title: Involvement of MMP-12 and phosphodiesterase type 4 in cigarette smoke-induced inflammation in mice.
abstract: The aim of the present study was to characterise a mouse model of airways inflammation induced by cigarette smoke and to compare it with a lipopolysaccharide (LPS) model with regards to the efficacy of a PDE4 inhibitor (cilomilast), a corticosteroid (dexamethasone) and macrophage metalloelastase (MMP)-12 gene deletion. Cigarette smoke exposure for 3 days induced a time-dependent airway neutrophilia associated with an increased level of keratinocyte-derived chemokine (KC), macrophage inflammatory protein (MIP)-2, MIP-1alpha and MMP-9 in the bronchoalveolar lavage (BAL). LPS exposure also induced an increase in the number of neutrophils in BAL. Studies in MMP-12-/- mice showed that in contrast to the smoking model, MMP-12 did not have a critical role in LPS-induced inflammation. Both cilomilast and dexamethasone blocked LPS-induced neutrophilia in a dose-dependent manner. Cilomilast inhibited cigarette smoke-induced neutrophilia and MIP-1alpha, but only 10 mg.kg(-1) of dexamethasone was effective. Both anti-inflammatory treatments had no effect on the levels of KC and MIP-2 in the BAL. Although the inflammatory response was very similar in the smoking model and LPS, the pharmacological modulation and the MMP-12 gene deletion highlighted the differences in the mechanisms involved. Furthermore, the cigarette smoke model seemed to better represent the situation described in chronic obstructive pulmonary disease patients. In conclusion, these differences underline the importance of using an acute smoke-exposure model to investigate potential new treatments for chronic obstructive pulmonary disease.
authors.affiliation: INSERM U620, Université de Rennes 1, 2, avenue du Professeur Léon Bernard, 35043 Rennes cedex, France. vincent.lagente@univ-rennes1.fr
authors.forename: O
authors.initials: O
authors.lastname: Leclerc
authors.forename: V
authors.initials: V
authors.lastname: Lagente
authors.forename: J-M
authors.initials: JM
authors.lastname: Planquois
authors.forename: C
authors.initials: C
authors.lastname: Berthelier
authors.forename: M
authors.initials: M
authors.lastname: Artola
authors.forename: T
authors.initials: T
authors.lastname: Eichholtz
authors.forename: C P
authors.initials: CP
authors.lastname: Bertrand
authors.forename: F
authors.initials: F
authors.lastname: Schmidlin
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors / Q000502:physiology*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D002264:Carboxylic Acids / Q000494:pharmacology; D002872:Chromosome Deletion; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D003509:Cyclohexanecarboxylic Acids; D003907:Dexamethasone / Q000494:pharmacology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D008297:Male; D053508:Matrix Metalloproteinase 12; D008666:Metalloendopeptidases / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology; D009570:Nitriles / Q000494:pharmacology; D011014:Pneumonia / Q000276:immunology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000276:immunology*; D012907:Smoking / Q000009:adverse effects* / Q000276:immunology
chemical_list: D002264:Carboxylic Acids; D003509:Cyclohexanecarboxylic Acids; D009570:Nitriles; D003907:Dexamethasone; C433247:Cilomilast; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D008666:Metalloendopeptidases; D053508:Matrix Metalloproteinase 12