Cigarette smoke enhances proliferation and extracellular matrix deposition by human fetal airway smooth muscle

Abstract

Cigarette smoke is a common environmental insult associated with increased risk of developing airway diseases such as wheezing and asthma in neonates and children. In adults, asthma involves airway remodeling characterized by increased airway smooth muscle (ASM) cell proliferation and increased extracellular matrix (ECM) deposition, as well as airway hyperreactivity. The effects of cigarette smoke on remodeling and contractility in the developing airway are not well-elucidated. In this study, we used canalicular-stage (18-20 wk gestational age) human fetal airway smooth muscle (fASM) cells as an in vitro model of the immature airway. fASM cells were exposed to cigarette smoke extract (CSE; 0.5-1.5% for 24-72 h), and cell proliferation, ECM deposition, and intracellular calcium ([Ca(2+)]i) responses to agonist (histamine 10 μM) were used to evaluate effects on remodeling and hyperreactivity. CSE significantly increased cell proliferation and deposition of ECM molecules collagen I, collagen III, and fibronectin. In contrast, [Ca(2+)]i responses were not significantly affected by CSE. Analysis of key signaling pathways demonstrated significant increase in extracellular signal-related kinase (ERK) and p38 activation with CSE. Inhibition of ERK or p38 signaling prevented CSE-mediated changes in proliferation, whereas only ERK inhibition attenuated the CSE-mediated increase in ECM deposition. Overall, these results demonstrate that cigarette smoke may enhance remodeling in developing human ASM through hyperplasia and ECM production, thus contributing to development of neonatal and pediatric airway disease.

Alcohol and Cigarette Smoke Components Activate Human Pancreatic Stellate Cells: Implications for the Progression of Chronic Pancreatitis

“…In our study, collagen type I expression was significantly induced by NNK, alone and in combination with EtOH, but not by CSE or nicotine. The lack of an effect on collagen I expression in response to CSE and nicotine was unexpected and is at variance with previous studies reporting nicotine-induced increase in collagen I-a2 mRNA levels in HSCs (Soeda et al, 2012) and CSE-induced increased collagen I secretion by human fetal airway smooth muscle cells (Vogel et al, 2014). However, the observed effects of NNK + EtOH on collagen I expression in PSCs would support the concept that cigarette smoking may enhance fibrogenesis within the pancreas via this metabolite, thereby promoting increased pancreatic injury during alcoholic pancreatitis.…”

Brain-derived neurotrophic factor and airway fibrosis in asthma

“…BDNF AND AIRWAY FIBROSIS firmed visually, ensuring that only ECM remained. ECM deposition was then measured using a semiquantitative immunofluorescence Li-Cor In-Cell Western technique for collagen-1 (ab34710), collagen-3 (ab7778), and fibronectin (sc-9068) (58). ECM intensity was normalized to cell number via MTS assay (Promega, Madison, WI) before cell removal.…”

Phenylpyrrolidine structural mimics of pirfenidone lacking antifibrotic activity: A new tool for mechanism of action studies

“…Adapting from previously published methods (Jones et al, 2010; Vogel et al, 2014), lung fibroblasts were plated to confluence in clear-bottom 96-well plates in EMEM containing 10% FBS and allowed to attach for 6 h. Media was then exchanged with EMEM containing 0.1% FBS plus the indicated compound concentration. All wells were treated with a final concentration of 0.5% DMSO.…”