Published in

Karger Publishers, Neonatology, 4(97), p. 346-354, 2009

DOI: 10.1159/000261018

Links

Tools

Export citation

Search in Google Scholar

Effect of Oxygen on the Expression of Hypoxia-Inducible Factors in Human Fetal Lung Explants

This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

<i>Background:</i> Fetal lung development requires proper coordination between lung epithelial and vascular morphogenesis. A major determinant in lung vascular development is vascular endothelial growth factor (VEGF), which is regulated by hypoxia-inducible factors (HIFs). VEGF is expressed in the airway epithelium, while its receptors (VEGFRs) are expressed in the pulmonary mesenchyme. The hypoxic environment in utero is beneficial for fetal organogenesis, especially vascular development. However, little is known about the expression of HIFs and VEGFR-2 in the human fetal lung in vitro. <i>Objectives:</i> The purpose of this study was to investigate the effects of hypoxia on fetal lung morphology and mRNA expression of VEGF, VEGFR-2, HIF-2α, and HIF-3α. <i>Methods:</i> An explant culture technique was used to study the effects of normoxic and hypoxic conditions on human fetal lung. <i>Results:</i> The morphology remained largely unchanged in explants cultured under hypoxic or normoxic conditions. Quantitative RT-PCR showed that the mRNA expression of VEGF-A, but not VEGFR-2 is upregulated in explants cultured at 1.5% compared with 21% oxygen. We observed a nonsignificant increase in HIF-2α and HIF-3α mRNA expression in explants cultured at 1.5% oxygen. These data suggest that the mRNA expression of VEGF, and possibly HIF-2α and HIF-3α, is regulated by hypoxia in the developing human lung. <i>Conclusion:</i> This lung explant culture model appears to be a valuable model to unravel the molecular mechanisms of human lung development.