YK-11, one of the newest SARMs for sale, acts as a gene-specific agonist of the androgen receptor (AR) in MDA-MB-453 cells. YK-11 is a synthetic steroidal compound that acts as a partial agonist of the androgen receptor in vitro, as demonstrated in C2C12 muscle cell studies. While this AR activity may mimic some effects of endogenous testosterone, there is currently no evidence confirming tissue-selective binding or activity in muscle or bone tissues in vivo.
YK-11 works on multiple anabolic pathways. YK-11 has demonstrated greater anabolic activity in vitro in C2C12 myoblasts compared to DHT. YK-11 promoted a cascade of muscle growth and key myogenic regulatory factors in skeletal muscle tissue, such as myogenic differentiation factor (MyoD) and myogenic factor 5 (Myf5), to a significantly greater extent than DHT.
YK-11 has been shown in cell studies to increase follistatin expression through androgen receptor–dependent signaling, which indirectly inhibits myostatin activity and promotes myogenic differentiation. However, there is no evidence that YK-11 directly inhibits myostatin, and these effects have only been observed in vitro.
This can in part explain why YK-11 exerts its selective modulation of the AR. Unlike testosterone and most other AR-mediated anabolic agents, YK-11 is orally bioavailable, so it does not require injection for proper absorption. At this time, YK-11 is intended strictly for laboratory research use only, and the side effects are not fully known.
YK-11 FAQs
Like other SARMs, lab-tested YK-11 has a dose-dependent reductive effect on natural testosterone levels in males.
Data shows that YK-11 suppresses myostatin via modulation of the follistatin pathway.
Studies suggest that YK-11 induces the expression of osteoblast-specific differentiation markers, such as osteoprotegerin and osteocalcin, which may facilitate bone tissue production.
Why is Sports Technology Labs the best place to buy YK-11 online?
Researchers highly seek after YK-11 due to its activity in both the traditional androgen-mediated growth pathway and the follistatin pathway. It’s not hard to find YK-11 and other SARMs for sale online. Still, Sports Technology Labs is the best place to buy YK-11 online because of our consistent, verifiable, high-quality, fast shipping, safer bottling and packaging, and our outstanding customer service and handling time. Our YK-11 is also available in pure powder form.
At Sports Technology Labs, you can find the highest quality YK-11 for sale anywhere on the internet. When you buy SARMs from Sports Technology Labs, you are choosing the highest quality ingredients. Minimum 98% pure compounds tested and certified by accredited American third-party labs, suspended in USP-grade (the highest grade) PEG-400, bottled in America.
Our products come in glass bottles with fixed glass droppers to prevent the leaching of unwanted plasticizers like BPA, and to avoid contamination when using external measuring tools. We run a transparent business, with no discreet payment methods necessary and no misrepresentation of our products, only the highest quality research chemicals available online, secured by our 60-day money-back guarantee, with free shipping available for orders over $149. For those who require expedited delivery, we also offer express shipping. Customers who subscribe to our email list enjoy a 10% discount and an extra 10% off when paying with cryptocurrency.
That’s why we are confident in our claim that we offer the best YK-11 for sale on the market today. And if you have any questions about our liquid YK-11 products, you can also contact us, and we’ll respond as soon as possible.
Start your research or purchasing journey with Sports Technology Labs today and experience the difference in quality and service.
Additional information
Weight
3.0 oz
YK-11
Each batch is bottled and tested in the USA to ensure accuracy and purity. Our Certificates of Analysis confirm that products meet the listed specifications:
A 2023 rat study found that YK-11 administration induced significant oxidative stress and mitochondrial dysfunction in the hippocampus, a brain region essential for learning and memory. These changes were accompanied by inflammation in hippocampal tissue and impaired memory consolidation, indicating potential neurotoxic effects at high doses. While these findings are limited to preclinical models, they raise concerns about possible neurological risks associated with YK-11, particularly with prolonged or high-dose exposure.
Bone Growth
YK-11, in combination with dihydrotestosterone (DHT), was found to accelerate cell proliferation and mineralization in MC3T3-E1 mouse osteoblast cells. YK-11 treatment also induced the expression of osteoblast-specific differentiation markers, such as osteoprotegerin and osteocalcin, compared to untreated cells. These effects were diminished by treatment with an androgen receptor (AR) antagonist, indicating that the androgen receptor mediates the observed results.
Mechanisms for Bone Recovery
Investigation into the mechanisms of YK-11’s action on the AR revealed that it activates non-genomic signaling via phosphorylation of Akt protein. This signaling pathway is known to be a key regulator of androgen-mediated osteoblast differentiation, making it a promising candidate for future research in the field of bone tissue engineering.
Cellular and Osteogenic Activity
In in vitro studies, YK-11 has been shown to enhance expression of Myf5 and myogenin mRNA in C2C12 myoblasts, indicating a potential role in myogenic differentiation. Additionally, in osteoblastic MC3T3-E1 cells, YK-11 increased alkaline phosphatase (ALP) activity and upregulated osteoprotegerin and osteocalcin mRNA expression in a dose-dependent manner (0.1–1.0 µM). These findings suggest possible osteogenic effects at the cellular level, though they have not been replicated in human or in vivo studies.
Muscle Effects
Muscle Growth
What sets YK-11 apart is that a key component of its anabolic activity is modulated via expression of follistatin. They discovered this by co-administering anti-follistatin antibodies with YK-11 to measure the difference in effects. Follistatin has been shown to promote insulin-stimulated glucose and amino acid uptake into skeletal muscle cells, improving insulin sensitivity directly and increasing skeletal muscle mass. Follistatin proteins also block inhibitory ligands from binding to Transforming Growth Factor-ß.
Follistatin Effects on Muscle Tissue
Perhaps the most alluring effect of follistatin is its ability to bind and neutralize catabolic proteins, including Activin A, Activin B, and Myostatin. Unfortunately, follistatin proteins themselves undergo rapid proteolysis and have limited bioavailability and half-life even when injected directly into a wasting muscle. YK-11, however, stimulates the body to produce more follistatin proteins systemically and locally, which may circumvent this shortfall of direct follistatin administration and promote muscle growth.
Muscle Wasting
Animal studies have investigated the effects of YK-11 as a potential treatment for sepsis-induced muscle wasting. Researchers observed protective effects on muscle tissue and organ tissue, as well as suppression of gram-negative bacteria-induced cytokine inflammation. Mortality rate in eight-week-old septic mice treated with YK-11 also decreased significantly. They concluded that this was due to the suppression of myostatin as well as an increase in the expression of the follistatin gene.
False Claim:
Additionally, YK-11’s effects on muscle growth may contribute to increased muscle strength and endurance in research models.
Supporting Evidence:
Current evidence for this claim is indirect and based on in vitro studies rather than direct functional research. In mouse C2C12 myoblasts, YK-11 acts as a partial androgen receptor agonist, leading to follistatin upregulation, which indirectly inhibits myostatin signaling. This results in enhanced myogenic differentiation and increased expression of muscle differentiation markers at concentrations around 500 nM (Yatsu et al., 2018). Because muscle hypertrophy is often associated with improved strength and endurance, these cellular findings suggest a plausible mechanism by which YK-11 could contribute to functional gains in research settings.
However, it is important to note that no published animal or human studies have directly measured muscle strength or endurance following YK-11 administration. Thus, this claim is theoretical and supported only by mechanistic cellular data, not by in vivo functional outcomes.
Side Effects
Little is revealed in clinical studies regarding YK-11 side effects; however, anecdotal reports online indicate the potential for joint pain, mild male-pattern hair loss, acne, and aggression. Due to its action upon the androgen receptor (AR), it is plausible that YK-11 may result in side effects commonly reported with other anabolics, for example, elevated hemoglobin or hematocrit, high blood pressure, insomnia, nausea, or liver damage. YK-11 is only approved for laboratory research purposes and is not approved for human consumption.
Testosterone
While there are currently no published clinical studies directly measuring testosterone suppression from YK-11, its steroidal structure and partial androgen receptor agonist activity suggest it could suppress the hypothalamic–pituitary–gonadal (HPG) axis, potentially leading to reduced natural testosterone production and hormonal imbalances. This effect has been theorized mechanistically and is frequently reported anecdotally, but formal research is lacking (Source).
Unreliable sources often claim that long-term hypogonadism is a known risk of YK-11 use; however, this has not been clinically proven. There is no peer-reviewed evidence demonstrating that YK-11 causes long-term hypogonadism in humans or animals. That said, due to its steroidal structure and partial androgen receptor activity, it is biologically plausible that YK-11 could suppress the hypothalamic–pituitary–gonadal axis over extended periods, potentially leading to reduced natural testosterone production and increasing the theoretical risk of long-term hypogonadism.
Phosphorylation of Akt protein
Research has shown that YK-11 enhances the phosphorylation of the Akt protein through rapid, androgen receptor–dependent non-genomic signaling; however, this finding is based solely on in vitro studies using mouse C2C12 myoblasts. There are currently no human or in vivo studies confirming whether this Akt phosphorylation occurs in actual muscle tissue following YK-11 administration. The precise upstream mechanism by which YK-11 activates Akt remains unclear, as the original study documented the effect but did not map the whole signaling cascade. Referring to this as “enhanced mechanisms” is overly vague; more accurately, the phenomenon involves rapid, AR-mediated, non-genomic activation of Akt in muscle cells, observed under controlled laboratory conditions (Source).
Cardiovascular Concerns
Although direct human data are lacking, emerging evidence and mechanistic understanding suggest that YK-11 may pose cardiovascular risks, including a theoretical increased risk of heart attack and stroke. This aligns with known effects of androgen receptor–active compounds on lipid profiles, clotting factors, and vascular health. Further research is needed to clarify these risks in humans.
Storage: Store in a cool, dry place away from direct sunlight to maximize shelf life.
30 mL Liquid YK-11 per bottle with 10 mg/mL.
Each bottle contains a quantity of 300 mg YK-11.
Current stock levels are updated regularly to ensure availability.
Includes a graduated 1 mL glass pipette for convenient measurement.
Glass bottle with UV resistance to minimize degradation.
Tamper-proof seal to ensure safety in transit.
Less than 5% variance in concentration, guaranteeing consistency.
Formulated and packaged to prevent evaporation in storage.
To place an order for YK-11, please specify the desired quantity during checkout. YK-11 and related products are available for direct purchase through our website for convenient online ordering.
SKU: 9
This preparation is for laboratory research purposes only and is not approved by the FDA for human consumption. YK-11 IS NOT A DIETARY OR SPORTS SUPPLEMENT.
Abuse Warning
YK-11 is an investigational compound still awaiting FDA approval and is not a dietary supplement. The perception that YK-11 is a safer alternative to anabolic-androgenic steroids (AAS) is false. At Sports Technology Labs, we are chemical suppliers, not medical doctors, and our expertise is sourcing and quality control. YK-11 is a controlled substance in many countries and has been banned by the World Anti-Doping Agency (WADA). Sports Technology Labs does not encourage or condone consumer use of SARMs products; they are for research purposes only.
SARMs should only be used under the supervision and direction of a medical doctor or designated research authority. We strongly discourage the use of SARMs for performance enhancement in sports and bodybuilding, and warn against “bro science” and peer consensus when making decisions about human health.
False Claims
Many vendors emphasize quality assurance and independent lab testing when marketing their YK-11 products, often offering the compound in various forms such as capsules and injectables. However, the actual quality and purity of these products cannot be independently verified unless they are manufactured in a CGMP (Current Good Manufacturing Practice)–certified facility, which should be clearly indicated on the product labeling. Without this certification and verified third-party analytical data, claims regarding product quality, purity, and accuracy remain unsubstantiated, and there is no reliable way to confirm that the contents match what is advertised.
Quality Control and Regulatory Issues
Significant quality control problems have been documented in the unregulated research chemical market for YK-11. A 2024 study found that many products marketed online as YK-11 contained undeclared or unapproved active substances, manufacturing contaminants, or incorrect dosages, posing potential health hazards. Because most YK-11 products are sold under “for research purposes only” labels, vendors avoid stricter regulatory oversight by not placing updated COA’s on their website. At Sports Technology Labs, we emphasize transparency in every batch. A full list of COA’s can be found on every product page.
Legal Status and International Actions
The unregulated nature of YK-11 means that product labels may not match actual contents, and legal risks vary by jurisdiction. In countries like Canada, authorities have seized YK-11 products marketed as dietary supplements, reflecting growing enforcement actions against mislabeled compounds. In most jurisdictions, YK-11 is not approved for human use, and possession or sale may fall into legal gray areas depending on labeling and intent. Trust vetted sources like Sports Technology Labs to deliver high-quality compounds for your research lab.
Scientific References:
1. Kanno Y, Hikosaka R, Zhang SY, Inoue Y, Nakahama T, Kato K, Yamaguchi A, Tominaga N, Kohra S, Arizono K, Inouye Y (2011). “(17α,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester (YK-11) is a partial agonist of the androgen receptor”. Biological & Pharmaceutical Bulletin. 34 (3): 318–23. PMID 21372378
2. Kanno Y, Ota R, Someya K, Kusakabe T, Kato K, Inouye Y (2013). “Selective androgen receptor modulator, YK-11, regulates myogenic differentiation of C2C12 myoblasts by follistatin expression”. Biological & Pharmaceutical Bulletin. 36 (9): 1460–5. PMID 23995658.
3. Han X, Moller LLV, et al. Mechanisms involved in follistatin-induced hypertrophy and increased insulin action in skeletal muscle. J Cachexia Sarcopenia Muscle. 2019 Aug 11. doi: 10.1002/jcsm.12474
4. Castonguay R, Lachey J, Wallner S, et al. Follistatin-288-Fc Fusion Protein Promotes Localized Growth of Skeletal Muscle. J Pharmacol Exp Ther. 2019 Mar;368(3):435-445. doi: 10.1124/jpet. 118.252304. Epub 2018 Dec 18.
5. Lee SJ, Gharbi A, Shin JE, Jung ID, Park YM. Myostatin inhibitor YK-11 as a preventative health supplement for bacterial sepsis. Biochem Biophys Res Commun. 2021 Mar 5;543:1-7. Doi: 10.1016/j.bbrc.2021.01.030. Epub 2021 Feb 12. PMID: 33588136.
6. Yatsu T, Kusakabe T, Kato K, Inouye Y, Nemoto K, Kanno Y. Selective Androgen Receptor Modulator, YK-11, Up-Regulates Osteoblastic Proliferation and Differentiation in MC3T3-E1 Cells. Biol Pharm Bull. 2018;41(3):394-398. doi: 10.1248/bpb.b17-00748. PMID: 29491216
