 | |
| Names | |
|---|---|
| IUPAC name (24S)-Cholest-5-ene-3β,24-diol | |
| Systematic IUPAC name (1R,3aS,3bS,7S,9aR,9bS,11aR)-1-[(2R,5S)-5-Hydroxy-6-methylheptan-2-yl]-9a,11a-dimethyl-2,3,3a,3b,4,6,7,8,9,9a,9b,10,11,11a-tetradecahydro-1H-cyclopenta[a]phenanthren-7-ol | |
| Other names cerebrosterol | |
| Identifiers | |
3D model (JSmol) | |
| 3218472 | |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| KEGG | |
| UNII | |
| |
| |
| Properties | |
| C27H46O2 | |
| Molar mass | 402.663 g·mol−1 |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
24S-Hydroxycholesterol (24S-HC), also known ascholest-5-ene-3,24-diol orcerebrosterol, is anendogenousoxysterol produced byneurons in thebrain to maintaincholesterolhomeostasis.[1] It was discovered in 1953 by Alberto Ercoli, S. Di Frisco, and Pietro de Ruggieri, who first isolated the molecule in the horse brain[2] and then demonstrated its presence in thehuman brain.[3]
24S-HC is produced by ahydroxy groupsubstitution atcarbon number 24 in cholesterol, catalyzed by theenzymecholesterol 24-hydroxylase (CYP46A1).[4]
24S-HC binds toapolipoproteins such asapoE,apoJ, andapoA1 to formHDL-like complexes[5] which can cross theblood–brain barrier more easily than freecholesterol. Thus, 24S-HC production serves as one of several counterbalancing mechanisms for cholesterol synthesis in the brain.[1][6] After entering general blood circulation and traveling to theliver, 24S-HC can besulfated,glucuronidated, or converted intobile acids, which can ultimately beexcreted.[7]
24S-HC is an agonist ofliver X receptors, a class ofnuclear receptors that sense oxysterols. In the brain,liver X receptor beta is the primary LXR type, which interacts with 24S-HC.[5] 24S-HC levels sensed by LXRs can regulate the expression ofSREBP mRNA and protein, which in turn regulatecholesterol synthesis andfatty acid synthesis.[8]
24S-HC may participate in several aspects ofbrain development and function, such asaxon anddendrite growth orsynaptogenesis,[4] as well as acting as a positiveallosteric modulator ofNMDA receptors.[9] Regulation of 24S-HC metabolism in neurons may play a role in their health and function, as well as their response to injury or disease.[10]Blood plasma levels of 24S-HC may be altered after acutebrain injuries such asstroke[11] or inneurodegenerative diseases such asAlzheimer's disease,Huntington's disease, andmultiple sclerosis.[12][13]
