Aging Brains Show an organized pattern of Cell Death

Amazing stuff!

"As the brain ages, it loses cells. Researchers have predominantly focused on the effects of cell death in brain areas responsible for cognition, but the cerebellum, most well-known for coordinating motor function, has emerged as an important player in the aging brain too. The primary cell type in the cerebellum, the Purkinje cell, degenerates even in healthy individuals. However, this process and its role in aging are understudied.

... researchers ... demonstrated that otherwise healthy but aged mice experience neurodegeneration of Purkinje cells in a consistent, striped pattern. The findings provide a roadmap to studying the mechanisms of aging and the effects of neurodegeneration on cognitive and motor function. ..."

From the abstract:

"Age-related neurodegenerative diseases involve reduced cell numbers and impaired behavioral capacity.

Neurodegeneration and behavioral deficits also occur during aging, and notably in the absence of disease. 

The cerebellum, which modulates movement and cognition, is susceptible to cell loss in both aging and disease.

Here, we demonstrate that cerebellar Purkinje cell loss in aged mice is not spatially random but rather occurs in a pattern of parasagittal stripes.

We also find that aged mice exhibit impaired motor coordination and more severe tremor compared to younger mice.

However, the relationship between patterned Purkinje cell loss and motor dysfunction is not straightforward. 

Examination of postmortem samples of human cerebella from neurologically typical individuals supports the presence of selective loss of Purkinje cells during aging.

These data reveal a spatiotemporal cellular substrate for aging in the cerebellum that may inform how neuronal vulnerability leads to neurodegeneration and the ensuing deterioration of behavior."

Aging Brains Show Stripes of Cell Death | The Scientist "Purkinje cells, the neurons of the cerebellum, appear to die in an organized pattern, overturning previous beliefs that neurodegeneration occurs homogeneously."

Cerebellar Purkinje cell stripe patterns reveal a differential vulnerability and resistance to cell loss during normal aging in mice (preprint, open access)

Figure 1: Wholemount immunohistochemistry of the cerebellum reveals striped Purkinje cell loss across the cerebellar cortex of some aged mice.