YK-11
Steroidal SARM inducing follistatin; myostatin pathway modulator
Mechanism of Action
YK-11 is a synthetic steroidal compound (derivatized from DHT backbone) classified as a SARM, though its primary mechanism is distinct from conventional non-steroidal SARMs. YK-11 acts as a partial AR agonist but uniquely induces expression of follistatin (FST), a myostatin (GDF-8) antagonist. Myostatin is a negative regulator of muscle mass; by increasing follistatin, YK-11 may promote skeletal muscle hypertrophy via dual AR-mediated and myostatin-inhibition pathways. This mechanism is supported by in vitro data showing increased myogenic differentiation in C2C12 myoblasts. No human clinical trials have been conducted as of current data.
Evidence Level
In Vitro - Cell
5 studies published
Pharmacology
Molecular Weight
430.6 g/mol
Half-Life
Estimated 6-10 hours (no human PK data)
Bioavailability
Unknown; preclinical only