GLP-2 Slows Gut Contractions Partly by Releasing VIP in the Intestinal Wall | Research

The takeaway

GLP-2 suppresses gut muscle contractions in mouse ileum partly through VIP-mediated nerve signaling, providing the first evidence of this mechanism in isolated intestinal tissue.

First evidence
This study provides the first direct demonstration that VIP contributes to GLP-2's inhibitory effects on neurally evoked contractions in isolated intestinal tissue.

What the researchers found

VIP antagonist (VIP 6-28) reduced GLP-2's inhibitory effect on neurally evoked ileal contractions, and GLP-2 exposure decreased VIP-positive nerve fibers in muscle layers — first evidence of VIP-mediated GLP-2 action in isolated gut tissue.

Why it matters

GLP-2 analogs like teduglutide are used to treat short bowel syndrome. Understanding exactly how GLP-2 modulates gut motility — through VIP and nerve pathways — could help predict and manage motility side effects and potentially lead to more targeted gut-specific therapies.

How the study worked

Ex vivo study using isolated mouse ileal segments with functional contraction measurements (spontaneous and electrically evoked) plus immunohistochemistry for VIP in nerve fibers after GLP-2 exposure.

What this study cannot tell us

This is an ex vivo mouse study — results from isolated ileal preparations may not fully reflect in vivo gut physiology. Only the ileum was tested; other gut segments may respond differently. The study cannot determine whether this mechanism is significant at physiological GLP-2 concentrations in living animals or humans.

How to read the evidence

This is a mechanistic ex vivo study in mouse tissue. It provides novel insight into GLP-2/VIP interaction but is preliminary and limited to isolated tissue preparations.

When this study was published

Published in 2025, advancing basic understanding of GLP-2 gut pharmacology.

The bigger picture

The GLP-2 pathway is less discussed than GLP-1 but is therapeutically important for intestinal adaptation and nutrient absorption. This study reveals that GLP-2's gut-relaxing effect involves the VIP neuropeptide system, adding to our understanding of how incretin hormones regulate gut function through enteric nervous system crosstalk.

Questions still open

Does this VIP-mediated mechanism contribute to the gastrointestinal side effects of teduglutide therapy?
Is the GLP-2/VIP interaction present throughout the entire intestine or specific to the ileum?
Could targeting VIP alongside GLP-2 improve nutrient absorption in short bowel syndrome patients?

Common questions

What is GLP-2 and what is it used for?

GLP-2 (glucagon-like peptide 2) is a gut hormone that promotes intestinal growth and slows motility. Its analog, teduglutide, is an FDA-approved treatment for short bowel syndrome — helping patients absorb more nutrients from a shorter intestine.

Why does slowing gut contractions help with nutrient absorption?

When the gut contracts less, food moves through more slowly, giving the intestinal lining more time to absorb nutrients and water. For people with short bowel syndrome, this extra absorption time is critical for maintaining nutrition without IV supplementation.

Read the original research

Contribution of Vasoactive Intestinal Peptide to the Depressant Effects of Glucagon-like Peptide-2 on Neurally Induced Contractile Responses in Mouse Ileal Preparations.

International journal of molecular sciences, 26(24)

View on PubMed ↗Publisher’s paper ↗

Citation

Baccari, Maria Caterina; Conti, Donata; Vannucchi, Maria Giuliana; Idrizaj, Eglantina. (2025). Contribution of Vasoactive Intestinal Peptide to the Depressant Effects of Glucagon-like Peptide-2 on Neurally Induced Contractile Responses in Mouse Ileal Preparations.. International journal of molecular sciences, 26(24). https://doi.org/10.3390/ijms262411797