| First Author | Miyazaki Y | Year | 2011 |
| Journal | Arterioscler Thromb Vasc Biol | Volume | 31 |
| Issue | 5 | Pages | 1124-32 |
| PubMed ID | 21330607 | Mgi Jnum | J:191489 |
| Mgi Id | MGI:5461813 | Doi | 10.1161/ATVBAHA.111.224519 |
| Citation | Miyazaki Y, et al. (2011) C/EBP homologous protein deficiency attenuates myocardial reperfusion injury by inhibiting myocardial apoptosis and inflammation. Arterioscler Thromb Vasc Biol 31(5):1124-32 |
| abstractText | OBJECTIVE: To investigate whether and how the endoplasmic reticulum (ER) stress-induced, CCAAT/enhancer-binding protein-homologous protein (CHOP)-mediated pathway regulates myocardial ischemia/reperfusion injury. METHODS AND RESULTS: Wild-type and chop-deficient mice underwent 50 minutes of left coronary artery occlusion followed by reperfusion. Expression of chop and spliced x-box binding protein-1 (sxbp1) mRNA was rapidly and significantly increased in reperfused myocardium of wild-type mice. chop-deficient mice exhibited markedly reduced injury size after reperfusion compared with wild-type mice, accompanied by a decreasing number of terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive cardiomyocytes. Interestingly, myocardial inflammation, as assessed by expression of inflammatory cytokines and chemokines and numbers of infiltrated inflammatory cells, was also attenuated in chop-deficient mice. Moreover, expression of interleukin-6 mRNA in response to lipopolysaccharide was enhanced by simultaneous stimulation with thapsigargin, a potent ER stressor, in wild-type cardiomyocytes but not in chop-deficient cardiomyocytes. Finally, we found that superoxide was produced in reperfused myocardium and that intravenous administration of edaravone, a free radical scavenger, immediately before reperfusion significantly suppressed the superoxide overproduction and subsequent expression of sxbp1 and chop mRNA, followed by reduced injury size in wild-type mice. CONCLUSIONS: The ER stress-induced, CHOP-mediated pathway, which is activated in part by superoxide overproduction after reperfusion, exacerbates myocardial ischemia/reperfusion injury by inducing cardiomyocyte apoptosis and myocardial inflammation. |
