Cholesterol solubilization in intestinal bile salt micelles

Cholesterol solubilization in intestinal bile salt micelles is a critical physiological process that enables the absorption of hydrophobic cholesterol from the intestinal lumen into enterocytes. Because cholesterol is insoluble in the aqueous environment of the gut, it must be incorporated into mixed micelles composed of bile salts and phospholipids (primarily lecithin) to cross the unstirred water layer and reach the brush border membrane [1][2]. This process is a key therapeutic focal point for lipid-lowering strategies aimed at reducing plasma LDL-cholesterol and preventing cardiovascular disease. For example, plant sterols and stanols lower cholesterol levels by competitively displacing cholesterol from these micelles, thereby reducing its bioavailability for transport by the Niemann-Pick C1-Like 1 (NPC1L1) protein [3]. Furthermore, bile acid sequestrants interfere with this process by binding bile acids, which prevents the formation of the micellar structures necessary for cholesterol solubilization and subsequent absorption [4]. This mechanism is essential for maintaining systemic cholesterol homeostasis and is a primary site of action for non-systemic cholesterol-lowering agents. [1] Wang, D. Q., & Carey, M. C. (1996). J Lipid Res. [2] Abumrad, N. A., & Davidson, N. O. (2012). Physiol Rev. [3] Gylling, H., et al. (2014). Atherosclerosis. [4] Knopp, R. H. (1999). N Engl J Med.

Other names

Micellar cholesterol solubilizationIntestinal mixed micelle formationBile salt-mediated cholesterol transportMicellar solubilization of dietary cholesterol

Competitive displacement of cholesterol from mixed micelles by plant sterols; sequestration of bile acids to prevent micelle formation; inhibition of NPC1L1-mediated uptake of micellar cholesterol.