Bi-directional interactions between the gut microbiota and dietary glycation products

Abstract

Advanced glycation end products (AGEs) and their precursors are a heterogenous group of compounds being associated with adverse health effects. AGEs can be formed endogenously and in exogenous sources including food. This review investigates the roles of endogenously versus exogenously formed AGEs in the potential induction of adverse health effects, focusing on differences in toxicokinetics and toxicodynamics of low molecular mass (LMM), high molecular mass (HMM) AGEs and their (dicarbonyl) precursors. Based on the available data, exogenous LMM AGEs seem to be bioavailable and together with their precursors they may contribute to dicarbonyl stress and protein cross linking resulting in formation of endogenous AGEs. Bioavailability of exogenous HMM AGEs and precursors appears limited, while these can bind to the AGE receptor (RAGE), initiating adverse health effects. Together, this suggests that adverse health effects via RAGE-binding in relevant tissues will more likely result from endogenously formed AGEs. Effects on gut microbiota composition and functionality induced by AGEs and their precursors is proposed as a third mode of action. Overall, there is a need for studies which better discriminate between free and peptide or protein-bound AGEs and their precursors in order to enable further elucidation of the contributions of these different types of glycation products to the ultimate biological effects.