Accumulation and effects of dietary advanced glycation end products on the gastrointestinal tract in rats

Abstract

Summary The gastrointestinal ( GI ) tract represents the first barrier against the penetration of organisms by dietary advanced glycation end products ( AGE s), but the tissue accumulation of AGE s and AGE ‐induced effects on the GI tract have yet to be completely elucidated. This study aimed to investigate the tissue accumulation of AGE s and AGE ‐induced oxidative stress and inflammation in the GI tract of rats after long‐term consumption of AGE s from bread crust ( BC ). The GI tract was then removed to analyse carboxymethyllysine ( CML ) and malondialdehyde ( MDA ) contents, the activities of superoxide dismutase ( SOD ) and glutathione peroxidase ( GSH ‐Px) and the levels of tumour necrosis factor‐α ( TNF ‐α) and interleukin‐6 ( IL ‐6). This study demonstrates that the oral intake of AGE s promotes their accumulation in the GI tract, and AGE s attenuate the first‐line antioxidant defence and stimulate the inflammatory response of the GI tract by downregulating enzymatic antioxidative pathways and increasing inflammatory cytokine levels.