Je. Albina et al., HIF-1 expression in healing wounds: HIF-1 alpha induction in primary inflammatory cells by TNF-alpha, AM J P-CELL, 281(6), 2001, pp. C1971-C1977
The expression of the hypoxia-responsive transcription factor hypoxia-induc
ible factor (HIF)-1 during acute inflammation was investigated in experimen
tal wounds. HIF-1 alpha mRNA was maximally expressed in wound cells 6 h aft
er injury. HIF-1 alpha protein was detectable in wound cells 1 and 5 days a
fter injury. Cells from 1-day-old wounds were not hypoxic, as determined by
lack of pimonidazole hydrochloride adduct formation. Tumor necrosis factor
(TNF)-alpha, but not interleukin-1 beta, increased the HIF-1a protein cont
ent of cells isolated 1 and 5 days after injury, and also of glycogen-elici
ted peritoneal cells, but not HIF-1 alpha mRNA. HIF-1 alpha did not accumul
ate in TNF-alpha -treated HeLa, NIH/3T3, NR8383, or RAW 264.7 cells. Nitric
oxide from S-nitrosoglutathione did not induce HIF-1 alpha accumulation or
modulate the response to TNF-alpha. TNF-alpha did not increase oxygen cons
umption or result in the production of reactive oxygen intermediates by day
1 wound cells. Vascular endothelial growth factor mRNA in wound cells peak
ed 24 h after wounding. HIF-1 expression in early wounds may contribute to
the regulation of inducible nitric oxide synthase and vascular endothelial
growth factor, two HIF-1-responsive genes intimately related to the process
of repair.