Glutathione (GSH) serves as a nucleophilic co-substrate to glutathione transferase in the detoxification of xenobiotics and is an essential electron donor to glutathione peroxidases in the reduction of hydroperoxides.[1] [2][3] GSH ethyl ester is a cell-permeable derivative of GSH that undergoes hydrolysis by intracellular esterases to release GSH. [4] Effective transport of GSH ethyl ester has been used to protect cells against damage from radiation, oxidants, and various toxic compounds including heavy metals.[5] [6]

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[1]. Jakoby, W.B. The glutathione S-transferases: A group of multifunctional detoxification proteins. Advances in Enzymology and Related Areas of Molecular Biology 46, 383-414 (1978).
[2]. Baillie, T.A., and Slatter, J.G. Glutathione: A vehicle for the transport of chemically reactive metabolites in vivo. Acc. Chem. Res. 24(9), 264-270 (1991).
[3]. Bedia, C. Glutathione: Metabolism and function. (1976).
[4]. Wellner, V.P., Anderson, M.E., Puri, R.N., et al. Radioprotection by glutathione ester: Transport of glutathione ester into human lymphoid cells and fibroblasts. Proceedings of the National Academy of Sciences of the United States of America 81(15), 4732-4735 (1984).
[5]. Zeevalk, G.D., Manzino, L., Sonsalla, P.K., et al. Characterization of intracellular elevation of glutathione (GSH) with glutathione monoethyl ester and GSH in brain and neuronal cultures: Relevance to Parkinson’s disease. Experimental Neurology 203(2), 512-520 (2007).
[6]. Kelly-Aubert, M., Trudel, S., Fritsch, J., et al. GSH monoethyl ester rescues mitochondrial defects in cystic fibrosis models. Human Molecular Genetics 20(14), 2745-2759 (2011).