Histamine alters gene expression in human nasal epithelial cells

Abstract

Background: Airway epithelial cells produce cytokines and participate in the regulation of mucosal immunity. Although nasal epithelial cells express histamine receptors, it is not exactly known how nasal epithelial cells respond to histamine. Objective: The objective of this study was to examine whether histamine can alter the expression of the 4 genes encoding H1 receptor, IL-8, TNF-α and ZO-1 tight-junction protein in cultured nasal epithelial cells. Methods: We added histamine or vehicle to cultured human nasal epithelial cells and extracted RNA from them 4 hours later. After DNase treatment, mRNAs of β-actin, H1 receptor, IL-8, TNF-α, and ZO-1 tight-junction protein were amplified by using RT-PCR. Results: Histamine significantly upregulated IL-8 mRNA expression and significantly downregulated ZO-1 mRNA expression. The latter effect was blocked by pretreatment with mepyramine, an H1 receptor antagonist. Conclusion: The reduction of ZO-1 mRNA by histamine may cause increased permeability of the mucosa during allergic reactions in the nose.