Myostatin (also known as Growth Differentiation Factor 8, abbreviated GDF-8) is a myocin, a myocyte-produced and released protein that acts on the autocrine function of muscle cells to inhibit myogenesis, resulting in muscle cell growth.
Myostatin is an endogenous, negative regulator of muscle growth that determines both the number and size of muscle fibers. Experimental models of muscle growth and muscle regeneration have linked myostatin as an important mediator of catabolic pathways in muscle cells. The inhibition of this pathway has proven to be a promising therapy for muscle wasting. Myostatin, also known as GDF8 (growth differentiation factor 8), belongs to the transforming growth factor-β superfamily of secreted growth and differentiation factors.