title: Cardioprotection by HO-4038, a novel verapamil derivative, targeted against ischemia and reperfusion-mediated acute myocardial infarction.
abstract: Many cardiac interventional procedures, such as coronary angioplasty, stenting, and thrombolysis, attempt to reintroduce blood flow (reperfusion) to an ischemic region of myocardium. However, the reperfusion is accompanied by a complex cascade of cellular and molecular events resulting in oxidative damage, termed myocardial ischemia-reperfusion (I/R) injury. In this study, we evaluated the ability of HO-4038, an N-hydroxypiperidine derivative of verapamil, on the modulation of myocardial tissue oxygenation (Po(2)), I/R injury, and key signaling molecules involved in cardioprotection in an in vivo rat model of acute myocardial infarction (MI). MI was created in rats by ligating the left anterior descending coronary artery (LAD) for 30 min followed by 24 h of reperfusion. Verapamil or HO-4038 was infused through the jugular vein 10 min before the induction of ischemia. Myocardial Po(2) and the free-radical scavenging ability of HO-4038 were measured using electron paramagnetic resonance spectroscopy. HO-4038 showed a significantly better scavenging ability of reactive oxygen radicals compared with verapamil. The cardiac contractile functions in the I/R hearts were significantly higher recovery in HO-4038 compared with the verapamil group. A significant decrease in the plasma levels of creatine kinase and lactate dehydrogenase was observed in the HO-4038 group compared with the verapamil or untreated I/R groups. The left ventricular infarct size was significantly less in the HO-4038 (23 +/- 2%) compared with the untreated I/R (36 +/- 4%) group. HO-4038 significantly attenuated the hyperoxygenation (36 +/- 1 mmHg) during reperfusion compared with the untreated I/R group (44 +/- 2 mmHg). The HO-4038-treated group also markedly attenuated superoxide production, increased nitric oxide generation, and enhanced Akt and Bcl-2 levels in the reperfused myocardium. Overall, the results demonstrated that HO-4038 significantly protected hearts against I/R-induced cardiac dysfunction and damage through the combined beneficial actions of calcium-channel blocking, antioxidant, and prosurvival signaling activities.
authors.affiliation: Davis Heart and Lung Research Institute, The Ohio State Univ., Columbus, OH 43210, USA.
authors.forename: Iyyapu K
authors.initials: IK
authors.lastname: Mohan
authors.forename: Mahmood
authors.initials: M
authors.lastname: Khan
authors.forename: Sheik
authors.initials: S
authors.lastname: Wisel
authors.forename: Karuppaiyah
authors.initials: K
authors.lastname: Selvendiran
authors.forename: Arun
authors.initials: A
authors.lastname: Sridhar
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Carnes
authors.forename: Balazs
authors.initials: B
authors.lastname: Bognar
authors.forename: Tamás
authors.initials: T
authors.lastname: Kálai
authors.forename: Kálmán
authors.initials: K
authors.lastname: Hideg
authors.forename: Periannan
authors.initials: P
authors.lastname: Kuppusamy
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D015153:Blotting, Western; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism; D002316:Cardiotonic Agents; D002478:Cells, Cultured; D003402:Creatine Kinase / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D004594:Electrophysiology; D016166:Free Radical Scavengers / Q000494:pharmacology; D017665:Hydroxyl Radical / Q000378:metabolism; D008297:Male; D009203:Myocardial Infarction / Q000473:pathology / Q000517:prevention & control*; D015428:Myocardial Reperfusion Injury / Q000473:pathology / Q000517:prevention & control*; D009569:Nitric Oxide / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D013481:Superoxides / Q000378:metabolism; D014700:Verapamil / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000889:Anti-Arrhythmia Agents; D000975:Antioxidants; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D002316:Cardiotonic Agents; D016166:Free Radical Scavengers; C539017:HO-4038; D013481:Superoxides; D009569:Nitric Oxide; D017665:Hydroxyl Radical; D014700:Verapamil; D003402:Creatine Kinase