The role of bound lipid and transition metal in the formation of fluorescent advanced glycation endproducts by human serum albumin

Glycation of proteins leads to the formation of advanced glycation endproducts (AGEs) of diverse molecular structure and biological function. Serum albumin derivatives modified to minimal and high extents by methylglyoxal and glucose in vitro have been used in many studies as model AGE proteins. The early and advanced glycation adduct contents of these proteins were investigated using the 6-aminoquinolyl-N-hydroxysuccinimidyl-carbamate (AQC) chromatographic assay of enzymic hydrolysates. AGEs derived from methylglyoxal, glyoxal and 3-deoxyglucosone, the hydroimidazolones Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1), Nδ-(5-hydro-4-imidazolon-2-yl)ornithine (G-H1) and Nδ-[5-(2,3,4-trihydroxybutyl)-5-hydro-4-imidazolon-2-yl]ornithine (3DG-H1), bis(lysyl)imidazolium cross-links methylglyoxal-derived lysine dimer (MOLD), glyoxal-derived lysine dimer (GOLD), 3-deoxyglucosone-derived lysine dimer (DOLD), monolysyl adducts N∊-(1-carboxyethyl)lysine (CEL), N∊-carboxymethyl-lysine (CML) and pyrraline, other AGEs, Nδ-(4-carboxy-4,6-dimethyl-5,6-dihydroxy-1,4,5,6-tetrahydropyrimidin-2-yl)ornithine (THP), argpyrimidine and pentosidine, and fructosyl-lysine were determined. AGEs with intrinsic fluorescence (argpyrimidine and pentosidine) were assayed without derivatization. Human serum albumin (HSA) glycated minimally by methylglyoxal in vitro contained mainly MG-H1 with minor amounts of THP and argpyrimidine. Similar AGEs were found in prothrombin glycated minimally by methylglyoxal and in Nα-t-butyloxycarbonyl-arginine incubated with methylglyoxal. HSA glycated highly by methylglyoxal contained mainly argpyrimidine, MG-H1 and THP, with minor amounts of CEL and MOLD. HSA glycated minimally by glucose in vitro contained mainly fructosyl-lysine and CML, with minor amounts of THP, MG-H1, G-H1, 3DG-H1, argpyrimidine and DOLD. HSA glycated highly by glucose contained these AGEs and pyrraline, and very high amounts (≈8mol/mol of protein) of fructosyl-lysine. Most AGEs in albumin glycated minimally by methylglyoxal and glucose were identified. Significant proportions of arginine and lysine-derived AGEs in albumin modified highly by methylglyoxal, and lysine-derived AGEs in albumin modified highly by glucose, remain to be identified.

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Synthesis and secretion of macrophage colony stimulating factor by mature human monocytes and human monocytic THP-1 cells induced by human serum albumin derivatives modified with methylglyoxal and glucose-derived advanced glycation endproducts

Immunology Letters ◽

10.1016/0165-2478(96)02601-6 ◽

1996 ◽

Vol 53 (1) ◽

pp. 7-13 ◽

Cited By ~ 29

Author(s):

Evelyn A. Abordo ◽

Marie E. Westwood ◽

Paul J. Thornalley

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Advanced Glycation Endproducts ◽

Human Monocytes ◽

Colony Stimulating Factor ◽

Advanced Glycation ◽

Glycation Endproducts ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Stimulating Factor

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The Immune Tolerance Role of the HMGB1-RAGE Axis

Cells ◽

10.3390/cells10030564 ◽

2021 ◽

Vol 10 (3) ◽

pp. 564

Author(s):

Haruki Watanabe ◽

Myoungsun Son

Keyword(s):

Immune Responses ◽

Immune Tolerance ◽

Lupus Erythematosus ◽

Advanced Glycation Endproducts ◽

High Mobility ◽

Chromatin Binding ◽

Advanced Glycation ◽

Glycation Endproducts ◽

Extracellular Milieu

The disruption of the immune tolerance induces autoimmunity such as systemic lupus erythematosus and vasculitis. A chromatin-binding non-histone protein, high mobility group box 1 (HMGB1), is released from the nucleus to the extracellular milieu in particular environments such as autoimmunity, sepsis and hypoxia. Extracellular HMGB1 engages pattern recognition receptors, including Toll-like receptors (TLRs) and the receptor for advanced glycation endproducts (RAGE). While the HMGB1-RAGE axis drives inflammation in various diseases, recent studies also focus on the anti-inflammatory effects of HMGB1 and RAGE. This review discusses current perspectives on HMGB1 and RAGE’s roles in controlling inflammation and immune tolerance. We also suggest how RAGE heterodimers responding microenvironments functions in immune responses.

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Allysine and α-Aminoadipic Acid as Markers of the Glyco-Oxidative Damage to Human Serum Albumin under Pathological Glucose Concentrations

Antioxidants ◽

10.3390/antiox10030474 ◽

2021 ◽

Vol 10 (3) ◽

pp. 474 ◽

Cited By ~ 1

Author(s):

Carolina Luna ◽

Alexis Arjona ◽

Carmen Dueñas ◽

Mario Estevez

Keyword(s):

Oxidative Stress ◽

Plasma Concentration ◽

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Typical Feature ◽

Advanced Glycation ◽

Chemical Mechanisms ◽

Fasting Plasma ◽

Insight Into

Understanding the molecular basis of the disease is of the utmost scientific interest as it contributes to the development of targeted strategies of prevention, diagnosis, and therapy. Protein carbonylation is a typical feature of glyco-oxidative stress and takes place in health disorders such as diabetes. Allysine as well as its oxidation product, the α-amino adipic acid (α-AA) have been found to be markers of diabetes risk whereas little is known about the chemistry involved in its formation under hyperglycemic conditions. To provide insight into this issue, human serum albumin was incubated in the presence of FeCl3 (25 μM) and increasing glucose concentrations for 32 h at 37 °C. These concentrations were selected to simulate (i) physiological fasting plasma concentration (4 mM), (ii) pathological pre-diabetes fasting plasma concentration (8 mM), and pathological diabetes fasting plasma concentration (12 mM) of glucose. While both allysine and α-AA were found to increase with increasing glucose concentrations, the carboxylic acid was only detected at pathological glucose concentrations and appeared to be a more reliable indicator of glyco-oxidative stress. The underlying chemical mechanisms of lysine glycation as well as of the depletion of tryptophan and formation of fluorescent and colored advanced glycation products are discussed.

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