Background
Airway remodeling is implicated in the pathogenesis of asthma, and abnormal proliferation of airway smooth muscle cells (ASMCs) contribute to airway remodeling. Inflammatory mediator, transforming growth factor-β1 (TGF-β1), stimulates the proliferation of ASMCs, and is associated with airway remodeling in asthma. Dexmedetomidine (DEX) has been widely used in the adjuvant therapy of acute asthma.
Conclusion
DEX suppressed TGF-β1-induced ECM production and proliferation of ASMCs through inactivation of p38 mitogen-activated protein kinase (MAPK) pathway, providing a potential strategy for prevention of asthma.
Material and methods
Human ASMCs were incubated with TGF-β1 for 48 hours, and then treated with different concentrations of DEX for another 24 hours. Cell proliferation was detected by MTT and BrdU (5'-bromo-2'-deoxyuridine) staining. Flow cytometry was used to assess cell apoptosis, and western blot was applied to identify the underlying mechanism.
Methods
Human ASMCs were incubated with TGF-β1 for 48 hours, and then treated with different concentrations of DEX for another 24 hours. Cell proliferation was detected by MTT and BrdU (5'-bromo-2'-deoxyuridine) staining. Flow cytometry was used to assess cell apoptosis, and western blot was applied to identify the underlying mechanism.
Objective
The potential effects of DEX on extracellular matrix (ECM) production and proliferation of ASMCs were investigated in this study. Material and
Results
TGF-β1 induced increase in cell viability and bromodeoxyuridine (BrdU) positive cells in ASMCs while repressed cell apoptosis. Second, TGF-β1-induced ASMCs were then treated with different concentrations of DEX. Cell viability of TGF-β1-induced ASMCs was decreased by incubation of DEX. The number of BrdU positive cells in TGF-β1-induced ASMCs was reduced by incubation of DEX. Moreover, incubation of DEX promoted cell apoptosis of TGF-β1-induced ASMCs. Third, incubation of DEX attenuated TGF-β1-induced increase in fibronectin, collagen I, MMP9, and versican in ASMCs. Lastly, the up-regulation of phosphorylated extracellular receptor kinase (p-ERK), phosphorylated Jun N-terminal Kinase (p-JNK), and p-p38 in TGF-β1-induced ASMCs was reversed by incubation of DEX.