Endogenous Metabolite; steroid hormone

Estradiol (10 nM, 7 d) stimulates neuronal development and enhances axonal branching in human endometrial stem cells (hEnSCs) [1]. Estradiol (17β-estradiol, 10 nM, 7 days) boosts the expression of neuron-like cell markers (Tuj-1, nestin and NF-H) in neuronal-like cells generated from hEnSCs [1].

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Human endometrial stem cells (hEnSCs) that can be differentiated into various neural cell types have been regarded as a suitable cell population for neural tissue engineering and regenerative medicine. Considering different interactions between hormones, growth factors, and other factors in the neural system, several differentiation protocols have been proposed to direct hEnSCs towards specific neural cells. The 17β-estradiol (E2) plays important roles in the processes of development, maturation, and function of nervous system. In the present research, the impact of 17β-estradiol (estrogen, E2) on the neural differentiation of hEnSCs was examined for the first time, based on the expression levels of neural genes and proteins. In this regard, hEnSCs were differentiated into neuron-like cells after exposure to retinoic acid (RA), epidermal growth factor (EGF), and also fibroblast growth factor-2 (FGF2) in the absence or presence of 17β-estradiol. The majority of cells showed a multipolar morphology. In all groups, the expression levels of nestin, Tuj-1 and NF-H (neurofilament heavy polypeptide) (as neural-specific markers) increased during 14 days. According to the outcomes of immunofluorescence (IF) and real-time PCR analyses, the neuron-specific markers were more expressed in the estrogen-treated groups, in comparison with the estrogen-free ones. These findings suggest that 17β-estradiol along with other growth factors can stimulate and upregulate the expression of neural markers during the neuronal differentiation of hEnSCs. Moreover, our findings confirm that hEnSCs can be an appropriate cell source for cell therapy of neurodegenerative diseases and neural tissue engineering [1].

Estradiol (1 nM, hippocampus slices from FBN-ARO-KO mice) restores LTP amplitude [1]. Estradiol (0.0167 mg, subcutaneously implanted) corrects molecular and functional abnormalities in FBN-ARO-KO mice [1].

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Depletion of neuron-derived 17β-estradiol (E2) leads to a significant decrease in dendritic spine density. Loss of neuron-derived E2 leads to a significant decrease in synapse number. Functional synaptic plasticity is significantly impaired in FBN-ARO-KO mice and rescued by acute E2 treatment. In vivo exogenous E2 replacement rescues the molecular and functional deficits in FBN-ARO-KO mice. [2]

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17β-estradiol (E2) is produced from androgens via the action of the enzyme aromatase. E2 is known to be made in neurons in the brain, but its precise functions in the brain are unclear. Here, we used a forebrain-neuron-specific aromatase knock-out (FBN-ARO-KO) mouse model to deplete neuron-derived E2 in the forebrain of mice and thereby elucidate its functions. FBN-ARO-KO mice showed a 70–80% decrease in aromatase and forebrain E2 levels compared with FLOX controls. Male and female FBN-ARO-KO mice exhibited significant deficits in forebrain spine and synaptic density, as well as hippocampal-dependent spatial reference memory, recognition memory, and contextual fear memory, but had normal locomotor function and anxiety levels. Reinstating forebrain E2 levels via exogenous in vivo E2 administration was able to rescue both the molecular and behavioral defects in FBN-ARO-KO mice. Furthermore, in vitro studies using FBN-ARO-KO hippocampal slices revealed that, whereas induction of long-term potentiation (LTP) was normal, the amplitude was significantly decreased. Intriguingly, the LTP defect could be fully rescued by acute E2 treatment in vitro. Mechanistic studies revealed that FBN-ARO-KO mice had compromised rapid kinase (AKT, ERK) and CREB-BDNF signaling in the hippocampus and cerebral cortex. In addition, acute E2 rescue of LTP in hippocampal FBN-ARO-KO slices could be blocked by administration of a MEK/ERK inhibitor, further suggesting a key role for rapid ERK signaling in neuronal E2 effects. In conclusion, the findings provide evidence of a critical role for neuron-derived E2 in regulating synaptic plasticity and cognitive function in the male and female brain.

For the in vitro 17β-estradiol (E2) rescue experiment, E2 was dissolved in DMSO, diluted to working concentration (1 nm) in oxygenated ACSF (Di Mauro et al., 2015). A DMSO (0.001%) vehicle control was also included in the experiment. In addition, the MEK inhibitor, U0126 (Cell Signaling Technology, catalog #9903S, 10 μm) was also dissolved in DMSO and diluted to working concentration in oxygenated ACSF. U0126 was coadministered with E2. The drugs were applied for all the recording period 20 min before the application of the stimulation protocol.[2]

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Measurement of 17β-estradiol (E2) levels. [2]
17β-estradiol (E2) levels in hippocampal CA1, cortex, and serum were measured using a high-sensitivity ELISA kit, as we described previously (Zhang et al., 2014). Briefly, 100 μl of sample was added into the bottom of an appropriate well coated with a donkey anti-sheep polyclonal antibody. Subsequently, 50 μl of E2 conjugate was added, followed by 50 μl of sheep polyclonal antibody, to E2. The plate was then sealed and incubated at room temperature with shaking speed of ∼500 rpm for 2 h. After washing 3 times with 400 μl of wash buffer each time, 200 μl of pNpp substrate was added into each well and incubated for 1 h at room temperature without shaking. Afterward, 50 μl of stop solution was added into each well and the optical density was read at 405 nm.

Cell Differentiation Assay[1]
Cell Types: Isolated human endometrial stem cells (hEnSCs) from human endometrial tissue
Tested Concentrations: 10 nM
Incubation Duration: 7 days
Experimental Results: Increased the number of neurite processes including neural differentiation and neurite branching.

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Immunofluorescence[1]
Cell Types: Isolated human endometrial stem cells (hEnSCs) from human endometrial tissue
Tested Concentrations: 10 nM
Incubation Duration: 7 days
Experimental Results: Increased the percentage of neural marker (Tuj-1, nestin and NF-H)-positive cells of 62.2±1.3%, 71.5±4% and 51.2±1.5% respectively.

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Neuronal differentiation of hEnSCs [1]
To induce neuronal differentiation, about 3 × 104 hEnSCs were seeded on each well of 24-well culture plates and incubated with two different differentiation media during 14 days. Cells were initially incubated with DMEM/F12 complete medium containing 1% Pen-Strep and also 10% FBS for 24 h at 37°C. In the first group, to induce neuronal differentiation of hEnSCs, we replaced the culture medium with the first step induction medium (DMEM/F12 containing EGF and FGF2 [each at 20 ng/ml concentration] and B27 [1%]) for 7 days. To continue neuronal differentiation, cells were subsequently exposed to the second step induction medium (DMEM/F12 supplemented with 1% ITS, 0.5 µM RA, and 20 ng/ml FGF2) for the next 7 days. In the second group, after 24 h of initial incubation, the expansion medium was replaced with the first step induction medium (DMEM/F12 containing EGF and FGF2 [each at 20 ng/ml concentration] and B27 [1%]) for 7 days and after that, cells were treated with the second step induction medium (DMEM/F12 supplemented with 1% ITS, 0.5 µM RA, 20 ng/ml FGF2, and 10 nM 17β-estradiol (E2) [Kang et al., 2007]) until day 14. Cells in the control groups were cultured on TCP in the presence of DMEM/F12 supplemented with 1% Pen-Strep and 10% FBS for 14 days. All media were changed every 2 days (Figure 1).

Animal/Disease Models: FBN-ARO-KO Mice[2]
Doses: 1 nM
Route of Administration: Treated for the hippocampal slices
Experimental Results: Rescued long-term potentiation (LTP) amplitude of both male and female mice.

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Animal/Disease Models: FBN-ARO-KO Mice [2]
Doses: 0.0167 mg
Route of Administration: Alzet minipumps with Estradiol (implanted sc), examined 7 days after minipump implantation.
Experimental Results: Restored hippocampal and cortical E2 levels to 93%, phosphorylation of AKT, ERK and CREB in the hippocampus and cortex to 90-95%, BDNF level to 80-90%, restored both synaptophysin and PSD95 in the forebrain. Rescued the spatial learning and memory defects.

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n vivo 17β-estradiol (E2) rescue experiment. [2]
Three-month-old ovx female mice were used in this experiment, which were divided into four groups: FLOX + placebo, FLOX + E2, FBN-ARO-KO + placebo, and FBN-ARO-KO + E2. Alzet minipumps osmotic minipumps; model 1007D, 7 d release; Durect) with placebo or E2 (0.0167 mg) were implanted subcutaneously in the upper midback region at the time of ovariectomy. The dose of E2 used here yields stable serum levels of 26.52 ± 0.89 pg/ml, which represents a physiological diestrus II–proestrus level of E2 (Nelson et al., 1981). Molecular and functional endpoints were examined 7 d after minipump implantation.

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Experimental design and statistical analyses. [2]
All quantitative analyses were performed on age-matched FLOX control and FBN-ARO-KO mice. Except for the in vivo 17β-estradiol (E2) rescue experiment, both male and female mice were used. Only female mice were used for in vivo E2 replacement. For behavioral tests, 8–10 mice were used for each group; otherwise, 4–6 samples from each group were analyzed. SigmaStat 3.5 software was used to analyze all data. Data represented in bar graphs were expressed as mean ± SE. A Student's t test was performed when only comparing two groups. Statistical data from the Barnes maze training trial, fear acquisition test, electrophysiological measurements, and part of the in vivo E2 replacement experiments requiring multiple groups comparisons were analyzed with two-way ANOVA followed by Tukey's all pairwise comparisons test to determine group differences. A value of p < 0.05 was considered statistically significant.

Absorption, Distribution and Excretion
The following describes the absorption of several estradiol formulations: Oral Tablets and Injections: Estradiol tablets undergo rapid first-pass metabolism in the gastrointestinal tract before entering systemic circulation. Due to the significant first-pass effect, the bioavailability of oral estrogens is reportedly only 2-10%. Esterification of estradiol can increase its lipophilicity, thereby improving the effect of administration (e.g., estradiol valerate) or prolonging the release of intramuscularly injected sustained-release formulations (including estradiol cyclopentylpropionate). After absorption, the ester group is cleaved, releasing endogenous estradiol or 17β-estradiol. Transdermal Formulations: Transdermal formulations slowly release estradiol through intact skin, thus maintaining circulating estradiol levels for up to one week. Notably, the bioavailability of estradiol after transdermal administration is approximately 20 times higher than that after oral administration. Transdermal administration avoids first-pass metabolism, thereby improving bioavailability. Peak plasma concentration (Cmax) after gluteal administration is approximately 174 pg/mL, while peak plasma concentration after abdominal administration is approximately 147 pg/mL. Spray: After daily use, estradiol spray reaches steady-state plasma concentrations within 7–8 days. After three daily sprays, the peak plasma concentration is approximately 54 pg/mL, with a time to peak concentration (Tmax) of 20 hours. The area under the curve (AUC) is approximately 471 pg·hr/mL. Vaginal ring and cream: Estradiol is effectively absorbed through the vaginal mucosa. Vaginal administration avoids first-pass metabolism. The time to peak concentration after vaginal ring administration is 0.5 to 1 hour. The peak plasma concentration is approximately 63 pg/mL. The peak plasma concentration (Cmax) of estradiol (one of the components of premeridine vaginal estrogen conjugate cream) in this vaginal cream formulation was 12.8 ± 16.6 pg/mL, the time to peak concentration (Tmax) was 8.5 ± 6.2 hours, and the area under the curve (AUC) was 231 ± 285 pg•hr/mL. Estradiol is excreted in the urine as a glucuronide and sulfate conjugate. The distribution of exogenous estrogens is similar to that of endogenous estrogens. They are distributed throughout the body, especially in sex hormone target organs such as the breast, ovaries, and uterus. In one pharmacokinetic study, the clearance of orally administered micronized estradiol in postmenopausal women was 29.9 ± 15.5 mL/min/kg. Another study showed that the clearance of intravenously administered estradiol was 1.3 mL/min/kg. Therapeutic estrogens can be effectively absorbed through the skin, mucous membranes, and gastrointestinal tract. Vaginal administration avoids first-pass metabolism.
The estradiol transdermal continuous delivery system (once weekly) continuously releases estradiol, which is absorbed through intact skin, thus maintaining circulating estradiol levels over a 7-day treatment period. Systemic bioavailability of estradiol after transdermal administration is approximately 20 times that after oral administration. This difference is due to the avoidance of first-pass metabolism when estradiol is administered transdermally.
In a phase I study of 14 postmenopausal women, insertion of the ESTRING (estradiol vaginal ring) rapidly increased serum estradiol (E2) levels. The time to peak serum estradiol (Tmax) ranged from 0.5 to 1 hour. After the initial peak, serum estradiol concentrations rapidly declined over the next 24 hours, showing little difference from baseline mean (range: 5 to 22 pg/mL). Serum estradiol and estrone (E1) levels remained relatively stable over 12 weeks of ring placement in the vaginal fornix.
Table: Estimated Pharmacokinetic Mean Values After a Single Administration of Estrogen Cycle [Table #4649]

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Metabolism/Metabolites
Exogenous estrogens are metabolized in the same way as endogenous estrogens. Metabolic conversions mainly occur in the liver and intestines. Estradiol is metabolized to estrone, both of which can be converted to estriol, which is eventually excreted in the urine. Sulfate- and glucuronide-bound estrogens are also metabolized in the liver. Metabolic conjugates are secreted into the intestine via bile, where they are hydrolyzed and subsequently reabsorbed. Hepatic cytochrome P450 enzyme CYP3A4 plays an important role in the metabolism of estradiol. CYP1A2 is also involved.
Exogenous estrogens are metabolized in the same way as endogenous estrogens. Circulating estrogens are in a dynamic equilibrium of metabolic interconversions. These conversions mainly occur in the liver. Estradiol is reversibly converted to estrone, both of which can be converted to estriol, which is the main urinary metabolite. Estrogens also circulate enterohepaticly via sulfate and glucuronide conjugation in the liver. These conjugates are secreted into the intestine via bile and hydrolyzed there before being reabsorbed. In postmenopausal women, a significant portion of circulating estrogen exists as sulfate conjugates, particularly estrone sulfate, which serves as a circulating reserve for the synthesis of more potent estrogens. Estradiol metabolism varies depending on the stage of the menstrual cycle. Typically, the hormone undergoes rapid biotransformation in the liver, with a plasma half-life measured in minutes. Estradiol is primarily converted to estriol, the main urinary metabolite. Various sulfate and glucuronide conjugates are also excreted in the urine. Estradiol-17β and estrone are metabolized similarly in rats and humans, with both species primarily converting these steroids via (aromatic) 2-hydroxylation and 16α-hydroxylation. Glucuronides of various metabolites are excreted via bile. The main difference between human and rat estrogen metabolism lies in the type of conjugate. In rats, a relatively large proportion of estrone, estradiol-17β, and estriol are converted into metabolites oxidized at both C-2 and C-16 positions. When rats are administered estriol, the glucuronide of 16-ketoestradiol, along with small amounts of sulfate, and the 2- and 3-methyl ethers of 2-hydroxyestriol and 2-hydroxy-16-ketoestradiol, are excreted in bile. In contrast, hydroxylation of estradiol-17β and estrone at C-6 or C-7 of the B ring is a minor pathway in rats. 2-Hydroxyestrogens (“catechol estrogens”) can be further converted via multiple pathways, including covalent binding to proteins. For more complete metabolite/metabolite data on estradiol (a total of 8 metabolites), please visit the HSDB record page.
Known human metabolites of 17β-estradiol include 2-hydroxyestradiol, 4-hydroxyestradiol, 17β-estradiol-3-glucuronide, and 17β-estradiol glucuronide.
The metabolic mechanism of exogenous estrogens is the same as that of endogenous estrogens. Estrogens are partially metabolized by cytochrome P450.
Elimination pathway: Estradiol, estrone, and estriol are excreted in the urine as glucuronide and sulfate conjugates.
Half-life: 36 hours
Biological half-life

It has been reported that the terminal half-life of various estrogen products, administered orally or intravenously, is 1–12 hours. A pharmacokinetic study of oral estradiol valerate in postmenopausal women showed a terminal elimination half-life of 16.9 ± 6.0 hours. Another pharmacokinetic study of intravenously administered estradiol in postmenopausal women showed an elimination half-life of 27.45 ± 5.65 minutes. The half-life of estradiol appears to vary depending on the route of administration. ...After oral administration...the terminal half-life is 20.1 hours...

Toxicity Summary
Estradiol can freely enter target cells (e.g., female organs, breasts, hypothalamus, pituitary gland) and interact with target cell receptors. Once the estrogen receptor binds to its ligand, it enters the target cell nucleus, regulating gene transcription to form messenger RNA (mRNA). The mRNA interacts with ribosomes to produce specific proteins that express the effects of estradiol on target cells. Estrogen can increase the synthesis of sex hormone-binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins in the liver, and inhibit the secretion of follicle-stimulating hormone (FSH) from the anterior pituitary gland. Interactions Estrogen may interfere with the action of bromocriptine; dosage adjustments may be necessary. Estrogen The combined use of testosterone and estradiol-B17 after methylnitrosourea treatment can also lead to prostate adenocarcinoma. Concomitant use with estrogen may increase calcium absorption and exacerbate kidney stones in susceptible individuals; this can be used as a therapeutic advantage to increase bone mass. Estrogens
The co-administration of estrogens with glucocorticoids may alter the metabolism and protein binding of glucocorticoids, leading to decreased clearance, prolonged elimination half-life, and enhanced therapeutic and toxic effects of glucocorticoids; dose adjustments of glucocorticoids may be necessary during and after co-administration. Estrogens
For more complete data on interactions with estradiol (11 items in total), please visit the HSDB record page.

[1]. Elham Hasanzadeh. Defining the role of 17β-estradiol in human endometrial stem cells differentiation into neuron-like cells. Cell Biol Int. 2021 Jan;45(1):140-153.

[2]. Neuron-Derived Estrogen Regulates Synaptic Plasticity and Memory. J Neurosci. 2019 Apr 10;39(15):2792-2809.

Therapeutic Uses
Estradiol tablets are indicated for the treatment of moderate to severe vasomotor symptoms associated with menopause. /Included on US product label/
Estradiol tablets are indicated for the treatment of moderate to severe vulvar and vaginal atrophy symptoms associated with menopause. If used solely for the treatment of vulvar and vaginal atrophy symptoms, a vaginal topical product should be considered. /Included on US product label/
Estradiol tablets are indicated for the treatment of low estrogen levels caused by hypogonadism, castration, or primary ovarian failure. /Included on US product label/
Estradiol tablets are indicated for the treatment of appropriately screened patients with metastatic breast cancer (palliative care only). /Included on US product label/
For more complete data on the therapeutic uses of estradiol (7 types), please visit the HSDB record page.
Drug Warnings
Estrogen increases the risk of endometrial cancer—close monitoring of all women taking estrogen is crucial. For all cases of undiagnosed persistent or recurrent abnormal vaginal bleeding, adequate diagnostic measures should be taken, including endometrial sampling if necessary to rule out malignancy. There is no evidence that using “natural” estrogen results in different endometrial risks compared to using an equivalent dose of “synthetic” estrogen. Cardiovascular and other risks—Estrogen (whether or not combined with progestin) should not be used to prevent cardiovascular disease. The Women’s Health Initiative (WHI) study reported that, compared to placebo, postmenopausal women (50 to 79 years of age) treated with oral conjugated estrogen (CE 0.625 mg) combined with medroxyprogesterone acetate (MPA 2.5 mg) had an increased risk of myocardial infarction, stroke, invasive breast cancer, pulmonary embolism, and deep vein thrombosis after 5 years. The Women’s Health Initiative Memory Study (WHIMS), a sub-study of WHI, reported an increased risk of dementia in postmenopausal women aged 65 and older. Women receiving oral conjugated estrogen in combination with medroxyprogesterone acetate for 4 years were older compared to the placebo group. It is unclear whether this finding applies to younger postmenopausal women or women receiving estrogen therapy alone.
For more complete data on estradiol (48 total), please visit the HSDB record page.

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Pharmacodynamics
Estradiol acts on estrogen receptors to relieve vasomotor symptoms (such as hot flashes) and genitourinary symptoms (such as vaginal dryness and dyspareunia). Estradiol has also been shown to have a beneficial effect on bone mineral density by inhibiting bone resorption. Estrogen appears to inhibit bone resorption and may have a beneficial effect on plasma lipid profiles. Estrogen can lead to increased synthesis of several proteins in the liver, including sex hormone-binding globulin (SHBG) and thyroid-binding globulin (TBG). Estrogen is known to inhibit the production of follicle-stimulating hormone (FSH) in the anterior pituitary gland. Notes on Hypercoagulability, Cardiovascular Health, and Blood Pressure Estradiol may increase the risk of cardiovascular disease, deep vein thrombosis (DVT), and stroke, and therefore should be avoided in patients at high risk for these conditions. Estrogen can induce a hypercoagulable state, which is also associated with the use of estrogen-containing oral contraceptives (OCs) and pregnancy. Although estrogen causes elevated plasma renin and angiotensin levels. Estrogen-induced angiotensin increases can lead to sodium retention, which may be a mechanism by which hypertension occurs after oral contraceptive treatment. 17β-Estradiol (E2) is produced from androgens by aromatase. E2 is known to be produced in brain neurons, but its exact function in the brain remains unclear. This study used a forebrain neuron-specific aromatase knockout (FBN-ARO-KO) mouse model to reduce E2 derived from mouse forebrain neurons, thereby elucidating its function. Compared with the FLOX control group, FBN-ARO-KO mice showed a 70-80% reduction in aromatase and forebrain E2 levels. Male and female FBN-ARO-KO mice showed significantly reduced dendritic spine and synaptic density in the forebrain, as well as hippocampus-dependent spatial reference memory, recognition memory, and situational fear memory, but normal motor function and anxiety levels. Restoring forebrain E2 levels through in vivo administration of exogenous estradiol (E2) rescued the molecular and behavioral deficits in FBN-ARO-KO mice. Furthermore, in vitro studies using FBN-ARO-KO hippocampal sections showed that while long-term potentiation (LTP) induction was normal, its amplitude was significantly reduced. Interestingly, acute E2 treatment in vitro completely rescued LTP deficiency. Mechanistic studies revealed impaired fast kinase (AKT, ERK) and CREB-BDNF signaling pathways in the hippocampus and cerebral cortex of FBN-ARO-KO mice. Moreover, the rescue effect of acute E2 on LTP in FBN-ARO-KO hippocampal sections could be blocked by MEK/ERK inhibitors, further indicating that the fast ERK signaling pathway plays a crucial role in the neuronal E2 effect. In summary, the results suggest that neuronal-derived estradiol (E2) plays a key role in regulating synaptic plasticity and cognitive function in both male and female brains. Important statement: It is well known that the steroid hormone 17β-estradiol (E2) is produced in the female ovary. Interestingly, aromatase (the biosynthetic enzyme of E2) is also expressed in forebrain neurons, but the exact function of neuronal-derived E2 remains unclear. This study provided direct genetic evidence that neuronal-derived E2 plays a key role in regulating the rapid AKT-ERK and CREB-BDNF signaling pathways in the mouse forebrain by using a novel forebrain neuron-specific aromatase knockout mouse model to deplete neuronal-derived E2, and showed that neuronal-derived E2 is essential for the normal expression of long-term potentiation (LTP), synaptic plasticity and cognitive function in both male and female brains. These results suggest that neuronal-derived E2 acts as a novel neuromodulator in the forebrain, controlling synaptic plasticity and cognitive function. [2]

C18H24O2

272.38

272.177

C, 79.37; H, 8.88; O, 11.75

50-28-2

Alpha-Estradiol;57-91-0;Estradiol (Standard);50-28-2;Estradiol-d3;79037-37-9;Estradiol-d4;66789-03-5;Estradiol-d5;221093-45-4;Estradiol-13C2;82938-05-4;Estradiol (cypionate);313-06-4;Estradiol benzoate;50-50-0;Estradiol enanthate;4956-37-0;Estradiol hemihydrate;35380-71-3;Estradiol-d2;53866-33-4;Estradiol-13C6;Estradiol-d2-1;3188-46-3;rel-Estradiol-13C6; 979-32-8 (valerate); 113-38-2 (dipropionate); 57-63-6 (ethinyl); 172377-52-5 (sulfamate); 3571-53-7 (undecylate)

5757

White to off-white solid powder

1.2±0.1 g/cm3

445.9±45.0 °C at 760 mmHg

173ºC

209.6±23.3 °C

0.0±1.1 mmHg at 25°C

1.599

4.13

2

2

0

20

382

5

O([H])[C@@]1([H])C([H])([H])C([H])([H])[C@@]2([H])[C@]3([H])C([H])([H])C([H])([H])C4C([H])=C(C([H])=C([H])C=4[C@@]3([H])C([H])([H])C([H])([H])[C@@]21C([H])([H])[H])O[H]

VOXZDWNPVJITMN-ZBRFXRBCSA-N

InChI=1S/C18H24O2/c1-18-9-8-14-13-5-3-12(19)10-11(13)2-4-15(14)16(18)6-7-17(18)20/h3,5,10,14-17,19-20H,2,4,6-9H2,1H3/t14-,15-,16+,17+,18+/m1/s1

(8R,9S,13S,14S,17S)-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthrene-3,17-diol

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: ≥ 2.5 mg/mL (9.18 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 2.5 mg/mL (9.18 mM) in 5% DMSO + 40% PEG300 + 5% Tween80 + 50% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (9.18 mM) in 5% DMSO + 95% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 4: ≥ 2.08 mg/mL (7.64 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 5: ≥ 2.08 mg/mL (7.64 mM)(saturation unknown) in ≥ 2.5 mg/mL (5.35 mM) (add these co-solvents sequentially from left to right, and one by one),clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 6: 12.5 mg/mL (45.89 mM) in Corn Oil (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)