Xuanfei Pingchuan Decoction Attenuates Ovalbumin-Induced Allergic Asthma Mice Through Regulating Th17/Treg Immune Imbalance

Objective This study aimed to investigate the interventional effects and potential underlying mechanisms of Xuanfei Pingchuan Decoction on ovalbumin (OVA)-induced allergic asthma (AA) in mice. Methods Liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) was used to analyze and identify the constituents of Xuanfei Pingchuan Decoction. An allergic asthma (AA) mouse model was induced by using OVA combined with aluminum hydroxide. The resistance index (RI) in the airway was analyzed with an AniRes2005 animal pulmonary function analyzer. H&E staining was performed to evaluate pathological changes in the lung tissue. Apoptotic cells in lung tissue were assessed via TUNEL staining. The percentage of eosinophils (EOS) in bronchoalveolar lavage fluid (BALF) and the ratio of Th17 to Treg cells in the splenic tissue and peripheral blood were determined by flow cytometry. The levels of IL-6, IL-17A, and IL-10 in the BALF were determined by ELISA. The mRNA expression of RORγt and Foxp3 in lung tissue was measured with RT‒qPCR. Biochemical kits were used to measure the levels of total IgE, sIgE (specific IgE), and IgG1 in the serum. Results A total of 340 active constituents were identified from Xuanfei Pingchuan Decoction by LC-MS/MS analysis. Xuanfei Pingchuan Decoction reduced the RI; alleviated histopathological damage; decreased the apoptosis rate; reduced the proportion of EOS; down-regulated the mRNA levels of IL-6, IL-17A, and RORγt; up-regulated the mRNA levels of IL-10 and Foxp3; reduced the levels of IgE, sIgE, and IgG1; and regulated the Th17/Treg balance in AA mice. Conclusions Xuanfei Pingchuan Decoction improved airway inflammation in OVA-induced AA mice, and the underlying mechanism may be related to the regulation of Th17/Treg immune imbalance.