Phosphodiesterase (PDE) 7 in inflammatory cells from patients with asthma and COPD

• Published in: Pulmonary pharmacology & therapeutics Vol. 20; no. 1; pp. 60 - 68
• Main Authors: Jones, N.A, Leport, M, Holand, T, Vos, T, Morgan, M, Fink, M, Pruniaux, M.-P, Berthelier, C, O’Connor, B.J, Bertrand, C, Page, C.P
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-01-2007
• Subjects: 3',5'-Cyclic-AMP Phosphodiesterases - antagonists & inhibitors; 3',5'-Cyclic-AMP Phosphodiesterases - genetics; 3',5'-Cyclic-AMP Phosphodiesterases - metabolism; Adult; Aged; Asthma; Asthma - blood; Benzamides - pharmacology; CD4-Positive T-Lymphocytes - cytology; CD4-Positive T-Lymphocytes - drug effects; CD4-Positive T-Lymphocytes - metabolism; CD8-Positive T-Lymphocytes - cytology; CD8-Positive T-Lymphocytes - drug effects; CD8-Positive T-Lymphocytes - metabolism; Cell Proliferation - drug effects; COPD; Cyclic Nucleotide Phosphodiesterases, Type 4; Cyclic Nucleotide Phosphodiesterases, Type 7; Dose-Response Relationship, Drug; Female; Humans; Leukocyte Elastase - genetics; Leukocyte Elastase - metabolism; Leukocytes - cytology; Leukocytes - drug effects; Leukocytes - metabolism; Lymphocyte; Male; Medical Education; Middle Aged; N-Formylmethionine Leucyl-Phenylalanine - pharmacology; Neutrophil; Neutrophils - cytology; Neutrophils - drug effects; Neutrophils - metabolism; PDE 4; PDE 7; Phosphodiesterase; Phosphodiesterase Inhibitors - pharmacology; Phytohemagglutinins - pharmacology; Pulmonary Disease, Chronic Obstructive - blood; Pulmonary/Respiratory; RNA, Messenger - genetics; RNA, Messenger - metabolism; Rolipram - pharmacology; Thiadiazoles - pharmacology; RNA; DMSO; cluster of differentiation; 6-carboxy-tetramethyl-rhodamine; phosphate-buffered saline; HTAB; TAMRA; ethylenediaminetetraacetic acid; magnetic antibody cell sorting; threshold cycle; messenger ribonucleic acid; cDNA; PBS; T m; cpm; R n; PDE 4; counts per minute; MACS; HPBMNC; PDE 7; Asthma; neutrophil elastase; NE; PCR; 6-carboxy-fluorescein; ribonucleic acid; reporter dye fluorescence; complementary deoxyribonucleic acid; PHA; mRNA; cAMP; PDE; dimethyl sulphoxide; hexadecyltrimethylammonium bromide; melting temperature; C t; polymerase chain reaction; Phosphodiesterase; CD; g; EDTA; PMN; phytohaemagluttinin; FAM; cyclic adenosine monophosphate; Neutrophil; HBSS; centrifugal gravity; polymorphonuclear neutrophil; Lymphocyte; Hank's balanced salts solution; COPD; chronic obstructive pulmonary disease; human peripheral blood mixed mononuclear cells
• ISSN: 1094-5539; 1522-9629
• DOI: 10.1016/j.pupt.2005.11.010

Abstract In inflammatory cells, the low Km cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase (PDE) 4 subtype is predominant in terms of expression and function, although more recently it has been suggested that PDE 7 may also play a role in regulating inflammatory cell activity. In the present study, PDE 4 and PDE 7 subtype messenger ribonucleic acid (mRNA) transcripts in CD4 and CD8 lymphocytes from healthy ( n = 1 0 ) and asthmatic ( n = 1 0 ) subjects and polymorphonuclear neutrophils (PMNs) and CD8 lymphocytes obtained from healthy ( n = 1 0 ) and chronic obstructive pulmonary disease (COPD) ( n = 7 ) subjects were identified and quantified. PDE 4A, PDE 4B, PDE 4D and PDE 7A mRNA were present in similar quantities in both CD4 and CD8 lymphocytes obtained from healthy and asthmatic subjects and in CD8 lymphocytes obtained from healthy and COPD subjects. Expression of PDE 4C and PDE 7B mRNA was also observed, although transcript levels were low and variable between individuals. In addition, the effects of selective PDE 7 inhibition on both phytohaemagluttinin (PHA)-induced human peripheral blood mixed mononuclear cell (HPBMNC) proliferation and fMLP-induced neutrophil elastase (NE) release were studied. HPBMNC and human neutrophils, isolated from the venous blood of healthy volunteers ( n = 6 ) were treated with either a novel selective PDE 7 inhibitor PF 0332040 alone or in combination with rolipram. Proliferation of HPBMNC was stimulated by PHA (2 μg ml−1 ) and assessed by [3 H]-thymidine incorporation, while fMLP-induced (100 nM) NE release was determined using a chromogenic substrate. Both rolipram (0.003–10 μM) and PF 0332040 (0.003–10 μM) significantly inhibited PHA-stimulated proliferation of HPBMNC ( * * P < 0.0 1 ). Co-administration of rolipram (0.3–10 μM) and PF 0332040 (0.003–10 μM) significantly increased the degree of inhibition observed, compared to when either drug was administered alone ( * * P < 0.0 1 ). PF 0332040 (0.003–10 μM) had no inhibitory effect on NE release from human peripheral blood neutrophils stimulated with fMLP (100 nM), while rolipram (0.003–10 μM) significantly inhibited neutrophil degranulation ( * * P < 0.0 1 ). These findings suggest no evidence of altered PDE 4 or PDE 7 mRNA transcript levels in inflammatory cells isolated from the peripheral venous blood of mild asymptomatic asthmatic subjects or stable COPD subjects, however, inhibition of PDE 7 may influence mononuclear cell function.