Nonenzymatic glycation

MaillardReaction (Nonenzymatic Glycation), Browned reaction products ate formed by heating amino acid and simple sugar. This reaction is important in food science relating to coloring, taste, and flavor enhancement (79), and is iUustrated as follows ... 

Atherosclerotic lesions are thought to arise from transport and retention of plasma LDL through the endothelial cell layer into the extracellular matrix of the subendothelial space. Once in the artery wall, LDL is chemically modified through oxidation and nonenzymatic glycation. Mildly oxidized LDL then recruits monocytes into the artery wall. These monocytes then become transformed into macrophages that accelerate LDL oxidation. 

Another form of post-transitional modification that may add carbohydrate to a polypeptide is nonenzymatic glycation. This reaction occurs between the reducing ends of sugar molecules and the amino groups of proteins and peptides. See Section 2.1 for further details and the reaction sequence behind this modification. 

B. S. Szwergold, S. K. Howell, and P. J. Beisswenger, Nonenzymatic glycation/enzy-matic deglycation A novel hypothesis on the etiology of diabetic complications, in G, 2002, 143-152. 

Figure 32-1. (A) Schematic representation of the nonenzymatic glycation of proteins, including hemoglobin, resulting in glycated HbAlc. (B) Chemical structure of advanced glycation end products in tissues exposed to chronic hyperglycemia.The R groups designate tissue proteins that have become cross-linked and frequently become dysfunctional as a result of this process. Adapted from Brownlee (1992).

SI. Sakurai, T., and Tsuchiya, S., Superoxide production from nonenzymatically glycated protein. FEBS Lett. 236, 406-410 (1988). 

Reiser KM, Amigable MA, Last JA (1992) Nonenzymatic glycation of the type I collagen. J Biol Chem 267 24207-24216. 

G5. Garlick, R. L., Bunn, H. F., and Spiro, R. T., Nonenzymatic glycation of basement membranes from human glomeruli and bovine sources Effect of diabetes and age. Diabetes 37,1144-1150 (1988). 

The Maillard reaction, also referred to as nonenzymatic glycation or browning, was characterized in 1912. He observed that yellow-brown colors were produced when glucose was heated with glycine. He repeated the experiment with many different reducing sugars and amino acids [1]. 

Zhang, Q.B. Tang, N. Brock, J.W.C. Mottaz, H.M. Ames, J.M. Baynes, J.W. Smith, R.D. Metz, TO. Enrichment and analysis of nonenzymatically glycated peptides Boronate affinity chromatography coupled with electron-transfer dissociation mass spectrometry. J. Proteome Res. 2007, 6, 2323-2330. 

J.N. Lyang and L.T. Chylack Jr., Spectroscopic study on the effects of nonenzymatic glycation in... 

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