Novel approaches to activin pathway neutralization and glucocorticoid assessment in management of muscle and bone loss

Muscle and bone loss with age can be worsened by inactivity, chronic illness and some medicines, raising the risk of poorer mobility, falls and fractures. A doctoral project studied a treatment to limit this loss and a way to measure cortisol and related steroids, whose excess can weaken muscle and bone.

One part tested a ligand-trapping agent intended to neutralise activin A, myostatin and GDF11, proteins that normally restrict muscle growth and bone building. In mice with a paralysed hindlimb, it built muscle and protected against loss of bone mass, strength and structure in that limb. Cell studies showed the activin pathway communicates with other routes relevant to bone building; the trapping agent kept them intact, while an antibody blocking activin receptors altered them. The findings support ligand neutralisation for preserving and building muscle and bone.