Role of Periostin in the Development of Nasal Hyperresponsiveness in Mice with Allergic Rhinitis.

Periostin is a matricellular protein induced by type 2 cytokines. It has been shown to play important roles in airway inflammation and tissue remodeling. Although periostin has been studied in asthma and chronic rhinosinusitis, its role in allergic rhinitis (AR) and nasal hyperresponsiveness (NHR) is unclear. This study aimed to determine whether periostin is involved in the development of NHR in AR. A murine AR model was established by sensitization and repeated intranasal challenges with Japanese cedar pollen (JCP). In this animal model of AR, an increase in nasal responsiveness to histamine was observed 24 h after the last JCP challenge, indicating the development of NHR. RT-qPCR analysis revealed that the JCP-induced NHR was accompanied by increased periostin gene expression. Immunohistochemical examinations demonstrated the expression of integrin subunits α(V) (Itgav), β(3) (Itgb3) and β(5) (Itgb5), which are known as receptors for periostin, in the nasal mucosa, especially in the mucosal epithelium. Notably, repeated intranasal administration of recombinant periostin to healthy I mice reproduced the NHR phenotype, as observed in AR model mice. These findings suggest that periostin upregulation in the nasal mucosa plays a causal role in the development of NHR, a key feature of AR.