Project description:Psychological, psychosocial and physical stress are major risk factors, which enhance the development of sporadic late-onset Alzheimer`s disease. The chronic unpredictable mild stress model mimics those risk factors and triggers signs of neurodegeneration and neuropathological features of sporadic AD such as tau hyperphosphorylation and enhanced amyloid beta generation. The study investigated the impact of chronic unpredictable mild stress on signs of neurodegeneration by analyzing hippocampal gene expression with whole genome microarray gene expression profiling.
Project description:Major depression is a multidimensional disorder highly prevalent in modern society. Although several classes of antidepressants (ADs) are currently available to treat depression, the effectiveness of treatment is still limited, as many patients do not show full remission; thus, there is a need to find better patients’ directed therapeutic strategies. Neuroplastic changes in several brain regions, namely in the hippocampal dentate gyrus (DG), are amongst the best correlates of depression and of ADs actions. In this study the targets and molecular mediators of chronic stress and of four ADs from different pharmacological classes (fluoxetine, imipramine, tianeptine and agomelatine) were investigated in the DG. Using the unpredictable chronic mild stress (uCMS) animal model of depression, the molecular commonalities and specificities of the ADs were determined. All ADs, except agomelatine, could reverse the behavioral deficits produced by uCMS, and the neuroplastic changes in the DG; agomelatine reversed only the anhedonic profile in the sucrose consumption test. Chronic stress induced mild but relevant molecular changes that were mostly reversed by fluoxetine, imipramine and tianeptine. Fluoxetine reduced pro-inflammatory response and increased cell metabolism pathways. Its actions were mostly dependent on molecular changes occurring in neurons. Similarities were found between imipramine and tianeptine molecular actions and targets, as both activated pathways related to cellular protection. Moreover, no particular neural cell type enrichment was found with both treatments. Agomelatine presented a very dissimilar molecular pattern impacting greatly on Rho-GTPases-related pathways in oligodendrocytes and neurons. The recognition of these molecular alterations contributes to the understanding of the processes implicated in the onset and treatment of depression and may pave the way for more effective therapeutic interventions. We compared gene expresssion in the dentate gyros of rats which were either untreated, exposed to unpredictable chronic mild stress, or exposed to the same stress and treated with either fluoxetine, imipramine, tianeptine, or agomelatine
Project description:Using a mouse model overexpressing human SNCA and profiling the striatal transcriptome, we assessed gene-environment interactions to reveal perturbations in gene expression and their modulation through chronic unpredictable mild stress (CUMS) exposure.
Project description:Using a mouse model overexpressing human SNCA and profiling the striatal transcriptome, we assessed gene-environment interactions to reveal perturbations in gene expression and their modulation through chronic unpredictable mild stress (CUMS) exposure.
Project description:In this study we employed the chronic unpredictable stress (CUS) rat model that leads to anxiety features comparable to humans and validated in several published reports as a well-characterized model of depression symptoms with high predictive validity. Cytokines and activated intracellular kinase levels were determined using high throughput multiplex assays. RNA from freshly isolated adipocytes was used to run whole genome expression microarray profiling in control and stressed rats. Adipocyte function was assessed via tritiated glucose uptake assay. The expression of four cytokines (TNFα, IL-1β, IL-6 and MCP-1) was validated via real-time PCR and the all showed increased expression levels with chronic unpredictable stress. Male rats were subjected to chronic unpredictable stress for 35 days and total body fat was measured. The analyses presented here represents data from experiments performed in 6 control and 6 stressed rats in parallel. All cells for RNA isolation were collected at the conclusion of the 35 day stress protocol.
Project description:Prenatal stress is one of the risk factors for the development of mental disorders in offspring, but its underlying mechanism remains elusive. To perform epigenomic profiling of prenatal stress effects on fetal brains, ATAC-seq and RNA-seq were used to explore the changes of chromatin accessibility and gene expression on embryonic brains at E15.5 of offspring from pregnant mice, which were exposed to chronic mild unpredictable stress between E5.5 to E14.5.
Project description:Major depressive disorder (MDD) is a severe psychiatric illness that affects about 16 percent of the global population. Despite massive efforts, unravelling the pathophysiology of MDD and developing effective treatments is still a huge challenge. Here, we report a novel therapeutic axis of methylglyoxal (MGO)/tropomyosin receptor kinase B (TrkB) for treating MDD. As an endogenous metabolite, MGO was demonstrated directly binding to the extracellular domain of TrkB, provoking its dimerization and autophosphorylation. This rapidly enhances the expression of brain-derived neurotrophic factor (BDNF) and forms a BDNF-positive feedback loop. Low-dose treatment of MGO effectively promotes the hippocampal neurogenesis and exhibits sustained antidepressant effects in chronic unpredictable mild stress rat models. In addition, the modulation on MGO concentration by overexpression or inhibition of Glyoxalase 1 (GLO1) has been demonstrated associated with depression behaviors in rats. Furthermore, we also identified a natural product luteolin and its derivative lutD as potent inhibitors of GLO1 and explored their precise binding modes. Our findings reveal a novel regulatory mechanism underlying MDD and depict principles for the rational design of new antidepressants targeting GLO1.
Project description:Female ICR mice were treated with stress or stress plus herbal medicine (KYZY decoction) in chronic unpredictable mild stress (CUMS) model. Fifteen isolated oocytes from each mouse were used for RNA-seq analysis. We used DESeq2 to identify differentially expressed genes (DEGs) between groups. DAVID and GO resources were used to perform gene enrichment analysis on the DEGs.