Membrane androgen receptor

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Membrane androgen receptors (mARs) are a group of G protein-coupled receptors (GPCRs), which bind and are activated by testosterone and/or other androgens. [1] [2] [3] Unlike the androgen receptor (AR), a nuclear receptor which mediates its effects via genomic mechanisms, mARs are cell surface receptors which rapidly alter cell signaling via modulation of intracellular signaling cascades. [2] [3] Known or proposed mARs include ZIP9 and GPRC6A. [2] [4]

GPRC6A has been found to be involved in testicular function and prostate cancer. [2] [3] mARs have also been found to be expressed in breast cancer cells. [5] Activation of mARs by testosterone has been found to increase skeletal muscle strength, indicating potential anabolic effects. [6] mARs have also been implicated in the antigonadotropic effects of androgens. [7] 3α-Androstanediol, an active metabolite of dihydrotestosterone (DHT) and a weak androgen as well as a neurosteroid via acting as a positive allosteric modulator of the GABAA receptor, rapidly influences sexual receptivity and behavior in animals, an effect that is GABAA receptor-dependent. [7]

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<span class="mw-page-title-main">Membrane estrogen receptor</span>

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<span class="mw-page-title-main">Zinc transporter ZIP9</span> Protein found in humans

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<span class="mw-page-title-main">Pharmacology of bicalutamide</span>

The pharmacology of bicalutamide is the study of the pharmacodynamic and pharmacokinetic properties of the nonsteroidal antiandrogen (NSAA) bicalutamide. In terms of pharmacodynamics, bicalutamide acts as a selective antagonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT). It has no capacity to activate the AR. It does not decrease androgen levels and has no other important hormonal activity. The medication has progonadotropic effects due to its AR antagonist activity and can increase androgen, estrogen, and neurosteroid production and levels. This results in a variety of differences of bicalutamide monotherapy compared to surgical and medical castration, such as indirect estrogenic effects and associated benefits like preservation of sexual function and drawbacks like gynecomastia. Bicalutamide can paradoxically stimulate late-stage prostate cancer due to accumulated mutations in the cancer. When used as a monotherapy, bicalutamide can induce breast development in males due to its estrogenic effects. Unlike other kinds of antiandrogens, it may have less adverse effect on the testes and fertility.

References

  1. Bennett NC, Gardiner RA, Hooper JD, Johnson DW, Gobe GC (2010). "Molecular cell biology of androgen receptor signalling". Int. J. Biochem. Cell Biol. 42 (6): 813–27. doi:10.1016/j.biocel.2009.11.013. PMID   19931639.
  2. 1 2 3 4 Wang C, Liu Y, Cao JM (2014). "G protein-coupled receptors: extranuclear mediators for the non-genomic actions of steroids". Int J Mol Sci. 15 (9): 15412–25. doi: 10.3390/ijms150915412 . PMC   4200746 . PMID   25257522.
  3. 1 2 3 Lang F, Alevizopoulos K, Stournaras C (2013). "Targeting membrane androgen receptors in tumors". Expert Opin. Ther. Targets. 17 (8): 951–63. doi:10.1517/14728222.2013.806491. PMID   23746222. S2CID   23918273.
  4. Pi M, Quarles LD (June 2011). "GPRC6A regulates prostate cancer progression". Prostate. 72 (4): 399–409. doi:10.1002/pros.21442. PMC   3183291 . PMID   21681779.
  5. Papadopoulou N, Papakonstanti EA, Kallergi G, Alevizopoulos K, Stournaras C (2009). "Membrane androgen receptor activation in prostate and breast tumor cells: molecular signaling and clinical impact". IUBMB Life. 61 (1): 56–61. doi: 10.1002/iub.150 . PMID   19109827.
  6. Dent JR, Fletcher DK, McGuigan MR (2012). "Evidence for a Non-Genomic Action of Testosterone in Skeletal Muscle Which may Improve Athletic Performance: Implications for the Female Athlete". J Sports Sci Med. 11 (3): 363–70. PMC   3737931 . PMID   24149341.
  7. 1 2 Foradori CD, Weiser MJ, Handa RJ (2008). "Non-genomic actions of androgens". Front Neuroendocrinol. 29 (2): 169–81. doi:10.1016/j.yfrne.2007.10.005. PMC   2386261 . PMID   18093638.