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Dehydroepiandrosterone

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DHEA
Dehydroepiandrosterone

3-hydroxy-10,13-dimethyl
-1,2,3,4,7,8,9,11,12,14,15,16
-dodecahydrocyclopenta
[a]phenanthren-17-one
IUPAC name
CAS number
53-43-0
ATC code

A14AA07

PubChem
76
DrugBank
[2]
Chemical formula {{{chemical_formula}}}
Molecular weight 288.43
Bioavailability
Metabolism Hepatic
Elimination half-life 12 hours
Excretion Urinary:?%
Pregnancy category
Legal status Commercially available
(US), Rx Only (CA)
Routes of administration Oral


Dehydroepiandrosterone (DHEA), is a natural steroid prohormone produced from cholesterol by the adrenal glands, the gonads, adipose tissue, brain and in the skin (by an autocrine mechanism). DHEA is the precursor of androstenedione, which can undergo further conversion to produce the androgen testosterone and the estrogens estrone and estradiol. DHEA is also a potent sigma-1 agonist.[1]

Synonyms and brand names

Synonyms for Dehydroepiandrosterone are: Dehydroisoandrosterone; 3β-Hydroxy-5-androsten-17-one; 3β-Hydroxyandrost-5-en-17-one; Androstenol; Androstenolone; Dehydroisoandrosterone; Hydroxyandrost-5-en-17-one; Prasterone; trans-Dehydroandrosterone.

Brand names for DHEA include Prastera and Fidelin.

Dehydroepiandrosterone sulfate

Dehydroepiandrosterone sulfate (DHEAS) is the sulfated version 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 DHEAS 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, DHEAS levels show no diurnal variation. From a practical point of view, measurement of DHEAS is preferable to DHEA, as levels are more stable.

Production

DHEA1

Production of DHEA from Cholesterol

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. In humans, DHEA is the dominant steroid hormone and precursor of all sex steroids.

Role

DHEA can be understood as a prohormone for the sex steroids. DHEAS may be viewed as buffer and reservoir. Its production in the brain suggests that it also has a role as a neurosteroid.[How to reference and link to summary or text] As most DHEA is produced by the zona reticularis of the adrenal, it is argued that there is a role in the immune and stress response.[attribution needed]

As almost all DHEA is derived from the adrenal glands, blood measurements of DHEAS/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 DHEAS.

Effects and uses

Studies have shown that DHEA is useful in patients with systemic lupus erythematosus. An application of the evidence was discussed by the U.S. Food and Drug Administration in 2001 and is available online.[2] This review also shows that cholesterol and other serum lipids decrease with the use of DHEA (mainly a decrease in HDL-C and triglycerides can be expected in women, p110).

DHEA supplementation has been studied as a treatment for Alzheimer's disease, but was found to be ineffective.[3] Some small placebo-controlled randomized clinical trial studies have found long-term supplementation to improve mood and relieve depression[4][5] or to decrease insulin resistance.[6] However, a larger placebo-controlled randomized clinical trial reported in the New England Journal of Medicine in 2006 found that DHEA supplementation in elderly men and women had no beneficial effects on body composition, physical performance, insulin sensitivity, or quality of life.[7]

DHEA supplements are sometimes used as muscle-building or performance-enhancing drugs by athletes. However, a randomized placebo-controlled trial found that DHEA supplementation had no effect on lean body mass, strength, or testosterone levels.[8]

A 1986 study found that a higher level of endogenous DHEA, as determined by a single measurement, correlated with a lower risk of death or cardiovascular disease.[9] However, a more recent 2006 study found no correlation between DHEA levels and risk of cardiovascular disease or death in men.[10] A 2007 study found the DHEA restored oxidative balance in diabetic patients, reducing tissue levels of pentosidine—a biomarker for advanced glycation endproducts.[11]

Some in vitro studies have found DHEA to have an anti-proliferative or apoptotic effect on cancer cell lines.[12][13][14] The clinical significance of these findings, if any, is unknown. Higher levels of DHEA, in fact, have been correlated with an increased risk of developing breast cancer in both pre- and postmenopausal women.[15][16]

A 2002 review found that DHEA was difficult to study in an animal model. The authors concluded that there was no evidence that DHEA was beneficial for any of the conditions for which it had been studied to that point, that it was associated with significant side effects, and that based on these findings, "there is currently no scientific reason to prescribe DHEA for any purpose whatsoever."[17]

Disputed effects

In the United States, dietary supplements containing DHEA or DHEAS have been advertised with claims that they may be beneficial for a wide variety of ailments. DHEA and DHEAS are readily available in the United States, where they are regulated as foods rather than as medications. Given the lack of any proven benefit from DHEA supplementation, a 2004 review in the American Journal of Sports Medicine concluded that "The marketing of this supplement's effectiveness far exceeds its science."[18]

Contraindication

As DHEAS and DHEA are converted to sex steroids, their use is contraindicated in patients with any cancer that is estrogen- or testosterone-dependent.[How to reference and link to summary or text]

Increasing endogenous production

Regular exercise is known to increase DHEA production in the body.[19][20][21] Caloric restriction has also been shown to increase DHEA in primates.[22] Some theorize that the increase in endogenous DHEA brought about by caloric restriction is partially responsible for the longer life known to be associated with caloric restriction.[23]

Legality

United States

A bill has been introduced, in March 2007, in the U.S. Senate (S. 762) that attempts to classify DHEA as a controlled substance under the category of anabolic steroids. The sponsor is Charles Grassley (R-IA). The cosponsors are Richard Durbin (D-IL), and John McCain (R-AZ).[24]

Canada

In Canada, a prescription is required to buy DHEA.[25]

References

  1. Romieu, P., Martin-Fardon, R., Bowen, W. D., & Maurice, T. (2003). Sigma 1 Receptor-Related Neuroactive Steroids Modulate Cocaine-Induced Reward. 23(9): 3572.
  2. FDA document regading DHEA and SLE
  3. Wolkowitz OM, Kramer JH, Reus VI, et al (2003). DHEA treatment of Alzheimer's disease: a randomized, double-blind, placebo-controlled study. Neurology 60 (7): 1071-6.
  4. Wolkowitz OM, Reus VI, Keebler A, et al (1999). Double-blind treatment of major depression with dehydroepiandrosterone. The American journal of psychiatry 156 (4): 646-9.
  5. Schmidt PJ, Daly RC, Bloch M, et al (2005). Dehydroepiandrosterone monotherapy in midlife-onset major and minor depression. Arch. Gen. Psychiatry 62 (2): 154-62.
  6. Kawano H, Yasue H, Kitagawa A, et al (2003). Dehydroepiandrosterone supplementation improves endothelial function and insulin sensitivity in men. J. Clin. Endocrinol. Metab. 88 (7): 3190-5.
  7. Nair KS, Rizza RA, O'Brien P, et al (2006). DHEA in elderly women and DHEA or testosterone in elderly men. N. Engl. J. Med. 355 (16): 1647-59.
  8. Wallace MB, Lim J, Cutler A, Bucci L (1999). Effects of dehydroepiandrosterone vs androstenedione supplementation in men. Medicine and science in sports and exercise 31 (12): 1788-92.
  9. Barrett-Connor E, Khaw KT, Yen SS (1986). A prospective study of dehydroepiandrosterone sulfate, mortality, and cardiovascular disease. N. Engl. J. Med. 315 (24): 1519-24.
  10. Arnlöv J, Pencina MJ, Amin S, et al (2006). Endogenous sex hormones and cardiovascular disease incidence in men. Ann. Intern. Med. 145 (3): 176-84.
  11. Will Boggs. DHEA Restores Oxidative Balance in Type 2 Diabetes. Medscape. URL accessed on 2007-12-14.
  12. Yang NC, Jeng KC, Ho WM, Hu ML (2002). ATP depletion is an important factor in DHEA-induced growth inhibition and apoptosis in BV-2 cells. Life Sci. 70 (17): 1979-88.
  13. Schulz S, Klann RC, Schönfeld S, Nyce JW (1992). Mechanisms of cell growth inhibition and cell cycle arrest in human colonic adenocarcinoma cells by dehydroepiandrosterone: role of isoprenoid biosynthesis. Cancer Res. 52 (5): 1372-6.
  14. Loria RM (2002). Immune up-regulation and tumor apoptosis by androstene steroids. Steroids 67 (12): 953-66.
  15. Tworoger SS, Missmer SA, Eliassen AH, et al (2006). The association of plasma DHEA and DHEA sulfate with breast cancer risk in predominantly premenopausal women. Cancer Epidemiol. Biomarkers Prev. 15 (5): 967-71.
  16. Key T, Appleby P, Barnes I, Reeves G (2002). Endogenous sex hormones and breast cancer in postmenopausal women: reanalysis of nine prospective studies. J. Natl. Cancer Inst. 94 (8): 606-16.
  17. (2002) DHEA: the last elixir. Prescrire international 11 (60): 118-23.
  18. Tokish JM, Kocher MS, Hawkins RJ (2004). Ergogenic aids: a review of basic science, performance, side effects, and status in sports. The American journal of sports medicine 32 (6): 1543-53.
  19. Eur J Appl Physiol Occup Physiol 1998 Oct;78(5):466-71
  20. Eur J Appl Physiol. 2001 Jul;85(1- 2):177-84
  21. J Gerontol A Biol Sci Med Sci. 2002 Apr;57(4):B158-65
  22. Exp Gerontol. 2003 Jan-Feb; 38(1-2):35-46
  23. Roberts E. The importance of dehydroepiandrosterone sulfate in the blood of primates: a longer and healthier life? Biochem Pharmacol. 1999 Feb 15;57(4):329-46.
  24. S. 762: A bill to include dehydroepiandrosterone as an anabolic steroid, from Govtrack.us. Accessed May 9 2007.
  25. Dr. Michael Colgin. The Deal With D.H.E.A. Vista Magazine Online. www.vistamag.com [1]

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