Luteolin restored Treg/Th17 balance to ameliorate allergic rhinitis in a mouse model

Luteolin (LO) has been reported to be a potential drug for allergic rhinitis (AR). This paper explored the mechanism of LO in AR.Mice were treated with ovalbumin (OVA) to construct an AR model in vivo before LO or 3-methyladenine (3-MA) treatment. The frequency of nasal sneezing was counted. The nasal mucosa thickness was assessed by hematoxylin-eosin staining assay. The levels of anti-OVA-immunoglobulin E (IgE)/IgG2a, autophagy-related factors (Beclin1, LC3II/LC3I), and T helper cell 17 (Th17)/regulatory T cell (Treg) markers (interleukin (IL)-17A, retinoic acid receptor-related orphan nuclear receptor γt (RORγt)/IL-10, forkhead box P3 (Foxp3)) were detected through enzyme-linked immunosorbent assay, western blot, and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Flow cytometry assay was performed to test the percentage of Th17 and Treg cells.The nasal sneezing frequency, nasal mucosa thickness, and levels of anti-OVA-IgE, Beclin1, LC3II/LC3I, IL-17A as well as RORγt were enhanced whereas anti-OVA-IgG2a, IL-10, and Foxp3 levels were inhibited in a mouse model of OVA-induced AR, which were reversed by LO or 3-MA treatment.LO restored Treg/Th17 balance to ameliorate AR in a mouse model.