Description
S-equol is a metabolite of dietary soy isoflavone daidzein by gut microbiome and possesses the most anti-atherogenic properties among all isoflavones.
Chemical Properties
White to Off-White Solid
Uses
A human urinary metabolite of Daidzein. It is also a natural estrogenic metabolite from soy isoflavones
Uses
Receptor; binding activity
Uses
(S)-Equol and R-Equol are metabolites of the soy isoflavones Daidzein (D103500) and Genistein. Both have significant biological actions.
Definition
ChEBI: Equol is a member of hydroxyisoflavans.
benefits
S-equol(EQUOL) is a selective estrogen receptor β (ERβ) agonist with lower binding activity for ERα, the predominant estrogen receptor in the breast and uterus. ERβ is highly expressed in hippocampal neurons . The hippocampus plays a major role in the brain for memory and spatial orientation. Thus, a selective ERβ agonist, such as S-equol, could offer a safe therapeutic or dietary supplement for cognitive improvement.
Biological Activity
(S)-Equol is an isoflavan produced by intestinal bacteria in response to soy isoflavone intake in human. it shows a wide range of activities including antioxidant activity, anti-inflammation activity and anticancer activity. it is reported that equol specifically binds to 5α-dht and has a modest affinity for recombinant estrogen receptor erβ, which may be responsible for most of equol’s biological properties. [1]
Side effects
(S)-Equol(EQUOL) can cause some mild side effects such as constipation and bloating.
Synthesis
Dimethoxybenzodihydropyran (S)-23 (18 g, 66.7 mmol) was dissolved in pyridine hydrochloride (192 g, 148 mL, 1.67 mol), and the reaction mixture was heated at 150 °C overnight and then cooled to room temperature. The reaction solution was neutralized with excess aqueous NaHCO3 and subsequently extracted with dichloromethane (3 x 100 mL). The organic phases were combined and the crude product was purified by column chromatography (eluent: hexane/diethyl ether mixed solvent) to afford (S)-3-(4-hydroxyphenyl)benzodihydropyran-7-ol as a white solid in 88% yield (14.2 g, 58.7 mmol). The product characterization data were as follows: [α]25D = -19.5 (c = 1.05, MeOH), literature value [α]25D = -13 (c = 0.21, ethanol); 1H NMR (400 MHz, CD3OD) δ 7.09 (d, J = 8.5 Hz, 2H), 6.88 (d, J = 8.2 Hz, 1H), 6.76 (d, J = 8.5 Hz, 2H), 6.33 (dd, J = 8.2, 2.5 Hz, 1H), 6.25 (d, J = 2.5 Hz, 1H), 4.20 (tdd, J = 10.5, 3.6, 1.8 Hz, 1H), 3.91 (t, J = 10.5 Hz, 1H), 3.05 (tdd, J = 10.2, 6.0, 3.6 Hz, 1H). 2.93-2.77 (m, 2H); 13C NMR (100 MHz, CD3OD) δ 157.6, 157.3, 156.3, 133.8, 131.2, 129.3 (2C), 116.4 (2C), 114.6, 109.1, 103.8, 72.2, 39.4, 33.0.
Physiological effects
(S)-Equol is a selective estrogen receptor β (ERβ) agonist with lower binding activity for ERα, the predominant estrogen receptor in the breast and uterus. ERβ is highly expressed in hippocampal neurons.
in vitro
in vitro studies were conducted to measure both the binding affinity of equol for 5alpha-dihydrotestosterone (5alpha-dht) and the effects of equol treatment in human prostate cancer (lncap) cells. it was found that equol bound to 5alpha-dht with maximum and half maxim concentrations of 100 nm and 4.8 nm, respectively. in addition, equol significantly offset the increases in psa levels from lncap cells. [1]
in vivo
an in vivo study was performed to investigate effects of equol on rat prostate weight and circulating levels of sex steroid hormones. 1.0 mg/kg of equol was injected to long-evans rats fed with a low isoflavone diet for 25 days. findings from this study suggested that equol significantly decreased rat prostate weights and down-regulated serum levels of 5alpha-dht. however, this agent did not alter levels of lh, testosterone and estradiol. [1]
References
[1]lund td, blake c, bu l, hamaker an, lephart ed. iequol an isoflavonoid: potential for improved prostate health, in vitro and in vivo evidence. reprod biol endocrin. 2011; 9(4): doi: 10.1186/1477-7827-9-4.
[2]setchell dr and clerici c. equol: pharmacokinetics and biological actions. j nutr. 2010 jul; 140(7): 1363s–8s.
