Hypoxia-inducible factor 1: Control of oxygen homeostasis in health and disease

Hypoxia-inducible factor 1 (HIF-1) is a transcriptional activator that mediates changes in gene expression in response to changes in cellular oxygen concentrations. HIF-1 is a heterodimer consisting of an oxygen-regulated HIF-1α subunit and a constitutively expressed HIF-1β subunit. In mice, complete HIF-1α deficiency results in embryonic lethality at midgestation because of cardiac and vascular malformations. Analyses of animal and cell culture models as well as human tissue have provided evidence that HIF-1 plays important roles in the pathophysiology of preeclampsia, intrauterine growth retardation, hypoxia-mediated pulmonary hypertension, and cancer. HIF-1 promotes neovascularization in response to myocardial or retinal ischemia by activating transcription of the gene encoding vascular endothelial growth factor. HIF-1 may also mediate the protective response to cerebral ischemia known as late-phase preconditioning.