Both early and late protection by ischemic preconditioning (PC) is elicited by a number of triggers and mediators. Among them, nitric oxide (NO) derived from NO synthase is believed to be responsible for both early and late PC. The downstream signaling pathways that translate into synthesis of cardioprotective proteins remain largely unknown. The central hypothesis of this proposal is that late PC is the result of NOS upregulation by initial ischemic stimulus via a signaling cascade involving PKC and NFkappaB with mitochondrial KATP channel as the end effector of protection. The uniqueness of this study is that it identifies the mitochondrial KATP channel as the end effector of protection both in early and late PC. To address this issue, we propose to determine whether 1) PC by mitoKATP channel is due to NO formation via iNOS upregulation, 2) late PC by mitoKATP channel involves NFkappaB-iNOS pathway, 3) late PC is mediated by opening of mitoKATP channel via PKC signaling pathway, 4) PKC stimulation is caused by NO during mitoKATP channel activation, 5) late PC by mitoKATP channel reduces cell injury by inhibiting apoptosis, and 6) late PC by mitoKATP channel attenuates ischemic injury by maintaining mitochondrial membrane potential. To accomplish these aims, we will use normal rats and transgenic mice lacking iNOS, eNOS, nNOS, NFkappaB, PKCdelta and PKCepsilon. The role of PKCdelta and PKCepsilon in mitoKATP-mediated protection will be evaluated in genetically manipulated mice. NOS knockout mice will be important to rule out nonspecific effects of NO on mitoKATP channel. A wide range of multidisciplinary techniques including biochemistry, cell biology, molecular biology, electron microscopy, immunocytochemistry and pharmacological approaches will be used to integrate the information at the cell level with the function at the organ level. Isoform-specific PKC translocation, NOS mRNA, isoform expression and activities will be examined both during early and late PC. This proposal is the first which will identify mitoKATP channel as an end effector of protection during PC and will have important implications for designing pharmacological and gene therapeutic interventions against the lethal ischemia.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL070062-03
Application #
6730602
Study Section
Special Emphasis Panel (ZRG1-ECS (01))
Program Officer
Przywara, Dennis
Project Start
2002-04-01
Project End
2007-03-31
Budget Start
2004-04-01
Budget End
2005-03-31
Support Year
3
Fiscal Year
2004
Total Cost
$483,124
Indirect Cost
Name
University of Cincinnati
Department
Pathology
Type
Schools of Medicine
DUNS #
041064767
City
Cincinnati
State
OH
Country
United States
Zip Code
45221
Haider, Khawaja Husnain; Ashraf, Muhammad (2012) Preconditioning approach in stem cell therapy for the treatment of infarcted heart. Prog Mol Biol Transl Sci 111:323-56
Haider, Husnain Kh; Ashraf, Muhammad (2010) Preconditioning and stem cell survival. J Cardiovasc Transl Res 3:89-102
Jiang, Shujia; Kh Haider, Husnain; Ahmed, Rafeeq P H et al. (2008) Transcriptional profiling of young and old mesenchymal stem cells in response to oxygen deprivation and reparability of the infarcted myocardium. J Mol Cell Cardiol 44:582-96
Pasha, Zeeshan; Wang, Yigang; Sheikh, Riazuddin et al. (2008) Preconditioning enhances cell survival and differentiation of stem cells during transplantation in infarcted myocardium. Cardiovasc Res 77:134-42
Haider, Husnain Kh; Ashraf, Muhammad (2008) Strategies to promote donor cell survival: combining preconditioning approach with stem cell transplantation. J Mol Cell Cardiol 45:554-66
Dai, Ying; Ashraf, Muhammad; Zuo, Shi et al. (2008) Mobilized bone marrow progenitor cells serve as donors of cytoprotective genes for cardiac repair. J Mol Cell Cardiol 44:607-17
Haider, Husnain K; Ye, Lei; Ashraf, Muhammad (2007) Skeletal muscle derived stem cells for myocardial repair. Recent Pat Cardiovasc Drug Discov 2:205-13
Dai, Ying; Xu, Meifeng; Wang, Yigang et al. (2007) HIF-1alpha induced-VEGF overexpression in bone marrow stem cells protects cardiomyocytes against ischemia. J Mol Cell Cardiol 42:1036-44
Xu, Meifeng; Uemura, Ryota; Dai, Ying et al. (2007) In vitro and in vivo effects of bone marrow stem cells on cardiac structure and function. J Mol Cell Cardiol 42:441-8