Depletion of Glutathione during Oxidative Stress and Efficacy of N-Acetyl Cysteine: An Old Drug with New Approaches

Abstract

Glutathione, a non-protein thiol is most abundant in cells and glutathione-glutathione disulfide is the major redox pair in animal cells. Its synthesis is from two main enzymes gamma glutamyl cysteinyl synthetase and GSH synthetase. Also cysteine availability as N-acetyl cysteine and GSH feedback mechanism determines the reduced glutathione status of the cell. Additionally parenteral NAC, cystine, methionine are effective precursors of cysteine for tissue GSH synthesis. Adequate protein in the diet is crucial for tissue GSH synthesis. The role of NAC as an antioxidant, in gene expression, and regulation of cellular events must be emphasized. GSH deficiency contributes to oxidative stress and it progresses in diseased conditions such as HIV, AIDS, cancer, diabetes, also metabolic syndrome. New knowledge of the nutritional regulation of GSH metabolites is critical to improve health and treat these diseases.