We review the literature on the possible role of hypoxia in the etiology of IH, in particular, (1) the role of hypoxia inducible factor-1α (HIF-1α) and its downstream targets including GLUT-1 and VEGF; (2) the pathophysiological link between IH and retinopathy of prematurity; (3) hypoxic events in the early life including placental insufficiency, pre-eclampsia and low birthweight that have the potential to promote hypoxic stress; and (4) the evidence supporting the development of IH independent of HIF-1α.
Our results suggest that the HIF-1α gene polymorphisms are not associated with the development of pre-eclampsia in the studied Korean women population.
Here we studied whether two single nucleotide sequence variants, c.1744 C>T that changes residue 582 of HIF-1alpha from proline to serine (P582S) and c.1762 G>A that changes residue 588 of HIF-1alpha from alanine to threonine (A588T) in the exon 12 of the HIF1A gene, are associated with pre-eclampsia.
We speculate that if oxygen tension fails to increase, or trophoblasts do not detect this increase, HIF-1alpha and TGFbeta3 expression remain high, resulting in shallow trophoblast invasion and predisposing the pregnancy to pre-eclampsia.