Related Experiment Video
Updated: May 9, 2026
Analyzing Beneficial Effects of Nutritional Supplements on Intestinal Epithelial Barrier Functions During Experimental Colitis
Published on: January 5, 2017
Lactobacillus-derived indole derivatives ameliorate intestinal barrier damage in rat pups with complementary food
Arong Wang1,2, Cheng Guan1,2, Tieqi Wang1,2
1School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China. GuangqingMu@163.com.
Insights
Complementary foods can harm infant gut health. Supplementing with L-tryptophan and specific Lactobacillus strains (S164 or M94) restored intestinal barrier function and gut microbiota in rat pups.
Area of Science:
- Microbiology
- Gastroenterology
- Immunology
Background:
- Complementary foods can induce diarrhea and intestinal barrier dysfunction in infants.
- Infant gut health is crucial for overall development and immunity.
Purpose of the Study:
- To investigate the efficacy of L-tryptophan (Trp) combined with specific Lactobacillus strains in ameliorating complementary food-induced intestinal damage in rat pups.
- To elucidate the underlying mechanisms involving gut microbiota modulation and molecular pathways.
Main Methods:
- Rat pups were fed complementary foods, followed by oral administration of Trp combined with *Lactiplantibacillus plantarum* DPUL-S164 or *Limosilactobacillus reuteri* DPUL-M94.
- Histopathological analysis of colon tissues, measurement of pro-inflammatory cytokines, gene expression analysis (cell differentiation, tight junctions), and gut microbiota profiling were performed.
Main Results:
- Trp combined with S164 or M94 significantly restored colon tissue pathology and reduced pro-inflammatory cytokine expression.
- The intervention promoted cell differentiation and tight junction protein expression by activating the aryl hydrocarbon receptor (AhR) and nuclear factor erythroid 2-related factor 2 (Nrf2) pathways.
- Increased levels of indole-3-lactic acid (ILA), indole-3-propionic acid (IPA), and indole-3-carbaldehyde (I3C) were observed, alongside an enhanced abundance of *Lactobacillus* and *Akkermansia* species.
Conclusions:
- Oral administration of Trp with *Lactiplantibacillus plantarum* DPUL-S164 or *Limosilactobacillus reuteri* DPUL-M94 effectively ameliorates complementary food-induced intestinal barrier damage and gut dysbiosis in rat pups.
- The protective effects are mediated by the production of indole derivatives (ILA, IPA, I3C) acting as AhR ligands, leading to the restoration of intestinal barrier integrity and modulation of gut microbiota composition.
Abstract:
The consumption of complementary foods can bring about diarrhea and intestinal barrier dysfunction in infants. In this study, three different Lactobacillus strains combined with L-tryptophan (Trp) were administered to rat pups with complementary foods. Complementary food feeding caused inflammatory cell infiltration, crypt structure irregularity and goblet cell reduction in the colon tissues of the rat pups. However, the oral administration of Trp combined with Lactiplantibacillus plantarum DPUL-S164 or Limosilactobacillus reuteri DPUL-M94 significantly restored the pathological changes in the colon tissues and inhibited the expression of pro-inflammatory cytokines in the colon and ileum of the rat pups. M94 or S164 combined with Trp intervention could promote the expression of cell differentiation genes and tight junction proteins, and restore the intestinal barrier damage caused by complementary foods in rat pups by activating the aryl hydrocarbon receptors (AhR) and nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. In addition, the indole-3-lactic acid (ILA), indole-3-propionic acid (IPA), or indole-3-carbaldehyde (I3C) level in the cecal contents of the rat pups increased after intervention of Trp combined with S164 or M94, which may account for the amelioration of intestinal barrier damage in rat pups administered with complementary foods. Furthermore, S164 or M94 combined with Trp intervention up-regulated the relative abundance of f_Lactobacillaceae, f_Akkermansiaceae, g_Lactobacillus, and g_Akkermansia in the intestinal tract of the rat pups. In conclusion, S164 or M94 combined with Trp intervention can ameliorate complementary food-induced intestinal barrier damage and gut flora disorder in rat pups by producing ILA, IPA, or I3C, which are AhR ligands.
