Protein glycation by methylglyoxal is a nonenzymatic post-translational modification whereby arginine and lysine side chains form a chemically heterogeneous group of advanced glycation end-products. Methylglyoxal-derived advanced glycation end-products are involved in pathologies such as diabetes and neurodegenerative diseases of the amyloid type. As methylglyoxal is produced nonenzymatically f...

The causes of insulin resistance are not well-understood in either type 1 or type 2 diabetes. Insulin (INS) is known to undergo rapid non-enzymatic covalent conjugation to glucose or other sugars (glycation). Because the insulin receptor (IR) has INS-like regions associated with both glucose and INS binding, we hypothesize that hyperglycemic conditions may rapidly glycate the IR, chronically in...

Much data support a role for both low density lipoprotein (LDL) oxidation and glycation in atherogenesis. While alpha-tocopherol decreases the oxidative susceptibility of LDL, its role in decreasing LDL glycation is unclear. Hence we tested the effect of alpha-tocopherol both in vitro and in vivo on LDL oxidation and glycation. LDL was isolated after enrichment of plasma with alpha-tocopherol. ...

Glycation is a non-enzymatic reaction between the carbonyl groups of sugars and the amino groups of proteins, nucleic acids and lipids. This process results in the formation of early glycation products, which rearrange to form more stable advanced glycation end products (AGEs). Glycation has been linked to a number of diseases such as, Alzheimer’s, diabetes mellitus, cataract, Parkinson’s, phys...

High glucose concentrations can decrease degradation of mesangium by reducing the activities of matrix metalloproteinases (MMPs). The aim of this study was to investigate the effects of glycation of mesangium matrix on MMP-2, the principal MMP secreted by mesangial cells to degrade type IV collagen. Also examined were membrane type 1 MMP (MT1-MMP), tissue inhibitors of MMPs (TIMP)-1 and -2, and...

Recent studies suggest that advanced glycation endproducts play an important role in cardiovascular complications of ageing, diabetes and end-stage renal failure. Since highly elevated levels of advanced glycation endproducts are present in serum of patients on maintenance haemodialysis, an accurate and rapid assay for their determination would be useful. This would be particularly valuable for...

Human erythrocytes are continuously exposed to glucose, which reacts with the amino terminus of the β-chain of hemoglobin (Hb) to form glycated Hb, HbA1c, levels of which increase with the age of the circulating cell. In contrast to extensive insights into glycation of hemoglobin, little is known about glycation of erythrocyte membrane proteins. In the present study, we explored the conditions ...

BACKGROUND Non-enzymatic glycation is the addition of free carbonyl group of reducing sugar to the free amino groups of proteins, resulting in the formation of a Schiff base and an Amadori product. Dihydroxyacetone (DHA) is one of the carbonyl species which reacts rapidly with the free amino groups of proteins to form advanced glycation end products (AGEs). The highly reactive dihydroxyacetone ...

Nonenzymatic glycation of proteins has been implicated in various diabetic complications and age-related disorders. Proteins undergo glycation at the N-terminus or at the epsilon-amino group of lysine residues. Glycation of proteins proceeds through the stages of Schiff base formation, conversion to ketoamine product and advanced glycation end products. Gramicidin S, which has two ornithine res...