Fucoidan enhances intestinal barrier function by upregulating the expression of claudin-1

Figure 5 Fucoidan prevented the H₂O₂-induced destruction of tight junction protein claudin-1. Caco-2 cells were grown on a Lab-Tek chamber plate. Polarized Caco-2 monolayers were injured by H₂O₂ (500 μmol/L) for 6 h with or without pretreatment of fucoidan (2.5 mg/mL). Immunofluorescence staining for claudin-1 was evaluated using confocal laser scanning microscopy. The data shown are representative and are from 1 of the 3 independent experiments.