Voxel-based morphometry in the R6/2 transgenic mouse reveals differences between genotypes not seen with manual 2D...

Area of Science:

• Neuroscience
• Genetics
• Medical Imaging

Background:

• Huntington's disease (HD) is a fatal, inherited neurodegenerative disorder characterized by brain atrophy.
• The R6/2 mouse is a widely used model for studying HD.
• Traditional manual 2D morphometry may miss subtle neuropathological changes.

Purpose of the Study:

• To investigate brain structural differences in R6/2 mice using advanced MRI techniques.
• To evaluate the utility of voxel-based morphometry (VBM) for detecting HD-related brain changes.
• To correlate imaging findings with known behavioral deficits in HD models.

Main Methods:

• Ex vivo high-resolution, 3D magnetic resonance imaging (MRI) of 47 R6/2 transgenic and 42 wildtype (WT) mouse brains at 18 weeks.
• Automated voxel-based morphometry (VBM) analysis applied to MRI data.
• Comparison of VBM results with manual 2D morphometry.

Main Results:

• Significant differences in brain structures were identified between R6/2 mice and WT controls.
• Detected changes were predominantly bilateral, affecting the basal ganglia, hippocampus, cortex, hypothalamus, and cerebellum.
• VBM identified numerous changes not detectable by manual 2D morphometry, including heterogeneous striatal alterations.

Conclusions:

• Voxel-based morphometry is a sensitive technique for detecting developing neuropathology in HD mouse models.
• VBM can reveal subtle, widespread brain structural changes in R6/2 mice, including those in the striatum and cerebellum.
• This method holds promise for correlating sub-visual pathological changes with behavioral deficits in Huntington's disease research.