YK-11 Powder | 1 Gram

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YK-11 Powder — 1 Gram

YK-11 is a synthetic steroidal compound, derived from 5α-dihydrotestosterone (DHT), that has been characterized in cell studies as a partial agonist of the androgen receptor. Although it is commonly grouped with SARMs, its steroid backbone distinguishes it structurally from non-steroidal SARMs such as ostarine or ligandrol. This listing is a research-grade reference compound supplied in powder form for in vitro and laboratory investigation. Identity and purity are third-party verified and documented by a batch-dated, downloadable Certificate of Analysis.

• 98.76% purity (HPLC)
• Third-party verified
• 1,050 mg net
• Batch-dated COA
• UV-resistant foil pouch

Research Context

YK-11 was first described in 2011 by Japanese researchers as a partial agonist of the androgen receptor with gene-selective activity in MDA-MB-453 cells.^[1] Subsequent cell studies reported that it induced follistatin expression during myogenic differentiation of C2C12 myoblasts^[2] and influenced proliferation and differentiation markers in MC3T3-E1 osteoblastic cells.^[3] It has also been examined in a mouse model of bacterial sepsis.^[4] A 2024 rat study reported that YK-11 reached the hippocampus and was associated with increased pro-inflammatory cytokines, activation of apoptotic signaling, and altered memory consolidation.^[5] Most published data on YK-11 come from cell culture, and its effects and safety in humans have not been established.

This material is supplied strictly as a reference compound to support such laboratory investigation. It is not a therapeutic product, dietary supplement, or sports supplement, and no clinical or performance outcomes are claimed or implied for any individual.

Scientific References

1. Kanno Y, Hikosaka R, Zhang SY, et al. (17α,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester (YK11) is a partial agonist of the androgen receptor. Biol Pharm Bull. 2011;34(3):318–323.
2. Kanno Y, Ota R, Someya K, et al. Selective androgen receptor modulator, YK11, regulates myogenic differentiation of C2C12 myoblasts by follistatin expression. Biol Pharm Bull. 2013;36(9):1460–1465.
3. Yatsu T, Kusakabe T, Kato K, et al. Selective androgen receptor modulator, YK11, up-regulates osteoblastic proliferation and differentiation in MC3T3-E1 cells. Biol Pharm Bull. 2018;41(3):394–398.
4. Lee SJ, Gharbi A, Shin JE, et al. Myostatin inhibitor YK11 as a preventative health supplement for bacterial sepsis. Biochem Biophys Res Commun. 2021;543:1–7.
5. From gains to gaps? How selective androgen receptor modulator (SARM) YK11 impact hippocampal function: in silico, in vivo, and ex vivo perspectives. Chem Biol Interact. 2024;394:110971.
6. Van Wagoner RM, Eichner A, Bhasin S, Deuster PA, Eichner D. Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet. JAMA. 2017;318(20):2004–2010.
7. World Anti-Doping Agency. The Prohibited List, Section S1.2: Other Anabolic Agents. WADA.org.