24Chronic social defeat stress is a cause in many cases of depression. In humans, chronic social stress is built over time based on our past social interaction, with numerous consequences on both a psychological and neurological level.
Beyond depression, many patients display cognitive disorders including memory and attention loss, and complicated decision-making. Current therapy is focused on treating depression, yet its impact on cognitive deficiency remains unclear.
Institut du Cerveau - ICM researchers focused on the behavioral and molecular impact of chronic social defeat stress in an experimental model summarizing similar symptoms to those observed in humans. They also studied the effect of a molecule named agomelatine that has demonstrated antidepressant and anxiolytic effects.
In addition to behavioral modifications and memory disorders observed in animals, researchers highlighted a decrease in the expression of certain genes of the hippocampus, an area of the brain that plays a crucial role in memory and known to be directly affected in social stress. Results showed that agomelatine has an effect on cognitive disorders and gene expression in the hippocampus.
This data suggests that agomelatine may be of particular interest in treating cognitive disorders associated with depression. Complementary studies will focus on studying the molecule’s mechanisms.
Sources
Effect of agomelatine on memory deficits and hippocampal gene expression induced by chronic social defeat stress in mice.
https://www.nature.com/articles/srep45907
Martin V, Allaïli N, Euvrard M, Marday T, Riffaud A, Franc B, Mocaër E, Gabriel C, Fossati P, Lehericy S, Lanfumey L. Sci Rep. 2017 Apr 4;8:45907