Nicotine in cigarettes promotes chromogranin A production by human periodontal ligament fibroblasts.

OBJECTIVE: The body produces chromogranin A (ChgA) in response to stress as an adaptive reaction. While ChgA is used as an index of autonomic nervous system activity, it is also involved in the immunomodulation system, and an increase in its production in patients with periodontal disease and cigarette smokers has been reported. However, its production in periodontal tissue cells subjected to stress and its immunomodulatory action have not been clarified. To investigate the influence of nicotine on periodontal tissue, we measured ChgA production in nicotine-treated periodontal ligament fibroblasts. DESIGN: Using normal human periodontal ligament-derived fibroblasts (HPdLF) as a periodontal tissue model, untreated cells (control) and cells treated with 10 and 100nM nicotine sulfate corresponding to passive and active cigarette smoking, respectively, were cultured for a specific time. The ChgA level in the culture fluid was measured as ChgA production in HPdLF employing ELISA. ChgA gene expression was quantified employing qPCR. In addition, intracellular localisation was confirmed by immunohistochemical staining. RESULTS: In the control HPdLF group, a low level of ChgA was produced, and immunohistochemical ChgA-positive reactions were observed in the nucleus and cytoplasm. In the nicotine-treated HPdLF group, the ChgA mRNA expression level, protein production, and immunostaining-positive rate increased, and the levels were higher in the cells treated with 10nM nicotine corresponding to passive smoking than in the cells treated with 100nM nicotine corresponding to active smoking. CONCLUSION: Human periodontal ligament-derived fibroblasts (HPdLF) produced ChgA, and nicotine increased ChgA production.

Age is associated with self-reported sleep bruxism, independently of tooth loss.

PURPOSE: The aim of this study was to investigate whether the association between self-reported sleep bruxism (SB) and age is modified by the presence of tooth loss. METHODS: A cross-sectional study was done involving 1,930 residents, ranging from 18 to 89 years of age, who underwent health checkups at the rural health center in Japan. The data collection included oral examinations and self-administrated questionnaires. RESULTS: The prevalence of self-reported SB was 8% (n = 152). It was higher in the groups ranging from 30 to 39 and 40 to 49 years of age in comparison to the groups composed of individuals older than 60 years of age. In the crude analyses, the prevalence of self-reported SB was associated with tooth loss, male, smoking, snoring, sleep talking and a history of childhood teeth grinding. A multiple logistic regression confirmed a significant relationship between self-reported SB and the groups of 30-39 years of age (OR: 2.78, P = 0.003) and 40-49 years of age (OR: 2.31, P = 0.005). Snoring (OR: 2.58, P = 0.001) and known (OR: 8.09, P < 0.001) or unknown (OR: 3.03 P < 0.001%) childhood teeth grinding also showed to be related to self-reported SB. CONCLUSIONS: The present study demonstrates that self-reported SB is associated with age, independently of tooth loss. The associations between SB and age will await further physiological investigations.