yk11

YK11 was first studied by Japanese researcher Yuichiro Kanno in 2011. It was found to be a partial agonist of the androgen receptor (AR), genetically selective, leading researchers to believe the compound was a SARM. YK11 is an experimental drug candidate and an unapproved substance for use in humans.

YK-11 is a synthetic steroidal selective androgen receptor modulator (SARM).It is a gene-selective partial agonist of the androgen receptor (AR) and does not induce the physical interaction between the NTD/AF1 and LBD/AF2 (known as the N/C interaction), which is required for full transactivation of the AR.

Better Bones: YK11 works by binding to androgen receptors in the body, which are found in various tissues, including bones. Once attached, it activates genes that promote bone growth and mineralization. It means that YK11 could help individuals with osteoporosis or those looking to improve their bone density. Yk11 may increase bone density and mineralization, leading to stronger and healthier bones. It elevates mobility and reduces the risk of fractures.Inhibits Protein Myostatin: Yk11 plays a role in reducing the levels of a protein called myostatin, which is responsible for limiting muscle growth in the body. Yk11 stimulates the production of follistatin, which inhibits myostatin production. Myostatin acts as a regulator, preventing muscles from growing beyond a certain point.

YK-11 is an androgen receptor partial agonist that activates androgen receptor transcriptional activity in HEK293 cells overexpressing androgen receptors when used at a concentration of 0.1 μM.1 It induces expression of the androgen receptor target genes FKBP51 and FGF18 in HEK293 cells when used at a concentration of 10 μM. YK-11 accelerates nuclear translocation of androgen receptors without inducing interaction between the androgen receptor N- and C-termini. In C2C12 cells, YK-11 (500 nM) increases expression of the myogenic regulatory factors MyoD, Myf5, and myogenin, as well as follistatin (Fst), and induces myogenic differentiation.

[1] Yuichiro Kanno, et al. Exp Cell Res. Differential DNA-binding and cofactor recruitment are possible determinants of the synthetic steroid YK11-dependent gene expression by androgen receptor in breast cancer MDA-MB 453 cells DOI:10.1016/j.yexcr.2022.113333
[2] Su Jin Lee, et al. Biochem Biophys Res Commun. Myostatin inhibitor YK11 as a preventative health supplement for bacterial sepsis DOI:10.1016/j.bbrc.2021.01.030
[3] Tomofumi Yatsu, et al. Biol Pharm Bull. Selective Androgen Receptor Modulator, YK11, Up-Regulates Osteoblastic Proliferation and Differentiation in MC3T3-E1 Cells DOI:10.1248/bpb.b17-00748
[4] Mario Thevis, et al. Mol Cell Endocrinol. Detection of SARMs in doping control analysis DOI:10.1016/j.mce.2017.01.040
[5] Yuichiro Kanno, et al. Biol Pharm Bull. Selective androgen receptor modulator, YK11, regulates myogenic differentiation of C2C12 myoblasts by follistatin expression DOI:10.1248/BPB.B13-00231