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| 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 | |
PubChem CID |
|
| UNII | |
CompTox Dashboard (EPA) |
|
| |
| |
| Properties | |
| C27H46O2 | |
| Molar mass | 402.663 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
24S-Hydroxycholesterol (24S-HC), also known as cholest-5-ene-3,24-diolorcerebrosterol, is an endogenous oxysterol produced by neurons in the brain to maintain cholesterol homeostasis.[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 the human brain.[3]
24S-HC is produced by a hydroxy group substitutionatcarbon number 24 in cholesterol, catalyzed by the enzyme cholesterol 24-hydroxylase (CYP46A1).[4]
24S-HC binds to apolipoproteins such as apoE, apoJ, and apoA1 to form HDL-like complexes[5] which can cross the blood–brain barrier more easily than free cholesterol. 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 the liver, 24S-HC can be sulfated, glucuronidated, or converted into bile acids, which can ultimately be excreted.[7]
24S-HC is an agonist of liver X receptors, a class of nuclear 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 of SREBP mRNA and protein, which in turn regulate cholesterol synthesis and fatty acid synthesis.[8]
24S-HC may participate in several aspects of brain development and function, such as axon and dendrite growth or synaptogenesis,[4] as well as acting as a positive allosteric modulatorofNMDA 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 acute brain injuries such as stroke[11] or in neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, and multiple sclerosis.[12][13]
