Effect of catechin on dietary AGEs absorption and cytotoxicity in Caco-2 cells

Maillard reaction produces advanced glycation end products (AGEs) that endanger human health. This study investigated the protective effect of (+)-catechin (CC) on different types of dietary AGEs absorption and cytotoxicity in Caco-2 cells. Our results showed that CC had higher inhibitory rate on peptide bound-AGEs absorption than free N?-carboxymethyl lysine (CML), which dropped to 36.24% and 32.21% when treated with 20 and 50 ?M CC. The reasons might be that CC could repair the loose tight junction (ZO-1) and down-regulation of proteincoupling peptide carrier 1 (PEPT-1) expression in Caco-2 cells which were in accordance with molecular docking results. Additionally, CC could remarkably decreased the protein levels of receptor of AGEs (RAGE), mitogenactivated protein kinases (MAPK) and nuclear factor-kappa B (NF-?B) that detected by western blotting and immunohistochemical staining method. Taken together, these findings demonstrated that CC may inhibit AGEs absorption and protected Caco-2 cells against RAGE-MAPK-NF-?B signaling suppression.

Automated summary

The study showed that (+)-catechin (CC) inhibited the absorption of peptide bound-AGEs, repaired loose tight junctions (ZO-1) and down-regulated expression of protein-coupling peptide carrier 1 (PEPT-1) in Caco-2 cells. Additionally, CC decreased levels of receptor of AGEs (RAGE), mitogen-activated protein kinases (MAPK) and nuclear factor-kappa B (NF-κB), protecting against RAGE-MAPK-NF-κB signaling suppression.