Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: " Cigarette smoke and lipopolysaccharide induce a proliferative airway smooth muscle phenotype. | Pera et al. Respiratory Research 2010 11 48 http content 11 1 48 RESPIRATORY RESEARCH RESEARCH Open Access Cigarette smoke and lipopolysaccharide induce a proliferative airway smooth muscle phenotype Tonio Pera 1 Reinoud Gosens1 Andries H Lesterhuis1 Riham Sami1 Marco van derToorn2 Johan Zaagsma1 and Herman Meurs1 Abstract Background A major feature of chronic obstructive pulmonary disease COPD is airway remodelling which includes an increased airway smooth muscle ASM mass. The mechanisms underlying ASM remodelling in COPD are currently unknown. We hypothesized that cigarette smoke CS and or lipopolysaccharide LPS a major constituent of CS organic dust and gram-negative bacteria that may be involved in recurrent airway infections and exacerbations in COPD patients would induce phenotype changes of ASM. Methods To this aim using cultured bovine tracheal smooth muscle BTSM cells and tissue we investigated the direct effects of CS extract CSE and LPS on ASM proliferation and contractility. Results Both CSE and LPS induced a profound and concentration-dependent increase in DNA synthesis in BTSM cells. CSE and LPS also induced a significant increase in BTSM cell number which was associated with increased cyclin D1 expression and dependent on activation of ERK 1 2 and p38 MAP kinase. Consistent with a shift to a more proliferative phenotype prolonged treatment of BTSM strips with CSE or LPS significantly decreased maximal methacholine- and KCl-induced contraction. Conclusions Direct exposure of ASM to CSE or LPS causes the induction of a proliferative hypocontractile ASM phenotype which may be involved in airway remodelling in COPD. Background Chronic obstructive pulmonary disease COPD is an inflammatory lung disease characterized by a progressive and largely irreversible airflow obstruction which involves structural changes of the lung including emphysema and small airway remodelling 1 . Small airway remodelling in COPD is characterized by .
