Mucus glycoprotein disulfide bonds and gastrointestinal luminal gas-liquid interfaces

Mucus glycoproteins, primarily mucins such as MUC2, serve as the structural backbone of the gastrointestinal mucus layer, utilizing intermolecular disulfide bonds to form a protective, viscous gel (UniProt, 2024). These glycoproteins interact with luminal gas to create gas-liquid interfaces; when surface tension is high, stable foam or bubbles can form, leading to clinical symptoms such as bloating, flatulence, and abdominal distension (StatPearls: NBK555997, 2023). Therapeutic intervention targeting this system involves two primary mechanisms: the chemical reduction of disulfide bonds by mucolytic agents like N-acetylcysteine to lower mucus viscosity (StatPearls: NBK537183, 2023), and the reduction of surface tension at gas-liquid interfaces by surfactants like simethicone to promote the coalescence of small gas bubbles into larger ones for easier expulsion (PubChem: CID 6433516, 2024). These actions facilitate the clearance of gas and improve the quality of endoscopic visualization by removing obscuring foam from the gastrointestinal tract (PubMed: 31295215, 2019). By modulating both the chemical structure of the mucus and the physical properties of the gas-liquid interface, these treatments manage the mechanical and symptomatic aspects of gastrointestinal health.

Other names

Mucin disulfide bridgesGastrointestinal gas-liquid interfaceGastric foamMucus gel matrixMucus-gas interface

Reduction of disulfide bonds to decrease mucus viscosity and reduction of surface tension to facilitate gas bubble coalescence.