TNF-α-Induced miR-21-3p Promotes Intestinal Barrier Dysfunction by Inhibiting MTDH Expression

Front Pharmacol. 2021 Aug 12:12:722283. doi: 10.3389/fphar.2021.722283. eCollection 2021.

Abstract

Intestinal barrier dysfunction is characterized by increased intestinal permeability to lumen endotoxin, showing remarkable predisposition to immune enteropathy, and colorectal cancer tumor necrosis factor (TNF)-α is associated with this pathological process, while the mechanism remains unknown. In this study, different doses of TNF-α were used for Caco-2 cell treatment. We discovered that miR-21-3p expression was obviously increased by TNF-α in a dose-dependent manner. Further study demonstrated that TNF-α could upregulate miR-21-3p expression through the NF-κB signaling pathway. Then, TargetScan and miRWalk miRNA-mRNA interaction prediction online tools were introduced, and metadherin (MTDH) was screened out as a potential target of miR-21-3p. We subsequently found that miR-21-3p could directly target the 3'-untranslated region (UTR) of MTDH mRNA and inhibit its expression. Furthermore, it was demonstrated that miR-21-3p could regulate the Wnt signaling pathway by targeting MTDH mRNA, suggesting the effect of miR-21-3p/MTDH/Wnt axis on intestinal barrier dysfunction. Our findings provide a novel potential biomarker and therapeutic target for intestinal barrier dysfunction and related diseases.

Keywords: MTDH; TNF-α; Wnt signaling pathway; intestinal barrier dysfunction; miR-21-3p.