Studies in vitro of equine intestinal glucagon-like peptide-2 secretion.

Authors: Sibthorpe P E M, Fitzgerald D M, Sillence M N, de Laat M A

Journal: Journal of equine veterinary science

DOI: 10.1016/j.jevs.2024.105179 PubMed: 39197558Log in to save

Summary

# Editorial Summary Insulin dysregulation in horses represents a significant clinical concern due to the hyperinsulinaemia-laminitis link, yet the contribution of gastrointestinal hormones to this condition remains poorly characterised in equines compared to other species. Using post-mortem small intestinal tissue samples, Sibthorpe and colleagues conducted an in vitro investigation of glucagon-like peptide-2 (GLP-2) secretion from L cells across three duodenal regions: duodenum, jejunum, and ileum. The jejunum and ileum secreted 5–9-fold more GLP-2 basally than the duodenum (P < 0.05), with only jejunal tissue demonstrating glucose-responsive secretion; this glucose-stimulated response was suppressed by 30% with selective SGLT-1 inhibition and 38% with non-selective SGLT-1/GLUT-2 inhibition (both P ≤ 0.05). These findings suggest that glucose-sensing L cells concentrated in the jejunum may play a mechanistic role in post-prandial hyperinsulinaemia development, establishing essential physiological parameters that will support future studies investigating whether GLP-2 dysregulation contributes to insulin dysregulation in horses—knowledge that could ultimately inform dietary and therapeutic strategies for affected animals.

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Practical Takeaways

•Jejunal glucose absorption and GLP-2 secretion may contribute to post-prandial hyperinsulinaemia in horses with insulin dysregulation; dietary strategies targeting jejunal glucose handling warrant investigation
•This foundational work on equine intestinal GLP-2 physiology opens potential therapeutic avenues for managing insulin dysregulation and laminitis prevention through intestinal hormone modulation
•Further research may eventually enable targeted nutritional or pharmacological interventions at the jejunum to reduce hyperinsulinaemia risk in susceptible horses

Key Findings

•GLP-2 secretion was 5-9 fold higher in jejunum and ileum compared to duodenum (P < 0.05)
•Glucose stimulation increased GLP-2 secretion only in jejunum, not in ileum or duodenum
•SGLT-1 inhibitor phlorizin reduced glucose-stimulated GLP-2 secretion in jejunum by 30% (P = 0.02)
•Non-selective SGLT-1/GLUT-2 inhibitor phloretin reduced glucose-stimulated GLP-2 secretion in jejunum by 38% (P = 0.04)

Conditions Studied

insulin dysregulationhyperinsulinaemialaminitis

Related References

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