| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Integrative Physiology |
From the Departments of Medicine and Pharmacology (H.W.K., T.F.) and the Department of Pharmacology (M.U.-F.), University of Illinois at Chicago; and the Woodruff School of Mechanical Engineering (A.L., R.G.), Georgia Institute of Technology, Atlanta.
Correspondence to Tohru Fukai, MD, PhD, Departments of Medicine and Pharmacology, University of Illinois at Chicago, 835 S. Wolcott, M/C868, E403 MSB, Chicago, IL 60612. E-mail tfukai{at}uic.edu; and Masuko Ushio-Fukai, PhD, Department of Pharmacology, University of Illinois at Chicago, 835 S. Wolcott, M/C868, E403 MSB, Chicago, IL 60612. E-mail mfukai@uic.edu
Neovascularization is an important physiological repair mechanism in response to ischemic injury, and its process is dependent on reactive oxygen species (ROS). Overproduction of superoxide anion (O2·–) rather contributes to various cardiovascular diseases. The extracellular superoxide dismutase (ecSOD) is one of the major antioxidant enzymes against O2·– in blood vessels; however, its role in neovascularization induced by tissue ischemia is unknown. Here we show that hindlimb ischemia of mice stimulates a significant increase in ecSOD activity in ischemic tissues where ecSOD protein is highly expressed at arterioles. In mice lacking ecSOD, ischemia-induced increase in blood flow recovery, collateral vessel formation, and capillary density are significantly inhibited. Impaired neovascularization in ecSOD–/– mice is associated with enhanced O2·– production, TUNEL-positive apoptotic cells and decreased levels of NO2–/NO3– and cGMP in ischemic tissues as compared with wild-type mice, and it is rescued by infusion of the SOD mimetic tempol. Recruitment of inflammatory cells into ischemic tissues as well as numbers of inflammatory cells and endothelial progenitor cells (c-kit+/CD31+ cells) in both peripheral blood and bone marrow (BM) are significantly reduced in these knockout mice. Of note, ecSOD expression is markedly increased in BM after ischemia. NO2–/NO3– and cGMP levels are decreased in ecSOD–/– BM. Transplantation of wild-type BM into ecSOD–/– mice rescues the defective neovascularization. Thus, ecSOD in BM and ischemic tissues induced by hindlimb ischemia may represent an important compensatory mechanism that blunts the overproduction of O2·–, which may contribute to reparative neovascularization in response to ischemic injury.
Key Words: superoxide dismutase reactive oxygen species neovascularization bone marrow endothelial progenitor cells
Related Article:
Circ. Res. 2007 101: 331-332.
This article has been cited by other articles:
![]() |
R. Reed, B. Potter, E. Smith, R. Jadhav, P. Villalta, H. Jo, and P. Rocic Redox-sensitive Akt and Src regulate coronary collateral growth in metabolic syndrome Am J Physiol Heart Circ Physiol, June 1, 2009; 296(6): H1811 - H1821. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Dai, Y. He, H. Zhang, L. Yu, T. Wan, Z. Xu, D. Jones, H. Chen, and W. Min Endothelial-Specific Expression of Mitochondrial Thioredoxin Promotes Ischemia-Mediated Arteriogenesis and Angiogenesis Arterioscler Thromb Vasc Biol, April 1, 2009; 29(4): 495 - 502. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Qin, M. C. Gongora, K. Ozumi, S. Itoh, K. Akram, M. Ushio-Fukai, D. G. Harrison, and T. Fukai Role of Menkes ATPase in Angiotensin II-Induced Hypertension: A Key Modulator for Extracellular Superoxide Dismutase Function Hypertension, November 1, 2008; 52(5): 945 - 951. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Urao, H. Inomata, M. Razvi, H. W. Kim, K. Wary, R. McKinney, T. Fukai, and M. Ushio-Fukai Role of Nox2-Based NADPH Oxidase in Bone Marrow and Progenitor Cell Function Involved in Neovascularization Induced by Hindlimb Ischemia Circ. Res., July 18, 2008; 103(2): 212 - 220. [Abstract] [Full Text] [PDF] |
||||
![]() |
A.-L. Levonen, E. Vahakangas, J. K. Koponen, and S. Yla-Herttuala Antioxidant Gene Therapy for Cardiovascular Disease: Current Status and Future Perspectives Circulation, April 22, 2008; 117(16): 2142 - 2150. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Itoh, H. W. Kim, O. Nakagawa, K. Ozumi, S. M. Lessner, H. Aoki, K. Akram, R. D. McKinney, M. Ushio-Fukai, and T. Fukai Novel Role of Antioxidant-1 (Atox1) as a Copper-dependent Transcription Factor Involved in Cell Proliferation J. Biol. Chem., April 4, 2008; 283(14): 9157 - 9167. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. S. Wolin ecSOD Controls the Delicate Balance of Reactive Oxygen Species in Bone Marrow and Ischemic Tissue Needed for Neovascularization Circ. Res., August 17, 2007; 101(4): 331 - 332. [Full Text] [PDF] |
||||
|
Circulation Research Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2007 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |