Nicotine up-regulates IL-8 expression in human gingival epithelial cells following stimulation with IL-1 beta or P. gingivalis lipopolysaccharide via nicotinic acetylcholine receptor signalling

作者：Kashiwagi Yoichiro; Yanagita Manabu^*; Kojima Yuko; Shimabukuro Yoshio; Murakami Shinya

来源：Archives of Oral Biology, 2012, 57(5): 483-490.

DOI：10.1016/j.archoralbio.2011.10.007

• Nicotine
• Gingival epithelial cells
• IL-8
• Innate immunity

Objective: Cigarette smoking is an important risk factor for periodontal disease. The aim of this study is to evaluate the effect of nicotine, a major component of cigarette smoke, on interleukin-8 (IL-8) production and cellular signalling via nicotinic acetylcholine receptors (nAChRs) in human gingival epithelial cells (HGECs).
Design: Messenger RNA (mRNA) expression of nAChR subunits in three different HGEC lines (epi 4, Tfx and E6E7) was assessed using reverse transcription-polymerase chain reaction (RT-PCR). HGECs were stimulated by 1 x 10(-3) M nicotine in the presence or absence of IL-1 beta or Porphyromonas gingivalis lipopolysaccharide (LPS). IL-8 production was then examined using real-time PCR and enzyme-linked immunosorbent assay. Nicotine-mediated signalling in the epi 4 cell line was also evaluated by Western blotting.
Results: HGECs expressed several nAChR subunits. Nicotine increased the secretion of IL-8 from HGECs that were cultured in the presence of IL-1 beta or P. gingivalis LPS and also induced the phosphorylation of extracellular signal-regulated kinase (ERK) in epi 4. Pretreatment with non-selective nAChR antagonist or intracellular calcium chelator reduced the nicotine-induced phosphorylation of ERK. Furthermore, nicotine-induced IL-8 secretion was decreased by pretreatment with non-selective nAChR antagonist, ERK1/2 inhibitor or intracellular calcium chelator.
Conclusion: These findings indicate that nicotine increases IL-8 production in gingival epithelial cells via ERK phosphorylation following Ca2+ signalling after nAChR activation.

• 出版日期2012-5