The leukotriene receptor antagonist pranlukast attenuates airway remodeling by suppressing TGF-β signaling

Abstract

Background/objective: Asthma is a chronic airway disease characterized by airway eosinophilic inflammation and remodeling, which are associated with a loss in lung function. Although both contribute significantly to asthma pathogenesis, mechanistic studies and drug discovery have focused on inflammatory targets. In this study, we investigated the effect of the leukotriene receptor antagonist pranlukast on allergic airway inflammation and remodeling in vivo and in vitro.

Method: Four groups of female BALB/c mice (control; ovalbumin [OVA]-sensitized and -challenged; dimethyl sulfoxide [DMSO]-treated OVA; and pranlukast-treated OVA) were examined. Lung pathology, cytokine production, and airway hyperresponsiveness (AHR) measurements were compared among these groups. A human fetal lung fibroblast HFL-1 cell line was used in the peribranchial fibrosis analysis.

Results: OVA-sensitized and -challenged mice exhibited allergic airway inflammation and significant increases in Th2 cytokines. Pranlukast-treated mice showed significant attenuation of allergic airway inflammation. The pranlukast treatment decreased AHR and attenuated airway remodeling to goblet cell hyperplasia, collagen deposition, α-smooth muscle actin expression, and pro-fibrotic gene expression. We further demonstrated that pranlukast not only inhibited transforming growth factor-beta 1 (TGF-β1)-induced Smad signaling in human fetal lung fibroblast cells but also simultaneously reduced collagen synthesis and pro-fibrotic gene expression.

Conclusions: The leukotriene receptor antagonist pranlukast can reduce airway inflammation and remodeling by inhibiting TGF-β/Smad signaling in an OVA-sensitized and -challenged asthma mouse model, thus suppressing AHR.

Keywords: Animal model; Asthma; LTRA; Remodeling; TGF-β signaling.