Induction of heme oxygenase-1, biliverdin reductase and H-ferritin in lung macrophage in smokers with primary spontaneous pneumothorax: role of HIF-1alpha.
BACKGROUND
Few data concern the pathophysiology of primary spontaneous pneumothorax (PSP), which is associated with alveolar hypoxia/reoxygenation. This study tested the hypothesis that PSP is associated with oxidative stress in lung macrophages. We analysed expression of the oxidative stress marker 4-HNE; the antioxidant and anti-inflammatory proteins heme oxygenase-1 (HO-1), biliverdin reductase (BVR) and heavy chain of ferritin (H-ferritin); and the transcription factors controlling their expression Nrf2 and HIF-1alpha, in lung samples from smoker and nonsmoker patients with PSP (PSP-S and PSP-NS), cigarette smoke being a risk factor of recurrence of the disease.


RESULTS
mRNA was assessed by RT-PCR and proteins by western blot, immunohistochemistry and confocal laser analysis. 4-HNE, HO-1, BVR and H-ferritin were increased in macrophages from PSP-S as compared to PSP-NS and controls (C). HO-1 increase was associated with increased expression of HIF-1alpha mRNA and protein in alveolar macrophages in PSP-S patients, whereas Nrf2 was not modified. To understand the regulation of HO-1, BVR and H-ferritin, THP-1 macrophages were exposed to conditions mimicking conditions in C, PSP-S and PSP-NS patients: cigarette smoke condensate (CS) or air exposure followed or not by hypoxia/reoxygenation. Silencing RNA experiments confirmed that HIF-1alpha nuclear translocation was responsible for HO-1, BVR and H-ferritin induction mediated by CS and hypoxia/reoxygenation.


CONCLUSIONS
PSP in smokers is associated with lung macrophage oxidative stress. The response to this condition involves HIF-1alpha-mediated induction of HO-1, BVR and H-ferritin.
Inserm, U700, Faculté de Médecine-Site Bichat, Université Denis Diderot-Paris 7, Paris, France.
Delphine
D
Goven
Anne
A
Boutten
Véronique
V
Leçon-Malas
Joëlle
J
Marchal-Sommé
Paul
P
Soler
Jorge
J
Boczkowski
Marcel
M
Bonay
D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D001052:Apoferritins / Q000235:genetics / Q000378:metabolism*; D001706:Biopsy; D001798:Blood Proteins / Q000235:genetics / Q000378:metabolism; D015687:Cell Hypoxia; D002460:Cell Line; D004790:Enzyme Induction; D047093:Eosinophil Major Basic Protein; D005786:Gene Expression Regulation; D020868:Gene Silencing; D051547:Heme Oxygenase-1 / Q000096:biosynthesis*; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D008168:Lung / Q000473:pathology; D008264:Macrophages / Q000201:enzymology* / Q000473:pathology; D051267:NF-E2-Related Factor 2 / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D011030:Pneumothorax / Q000201:enzymology* / Q000473:pathology; D011509:Proteoglycans / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D012907:Smoking / Q000378:metabolism*; D000097382:CD68 Molecule
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D001052:Apoferritins; D001798:Blood Proteins; D047093:Eosinophil Major Basic Protein; D051547:Heme Oxygenase-1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D051267:NF-E2-Related Factor 2; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010100:Oxygen; D011509:Proteoglycans; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C067980:CD68 antigen, human; D000097382:CD68 Molecule; C074129:PRG2 protein, human; C019789:biliverdin reductase