Journal Article

In Vitro Investigation of Equine Gut Microbiota Alterations During Hypoglycin A Exposure

Scippo, Marie-Louise, Massey, Claire, Douny, Caroline, Hyde, Carolyn, Renaud, Benoît, Gustin, Pascal, Votion, Dominique-Marie, François, Anne-Christine, Daube, Georges, Taminiau, Bernard, Gonza-Quito, Irma Elizabeth, Piercy, Richard J., Delcenserie, Véronique

2025

Overview

Hypoglycin A is a plant-derived protoxin that causes atypical myopathy in equids. In atypical myopathy-affected horses, metabolomic and microbiome studies have reported alterations in metabolic markers and faecal microbiota composition, pointing to a potential disruption of microbial homeostasis. However, in vivo observations are strongly confounded by host-related factors, underscoring the need for controlled in vitro approaches. To address this, we used an in vitro static batch fermentation model simulating the equine colon to investigate the direct effects of hypoglycin A on microbiota composition and activity. Faecal inocula from healthy horses were incubated in control and hypoglycin A-treated fermenters for 48 h, with serial analyses of hypoglycin A concentration, short-chain fatty acids, and 16S rRNA gene profiles. Hypoglycin A remained stable in the nutritive medium in the absence of microbiota, confirming that its degradation in inoculated fermenters was microbiota-dependent. The results showed significant microbial-associated hypoglycin A degradation without evidence of toxic metabolite formation. The analysis of α- and β-diversity revealed both an effect of incubation time, reflecting the natural temporal dynamics of microbial communities under batch fermentation, and a specific impact of hypoglycin A exposure, with certain taxa such as Paraclostridium being affected. This study provides the first in vitro evidence that the equine microbiota contributes to hypoglycin A degradation.

• Publisher: MDPI AG,Multidisciplinary Digital Publishing Institute (MDPI)
• Subject: 16S rRNA gene sequencing / Acer / Acer pseudoplatanus / Acylcarnitines / Amino acids / Animal Science and Zoology / Animals / Atypical myopathy / Blood metabolites / Chevaux / Colon / Equine / equine atypical myopathy / Faecal microbiome / Faecal microbiota / Feeds / Fermentation / Gut microbiota / Horses / hypoglycin A / Hypoglycine A / Hypotheses / in vitro batch fermentation / intestinal microbiota / Intoxication / Investigations / Life sciences / Maple / Metabolites / methylenecyclopropylacetyl-carnitine / Microbiome / Microbiome fécal / microbiota / Microbiota (Symbiotic organisms) / Microbiote fécal / Microbiote intestinal / Myopathie atypique / Médecine vétérinaire & santé animale / Métabolites sanguins / next generation sequencing / NGS / Pasture / Poisoning / Prevention / Prévention / Pâture / Ruminants / Sciences du vivant / short chain fatty acids / Toxicity / Toxicologie / Toxicology / toxin / Toxine / Veterinary (all) / Veterinary medicine & animal health / Équins / Érable