Glutathione determination and a study of the activity of glutathione-peroxidase, glutathione-transferase, and glutathione-reductase in renal transplants

Abstract

The aim of this work is to study the temporary variation of oxidative stress in renal transplants, both in plasma andin erythrocytes (CR). In order to do so, we determined total glutathione (GST) levels, both oxidized (GSSG) and reduced (GSH), and the activity of enzymes, glutathione peroxidase (G-px), glutathione reductase (G-red) and glutathione transferase (GSt), in renal transplant patients. Determinations were made 48 h before the transplant 1 week and 2 weeks after the renal transplant. The results obtainedconfirm a high ‘‘oxidative stress’’ rate, resulting from the equilibrium between the production of free radicals andthe activity of antioxidants, the former being higher proportionally. Immediately after the transplant there is an increase of oxidative stress, which results in an increase of G-red, a marked decrease of G-px in plasma andin erythrocytes (CR) andan abrupt drop both in GST levels in plasma andin GSG (as well as in the [GSH]/[GSSG] relationship). As times goes on, after the transplant, there is a significant improvement in the activity of antioxidant enzymes, but there is no normalization, which is easily seen in the fact that total glutathione levels andthe activity of the various enzymes approach the average values of the control group.