Effect and mechanism of PPAR gamma agonist on allergic rhinitis in mice / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To invest igate the therapeutic effect and mechanism of PPAR gamma agonist on allergic rhinitis(AR) in mice. METHODS AR murine model was established by OVA sensitization and challenge. The behavior observation was used to understand the improvement effect of PIO on AR symptoms. The morphological characteristics of nasal tissues were observed by HE staining. The total RNA was extracted to investigate the level of mRNA expression of Foxp3, T-bet and GATA-3. The changes of CD4+Foxp3+T cells in spleen of mice were analyzed by flow cytometry. RESULTS BALB/c mice received OVA sensitization followed by OVA intranasal challenge, the frequencies of sneezing and nose-scratching increased signif icantly in AR group compared with control group. The frequencies decreased significantly in PIO group, compared with AR group. The continuity of nasal mucosa ciliated columnar epithelium in AR group was destroyed and appeared to be repaired in PIO group. Inflammatory cells infiltration was also markedly decreased by PIO treatment. PIO significantly increased the expression of Foxp3 mRNA(P ＜0.001) compared with AR and control group. There was no significant difference in T-bet between PIO group and AR group, but the expression of GATA-3 mRA in PIO group was significantly lower than AR group. The proportion of CD4+Foxp3+T cells in AR group (4.43％±0.25％) decreased compared with control group (5.19％±0.39％) (P ＜0.001). PIO treatment induced production of Tregs (6.35％±0.37％) compaered with control group(P ＜0.001). CONCLUSION PPAR-gamma agonist can effectively alleviate allergic symptoms of mice and regulate the balance of Th1/Th2. The role of PPAR gamma agonist in the treatment of AR may be the amplification of Tregs by promoting Foxp3 expression.