Background
Hyperoxia has been shown to improve wound healing; however, the mechanism for such
therapeutic effects of oxygen remains hypothetical. Rac 1 regulates a wide variety
of cellular activities, including cell proliferation and migration, and also is a
key regulator for the activity of the nicotinamide dinucleotide phosphate oxidase
the enzyme complex responsible for the production of a large fraction of cellular
superoxide.
Methods
We generated transgenic mice that express either the cDNA of a constitutively active
mutant of human Rac 1 (V12 mutant or Rac CA) or the dominant negative isoform (V12
and N17 mutant or Rac DN) in the blood vessels using mouse vascular smooth muscle
promoter for α-actin. We placed 2 wounds of 6 mm in diameter at the middorsal region
of each mouse and allowed about 3 weeks for the wounds to heal.
Results
The size of the wounds in Rac CA transgenic mice was reduced relative to wild type
mice; healing of Rac DN mice was slower than wild type and Rac CA (P < .05). Blood vessel formation appeared faster in Rac CA mice, a finding associated
with enhanced expression of some angiogenic growth factors.
Conclusion
The current studies suggest that Rac 1 activation accelerates the wound healing process
and is associated with more efficient angiogenesis at the wound site.
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Article info
Publication history
Accepted:
June 8,
2004
Columbus, Ohio, and Durham, NCIdentification
Copyright
© 2005 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
