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Mechanisms of Ageing and Development

Free-floating DNA levels differed across human age groups

In a cross-sectional study of 418 people aged 7–95, free-floating DNA levels increased across ages 7–80 but were lower at 81–95 than at 61–80.

Paper by Elizaveta Ershova, Pavel Umriukhin, Julia Chudakova, +3 more authorsAlexey Moskalev
Figure 1 from Mechanisms of Ageing and Development
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Figure 1. Ershova et al.

Our read

Mechanisms
Studied:
Cross-sectional study of 418 community-dwelling participants aged 7–95 years
What changed:
Free-floating DNA levels rose across ages 7–80, but were lower at 81–95 than at 61–80
The catch:
Individual changes in DNA levels over time were not measured
Why it’s aging research:
Change across ages, or exceptional longevity.

Editor of record: Boris Djordjevic · AgingResearch.News

Paper
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Among 418 community-dwelling participants aged 7–95, a cross-sectional observational study measured free-floating DNA in plasma, the liquid part of blood, and the activity of enzymes that break down DNA. Researchers also measured oxidative damage, a type of chemical damage, in this DNA from 333 participants.

DNA levels increased and enzyme activity decreased across ages 7–80. Participants aged 81–95 had lower DNA levels and higher enzyme activity than those aged 61–80. The ratio of DNA levels to enzyme activity peaked at ages 61–80 and declined thereafter. Oxidative damage in the DNA increased with age and was highest in the oldest group. An exploratory index combining DNA levels, oxidative damage and enzyme activity increased until about age 45 and then stabilized.

Why it matters

Free-floating DNA is an emerging marker of aging. The findings support investigating how the body breaks down oxidized DNA outside cells as people age.

Caveats

The cross-sectional measurements compared different people at different ages rather than tracking individuals over time. Differences between age groups may reflect differences between participants as well as aging.

Where the evidence stands

Oxidative stress and ROS signaling

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  • 138 of 2,983 findings with company ties

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