SARMs S4/Andarine Catalog Description - 25mg/ml, 60ML
SARM S-4, also called Andarine, is a selective androgen receptor modulator research chemical under development and testing by GTx Inc for benign prostatic hypertrophy (BPH), muscular dystrophy and muscle wasting conditions, and osteoporosis. Andarine has partial agonist activity in certain tissues, with full agonist activity for the androgen receptor (AR) in other tissues, notably skeletal muscle. Similar to an androgenic-anabolic steroid (AAS) without the same structure or side-effects, andarine (S4) has also been demonstrated to prevent bone loss, reduce adiposity (body-fat percentage), and improve muscular strength and muscle mass in orchidectomized and ovariectomized rats. Andarine is milder than other SARMs in terms of androgenic and anabolic effects.
Andarine reduced prostate weight as effectively as finasteride and without creating any loss of muscle mass or the other side effects common with androgen receptor binding antagonist compounds. According to Gao et al (2006), S-4 prevents DHT from binding and activating, but bypasses the typical side-effects of anti-androgens on other (non-prostate) androgen receptors due to the fact that S-4 itself is a full agonist of androgen receptors in those tissues. With a different level of affinity (the ease with which a ligand can bind to a receptor and displace other agonists) and efficacy (or intensity, the level of effect at a given amount of binding) than other androgen receptor agonists, such as DHT, andarine has the quality of being able to reduce benign prostatic hypertrophy without the same risk profile of DHT . While andarine acts as a full agonist in many tissues (such as skeletal muscle and the pituitary), it behaves as a partial agonist in the prostate, a trait that further enhances safety.
SARMs offer several theoretical advantages as a therapeutical alternative over traditional compounds such as testosterone or related androgenic-anabolic steroids (AAS). SARMs are orally active, non-hormonal small molecule compounds meaning that unlike most AAS, they do not present issues of requiring injection or concerns over toxicity to organs such as the liver. As such, in studies SARMs can be self-administered and given to populations that would not normally be appropriate for anabolic-androgenic steroids despite potential therapeutic benefit. SARMs do not convert enzymatically to hormones, and have more specific effects than the vast majority of AAS. The selectivity for the androgen receptor means a theoretically improved safety and efficacy profile compared to other compounds with the same class of therapeutic uses.
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 Kearbey JD, Gao W, Narayanan R, Fisher SJ, Wu D, Miller DD, Dalton JT. Selective Androgen Receptor Modulator (SARM) treatment prevents bone loss and reduces body fat in ovariectomized rats. Pharm Res. 2007 Feb;24(2):328-35.
 Gao W, Reiser PJ, Coss CC, Phelps MA, Kearbey JD, Miller DD, Dalton JT. Selective androgen receptor modulator treatment improves muscle strength and body composition and prevents bone loss in orchidectomized rats. Endocrinology. 2005 Nov;146(11):4887-97.
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 Mohler ML, Bohl CE, Jones A, Coss CC, Narayanan R, He Y, Hwang DJ, Dalton JT, Miller DD. Nonsteroidal selective androgen receptor modulators (SARMs): dissociating the anabolic and androgenic activities of the androgen receptor for therapeutic benefit. Journal of Medicinal Chemistry 52 (12): 3597–617. 2009