Canstatin inhibits isoproterenol-induced apoptosis through preserving mitochondrial morphology in differentiated H9c2 cardiomyoblasts

Apoptosis. 2016 Aug;21(8):887-95. doi: 10.1007/s10495-016-1262-1.


Canstatin, a non-collagenous fragment, is cleaved from type IV collagen α2 chain, an essential component of basement membrane surrounding cardiomyocytes. Although canstatin is known as an endogenous anti-angiogenic factor, its effects on cardiomyocytes have not been clarified. This study examined the effects of canstatin on isoproterenol-induced apoptosis in differentiated H9c2 cardiomyoblasts. Retinoic acid was used to differentiate H9c2 myoblast to cardiomyocyte-like phenotype. Cell viability was determined by a cell counting assay. Western blotting was performed to detect expression of cleaved casepase-3 and phosphorylation of dynamin related protein (Drp)1 at Ser637 which regulates mitochondrial fission. Mito Sox Red staining was performed to examine a mitochondria-dependent production of reactive oxygen species (ROS). Mitochondrial morphology was detected by Mito Tracker Red staining. Isoproterenol (100 μM, 48 h) significantly decreased cell viability and increased cleaved caspase-3 expression, which were inhibited by canstatin (10-250 ng/ml) in a concentration-dependent manner. Canstatin suppressed the isoproterenol-induced mitochondrial fission but not ROS. Canstatin also inhibited the isoproterenol-induced dephosphorylation of Drp1 at Ser637. In conclusion, canstatin inhibits isoproterenol-induced apoptosis through the inhibition of mitochondrial fission via the suppression of dephosphorylation of Drp1 at Ser637 in differentiated H9c2 cardiomyoblasts.

Keywords: Apoptosis; Canstatin; Dynamin related protein 1; Isoproterenol; Mitochondrial fission.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiogenesis Inhibitors / pharmacology*
  • Animals
  • Apoptosis / drug effects*
  • Caspase 3 / metabolism
  • Cell Differentiation / drug effects*
  • Cell Line
  • Cell Survival / drug effects
  • Collagen Type IV / metabolism*
  • Mice
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Mitochondrial Dynamics / drug effects
  • Myoblasts / drug effects*
  • Myoblasts / metabolism
  • Myocytes, Cardiac / drug effects*
  • Myocytes, Cardiac / metabolism
  • Phosphorylation / drug effects
  • Rats
  • Reactive Oxygen Species / metabolism
  • Signal Transduction / drug effects


  • Angiogenesis Inhibitors
  • Collagen Type IV
  • Reactive Oxygen Species
  • Caspase 3