Does lactate promote mitochondrial biogenesis in hippocampus following a single bout of intense exercise?

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K20051
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 59020:Sports sciences-related
• Research Institution: Nippon Medical School
• Principal Investigator: Park Jonghyuk 日本医科大学, 大学院医学研究科, ポストドクター (80835843)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 一過性運動 / 高強度 / 乳酸 / 海馬 / ミトコンドリア生合成

Outline of Final Research Achievements

Regular exercise training induces mitochondrial biogenesis in the hippocampus. However, it remains unclear whether a single bout of exercise would increase hippocampal mitochondrial biogenesis. Eight-week-old male ICR mice were subjected to a single bout of exercise at three different intensities. High-intensity, but not low- or moderate-intensity, increased blood lactate concentration and enhanced PGC-1α mRNA expression and mitochondrial DNA (mtDNA) in the hippocampus. Moreover, I.p. lactate injection increased hippocampal extracellular lactate concentration to the same as blood lactate level, but this was suppressed by administering UK5099, a monocarboxylate transporters inhibitor. Hippocampal MCT1, and MCT2 mRNA expression, except MCT4, also increased after high-intensity exercise, which was abolished by UK5099 administration. Thus, a single bout of exercise above the lactate threshold could provide an effective strategy for increasing mitochondrial biogenesis in the hippocampus.

Free Research Field

運動生理学

Academic Significance and Societal Importance of the Research Achievements

運動がミトコンドリア生合成にもたらす影響を調べた研究が増えてきている。しかし、それは長期間のトレーニングによる効果を示す研究結果が多い。本研究の成果は、一過性の運動、特に乳酸上昇を引き起こす強度の運動が脳、とりわけ認知機能を担う海馬領域のミトコンドリア生合成を高めることを明らかにした。一方、アルツハイマー病由来の認知機能低下では脳のミトコンドリア量の低下も報告されており、運動により脳のミトコンドリア生合成を高めることが運動による認知機能向上の重要な要因である可能性がある。従って、この後、健康の維持増進のために高強度運動を推奨していく上での重要な基礎的研究結果となりえることが期待される。