Protein Glycation: A Firm Link to Cause Metabolic Disease and their Complications

Abstract

Glycation of proteins starts with the formation of Schiff base, followed by intermolecular rearrangement and conversion into Amadori products. When large amounts of Amadori products are formed, they undergo cross linkage to form a heterogeneous group of protein-bound moieties, termed as Advanced Glycation End products (AGEs). The formation of AGEs is irreversible process, causing structural and functional changes in protein. This results in generation of free radicals which play an important role in pathophysiology of ageing and diabetes. The rates of these reactions are quite slow and proteins with large amounts of lysine residues undergo glycation with significant amounts of AGEs. The unwanted consequences of protein glycation may lead to several metabolic disorders like diabetes, arteriosclerosis, osteoporosis and Alzheimer's disease etc. and their complications. This commentary reviews the glycation of proteins which have already been demonstrated by us and others.

Therapeutic Efficacy of Natural Product ‘C-Phycocyanin’ in Alleviating Streptozotocin-Induced Diabetes via the Inhibition of Glycation Reaction in Rats

“…In diabetes, consistent high glucose levels may induce glycation, which leads to advanced glycation end product (AGE) formation and, consequently, generates various diabetic problems [6]. Glycation is a nonenzymatic process that occurs when a reducing sugar's carbonyl group reacts with nucleic acids, lipids, and the amino group of proteins [7,8]. Albumin, fibrinogen, and globulin are plasma proteins that can be modified nonenzymatically, and these modifications can have numerous negative effects, including altered drug affinity in the plasma, platelet activation, the production of oxygen free radicals, impaired fibrinolysis, and immune system modulation [9,10].…”