Androstenedione

(biochemistry) C₁₉H₂₆O₂ Any one of three isomeric androgens produced by the adrenal cortex.

Brand names: Andro-Max™, Androstat™ 100

Last updated: 7/1/2002

Important Disclaimer: The drug information provided here is for educational purposes only. It is intended to supplement, not substitute for, the diagnosis, treatment and advice of a medical professional. This drug information does not cover all possible uses, precautions, side effects and interactions. It should not be construed to indicate that this or any drug is safe for you. Consult your medical professional for guidance before using any prescription or over the counter drugs.

Description

Androstenedione is a hormone that occurs naturally in the body, and is one of those responsible for male characteristics. It is a metabolite of DHEA, and as such, a direct precursor to the male hormone testosterone. It is found in some plant matter, notably pollen, and in the gonads of all mammals.

General Use

Supplementation with androstenedione increases blood levels of testosterone, which among other things, will lead to an increase in strength and muscle mass. As such, it is mainly of interest to athletes and bodybuilders, for whom it has the added benefits of increasing energy levels, improving levels of nitrogen retention and shortening muscle recovery time. Androstenedione is safer than anabolic steroids because it has a far gentler effect on the body, and potential effects are milder and more transient.

Androstenedione is also taken to improve well being, and to raise levels of mental alertness. In addition, it is thought to have a positive effect on sexual performance. As androstenedione also aids in the conversion of fatty tissue to muscle, it could conceivably be considered an aid to weight loss.

The German patent for androstenedione states that 50 mg administered orally raised testosterone levels from 140–183% above normal, which although impressive, is considerably less than the increase associated with administration of anabolic steroids. Also, it is a precursor, in that the body retains some control over production of testosterone.

Preparations

When taken orally, androstenedione is metabolized by a single enzyme into testosterone. Athletes generally take between 50–300 mg daily, according to how much time is spent exercising and how much physical improvement is required. Dosage is usually sublingual in the form of a spray or capsules. The spray is felt to be far more effective, due to imperfect absorption through the digestive route.

Levels of testosterone in the blood will begin to rise approximately 15 minutes after administration of androstenedione supplements. They will remain so for about three hours, with testosterone levels peaking roughly 1–1.5 hours after administration.

Precautions

There is, as of July 2000, no reliable research to prove the claims by supplement companies that androstenedione is useful. Trials that have been conducted are limited in size and scope, and generally do not satisfy the criteria set for medical trials. Some experts warn that as a result of the short time that androstenedione stays in the system, it is unlikely to have any significant bodybuilding effects.

Androstenedione is not suitable for pregnant or lactating women, and should not be taken at all by children. When taken by women, this supplement may cause hirsuitism and virilization. Caution should be exercised when males under the age of 25 years take androstenedione.

Those supplementing with androstenedione on a regular basis are advised to have "cool down" periods when the product is not taken. This can either be a couple of days a week, or one week per month.

Androstenedione is unsuitable for use by men with prostate cancer or elevated PSA. It may also stimulate prostate replication, enlarging the prostrate (benign prostate hypertrophy or cancer). Many experts are skeptical of the claims made by supplement companies, because they say that natural bodily checks and balances will work against this supplement to ensure that muscle mass and strength do not exceed normal levels for the individual. Taking androstenedione at times other than periods of physical exertion is not recommended, because of the possible effect on mood.

Because of the complex interaction of hormones within the body, it is strongly advised that anyone contemplating supplementing with androstenedione consult a qualified practitioner.

Whereas anabolic steroids are illegal, androstenedione is considered a dietary supplement, and as such is not governed by the same regulations.

As a result of trials conducted by them, the American Medical Association issued a statement to the effect that androstenedione does not raise serum testosterone levels, and in addition, it may have undesirable side effects.

Side Effects

Possible effects on the personality of this type of hormone should be considered, as high levels of male hormones have been known to trigger aggressive behavior in some cases, particularly when high doses of the supplement are involved.

It is also possible that long-term use of androstenedione, which is not in accordance with medical recommendations, may eventually have a negative effect on natural levels of testosterone, due to compensation on the part of the pituitary gland. This means that, in the long term, it is possible that supplementation with androstenedione may cause a reduction in levels of testosterone.

The androgen effect of androstenedione may cause males to develop loss of head hair. Other side effects that have been associated with androstenedione administration include blurred vision, development of breast-like tissue, and the development of acne.

Interactions

This supplement should not be taken in conjunction with other bodybuilding substances, particularly anabolic steroids, unless under the direction of a physician. Lysophosphatidyl choline, when taken in conjunction with androstenedione, may enhance absorption.

In addition, manufacturers recommend saw palmetto to be taken in conjunction with androstenedione as it can help reduce associated hair loss, and is useful in controlling prostate enlargement.

Resources

Other

Betterbodz (1995-2000). [cited December 28, 2000].

Nutritionalsupplements.com (1998-2000). [cited December 28, 2000].

[Article by: Patricia Skinner]

A natural prohormone found in both males and females. Androstenedione is a precursor of testosterone. Synthetic forms of androstenedione are available as training supplements. However, in 2004 the US Food and Drug Administration (FDA) requested companies to cease producing supplements containing androstenedione because the FDA concluded that there is inadequate information to establish that a dietary supplement containing androstenedione will reasonably be expected to be safe, and that these products may increase the risk of serious health problems because they are converted in the body to testosterone, which is an androgenic and anabolic steroid. In the USA, the Anabolic Steroid Control Act, signed into law in October 2004, classifies androstenedione and 17 other steroids as controlled substances. As of January 2005, these substances may not be sold without prescription. Several sports organizations, including the World Anti-Doping Agency have banned use of androstenedione.

An androgenic steroid produced by the testis, adrenal cortex and ovary. Immunization against it gives excellent results in promoting fertility in ewes by increasing the twinning rate.

This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (April 2008)

Androstenedione
Systematic (IUPAC) name
4-Androstene-3,17-dione
Identifiers
CAS number	63-05-8
ATC code	none
PubChem	6128
ChemSpider	5898
Chemical data
Formula	C19H26O2
Mol. mass	286.4
SMILES	eMolecules & PubChem
Pharmacokinetic data
Bioavailability	?
Metabolism	Liver
Half life	?
Excretion	?
Therapeutic considerations
Pregnancy cat.	?
Legal status	Schedule III (US)
Routes	?
Y(what is this?)  (verify)

Androstenedione (also known as 4-androstenedione) is a 19-carbon steroid hormone produced in the adrenal glands and the gonads as an intermediate step in the biochemical pathway that produces the androgen testosterone and the estrogens estrone and estradiol.

Contents 1 Synthesis 2 Endocrine function 3 Androstenedione as a supplement 3.1 History 3.2 Biological Effects 4 Additional images 5 References

Synthesis

Steroidogenesis. Androstenedione is at center.

Androstenedione is the common precursor of male and female sex hormones. Some androstenedione is also secreted into the plasma, and may be converted in peripheral tissues to testosterone and estrogens.

Androstenedione originates either from the conversion of dehydroepiandrosterone or from 17-hydroxyprogesterone. Conversion of dehydroepiandrosterone to androstenedione requires 3Beta Hydroxysteroid dehydrogenase. 17-hydroxyprogesterone, on the other hand, requires 17,20 lyase for its synthesis. Thus, both reactions that produce androstenedione directly or indirectly depend on 17,20 lyase.

Androstenedione is further converted to either testosterone or estrogen. Conversion of androstenedione to testosterone requires the enzyme 17β-hydroxysteroid dehydrogenase, while conversion of androstenedione to estrogen (e.g. estrone and estradiol) requires the enzyme aromatase.

The production of adrenal androstenedione is governed by ACTH, whereas production of gonadal androstenedione is under control by gonadotropins. In premenopausal women, the adrenal glands and ovaries each produce about half of the total androstendione (about 3 mg/day). After menopause, androstenedione production is about halved, primarily due to the reduction of the steroid secreted by the ovary. Nevertheless, androstenedione is the principal steroid produced by the postmenopausal ovary.

Endocrine function

In females, androstenedione is released into the blood by theca cells. The function of this is to provide androstenedione substrate for estrogen production in granulosa cells, since these cells lack 17,20 lyase required for androstenedione. Similarly, theca cells lack the enzyme aromatase required to make estrogens themselves. Thus, theca cells and granulosa cells work together to form estrogen.^[1]

Androstenedione as a supplement

History

Androstenedione was manufactured as a dietary supplement, often called andro (or andros) for short. Sports Illustrated credits Patrick Arnold for introducing androstenedione to the North American market.^[2] Andro was legal and able to be purchased over the counter and consequently it was common use in Major League Baseball throughout the 1990s by record-breaking sluggers like Mark McGwire. The supplement is banned by the World Anti-Doping Agency, and hence from the Olympic Games.

On March 12, 2004, the Anabolic Steroid Control Act of 2004 was introduced into the United States Senate. It amended the Controlled Substance Act to place both anabolic steroids and prohormones on a list of controlled substances, making possession of the banned substances a federal crime. The law took effect on January 20, 2005. Surprisingly, andro was legally defined as an anabolic steroid, even though there is scant evidence that androstenedione itself is anabolic in nature.

On April 11, 2004, the United States Food and Drug Administration banned the sale of Andro, citing that the drug poses significant health risks commonly associated with steroids.

Androstenedione is currently banned by the US military.^[3]

Biological Effects

Androstenedione has been shown to increase serum testosterone levels over an eight-hour period in men when taken as a single oral dose of 300mg per day, but a 100mg dose had no significant effect on serum testosterone. However, serum levels of estradiol increased following both the 100mg and 300mg doses. The study also reported that the serum level of estrogens and testosterone produced varied widely between individuals.^[4] A 2006 review paper summarized several studies which examined the effect of androstenedione on strength training. At dosages of 50mg or 100mg per day, andro had no effect on muscle strength or size, or on body fat levels. One study utilized a daily dosage of 300mg of androstenedione combined with several other supplements, and also found no increase in strength when compared to a control group that did not take the supplements. The review authors speculate that sufficiently high doses may indeed lead to increased muscle size and strength. However, due to the federal ban on androstenedione supplements, it is difficult to carry out new research on its positive and negative effects. The review authors conclude that individuals should not use androstenedione supplements due to the lack of evidence of beneficial effects, the wide variation in individual responses to the supplement, and the risk of unknown side effects.^[5]

Because androstenedione is converted in part to estrogens, people taking this supplement may have estrogenic side-effects, although none of the studies cited above used a sufficiently high dosage to draw any conclusions.

Additional images

Conversion of Androstendione to Estrone	Dehydroepiandrosterone	17-Hydroxyprogesterone	Testosterone
Estrone

References

1. ^ Medical Physiology, Boron & Boulpaep, ISBN 1-4160-2328-3, Elsevier Saunders 2005. Updated edition. Page 1155
2. ^ http://vault.sportsillustrated.cnn.com/vault/article/magazine/MAG1104278/2/index.htm
3. ^ USAF Medical Service Home Page
4. ^ Leder, B., Longcope, C., Catlin, D., Ahrens, B. Shoenfeld, D., and Finkelstein, J.: "Oral Androstenedione Administration and Serum Testosterone Concentrations in Young Men", JAMA, 283(6):779-782
5. ^ Brown, G., Vukovich, M., and King, D.:"Testosterone Prohormone Supplements", Medicine and Science in Sports and Exercise, 38(8):1451-1461.

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