title: Inhibitory effect of metformin and pyridoxamine in the formation of early, intermediate and advanced glycation end-products.
abstract: 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 phosphate is a derivative of dihydroxyacetone (DHA), and a product of glycolysis, having potential glycating effects to form AGEs. The formation of AGEs results in the generation of free radicals which play an important role in the pathophysiology of aging and diabetic complications. While the formation of DHA-AGEs has been demonstrated previously, no extensive studies have been performed to assess the inhibition of AGE inhibitors at all the three stages of glycation (early, intermediate and late) using metformin (MF) and pyridoxamine (PM) as a novel inhibitor.
  
  
  RESULTS
  In this study we report glycation of human serum albumin (HSA) & its characterization by various spectroscopic techniques. Furthermore, inhibition of glycation products at all the stages of glycation was also studied. Spectroscopic analysis suggests structural perturbations in the HSA as a result of modification which might be due to generation of free radicals and formation of AGEs.
  
  
  CONCLUSIONS
  The inhibition in the formation of glycation reaction reveals that Pyridoxamine is a better antiglycating agent than Metformin at all stages of the glycation (early, intermediate and late stages).
authors.affiliation: Department of Biotechnology, Integral University, Lucknow, India.
authors.forename: Saheem
authors.initials: S
authors.lastname: Ahmad
authors.forename: Uzma
authors.initials: U
authors.lastname: Shahab
authors.forename: Mohd Hassan
authors.initials: MH
authors.lastname: Baig
authors.forename: Mohd Sajid
authors.initials: MS
authors.lastname: Khan
authors.forename: M Salman
authors.initials: MS
authors.lastname: Khan
authors.forename: A K
authors.initials: AK
authors.lastname: Srivastava
authors.forename: Mohd
authors.initials: M
authors.lastname: Saeed
authors.lastname: Moinuddin
mesh_terms: D017127:Glycation End Products, Advanced / Q000378:metabolism*; D006031:Glycosylation / Q000187:drug effects; D006801:Humans; D008687:Metformin / Q000494:pharmacology*; D011733:Pyridoxamine / Q000494:pharmacology*
chemical_list: D017127:Glycation End Products, Advanced; D011733:Pyridoxamine; D008687:Metformin
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