Anxiety-like features and spatial memory problems as a consequence of hippocampal SV2A expression

PLoS One. 2019 Jun 5;14(6):e0217882. doi: 10.1371/journal.pone.0217882. eCollection 2019.

Abstract

The Synaptic Vesicle Protein 2A (SV2A) is a transmembrane protein whose presence is reduced both in animal models and in patients with chronic epilepsy. Besides its implication in the epileptic process, the behavioural consequences of the changes in its expression remain unclear. The purpose of our research is to better understand the possible role(s) of this protein through the phenotype of cKO (Grik4 Cre+/-, SV2A lox/lox) mice, male and female, which present a specific decrease of SV2A expression levels in the hippocampal glutamatergic neurons but without any epileptic seizures. In this study, we compare the cKO mice with cHZ (Grik4 Cre+/-, SV2A lox/+) and WT (Grik4 Cre+/+, SV2A lox/lox) mice through a battery of tests, used to evaluate different features: the anxiety-related features (Elevated Plus Maze), the locomotor activity (Activity Chambers), the contextual fear-related memory (Contextual Fear Conditioning), and the spatial memory (Barnes Maze). Our results showed statistically significant differences in the habituation to a new environment, an increase in the anxiety levels and spatial memory deficit in the cHZ and cKO groups, compared to the WT group. No statistically significant differences due to the genotype appeared in the spontaneous locomotor activity or the fear-linked memory. However, sexual differences were observed in this last feature. These results highlight not only an important role of the SV2A protein in the cognitive and anxiety problems typically encountered in epileptic patients, but also a possible role in the symptomatology of other neurodegenerative diseases, such as the Alzheimer's disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anxiety / metabolism*
  • Anxiety / physiopathology*
  • Behavior, Animal
  • Conditioning, Classical
  • Fear
  • Female
  • Hippocampus / metabolism*
  • Male
  • Maze Learning
  • Membrane Glycoproteins / metabolism*
  • Memory Disorders / metabolism*
  • Memory Disorders / physiopathology*
  • Mice, Knockout
  • Motor Activity
  • Nerve Tissue Proteins / metabolism*
  • Spatial Memory*

Substances

  • Membrane Glycoproteins
  • Nerve Tissue Proteins
  • Sv2a protein, mouse

Grants and funding

This work has been supported by Action de Recherches Concertées (ARC, grant number 13/17-07) (AP, MES, OB, BR), la Communauté Française de Belgique (BR) and by the FNRS (BR). AP is research director from Fonds De La Recherche Scientifique -FNRS Belgium. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.