Glycated serum protein

Because all glycated serum proteins are fructosammes and albumin is the most abundant serum protein, measurement of fructosamine is thought to be largely a measure of glycated albumin, but this has been questioned by some investigators. Although the fructosamine assay can be automated and is cheaper and faster than GHb, there is a lack... 

S. Blincko, D. Colbert, W. G. John, and R. Edwards, A reliable non-separation fluorescence quenching assay for total glycated serum protein A simple alternative to nitroblue tetrazohum reduction, Xnn. Clin. Biochem., 37 (2000) 372-379. 

Yatscoff RW, Tevaarwerk G), MacDonald JC. Quantification of nonenzymically glycated albumin and total serum protein by affinity chromatography. Clin Chem 1984 30 446-9. 

Stolba, P., Hatle, K., Kmakova, A., Streda, M., and Streka, L., 1987, Effect of ascorbic acid on non-enzymatic glycation of serum protein in vitro and in vivo, Diabetologia 30 585A. 

Rutin, quercetin 3-rutinoside, i.e., 3-rhamnoglucoside, has been reported to suppress glycation,609 but it is only sparingly soluble in water. Nagasawa el al.6W have therefore examined the water-soluble 4G-a-D-glucopyranosyl derivative (G-rutin), obtained from a sugar factory. Streptozotocin-treated rats were fed for 4 weeks on a 20% casein diet, when they showed an increase in fructosyllysine obtained on hydrolysis of their protein however, when their diet had been supplemented with 0.2% G-rutin, the increase was reduced by 20% for kidney protein. Supplementation reduced AGE accumulation, as measured with an anti-AGE monoclonal antibody, in the serum and kidney proteins to the level of the control rats. Supplementation inhibited aldose reductase activity in the kidney, but not in the liver. 

Long-term incubation of methylglyoxal-glycated bovine serum albumin and cytochrome c produces cross-links between these proteins. In the presence of... 

Affinity chromatography Has a wide number of uses and can be applied to the isolation and purification of virtually all biomolecules. Specific applications include nucleic acid purification, protein purification from cell and tissues extracts, and antibody purification from blood serum. There are a number of matrices used for the construct, and some examples of these and their uses are as follows heparin columns to separate cholesterol lipoproteins, lectin columns to separate carbohydrate groups, and phenyl boronate columns to separate glycated haemoglobins. 

Glycation may adversely affect the structure or the function of the protein involved. For example, glycation of the LDL receptor and of proteins in the LDL particle may interfere with the normal fit of LDL particles with their specific receptors. As a result, less circulating LDL is internalized into cells by receptor-mediated endocytosis, and the serum LDL cholesterol level rises. 

N. A. Ansari, Moinuddin, K. Alam, and A. Ali, Preferential recognition of Amadori-rich lysine residues by serum antibodies in diabetes mellitus Role of protein glycation in the disease process. Hum. Immunol, 70 (2009) 417-424. 

In this Section, I also include studies on protein glycation which is also known to produce protein folding disorders. This year, the structure of fructose-derived glycated products of Leu- and Met-enkephalin were established by NMR and their improved chemical and enzymatic stability in phosphate-buffered saline (pH 7.4) and human serum at 37 °C (over non-glycated) shown. In a similar study, the site specificity, extent and nature of modification of the tetrapeptide Leu-Ser-Lys-Leu incubated with D-Glc or D-Fru in methanol or phosphate buffer (pH 5.7, 7.4, 8.0) were compared for the production of Amadori (1-deoxy-D-fructosyl derivatives) and Heyne s rearrangement products (N-alkylated GlcN/ManN derivatives). Mannose and lauryl-mannoses (synthesised by lyase-catalysed condensation) were compared for the interaction with cysteine in Maillard product formation and 5-hydroxy-3-mercapto-2-pentanone was identified in the... 

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