siHIF-1α-loaded micellar nanoparticles inhibit M1 macrophage activation to ameliorate chronic rhinosinusitis

Objective: To investigate the molecular mechanisms by which micellar nanoparticles loaded with small interfering RNA targeting hypoxia-inducible factor 1-alpha (MNP_siHIF-1α) modulate macrophage polarization and Ferroptosis in chronic rhinosinusitis (CRS), offering a novel therapeutic approach to ameliorate chronic inflammation and immune dysregulation in CRS.

Methods: Transcriptomic analysis of the GSE10406 dataset identified 3821 differentially expressed genes (DEGs) in CRS, with functional enrichment via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Single-cell RNA Sequencing (scRNA-seq) using the Seurat package characterized cellular heterogeneity in nasal mucosal tissues of CRS mice. In vitro, Raw264.7 macrophages were transfected with lentiviral sh-HIF-1α or oe-TFRC constructs, followed by RT-qPCR, chromatin immunoprecipitation (ChIP), dual-luciferase assays, and flow cytometry to assess HIF-1α-TFRC interactions, ROS accumulation, and M1 polarization. MNP_siHIF-1α, prepared using PCL-PEG/PPEEA diblock copolymers, was characterized via dynamic light scattering (DLS) and gel retardation assays. In vivo, CRS mice received intranasal MNP_siHIF-1α (10 mg/mL, 20 μL, thrice weekly for 4 weeks), with histopathological and inflammatory outcomes evaluated by H&E staining, immunohistochemistry, and ELISA.

Results: HIF-1α was significantly upregulated in CRS tissues (p < 0.05) and activated TFRC transcription by binding its promoter, driving M1 macrophage polarization (↑NOS2, IL-6, IL-1β; p < 0.05) and Ferroptosis (↑MDA, Fe²⁺; p < 0.05). Silencing HIF-1α reduced TFRC expression (↓42 %, p < 0.05), suppressed ROS levels (↓35 %, p < 0.05), and inhibited M1 polarization (↓50 % IL-6, p < 0.05). MNP_siHIF-1α (51.0 ± 2.3 nm, ζ-potential: +27.9 mV) achieved 95 % siRNA loading at N/P 5:1 and reduced nasal mucosal thickening (↓60 %, p < 0.01) and inflammatory cytokines (TNF-α: ↓45 %, p < 0.05) in CRS mice. Ferroptosis markers (GPX4: ↑2.1-fold, MDA: ↓55 %) confirmed therapeutic efficacy.

Conclusion: MNP_siHIF-1α suppresses the HIF-1α/TFRC-ROS axis, mitigates M1 macrophage-driven inflammation, and inhibits Ferroptosis, significantly alleviating CRS progression. This study underscores the potential of nanotechnology-based siRNA delivery as a precision therapy for CRS, though further validation of long-term safety and clinical translation is warranted.

Chronic rhinosinusitis; Ferroptosis; Hypoxia-inducible factor 1-alpha; Macrophages; Micellar nanoparticles; Reactive oxygen species; Single-cell RNA sequencing; Transferrin receptor.