Enhanced Intestinal Barriers by Puerarin in Combination with Tryptophan

Abstract

The intestinal barrier is essential for maintaining human intestinal health. The growing number of studies has shown that both puerarin and tryptophan and its metabolites have a beneficial effect on the intestinal barrier. This study aims at the combination of puerarin and tryptophan or its metabolites for improving the intestinal barrier. In our study, 40 female Sprague− Dawley rats were randomly divided into five groups (n = 8) for a 4-week experiment and dextran sodium sulfate was used to induce an intestinal barrier injury in rats. Our results showed that puerarin combined with tryptophan or its metabolites (indole-3-propionic acid, IPA) improved the intestinal barrier by enhancing the mucus layer barrier, which was mainly achieved by increasing the number of goblet cells and promoting the secretion of MUC2. Both TRPM5 and VAMP8 promoted MUC2 secretion in goblet cells through exocytosis, but their mechanisms of action are different. In our study, we found that puerarin and tryptophan showed different effects on TRPM5 and VAMP8, respectively. Puerarin enhances the expression of TRPM5, and tryptophan inhibits the expression of TRPM5; however, puerarin and tryptophan have no significant effect on the expression of VAMP8.

Effects of Dietary Indole-3-carboxaldehyde Supplementation on Growth Performance, Intestinal Epithelial Function, and Intestinal Microbial Composition in Weaned Piglets

“…Indole strengthened epithelial cell barrier properties by increasing tight junction resistance, and attenuated indicators of inflammation ( 6 ). Indole-3-propionic acid decreased FITC-dextran-dependent gut permeability in mice ( 22 – 24 ), increased mucin secretion in human colonic cells ( 9 ), increased goblet cell numbers and mucosa thickness in rats ( 25 ), and acted as a ligand of the aryl hydrocarbon receptor (AhR) and exerted an anti-inflammatory effect in colon ( 26 ). In this study, dietary ICA supplementation in weaned piglets did not alter intestinal morphological characteristics including the villus height, crypt depth, and villus height/crypt depth ratio, and had no influence on intestinal permeability as reflected by DAO, D-lactic acid and endotoxin concentration.…”

Biological Effects of Indole-3-Propionic Acid, a Gut Microbiota-Derived Metabolite, and Its Precursor Tryptophan in Mammals’ Health and Disease

“…Studies on the GBB demonstrate that indole [10] and IPA [20,116,117], two tryptophan metabolites, improve barrier properties by increasing the expression of claudins and other tight junction proteins. Additionally, IPA increases secretion of mucins in in vitro human colonic culture [20] and increases the number of goblet cells and mucosa thickness in rats [118]. Moreover, IPA acts as a ligand of the aryl hydrocarbon receptor (AhR) present in colonic epithelial cells, activation of which is associated with anti-inflammatory and anticancer effects [119] Interestingly, it has been observed that in patients suffering from colitis serum, IPA concentration decreases significantly [28].…”

Ameliorating effects of Hericium erinaceus polysaccharides on intestinal barrier injury in immunocompromised mice induced by cyclophosphamide

“…1 The destruction of the intestinal mucosal barrier increases intestinal permeability, which leads to harmful substances passing through intestinal epithelial cells and entering circulation, mediating the chronic inflammatory state of the whole body, 2 including inflammatory bowel disease, alcoholic and nonalcoholic liver diseases, and food allergies. 3,4 Therefore, the integrity of the intestinal barrier plays an important role in the physiological regulation of human beings. 5 To date, research on the intestinal barrier has been a hot topic in food science and clinical medicine.…”