Improvement of the intestinal epithelial barrier during laxative effects of phlorotannin in loperamide-induced constipation of SD rats

• Published in: Laboratory animal research Vol. 39; no. 1; p. 1
• Main Authors: Kim, Ji Eun, Song, Hee Jin, Choi, Yun Ju, Jin, You Jeong, Roh, Yu Jeong, Seol, Ayun, Park, So Hae, Park, Ju Min, Kang, Hyun Gu, Hwang, Dae Youn
• Format: Journal Article
• Language: English
• Published: England BioMed Central 03.01.2023; BMC; 한국실험동물학회
• Subjects: Adherens junction; Colon; Constipation; Digestive system diseases; E-cadherin; Epithelial cells; Feces; Histology; Inflammatory bowel disease; Inflammatory bowel diseases; Interleukin 13; Interleukin 4; Interleukin 6; Intestinal epithelial barrier; Intestine; Irritable bowel syndrome; Lamina propria; Laxative effects; Laxatives; Osmosis; Permeability; Phenotypes; Phlorotannins; Proteins; Regulatory proteins; Standard deviation; Tight junction; Tumor necrosis factor-α; Zonula occludens-1 protein; 수의학; Tight junction; Constipation; Intestinal epithelial barrier; Laxative effects; Phlorotannins; Adherens junction
• ISSN: 1738-6055; 2233-7660; 2233-7660
• DOI: 10.1186/s42826-022-00152-1

Disruptions of the intestinal epithelial barrier (IEB) are frequently observed in various digestive diseases, including irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). This study assessed the improvement in the IEB during the laxative activity of phlorotannin (Pt) harvested from Ecklonia cava in constipation by examining the changes in the expression of the regulatory proteins for the tight junction (TJ) and adherens junction (AJ), and inflammatory cytokines in Sprague Dawley (SD) rats with loperamide (Lm)-induced constipation after a Pt treatment. The Pt treatment induced laxative activity, including the improvement of feces-related parameters, gastrointestinal transit rate, and histological structure of the mid colon in Lm-treated SD rats. In addition, significant recovery effects were detected in the histology of IEB, including the mucus layer, epithelial cells, and lamina propria in the mid colon of Lm + Pt treated SD rats. The expression levels of E-cadherin and p120-catenin for AJ and the ZO-1, occludin, and Claudin-1 genes for TJ in epithelial cells were improved remarkably after the Pt treatment, but the rate of increase was different. Furthermore, the Pt treatment increased the expression level of several inflammatory cytokines, such as TNF-α, IL-6, IL-1β, IL-13, and IL-4 in Lm + Pt treated SD rats. These results provide the first evidence that the laxative activity of Pt in SD rats with Lm-induced constipation phenotypes involve improvements in the IEB.