Research on induction and maintenance of torpor

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K08898
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 54040:Metabolism and endocrinology-related
• Research Institution: Kurume University
• Principal Investigator: SATO Takahiro 久留米大学, 付置研究所, 准教授 (50368883)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: グレリン

Outline of Final Research Achievements

In this study, the torpor model mice established by the principal investigator were used to elucidate the mechanisms of induction and maintenance of the torpor. Quantitative PCR array analysis showed that ghrelin (hypothalamic ghrelin) content in the brain was high in the torpor model mice. Therefore, intracerebroventricular administration of ghrelin caused a transient decrease in body temperature. At this time, when ghrelin was administered continuously from the periphery with a mini-pump implanted in the abdominal cavity in advance, the torpor was completely induced and maintained. In other words, brain ghrelin not only induces torpor, but may also maintain sustained hypothermia by increasing the sensitivity of peripherally secreted ghrelin to the brain. Taken together, ghrelin is a peptide required for induction and maintenance of the torpor.

Free Research Field

内分泌学、神経内分泌学

Academic Significance and Societal Importance of the Research Achievements

トーパーは、寒冷時や飢餓時などに見られる能動的な低代謝状態で、著しい体温低下を特徴とする生理現象である。類似の現象として低体温症が知られているが、低体温症とは異なって脳機能に障害を残すことはない。このことは、トーパーの誘導や維持機構の解明が、長期間の臓器保存といった次世代型医療に展開できる可能性を示唆している。さらに、能動的低代謝を特徴とするトーパーの全貌を明らかにできれば、肥満症や糖尿病の新たな治療戦略の創出にも結びつくことが期待できる。