Cholesterol solubilization in bile

"Cholesterol solubilization in bile" is not a molecule or a defined molecular target such as a receptor, enzyme, transporter, or structural protein. Instead, it describes a *physiological process* by which cholesterol, which is poorly soluble in water, is made soluble within bile primarily through the formation of mixed micelles and vesicles that contain bile salts (bile acids), phospholipids (mainly phosphatidylcholine), and cholesterol itself[1][3][4][6]. This process facilitates both the excretion of cholesterol from the liver and its absorption in the intestine, playing a critical role in cholesterol homeostasis, lipid digestion, and the prevention of cholesterol precipitation and gallstone formation[1][2][3][5]. Multiple transporters (such as ABCB11 for bile salts, ABCB4 for phospholipids, and the ABCG5/G8 heterodimer for cholesterol) are critical for this process, but "cholesterol solubilization in bile" is not itself a single protein, gene, or drug target—it refers to the net physicochemical phenomenon arising from the coordinated function of these molecules and the structural dynamics in bile[2][3][4]. Thus, it should not be treated as a canonical drug target or molecular entity.