Glycated proteins

Glucose may auto-oxidize (like other alphahydroxy-aldehydes) and generate hydroxyl radicals in a transition-metal-catalysed reaction, and induce both fragmentation and conformational changes in glycated proteins (Hunt et al., 1990). 

Sakurai, T. and Tsuchiya, S. (1988). Superoxide production from non-enzymatically glycated protein. FEES Lett. 236, 406-410. 

Randomized controlled trials of patients with type 2 diabetes have confirmed the beneficial effects of nuts on blood lipids, also seen in nondiabetic subjects, but the trials have not reported improvement in Ale or other glycated proteins (Jenkins and others 2008). Therefore, Jenkins and others (2008) concluded that there is justification to consider the inclusion of nuts in the diets of individuals with diabetes in view of their potential to reduce CHD risk, even though their ability to influence overall glycemic control remains to be established. 

Ahmed MU, Thorpe SR and Baynes JW (1986) Identification of N-car-boxymethyllysine as a degradation product of fructoselysine in glycated protein. J Biol Chem 261, 4889-4894. 

Brownson, C. and Hipkiss, A. R. (2000). Camosine reacts with a glycated protein. Free Radic. Biol. Med. 28,1564-1570. 

H. Watanabe, S. Iwaki, K. Aida, and F. Hayase, Formation and determination of a-dicar-bonyls and an AGE cross-link, pyrropyridine in glycated proteins and in vivo, in G, 2002, 153-156. 

B. S. Szwergold, K. Taylor, S. Lai, B. Su, F. Kappler, and T. R. Brown, Identification of a novel protein kinase activity specific for Amadori adducts on glycated proteins, Diabetes, 1997, 46, 108A. 

N. Yoshida, Y. Sakai, A. Isogai, H. Fukuya, M. Yagi, Y. Tani, and N. Kato, Primary structures of fungal fructosyl amino acid oxidases and their application to the measurement of glycated proteins, Eur. J. Biochem., 1996, 242, 499-505. 

Glycated proteins exhibited a better thermal stability when heated at pH 5 as compared to native or heated control. 

Iyer, U.M. and Mani, LJ.V. (1 990) Studies on the effect of curry leaves supplementation (Murraya koenigii) on lipid profile, glycated proteins and amino acids in non-insulin-dependent diabetic patients. Plant Foods for Human Nutrition (formerly Qualitas Plantarum) 40(4), 275-282. 

ROS produced by sugars and glycated protein autoxidation participate in oxidizing of already glycated proteins and affect other proteins (H24). These reactions are catalyzed by metal ions (W17). The presence of metal ions may, moreover, initiate the Fenton reaction and produce hydroxyl radicals. A carbon-centered 1-hydroxyalkyl radical was found during autoxidation of glyceraldehyde (T12). 

Free radicals generated by glycated proteins initiate lipid peroxidation (H21) and effect nearly twofold increase (over control) of peroxidation of membrane linoleic/arachidonic acid vesicles. This suggests that the increased protein glycation in diabetes accelerates vascular wall lipid oxidative modification (M28). 

D25. Dunn, J. A., Patrick, J. S., Thorpe, S. R., and Baynes, J. W., Oxidation of glycated proteins Age-dependent accumulation of N epsilon-(carboxymethyl)lysine in lens proteins. Biochemistry 28, 9464-9468 (1989). 

Benjamin RJ, Sacks DB. Glycated protein update implications of recent studies, including the diabetes... 

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