Glutathione-cysteine

The recent work by Winterbourn and Metodiewa [211] demonstrated that the above values for the rate constant of reaction of DHLA with superoxide might be overestimated. These authors studied the reactions of superoxide with several thiols, glutathione, cysteine, cysteamine, penicillamine, /V-acetylcysteine, dithiothreitol, and captopril and found that thiols reacted with superoxide by a chain mechanism with the regeneration of superoxide. They suggested that the rate constants for the reactions of thiols with superoxide could not be more than 103 ImoN1 s-1. 

Coppellotti, O. 1989. Glutathione, cysteine and acid-soluble thiol levels in Euglena gracilis cells exposed to copper and cadmium. Comp. Biochem. Physiol. 94C 35-40. 

S-Nitroso derivatives of the biological thiols—glutathione, cysteine (115) and homocysteine—have been considered as bioactive intermediates in the metabolism of organic nitrates and the endothelium-derived relaxing factor with properties of nitric oxide. A simple, rapid and reproducible method for separating these thiols from their... 

Acrolein forms adducts with thiols such as glutathione, cysteine, N- acetylcysteine, and others. Such reaction protects tissues and cells from the cytotoxic effects of acrolein or acrolein-releasing substances (Brock et al. 1981 Chaviano et al. 1985 Dawson et al. 1984 Gurtoo et al. 1983 Ohno and Ormstad 1985 Whitehouse and Beck 1975). 

Herbicide absorbed Animals. Metabolites in rat, goat, and by coleoptile hen include glutathione, cysteine, and... 

Transsulphuration The involvement of SAMe leads to the formation of glutathione, cysteine, etc. These substances play an important metabolic role in detoxification processes and in the elimination of reactive oxygen intermediates. 

In experiments, SAMe was found to prevent lipid peroxidation and to normalize the reduced glycogen content of hepatocytes in fiver damage. In further studies, its cytoprotective effect was also confirmed. (163, 166—171, 173, 177—181) This protective effect likewise applied to preneoplastic cell damage. The results concerning the prevention of cholestasis were impressive. In cirrhosis or severe fiver disease, there is a reduction in SAMe synthetase, glutathione, cysteine and phospholipid methyltransferase (together with a simultaneous deficiency in phosphatidylcholine formation, accompanied by disturbed membrane fluidity and decreased activity of Na /K -ATPase and Ca -ATPase). 

Table 1. Chemicals that produce nephrotoxicity through their glutathione/cysteine conjugates.

The toxicity induced by nephrotoxicant glutathione, cysteine, and N-acetylcysteine conjugates can be modified by a variety of compounds. Probenecid, an... 

Table V. Glutathione, cysteine and N—acetyl—cysteine conjugates...

Table VI. Aryl glutathione, cysteine and N-acetyl-cystelne conjugates synthesized by nucleophilic displacement of halogen or some other leaving group Including the one obtained by dlazotlsatlon of arylamlnes.

Addition reactions, synthesis of glutathione, cysteine, and -acetyl-cysteine conjugates, 142... 

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