mainly synthesized in the liver and released to the blood [Meister and Anderson, 1983]. The uptake of GSH by peripheral tissues involves many enzymes [Meister and Anderson, 1983]. Release of GSH from the liver during exercise is controlled by some hormones like glucagon, and resulted in elevation of GSH concentration in skeletal muscle [Meister and Anderson, 1983]. The purpose of this study is to determine, if acute brief exercise alters the contents and oxidoredox status of erythrocytes GSH in healthy humans and compare these responses of GSH to diabetic patient