BACKGROUND: Asthma patients exhibit elevated airway mucus secretion. Small interfering RNA (siRNA) targeting the mucin MUC5AC delivered by lipid nanoparticles (LNPs) is promising but limited by low transfection efficiency. Protopanaxadiol (PPD), protopanaxatriol (PPT), and ginsenoside Rh2 (GR2) were chosen because their dammarane skeleton preserves membrane-insertion capacity for endosomal escape, whereas bulkier multi-glycosylated ginsenosides adversely affect LNP size and stability.
PURPOSE: In this study, we designed novel inhaled LNPs incorporating ginseng-derived cholesterol analogs to enhance therapeutic efficacy against asthma.
METHODS: PPD and PPT were used as membrane components to formulate anti-MUC5AC siRNA-loaded LNPs (designated as DLNPs and TLNPs). Flow cytometry and confocal laser scanning microscopy (CLSM) were employed to evaluate the cellular uptake and lysosomal escape of LNPs. An asthmatic mouse model was established to assess therapeutic effects of DLNPs and TLNPs through pathological section analysis and determination of inflammatory cytokine levels.
RESULTS: The data showed that these novel formulations enhanced cellular uptake by airway epithelial cells (AECs) and promoted siRNA escape from lysosomes, thereby improving pulmonary delivery efficiency. TLNPs, in particular, demonstrated superior performance. Furthermore, DLNPs and TLNPs exerted multifaceted anti‑asthmatic effects in vivo, as evidenced by significant suppression of MUC5AC overexpression in AECs, attenuation of inflammatory cell infiltration, and reduction in the secretion of the critical cytokines IL‑4 and IL‑13.
CONCLUSION: Overall, our findings indicate that ginseng-derived PPD and PPT effectively enhance siRNA delivery and mitigate asthma symptoms through dual inhibition of MUC5AC overexpression and airway inflammation. These cholesterol analogs represent promising carrier materials for LNP-based pulmonary therapeutics.
