Dietary lipid micelle

Dietary lipid micelles are temporary supramolecular assemblies formed within the intestinal lumen during the digestion of dietary fats (Hussain, 2014). They are primarily composed of bile salts, phospholipids, long-chain fatty acids, and 2-monoacylglycerols, which spontaneously aggregate once they reach a critical micellar concentration (StatPearls, 2023). Their fundamental biological role is to solubilize hydrophobic lipids and fat-soluble vitamins (A, D, E, and K), allowing these substances to traverse the aqueous environment of the intestinal unstirred water layer to reach the enterocyte surface for absorption (Borgström, 1975). While not a traditional protein target, dietary lipid micelles are central to the pharmacology of lipid-lowering agents. For instance, ezetimibe inhibits the transport of cholesterol from these micelles into enterocytes via the NPC1L1 transporter, and bile acid sequestrants prevent micelle formation by binding the bile salts necessary for their assembly (Phan et al., 2015). Understanding micellar dynamics is essential for treating lipid metabolism disorders and ensuring the bioavailability of lipophilic drugs (Mu & Høy, 2004).

Other names

Mixed micelleIntestinal micelleBile salt micelleLipid-bile salt aggregate

Inhibition of micelle formation through bile acid sequestration or inhibition of lipid transport from the micelle into enterocytes.