Elk-1-mediated 15-lipoxygenase expression is required for hypoxia-induced pulmonary vascular adventitial fibroblast dynamics.
Acta Physiol (Oxf)
; 218(4): 276-289, 2016 12.
Article
en En
| MEDLINE
| ID: mdl-27174674
ABSTRACT
AIM:
15-Lipoxygenase (15-LO) is an important factor in the pathogenesis of pulmonary artery hypertension (PAH). However, the role of 15-LO in the adventitia of the pulmonary arterial wall is unclear. The aim of this study was to explore the role of 15-LO in the modulation of pulmonary adventitial fibroblast (PAF) dynamics.METHODS:
Rats were exposed to normoxic or hypoxic (fraction of inspired O2 = 0.12) treatments for 7 days. PAF proliferation and cell cycle alterations were measured by MTT assay, cell immunofluorescence, flow cytometry and Western blot analysis. The 15-LO promoter was analysed by luciferase reporter and ChIP assays.RESULTS:
Our results showed that hypoxia induced 15-LO expression in PAFs both in vivo and in vitro. In addition, hypoxia stimulated JNK phosphorylation in PAFs. Blocking 15-LO or JNK suppressed 15-LO-induced PAF proliferation and cell cycle alterations. The inhibition of p27kipl by gene silencing attenuated 15-LO-induced PAF proliferation and cell cycle alterations. Furthermore, JNK inhibition or Elk-1 knockdown suppressed hypoxia-induced 15-LO expression in PAFs. Luciferase reporter and ChIP assays revealed that the 15-LO promoter contains Elk-1-binding sites and also that Elk-1 increased the hypoxia-induced activity of the 15-LO promoter.CONCLUSION:
These results suggest that hypoxia promotes changes in the cellular dynamics of PAFs by inducing 15-LO expression, which leads to vascular adventitial remodelling. The modulation of p27kipl expression by 15-LO enhances PAF proliferation and cell cycle alterations. Furthermore, the JNK-dependent increase in Elk-1 signalling is required for hypoxia-induced 15-LO expression in PAFs.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Arteria Pulmonar
/
Araquidonato 15-Lipooxigenasa
/
Proteína Elk-1 con Dominio ets
/
Fibroblastos
/
Hipertensión Pulmonar
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Acta Physiol (Oxf)
Asunto de la revista:
FISIOLOGIA
Año:
2016
Tipo del documento:
Article
País de afiliación:
China