Estrone (E1), also spelled oestrone, is a steroid, a weak estrogen, and a minor female sex hormone. It is one of three major endogenous estrogens, the others being estradiol and estriol. Estrone, as well as the other estrogens, are synthesized from cholesterol and secreted mainly from the gonads, though they can also be formed from adrenal androgens in adipose tissue. Relative to estradiol, both estrone and estriol have far weaker activity as estrogens. Estrone can be converted into estradiol, and serves mainly as a precursor or metabolic intermediate of estradiol. It is both a precursor and metabolite of estradiol.
A phytoestrogen is a plant-derived xenoestrogen not generated within the endocrine system, but consumed by eating plants or manufactured foods. Also called a "dietary estrogen", it is a diverse group of naturally occurring nonsteroidal plant compounds that, because of its structural similarity to estradiol (17-β-estradiol), have the ability to cause estrogenic or antiestrogenic effects. Phytoestrogens are not essential nutrients because their absence from the diet does not cause a disease, nor are they known to participate in any normal biological function. Common foods containing phytoestrogens are soy protein, beans, oats, barley, rice, coffee, apples, carrots.
Selective estrogen receptor modulators (SERMs), also known as estrogen receptor agonist/antagonists (ERAAs), are a class of drugs that act on estrogen receptors (ER). A characteristic that distinguishes these substances from pure ER agonists-antagonists is that their action is different in various tissues, allowing them to selectively inhibit or stimulate estrogen-like action in various tissues.
Genistein (C15H10O5) is a naturally occurring compound that structurally belongs to a class of compounds known as isoflavones. It is described as an angiogenesis inhibitor and a phytoestrogen.
Coumestrol is a natural organic compound in the class of phytochemicals known as coumestans. Coumestrol was first identified as a compound with estrogenic properties by E. M. Bickoff in ladino clover and alfalfa in 1957. It has garnered research interest because of its estrogenic activity and prevalence in some foods, including soybeans, brussels sprouts, spinach and a variety of legumes. The highest concentrations of coumestrol are found in clover, Kala Chana, and Alfalfa sprouts.
Estrone sulfate, also known as E1S, E1SO4 and estrone 3-sulfate, is a natural, endogenous steroid and an estrogen ester and conjugate.
Estetrol (E4), or oestetrol, is one of the four natural estrogenic steroid hormones found in humans, along with estrone (E1), estradiol (E2), and estriol (E3). Estetrol is a major estrogen in the body. In contrast to estrone and estradiol, estetrol is a native estrogen of fetal life. Estetrol is produced exclusively by the fetal liver and is found in detectable levels only during pregnancy, with relatively high levels in the fetus and lower levels in the maternal circulation.
Miroestrol is a phytoestrogen, a plant-derived chemical that mimics the biological activity of the hormone estrogen. Miroestrol was first reportedly isolated from the Thai herb Pueraria mirifica in 1960 and thought to be responsible for the supposed rejuvenating properties of the plant. However, more recent studies have suggested that the active ingredient may actually be the closely related chemical compound deoxymiroestrol, and the reported presence of miroestrol may only have been an artifact of the isolation procedure. When deoxymiroestrol is exposed to the oxygen in air, it is converted to miroestrol.
Estradiol dipropionate (EDP), sold under the brand names Agofollin, Di-Ovocylin, and Progynon DP among others, is an estrogen medication which has been used in hormone therapy for menopausal symptoms and low estrogen levels in women and in the treatment of gynecological disorders. It has also been used in feminizing hormone therapy for transgender women and in the treatment of prostate cancer in men. Although widely used in the past, estradiol dipropionate has largely been discontinued and is mostly no longer available today. It appears to remain in use only in Japan, Macedonia, and Australia. Estradiol dipropionate is given by injection into muscle at intervals ranging from once or twice a week to once every week and a half to two weeks.
8-Prenylnaringenin (8-PN; also known as flavaprenin, (S)-8-dimethylallylnaringenin, hopein, or sophoraflavanone B) is a prenylflavonoid phytoestrogen. It is reported to be the most estrogenic phytoestrogen known. The compound is equipotent at the two forms of estrogen receptors, ERα and ERβ, and it acts as a full agonist of ERα. Its effects are similar to those of estradiol, but it is considerably less potent in comparison.
Neurodegenerative diseases can disrupt the normal human homeostasis and result in abnormal estrogen levels. For example, neurodegenerative diseases can cause different physiological effects in males and females. In particular, estrogen studies have revealed complex interactions with neurodegenerative diseases. Estrogen was initially proposed to be a possible treatment for certain types of neurodegenerative diseases but a plethora of harmful side effects such as increased susceptibility to breast cancer and coronary heart disease overshadowed any beneficial outcomes. On the other hand, Estrogen Replacement Therapy has shown some positive effects with postmenopausal women. Estrogen and estrogen-like molecules form a large family of potentially beneficial alternatives that can have dramatic effects on human homeostasis and disease. Subsequently, large-scale efforts were initiated to screen for useful estrogen family molecules. Furthermore, scientists discovered new ways to synthesize estrogen-like compounds that can avoid many side effects.
17α-Estradiol is a minor and weak endogenous steroidal estrogen that is related to 17β-estradiol. It is the C17 epimer of estradiol. It has approximately 100-fold lower estrogenic potency than 17β-estradiol. The compound shows preferential affinity for the ERα over the ERβ. Although 17α-estradiol is far weaker than 17β-estradiol as an agonist of the nuclear estrogen receptors, it has been found to bind to and activate the brain-expressed ER-X with a greater potency than that of 17β-estradiol, suggesting that it may be the predominant endogenous ligand for the receptor.
Conjugated estrogens (CEs), or conjugated equine estrogens (CEEs), sold under the brand name Premarin among others, is an estrogen medication which is used in menopausal hormone therapy and for various other indications. It is a mixture of the sodium salts of estrogen conjugates found in horses, such as estrone sulfate and equilin sulfate. CEEs are available in the form of both natural preparations manufactured from the urine of pregnant mares and fully synthetic replications of the natural preparations. They are formulated both alone and in combination with progestins such as medroxyprogesterone acetate. CEEs are usually taken by mouth, but can also be given by application to the skin or vagina as a cream or by injection into a blood vessel or muscle.
Estrin, or oestrin, also known as estra-1,3,5(10)-triene, is an estrane steroid. It is dehydrogenated estrane with double bonds specifically at the C1, C3, and C5(10) positions. Estrin is a parent structure of the estrogen steroid hormones estradiol, estrone, and estriol, which have also been known as dihydroxyestrin, ketohydroxyestrin, and trihydroxyestrin, respectively.
The hydroxylation of estradiol is one of the major routes of metabolism of the estrogen steroid hormone estradiol. It is hydroxylated into the catechol estrogens 2-hydroxyestradiol and 4-hydroxyestradiol and into estriol (16α-hydroxyestradiol), reactions which are catalyzed by cytochrome P450 enzymes predominantly in the liver, but also in various other tissues.
Estrone (E1), sold under the brand names Estragyn, Kestrin, and Theelin among many others, is an estrogen medication and naturally occurring steroid hormone which has been used in menopausal hormone therapy and for other indications. It has been provided as an aqueous suspension or oil solution given by injection into muscle and as a vaginal cream applied inside of the vagina. It can also be taken by mouth as estradiol/estrone/estriol and in the form of prodrugs like estropipate and conjugated estrogens.
The pharmacology of estradiol, an estrogen medication and naturally occurring steroid hormone, concerns its pharmacodynamics, pharmacokinetics, and various routes of administration.
Soy boy is a pejorative term sometimes used in online communities to describe men perceived to be lacking masculine characteristics. The term bears many similarities and has been compared to the slang terms cuck, nu-male and low-T – terms sometimes used as insults for male femininity by online communities.
17α-Ethynyl-3β-androstanediol is a synthetic estrogen and a 17α-substituted derivative of 3β-androstanediol which was never marketed.
11β-Chloromethylestradiol is a synthetic steroidal estrogen which was never marketed. It has very high affinity for the estrogen receptor and dissociates from it relatively slowly. It was originally thought that 11β-CME2 might be a covalent ligand of the estrogen receptors, but its binding was subsequently shown to be fully reversible. The relative binding affinity of 11β-CME2 for the estrogen receptors ranges from 230 to 3,320% of that of estradiol depending on the study. 11β-CME2 also has about 14% of the relative binding affinity of estradiol for sex hormone-binding globulin (SHBG). The compound has been developed as a radiolabel for the ERs.
