How do Fungal Metabolites Influence Epithelial Integrity, Gut Barrier Function, and Nutrient Transport in Livestock? A Protection-Permeability Paradox

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Year : 2026 | Volume : 3 | 02 | Page :
By

Md. Emran Hossain,

  1. Professor, Department of Animal Science and Nutrition, Chattogram Veterinary and Animal Sciences University, Khulshi, Chattogram, Bangladesh

Abstract

The intestinal epithelium represents a dynamic interface between dietary substrates, resident microorganisms, and host tissues, linking barrier integrity with nutrient acquisition and metabolic homeostasis. Fungal metabolites are increasingly recognized as biologically active signals rather than passive components of fermented feeds, yet their effects on the epithelial-nutrient interface remain fragmented across animal nutrition, microbiology, and gut physiology. This review examines how fungal-derived β-glucans, mannans, organic acids, peptides, phenolic derivatives, and other bioactive metabolites influence epithelial integrity, gut barrier function, and nutrient transport in livestock. Particular emphasis is placed on the transition from metabolite exposure to epithelial sensing, intracellular signalling, tight-junction remodeling, mucus dynamics, oxidative homeostasis, and epithelial renewal. We further examine how these processes interact with intestinal microbiota to modify metabolite transformation, microbial cross-feeding, pathogen exclusion, and host-microbe signalling. Beyond barrier protection, the review proposes that fungal metabolites may influence nutrient flux by altering transporter expression, epithelial permeability, absorptive surface characteristics, and the balance between paracellular and transcellular transport. This creates a potential mechanistic link between fungal bioconversion, intestinal resilience, and nutrient-use efficiency. However, responses are highly context-dependent, varying with fungal strain, substrate, metabolite composition, dose, animal species, physiological state, basal diet, microbiome, and environmental stress. Major evidence gaps include inadequate metabolite characterization, limited dose-response information, insufficient distinction between direct fungal effects and microbiota-mediated effects, and reliance on molecular markers without functional measurements of barrier permeability or nutrient flux. We propose a Fungal Metabolite-Barrier Nutrient framework that integrates fungal metabolomics, epithelial biology, microbiome ecology, and nutrient transport. This framework positions fungal metabolites as potential regulators of the gut barrier-nutrient interface and identifies priorities for causal validation, biomarker development, and precision fungal nutrition in sustainable livestock production.

Keywords: gut barrier, intestinal epithelium, fungal metabolites, nutrient transport, livestock nutrition

How to cite this article: Md. Emran Hossain. How do Fungal Metabolites Influence Epithelial Integrity, Gut Barrier Function, and Nutrient Transport in Livestock? A Protection-Permeability Paradox. Emerging Trends in Metabolites. 2026; 03(02):-.
How to cite this URL: Md. Emran Hossain. How do Fungal Metabolites Influence Epithelial Integrity, Gut Barrier Function, and Nutrient Transport in Livestock? A Protection-Permeability Paradox. Emerging Trends in Metabolites. 2026; 03(02):-. Available from: https://journals.stmjournals.com/etm/article=2026/view=260317

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Ahead of Print Subscription Review Article
Volume 03
02
Received 22/09/2026
Accepted 13/10/2026
Published 14/10/2026
Publication Time 22 Days

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