Canstatin inhibits isoproterenol-induced apoptosis through preserving mitochondrial morphology in differentiated H9c2 cardiomyoblasts.
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.
Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Higashi 23 Bancho 35-1, Towada, Aomori, 034-8628, Japan. mokada@vmas.kitasato-u.ac.jp.
Muneyoshi
M
Okada
Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Higashi 23 Bancho 35-1, Towada, Aomori, 034-8628, Japan.
Suiri
S
Morioka
Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Higashi 23 Bancho 35-1, Towada, Aomori, 034-8628, Japan.
Hiroki
H
Kanazawa
Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Higashi 23 Bancho 35-1, Towada, Aomori, 034-8628, Japan.
Hideyuki
H
Yamawaki
D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D024141:Collagen Type IV / Q000378:metabolism*; D051379:Mice; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D063154:Mitochondrial Dynamics / Q000187:drug effects; D032446:Myoblasts / Q000187:drug effects* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects
D020533:Angiogenesis Inhibitors; D024141:Collagen Type IV; D017382:Reactive Oxygen Species; D053148:Caspase 3
Apoptosis; Canstatin; Dynamin related protein 1; Isoproterenol; Mitochondrial fission