Effects of 8-Oxo-dGuo on S-Nitrosation of Cysteine and N-Nitrosation of Tryptophan

抄録

Addition of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxo-dGuo), a common oxidative-damaged nucleoside of 2′-deoxyguanosine, to the reaction of N-acetylcysteine with diethylamine NONOate, an NO donor, at neutral pH increased the yield of N-acetyl-S-nitrosocysteine. Addition of 8-oxo-dGuo to the reaction of N-acetyltryptophan with diethylamine NONOate accelerated decomposition of the formed N-acetyl-N′-nitrosotryptophan. In the reaction of N-acetylcysteine with N-acetyl-N′-nitrosotryptophan, the concentration of N-acetyl-S-nitrosocysteine greatly increased with the addition of 8-oxo-dGuo. In all experiments, no change in 8-oxo-dGuo concentration was observed. These results indicate that 8-oxo-dGuo can act as a vehicle of NO, and may affect signal transduction associated with NO in humans.