Published Online
on July 19, 2004

A more recent version of this article appeared on October 19, 2004

This Article Full Text (PDF) All Versions of this Article: 110/16/2484    most recent 01.CIR.0000137969.87365.05v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Luo, J.-D. Articles by Chen, A. F. Search for Related Content PubMed PubMed Citation Articles by Luo, J.-D. Articles by Chen, A. F. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Medline Plus Health Information Genes and Gene Therapy Hazardous Substances DB GLUCOSE NITRIC OXIDE Related Collections Cardiovascular Pharmacology Angiogenesis Animal models of human disease Type 1 diabetes Gene therapy Oxidant stress Endothelium/vascular type/nitric oxide

Submitted on December 11, 2002
Revised on June 3, 2004
Accepted on June 14, 2004

Gene Therapy of Endothelial Nitric Oxide Synthase and Manganese Superoxide Dismutase Restores Delayed Wound Healing in Type 1 Diabetic Mice

Jian-Dong Luo MD, PhD, Ying-Ying Wang MD, Wei-Ling Fu MD, PhD, Jun Wu MD, PhD, and Alex F. Chen MD, PhD^*

From the Departments of Pharmacology and Neurology and the Neuroscience Program (J.-D.L., Y.-Y.W., A.F.C.), Michigan State University, East Lansing; Department of Pharmacology, Guangzhou Medical College, Guangzhou, China (J.-D.L.); and Southwestern Hospital, Third Military Medical University, Chongqing, China (Y.-Y.W., W.-L.F., J.W., A.F.C.).

^* To whom correspondence should be addressed. E-mail: chenal{at}msu.edu.

Background--Nitric oxide (NO) deficiency contributes to diabetic wound healing impairment. The present study tested the hypothesis that increased cutaneous superoxide (O₂^-) levels in type 1 diabetic mice cause NO deficiency and delayed wound healing.

Methods and Results--Wound healing was markedly delayed in streptozotocin-induced type 1 diabetic mice compared with the normal controls. There were significantly reduced levels of endothelial NO synthase (eNOS) protein and constitutive NOS activity in diabetic wounds, whereas O₂^- levels were markedly increased. A single regimen of cutaneous gene therapy of eNOS or manganese superoxide dismutase (MnSOD) restored such healing delay, with a concomitant suppression of wound O₂^- levels and augmentation of both eNOS protein and constitutive NOS activity. Gene therapy of MnSOD also increased cutaneous MnSOD activity. Cutaneous O₂^- levels were also increased in Ins2^Akita diabetic mice. In vitro glucose treatment of cutaneous tissues from normal mice for 24 hours increased O₂^- levels in a concentration-dependent manner. The enhanced cutaneous O₂^- levels induced by high glucose in both normal and diabetic mice were abolished by the NADPH oxidase inhibitor apocynin and the protein kinase C inhibitor chelerythrine. Furthermore, ex vivo gene transfer of dominant-negative HA-tagged N17Rac1, which inhibits NADPH oxidase subunit Rac1, significantly inhibited cutaneous O₂^- formation induced by high glucose in both normal and Ins2^Akita diabetic mice.

Conclusions--These results indicate that hyperglycemia augments cutaneous O₂^- levels, at least in part, via NADPH oxidase and protein kinase C pathways, resulting in impaired wound healing in type 1 diabetic mice. Gene therapy strategies aimed at restoring cutaneous NO bioavailability may provide an effective means to ameliorate delayed diabetic wound healing.

Key words: wound healing • nitric oxide • superoxides • diabetes mellitus • gene therapy

This article has been cited by other articles:

				J. Yang, P. H. Lane, J. S. Pollock, and P. K Carmines PKC-dependent superoxide production by the renal medullary thick ascending limb from diabetic rats Am J Physiol Renal Physiol, November 1, 2009; 297(5): F1220 - F1228. [Abstract] [Full Text] [PDF]

				J.-D. Luo, T.-P. Hu, L. Wang, M.-S. Chen, S.-M. Liu, and A. F. Chen Sonic hedgehog improves delayed wound healing via enhancing cutaneous nitric oxide function in diabetes Am J Physiol Endocrinol Metab, August 1, 2009; 297(2): E525 - E531. [Abstract] [Full Text] [PDF]

				L. Tie, X.-J. Li, X. Wang, K. M. Channon, and A. F. Chen Endothelium-specific GTP cyclohydrolase I overexpression accelerates refractory wound healing by suppressing oxidative stress in diabetes Am J Physiol Endocrinol Metab, June 1, 2009; 296(6): E1423 - E1429. [Abstract] [Full Text] [PDF]

				Y. Kanetsuna, K. Takahashi, M. Nagata, M. A. Gannon, M. D. Breyer, R. C. Harris, and T. Takahashi Deficiency of Endothelial Nitric-Oxide Synthase Confers Susceptibility to Diabetic Nephropathy in Nephropathy-Resistant Inbred Mice Am. J. Pathol., May 1, 2007; 170(5): 1473 - 1484. [Abstract] [Full Text] [PDF]

				D.-D. Chen and A. F. Chen CuZn Superoxide Dismutase Deficiency: Culprit of Accelerated Vascular Aging Process Hypertension, December 1, 2006; 48(6): 1026 - 1028. [Full Text] [PDF]

				R. A. Kowluru, L. Atasi, and Y.-S. Ho Role of mitochondrial superoxide dismutase in the development of diabetic retinopathy. Invest. Ophthalmol. Vis. Sci., April 1, 2006; 47(4): 1594 - 1599. [Abstract] [Full Text] [PDF]