1. Astroglial glucose uptake determines brain FDG-PET alterations and metabolic connectivity during healthy aging in mice.
- Author
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Bartos LM, Kunte ST, Wagner S, Beumers P, Schaefer R, Zatcepin A, Li Y, Griessl M, Hoermann L, Wind-Mark K, Bartenstein P, Tahirovic S, Ziegler S, Brendel M, and Gnörich J
- Subjects
- Animals, Mice, Male, Female, Aging metabolism, Radiopharmaceuticals pharmacokinetics, Neurons metabolism, Healthy Aging metabolism, Microglia metabolism, Fluorodeoxyglucose F18 pharmacokinetics, Astrocytes metabolism, Positron-Emission Tomography methods, Glucose metabolism, Brain metabolism, Brain diagnostic imaging, Mice, Inbred C57BL
- Abstract
Purpose: 2-Fluorodeoxyglucose-PET (FDG-PET) is a powerful tool to study glucose metabolism in mammalian brains, but cellular sources of glucose uptake and metabolic connectivity during aging are not yet understood., Methods: Healthy wild-type mice of both sexes (2-21 months of age) received FDG-PET and cell sorting after in vivo tracer injection (scRadiotracing). FDG uptake per cell was quantified in isolated microglia, astrocytes and neurons. Cerebral FDG uptake and metabolic connectivity were determined by PET. A subset of mice received measurement of blood glucose levels to study associations with cellular FDG uptake during aging., Results: Cerebral FDG-PET signals in healthy mice increased linearly with age. Cellular FDG uptake of neurons increased between 2 and 12 months of age, followed by a strong decrease towards late ages. Contrarily, FDG uptake in microglia and astrocytes exhibited a U-shaped function with respect to age, comprising the predominant cellular source of higher cerebral FDG uptake in the later stages. Metabolic connectivity was closely associated with the ratio of glucose uptake in astroglial cells relative to neurons. Cellular FDG uptake was not associated with blood glucose levels and increasing FDG brain uptake as a function of age was still observed after adjusting for blood glucose levels., Conclusion: Trajectories of astroglial glucose uptake drive brain FDG-PET alterations and metabolic connectivity during aging., Competing Interests: Declaration of competing interest MB is a member of the Neuroimaging Committee of the EANM. MB received speaker honoraria from Roche, GE healthcare and Life Molecular Imaging, has advised Life Molecular Imaging and is currently in the advisory board of MIAC. All other authors do not report any conflict of interest., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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