KCL study finds cell ageing could reveal early signs of neurodegenerative disease

Conditions such as Alzheimer’s and Parkinson’s affect over one million people in the UK

Researchers from King’s College London (KCL), along with other collaborators, have found that ageing cells could reveal early signs of neurodegenerative diseases, including Alzheimer’s disease or amyotrophic lateral sclerosis.

Published in Aging Cell, the findings could provide a wider picture of a target area for drugs and could improve treatments for these types of conditions.

Affecting more than one million people in the UK, neurodegenerative conditions, such as multiple sclerosis and Parkinson’s disease, occur when cells of the central nervous system stop working or die.

Using fluorescence to measure the viscosity of neuronal cytoplasm, the fluid enclosed by the cell membrane of the neuron, in mice, researchers found that the viscosity of the cytoplasm in the neuron (soma) increased as the mice aged. However, it did not increase in the cytoplasm of the axon, a tail-like structure that transmits electrical and chemical signals to other cells.

Researchers suggested that the mitochondria could not be exported from the cell body into the axons due to getting trapped in the viscous soma, impacting cell health.

Typically, during ageing and neurodegenerative illnesses, mitochondrial trafficking, where the parts of the cell responsible for making energy are transported from the central body of the soma to its axon, tends to decrease and is considered a litmus test for further degeneration in the brain.

When comparing cytoplasmic viscosity in healthy patients of similar ages, the team suggests that changing viscosity could potentially be used as a warning sign for neurodegenerative disease.

Study leading author Dr Alessio Vagnoni, lecturer in cellular neuroscience, KCL, commented: “By measuring viscosity in a model of neuronal ageing for the first time means we could also start mapping specific age-dependent neurodegenerative diseases to cytoplasmic viscosities and potentially expand the list of biomarkers for a range of illnesses.”

Researchers now plan to study how environmental factors like additional illnesses could impact the cytoplasm in the neuron during ageing and how it could lead to neurodegeneration.