Intestinal mucosal phospholipid layer

The intestinal mucosal phospholipid layer is a critical structural component of the gut barrier, primarily located on the luminal surface of the colonic mucus. It consists largely of phosphatidylcholine (PC), which provides a hydrophobic surfactant-like property that protects the underlying intestinal epithelium from chemical and bacterial insults (Ehehalt et al., 2004; PMID: 15188465). In inflammatory conditions such as ulcerative colitis, the concentration of phospholipids in the mucus is significantly reduced, compromising the barrier and allowing for the translocation of bacteria that trigger inflammation (Stremmel et al., 2010; PMID: 20517916). Therapeutic interventions aim to replenish this layer using delayed-release or enteric-coated phosphatidylcholine formulations that bypass the small intestine to reach the colon (Stremmel et al., 2005; PMID: 15825125). Conversely, certain drugs like non-steroidal anti-inflammatory drugs (NSAIDs) can disrupt this layer by associating with the phospholipids, contributing to gastrointestinal toxicity (Lichtenberger et al., 1995; PMID: 7744317). This layer also plays a role in lubricating the intestinal surface, facilitating the passage of stool. Restoring the integrity of this phospholipid barrier is a recognized strategy for maintaining clinical remission in patients with ulcerative colitis. Research continues into how the composition of these lipids changes in response to diet and the gut microbiome.

Other names

Colonic mucus phospholipid layerIntestinal surfactant-like layerMucosal hydrophobic barrier

Replenishment of the hydrophobic surfactant-like layer on the intestinal mucosa to restore barrier integrity and prevent pro-inflammatory luminal contents from contacting the epithelium.