:Helenin
{{Chembox
| ImageFile = Alantolactone.svg
| ImageCaption = Alantolactone
| ImageSize = 200px
| ImageFile1 = Isoalantolactone.svg
| ImageCaption1 = Isoalantolactone
| ImageSize1 = 200px
| IUPACName = Alantolactone: (3aR,5S,8aR,9aR)-5,8a-Dimethyl-3-methylene-3a,5,6,7,8,8a,9,9a-octahydronaphtho[2,3-b]furan-2(3H)-one
Isoalantolactone: (3aR,4aS,8aR,9aR)-8a-Methyl-3,5-bis(methylene)decahydronaphtho[2,3-b]furan-2(3H)-one
| OtherNames = Elecampane camphor, Inula camphor, Alant camphor
| Section1 = {{Chembox Identifiers
| index_label = Alantolactone
| index1_label = isolantolactone
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| CASNo1_Ref = {{cascite|correct|CAS}}
| UNII1_Ref = {{fdacite|correct|FDA}}
| CASNo = 546-43-0
| CASNo1 = 470-17-7
| EC_number = 208-899-3
| UNII = M7GSN5Q1M6
| UNII1 = BYH07P620U
| ChemSpiderID = 65564
| ChemSpiderID1 = 66028
| PubChem = 72724
| PubChem1 = 73285
| ChEMBL = 136356
| ChEMBL1 = 137803
| ChEBI = 2540
| ChEBI1 = 5981
| KEGG = C09289
| KEGG1 = C09484
| StdInChI=1S/C15H20O2/c1-9-5-4-6-15(3)8-13-11(7-12(9)15)10(2)14(16)17-13/h7,9,11,13H,2,4-6,8H2,1,3H3/t9-,11+,13+,15+/m0/s1
| StdInChIKey = PXOYOCNNSUAQNS-AGNJHWRGSA-N
| InChI1=1S/C15H20O2/c1-9-5-4-6-15(3)8-13-11(7-12(9)15)10(2)14(16)17-13/h11-13H,1-2,4-8H2,3H3/t11-,12+,13-,15-/m1/s1
| InChIKey1 = CVUANYCQTOGILD-QVHKTLOISA-N
| SMILES = C[C@H]1CCC[C@]2(C1=C[C@H]3[C@@H](C2)OC(=O)C3=C)C
| SMILES1 = C[C@]12CCCC(=C)[C@@H]1C[C@H]3[C@@H](C2)OC(=O)C3=C
}}
| Section2 = {{Chembox Properties
| C = 15 | H = 20 | O = 2
| Appearance = Crystalline powder
| Density =
| MeltingPt =
| BoilingPt =
| Solubility =
}}
| Section3 = {{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
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}}
Helenin is a phytochemical mixture found in many plant species, including the Inula helenium (elecampane) of the family Asteraceae. It is a mixture of two isomeric sesquiterpene lactones, alantolactone and isoalantolactone.
In 1895 the German scientists Julius Bredt and Wilhelm Posh extracted helenin from Inula helenium and determined its physical and chemical properties.{{cite book|last1=Chemical Society (Great Britain)|title=The collected works of Sir Humphry Davy ...: Discourses delivered before the Royal society. Elements of agricultural chemistry, pt. I|date=1895|publisher=Smith, elder and Company|pages=555|url=https://books.google.com/books?id=ksdLAAAAYAAJ&pg=PA555|access-date=31 July 2015}}
Natural sources
Alantolactone occurs in the roots of Inula helenium and other Inula species.{{cite book|last1=Hoffmann|first1=David|title=Medical Herbalism:The Science and Practice of Herbal Medicine|date=2003|publisher=Health & Fitness|isbn=978-1594778902|url=https://books.google.com/books?isbn=1594778906|ref=Google Books}} Helenin discovered in Stevia lucida for the first time, showcasing potential links within the Asteraceae family. {{Cite journal |last1=Chacón-Morales |first1=Pablo A. |last2=Dugarte |first2=Carolina Santiago |last3=Amaro-Luis |first3=Juan M. |date=2021-11-02 |title=Helenin from Stevia lucida . The first report of this natural eudesmanolide mixture in Eupatorieae tribe |url=https://www.tandfonline.com/doi/full/10.1080/14786419.2020.1739677 |journal=Natural Product Research |language=en |volume=35 |issue=21 |pages=4139–4142 |doi=10.1080/14786419.2020.1739677 |pmid=32189507 |issn=1478-6419|url-access=subscription }}
Properties
Helenin can be extracted from the roots of Inula helenium using alcohol or other non-polar solvents to produce a mixture with a composition of about 40% alantolactone and 60% isoalantolactone.{{cite journal|last1=Xu|first1=Renjie|title=Pharmacokinetic Comparison of Isoalantolactone and Alantolactone in Rats after Administration Separately by Optimization of an UPLC-MS2 Method|journal=Journal of Chemistry |date=2014 |volume=2014 |pages=1–8 |doi = 10.1155/2014/354618 |doi-access=free }}
Biological activity
Alantolactone has a variety of in vitro biochemical properties, including:
- induces apoptosis and cell cycle arrest in lung squamous cancer cells{{cite journal|last1=Zhao|first1=Peng|title=Alantolactone Induces Apoptosis and Cell Cycle Arrest on Lung Squamous Cancer SK-MES-1 Cells|journal=Journal of Biochemical and Molecular Toxicology|date=19 Jan 2015|volume=29|issue=5|pages=199–226|doi=10.1002/jbt.21685|pmid=25597476|s2cid=10440798}}
- suppresses STAT3 activation{{cite journal|last1=Chun|first1=J|title=Alantolactone selectively suppresses STAT3 activation and exhibits potent anticancer activity in MDA-MB-231 cells.|journal=Cancer Letters|date=1 Feb 2015|volume=357|issue=1|pages=393–403|doi=10.1016/j.canlet.2014.11.049|url=https://zenodo.org/record/851358
|pmid=25434800}}
- has antiinflammatory effects by inhibiting chemokine production and STAT1 phosphorylation{{cite journal|last1=Hye|first1=Sun Lim|title=Alantolactone from Saussurea lappa Exerts Antiinflammatory Effects by Inhibiting Chemokine Production and STAT1 Phosphorylation in TNF-α and IFN-γ-induced in HaCaT cells|journal=Phytotherapy Research|date=17 Apr 2015|volume=29|issue=7|pages=1088–1096|doi=10.1002/ptr.5354|pmid=25881570|s2cid=5196219|doi-access=free}}
- anti-fungal{{cite journal|last1=Alejandro|first1=Barreroa|title=New sources and antifungal activity of sesquiterpene lactones |journal=Fitoterapia |date=2000 |issue=71 |pages=60–64 |pmid=20095126 |volume=66 |doi=10.1016/s0367-326x(99)00122-7}}
- anti-microbial{{cite journal|last1=O'Shea|first1=S|title=In vitro activity of Inula helenium against clinical Staphylococcus aureus strains including MRSA |journal=British Journal of Biomedical Science |date=2009 |volume=66 |issue=4 |pages=186–9| pmid = 20095126 |doi=10.1080/09674845.2009.11730271}}
Toxicity
Certain individuals have experienced contact dermatitis when exposed to alantolactone.{{cite journal|last1=Stampf|first1=J|title=Allergic contact dermatitis due to sesquiterpene lactones. A comparative study of human and animal sensitivity to alpha-methylene-gamma-butyrolactone and derivatives |journal=The British Journal of Dermatology |date=August 1978 |volume=99 |issue=2 |pages=163–9 | pmid = 698105 |doi=10.1111/j.1365-2133.1978.tb01977.x|s2cid=73218116}}