Nano-Encapsulated Black Bean-Cultivated Cordyceps militaris Attenuates PM- and LPS-Induced Airway Inflammation

Background/Objectives: Exposure to particulate matter (PM) containing bacterial endotoxins triggers inflammation and oxidative stress in the respiratory epithelium. In this study, we investigated chitosan nanoparticle-loaded Cordyceps militaris grown on germinated Rhynchosia nulubilis (GCN) as a potential functional food-derived ingredient against PM- and lipopolysaccharide (LPS)-induced cellular damage in human lung epithelial cells. Methods: This study employed an integrative approach combining GCN analysis with bioinformatics methods using a PM- and LPS-induced pulmonary cellular inflammation model. Gene Expression Omnibus (GEO) transcriptomic datasets and Cytoscape-based network analysis were utilized to identify key hub genes and signaling pathways associated with PM- and LPS-induced pulmonary inflammation, which were subsequently validated by RT-PCR and Western blotting. Results: Nano-encapsulation significantly improved the antioxidant capacity and storage stability of the extract compared with non-encapsulated Cordyceps militaris grown on germinated Rhynchosia nulubilis (GRC). GCN markedly attenuated PM- and LPS-induced cytotoxicity and intracellular reactive oxygen species (ROS) production in a dose-dependent manner, resulting in a therapeutic index approximately 4.5-fold higher than that of GRC under PM and LPS co-exposure. Bioinformatics analysis identified inflammation-related genes and pathways associated with PM- and LPS-induced pulmonary responses, primarily enriched in tumor necrosis factor (TNF)-related inflammatory pathways, Toll-like receptor signaling, and cytokine signaling. Consistent with these findings, GCN suppressed the expression of C-X-C motif chemokine ligand 2 (CXCL-2) and tumor necrosis factor-alpha (TNF-α) mRNA and inhibited mitogen-activated protein kinase (MAPK)-mediated activator protein-1 (AP-1) and nuclear factor-kappa B (NF-κB) signaling pathways in human type II alveolar epithelial cells (A549). Conclusions: Collectively, nano-encapsulation enhanced the stability and bioactivity of Cordyceps militaris-based extracts, suggesting that GCN may have potential as a functional food-derived candidate ingredient to protect airway epithelial cells against inflammation and oxidative stress induced by PM and LPS. As this study was conducted using an in vitro A549 epithelial cell model, further validation in physiologically relevant systems is needed to confirm its translational applicability.