title: Inflammatory conditions increase expression of protease-activated receptor-2 by human airway smooth muscle cells in culture.
abstract: The protease-activated receptor-2 (PAR-2) has been implicated in airway inflammation and bronchial hyperresponsiveness. We wondered whether inflammatory conditions may upregulate PAR-2 expression by the human airway smooth muscle. To do so, we treated human airway smooth muscle cells (HASMC) in primary culture with interleukin-1beta (IL-1beta), a pro-inflammatory and asthma-associated cytokine. Cells were starved for 24 h and incubated with or without IL-1beta. Online fluorescent polymerase chain reaction after reverse transcription quantified PAR-2 mRNA, and Western blotting measured PAR-2 protein expression. PAR-2 was constitutively expressed by HASMC in primary culture, and IL-1beta (10 U/mL) time dependently elevated PAR-2 mRNA with a maximum of 4.7-fold after 1.5 h (P < 0.01), and PAR-2 protein expression with a maximum of 1.5-fold after 24 h (P < 0.01). The concentration dependence of the IL-1beta effect (0.1-30 U/mL) confirmed a maximal increase of PAR-2 expression at 10 U/mL. Our study clearly shows that IL-1beta upregulates PAR-2 mRNA and protein expression by HASMC in culture. This increased expression of PAR-2 in inflammatory conditions may have functional consequences in the bronchial dysfunction of asthmatic airways.
authors.affiliation: EA 3771 Inflammation and Environment in Asthma, Faculté de Pharmacie, Université Louis Pasteur-Strasbourg I, Illkirch, France. cfreund@pharma.u-strasbg.fr
authors.forename: Véronique
authors.initials: V
authors.lastname: Freund-Michel
authors.forename: Nelly
authors.initials: N
authors.lastname: Frossard
mesh_terms: D001249:Asthma / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005453:Fluorescence; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D053583:Interleukin-1beta / Q000378:metabolism* / Q000494:pharmacology; D009130:Muscle, Smooth / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D044464:Receptor, PAR-2 / Q000096:biosynthesis* / Q000235:genetics; D012137:Respiratory System / Q000187:drug effects / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D015415:Biomarkers; D053583:Interleukin-1beta; D012333:RNA, Messenger; D044464:Receptor, PAR-2