title: Inhibiting NF-κB in the developing lung disrupts angiogenesis and alveolarization.
abstract: Bronchopulmonary dysplasia (BPD), a chronic lung disease of infancy, is characterized by arrested alveolar development. Pulmonary angiogenesis, mediated by the vascular endothelial growth factor (VEGF) pathway, is essential for alveolarization. However, the transcriptional regulators mediating pulmonary angiogenesis remain unknown. We previously demonstrated that NF-κB, a transcription factor traditionally associated with inflammation, plays a unique protective role in the neonatal lung. Therefore, we hypothesized that constitutive NF-κB activity is essential for postnatal lung development. Blocking NF-κB activity in 6-day-old neonatal mice induced the alveolar simplification similar to that observed in BPD and significantly reduced pulmonary capillary density. Studies to determine the mechanism responsible for this effect identified greater constitutive NF-κB in neonatal lung and in primary pulmonary endothelial cells (PEC) compared with adult. Moreover, inhibiting constitutive NF-κB activity in the neonatal PEC with either pharmacological inhibitors or RNA interference blocked PEC survival, decreased proliferation, and impaired in vitro angiogenesis. Finally, by chromatin immunoprecipitation, NF-κB was found to be a direct regulator of the angiogenic mediator, VEGF-receptor-2, in the neonatal pulmonary vasculature. Taken together, our data identify an entirely novel role for NF-κB in promoting physiological angiogenesis and alveolarization in the developing lung. Our data suggest that disruption of NF-κB signaling may contribute to the pathogenesis of BPD and that enhancement of NF-κB may represent a viable therapeutic strategy to promote lung growth and regeneration in pulmonary diseases marked by impaired angiogenesis.
authors.affiliation: Division of Critical Care Medicine, Department of Pediatrics, Stanford University School of Medicine, 300 Pasteur Dr., Stanford, CA 94305-5208, USA.
authors.forename: Cristiana
authors.initials: C
authors.lastname: Iosef
authors.forename: Tero-Pekka
authors.initials: TP
authors.lastname: Alastalo
authors.forename: Yanli
authors.initials: Y
authors.lastname: Hou
authors.forename: Chihhsin
authors.initials: C
authors.lastname: Chen
authors.forename: Eloa S
authors.initials: ES
authors.lastname: Adams
authors.forename: Shu-Chen
authors.initials: SC
authors.lastname: Lyu
authors.forename: David N
authors.initials: DN
authors.lastname: Cornfield
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Alvira
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001997:Bronchopulmonary Dysplasia / Q000503:physiopathology; D049109:Cell Proliferation / Q000187:drug effects; D004730:Endothelium, Vascular / Q000254:growth & development / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000098:blood supply* / Q000254:growth & development / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018919:Neovascularization, Physiologic / Q000187:drug effects; D009570:Nitriles / Q000494:pharmacology; D011650:Pulmonary Alveoli / Q000254:growth & development / Q000502:physiology; D034741:RNA, Small Interfering / Q000235:genetics; D015398:Signal Transduction; D013450:Sulfones / Q000494:pharmacology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000235:genetics / Q000378:metabolism*
chemical_list: C434003:3-(4-methylphenylsulfonyl)-2-propenenitrile; D016328:NF-kappa B; D009570:Nitriles; D034741:RNA, Small Interfering; D013450:Sulfones; D040301:Vascular Endothelial Growth Factor Receptor-2