Abstract
Pulmonary fibrosis (PF) is a chronic lung disease characterized by excess extracellular matrix deposition and prolonged inflammation that fails to resolve and is druggable. Using resolvins and their precursors for inflammation resolution, we demonstrate a nano-enabled approach for accomplishing robust antifibrotic effects in bleomycin- or engineered nanomaterial-induced mouse and rat PF models. Targeting the lipid peroxidation-triggered NLRP3 inflammasome and NF-κB pathway in macrophages and the ROS-mediated TGF-β/Smad and S1P signaling in epithelial cells results in these potent protective effects at the ng/mL dosimetry. We further develop an inhalable biocompatible nanoparticle that encapsulates fish oil, a chosen resolvin precursor, with phosphatidylcholine and polyethylene glycol to enhance drug permeability and facilitate crossing the mucosal barrier, forming "fish-oilsome" (FOS). Oropharyngeal aspiration and inhalation of FOS improved the anti-inflammatory status, histological characteristics, and pulmonary function in fibrotic lungs, which was mechanistically supported by transcriptomic and proteomic analyses. Further, scale-up engineered FOS samples with the desired physicochemical properties, anti-PF efficacy, and in vivo biocompatibility were validated in different batch sizes (up to 0.2 L/batch). This study provides a practical and translatable approach to promoting inflammation resolution and PF treatment.