:Lanosterol

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| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 393354387

| ImageFile = Lanosterol skeletal.svg

| ImageSize = 250

| ImageFile2 = Lanosterol molecule ball.png

| ImageSize2 = 250

| ImageAlt2 = Ball-and-stick model of lanosterol

| IUPACName = Lanosta-8,24-dien-3β-ol

| SystematicName = (1R,3aR,5aR,7S,9aS,11aR)-3a,6,6,9a,11a-Pentamethyl-1-[(2R)-6-methylhept-5-en-2-yl]-2,3,3a,4,5,5a,6,7,8,9,9a,10,11,11a-tetradecahydro-1H-cyclopenta[a]phenanthren-7-ol

| OtherNames =

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 79-63-0

| Beilstein = 2226449

| ChEBI_Ref = {{ebicite|correct|EBI}}

| ChEBI = 16521

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 225111

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 216175

| DrugBank = DB03696

| EC_number = 201-214-9

| IUPHAR_ligand = 2746

| KEGG = C01724

| MeSHName = Lanosterol

| PubChem = 246983

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = 1J05Z83K3M

| InChI = 1/C30H50O/c1-20(2)10-9-11-21(3)22-14-18-30(8)24-12-13-25-27(4,5)26(31)16-17-28(25,6)23(24)15-19-29(22,30)7/h10,21-22,25-26,31H,9,11-19H2,1-8H3/t21-,22-,25+,26+,28-,29-,30+/m1/s1

| InChIKey = CAHGCLMLTWQZNJ-BQNIITSRBP

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C30H50O/c1-20(2)10-9-11-21(3)22-14-18-30(8)24-12-13-25-27(4,5)26(31)16-17-28(25,6)23(24)15-19-29(22,30)7/h10,21-22,25-26,31H,9,11-19H2,1-8H3/t21-,22-,25+,26+,28-,29-,30+/m1/s1

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = CAHGCLMLTWQZNJ-BQNIITSRSA-N

| SMILES = C[C@H](CCC=C(C)C)[C@H]1CC[C@]2(C)C1CCC3=C2CC[C@H]4C(C)(C)[C@@H](O)CC[C@]34C

}}

|Section2={{Chembox Properties

| Formula = C₃₀H₅₀O

| MolarMass = 426.71 g/mol

| Appearance =

| Density =

| MeltingPtC = 138 to 140

| MeltingPt_notes =

| BoilingPt =

}}

|Section3={{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

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Lanosterol is a tetracyclic triterpenoid and is the compound from which all animal and fungal steroids are derived. By contrast, plant steroids are produced via cycloartenol.{{cite journal|last1=Schaller|first1=Hubert|title=The role of sterols in plant growth and development|journal=Progress in Lipid Research|date=May 2003|volume=42|issue=3|pages=163–175|doi=10.1016/S0163-7827(02)00047-4|pmid=12689617}} In the eyes of vertebrates, lanosterol is a natural constituent, having a role in maintaining health of the lens. Lanosterol is the precursor to cholesterol.

Biosynthesis

The biosynthesis of lanosterol has been intensively investigated.{{cite journal |doi=10.1021/cr200021m |title=Biosynthesis of cholesterol and other sterols |date=2011 |last1=Nes |first1=W. David |journal=Chemical Reviews |volume=111 |issue=10 |pages=6423–6451 |pmc=3191736 }}

class="wikitable" ! Description !! Illustration !! Enzyme
Two molecules of farnesyl pyrophosphate condense with reduction by NADPH to form squalene	400px	squalene synthase
Squalene is oxidized to 2,3-oxidosqualene (squalene epoxide)	400x400px	squalene monooxygenase
2,3-Oxidosqualene is converted to a protosterol cation and finally to lanosterol	400px	lanosterol synthase
(step 2)	400px	(step 2)

Elaboration of lanosterol under enzyme catalysis leads to other steroids. 14-Demethylation of lanosterol by CYP51 eventually yields cholesterol.

Image:Sterol synthesis.svg (IPP), dimethylallyl pyrophosphate (DMAPP), geranyl pyrophosphate (GPP), and squalene shown. Some intermediates are omitted.]]

Research as an eye drop supplement

As a molecule naturally enriched in the eye lens, lanosterol is a component involved in maintenance of lens clarity.{{cite journal |vauthors=Daszynski DM, Santhoshkumar P, Phadte AS, Sharma KK, Zhong HA, Lou MF, Kador PF|display-authors=3 |title=Failure of oxysterols such as lanosterol to restore lens clarity from cataracts |journal=Scientific Reports |volume=9 |issue=1 |pages=8459 |date=June 2019 |pmid=31186457 |pmc=6560215 |doi=10.1038/s41598-019-44676-4}}{{cite journal |vauthors=Xu J, Fu Q, Chen X, Yao K |title=Advances in pharmacotherapy of cataracts |journal=Annals of Translational Medicine |volume=8 |issue=22 |pages=1552 |date=November 2020 |pmid=33313297 |pmc=7729355 |doi=10.21037/atm-20-1960|doi-access=free}} Its proposed mechanism of action is to inhibit the aggregation of crystallin proteins, which contribute to the clouding of vision by forming cataracts.

Lanosterol is under research for its potential as a therapeutic additive in eye drops to inhibit the aggregation of crystallin proteins and dissolve cataracts. However, supplemental lanosterol in eye drops appears to have limited solubility and poor bioavailability in the eye, and has not proved effective for inhibiting cataracts, as of 2020.

References

Category:Sterols

Category:Triterpenes

Category:Lanostanes

:Lanosterol

Biosynthesis

Research as an eye drop supplement

See also

References