Effects of oral disease on cardiac function

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K12067
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social dentistry
• Research Institution: Tsurumi University
• Principal Investigator: Ohnuki Yoshiki 鶴見大学, 歯学部, 講師 (50288114)
• Co-Investigator(Kenkyū-buntansha): 梅木 大輔 鶴見大学, 歯学部, 助教 (10514937) ; 成山 明具美 鶴見大学, 歯学部, 助教 (90440304)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 不正咬合 / 心筋 / 線維化 / アポトーシス / オートファジー / 酸化ストレス / プロプラノロール

Outline of Final Research Achievements

Various types of stress are associated with increased incidence of cardiovascular disease, but the relationship between occlusal disharmony and cardiovascular disease remain poorly understood. Therefore, in this work, we examined the effects of occlusal disharmony on cardiac homeostasis in bite-opening (BO) mice, in which a 0.7 mm space was introduced by cementing a suitable appliance onto the mandibular incisor. Sympathetic nervous activity and serum corticosterone, a key biomarker for stress, were significantly increased by the 14 days of BO treatment. Cardiac function was significantly decreased by the BO treatment, but propranolol, a non-selective β-blocker, ameliorated the dysfunction. Cardiac fibrosis, myocyte apoptosis and myocyte oxidative DNA damage were significantly increased by the BO treatment, but propranolol blocked these changes. These results suggest that occlusal disharmony might affect cardiac homeostasis via alteration of the autonomic nervous system.

Free Research Field

生理学

Academic Significance and Societal Importance of the Research Achievements

口腔疾患と心疾患の関連性は疫学調査から示唆されているが、その因果関係やメカニズムに関する詳細な報告は少ない。本研究では、不正咬合モデルマウスを用い、口腔機能障害と心疾患の因果関係およびその分子機序を解明した。また、得られた研究成果から、正常な口腔機能の維持が心疾患の予防につながることも示唆された。高齢化社会を迎え、近年増加傾向にある歯周病などの口腔疾患と、死亡原因第2位の心疾患との関連性を調べた本研究の意義はきわめて高い。