Type 2 diabetes mellitus as a periodontitis-related systemic disease and analysis of its pathogenesis mechanism

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K19005
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 57030:Conservative dentistry-related
• Research Institution: Iwate Medical University
• Principal Investigator: Manami Nakasato 岩手医科大学, 歯学部, 助教 (10823841)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: P.gingivalis / 糖尿病 / DPP4

Outline of Final Research Achievements

Porphyromonas gingivalis, a Gram-negative anaerobes, is important pathogen associated with chronic periodontitis. And this bacterium is closely related to systemic diseases, such as type 2 diabetes mellitus. We previously demonstrated more direct involvement, as P. gingivalis dipeptidyl-peptidase (DPP)4 was shown to degrade incretin peptides, resulting in elevation and prolongation of postprandial hyperglycemia in a mouse model. In this study, we assessed whether other DPPs could degrade incretins as same as DPP4. P. gingivalis DPP7 has more potent hydrolyzing activity toward incretins and other gastrointestinal peptides than DPP4. In addition, intravenous administration of DPP7 in mice decreased serum levels of active GLP-1 and blood glucose levels. DPP7 was also shown to hydrolyze insulin. In summary, P. gingivalis is important pathogen associated with type 2 diabetes mellitus.

Free Research Field

歯周療法学分野

Academic Significance and Societal Importance of the Research Achievements

歯周病原細菌P. gingivalisのDPP4 やDPP7 はインクレチンやインスリンなどの血糖値コントロールにかかわる生理活性物質を切断・不活性化することから，口腔局所に感染しているの本菌の血流への侵入が2型糖尿病の病態形成にかかわることが強く示唆された．以上のことから，歯科処置による口腔内のP. gingivalisの減少は2型糖尿病の予防や病態改善に寄与するものと推察される．