Further studies on the resolution of human mercapt‐ and nonmercaptalbumin and on human serum albumin in the elderly by high‐performance liquid chromatography

Abstract

High‐performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) on Asahipak GS‐520 showed at least two peaks, the principal component corresponding to human mercaptalbumin (HMA) and the secondary one to nonmercaptalbumin (HNA). HPLC analysis of HSA on Asahipak ES‐520 N showed three peaks, the principal component corresponding to HMA, the secondary one to HNA having mixed disulfide with cysteine or glutathione and the tertiary one to HNA oxidized higher than mixed disulfide. Two kinds of rapid HPLC for the resolution of HSA into HMA and HNA were developed by the present authors. Using these HPLC, the present authors found a significant decrease in the fraction of HMA in the elderly.

Oxidation of the albumin thiol to sulfenic acid and its implications in the intravascular compartment

“…The fraction of oxidized albumin is also increased in diabetes mellitus (53), disorders of the temporomandibular joint (54), senile cataract (55), and invasive surgery (56). Furthermore, it has been shown that the fraction of oxidized albumin also increases with aging (26,35) and intense exercise (57).…”

“…The heterogeneity of albumin can be revealed, among other techniques, by anion exchange-hydrophobic interaction chromatography (26) and mass spectrometry (27,28). The fraction containing the reduced thiol is known as mercaptalbumin and comprises ~7 0% of total albumin, whereas the nonmercaptalbumin fraction consists mainly of mixed disulfides between Cys34 and low molecular weight thiols, mostly cysteine (25%) (27).…”

Albumin thiol oxidation and serum protein carbonyl formation are progressively enhanced with advancing stages of chronic kidney disease

“…The Cys-34 of HSA makes up approximately 80% of the total free thiol content in plasma [15] and the state of Cys-34, i.e., the redox state of HSA, is thus indicative of the degree of short-term systemic oxidative stress because of the short half-life (*20 days) of the albumin molecule [15]. We have developed a convenient high-performance liquid chromatography (HPLC) system for the clear separation of HSA into HMA and HNA [16,17], and we have extensively studied the dynamic changes of HSA(Cys-34)-redox state under various physiologic [18][19][20] and pathophysiologic states, such as hepatic [21,22], renal [5,[23][24][25][26], diabetic [27], and other diseases [28][29][30].…”

Human astrocytes and aortic endothelial cells actively convert the oxidized form of albumin to the reduced form: reduced albumin might participate in redox regulation of nerve and blood vessel systems

“…We have developed a convenient HPLC method for separation of HSA into HMA and HNA [5,6] and have extensively studied the dynamic changes of the HSA-thiol redox state under various physiologic [7][8][9][10] and pathophysiologic states, for example hepatic [11,12], renal [13][14][15][16][17][18], diabetic [19,20], and other diseases [21][22][23].…”