Project description:We characterize the meningeal leukocyte (CD45+ cells) in wild-type and 3xTg-AD mice, a transgenic model of Alzheimer's disease (AD).
Project description:The 3xTg-AD mouse is a widely used model in the study of Alzheimer’s Disease (AD). It has been extensively characterized both from the anatomical and behavioral point of view but poorly studied at the transcriptomic level. For the first time, this study characterizes the whole blood transcriptome of the 3xTg-AD mouse at three and six months of age and evaluates how gene expression is modulated by transcranial direct current stimulation (tDCS). RNA-seq analysis revealed 183 differentially expressed genes (DEGs) that were a direct signature of the genetic background of the mouse. The expression profile of age-related genes in the 3 months-old 3xTg-AD mice was more similar to that of 6 months rather than 3 months-control mice, suggesting a premature aging of the 3xTg-AD mice. Moreover, in the 6 months-old 3xTg-AD mice, we observed a high number of DEGs that could represent good peripheral biomarkers of AD progression. Finally, tDCS was associated with gene expression changes in the 3xTg-AD but not in the control mice. In conclusion, this study provides a better molecular characterization of the 3xTg-AD mouse and suggests that blood gene expression can be used to identify new biomarkers of AD progression and treatments effect.
Project description:We characterize the brain infiltrating leukocyte (CD45high cells) in wild-type and 3xTg-AD mice, a transgenic model of Alzheimer's disease (AD).
Project description:We characterize the brain infiltrating leukocyte (CD45high cells) in wild-type and 3xTg-AD mice, a transgenic model of Alzheimer's disease (AD).
Project description:Background: Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by memory impairment. Neuroinflammatory processes, mediated by glial and immune cells, contribute to neuronal damage. Emerging evidence implicates innate immune mechanisms, including trained immunity and cell trans-differentiation, in AD pathogenesis, though their roles remain unclear. Objective: To investigate transcriptomic changes in the 3xTg-AD mouse model, focusing on trained immunity and cell trans-differentiation in disease mechanisms. Methods: RNA-sequencing was performed on brain tissue (cortex plus hippocampus) from 11-month-old female 3xTg-AD and wild-type mice (n = 3/group). Differentially expressed genes (fold change > 1.5, p < 0.05) were identified and followed by bioinformatics and knowledge-based transcriptomic profiling. Public AD datasets were also analyzed. Results: 3xTg-AD mice exhibited 316 upregulated and 412 downregulated genes. Downregulated genes included those for blood-brain barrier protein, while upregulated genes related to cerebrospinal fluid. Increased expression of proinflammatory markers, as well as genes related to cell differentiation, proliferation, activation, and adhesion. Upregulation of genes associated with cell migration and trans-differentiation suggests a potential role for inflammation and cellular plasticity. Additionally, genes involved in inflammasome pathways, immunometabolism, and trained immunity were upregulated. Mechanistically, these genes were modulated by knockdown of trained immunity promoter SET-7, overexpression of trained immunity inhibitor IL-37, and knockout of inflammasome genes IL-1 receptor, caspase-1, and pattern recognition receptor CD36. Conclusions: The finding underscore the potential role of trained immunity and cell trans_x0002_differentiation in AD, revealing a mechanistic framework in which danger-associated molecular patterns drive innate immune responses, inflammasome activation, and cell plasticity contribute to AD, offering therapeutic targets for neuroinflammation and cellular reprograming.
Project description:ILC2 are potent producers of IL-5 and IL-13 and Th2 cytokines. We have found that 3xTg-AD mice exhibit diminished ILC2 numbers and functionality in the brain barriers. We have found through scRNA-seq that cultured brain ILC2 from 7 months old 3xTg-AD mice expressed significantly less IL-5 ane Areg but increased Gzma and Gzmb.
Project description:Adolescent sensitivity to alcohol is predictive of later alcohol use and is influenced by genetic background. Data from our laboratory suggested that adolescent C57BL/6J and DBA/2J inbred mice differed in susceptibility to dorsal hippocampus-dependent contextual fear learning deficits after acute alcohol exposure. To investigate the biological underpinnings of this strain difference, we examined dorsal hippocampus gene expression via RNA-sequencing after alcohol and/or fear conditioning across male and female C57BL/6J and DBA/2J adolescents. Strains exhibited dramatic differences in dorsal hippocampal gene expression. Specifically, C57BL/6J and DBA/2J strains differed in 3526 transcripts in males and 2675 transcripts in females. We identified pathways likely to be involved in mediating alcohol’s effects on learning, including networks associated with Chrna7 and Fmr1. These findings provide insight into the mechanisms underlying strain differences in alcohol’s effects on learning and suggest that different biological networks are recruited for learning based on genetics, sex, and alcohol exposure.
Project description:Alzheimer's disease (AD) patients exhibit neuropsychiatric symptoms that extend beyond classical cognitive deficits, suggesting involvement of subcortical areas. Here, we investigated the role of midbrain dopamine (DA) neurons in AD using the amyloid + tau-driven 3xTg-AD mouse model. We found deficits in reward-based operant learning in AD mice, suggesting possible VTA DA neuron dysregulation. Physiological assessment revealed hyperexcitability and disrupted firing in DA neurons caused by reduced activity of small-conductance calcium-activated potassium (SK) channels. RNA sequencing from contents of single patch-clamped DA neurons (Patch-seq) identified up-regulation of the SK channel modulator casein kinase 2 (CK2). Pharmacological inhibition of CK2 restored SK channel activity and normal firing patterns in 3xTg-AD mice. These findings shed light on a complex interplay between neuropsychiatric symptoms and subcortical circuits in AD, paving the way for novel treatment strategies.