title: [A study of the metabolic pathways of vitamin A in the fetal human lung].
abstract: BACKGROUND
  Retinoic acid plays an essential role in lung development and is involved in all stages of embryogenesis and morphogenesis. We aimed to determine whether the human foetal lung is able to synthesize retinoic acid.
  
  
  METHODS
  ADH3, RALDH1 and CYP26B1 RNA were studied by qualitative and semi-quantitative RT-PCR in human lungs at different stages of development. In human alveolar epithelial cells (lines A549), RAR beta (induced by retinoic acid) was quantified, after treatment by retinol, by q-PCR at 24h and 48 h.
  
  
  RESULTS
  The expression of the RNA of ADH3, RALDH1 and CYP26B1 was detected for each of the four stages studied and in the A549 cell line. Only the level of RALDH1 RNA changed during the course of lung development. In the A549 cell line, treatment by retinol induced transcription of the RAR beta gene at 24 and 48 hours.
  
  
  CONCLUSIONS
  The presence of ADH3, RALDH1 and CYP26B1 during the four stages of normal lung development and in the A549 cell line, as well as the capacity to convert retinol to retinoic acid in these cells, indicate that foetal human lung has the ability to regulate the supply of vitamin A from the pseudoglandular stage.
authors.affiliation: GRED-CNRS UMR6247, INSERM U931, Clermont université, Clermont-Ferrand, France. kcoste@chu-clermontferrand.fr
authors.forename: K
authors.initials: K
authors.lastname: Coste
authors.forename: A
authors.initials: A
authors.lastname: Labbe
mesh_terms: D000426:Alcohol Dehydrogenase / Q000378:metabolism*; D000444:Aldehyde Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D000080924:Aldehyde Dehydrogenase 1 Family; D015415:Biomarkers / Q000378:metabolism; D002478:Cells, Cultured; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism*; D005333:Fetus; D006801:Humans; D066298:In Vitro Techniques; D008168:Lung / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D011650:Pulmonary Alveoli / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000235:genetics / Q000378:metabolism; D050697:Retinal Dehydrogenase; D000072516:Retinoic Acid 4-Hydroxylase; D012177:Retinol-Binding Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014212:Tretinoin / Q000378:metabolism; D014801:Vitamin A / Q000378:metabolism*; D014815:Vitamins / Q000378:metabolism
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D012177:Retinol-Binding Proteins; D014815:Vitamins; C082925:retinoic acid receptor beta; D014801:Vitamin A; D014212:Tretinoin; D003577:Cytochrome P-450 Enzyme System; C420272:ADH1C protein, human; D000426:Alcohol Dehydrogenase; C000607079:CYP26B1 protein, human; D000072516:Retinoic Acid 4-Hydroxylase; D000080924:Aldehyde Dehydrogenase 1 Family; D000444:Aldehyde Dehydrogenase; C510223:ALDH1A1 protein, human; D050697:Retinal Dehydrogenase