Neuropharmacology of Synaptic Vesicle Proteins in Epilepsy

Synaptic vesicle proteins, notably the synaptic vesicle glycoprotein family (SV2A, SV2B and SV2C), play a pivotal role in the regulation of neurotransmitter release and the modulation of neuronal excitability. In epilepsy, abnormal function or expression of these proteins can perturb the delicate balance between excitation and inhibition in neuronal circuits. SV2A in particular serves as the binding site for the anti-epileptic drug levetiracetam and its analogues, mediating effects on vesicle priming, calcium-dependent exocytosis and interaction with the calcium sensor synaptotagmin. Emerging modulators of SV2A and other vesicle proteins are being developed to refine seizure control, improve tolerability and target drug-resistant epilepsy. Advances in molecular genetics, electrophysiology and in vivo imaging have revealed how alterations in SV2A expression or function can facilitate kindling-dependent epileptogenesis and compromise GABAergic inhibition. Translational research now seeks to exploit these insights for precision pharmacotherapy, combining synaptic vesicle protein modulation with adjunctive targets such as the mTOR pathway and benzodiazepine sites to achieve durable seizure suppression and neuroprotection.

Research from Nature Portfolio

Recent studies have illustrated that a targeted missense mutation in SV2A markedly alters seizure susceptibility in a rodent kindling model. Animals carrying the L174Q substitution exhibit accelerated development of focal and generalised seizures, underpinned by a selective reduction of depolarisation-evoked GABA release in limbic regions. This dysfunction correlates with decreased levels of synaptotagmin 1, indicating that SV2A is essential for coupling calcium influx to inhibitory neurotransmitter exocytosis. The findings underscore the crucial role of the SV2A–GABA axis in modulating epileptogenic networks and validate SV2A as a genetic and pharmacological entry point for novel anti-epileptic strategies.

Neuropharmacology of Synaptic Vesicle Proteins in Epilepsy publication trend

The graph below shows the total number of articles in neuropharmacology of synaptic vesicle proteins in epilepsy across all publications each year (not limited to Nature Index journals).

Technical terms

Synaptic vesicle: Small, membrane-bound compartment in presynaptic terminals that stores neurotransmitters for regulated release.

SV2A: Synaptic vesicle glycoprotein 2A, a ubiquitous vesicle membrane protein essential for action potential-dependent neurotransmitter exocytosis and target of levetiracetam.

Kindling epileptogenesis: Progressive increase in seizure susceptibility induced by repeated subthreshold electrical or chemical stimuli, modelling chronic epilepsy.

GABAergic neurotransmission: Inhibitory neuronal signalling mediated by the release of gamma-aminobutyric acid and activation of GABA receptors.

mTOR pathway: Intracellular signalling network (mechanistic target of rapamycin) that regulates cell growth, metabolism and synaptic plasticity, implicated in seizure generation.

Positron emission tomography (PET): Functional imaging technique using radiolabelled tracers to visualise and quantify molecular targets, such as SV2A, in the living brain.

References

1. Changes in the Dentate Gyrus Gene Expression Profile Induced by Levetiracetam Treatment in Rats with Mesial Temporal Lobe Epilepsy. International Journal of Molecular Sciences (2024).
2. A Missense Mutation of the Gene Encoding Synaptic Vesicle Glycoprotein 2A (SV2A) Confers Seizure Susceptibility by Disrupting Amygdalar Synaptic GABA Release. Frontiers in Pharmacology (2016).
3. Levetiracetam Mechanisms of Action: From Molecules to Systems. Pharmaceuticals (2022).
4. Puzzling Out Synaptic Vesicle 2 Family Members Functions. Frontiers in Molecular Neuroscience (2017).
5. Synaptic Vesicle Glycoprotein 2A: Features and Functions. Frontiers in Neuroscience (2022).
6. SDI-118, a novel procognitive SV2A modulator: First-in-human randomized controlled trial including PET/fMRI assessment of target engagement. Frontiers in Pharmacology (2023).