Diethylstilbestrol (0-100 µM) activates CatSper, enhances Ca2+ influx into human sperm, and interferes with progesterone actions in human sperm [5]. Diethylstilbestrol (0-10 µM, 1 hour) produces oxidative damage to DNA and promotes death in spermatogonial stem cells [7].

In mouse seminal vesicles, diethylstilbestrol (2 μg/day, subcutaneous injection) alters target gene methylation patterns and epigenetic modifiers (DNMT3A, MBD2, and HDAC2) while promoting ERα-mediated hormonal toxicity [3]. In rats, diethylstilbestrol (340 μg/kg, PO, every 2 days for 2 weeks) lowers corticosterone and adrenal cholesterol [4]. In adult mice, diethylstilbestrol (5 μg/kg, intraperitoneal injection) can cause thymocyte autophagy and decrease thymocyte count [6]. In both rat and human placentas, diethylstilbestrol (0.5 mg/kg, oral) lowers HSD11B2 activity [8].

Animal/Disease Models: Adult mice[6]
Doses: 5 μg/kg
Route of Administration: ip
Experimental Results: decreased number of thymocytes, and induced autophagy in thymocytes. Increased expression of Becn1, LC3 I and LC3 II.

Absorption, Distribution and Excretion
ONLY TRACES ... COULD BE FOUND IN TISSUES 24 HR AFTER ADMIN TO SHEEP & GOATS.
... SMALL AMT EXCRETED UNCHANGED. STILBESTROL LABELLED WITH (14)C IN TWO METHYLENE GROUPS, INJECTED IN SMALL DOSES INTO RATS, IS MOSTLY EXCRETED IN BILE ... ONLY 5% OF DOSE IS EXCRETED IN URINE. NO (14)CO2 IS EXCRETED IN EXPIRED AIR, SO PRESUMABLY MOLECULE IS STABLE.
DES is readily absorbed from the GI tract following oral administration. The drug is slowly inactivated in the liver and excreted in urine and feces, principally as the glucuronide.

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Metabolism / Metabolites
Hepatic.
IN SMALL DOSES, ABOUT 70% IS CONJUGATED WITH GLUCURONIC ACID AT ONE OF TWO HYDROXYL GROUPS, VERY LITTLE SULFATE CONJUGATION OCCURS, & ONLY SMALL AMT ARE EXCRETED UNCHANGED.
MAJOR METABOLITES OF DES IN SEVERAL SPECIES (RAT, MOUSE, HAMSTER, PRIMATES) ARE DIENOESTROL AND OMEGA-HYDROXYDIENOESTROL ... .
OXIDATIVE METABOLISM OF DES WAS MEASURED IN MALE & FEMALE GENITAL TRACTS OF FETAL MOUSE IN ORGAN CULTURE. MAJOR OXIDATIVE METABOLITE WAS Z,Z-DIENESTROL, WHOSE FORMATION APPEARED TO BE TIME DEPENDENT IN ISOLATED FETAL GENITAL TRACT OF BOTH SEXES. IN ADDN, FETAL GENITAL TRACTS WERE CAPABLE OF O-METHYLATION OF DES. A NEW METABOLITE, 4'-O-METHYL-DES, WAS FORMED IN FETAL GENITAL TISSUES BUT NOT IN LIVER CULTURES. CONJUGATION OF DES OCCURRED EXTENSIVELY IN FETAL LIVER & PLACENTA BUT NOT IN FETAL GENITAL TISSUES.
Microsomes were prepared from livers of untreated male hamsters (8 wk old) by differential centrifugation. Microsome-mediated reactions were carried out using 10 to 250 uM diethylstilbestrol (DES) with (0.5 to 2.0 mM) cumene hydroperoxide or 100 uM DES with 1 to 5 mM nicotinamide adenine dinucleotide phosphate. Diethylstilbestrol-4',4''-quinone formation by fetal liver homogenate was carried out by incubating 100 uM DES, 1.5 mM cumene hydroperoxide and fetal homogenate (4 mg/ml protein) for 10 min. In vitro, the time dependent formation of diethylstilbestrol-4',4''-quinone as a function of microsomal protein, cofactor or substrate concn was demonstrated. Quinone formation was time dependent and increased in linear fashion for up to 10 min, then remained at a plateau level when incubation times were further increased. Diethylstilbestrol-4',4''-quinone was also formed by fetal liver homogenate. The microsome mediated oxidation of DES to quinone was inhibited 93% by 500 uM 2(3-t-butyl-4-hydroxyanisole), 96% by 500 uM N,N,N',N'-tetramethyl-p-phenylenediamine, 83% by 500 uM n-octylamine, 97% by 500 uM potassium cyanide, and 6% by 1 mM cyclohexene oxide. In microsomal incubations with nicotinamide-adenine dinucleotide phosphate, quinone formation was below detection limits (< 0.005 nmol/mg protein/min).
For more Metabolism/Metabolites (Complete) data for DIETHYLSTILBESTROL (7 total), please visit the HSDB record page.
Hepatic.

Toxicity Summary
Estrogens diffuse into their target cells and interact with a protein receptor, the estrogen receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. The effect of Estrogen binding their receptors causes downstream increases the hepatic synthesis of sex hormone binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins and suppress follicle-stimulating hormone (FSH) from the anterior pituitary. The combination of an estrogen with a progestin suppresses the hypothalamic-pituitary system, decreasing the secretion of gonadotropin-releasing hormone (GnRH).

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Interactions
BILIARY EXCRETION OF METABOLITES OF ... STILBESTROL ... IN RATS WAS SHOWN ... TO BE INCR BY PRE-TREATMENT WITH HEPATIC-MICROSOMAL-ENZYME INDUCERS, & TO BE DECR BY ENZYME INHIBITORS AFTER DOSING WITH PARENT CMPD, BUT NO EFFECT WAS OBSERVED AFTER DOSING WITH METABOLITES.
Male and timed pregnant female Syrian hamsters received vitamin C (1% w/v) in drinking water for 4 days or 40 mg/kg alpha-naphthoflavone in corn oil by ip injection daily for 4 days. Male hamsters (1, 20, 85 or 240 days old) then received a single ip injection of diethylstilbestrol (DES, 20 mg/kg containing 250 uCi (3)H-DES). Pregnant hamsters received the same dose of DES ip on the 14th day of gestation. 30 min later animals were killed. Formation of diethylstilbestrol-4',4''-quinone occurred in all tissues investigated, livers and kidneys of male and female adult hamsters, neonates and fetuses, and in uterus and placenta. After injection of 75 umol/kg DES, diethylstilbestrol-4',4''-quinone was identified in liver and kidney extracts of male hamsters (12 wk old) at levels of 76 + or - 14 and 20 + or - 3 pmol/g tissue respectively. In neonates and fetuses, concn of diethylstilbestrol-4',4''-quinone after the same dose of DES were markedly less than those in adults (0.026 and 0.47% of adult levels in neonatal liver and kidney and 0.013 and 0.016% of adult levels in fetal liver and kidney respectively). Quinone metabolite levels were cut in half in response to vitamin C (44 to 60% of controls in kidneys and 41 to 65% of controls in livers). alpha-Naphthoflavone pretreatment decr renal and hepatic diethylstilbestrol-4',4''-quinone concn by 70 and 17% respectively.
Estrogens may interfere with the effects of bromocriptine; dosage adjustment may be necessary. /Estrogens/
Concurrent use with estrogens may increase calcium absorption and exacerbate nephrolithiasis in susceptible individuals; this can be used to therapeutic advantage to increase bone mass. /Estrogens/
For more Interactions (Complete) data for DIETHYLSTILBESTROL (11 total), please visit the HSDB record page.

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Non-Human Toxicity Values
LD50 Rat oral >3 g/kg
LD50 Rat ip 34 mg/kg
LD50 Mouse oral >3 g/kg
LD50 Mouse ip 538 mg/kg
LD50 Mouse iv 300 mg/kg

[1]. Medical conditions among adult offspring prenatally exposed to diethylstilbestrol. Epidemiology, 2013. 24(3): p. 430-8.

[2]. Kebir, O. and M.O. Krebs, Diethylstilbestrol and risk of psychiatric disorders: a critical review and new insights. World J Biol Psychiatry, 2012. 13(2): p. 84-95.

[3]. Diethylstilbestrol (DES)-stimulated hormonal toxicity is mediated by ERα alteration of target gene methylation patterns and epigenetic modifiers (DNMT3A, MBD2, and HDAC2) in the mouse seminal vesicle. Environ Health Perspect. 2014 Mar;122(3):262-8.

[4]. Diethylstilbestrol decreased adrenal cholesterol and corticosterone in rats. J Endocrinol. 2014 Apr 22;221(2):261-72.

[5]. Diethylstilbestrol activates CatSper and disturbs progesterone actions in human spermatozoa. Hum Reprod. 2017 Feb;32(2):290-298.

[6]. Diethylstilbestrol (DES) induces autophagy in thymocytes by regulating Beclin-1 expression through epigenetic modulation. Toxicology. 2018 Dec 1;410:49-58.

[7]. Diethylstilbestrol induces oxidative DNA damage, resulting in apoptosis of spermatogonial stem cells in vitro. Toxicology. 2017 May 1;382:117-121.

[8]. Diethylstilbestrol inhibits human and rat 11β-hydroxysteroid dehydrogenase 2. Endocr Connect. 2019 Jul;8(7):1061-1069.

Diethylstilbestrol (DES) can cause cancer according to California Labor Code. It can cause developmental toxicity according to state or federal government labeling requirements.
Diethylstilbestrol is an odorless tasteless white crystalline powder. (NTP, 1992)
Diethylstilbestrol is an olefinic compound that is trans-hex-3-ene in which the hydrogens at positions 3 and 4 have been replaced by p-hydroxyphenyl groups. It has a role as an antineoplastic agent, a carcinogenic agent, a xenoestrogen, an EC 3.6.3.10 (H(+)/K(+)-exchanging ATPase) inhibitor, an antifungal agent, an endocrine disruptor, an EC 1.1.1.146 (11beta-hydroxysteroid dehydrogenase) inhibitor, an autophagy inducer and a calcium channel blocker. It is a polyphenol and an olefinic compound.
A synthetic nonsteroidal estrogen used in the treatment of menopausal and postmenopausal disorders. It was also used formerly as a growth promoter in animals. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), diethylstilbestrol has been listed as a known carcinogen. (Merck, 11th ed) The FDA withdrew its approval for the use of all oral and parenteral drug products containing 25 milligrams or more of diethylstilbestrol per unit dose.
Diethylstilbestrol is a synthetic, nonsteroidal form of estrogen. A well-known teratogen and carcinogen, diethylstilbestrol inhibits the hypothalamic-pituitary-gonadal axis, thereby blocking the testicular synthesis of testosterone, lowering plasma testosterone, and inducing a chemical castration.
A synthetic nonsteroidal estrogen used in the treatment of menopausal and postmenopausal disorders. It was also used formerly as a growth promoter in animals. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), diethylstilbestrol has been listed as a known carcinogen.
A synthetic nonsteroidal estrogen used in the treatment of menopausal and postmenopausal disorders. It was also used formerly as a growth promoter in animals. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), diethylstilbestrol has been listed as a known carcinogen. (Merck, 11th ed)

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Drug Indication
Used in the treatment of prostate cancer. Previously used in the prevention of miscarriage or premature delivery in pregnant women prone to miscarriage or premature delivery.

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Mechanism of Action
Estrogens diffuse into their target cells and interact with a protein receptor, the estrogen receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. The effect of Estrogen binding their receptors causes downstream increases the hepatic synthesis of sex hormone binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins and suppress follicle-stimulating hormone (FSH) from the anterior pituitary. The combination of an estrogen with a progestin suppresses the hypothalamic-pituitary system, decreasing the secretion of gonadotropin-releasing hormone (GnRH).
The precise mechanism(s) of action of DES as a postcoital contraceptive is not fully understood; however, the drug appears to inhibit nidation (implantation) of the fertilized ovum in the endometrium when administered within 72 hours following coitus. The postcoital contraceptive activity of the drug may involve effects mediated via decreased concentrations of circulating progesterone, effects on tubal motility resulting in accelerated passage of the ovum into the uterus, and inhibition of synthesis of carbonic anhydrase in the endometrium.
... DES ... inhibited the postcastration rise in plasma FSH amd LH levels ... . In addition, DES stimulated large increases in prolactin secretion ...

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Therapeutic Uses
...DES also have been used in the treatment of prostate cancer to reduce testicular androgen production secondary to inhibition of LH release from the pituitary.
... Two major uses are as a component of combination oral contraceptives and for hormone replacement therapy in postmenopausal women. /Estrogens/
Chemotherapeutic agents useful in neoplastic disease /of the/ breast, prostate /from table/
Antineoplastic Agents, Hormonal; Carcinogens; Contraceptives, Postcoital, Synthetic; Estrogens, Non-Steroidal
For more Therapeutic Uses (Complete) data for DIETHYLSTILBESTROL (14 total), please visit the HSDB record page.

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Drug Warnings
Nausea & vomiting are an initial reaction...Fullness & tenderness of the breast & edema...Severe migraine in some...Reactivate or exacerbate endometriosis and its attendant pain. /Estrogens/
DIETHYLSTILBESTROL TAKEN DURING PREGNANCY HAS BEEN SHOWN TO BE CAUSALLY ASSOC WITH INCR IN VAGINAL AND CERVICAL CLEAR-CELL ADENOCARCINOMA IN DAUGHTERS, PRIMARILY IN THOSE BETWEEN THE AGES OF 10 AND 30 YR. THE RISK APPEARS TO BE IN THE ORDER OF 0.14-1.4/1000 EXPOSED DAUGHTERS UP TO THE AGE OF 24 YR.
VET: TOXIC EFFECTS INCLUDE THROMBOCYTOPENIA, GYNECOMASTIA, AND FLUID RETENTION.
... FIVE PATIENTS HAD SYMPTOMS OF PRESBYOPIA ASSOCIATED WITH USE OF DIETHYLSTILBESTROL & ... THESE SYMPTOMS ABATED ON DISCONTINUANCE OF DRUG.
For more Drug Warnings (Complete) data for DIETHYLSTILBESTROL (24 total), please visit the HSDB record page.

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Pharmacodynamics
Diethylstilbestrol is a synthetic estrogen that was developed to supplement a woman's natural estrogen production. In 1971, the Food and Drug Administration (FDA) issued a Drug Bulletin advising physicians to stop prescribing DES to pregnant women because it was linked to a rare vaginal cancer in female offspring.

C18H20O2

268.35

268.146

56-53-1

Diethylstilbestrol-d8;91318-10-4;Diethylstilbestrol-d3;58322-36-4

448537

White to off-white solid powder

1.1±0.1 g/cm3

407.1±25.0 °C at 760 mmHg

170-172 °C(lit.)

186.9±17.8 °C

0.0±1.0 mmHg at 25°C

1.603

5.93

2

2

4

20

286

0

CC/C(=C(/CC)\C1=CC=C(C=C1)O)/C2=CC=C(C=C2)O

RGLYKWWBQGJZGM-ISLYRVAYSA-N

InChI=1S/C18H20O2/c1-3-17(13-5-9-15(19)10-6-13)18(4-2)14-7-11-16(20)12-8-14/h5-12,19-20H,3-4H2,1-2H3/b18-17+

4-[(E)-4-(4-hydroxyphenyl)hex-3-en-3-yl]phenol

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 (9.32 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 25.0 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 2: ≥ 2.5 mg/mL (9.32 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (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 900 μL of corn oil and mix evenly.

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