Talk:Androgen

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Active life stage?[edit]

what is the active life stage of androgen

Sorry, I have no idea what you are asking. Try rephrasing and I will try answering. alteripse 00:45, 16 May 2005 (UTC)

What about the effects of androgen on females?[edit]

And in addition to the effect of androgens (their role and issues associated with too much/too little?) in females - how about how they are produced? This article only discusses androgens in the male - half of the species has been omitted, and the information contained in the article is categorically incorrect if applied to females - could someone with the appropriate level of knowledge please correct this major shortcoming? Thanks in advance!

um i still dont understand what it is???[edit]

what are the long term effects of using androgen?[edit]

Like taking one cicle of a month? thanks for any info you can give me.

Sorry, an accurate answer will be vague. The long term effects can be enormously different depending on the dose, your age and sex and current androgen effects. For example the effects measurable 5 years after a healthy 20 year old man takes 1 month of a standard adult male replacement dose will be minimal. Effects of that same dose for 3 months in a prepubertal 12 year old might include permanent loss of 2 inches of adult height potential. Effects of that same dose in a 70 year old man with unknown prostate cancer might include growth of the cancer. Wanted and unwanted short and long term effects of all hormones are always dependent on dose, length of treatment, and the hormone status of the person taking them. No exceptions. alteripse 22:14, 26 September 2005 (UTC)

From androstane / from cholesterol[edit]

The first paragraph says that all androgens are synthesised from androstane. The section on dehydroepiandrosterone says that this one is synthesized from cholesterol in the adrenal cortex. As cholesterol is the original precursor of all steroid hormones, I suppose this latter information can be lifted out. It is confusing rather than informative. / Habj 19:42, 7 November 2005 (UTC)

I agree these are confusing. I removed the following sentences because they are not true in humans. If they are true in certain animals, we need to specify which and be clearer. It is possible that the androstane claim really means that it is a commonly used precursor for laboratory synthesis, or that it is the fundamental androgen structure, even though it is not an important step in human androgen synthesis, or that it is an important androgen precursor in some species of animal.

All natural androgens are steroid derivatives of androstane (19-carbon tetracyclic hydrocarbon nucleus, C19H32).

* Androstenolone: an androgenic steroid secreted by the adrenal cortex and testes, which is a major precursor of testosterone, but is even weaker than androsterone.

Can the contributor who inserted them provide a source? alteripse 03:13, 8 November 2005 (UTC)

Anemia[edit]

Request:

Informative article; please consider including a paragraph on androgen as a treatment for severe anemia. Particularly interested in how it increases hemoglobin. Thanks!

Skypaintur (talk) 22:35, 8 October 2009 (UTC)

Confusing[edit]

This article was written for a medical journal. The medical terms are too technical for common, well-educated laymen to understand. Please edit the material to communicate better with a broader audience. —Preceding unsigned comment added by Vancraft (talkcontribs) 23:55, 21 May 2010 (UTC)

Testosterone=Aggression Disputed in other studies...[edit]

Proposing adding an "Although this is disputed" to the idea that increased testosterone directly causes increased aggression considering there are numerous studies showing the contrary.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8969015&dopt=Abstract

http://odin.dep.no/jd/norsk/dok/andre_dok/rapporter/012041-220005/hov008-bn.html

Screening Methods for Androgens[edit]

The whole section does not belong in this article. I assume someone copy/pasted from their own lab course work, but just in case it was written de novo for this article, the contributor can retrieve it and use it elsewhere. Please do not replace it here thanks. If you really dont understand why it doesnt belong in this project, ask and I will explain. Thanks. alteripse 14:25, 4 June 2006 (UTC)

Extended content
  • The whole animal (in vivo),
  • A combination of the whole animal and isolated organ(s) (ex vivo),
  • Isolated and cultured whole or sections/minced organs, i.e., testis (in vitro),
  • Isolated and cultured cells from the testis (in vitro), and
  • Cell lines (in vitro).

Whole Animal Methods (In Vivo) Intact animals used to measure androgenic activity (Allen and Doisy, 1924; Hershberger et al., 1953). In vivo methods - Take advantage of animal’s innate hormone-directed tissue development and maintenance responses and - Use these responses to identify whether administered substances alter the normal response. Animal’s inherent capacity to produce these hormones must be removed.

  1. Castration.
  2. Immature or juvenile animals used

(M. Chaturvedia, P.C. Mali, A.S. Ansarib; Pharmacology: 2003; 68:38-48)

For androgenicity evaluation of test subs. rats were divided into four groups:
Group I- animals were castrated 30 days before the experiment to serve as controls
Group II, III and IV subjected to castration 30 days before the experiments, followed by administration of test subs., testosterone
propionate (0.01 mg/rat/alternate day s.c.), and test subs. with testosterone propionate, respectively, for 30 days.
Studied--       cauda epididymis sperm motility and density,
        Number of pups,
        Fertility, 
                The weights of testes, epididymis, seminal vesicle, and prostate 

Histoarchitecture of the testes[edit]

Endocrine challenge test (ECT). (Anderson et al., 1992).

Bioassay - to evaluate gonadal response to a substance by measuring the steroid hormone production and release following administration of test subs. The intact mature animal is challenged with GnRH or an LH- or FSH-like substance that stimulates a hormonal response. Serial blood samples collected and measured to evaluate whether the substance being tested causes increased testosterone Techniques used include tail vein sampling, tail vein treatments and/or jugular catheterization (Fail et al., 1995; Fail and Anderson, 2002). A number of different endpoints have been used.

  • Plasma testosterone, before (basal) and after stimulation. Testosterone concentrations measured by RIA (Fail et al., 1995; 1996).
  • Epididymis weight, caudal sperm count, testicular sperm heads, and sperm motility (Fail et al., 1995; 1996).

Combination of Whole Animal and Isolated Organs Method (ex vivo)[edit]

  • First involves treating immature or adult animals according to selected dosing regimen.
  • Route, duration of exposure are not constrained.
  • In addition to the acute exposures, exposures for ex vivo studies can actually begin as early as gestation and continue for as long as the life expectancy of animal being tested.
  • During the in-life exposure period, blood samples can be collected at specified times for serum hormone analysis.
  • After the exposure period is completed, animal is killed, at which time final necropsy

specimens collected, and the testis isolated.

  • The gonads are then processed according to the type of in vitro preparation that was selected to assess the test substance’s effect.

Isolated Organ Methods (in vitro)[edit]

  • The organs where steroidogenesis occurs removed from animal & kept viable, thereby providing an isolated organ method for assessing substances as stimulants of the steroidogenic pathway.
  • Organs, once isolated, can be used whole or further processed into sections or minced organ preparations
  • These preparations allow effect of given test substance to be measured without influence of other organs or systems/other physiological factors.
  • The integrity and interrelationship of the cells and tissues within the organ remain intact.
  • These preparations retain the cellular and biochemical pathways that involve the receptor and second messenger.
  1. way in which the organ is processed.
  • Whole organ -- after the organ is removed and placed in media, no further processing occurs
  • Sectioned organ -- For the testes, an organ section refers to an organ that has been cut such that each section constitutes 1/8 to ½ the size of the whole organ, i.e., 50 to 250 mg (rat testis). *Minced organ -- organ that has been cut into very small sizes, i.e., 1 to 50 mg (rat testis).

The perfused testis[edit]

  1. Provides a method to simulate biosynthesis and secretion of testicular steroid hormones

Developed for the rabbit by Vandemark and Ewing (1963), modified for the rat by Chubb and Ewing (1979).

  1. Apparatus is sterilized and then assembled.
  2. The system must be air-free to prevent bubbles from entering the perfusate and blocking flow.
  3. Testis is removed, spermatic artery cannulated, organ flushed of blood with perfusate solution.
  4. The testis is placed in the organ chamber and perfusion initiated.
  5. Test substance given after a preliminary perfusion for approximately 1 hour, the temperature (370 C), rate of flow (20 mL/hr), and pH (7.4) are monitored and maintained.
  6. The perfusion can be maintained for 6 to 10 hours.
  7. Samples are collected from the perfusate for analysis.

Simple Whole Organ Incubation technique[edit]

  • Involves removal of the testis and incubation of the organ in medium for testing.
  • For the whole testis (Deb et al., 1980), animal anesthetized or euthanized & testes removed.
  • The testes are incubated in Kreb-Ringer-bicarbonate solution (pH 7.6) at 370 C & atmosphere of 95 percent O2 and 5 percent CO2
  • Testes are incubated with or without the substance being tested, as well as with or without stimulant, e.g., LH.

Screening for AR activity using Gene expression assays[edit]

  • Assay involves transient transfection of a tester cell line with a plasmid base receptor and the reporter, followed by chemical exposure and measurement of the modulation of gene expression.

· KB2 assay (Vickie S. Wilson; 2002: Toxicological Sciences 66, 69-81) · Describe the effects of androgens in a stably transformed cell line that they developed (MDA-KB2), which expresses the human AR (hAR) and an AR-responsive promoter linked to a luciferase reporter gene (MMTV-luc). · Main advantage of KB2 assay -- it employs a genetically modified cell line, which eliminates the effort and inherent variability associated with repeated transient transfections. · The breast cancer cell line, MDA-MB-453, was stably transformed with the MMTV.luciferase.neo reporter gene construct. · Since both GR and AR are present in the MDA-MB-453 cells, and both receptors can act through the MMTV promoter, compounds that act through either AR or GR activate the MMTV luciferase reporter. · AR agonists such as dihydrotestosterone (DHT), and GR agonists such as dexamethasone (DEX), corticosterone, and aldosterone induce luciferase expression at appropriate concentrations. · DHT consistently produced 3–9-fold induction at concentrations from 0.1 to 10 nM. · To distinguish AR- from GR-mediated ligands, chemicals were assayed concurrently with the antiandrogen, hydroxyflutamide (OHF), which blocks AR- but not GR-mediated responses. · These cells are relatively easy to culture and maintain. · Responsiveness was monitored over time and was stable for more than 80 passages. · Some advantages -- relatively rapid (2 days), eliminates the need for transfection, can be conducted in a 96-well plate format, produces consistent reproducible results

  • Construction and verification of reporter plasmid containing MMTV. neo.luc-- The neomycin gene was removed from pcDneo and inserted into pMMTV.luc
  • Transformation, isolation, and screening of stable clones.

MDA-MB-453 cells (ATCC No. HTB 131) used for transformation. Cells were seeded at 2 x 105 cells per 60-mm culture dish in maintenance medium, then transformed using Fugene 6 (Roche) per manufacturer's protocol, with 5 µg pMMTV.luc.neo per dish. To screen clones for responsiveness to an androgen agonist, cells grown from individual colonies were plated at 1 x 104 cells per well in 96-well luminometer plates, allowed to attach. When cells were attached, the medium was replaced with freshly prepared dosing medium containing ethanol only (negative control), an agonist (dihydrotestosterone, DHT; 1 nM), or the agonist plus a known competitor (hydroxyflutamide, OHF; 1 M). Cells were dosed with 100 µl of medium/well and incubated for 20–24 h, --harvested with 25 µl/well of lysis buffer and assayed for luciferase reporter activity.

Relative light units per well determined using a 96-well MLX Luminometer.
Clones with a minimum 2-fold response to 1 nM DHT were retained in culture.
The final clone (MDA-kb2) was chosen based on appropriate ligand responsiveness and genetic stability over time.
  • Maintenance of cultures and transcriptional activation assays.
-MDA-kb2 cells stably transformed with the pMMTV.neo.luc reporter gene construct were maintained in L-15 media supplemented with, 100
U/ml penicillin, 100 µg/ml streptomycin, and 0.25 µg/ml amphotericin B at 37°C, without CO2.
-For experiments, cells were plated at 1 x 104 cells per well in 100 µl of medium in 96-well luminometer plates.

-When cells were attached (4–6 h), medium was removed and replaced with dosing medium. Stock solutions for each chemical were prepared at 1000x in ethanol. - Dosing medium was prepared at the time of treatment by aliquoting 1 µl of stock solution into 1 ml of maintenance medium -Vehicle control wells contained 100 µl medium/ well with1 µl of ethanol/ml of medium. Each plate also contained either 0.1 or 1.0 nM DHT, or DHT/plus 1 µM OHF as agonist control. -Cells were incubated overnight at 37°C without CO2.

Luciferase activity was assayed --using an MLX microtiter plate luminometer and quantified as relative light units (RLU).

-Relative light units were converted to fold induction above the vehicle control value for each replicate for statistical analysis. -Stability of Androgenic Response and Baseline Activity Androgen-induced luciferase activity measured over approximately 9 months of continuous culture to assess the stability and responsiveness of the MDA-kb2 clone.

-cells were assayed over more than 80 passages for their response to 1 nM DHT.

-At early passages, luciferase induction relative to solvent controls was about 10 fold.

-In continuous culture, luciferase induction dropped over time, but responsiveness stabilized at 30 to 40 passages.

-In later passages, a minimum of 5–6-fold induction in response to 1 nM DHT was consistently maintained over the remaining test period for more than 80 passages, demonstrating stable expression of the luciferase gene. P. C. Hartig,1, Toxicological Sciences 66, 82-90 (2002)

  • Attempt to deliver the genes via replication-defective adenovirus transduction
  • describe the responses of several androgens in two AR-responsive in vitro assays. These assays used transduced MDA-453 and CV-1 cells, cell lines.
  • Ad/mLuc7 virus used, which contains the luciferase gene regulated by the glucocorticoid-inducible hormone response element found in the mouse mammary tumor virus (MTV) LTR
  • Transduction assays were performed in 96-well plates.

· Twenty-four h prior to transduction, 5 x 104 cells were plated per well. · Medium was removed and replaced with 20 µl of control medium or medium with diluted virus. · MDA cells (which contain endogenous AR) were transduced with Ad/mLuc7 reporter virus at a multiplicity of infection (MOI) of 50 (i.e., 50 virions per cell). · CV-1 cells (which lack native AR) were transduced with Ad/mLuc7 at a MOI of 50 and Ad5hAR at a MOI of one. · Dishes were rocked every 15 min for 1 h, incubated 3 additional h, · 200 µl medium/medium + test chemicals added to each well · followed by a 48-h incubation. · Plates were either frozen at –80°C, or assayed immediately for luciferase activity. · Luciferase activity was quantitated in an MLX microtiter plate luminometer, data expressed in relative light units (RLU). · For androgen agonists, which stimulate luciferase expression, treatments compared to the media/ethanol control group · Relative light units were converted to fold induction above the media value for each replicate

(L. G. Parks; Toxicological Sciences 62, 257-267 (2001)

COS whole cell human androgen receptor (hAR) binding assay[edit]

  • In 3 blocks, COS cells (SV-40 transformed monkey kidney line ATCC # CRL-1650) were transiently transfected with hAR expression vector pCMVhAR
  • COS cells were plated at 200,000 cells/well in 12 plates and transfected with 1 µg of pCMVhAR
  • After a 3-h transfection period, cells were washed and incubated overnight
  • Twenty-four hours later, medium replaced with 200 µl of serum-free/phenol red-free DMEM with R1881 plus 200 microliters of medium containing tast substance (400-µl incubation volume, with a concentration factor of 40x).
  • Cells were incubated for 2 h with 5 nM [3H] R1881 at 37°C under an atmosphere of 5% CO2.
  • Cells were washed in phosphate-buffered saline and lysed in 200 µl ZAP

(0.13 M ethylhexadecyldimethylammonium bromide with 3% glacial acetic acid).

  • The lysate was added to 5 ml OPTI-fluor scintillation cocktail and radioactivity was counted using a Beckman LS 5000 TD counter

· 1 µM hydroxyflutamide was added to half of the samples to see if this potent antiandrogen would block the test substance-induced luciferase activity. · Cells also were exposed to 1 nM DHT as a positive control.

CV-1 AR and GR 40-dependent transcriptional activation assays

  • Experiments, each with several replicates, were conducted to determine induced AR- or GR-dependent gene expression in CV-1 cells (monkey kidney line, ATCC # CCL-70).
  • 200,000 CV-1 cells were plated in a 60-mm dish and then transiently cotransfected with 1 µg pCMVhAR and 5 µg MMTV-luciferase reporter using 5 µl Fugene reagent in 95 µl serum-free medium as per the manufacturer's protocol.

· Twenty-four h after transfection, medium was aspirated and replaced with 2 ml of medium containing test substance. · Cells then incubated at 37°C under 5% carbon dioxide. · After 5 h of exposure, medium was removed, and cells were washed once with phosphate-buffered saline and harvested with 500 µl lysis buffer. · Relative light units of 0.05-ml aliquots of lysate determined using a Monolight 2010 luminometer.

COS cell immunocytochemistry Experiment conducted to visualize, by immunofluorescence, the ligand-induced nuclear translocation of hAR in COS cells.

·Two chamber slides were seeded with 100,000 cells/chamber in 2 ml DMEM supplemented with 10% FBS ·Cells transfected with 0.5 µg pCMVhAR ·Following transfection, 2 ml medium containing test substance, added to slides, incubated for 24 h at 37°C under 5% CO2. ·The next day, medium removed, cells washed once with DPBS (Dulbecco's phosphate buffered saline), allowed to dry for 45 min at room temperature, fixed for 10 min with 95% ethanol (-20°C), blocked with 5% BSA, and incubated overnight with primary AR antibody (1:1000) at 4°C. ·The following day, cells were washed once with DPBS and incubated with fluorescently labeled secondary antibody for 30 min at room temperature. ·To visualize the nuclei, cells were counter-stained with DAPI, a DNA stain, mounted with fluoromount slides examined using Microscope at 200 x magnification. ·The localization of the AR was classified as either perinuclear or nuclear in a blinded fashion from 10 randomly selected fields from a slide for each site. ·In another experiment, cells were exposed to 1 nM DHT, as a positive control.

Novel yeast bioassay system for detection of androgenic compounds. Lee HJ, Lee YS, Kwon HB, Lee K.;Toxicol In Vitro. :2003 Apr;17(2):237-44.

Report the development of a rapid, simple, effective yeast detection system for androgenic compounds, based on the yeast two-hybrid protein interaction.

  • A yeast strain, ARhLBD-ASC1, was established by co-transformation of yeast cells harboring a lacZ reporter plasmid with two vectors expressing each of LexA fused hinge-ligand binding domain (hLBD) of androgen receptor (AR) and B42 fused ASC-1 that interacts with
AR-hLBD in an androgen-dependent manner.
  • In this strain, androgens, but not other hormones, strongly stimulated the beta-galactosidase activity in a dose-dependent manner.

Which are stress hormones? Estrogens? Anabolic steroids? Androgens? All?[edit]

"Androgens are also the original anabolic steroids and the precursor of all estrogens, which are stress hormones." — Preceding unsigned comment added by Xojo (talkcontribs) 18:25, 3 January 2013 (UTC)

"Androgens are also the original anabolic steroids and the precursor of all estrogens, which are stress hormones." To my nonbiochemical eye and ear, the last phrase refers to its nearest antecedent, estrogens. Is that correct? Should the sentence be recast? Xojo (talk) 18:31, 3 January 2013 (UTC)

Neither androgens nor estrogens are "stress" hormones. The glucocorticoids are "stress" hormones. I have therefore deleted stress hormone from the lead. Boghog (talk) 03:45, 12 August 2013 (UTC)

Why does "androstadiene" redirect here?[edit]

Word is not used in article. 86.139.166.113 (talk) 00:54, 12 August 2013 (UTC)

Androstadienes at the US National Library of Medicine Medical Subject Headings (MeSH) – "Derivatives of the steroid androstane having two double bonds at any site in any of the rings." I suppose the androstadiene redirect should be converted into a stub similar to androstane. Boghog (talk) 04:08, 12 August 2013 (UTC)

Androgenic impact of exercise[edit]

Nothing can be understood from the entire section of 'Androgenic impact of exercise'. Every sentence contradicts the one the came before it. All the information there should be organized so it would be clear when the androgens go up and when they go down.

The problem with this section is that it is based almost entirely on primary sources. The results of these studies are often contradictory. Even worse, this section mixes animal with human studies. Since results in animals don't always translate to humans, this can cause additional confusion. This entire section needs to be rewritten based on WP:MEDRS compliant secondary sources (i.e., review articles). This would likely result in a much more coherent picture. Boghog (talk) 14:29, 1 February 2015 (UTC)
I also came here to comment this section seems disproportionately long and detailed, considering the article is about a class of chemical/hormone while the section is narrowly focused on what exercise does to values of different hormone levels - some of which aren't even androgens as far as I can tell. As said above it should generally be shorter, clearer, and use secondary sources, but maybe the information should also be moved away from here and to some exercise-related article similar to Neurobiological effects of physical exercise. Cyrej (talk) 19:33, 16 September 2015 (UTC)