Temporal incompatibility between the external environment and the organism on fertility

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K09674
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56040:Obstetrics and gynecology-related
• Research Institution: Osaka Metropolitan University (2022); Osaka City University (2020-2021)
• Principal Investigator: Hashimoto Shu 大阪公立大学, 大学院医学研究科, 特任教授 (30570949)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 時間制限給餌 / 卵母細胞 / 生殖能力 / サーカディアンリズム / マウス

Outline of Final Research Achievements

We assessed the effects of feeding regimen (ad libitum vs. time-restricted food access) and type of food (normal chow (NC: 12% fat) vs. moderately high calorie diet (mHCD: 31% fat)) on fertility competence of female mice. Mice fed mHCD had higher number of oocytes than mice fed NC. On the other hand, when mice were fed NC under time-restricted access to food (NT), the developmental rate to the blastocyst per number of normally fertilized ova was significantly decreased compared to others. The reactive oxygen species (ROS) level in oocytes increased in time-restricted food access and NC group. Transcriptome analysis of whole ovarian tissues from these mice showed a change in the cholesterol metabolism among the four groups. Time-restricted food access decreased serum LDL cholesterol level in both NC and mHCD groups. Moreover, the number of atretic follicles increased in NT mice compared to ad libitum food access mice.

Free Research Field

生殖工学

Academic Significance and Societal Importance of the Research Achievements

通常の栄養状態でのカロリーの過剰摂取は、生殖能力に悪影響を及ぼすことが分かっています。TRFは、肥満化することなくマウスの健康を維持するために開発されました。一方、TRFはカロリーの蓄積を抑制し、カロリーの消費を促進することで、生活習慣病のリスクを低減することが示されています。従って、普通食とTRFを併用すると、コレステロール値が低下し、卵子の質の低下につながる可能性もある。