Names | |
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IUPAC name 3β-Hydroxyandrost-5-en-17-one | |
Systematic IUPAC name (3aS,3bR,7S,9aR,9bS,11aS)-7-Hydroxy-9a,11a-dimethyl-2,3,3a,3b,4,6,7,8,9,9a,9b,10,11,11a-tetradecahydro-1H-cyclopenta[a]phenanthren-1-one | |
Other names Androstenolone; Prasterone; Androst-5-en-3β-ol-17-one; 5,6-Didehydroepiandrosterone; [1] Dehydroisoepiandrosterone | |
Identifiers | |
3D model (JSmol) | |
ChEBI | |
ChEMBL | |
ChemSpider | |
DrugBank | |
ECHA InfoCard | 100.000.160 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C19H28O2 | |
Molar mass | 288.424 g/mol |
Melting point | 148.5 |
Pharmacology | |
QA14AA07 ( WHO ) G03EA03 ( WHO ) (combination with estrogen) | |
By mouth, vaginal (insert), intramuscular injection (as prasterone enanthate), injection (as prasterone sodium sulfate) | |
Pharmacokinetics: | |
50% [2] | |
Hepatic [2] | |
DHEA: 25 minutes [3] DHEA-S: 11 hours [3] | |
Urine | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Dehydroepiandrosterone (DHEA), also known as androstenolone, is an endogenous steroid hormone precursor. [4] It is one of the most abundant circulating steroids in humans. [5] DHEA is produced in the adrenal glands, [6] the gonads, and the brain. [7] It functions as a metabolic intermediate in the biosynthesis of the androgen and estrogen sex steroids both in the gonads and in various other tissues. [4] [8] [9] However, DHEA also has a variety of potential biological effects in its own right, binding to an array of nuclear and cell surface receptors, [10] and acting as a neurosteroid and modulator of neurotrophic factor receptors. [11]
In the United States, DHEA is sold as an over-the-counter supplement, and medication called prasterone.
DHEA and other adrenal androgens such as androstenedione, although relatively weak androgens, are responsible for the androgenic effects of adrenarche, such as early pubic and axillary hair growth, adult-type body odor, increased oiliness of hair and skin, and mild acne. [12] [13] [14] DHEA is potentiated locally via conversion into testosterone and dihydrotestosterone (DHT) in the skin and hair follicles. [4] Women with complete androgen insensitivity syndrome (CAIS), who have a non-functional androgen receptor (AR) and are immune to the androgenic effects of DHEA and other androgens, have absent or only sparse/scanty pubic and axillary hair and body hair in general, demonstrating the role of DHEA and other androgens in body hair development at both adrenarche and pubarche. [15] [16] [17] [18]
DHEA is a weak estrogen. [4] [10] [19] In addition, it is transformed into potent estrogens such as estradiol in certain tissues such as the vagina, and thereby produces estrogenic effects in such tissues. [4]
As a neurosteroid and neurotrophin, DHEA has important effects in the central nervous system. [20] [21] [22]
Although it functions as an endogenous precursor to more potent androgens such as testosterone and DHT, DHEA has been found to possess some degree of androgenic activity in its own right, acting as a low affinity (Ki = 1 μM), weak partial agonist of the androgen receptor (AR). However, its intrinsic activity at the receptor is quite weak, and on account of that, due to competition for binding with full agonists like testosterone, it can actually behave more like an antagonist depending on circulating testosterone and dihydrotestosterone (DHT) levels, and hence, like an antiandrogen. However, its affinity for the receptor is very low, and for that reason, is unlikely to be of much significance under normal circumstances. [19] [23]
In addition to its affinity for the androgen receptor, DHEA has also been found to bind to (and activate) the ERα and ERβ estrogen receptors with Ki values of 1.1 μM and 0.5 μM, respectively, and EC50 values of >1 μM and 200 nM, respectively. Though it was found to be a partial agonist of the ERα with a maximal efficacy of 30–70%, the concentrations required for this degree of activation make it unlikely that the activity of DHEA at this receptor is physiologically meaningful. Remarkably however, DHEA acts as a full agonist of the ERβ with a maximal response similar to or actually slightly greater than that of estradiol, and its levels in circulation and local tissues in the human body are high enough to activate the receptor to the same degree as that seen with circulating estradiol levels at somewhat higher than their maximal, non-ovulatory concentrations; indeed, when combined with estradiol with both at levels equivalent to those of their physiological concentrations, overall activation of the ERβ was doubled. [10] [19]
DHEA does not bind to or activate the progesterone, glucocorticoid, or mineralocorticoid receptors. [19] [24] Other nuclear receptor targets of DHEA besides the androgen and estrogen receptors include the PPARα, PXR, and CAR. [25] However, whereas DHEA is a ligand of the PPARα and PXR in rodents, it is not in humans. [26] In addition to direct interactions, DHEA is thought to regulate a handful of other proteins via indirect, genomic mechanisms, including the enzymes CYP2C11 and 11β-HSD1 – the latter of which is essential for the biosynthesis of the glucocorticoids such as cortisol and has been suggested to be involved in the antiglucocorticoid effects of DHEA – and the carrier protein IGFBP1. [19] [27]
DHEA has been found to directly act on several neurotransmitter receptors, including acting as a positive allosteric modulator of the NMDA receptor, as a negative allosteric modulator of the GABAA receptor, and as an agonist of the σ1 receptor. [28] [25]
In 2011, the surprising discovery was made that DHEA, as well as its sulfate ester, DHEA-S, directly bind to and activate TrkA and p75NTR, receptors of neurotrophins like nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), with high affinity. [25] [29] DHEA was subsequently also found to bind to TrkB and TrkC with high affinity, though it only activated TrkC not TrkB. [25] [30] DHEA and DHEA-S bound to these receptors with affinities in the low nanomolar range (around 5 nM), which were nonetheless approximately two orders of magnitude lower relative to highly potent polypeptide neurotrophins like NGF (0.01–0.1 nM). [25] [29] [30] In any case, DHEA and DHEA-S both circulate at requisite concentrations to activate these receptors and were thus identified as important endogenous neurotrophic factors. [25] [29] They have since been labeled "steroidal microneurotrophins", due to their small-molecule and steroidal nature relative to their polypeptide neurotrophin counterparts. [31] Subsequent research has suggested that DHEA and/or DHEA-S may in fact be phylogenetically ancient "ancestral" ligands of the neurotrophin receptors from early on in the evolution of the nervous system. [25] [30] The findings that DHEA binds to and potently activates neurotrophin receptors may explain the positive association between decreased circulating DHEA levels with age and age-related neurodegenerative diseases. [25] [29]
Similarly to pregnenolone, its synthetic derivative 3β-methoxypregnenolone (MAP-4343), and progesterone, DHEA has been found to bind to microtubule-associated protein 2 (MAP2), specifically the MAP2C subtype (Kd = 27 μM). [25] However, it is unclear whether DHEA increases binding of MAP2 to tubulin like pregnenolone. [25]
Some research has shown that DHEA levels are too low in people with ADHD, and treatment with methylphenidate or bupropion (stimulant type of medications) normalizes DHEA levels. [32]
DHEA is an uncompetitive inhibitor of G6PDH (Ki = 17 μM; IC50 = 18.7 μM), and is able to lower NADPH levels and reduce NADPH-dependent free radical production. [33] [34] It is thought that this action may possibly be responsible for much of the antiinflammatory, antihyperplastic, chemopreventative, antihyperlipidemic, antidiabetic, and antiobesic, as well as certain immunomodulating activities of DHEA (with some experimental evidence to support this notion available). [33] [34] [35] [36] However, it has also been said that inhibition of G6PDH activity by DHEA in vivo has not been observed and that the concentrations required for DHEA to inhibit G6PDH in vitro are very high, thus making the possible contribution of G6PDH inhibition to the effects of DHEA uncertain. [34]
DHEA supplements have been promoted in supplement form for its claimed cancer prevention properties; there is no scientific evidence to support these claims. [37]
DHEA is produced in the zona reticularis of the adrenal cortex under the control of adrenocorticotropic hormone (ACTH) and by the gonads under the control of gonadotropin-releasing hormone (GnRH). [39] [40] It is also produced in the brain. [41] DHEA is synthesized from cholesterol via the enzymes cholesterol side-chain cleavage enzyme (CYP11A1; P450scc) and 17α-hydroxylase/17,20-lyase (CYP17A1), with pregnenolone and 17α-hydroxypregnenolone as intermediates. [42] It is derived mostly from the adrenal cortex, with only about 10% being secreted from the gonads. [43] [44] [45] Approximately 50 to 70% of circulating DHEA originates from desulfation of DHEA-S in peripheral tissues. [43] DHEA-S itself originates almost exclusively from the adrenal cortex, with 95 to 100% being secreted from the adrenal cortex in women. [39] [45]
Regular exercise is known to increase DHEA production in the body. [46] [47] Calorie restriction has also been shown to increase DHEA in primates. [48] Some theorize that the increase in endogenous DHEA brought about by calorie restriction is partially responsible for the longer life expectancy known to be associated with calorie restriction. [49]
In the circulation, DHEA is mainly bound to albumin, with a small amount bound to sex hormone-binding globulin (SHBG). [50] [51] The small remainder of DHEA not associated with albumin or SHBG is unbound and free in the circulation. [50]
DHEA easily crosses the blood–brain barrier into the central nervous system. [41]
DHEA is transformed into DHEA-S by sulfation at the C3β position via the sulfotransferase enzymes SULT2A1 and to a lesser extent SULT1E1. [42] [52] [53] This occurs naturally in the adrenal cortex and during first-pass metabolism in the liver and intestines when exogenous DHEA is administered orally. [52] Levels of DHEA-S in circulation are approximately 250 to 300 times those of DHEA. [20] DHEA-S in turn can be converted back into DHEA in peripheral tissues via steroid sulfatase (STS). [54] [55]
The terminal half-life of DHEA is short at only 15 to 30 minutes. [56] In contrast, the terminal half-life of DHEA-S is far longer, at 7 to 10 hours. [56] As DHEA-S can be converted back into DHEA, it serves as a circulating reservoir for DHEA, thereby extending the duration of DHEA. [57] [20]
Metabolites of DHEA include DHEA-S, 7α-hydroxy-DHEA, 7β-hydroxy-DHEA, 7-keto-DHEA, 7α-hydroxyepiandrosterone, and 7β-hydroxyepiandrosterone, as well as androstenediol and androstenedione. [8]
During pregnancy, DHEA-S is metabolized into the sulfates of 16α-hydroxy-DHEA and 15α-hydroxy-DHEA in the fetal liver as intermediates in the production of the estrogens estriol and estetrol, respectively. [58]
Prior to puberty in humans, DHEA and DHEA-S levels elevate upon differentiation of the zona reticularis of the adrenal cortex. [25] Peak levels of DHEA and DHEA-S are observed around age 20, which is followed by an age-dependent decline throughout life eventually back to prepubertal concentrations. [25] Plasma levels of DHEA in adult men are 10 to 25 nM, in premenopausal women are 5 to 30 nM, and in postmenopausal women are 2 to 20 nM. [25] Conversely, DHEA-S levels are an order of magnitude higher at 1–10 μM. [25] Levels of DHEA and DHEA-S decline to the lower nanomolar and micromolar ranges in men and women aged 60 to 80 years. [25]
DHEA levels are as follows: [59]
As almost all DHEA is derived from the adrenal glands, blood measurements of DHEA-S/DHEA are useful to detect excess adrenal activity as seen in adrenal cancer or hyperplasia, including certain forms of congenital adrenal hyperplasia. Women with polycystic ovary syndrome tend to have elevated levels of DHEA-S. [60]
DHEA, also known as androst-5-en-3β-ol-17-one, is a naturally occurring androstane steroid and a 17-ketosteroid. [61] It is closely related structurally to androstenediol (androst-5-ene-3β,17β-diol), androstenedione (androst-4-ene-3,17-dione), and testosterone (androst-4-en-17β-ol-3-one). [61] DHEA is the 5-dehydro analogue of epiandrosterone (5α-androstan-3β-ol-17-one) and is also known as 5-dehydroepiandrosterone or as δ5-epiandrosterone. [61]
The term "dehydroepiandrosterone" is ambiguous chemically because it does not include the specific positions within epiandrosterone at which hydrogen atoms are missing. DHEA itself is 5,6-didehydroepiandrosterone or 5-dehydroepiandrosterone. A number of naturally occurring isomers also exist and may have similar activities. Some isomers of DHEA are 1-dehydroepiandrosterone (1-androsterone) and 4-dehydroepiandrosterone. [62] These isomers are also technically "DHEA", since they are dehydroepiandrosterones in which hydrogens are removed from the epiandrosterone skeleton.[ citation needed ]
Dehydroandrosterone (DHA) is the 3α-epimer of DHEA and is also an endogenous androgen.
DHEA was first isolated from human urine in 1934 by Adolf Butenandt and Kurt Tscherning. [63]
An androgen is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes the embryological development of the primary male sex organs, and the development of male secondary sex characteristics at puberty. Androgens are synthesized in the testes, the ovaries, and the adrenal glands.
Progestogens, also sometimes written progestins, progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestogen in the body. The progestogens are named for their function in maintaining pregnancy, although they are also present at other phases of the estrous and menstrual cycles.
The adrenal cortex is the outer region and also the largest part of the adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. It is also a secondary site of androgen synthesis.
Androstenedione, or 4-androstenedione, also known as androst-4-ene-3,17-dione, is an endogenous weak androgen steroid hormone and intermediate in the biosynthesis of estrone and of testosterone from dehydroepiandrosterone (DHEA). It is closely related to androstenediol (androst-5-ene-3β,17β-diol).
Estriol (E3), also spelled oestriol, 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 estrone. Levels of estriol in women who are not pregnant are almost undetectable. However, during pregnancy, estriol is synthesized in very high quantities by the placenta and is the most produced estrogen in the body by far, although circulating levels of estriol are similar to those of other estrogens due to a relatively high rate of metabolism and excretion. Relative to estradiol, both estriol and estrone have far weaker activity as estrogens.
Adrenarche is an early stage in sexual maturation that happens in some higher primates, typically peaks at around 20 years of age, and is involved in the development of pubic hair, body odor, skin oiliness, axillary hair, sexual attraction/sexual desire/increased libido and mild acne. During adrenarche the adrenal glands secrete increased levels of weak adrenal androgens, including dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), and androstenedione (A4), but without increased cortisol levels. Adrenarche is the result of the development of a new zone of the adrenal cortex, the zona reticularis. Adrenarche is a process related to puberty, but distinct from hypothalamic–pituitary–gonadal axis maturation and function.
Pregnenolone (P5), or pregn-5-en-3β-ol-20-one, is an endogenous steroid and precursor/metabolic intermediate in the biosynthesis of most of the steroid hormones, including the progestogens, androgens, estrogens, glucocorticoids, and mineralocorticoids. In addition, pregnenolone is biologically active in its own right, acting as a neurosteroid.
Prasterone, also known as dehydroepiandrosterone (DHEA) and sold under the brand name Intrarosa among others, is a medication as well as over-the-counter dietary supplement which is used to correct DHEA deficiency due to adrenal insufficiency or old age, as a component of menopausal hormone therapy, to treat painful sexual intercourse due to vaginal atrophy, and to prepare the cervix for childbirth, among other uses. It is taken by mouth, by application to the skin, in through the vagina, or by injection into muscle.
Dehydroepiandrosterone sulfate, abbreviated as DHEA sulfate or DHEA-S, also known as androstenolone sulfate, is an endogenous androstane steroid that is produced by the adrenal cortex. It is the 3β-sulfate ester and a metabolite of dehydroepiandrosterone (DHEA) and circulates in far greater relative concentrations than DHEA. The steroid is hormonally inert and is instead an important neurosteroid and neurotrophin.
Estrone sulfate, also known as E1S, E1SO4 and estrone 3-sulfate, is a natural, endogenous steroid and an estrogen ester and conjugate.
Étienne-Émile Baulieu is a French biochemist and endocrinologist who is best known for his research in the field of steroid hormones and their role in reproduction and aging.
3β-Androstanediol, also known as 5α-androstane-3β,17β-diol, and sometimes shortened in the literature to 3β-diol, is an endogenous steroid hormone and a metabolite of androgens like dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT).
A neurosteroidogenesis inhibitor is a drug that inhibits the production of endogenous neurosteroids. Neurosteroids include the excitatory neurosteroids pregnenolone sulfate, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S), and the inhibitory neurosteroids allopregnanolone, tetrahydrodeoxycorticosterone (THDOC), and 3α-androstanediol, among others. By inhibiting the synthesis of endogenous neurosteroids, neurosteroidogenesis inhibitors have effects in the central nervous system.
A steroidogenesis inhibitor, also known as a steroid biosynthesis inhibitor, is a type of drug which inhibits one or more of the enzymes that are involved in the process of steroidogenesis, the biosynthesis of endogenous steroids and steroid hormones. They may inhibit the production of cholesterol and other sterols, sex steroids such as androgens, estrogens, and progestogens, corticosteroids such as glucocorticoids and mineralocorticoids, and neurosteroids. They are used in the treatment of a variety of medical conditions that depend on endogenous steroids.
Prasterone enanthate, also known as dehydroepiandrosterone enanthate (DHEA-E) and sold in combination with estradiol valerate under the brand name Gynodian Depot among others, is a weak androgen, estrogen, and neurosteroid medication which is used as a component of menopausal hormone therapy to treat menopausal symptoms in women. It is available only as an injectable preparation in combination with estradiol valerate. The medication is given by injection into muscle typically once every 4 weeks.
7α-Hydroxydehydroepiandrosterone, also known as 3β,7α-dihydroxyandrost-5-ene-17-one, is an endogenous, naturally occurring steroid and a major metabolite of dehydroepiandrosterone (DHEA) that is formed by CYP7B1 in tissues such as the prostate gland and by CYP3A4 in the liver. The major metabolic pathway of DHEA outside the liver is via 7-hydroxylation into 7α-OH-DHEA and 7β-OH-DHEA. 7α-OH-DHEA has weak estrogenic activity, selectively activating the estrogen receptor ERβ. In addition, 7α-OH-DHEA may be responsible for the known antiglucocorticoid effects of DHEA.
Adrenal steroids are steroids that are derived from the adrenal glands. They include corticosteroids, which consist of glucocorticoids like cortisol and mineralocorticoids like aldosterone, adrenal androgens like dehydroepiandrosterone (DHEA), DHEA sulfate (DHEA-S), and androstenedione (A4), and neurosteroids like DHEA and DHEA-S, as well as pregnenolone and pregnenolone sulfate (P5-S). Adrenal steroids are specifically produced in the adrenal cortex.
BNN-20, also known as 17β-spiro-(androst-5-en-17,2'-oxiran)-3β-ol, is a synthetic neurosteroid, "microneurotrophin", and analogue of the endogenous neurosteroid dehydroepiandrosterone (DHEA). It acts as a selective, high-affinity, centrally active agonist of the TrkA, TrkB, and p75NTR, receptors for the neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), as well as for DHEA and DHEA sulfate (DHEA-S). The drug has been suggested as a potential novel treatment for Parkinson's disease and other conditions.
BNN-27, also known as 17α,20R-epoxypregn-5-ene-3β,21-diol, is a synthetic neurosteroid and "microneurotrophin" and analogue of the endogenous neurosteroid dehydroepiandrosterone (DHEA). It acts as a selective, high-affinity, centrally active agonist of the TrkA and p75NTR, receptors for nerve growth factor (NGF) and other neurotrophins, as well as for DHEA and DHEA sulfate (DHEA-S). BNN-27 has neuroprotective and neurogenic effects and has been suggested as a potential novel treatment for neurodegenerative diseases and brain trauma.
Adrenopause is the decline in secretion and levels of adrenal androgens such as dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) from the zona reticularis of the adrenal glands with age. Levels of adrenal androgens start to increase around age 7 or 8 years (adrenarche), peak in early adulthood around age 20 to 25 years, and decrease at a rate of approximately 2% per year thereafter, eventually reaching levels of 10 to 20% of those of young adults by age 80 years. It is caused by the progressive apoptosis of adrenal androgen-secreting cells and hence involution of the zona reticularis. It is analogous to andropause in men and menopause in women, the abrupt or gradual decline in production of sex hormones from the gonads with age.
DHEA (Dehydroepiandrosterone) is a common hormone produced in the adrenal glands, the gonads, and the brain.