LPM570065 ameliorates anxiety-like and depressive-like behaviors in CUMS rats through regulating DNA methylation in hippocampus

Abstract

Objective: In this study, we aimed to analyze the effects and underlying mechanisms of LPM570065 on behavioral phenotypes in rats with generalized anxiety disorder (GAD).Methods: The chronic unpredictable mild stress (CUMS) rats were used to observe the results of LPM570065. Total 72 male Sprague Dawley rats were divided into control, vehicle (0.5% CMC-Na), LPM570065 (32 mg/kg) and diazepam (3 mg/kg) groups, 12 rats in each group. Anxiety-like behaviors of rats were observed by elevated zero maze test and novelty-suppressed feeding test. Depressive-like behaviors of rats were detected by forced swimming test. DNA methylation in hippocampi of rats were measured by reduced representation bisulfite sequencing (RRBS). In hippocampi of rats, expressions of DNA methyltransferase (DNMT) 1 and DNMT3a proteins were measured by western blot, and density of dendritic spines was observed by Golgi staining.Results: Compared with the control group, the weights of rats were obviously decreased (p < 0.001) and the rats showed anxiety-like and depressive-like behaviors (p < 0.001) in the vehicle group. Compared with the vehicle group, the weights of rats were significantly increased (p < 0.001) and the anxiety-like and depressive-like behaviors were improved (p < 0.001) in the LPM570065 group. The results of RRBS showed that there were 49964 promoters showed hypermethylation in the LPM570065 treatment rats contrasted to the vehicle treatment rats. In addition, these promoters were enriched in signal transduction and immune function. Furthermore, the expressions of DNMT1 and DNMT3a were significantly decreased, the density of dendritic spines was significantly increased in hippocampi of LPM570065 treatment rats compared with the vehicle treatment rats.Conclusions: LPM570065 ameliorates anxiety-like and depressive-like behaviors in CUMS rats, and its mechanism is possible associated with downregulating DNA methylation in hippocampus.