The miR-3164/PAD4 axis regulates NETosis to prevent airway inflammation and remodeling through the TLR2/NF-κB signaling pathway

Background: Alleviating airway inflammation and reversing airway remodeling are critical therapeutic objectives in asthma treatment. This study aimed to investigate the role of miR-3164 in regulating PAD4-mediated NETosis and to elucidate the underlying mechanisms through which it attenuates airway inflammation and reverses remodeling.

Methods: The effects of miR-3164 on PAD4 expression and neutrophil extracellular trap (NET) formation were evaluated via dual-luciferase reporter assays, Western blotting, quantitative Real-Time PCR (qRT‒PCR), and flow cytometry. The influence of neutrophils treated with miR-3164 mimics on the proliferation and migration of mouse airway smooth muscle cells (ASMCs) was assessed via MTT and Transwell assays.

Results: The dual-luciferase reporter assay confirmed a targeting relationship between miR-3164 and PAD4. Treatment with miR-3164 mimics suppressed PAD4 expression in neutrophils and significantly altered the levels of myeloperoxidase (MPO) and neutrophil Elastase (NE) within NETs. These effects confer the ability of miR-3164 mimics to markedly downregulate the expression of inflammation- and airway remodeling-related biomarkers, including TLR2, IκBα, NF-κB, calponin, α-SMA, and E-cadherin, in airway smooth muscle cells (ASMCs). Furthermore, NETs treated with miR-3164 mimics significantly attenuated the viability and migration capacity of ASMCs exposed to LPS and ATP.

Conclusions: Our findings demonstrate that modulating NETosis represents a potential therapeutic strategy to attenuate airway inflammatory responses and remodeling via the TLR2/NF-κB signaling pathway, thereby offering a novel target for the treatment of asthma.

Clinical trial number: Not applicable.

Airway inflammation; Asthma; NETosis; Neutrophils; PAD4; miR-3164.