Effect of resveratrol combined with 5-aminosalicylic acid on tight junction protein expression in lipopolysaccharide-induced HT-29 cells

Objective: To explore the effect and mechanism of resveratrol(RSV)combined with 5-aminosalicylic acid (5-ASA) on tight junction protein expression in lipopolysaccharide (LPS)-induced HT-29 cells.Methods: Human colorectal adenocarcinoma cells HT-29 were stimulated with 100 μg/mL LPS and divided into LPS group, 5-ASA group, RSV group, RSV+5-ASA group, and control group.Cell viability was determined by CCK-8 method.The protein expressions of occludin, claudin-1, ZO-1, Notch1 and Hes1 were detected by western blotting.Transmission electron microscopy (TEM) was used to observe the tight junction structure of cells.Results: Compared with the control group, the protein expressions of tight junction proteins occludin, claudin-1 and ZO-1 decreased in LPS group, while the protein expressions of Notch1 and Hes1 increased (all P＜0.05), and the tight junction structure was blurred, presenting continuity interruption.Compared with LPS group, the expressions of tight junction proteins occludin, claudin-1 and ZO-1 in 5-ASA group, RSV group and RSV+5-ASA group were up-regulated, the protein expressions of Notch1 and Hes1 were down-regulated (all P＜0.05), and the tight junction structure was dense.RSV+5-ASA group was the most significant (P＜0.05).Conclusion: RSV combined with 5-ASA can up-regulate the expressions of tight junction proteins occludin, claudin-1 and ZO-1 in HT-29 cell injury model, which may be related to the inhibition of Notch1 signaling pathway activity.