Editors' ChoiceMuscle Disease

Elucidating Satellite Stem Cell Biology

Sci. Signal.  23 Dec 2014:
Vol. 7, Issue 357, pp. ec358
DOI: 10.1126/scisignal.aaa5180

In patients affected by the muscle-wasting disease, Duchenne muscular dystrophy (DMD), the regenerative ability of skeletal muscle becomes progressively impaired and fibrotic tissue accumulates, leading to a severe reduction in muscle function. Biressi et al. showed that satellite cells, the stem cells resident in skeletal muscle, have a compromised myogenic potential in the mdx mouse model of DMD. These muscle stem cells showed enhanced expression of fibrogenic rather than myogenic genes. The authors linked enhanced Wnt signaling with an increase in the expression of the gene encoding transforming growth factor–β2 (TGFβ2) in dystrophic muscle and suggest that the resulting increase in TGFβ activity may be responsible for the aberrant behavior of the satellite stem cells.

S. Biressi, E. H. Miyabara, S. D. Gopinath, P. M. M. Carlig, T. A. Rando, A Wnt-TGFβ2 axis induces a fibrogenic program in muscle stem cells from dystrophic mice. Sci. Transl. Med. 6, 267ra176 (2014). [Abstract]