Targeting AMPK for the Control of Intestinal epithelial barrier integrity – TACI

Our project combines molecular and functional analyses of healthy and diseased human samples with studies in mouse models that develop chronic inflammation of varying severity, with or without AMPK activation in intestinal epithelial cells.

The expected results rely on the use of complementary experimental models and analytical approaches that make it possible to study the intestinal barrier at multiple levels, from individual cells to the whole organism. On one hand, the use of cell cultures and pharmacological treatments targeting AMPK provides essential tools for testing new therapeutic strategies. On the other hand, generation of genetically modified mice lacking AMPK specifically in the intestinal epithelium allow precise identification of the role of this enzyme in intestinal permeability, inflammation, and metabolic disorders. Experimental models of intestinal inflammation that reproduce key features of human disease, combined with functional measurements of permeability and analysis of proteins that maintain cell cohesion, enable direct evaluation of the intestine’s ability to repair itself. In addition, the study of human intestinal samples and their lipid profiles, helps connect experimental findings with real clinical situations.

By combining these advanced technologies, the project addresses a major scientific challenge: understanding how to effectively restore intestinal barrier integrity after inflammation. This integrated approach is expected to identify concrete therapeutic targets and pave the way for new treatments aimed at long-term protection of intestinal health.

Our work seeks to better understand the role of an enzyme called AMPK in protecting and repairing the intestinal barrier, which is essential for preventing bacteria and harmful substances from entering the body. To do this, we used a mouse model of colitis that reproduces key features of inflammatory bowel disease. Mice lacking AMPK specifically in intestinal epithelial cells were compared with normal mice. At the early stage of inflammation, both groups showed similar signs of disease. However, colon inflammation remained more pronounced in mice without AMPK. Most importantly, during the repair phase, these mice displayed a weaker intestinal barrier, reduced expression of proteins responsible for cell cohesion, more extensive tissue damage, and more severe inflammation. The absence of AMPK also delayed mucosal regeneration and the restoration of Goblet cells, which are essential for intestinal healing. These findings demonstrate that AMPK plays a crucial role in intestinal regeneration following inflammation. In humans, inflammatory lesions induced on human epithelium (organoid model) are not blocked by pharmacological activation of AMPK. However, further analysis shows that it is not only AMPK activity that is reduced by inflammation, but also its expression. This is consistent with analyses of the mucosa of patients with chronic inflammatory bowel disease, which reveal that AMPK expression is reduced in patients with ulcerative colitis (UC), but not in patients with Crohn's disease.

Our results show that AMPK is a key driver of intestinal barrier regeneration after inflammation. This discovery opens several promising perspectives for human health.

First, it suggests that drugs capable of activating AMPK could promote intestinal repair and reduce complications associated with Crohn’s disease, potentially improving patients’ quality of life by decreasing flare severity and accelerating mucosal healing. Considering patients with UC, it is AMPK expression that needs to be restored before even considering activating it.

Second, our work provides deeper insight into the cellular and molecular mechanisms that maintain intestinal barrier integrity, offering a foundation for the development of targeted therapies designed to strengthen cell cohesion and restore Goblet cell function, both essential for healing.

In the long term, this research paves the way for personalised therapeutic approaches and preventive strategies aimed at preserving intestinal barrier function and promoting lifelong intestinal health through modulation of AMPK and restoration of intestinal homeostasis.

Rupture of intestinal epithelial barrier (IEB) integrity is associated with a variety of gastrointestinal disorders. In particular IEB permeability is increased in inflammatory bowel disease or obesity and strengthening of the IEB has been associated with better clinical outcomes. Our preliminary data has identified AMP-activated protein kinase (AMPK) as an epithelial target of permeability regulation, but data regarding its role in IEB integrity remain sparse. The overall objective of this project is to study the role of AMPK in the maintenance of IEB homeostasis. The specific aims are 1) to explore the impact of AMPK dysregulation on IEB rupture and development inflammation; 2) to validate strategies of IEB strengthening or restoration by activation of AMPK. Our project will combine molecular and functional analyzes of human pathological/control samples to examination of mice model developing low or high grade chronic inflammation with or without AMPK activation in epithelial cells.