A cross-sectional study of functional and metabolic changes during aging through the lifespan in male mice.
Abstract
Aging is associated with distinct phenotypical, physiological, and functional changes, leading to disease and death. The progression of aging-related traits varies widely among individuals, influenced by their environment, lifestyle, and genetics. In this study, we conducted physiologic and functional tests cross-sectionally throughout the entire lifespan of male C57BL/6N mice. In parallel, metabolomics analyses in serum, brain, liver, heart, and skeletal muscle were also performed to identify signatures associated with frailty and age-dependent functional decline. Our findings indicate that declines in gait speed as a function of age and frailty are associated with a dramatic increase in the energetic cost of physical activity and decreases in working capacity. Aging and functional decline prompt organs to rewire their metabolism and substrate selection and towards redox-related pathways, mainly in liver and heart. Collectively, the data provide a framework to further understand and characterize processes of aging at the individual organism and organ levels.
Data availability
This study did not generate datasets or code. However, we are citing one of our previously published raw microarray datasets that was deposited to the NCBI GeneExpressionOmnibus database under accession number GSE81959.
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Effects of Sex, Strain, and Energy Intake on Hallmarks of Aging in MiceNCBI Gene Expression Omnibus, GSE81959.
Article and author information
Author details
Funding
National Institute on Aging (AG000335-04)
- Rafael de Cabo
The research was supported by the Intramural Research Program of the National Institute on Aging
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (ACUC) protocol of the National Institute on Aging (Protocol Number: TGB-277-2022)
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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