A1 Refereed original research article in a scientific journal
Impact of Day Length on Brain Glucose Metabolism in Men: A Large-Scale Repeated Measures PET Study
Authors: Pak, Kyoungjune; Shin, Seunghyeon; Kim, Keunyoung; Kim, Jihyun; Nam, Hyun-Yeol; Nummenmaa, Lauri; Nuutila, Pirjo; Liu, Xingdang; Sun, Lihua
Publisher: SAGE Publications
Publication year: 2025
Journal: Journal of Biological Rhythms
Journal name in source: Journal of Biological Rhythms
Article number: 07487304251360874
ISSN: 0748-7304
eISSN: 1552-4531
DOI: https://doi.org/10.1177/07487304251360874
Web address : https://doi.org/10.1177/07487304251360874
The brain is the most energy-demanding organ, yet whether cerebral energy homeostasis exhibits seasonal rhythmicity remains unclear. In this study, 432 healthy men underwent a health checkup program with fasting-state brain [18F]fluorodeoxyglucose positron emission tomography (PET) scanning twice: first at the baseline and then at the 5-year follow-up. We analyzed the effect of day length on brain glucose uptake separately for both time points. In both baseline and follow-up scans, day length on the day of imaging significantly predicted glucose uptake in the socio-emotional circuit. A longer day length was associated with increased glucose uptake in the cuneus, precuneus, orbitofrontal cortex, pre- and postcentral gyrus, superior and middle temporal gyrus, posterior cingulate cortex, insula, and frontal pole. This large-scale longitudinal PET study provides landmark evidence for the impact of daylight exposure on brain glucose metabolism. Findings disclose the baseline seasonal variation of brain energy consumption in men.
Funding information in the publication:
This study was supported by the National Research Foundation of Korea (2020R1F1A1054201; K.P.), Sigrid Juselius Stiftelse and European Research Council Advanced Grant (101141656; L.N.) the National Natural Science Foundation of China (82272042; X.L.), and Fudan University affiliated with Huashan Hospital start-up funding (L.S.). X.L. received funding from the Pudong New Area Clinical Characteristic Discipline Project (No. PWYts2021-01), Clinical Research Program of Health Industry of Shanghai Municipal Commission of Health (202150002), Pudong Hospital, Fudan University, College Level Project (YJYJRC202108/ YJYJRC202101/Zdzk2020-14).
