Action of obestatin in skeletal muscle repair: stem cell expansion, muscle growth, and microenvironment remodeling

Mol Ther. 2015 Jun;23(6):1003-1021. doi: 10.1038/mt.2015.40. Epub 2015 Mar 12.

Abstract

The development of therapeutic strategies for skeletal muscle diseases, such as physical injuries and myopathies, depends on the knowledge of regulatory signals that control the myogenic process. The obestatin/GPR39 system operates as an autocrine signal in the regulation of skeletal myogenesis. Using a mouse model of skeletal muscle regeneration after injury and several cellular strategies, we explored the potential use of obestatin as a therapeutic agent for the treatment of trauma-induced muscle injuries. Our results evidenced that the overexpression of the preproghrelin, and thus obestatin, and GPR39 in skeletal muscle increased regeneration after muscle injury. More importantly, the intramuscular injection of obestatin significantly enhanced muscle regeneration by simulating satellite stem cell expansion as well as myofiber hypertrophy through a kinase hierarchy. Added to the myogenic action, the obestatin administration resulted in an increased expression of vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor 2 (VEGFR2) and the consequent microvascularization, with no effect on collagen deposition in skeletal muscle. Furthermore, the potential inhibition of myostatin during obestatin treatment might contribute to its myogenic action improving muscle growth and regeneration. Overall, our data demonstrate successful improvement of muscle regeneration, indicating obestatin is a potential therapeutic agent for skeletal muscle injury and would benefit other myopathies related to muscle regeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / genetics
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / metabolism
  • Cell Proliferation / drug effects*
  • Disease Models, Animal
  • Female
  • Gene Expression Regulation
  • Ghrelin / pharmacology*
  • Injections, Intramuscular
  • Insulin Receptor Substrate Proteins / genetics
  • Insulin Receptor Substrate Proteins / metabolism
  • Mice
  • Muscle Development / drug effects
  • Muscle Fibers, Skeletal / drug effects*
  • Muscle Fibers, Skeletal / metabolism
  • Muscular Diseases / drug therapy*
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism
  • Regeneration / drug effects*
  • Satellite Cells, Skeletal Muscle / drug effects
  • Satellite Cells, Skeletal Muscle / metabolism
  • Vascular Endothelial Growth Factor Receptor-2 / genetics
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism
  • Vascular Endothelial Growth Factors / genetics
  • Vascular Endothelial Growth Factors / metabolism
  • p38 Mitogen-Activated Protein Kinases / genetics
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • GPR39 protein, mouse
  • Ghrelin
  • Insulin Receptor Substrate Proteins
  • Irs1 protein, mouse
  • Receptors, G-Protein-Coupled
  • Vascular Endothelial Growth Factors
  • Kdr protein, mouse
  • Vascular Endothelial Growth Factor Receptor-2
  • Proto-Oncogene Proteins c-akt
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2
  • p38 Mitogen-Activated Protein Kinases