Synaptic Dysfunction in Huntington's Disease: Lessons from Genetic Animal Models

Area of Science:

• Neuroscience
• Neurodegenerative Diseases
• Genetics

Background:

• Huntington's disease (HD) involves progressive brain degeneration.
• Genetic animal models have advanced understanding of HD's functional and structural brain changes.
• Research is expanding beyond the striatum to the entire cortico-basal ganglia-cortical loop.

Purpose of the Study:

• To review and analyze current research on synaptic alterations in the brain of rodent models of Huntington's disease.
• To explore the role of cortical maldevelopment and mutant huntingtin protein interactions in synaptic dysfunction.
• To examine the progressive disconnection in the corticostriatal pathway and its impact on neuronal function and degeneration.

Main Methods:

• Review and analysis of existing studies on Huntington's disease rodent models.
• Focus on synaptic alterations in the cerebral cortex and basal ganglia.
• Examination of changes in glutamate and dopamine release in the striatum.

Main Results:

• Cortical maldevelopment contributes to corticostriatal pathway synaptic dysfunction.
• Mutant huntingtin protein interactions with synaptic proteins are implicated.
• Progressive corticostriatal disconnection engages extrasynaptic NMDA receptors, leading to cell degeneration.
• Biphasic changes in striatal glutamate and dopamine release correlate with disease stages.

Conclusions:

• Synaptic dysfunction in Huntington's disease is complex, involving cortical and striatal alterations.
• Understanding these synaptic changes offers insights into disease mechanisms and symptomatology.
• Therapeutic strategies targeting synaptic dysfunction are being explored.