RGFP966, a selective HDAC3 inhibitor, ameliorates allergic and inflammatory responses in an OVA-induced allergic rhinitis mouse model.

RGFP966 is a selective inhibitor of histone deacetylase 3 (HDAC3) playing crucial roles in triggering allergic and inflammatory responses. Whereas, its role in allergic rhinitis (AR) remains uncertain. This study sought to illustrate the role and mechanism of HDAC3 inhibitor RGFP966 on allergic and inflammatory responses in murine AR. RGFP966 administration was applied on murine AR. HE staining, PAS staining, toluidine blue staining, immunohistochemistry staining and real-time PCR methods were used to assess eosinophils, goblet cells, mast cells, HDAC3 positive cells and mRNA levels in nasal tissues of mice. HDAC3 activities in nasal tissues were quantified with HDAC3 Activity Assay Kit. We collected blood and nasal lavage fluid (NLF) of mice for assaying IgE, inflammatory cytokines and inflammatory cells. Results indicated that RGFP966 intervention attenuated sneezing, nose rubbing, IgE, inflammatory cytokines, eosinophils, goblet cells, mast cells, inflammatory cells, HDAC3 levles and activities in RGFP966 treated mice. In conclusion, RGFP966 might reduce HDAC3 expression and HDAC3 activities, and then eosinophils and mast cells recruitment, goblet cells proliferation and inflammatory cytokines levels are decreased, resulting in the alleviation of allergic and inflammatory responses in AR mice.