AR is a global health problem and closely related to environmental factors. UA has potential in the treatment of allergic inflammation. The effects of UA intervention on PM2.5-induced AR remain uncertain. This study was done to explore the effects of UA intervention on PM2.5-induced AR that remain uncertain.

The major area of focus was to assess the effects of UA on nasal symptoms and the expression of T-helper (Th)1–Th2-related cytokines in a rat model of AR after fine particulate matter exposure.

40 healthy female Sprague-Dawley rats in total were randomly divided into 4 groups PM2.5-exposed AR group exposed to 200 g/m3 PM2.5 for 30 days via inhalation, and a group with UA intervention to the AR model after PM2.5 exposure. UA intervention was adopted after PM2.5 exposure in the UA group.

In the AR group, hematoxylin and eosin staining showed a disordered arrangement of the nasal mucosa epithelium, cell shedding, eosinophilic infiltration, swelling of the glands, and submucosal vascular congestion.

The study concluded through its findings that the UA could relieve nasal symptoms caused by PM2.5 exposure, the possible mechanism of which is to inhibit the expression of Th2 cytokines, eosinophilic infiltration, and specific IgE production.