Anti-allergic function of -Tocopherol is mediated by suppression of PI3K-PKB activity in mast cells in mouse model of allergic rhinitis

Main Article Content

Geping Wu
Hongyan Zhu
Xinyang Wu
Lili Liu
Xingkai Ma
Yifang Yuan
Xingli Fu
Ling Zhang
Yan Lv
Di Li
Jianyong Liu
Jianbin Lu
Yan Yu
Menglin Li

Keywords

α-TCP, Allergic rhinitis, PI3K-PKB, Animal model, OVA

Abstract

Background: Alpha-Tocopherol (-TCP), one major form of vitamin E, has been known as a treatment for airway allergic inflammation. However, the role and mechanism of -TCP in treating allergic rhinitis remains unclear.


Objective: In this study, we examined the inhibitory function of -TCP in a mouse model of allergic rhinitis.


Methods: Allergic phenotype was examined by hematoxylin and eosin staining. Total IgE, OVAspecific IgE, OVA-specific IgG1 and OVA-specific IgG2a levels were examined by ELISA. mRNA expression was measured by qPCR, protein levels were examined by Western Blot.


Results: Histological analysis of the nasal membranes revealed that there was a significant reduction in inflammatory cells appearance in cross-sections in alpha-TCP treatment of Ovalbumin (OVA)-sensitized mice compared to OVA-sensitized animals. In addition, eosinophils were significantly reduced in nasal mucosa of alpha-TCP treatment of OVA-sensitized mice compared to the OVA group. Lower total IgE, OVA-specific IgE, OVA-specific IgG1 and OVA-specific IgG2a levels were found in alpha-TCP treatment of OVA-sensitized mice compared to the OVA group. Furthermore, we found that the subepithelial distribution of tryptase positive mast cells was reduced in the alpha-TCP treatment of OVA-sensitized mice. More importantly, the PI3K-PKB pathway was suppressed by -TCP in mast cells.


Conclusions: Our results demonstrated that -TCP-mediated suppression of PI3K-PKB activity in mast cells is a potential mechanism of anti-allergic function of -TCP.

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