Effect of Xiaoqinglong decoction on gut-lung axis microbiota in allergic rhinitis mice.

OBJECTIVE: This study aimed to characterize the effects of Xiaoqinglong decoction (XQLD) on the microbiota of the gut-lung axis at three key sites-the nasal cavity, lungs, and gut-in Allergic rhinitis (AR) mice, with particular attention to site-specific response patterns and their potential links to AR disease resolution. METHODS: An ovalbumin-induced AR mouse model was established, with mice assigned to control, AR, loratadine, and XQLD groups. Intervention outcomes were assessed via behavioral observation, ELISA, histopathology, and 16S rRNA gene sequencing, followed by correlation analysis. RESULTS: Compared with the AR group, XQLD significantly reduced nasal symptoms, serum OVA-sIgE and IL-4 levels, and nasal mucosal injury. AR induction markedly altered the nasal and gut microbiota, whereas the lung microbiota remained relatively stable. XQLD significantly increased nasal Oxalobacteraceae and significantly decreased gut Rikenellaceae and Odoribacter. Gut Lactobacillaceae, Lactobacillus, and Allobaculum showed upward trends, whereas Helicobacter showed a slight downward trend. Several nasal and gut taxa were significantly associated with nasal symptoms and Th2-related inflammatory indicators. CONCLUSION: XQLD differentially modulates the gut-lung axis microbiota in AR mice, with the most marked changes observed in the gut, which may correlate with its therapeutic effects and merit further mechanistic exploration.