Equine metabolic syndrome: Role of the enteroinsular axis in the insulin response to oral carbohydrate.
Authors: de Laat Melody A, Fitzgerald Danielle M
Journal: Veterinary journal (London, England : 1997)
Summary
Insulin dysregulation in horses—characterised by exaggerated insulin responses to oral carbohydrates, true insulin resistance, or both—remains a significant clinical concern because of its established link to laminitis development. De Laat and Fitzgerald's 2023 review examines the enteroinsular axis (the gastrointestinal signalling system that regulates pancreatic insulin secretion) as a potential contributor to this condition, drawing on emerging equine research alongside extensive evidence from other species. Whilst incretin peptides such as glucagon-like peptide-1 and -2 have been investigated in horses, many functionally important EIA components—including glicentin and oxyntomodulin—remain essentially unexplored in this species, despite clear roles in enhancing post-meal insulin secretion. The authors highlight critical knowledge gaps between equine-specific findings and what is understood in humans and rodents, suggesting that a more complete characterisation of the enteroinsular axis would improve our ability to diagnose and manage insulin dysregulation. For practitioners involved in metabolic assessment, nutritional management and laminitis prevention, this review underscores that oral carbohydrate testing protocols warrant continued refinement and that our current understanding of the mechanisms driving post-prandial hyperinsulinaemia in horses remains incomplete.
Read the full abstract on PubMed
Practical Takeaways
- •Oral carbohydrate testing that includes gastrointestinal assessment is important for diagnosing insulin dysregulation and identifying laminitis risk in horses, particularly measuring post-prandial insulin responses.
- •Understanding how the gastrointestinal tract enhances insulin secretion through the enteroinsular axis can help inform dietary management strategies to reduce hyperinsulinaemia and laminitis risk.
- •Current knowledge gaps remain regarding several gut peptides in horses; ongoing research into enteroinsular axis function may reveal new diagnostic or therapeutic targets for managing insulin dysregulation.
Key Findings
- •Post-prandial hyperinsulinaemia is the more commonly identified component of equine insulin dysregulation and is diagnosed using tests that assess the gastrointestinal tract.
- •Key enteroinsular axis components including glucagon-like peptide-1 and glucagon-like peptide-2 have been investigated in horses and increase insulin responses to oral carbohydrate through one or more mechanisms.
- •Many enteroinsular axis peptides such as glicentin and oxyntomodulin remain unexplored in equine species despite their potential importance.
- •Hyperinsulinaemia in horses has a clear association with laminitis risk, justifying the need for better understanding of insulin and glucose homeostasis.