Protein–phenolic interactions and inhibition of glycation – combining a systematic review and experimental models for enhanced physiological relevance

Vlassopoulos, A., Lean, M.E.J. and Combet, E. (2014) Protein–phenolic interactions and inhibition of glycation – combining a systematic review and experimental models for enhanced physiological relevance. Food and Function, 5(10), pp. 2646-2655. (doi: 10.1039/C4FO00568F)

Abstract

Background: While antiglycative capacity has been attributed to (poly)phenols, the exact mechanism of action remains unclear. Studies so far are often relying on supra-physiological concentrations and use of non-bioavailable compounds.<p></p> Methods: To inform the design of a physiologically relevant in-vitro study, we carried out a systematic literature review of dietary interventions reporting plasma concentrations polyphenol metabolites. Bovine Serum Albumin (BSA) was pre-treated prior to in vitro glycation: either no treatment (native), pre-oxidised (incubated with 10nM H2O2, for 8 hours) or incubated with a mixture of phenolic acids at physiologically relevant concentrations, for 8 hours). In-vitro glycation was carried out in presence of i) glucose only (0, 5 or 10mM), ii) glucose (0, 5 or 10mM) plus H2O2 (10nM), or iii) glucose (0, 5 or 10mM) plus phenolic acids (10-160nM). Fructosamine was measured using the nitroblue tetrazolium method.<p></p> Results: Following (high) dietary polyphenol intake, 3-hydroxyphenylacetic acid is the most abundant phenolic acid in peripheral blood (up to 338μM) with concentrations for other phenolic acids ranging from 13nM-200μM. Presence of six phenolic acids with BSA during in-vitro glycation did not lower fructosamine formation. However, when BSA was pre-incubated with phenolic acids, significantly lower concentration of fructosamine was detected under glycoxidative conditions (glucose 5 or 10mM plus H2O2 10nM) (p<0.001 vs. native BSA).<p></p> Conclusion: Protein pre-treatment, either with oxidants or phenolic acids, is an important regulator of subsequent glycation in a physiologically relevant system. High quality in-vitro studies under conditions closer to physiology are feasible and should be employed more frequently.<p></p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lean, Professor Michael and Vlassopoulos, Dr Antonis and Combet Aspray, Professor Emilie
• Authors: Vlassopoulos, A., Lean, M.E.J., and Combet, E.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: Food and Function
• Publisher: Royal Society of Chemistry
• ISSN: 2042-6496
• ISSN (Online): 2042-650X
• Copyright Holders: Copyright © 2014 The Authors
• First Published: First published in Food and Function 5(10):2646-2655
• Publisher Policy: Reproduced under a Creative Commons License