Włodek L
Institute of Medical Biochemistry, N. Copernicus Academy of Medicine, Kraków, Poland.
Acta Biochim Pol. 1988;35(4):307-17.
The sulfhydryl groups of L-cysteine and reduced glutathione (GSH) react nonenzymatically with formaldehyde (F), acrolein (Al), acetaldehyde (AA), malondialdehyde (DAM), pyruvate (P), oxoglutarate (oxo-G) and glucose (G) to form thiazolidine derivatives. These reactions show different velocities and the adducts formed show different stabilities. The equilibrium constants K, as well as the rate constants kr for the reverse reaction, show considerable variation. The carbonyls reveal higher reactivity with sulfhydryl group of L-Cys than with those of GSH, and the stability of the adducts is higher than that of GSH. Al, F and AA react more rapidly with both thiol compounds than the other carbonyls, but the adducts are less stable. The sulfhydryl groups level of bovine serum albumin as well as those of high- and low-molecular thiols of human plasma is reduced in the presence of Al, F or DAM.
L-半胱氨酸和还原型谷胱甘肽（GSH）的巯基可与甲醛（F）、丙烯醛（Al）、乙醛（AA）、丙二醛（DAM）、丙酮酸（P）、氧代戊二酸（oxo-G）和葡萄糖（G）发生非酶反应，形成噻唑烷衍生物。这些反应呈现出不同的速度，且所形成的加合物具有不同的稳定性。平衡常数K以及逆反应的速率常数kr表现出显著差异。羰基与L-半胱氨酸的巯基反应活性高于与GSH的巯基反应活性，且加合物的稳定性高于GSH的加合物。Al、F和AA与这两种硫醇化合物的反应比与其他羰基的反应更快，但加合物的稳定性较低。在Al、F或DAM存在的情况下，牛血清白蛋白的巯基水平以及人血浆中高、低分子硫醇的巯基水平会降低。
