The essential oils from Asarum sieboldii Miq. Alleviate allergic rhinitis by regulating tight junction and...

Essential oils from herbs, including those from Asarum sieboldii Miq., are readily absorbed through mucous membranes, explaining their widespread use in inhalation formulations. Asarum sieboldii Miq. has a long history of traditional use for various medicinal purposes, attributed to its anti-inflammatory, antiallergic, and antioxidant properties. Despite research on Asarum sieboldii Miq. for allergic inflammation in respiratory diseases, detailed mechanistic studies are still lacking.

We utilized bioinformatics and network pharmacology to identify the effectiveness of Asarum sieboldii Miq. in treating allergic rhinitis (AR). Our aim is to elucidate the potential therapeutic effects of essential oil derived from Asarum sieboldii Miq. (ASO), which is recognized for its diverse pharmacological properties, on AR.

Common genes associated with the active compounds of ASO and AR were utilized to construct a related network and predict their mode of action. AR was induced in BALB/c mice by exposing them to ovalbumin (OVA) and particulate matter 10 (PM₁₀; airborne particles <10 μm). With induction, aerosolized ASO (0.0002% and 0.02%) were administered via nebulizer for 5 min per day, three times a week for 7 weeks. Mice were examined for histopathological changes in the nasal tissue, nasal epithelial inflammation, the production of allergen-specific cytokine response in vitro and in vivo.

The common genes of ASO and AR were predicted to include 'Tight junction', 'Apoptosis', and 'TGF-beta signaling', which are the main pathways of pathogenesis in AR. Consistent with network prediction, nebulized ASO treatment effectively improved the expression of tight junction-related factors, zonula occludens-1, claudin-1, occludin and junction adhesion molecule A, in OVA + PM₁₀ induced mice. Additionally, it reduced hyperplasia of nasal epithelial thickness, goblet cell counts, and inflammatory cell infiltration (eosinophils, neutrophils, macrophages, and lymphocytes) in nasal lavage fluid, while also alleviating allergic symptoms such as sneezing, rubbing, and serum IgE level when compared to the AR-induced group. The levels of mRNA and protein expression related to tight junctions were restored to normal levels by ASO, as confirmed in immunofluorescence analysis in nasal epithelial cells RPMI2650. Furthermore, treatment of ASO on PM₁₀-treated nasal epithelial cells significantly reduced ROS production, recovered mitochondria membrane potential, and inhibition of the production of proinflammatory cytokines (TNF-α, IL-4, and IL-13) and inflammatory mediators linked to the MAPK/NF-κB signaling pathways.

Intranasal nebulization of ASO improves TJs and alleviates allergic nasal inflammation in AR. It supports the potential pharmaceutical application of ASO treatment for AR.