Long Noncoding RNA H19 Impairs the Intestinal Barrier by Suppressing Autophagy and Lowering Paneth and Goblet Cell Function

Abstract Background & Aims The protective intestinal mucosal barrier consists of multiple elements including mucus and epithelial layers, and immune defense; nonetheless, barrier dysfunction is common in various disorders. The imprinted and developmentally regulated long noncoding RNA (lncRNA) H19 is involved in many cell processes and diseases. Here, we investigated the role of H19 in regulating Paneth and Goblet cells, and autophagy and its impact on intestinal barrier dysfunction induced by septic stress. Methods Studies were conducted in H19-deficient (H19-/-) mice, mucosal tissues from patients with sepsis, primary enterocytes, and Caco-2 cells. Septic stress was induced by cecal ligation and puncture (CLP), and gut permeability was detected by tracer FITC-dextran assays. The function of Paneth and Goblet cells was examined by immunostaining for lysozyme and mucin 2, respectively, and autophagy was examined by LC3-II immunostaining and Western blotting analysis. Intestinal organoids were isolated from H19-/- and control littermate mice and treated with lipopolysaccharide (LPS). Results Intestinal mucosal tissues in mice 24 h after exposure to CLP and in patients with sepsis displayed high H19 levels, associated with intestinal barrier dysfunction. Targeted deletion of the H19 gene in mice enhanced the function of Paneth and Goblet cells and promoted autophagy in the small intestinal mucosa. Knockout of H19 protected Paneth and Goblet cells against septic stress, preserved autophagy activation, and promoted gut barrier function after exposure to CLP. Compared with organoids from control littermate mice, intestinal organoids isolated from H19-/- mice had increased numbers of lysozyme- and mucin 2-positive cells and exhibited increased tolerance to LPS. Conversely, ectopic overexpression of H19 in cultured IECs prevented rapamycin-induced autophagy and abolished the rapamycin-induced protection of the epithelial barrier against LPS. Conclusions In investigations of mice, human tissues, primary organoids, and IECs, we found that elevated H19 inhibited the function of Paneth and Goblet cells and suppressed autophagy, thus potentially contributing to barrier dysfunction in intestinal pathologies.