Inhibition of activin A ameliorates skeletal muscle injury and rescues contractile properties by inducing efficient remodeling in female mice.

Activin A, a member of the transforming growth factor-β superfamily, provides pleiotropic regulation of fibrosis and inflammation. We aimed at determining whether selective inhibition of activin A would provide a regenerative benefit. The introduction of activin A into normal muscle increased the expression of inflammatory and muscle atrophy genes Tnf, Tnfrsf12a, Trim63, and Fbxo32 by 3.

Follistatin: a novel therapeutic for the improvement of muscle regeneration.

Follistatin (FST) is a member of the tissue growth factor β family and is a secreted glycoprotein that antagonizes many members of the family, including activin A, growth differentiation factor 11, and myostatin. The objective of this study was to explore the use of an engineered follistatin therapeutic created by fusing FST315 lacking heparin binding activity to the N terminus of a murine IgG1 Fc (FST315-ΔHBS-Fc) as a systemic therapeutic agent in models of muscle injury. Systemic administration of this molecule was found to increase body weight and lean muscle mass after weekly administration in normal mice.