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Neuronal loss, demyelination and volume change in the multiple sclerosis neocortex
D Carassiti1, D R Altmann2, N Petrova1
1Blizard Institute (Neuroscience), Queen Mary University of London, London, UK.
Neuropathology and Applied Neurobiology
|April 19, 2017
Summary
Multiple sclerosis (MS) causes massive neocortical neuronal loss, with brain volume decline potentially indicating neuron loss. Demyelination and neuronal loss appear independent in chronic MS.
Area of Science:
- Neuroscience
- Neuropathology
- Clinical Neurology
Background:
- Brain volume indices like grey matter, white matter (WM), and lesions are key outcomes in multiple sclerosis (MS) clinical trials.
- Understanding the relationship between brain structure and neuronal loss is crucial for MS research.
Purpose of the Study:
- To investigate the relationship between cortical volume, neocortical neuron number, and demyelination in multiple sclerosis (MS).
- To determine if in vivo detected cortical volume changes correlate with neuronal loss in MS patients.
Main Methods:
- Stereological principles and optical disectors were used to count neocortical neurons in dissected MS and control brain hemispheres.
- Grey and WM demyelination were quantified using myelin basic protein immunostaining.
Main Results:
- MS patients exhibited a 39% reduction in neocortical neurons compared to controls (P < 0.011).
- A strong association was found between the number of neurons and cortical volume (P < 0.0001).
- Demyelination in MS neocortex (40%) and WM (9%) did not correlate with neuronal loss.
Conclusions:
- Neocortical neuronal loss in MS is substantial and strongly predicted by cortical volume.
- In vivo cortical volume decline may reflect significant neuronal loss.
- Neuronal density and demyelination appear partially independent in chronic MS.
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