Development of evaluation method for glucose oxidation capacity of different organs by 13C-glucose breath test and investigation of pathogenesis of abnormal glucose metabolism

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K07906
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 52010:General internal medicine-related
• Research Institution: Tohoku Medical and Pharmaceutical University (2020-2021); Tohoku University (2019)
• Principal Investigator: Sawada Shojiro 東北医科薬科大学, 医学部, 准教授 (60509420)
• Co-Investigator(Kenkyū-buntansha): 高橋 圭 東北大学, 医学系研究科, 助教 (00644808)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: ブドウ糖呼気試験 / 糖代謝異常の早期診断法

Outline of Final Research Achievements

After absorption in the small intestine, orally ingested glucose enters the liver, where some is stored as hepatic glycogen and the rest skips through the liver to be consumed in skeletal muscle. Hepatic glycogen storage and skeletal muscle glucose uptake require insulin action. It has been reported that postprandial hyperglycemia precedes the onset of diabetes. In the present study, glucose labeled with stable isotopes was orally administered to healthy subjects, and the ratio of stable isotopes in carbon dioxide metabolized and produced by the individual was measured as an indicator of glucose oxidation in the individual (glucose breath test). The glucose breath test showed that the excretion of labeled carbon dioxide was low when glycogen accumulation in the liver was expected to be high.

Free Research Field

糖尿病

Academic Significance and Societal Importance of the Research Achievements

糖尿病発症前にハイリスク集団を同定し介入することは予防医学の観点からも重要である。糖尿病に先立ち、肝臓では食後のブドウ糖取込みが低下するため“食後高血糖”を呈する。肝臓ではインスリン作用により経口摂取されたブドウ糖をグリコーゲンとして肝に貯蔵するが、このようなプロセスを簡便な臨床検査で測定できれば、糖尿病発症前のハイリスク集団の同定につながる可能性がある。今回の研究では、肝臓でのグリコーゲン蓄積が多いと予想される場合に、ブドウ糖呼気試験で標識された二酸化炭素の排泄量が低値をきたすことを見出した。生体サンプルとして採血が不要な検査であり、呼気だけで測定できることは臨床応用に向け社会的意義は高い。