Decreased neprilysin and pulmonary vascular remodeling in chronic obstructive pulmonary disease.

RATIONALE Studies with genetically engineered mice showed that decreased expression of the transmembrane peptidase neprilysin (NEP) increases susceptibility to hypoxic pulmonary vascular remodeling and hypertension; in hypoxic wild-type mice, expression is decreased early in distal pulmonary arteries, where prominent vascular remodeling occurs. Therefore, in humans with smoke- and hypoxia-induced vascular remodeling, as in chronic obstructive pulmonary disease (COPD), pulmonary activity/expression of NEP may likewise be decreased. OBJECTIVES To test whether NEP activity and expression are reduced in COPD lungs and pulmonary arterial smooth muscle cells (SMCs) exposed to cigarette smoke extract or hypoxia and begin to investigate mechanisms involved. METHODS Control and advanced COPD lung lysates (n = 13-14) were analyzed for NEP activity and protein and mRNA expression. As a control, dipeptidyl peptidase IV activity was analyzed. Lung sections were assessed for vascular remodeling and oxidant damage. Human pulmonary arterial SMCs were exposed to cigarette smoke extract, hypoxia, or H₂O₂, and incubated with antioxidants or lysosomal/proteasomal inhibitors. MEASUREMENTS AND MAIN RESULTS COPD lungs demonstrated areas of vascular rarification, distal muscularization, and variable intimal and prominent medial/adventitial thickening. NEP activity was reduced by 76%; NEP protein expression was decreased in alveolar walls and distal vessels; mRNA expression was also decreased. In SMCs exposed to cigarette smoke extract, hypoxia, and H₂O₂, NEP activity and expression were also reduced. Reactive oxygen species inactivated NEP activity; NEP protein degradation appeared to be substantially induced. CONCLUSIONS Mechanisms responsible for reduced NEP activity and protein expression include oxidative reactions and protein degradation. Maintaining or increasing lung NEP may protect against pulmonary vascular remodeling in response to chronic smoke and hypoxia.

[1]  B. Housset,et al.  Role for interleukin-6 in COPD-related pulmonary hypertension. , 2009, Chest.

[2]  H. Mal,et al.  Pulmonary hemodynamics in advanced COPD candidates for lung volume reduction surgery or lung transplantation. , 2005, Chest.

[3]  R. Channick,et al.  Endothelin antagonism in pulmonary arterial hypertension. , 2005, Seminars in respiratory and critical care medicine.

[4]  C. White,et al.  Superoxide dismutase and catalase conjugated to polyethylene glycol increases endothelial enzyme activity and oxidant resistance. , 1988, The Journal of biological chemistry.

[5]  F. Taiwo.  Mechanism of tiron as scavenger of superoxide ions and free electrons , 2008 .

[6]  M. Frid,et al.  Unique growth properties of neonatal pulmonary vascular cells: importance of time- and site-specific responses, cell-cell interaction, and synergy. , 1996, Journal of perinatology : official journal of the California Perinatal Association.

[7]  M. Raizada,et al.  Evidence for angiotensin-converting enzyme 2 as a therapeutic target for the prevention of pulmonary hypertension. , 2009, American journal of respiratory and critical care medicine.

[8]  J. Nadel,et al.  Cigarette smoke induces bronchoconstrictor hyperresponsiveness to substance P and inactivates airway neutral endopeptidase in the guinea pig. Possible role of free radicals. , 1989, The Journal of clinical investigation.

[9]  I. Preston.  Clinical perspective of hypoxia-mediated pulmonary hypertension. , 2007, Antioxidants & redox signaling.

[10]  O. Finco,et al.  Neutral Endopeptidase Modulates Septic Shock a , 1996, Annals of the New York Academy of Sciences.

[11]  I. De Meester,et al.  CD26/dipeptidylpeptidase IV-targeted therapy of acute lung rejection in rats. , 2006, The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation.

[12]  M. Hersberger,et al.  Genetic Polymorphisms of the Serotonin Transporter, but Not the 2a Receptor or Nitric Oxide Synthetase, Are Associated with Pulmonary Hypertension in Chronic Obstructive Pulmonary Disease , 2009, Respiration.

[13]  D. Payan,et al.  The control of microvascular permeability and blood pressure by neutral endopeptidase , 1997, Nature Medicine.

[14]  J. Crapo,et al.  Manganic porphyrins possess catalase activity and protect endothelial cells against hydrogen peroxide-mediated injury. , 1997, Archives of biochemistry and biophysics.

[15]  Rolf Mentlein,et al.  Dipeptidyl-peptidase IV (CD26)-role in the inactivation of regulatory peptides , 1999, Regulatory Peptides.

[16]  A. Chaouat,et al.  Pulmonary Hypertension in Chronic Obstructive Pulmonary Disease and Interstitial Lung Diseases , 2009, Seminars in respiratory and critical care medicine.

[17]  R. Mentlein.  Cell-Surface Peptidases , 2004, International Review of Cytology.

[18]  N. Voelkel,et al.  Oxidative stress in severe pulmonary hypertension. , 2004, American journal of respiratory and critical care medicine.

[19]  L. Hersh,et al.  Susceptibility of amyloid beta peptide degrading enzymes to oxidative damage: a potential Alzheimer's disease spiral. , 2005, Biochemistry.

[20]  M. Wick,et al.  Divergent contractile and structural responses of the murine PKC-epsilon null pulmonary circulation to chronic hypoxia. , 2005, American journal of physiology. Lung cellular and molecular physiology.

[21]  R. Panos,et al.  Pulmonary hypertension associated with COPD , 2008, International journal of chronic obstructive pulmonary disease.

[22]  A. R. Hulsmann,et al.  Peptidases: structure, function and modulation of peptide‐mediated effects in the human lung , 1999, Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology.

[23]  M. Steiner.  World Health Organization Class III COPD-associated pulmonary hypertension: are we there yet in understanding the pathobiology of the disease? , 2009, Chest.

[24]  S. Said.  Mediators and modulators of pulmonary arterial hypertension. , 2006, American journal of physiology. Lung cellular and molecular physiology.

[25]  N. Morrell.  Role of bone morphogenetic protein receptors in the development of pulmonary arterial hypertension. , 2010, Advances in experimental medicine and biology.

[26]  M. Rabinovitch.  Molecular pathogenesis of pulmonary arterial hypertension. , 2008, The Journal of clinical investigation.

[27]  L. Dick,et al.  Mechanistic Studies on the Inactivation of the Proteasome by Lactacystin , 1996, The Journal of Biological Chemistry.

[28]  H. Wieczorek,et al.  Inhibitors of V-ATPases: old and new players , 2009, Journal of Experimental Biology.

[29]  So Ri Kim,et al.  Impact of oxidative stress on lung diseases , 2009, Respirology.

[30]  William A. Pryor,et al.  The Tar Radical ( s ) in Cigarette Smoke : ESR Studies , 2006 .

[31]  Darrell R. Abernethy,et al.  International Union of Pharmacology: Approaches to the Nomenclature of Voltage-Gated Ion Channels , 2003, Pharmacological Reviews.

[32]  D. Butterfield,et al.  Detection of 4-hydroxy-2-nonenal- and 3-nitrotyrosine-modified proteins using a proteomics approach. , 2009, Methods in molecular biology.

[33]  Y. Miller,et al.  Neprilysin Regulates PASMC Phenotype And PDGFR Signaling In Mice , 2010, ATS 2010.

[34]  E. Dempsey,et al.  Protein kinase C activation allows pulmonary artery smooth muscle cells to proliferate to hypoxia. , 1991, The American journal of physiology.

[35]  D. Nanus,et al.  Involvement of neutral endopeptidase in neoplastic progression. , 2005, Biochimica et biophysica acta.

[36]  Shing M. Lee,et al.  Hemodynamic characterization of patients with severe emphysema. , 2002, American journal of respiratory and critical care medicine.

[37]  C. Durinx,et al.  Kinetic study of the processing by dipeptidyl‐peptidase IV/CD26 of neuropeptides involved in pancreatic insulin secretion , 2001, FEBS letters.

[38]  Y. Miller,et al.  Neutral endopeptidase: variable expression in human lung, inactivation in lung cancer, and modulation of peptide-induced calcium flux. , 1996, Cancer research.

[39]  D. Nanus,et al.  Is methylation the key to CD10 loss? , 2010, Journal of pediatric hematology/oncology.

[40]  E. Dempsey,et al.  Divergent Contractile and Structural Responses of the Murine Protein Kinase C-ε Null Pulmonary Circulation to Chronic Hypoxia , 2005 .

[41]  P. Jeffery.  Remodeling in asthma and chronic obstructive lung disease. , 2001, American journal of respiratory and critical care medicine.

[42]  M. Shipp,et al.  CD10/neutral endopeptidase 24.11 in developing human fetal lung. Patterns of expression and modulation of peptide-mediated proliferation. , 1992, The Journal of clinical investigation.

[43]  T. Honda,et al.  Pulmonary artery remodeling modifies pulmonary hypertension during exercise in severe emphysema. , 2000, Respiration physiology.

[44]  Raúl San José Estépar,et al.  Pulmonary hypertension and computed tomography measurement of small pulmonary vessels in severe emphysema. , 2010, American journal of respiratory and critical care medicine.

[45]  S. Colgan,et al.  The FASEB Journal • Research Communication HIF-dependent induction of adenosine A2B receptor in hypoxia , 2022 .

[46]  K. Brown,et al.  Fibroblast foci are not discrete sites of lung injury or repair: the fibroblast reticulum. , 2006, American journal of respiratory and critical care medicine.

[47]  V. Peinado,et al.  Pulmonary vascular involvement in COPD. , 2008, Chest.

[48]  M. Wick,et al.  Lung neprilysin activity and expression are decreased in humans with COPD and pulmonary vascular remodeling , 2009 .

[49]  M. Wick,et al.  452 DIVERGENT CONTRACTILE AND STRUCTURAL RESPONSES OF THE MURINE PKC-ε NULL PULMONARY CIRCULATION TO CHRONIC HYPOXIA. , 2001, Journal of Investigative Medicine.

[50]  R. Jensen,et al.  Mammalian Bombesin Receptors : Nomenclature , Distribution , Pharmacology , Signaling , and Functions in Normal and Disease States , 2008 .

[51]  V. Peinado,et al.  Characterization of pulmonary vascular remodelling in smokers and patients with mild COPD , 2002, European Respiratory Journal.

[52]  J. Gosney,et al.  Pulmonary neuroendocrine cell system in pediatric and adult long disease , 1997, Microscopy research and technique.

[53]  K. Stenmark,et al.  Hypoxia decreases lung neprilysin expression and increases pulmonary vascular leak. , 2001, American journal of physiology. Lung cellular and molecular physiology.

[54]  P. Robberecht,et al.  Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP-27, but not PACAP-38) degradation by the neutral endopeptidase EC 3.4.24.11. , 1997, Biochemical pharmacology.

[55]  M. Pfaffl,et al.  A new mathematical model for relative quantification in real-time RT-PCR. , 2001, Nucleic acids research.

[56]  J. Reusch,et al.  Platelet-Derived Growth Factor BB Induces Nuclear Export and Proteasomal Degradation of CREB via Phosphatidylinositol 3-Kinase/Akt Signaling in Pulmonary Artery Smooth Muscle Cells , 2006, Molecular and Cellular Biology.

[57]  I. Weiler,et al.  The use of total protein stains as loading controls: An alternative to high-abundance single-protein controls in semi-quantitative immunoblotting , 2008, Journal of Neuroscience Methods.

[58]  D. Dickson,et al.  Oxidized neprilysin in aging and Alzheimer's disease brains. , 2003, Biochemical and biophysical research communications.

[59]  L. Hersh,et al.  Neprilysin null mice develop exaggerated pulmonary vascular remodeling in response to chronic hypoxia. , 2009, The American journal of pathology.

[60]  S. Aguayo.  Determinants of susceptibility to cigarette smoke. Potential roles for neuroendocrine cells and neuropeptides in airway inflammation, airway wall remodeling, and chronic airflow obstruction. , 1994, American journal of respiratory and critical care medicine.

[61]  Deepti Malhotra,et al.  Heightened endoplasmic reticulum stress in the lungs of patients with chronic obstructive pulmonary disease: the role of Nrf2-regulated proteasomal activity. , 2009, American journal of respiratory and critical care medicine.

[62]  M. Cosio,et al.  Mechanisms of cigarette smoke-induced COPD: insights from animal models. , 2008, American journal of physiology. Lung cellular and molecular physiology.