AgingResearch.NewsJoin free
Aging Cell

Aging shifts the brain’s natural glow toward red in mice

Experiments in 3- and 21-month-old female mice found larger clumps of fluorescent material in brain immune cells and age-related changes in emitted light.

Paper by Mary Slayo, Loretta Giummarra, Soniya Xavier, 3 more authorsSarah J. Spencer · Justus-Liebig-Universität Gießen
Graphical abstract from Aging Cell
Open the figure at full size
Graphical abstract. Slayo et al., CC BY
Experiments in young and aged female C57BL/6 mice, against small aggregates in young brainsBiomarkers

The catch: The red-shift comparison also differed in aggregate size, mixing size with age

Edited by Boris Djordjevic · AgingResearch.News

Paper
Follow @agingbrief

In an animal experiment, researchers compared two brain regions in 3-month-old and 21-month-old female C57BL/6 mice. They examined autofluorescence, the light some materials emit after illumination, in microglia, immune cells in the brain.

Older mice had a greater volume of fluorescent material in microglia, including an abundance of extra-large clumps. In the arcuate nucleus, one of the regions studied, larger clumps found only in older brains emitted stronger far-red light than the fluorescence in young brains. Blood analysis identified 22 lipids, or fat-like molecules, whose concentrations differed with age. One remained associated with the brain’s light signature after statistical checks accounting for multiple comparisons and validation in a separate group of mice.

Why it matters

Chronic inflammation in the aging brain is linked to neurodegeneration risk. The authors suggest that brain autofluorescence may help monitor brain aging noninvasively.

Caveats

The findings came from comparisons of young and old female mice, not a test of noninvasive monitoring in people. The blood lipid link was an association, not evidence that the lipid caused the brain changes.

Where the evidence stands

Lipid and ceramide metabolism

C, W, M, H: cells, worms or flies, mice, humans. Dark: independent labs found the same change there. Light: one lab or one study. Outline: nothing yet.

Labs are independent when their papers share no last author and no institution.

Against: findings that point the other way from most findings on the same outcome.

Company ties: findings with an author at a company, or from a paper whose competing-interests statement declares ties to one.

Includes the processes named after it and trials of drugs aimed at it.

  • 223 independent labs in 36 countries
  • 16 findings against
  • Funders: National Institutes of Health and others
  • 35 of 323 findings with company ties

Comments

Be the first to comment.

More on Imaging