Smad4 restricts differentiation to promote expansion of satellite cell derived progenitors during skeletal muscle regeneration.
Nicole D ParisAndrew SorokaAlanna KloseWenxuan LiuJoe V ChakkalakalPublished in: eLife (2016)
Skeletal muscle regenerative potential declines with age, in part due to deficiencies in resident stem cells (satellite cells, SCs) and derived myogenic progenitors (MPs); however, the factors responsible for this decline remain obscure. TGFβ superfamily signaling is an inhibitor of myogenic differentiation, with elevated activity in aged skeletal muscle. Surprisingly, we find reduced expression of Smad4, the downstream cofactor for canonical TGFβ superfamily signaling, and the target Id1 in aged SCs and MPs during regeneration. Specific deletion of Smad4 in adult mouse SCs led to increased propensity for terminal myogenic commitment connected to impaired proliferative potential. Furthermore, SC-specific Smad4 disruption compromised adult skeletal muscle regeneration. Finally, loss of Smad4 in aged SCs did not promote aged skeletal muscle regeneration. Therefore, SC-specific reduction of Smad4 is a feature of aged regenerating skeletal muscle and Smad4 is a critical regulator of SC and MP amplification during skeletal muscle regeneration.
Keyphrases
- skeletal muscle
- stem cells
- transforming growth factor
- epithelial mesenchymal transition
- insulin resistance
- poor prognosis
- mesenchymal stem cells
- machine learning
- signaling pathway
- induced apoptosis
- oxidative stress
- deep learning
- patient safety
- transcription factor
- quality improvement
- long non coding rna
- cell cycle arrest
- bone marrow
- risk assessment
- emergency medicine