REGULATION OF THE INTESTINAL INFLAMMATORY RESPONSE THROUGH THE INGESTION OF MAILLARD COMPOUNDS AND THEIR INTERACTION WITH RAGE AND GPR43 RECEPTORS

Abstract

Molecular damage signals attract neutrophils to sites of infection or inflammation. The G-protein coupled receptor (GPR43) and the receptor for advanced glicosilation compounds (RAGE) recognize short-chain fatty acids (propionate and butyrate) and AGEs (advanced glycosylation compounds) respectively, both receptors being abundantly expressed in neutrophils and intestinal epithelial cells. The functional role that activation of these receptors plays in the in vivo orchestration of the immune response is unclear. Our work examines the effect of the ingestion of AGEs on the immune response, both in healthy mice and in mice that were induced to colitis, using transgenic mice deficient in GPR43 or RAGE receptors. One of the main findings is that both the GPR43 receptor and RAGE are necessary for the recruitment of neutrophils in a model of intestinal inflammation due to mucosal barrier injury. We have also verified that the AGEs ingested with the diet promote the appearance of an imbalance in the inflammatory balance at the intestinal level, giving rise to a pro-inflammatory status. We have also show that carboxymethylisine (CML), a specific type of AGE, is capable of stimulating the GPR43 receptor and acting as a neutrophil chemoattraction factor. Finally, we have tested the treatment with sRAGE, a protein capable of capturing free AGEs. This procedure could be a promising therapy for the treatment of inflammatory bowel disease.