Research Project
Grant-in-Aid for Scientific Research (C)
Apop is a protein originally isolated as a factor of unlkown function from cultured atherosclerotic smooth muscle cells. We found recently that expression of Apop induces apoptosis of vascular smooth muscle cells (SMC) in culture by releasing cytochrome c from mitochondria. Release of cytochrome c from the permeability transition pore (PTP) is believed to play an important role in ischemia/reeoxygenation-induced cardiomyocyte apoptosis, which contributes the development of heart failure following balloon angioplasty after myocardial infarction. This study was performed to investigate the role of Apop in hypoxia/reoxygenation-induced death of cardiomyocytes. Neonatal cardiomyccybas were prepared from ventricles of 2- to 3-day-old Sprague-Dawley rats and maintained in DMEM supplemented with 10% fetal bovine serum. Antisense plasmid to prevent Apop expression or control vector was introduced into cardiomyocybes using an electroporator. Cells were then incubated in hypoxic condition (1% O2 … More ) for 48 hours followed by 2 hours of reoxygenation. Cell viability was assessed by MTT assay. Anti-apoptotic bcl-2 family proteins, such as bcl-2 and bcl-xL were unable to prevent Apop-induced apoptosis, while it was prevented by inhibitors of cyclophilin D, an important component of PTP. These findings indicate that the apoptosis induced by Apop is not mediated by bcl-2 family-related channels, but may require PIP on mitochondrial membrane. Introduction of siRNA targeted toward Apop transcript into cultured cells almost completely abolished the green fluorescence of Apop-GFP fusion protein, indicating that siRNA prevents the expression of Apop. The inhibitory activity of siRNA was also confirmed by Western blot analysis. In the experiments of hypoxia/reoxygenation-induced cell death, introduction of siRNA inhibited the activation of caspase-cascade and the death of cultured cardiomyccytes, whereas introduction of control siRNA affected neither caspase activity nor viability; Inhibition of Apop expression prevented hypoxia/reoxygenation-induced death of cardiomyocytes, suggesting that Apop protein may play roles in the development of cardiac diseases following ischemia-reperfusion injury. Less
All 2008 2007 2006
All Journal Article (21 results) (of which Peer Reviewed: 10 results) Presentation (17 results) Book (1 results)
The American journal of pathology 172(3)
Pages: 818-829
American journal of pathology 172(3)
Cellular and molecular life sciences 65(3)
Pages: 354-358
The American journal of pathology (印刷中)
Geriatrics and Gerontology International 7
Pages: 363-370
Arteriosclerosis, thrombosis, and vascular biology 27(10)
Pages: 2184-2190
FEBS letters 581(3)
Pages: 427-432
Hypertension Research 30(6)
Pages: 563-571
10020020786
FEBS Letters 581(3)
Pages: 427-427
Journal of Biological Chemistry 281(33)
Pages: 23899-23907
Hypertension Research 29(4)
Pages: 285-294
Pages: 217-225
Diabetes 55(6)
Pages: 1660-1665
10017985701
10017985402
