Equilin

Equilin
Clinical data
Other names	Δ7-Estrone; 7-Dehydroestrone; Estra-1,3,5(10),7-tetraen-3-ol-17-one
Routes of; administration	By mouth
Drug class	Estrogen
Identifiers
	IUPAC name (9S,13S,14S)-3-hydroxy-13-methyl-9,11,12,14,15,16-hexahydro-6H-cyclopenta[a]phenanthren-17-one;
CAS Number	474-86-2 ;
PubChem CID	223368;
DrugBank	DB02187 ;
ChemSpider	193995 ;
UNII	08O86EX0J4;
KEGG	D04041 ;
ChEBI	CHEBI:42309 ;
ChEMBL	ChEMBL323533 ;
Chemical and physical data
Formula	C18H20O2
Molar mass	268.356 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES O=C3CC[C@H]4C/2=C/Cc1c(ccc(O)c1)[C@H]\2CC[C@]34C;
	InChI InChI=1S/C18H20O2/c1-18-9-8-14-13-5-3-12(19)10-11(13)2-4-15(14)16(18)6-7-17(18)20/h3-5,10,14,16,19H,2,6-9H2,1H3/t14-,16+,18+/m1/s1 ; Key:WKRLQDKEXYKHJB-HFTRVMKXSA-N ;
	(verify)

Short description: Chemical compound

Equilin is a naturally occurring estrogen sex hormone found in horses as well as a medication.^[1]^[2]^[3] It is one of the estrogens present in the estrogen combination drug preparations known as conjugated estrogens (CEEs; e.g. Premarin) and esterified estrogens (EEs; e.g. Estratab, Menest).^[2]^[3] CEEs is the most commonly used form of estrogen medications in hormone replacement therapy (HRT) for menopausal symptoms in the United States .^[3] Estrone sulfate is the major estrogen in CEEs (about 50%) while equilin sulfate is the second major estrogen in the formulation, present as about 25% of the total.^[2]^[3]

Pharmacology

Pharmacodynamics

Equilin is an estrogen, or an agonist of the estrogen receptors (ERs), the ERα and ERβ.^[2] In terms of relative binding affinity for the ERs, equilin has about 13% and 49% of that of estradiol for the ERα and ERβ, respectively.^[2] Analogously to the reversible transformation of estrone into estradiol by 17β-hydroxysteroid dehydrogenase, equilin can be converted into the more potent estrogen 17β-dihydroequilin in the body.^[2]^[3] This estrogen has about 113% and 108% of the relative binding affinities of estradiol for the ERα and ERβ, respectively.^[2]^[3] Equilin is present in CEEs in the form of equilin sulfate, which itself is inactive and acts as a prodrug of equilin via steroid sulfatase.^[2]^[3]

Similarly to synthetic estrogens like ethinylestradiol, equilin and CEEs have disproportionate effects in certain tissues such as the liver and uterus relative to bioidentical human estrogens like estradiol and estrone.^[2] Because of their disproportionate potency in the liver, equilin and CEEs have relatively increased effects on liver protein synthesis compared to estradiol.^[2]

A dosage of 0.25 mg/day equilin sulfate is equivalent to 0.625 mg/day CEEs in terms of relief from hot flashes.^[2] At a dosage of 0.625 mg/day equilin sulfate, the increases in circulating levels of sex hormone-binding globulin (SHBG), corticosteroid-binding globulin, and angiotensinogen were 1.5 to 8 times those observed with estrone sulfate.^[2] Equilin has about 42% of the relative potency of CEEs in the vagina and 80% of the relative potency of CEEs in the uterus, while its more active form, 17β-dihydroequilin, has about 83% of the relative potency of CEEs in the vagina and 200% of the relative potency of CEEs in the uterus.^[2]

Pharmacokinetics

Equilin has about 8% of the relative binding affinity of testosterone for SHBG, relative to 12% in the case of estrone.^[2] In terms of plasma protein binding, it is bound 26% to SHBG and 13% to albumin.^[2] The metabolic clearance rates of equilin and equilin sulfate are 2,640 L/day/m² and 175 L/day/m², respectively.^[2] In accordance, the biological half-life of equilin sulfate is substantially longer than that of equilin.^[2] Equilin is converted into 17β-dihydroequilin in the liver and in other tissues.^[2]^[3] Equilin and 17β-dihydroequilin can also be transformed into equilenin and 17β-dihydroequilenin.^[2]^[3] Equilin is excreted in the form of glucuronide conjugates.^[2]

Chemistry

Equilin, also known as δ⁷-estrone or as 7-dehydroestrone, as well as estra-1,3,5(10),7-tetraen-3-ol-17-one, is a naturally occurring estrane steroid and an analogue of estrone.^[2]^[3] In terms of chemical structure and pharmacology, equilin is to 17β-dihydroequilin (δ⁷-17β-estradiol) as estrone is to estradiol.^[2]^[3]

References

↑ J. Elks (14 November 2014). The Dictionary of Drugs: Chemical Data: Chemical Data, Structures and Bibliographies. Springer. p. 495. ISBN 978-1-4757-2085-3. https://books.google.com/books?id=0vXTBwAAQBAJ&pg=PA298.
↑ ^2.00 ^2.01 ^2.02 ^2.03 ^2.04 ^2.05 ^2.06 ^2.07 ^2.08 ^2.09 ^2.10 ^2.11 ^2.12 ^2.13 ^2.14 ^2.15 ^2.16 ^2.17 ^2.18 ^2.19 ^2.20 ^2.21 "Pharmacology of estrogens and progestogens: influence of different routes of administration". Climacteric 8 (Suppl 1): 3–63. 2005. doi:10.1080/13697130500148875. PMID 16112947. http://hormonebalance.org/images/documents/Kuhl%2005%20%20Pharm%20Estro%20Progest%20Climacteric_1313155660.pdf.
↑ ^3.00 ^3.01 ^3.02 ^3.03 ^3.04 ^3.05 ^3.06 ^3.07 ^3.08 ^3.09 ^3.10 "Pharmacology of conjugated equine estrogens: efficacy, safety and mechanism of action". J. Steroid Biochem. Mol. Biol. 142: 16–29. July 2014. doi:10.1016/j.jsbmb.2013.10.011. PMID 24176763.

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/Equilin. Read more

[Elks2014-1] J. Elks (14 November 2014). The Dictionary of Drugs: Chemical Data: Chemical Data, Structures and Bibliographies. Springer. p. 495. ISBN 978-1-4757-2085-3. https://books.google.com/books?id=0vXTBwAAQBAJ&pg=PA298.

[pmid16112947-2] 2.00 ^2.01 ^2.02 ^2.03 ^2.04 ^2.05 ^2.06 ^2.07 ^2.08 ^2.09 ^2.10 ^2.11 ^2.12 ^2.13 ^2.14 ^2.15 ^2.16 ^2.17 ^2.18 ^2.19 ^2.20 ^2.21 "Pharmacology of estrogens and progestogens: influence of different routes of administration". Climacteric 8 (Suppl 1): 3–63. 2005. doi:10.1080/13697130500148875. PMID 16112947. http://hormonebalance.org/images/documents/Kuhl%2005%20%20Pharm%20Estro%20Progest%20Climacteric_1313155660.pdf.

[pmid24176763-3] 3.00 ^3.01 ^3.02 ^3.03 ^3.04 ^3.05 ^3.06 ^3.07 ^3.08 ^3.09 ^3.10 "Pharmacology of conjugated equine estrogens: efficacy, safety and mechanism of action". J. Steroid Biochem. Mol. Biol. 142: 16–29. July 2014. doi:10.1016/j.jsbmb.2013.10.011. PMID 24176763.

[1]

[2]

[3]