# Neuronal hyperexcitability: A key to unraveling hippocampal synaptic dysfunction in Lafora disease

## TL;DR

This study explores how neuronal hyperexcitability contributes to synaptic dysfunction in Lafora disease using a mouse model and finds that early detection and treatment may help reverse some effects.

## Contribution

The study identifies early electrophysiological changes and demonstrates the therapeutic potential of cannabidiol in reversing synaptic dysfunction in Lafora disease.

## Key findings

- Epileptic-like activity in Epm2a R240X mice begins at 1 month and worsens with age.
- Aberrant long-term potentiation appears at 3 months and deteriorates by 12 months.
- Cannabidiol treatment reduces excitability and restores LTP in older mice.

## Abstract

Lafora disease (LD) is a rare progressive disorder caused by mutations in the EPM2A or EPM2B genes, characterized by the accumulation of Lafora bodies, drug‐resistant epilepsy, and cognitive decline. To investigate the early molecular mechanisms of LD, we studied electrophysiological changes in the dentate gyrus (DG) of the Epm2a

R240X
knock‐in mouse model at various ages.

Electrophysiological recordings measured neuronal membrane properties, epileptic‐like activity, epileptic thresholds, and synaptic plasticity in Epm2a

R240X
mice at 1, 3, and 12 months. We also employed Periodic Acid–Schiff (PAS) diastase staining, immunofluorescence, and Western blotting to detect Lafora bodies, amyloid beta deposition, and the expression of glutamate receptor subunits.

Epileptic‐like activity began at 1 month and intensified with age. Aberrant long‐term potentiation (LTP) appeared at 3 months and worsened by 12 months. Notably, cannabidiol treatment reduced excitability and restored LTP in older mice, suggesting its potential therapeutic value.

The reversibility of synaptopathy, even at advanced stages, reinforces the importance of early detection of hyperexcitability and the development of effective therapeutic approaches.