Dataset Information

Cortical axonal loss is associated with both gray matter demyelination and white matter tract pathology in progressive multiple sclerosis: Evidence from a combined MRI-histopathology study.

ABSTRACT:

Background

Neuroaxonal degeneration is one of the hallmarks of clinical deterioration in progressive multiple sclerosis (PMS).

Objective

To elucidate the association between neuroaxonal degeneration and both local cortical and connected white matter (WM) tract pathology in PMS.

Methods

Post-mortem in situ 3T magnetic resonance imaging (MRI) and cortical tissue blocks were collected from 16 PMS donors and 10 controls. Cortical neuroaxonal, myelin, and microglia densities were quantified histopathologically. From diffusion tensor MRI, fractional anisotropy, axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) were quantified in normal-appearing white matter (NAWM) and white matter lesions (WML) of WM tracts connected to dissected cortical regions. Between-group differences and within-group associations were investigated through linear mixed models.

Results

The PMS donors displayed significant axonal loss in both demyelinated and normal-appearing (NA) cortices (p?p?=?0.02) compared with controls. In PMS, cortical axonal density was associated with WML MD and AD (p?=?0.003; p?=?0.02, respectively), and NAWM MD and AD (p?=?0.04; p?=?0.049, respectively). NAWM AD and WML AD explained 12.6% and 22.6%, respectively, of axonal density variance in NA cortex. Additional axonal loss in demyelinated cortex was associated with cortical demyelination severity (p?=?0.002), explaining 34.4% of axonal loss variance.

Conclusion

Reduced integrity of connected WM tracts and cortical demyelination both contribute to cortical axonal loss in PMS.

SUBMITTER: Kiljan S

PROVIDER: S-EPMC7897796 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Cortical axonal loss is associated with both gray matter demyelination and white matter tract pathology in progressive multiple sclerosis: Evidence from a combined MRI-histopathology study.

Kiljan Svenja S Preziosa Paolo P Jonkman Laura E LE van de Berg Wilma Dj WD Twisk Jos J Pouwels Petra Jw PJ Schenk Geert J GJ Rocca Maria A MA Filippi Massimo M Geurts Jeroen Jg JJ Steenwijk Martijn D MD

Multiple sclerosis (Houndmills, Basingstoke, England) 20200511 3

<h4>Background</h4>Neuroaxonal degeneration is one of the hallmarks of clinical deterioration in progressive multiple sclerosis (PMS).<h4>Objective</h4>To elucidate the association between neuroaxonal degeneration and both local cortical and connected white matter (WM) tract pathology in PMS.<h4>Methods</h4><i>Post-mortem in situ</i> 3T magnetic resonance imaging (MRI) and cortical tissue blocks were collected from 16 PMS donors and 10 controls. Cortical neuroaxonal, myelin, and microglia densit ...[more]

PMID: 32390507

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Dataset Information

Cortical axonal loss is associated with both gray matter demyelination and white matter tract pathology in progressive multiple sclerosis: Evidence from a combined MRI-histopathology study.

Background

Objective

Methods

Results

Conclusion

Publications

Cortical axonal loss is associated with both gray matter demyelination and white matter tract pathology in progressive multiple sclerosis: Evidence from a combined MRI-histopathology study.

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