Dehydroepiandrosterone

Medical uses

In women with adrenal insufficiency and the healthy elderly there is insufficient evidence to support the use of DHEA.

Menopause

DHEA is sometimes used as an androgen in hormone replacement therapy (HRT) for menopause. A long-lasting ester prodrug of DHEA, prasterone enanthate, is used in combination with estradiol valerate for this indication.

Side effects

DHEA is produced naturally in the human body, but the long-term effects of its use are largely unknown. In the short term, several studies have noted few adverse effects. In a study by Chang et al., DHEA was administered at a dose of 200 mg/day for 24 weeks with slight androgenic effects noted. Another study utilized a dose up to 400 mg/day for 8 weeks with few adverse events reported. A longer term study followed patients dosed with 50 mg of DHEA for 12 months with the number and severity of side effects reported to be small. Another study delivered a dose of 50 mg of DHEA for 10 months with no serious adverse events reported.

As a hormone precursor, there has been a smattering of reports of side effects possibly caused by the hormone metabolites of DHEA.

It is not known whether DHEA is safe for long-term use. Some researchers believe DHEA supplements might actually raise the risk of breast cancer, prostate cancer, heart disease, diabetes, and stroke. DHEA may stimulate tumor growth in types of cancer that are sensitive to hormones, such as some types of breast, uterine, and prostate cancer. DHEA may increase prostate swelling in men with benign prostatic hyperplasia (BPH), an enlarged prostate gland.

DHEA is a steroid hormone. High doses may cause aggressiveness, irritability, trouble sleeping, and the growth of body or facial hair on women. It also may stop menstruation and lower the levels of HDL ("good" cholesterol), which could raise the risk of heart disease. Other reported side effects include acne, heart rhythm problems, liver problems, hair loss (from the scalp), and oily skin. It may also alter the body's regulation of blood sugar.

DHEA may promote tamoxifen resistance. Patients on hormone replacement therapy may have more estrogen-related side effects when taking DHEA. This supplement may also interfere with other medicines, and potential interactions between it and drugs and herbs are possible.

DHEA is possibly unsafe for individuals experiencing pregnancy, breast-feeding, hormone sensitive conditions, liver problems, diabetes, depression or mood disorders, polycystic ovarian syndrome (PCOS), or cholesterol problems.

Biosynthesis

DHEA is produced from cholesterol through two cytochrome P450 enzymes. Cholesterol is converted to pregnenolone by the enzyme P450 scc (side chain cleavage); then another enzyme, CYP17A1, converts pregnenolone to 17α-hydroxypregnenolone and then to DHEA.

Increasing endogenous production

Regular exercise is known to increase DHEA production in the body. Calorie restriction has also been shown to increase DHEA in primates. 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. Catalpol and a combination of acetyl-carnitine and propionyl-carnitine on 1:1 ratio also improves endogenous DHEA production and release due to direct cholinergic stimulation of CRH release and an increase of IGF-1 expression respectively.

Metabolism

Metabolites of DHEA include DHEA sulfate (DHEA-S), 7α-hydroxy-DHEA, 7β-hydroxy-DHEA, 7-keto-DHEA, 7α-hydroxyepiandrosterone, and 7β-hydroxyepiandrosterone.

Dehydroepiandrosterone sulfate

DHEA-S is the sulfate ester of DHEA. This conversion is reversibly catalyzed by sulfotransferase (SULT2A1) primarily in the adrenals, the liver, and small intestine. In the blood, most DHEA is found as DHEA-S with levels that are about 300 times higher than those of free DHEA. Orally ingested DHEA is converted to its sulfate when passing through intestines and liver. Whereas DHEA levels naturally reach their peak in the early morning hours, DHEA-S levels show no diurnal variation. From a practical point of view, measurement of DHEA-S is preferable to DHEA, as levels are more stable.

Pregnancy

During pregnancy, DHEA sulfate 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.

Measurement

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.

Androgenic activity

Although it predominantly 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 (K_i = 1 μM), weak partial agonist of the androgen receptor. 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.

Estrogenic activity

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 K_i 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. As such, it has been proposed that DHEA may be an important and potentially major endogenous estrogen in the body.

Other activity

Unlike the case of the androgen and estrogen receptors, DHEA does not bind to or activate the progesterone, glucocorticoid, or mineralocorticoid receptors.

Other nuclear receptor targets of DHEA include the PPARα, PXR, and CAR. In addition, it has been found to directly act on several membrane receptors, including the NMDA receptor as a positive allosteric modulator, the GABA_A receptor as a negative allosteric modulator, and the σ₁ receptor as an agonist. It is these actions that have conferred the label of a "neurosteroid" upon DHEA. Finally, DHEA is thought to regulate a handful of other proteins via indirect, genomic mechanisms, including the enzymes P4502C11 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 IGFBP1.

Biological function

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. 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, testosterone, and other androgens in body hair development at both adrenarche and pubarche.

As a neurosteroid, DHEA has important effects on neurological and psychological functioning.

Chemistry

DHEA is an androstane steroid and is known chemically as androst-5-en-3β-ol-17-one. It is the 5-dehydro analogue of epiandrosterone (5α-androstan-3β-ol-17-one) and is also known as 5-dehydroepiandrosterone or as δ⁵-epiandrosterone.

Isomers

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. These isomers are also technically "DHEA", since they are dehydroepiandrosterones in which hydrogens are removed from the epiandrosterone skeleton.

Dehydroandrosterone (DHA) is the 3α-epimer of DHEA and is also an endogenous androgen.

Derivatives

DHEA is used medically as the C3β esters prasterone enanthate and prasterone sodium sulfate.

United States

DHEA is legal to sell in the United States as a dietary supplement. It is currently grandfathered in as an "Old Dietary Ingredient" being on sale prior to 1994. DHEA is specifically exempted from the Anabolic Steroid Control Act of 1990 and 2004. It is banned from use in athletic competition.

Canada

In Canada, DHEA is a Controlled Drug listed under Section 23 of Schedule IV of the Controlled Drugs and Substances Act and as such is available by prescription only.

Australia

In Australia, a prescription is required to buy DHEA, where it is also comparatively expensive compared to off-the-shelf purchases in US supplement shops. Australian customs classify DHEA as an "anabolic steroid[s] or precursor[s]" and, as such, it is only possible to carry DHEA into the country through customs if one possesses an import permit which may be obtained if one has a valid prescription for the hormone.

UK

DHEA (Prasterone) is listed as an anabolic steroid and is thus a class C controlled drug.

Sports and athletics

DHEA is a prohibited substance under the World Anti-Doping Code of the World Anti-Doping Agency, which manages drug testing for Olympics and other sports. In January 2011, NBA player O.J. Mayo was given a 10-game suspension after testing positive for DHEA. Mayo termed his use of DHEA as "an honest mistake," saying the DHEA was in an over-the-counter supplement and that he was unaware the supplement was banned by the NBA. Mayo is the seventh player to test positive for performance-enhancing drugs since the league began testing in 1999. Rashard Lewis, then with the Orlando Magic, tested positive for DHEA and was suspended 10 games before the start of the 2009-10 season. 2008 Olympic 400 meter champion Lashawn Merritt has also tested positive for DHEA and was banned from the sport for 21 months. Yulia Efimova, who holds the world record pace for both the 50-meter and 200-meter breaststroke, and won the bronze medal in the 200-meter breaststroke in the 2012 London Olympic Games, tested positive for DHEA in an out-of-competition doping test. In 2016 MMA fighter Fabio Maldonado revealed he was taking DHEA during his time with the UFC.

Marketing

In the United States, DHEA or DHEA-S have been advertised with claims that they may be beneficial for a wide variety of ailments. DHEA and DHEA-S are readily available in the United States, where they are marketed as over-the-counter dietary supplements.

Research

DHEA has been studied in several conditions.

Body composition

A meta-analysis of intervention studies shows that DHEA supplementation in elderly men can induce a small but significant positive effect on body composition that is strictly dependent on DHEA conversion into its bioactive metabolites such as androgens or estrogens.

Strength

Evidence is inconclusive in regards to the effect of DHEA on strength in the elderly.

In middle-aged men, no significant effect of DHEA supplementation on lean body mass, strength, or testosterone levels was found in a randomized placebo-controlled trial.

Cancer

There is no evidence DHEA is of benefit in treating or preventing cancer. Although DHEA is postulated as an inhibitor towards glucose-6-phosphate dehydrogenase (G6PD) and suppresses leukemia cell proliferation in vitro, DHEA may enhance G6PD mRNA expression, confounding its inhibitory effects.

Cardiovascular disease

A review in 2003 found the then-extant evidence sufficient to suggest that low serum levels of DHEA-S may be associated with coronary heart disease in men, but insufficient to determine whether DHEA supplementation would have any cardiovascular benefit.

Lupus

There is some evidence of short-term benefit in those with systemic lupus erythematosus but little evidence of long-term benefit or safety.

Memory

DHEA supplementation has not been found to be useful for memory function in normal middle aged or older adults. It has been studied as a treatment for Alzheimer's disease, but there is no evidence that it is effective.

Mood

A few small, short term clinical studies have found that DHEA improves mood but its long-term efficacy and safety, and how it compares to antidepressants, was unknown as of 2015.