Hippocampal gene expression changes during age-related cognitive decline
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE13799 | GEO | 2009/01/15
SECONDARY ACCESSION(S): PRJNA110561
REPOSITORIES: GEO
Similar Datasets
Project description:Comparison of hippocampal gene expression between normal young animals and older animals with good spatial memory and older animals with poor spatial memory Experiment Overall Design: The hippocampus from animals with good spatial memory (unimpaired) were compared to animals with poor spartial memory (impaired)
2009-01-25 | E-GEOD-13799 | biostudies-arrayexpress
Project description:The current study employed next-generation RNA sequencing to examine gene expression related to brain aging and cognitive decline. Young and aged rats were trained on a spatial episodic memory task. Hippocampal regions CA1, CA3 and the dentate gyrus (DG) were isolated. Poly-A mRNA was examined using two different platforms, Illumina and Ion Proton. The Illumina platform was used to generate lists of genes that were differentially expressed across regions, ages, and in association with cognitive function. The gene lists were then retested using the Ion Proton platform. The results describe regional differences in gene expression and point to regional differences in vulnerability to aging. Aging was associated with increased expression of immune response related genes, particularly in the dentate gyrus. Finally, for the memory task used, impaired performance of aged animals was linked to the regulation of Ca2+ and synaptic function in region CA1.
2017-12-08 | GSE97608 | GEO
Project description:Aging is associated with low-grade chronic systemic inflammation. Elevated peripheral serum cytokines and chemokines contribute to age-related diseases and correlate with cognitive decline. This study compared the effects of repeated lipopolysaccharide (LPS) treatment in young rats to age-related changes in hippocampal-dependent cognition, synaptic transmission, and transcription. Young (5-7 months) Fischer 344 X Brown Norway hybrid rats were injected intraperitoneally once a week for 6-7 weeks with either LPS (1 mg/kg) or vehicle. Older (14-16 months) rats received a similar injection schedule of vehicle. Older-vehicle animals and young-LPS rats exhibited impaired retention of spatial memory. Examination of the transcriptome of the CA1 and the dentate gyrus indicated that older-vehicle and young-LPS animals exhibited an increase in immune response genes. In contrast to aging, young-LPS animals exhibited an increased expression of genes related to the synapse. Even though young-LPS animals increased the expression of synaptic genes, LPS treatment reduced hippocampal CA3-CA1 total synaptic response and N-methyl-D-aspartate receptor (NMDAR)-mediated component of the synaptic response. Interestingly, the decrease in NMDAR function was not redox-sensitive. This study demonstrates that repeated exposure to LPS has long-term effects on hippocampal synaptic transmission and memory; however, young animals exhibited transcriptional recovery after LPS treatment. Recovery likely results from the acute nature of repeated LPS injections, relative to chronic systemic inflammation observed during aging.
2020-11-30 | GSE140685 | GEO
Project description:Previous studies of age-related transcriptional changes indicate that cognitive impairments are associated with differentially expressed genes DEGs linked to defined neural systems; however, studies that examine multiple regions of the hippocampus fail to find major links between behavior and transcription in the dentate gyrus DG. The DG is implicated in pattern separation PS and exhibits multiple age-related changes that may affect PS performance. We hypothesize that an age-related decline in PS performance is associated with distinct changes in transcriptional profile, most strongly within the DG compared to other hippocampal subregions. We used a water maze beacon discrimination task to characterize PS in young 5 mo and middle-age 12 mo male F344 rats, followed by a spatial reference memory test. Middle-age rats showed consistent deficits in discriminating two identical beacons compared to young. Reference memory was not different between these two age groups. Interestingly, with increasing spatial overlap between the cues, older animals appeared to compensate for impaired PS performance though greater reliance on spatial reference memory. mRNA sequencing of hippocampal subregions DG, CA1, and CA3 indicated that the DG of middle-age rats expressed more genes correlated with PS performance. In contrast, reliance on a spatial reference memory was associated with differential expression of genes in regions CA1 and CA3. These results indicate that the beacon task is sensitive to PS impairment as early as middle-age, and distinct gene profiles are observed in neural circuits that underlie different strategies used to solve the task.
2020-05-22 | GSE140420 | GEO
Project description:Vitamin D is an important calcium-regulating hormone with diverse functions in numerous tissues including the brain. Increasing evidence suggests that vitamin D may play a role in maintaining cognitive function and that vitamin D deficiency may accelerate age-related cognitive decline. Using aging rodents, we attempted to model the range of human serum vitamin D levels, from deficient to sufficient, to test whether vitamin D could preserve or improve cognitive function with aging. For 5-6 months, middle-aged F344 rats were fed diets containing low, medium (typical amount) or high vitamin D3 (100, 1000 or 10,000 IU/kg diet, respectively) and then hippocampal-dependent learning and memory were tested in the Morris water maze. Rats on high vitamin D achieved the highest blood levels (in the sufficient range) and significantly outperformed low and medium groups on maze reversal, a particularly challenging task that detects more subtle changes in memory. In addition to calcium-related processes, hippocampal gene expression microarrays identified pathways pertaining to synaptic transmission, cell communication and G-protein function as being up-regulated with high vitamin D. Basal synaptic transmission also was enhanced corroborating observed effects on gene expression and learning and memory. Our studies demonstrate a causal relationship between vitamin D status and cognitive function and suggest that vitamin D-mediated changes in hippocampal gene expression may improve the likelihood of successful brain aging. Sixty, middle-aged male F344 rats were divided into three groups, each receiving for 5-6 months a different dietary amount of cholecalciferol (vitamin D3; VitD3). Purified AIN-93G (Harlan-Teklad) diet was modified to contain low, medium or high VitD3 (IU/kg diet): High = 10,000, Standard (Control) = 1000; Low = 100. Animal weight and amount of food consumed was recorded 2-3 times/week. Serum levels of 25-hydroxy vitamin D were determined using liquid chromatography/tandem mass spectrometry (ZRT Laboratory). Hippocampal RNA was isolated, quantified and checked for RNA integrity. One low VitD3 sample failed RNA quality control. Remaining RNA samples were applied to Affymetrix Rat Gene 1.0 ST arrays (one array/subject). Pre-statistical filtering removed poorly annotated probe sets, low intensity signals, and outlier values (>2SD of the group mean). Filtered data were analyzed by 1-way ANOVA to identify significant differences and the False Discovery Rate (FDR) procedure was used to estimate the error of multiple testing. FDR was compared at 0.31 and 0.17. Significant genes were assigned to one of four idealized expression patterns using Pearson’s test and separated by the sign of their correlation; relative gene expression values are provided on the log-2 scale. Functional categorization for significant genes was determined using DAVID bioinformatic tools. Please note that 'Marked' and 'Unmarked' (in the sample titles) refers to whether the rat had a mark on its tail. The rats were pair-housed and this is how two rats in one cage were distinguished.
2014-09-23 | E-GEOD-61326 | biostudies-arrayexpress
Project description:Calorie restriction (CR) enhances longevity and mitigates aging phenotypes in numerous species. Physiological responses to CR are cell-type specific and variable throughout the lifespan; however, the mosaic of molecular changes responsible CR benefits remain unclear, particularly in brain regions susceptible to deterioration throughout aging. Thus, we examined the influence of long-term CR on the CA1 hippocampal region, a key learning and memory brain area that is vulnerable to age-related pathologies, such as Alzheimerâs disease (AD). Through mRNA sequencing and NanoString nCounter analysis, we demonstrate that one year of CR feeding suppresses an age-dependent signature of 882 genes functionally associated with synaptic transmission-related pathways, including calcium signaling, long-term potentiation (LTP), and Creb signaling in wild-type mice. By comparing the influence of CR on hippocampal CA1 region transcriptional profiles at younger- (5 months) and older-adult (15 months) timepoints, we identify conserved upregulation of proteome quality control and calcium buffering genes, including heat shock 70 kDa proteins 1b and 5 (Hspa1b and Hspa5), protein disulfide isomerase family A members 4 and 6 (Pdia4 and Pdia6), and calreticulin (Calr). Expression levels of putative neuroprotective factors, klotho (Kl) and transthyretin (Ttr), are also elevated by CR throughout adulthood, although the global CR-specific expression profiles at young and older timepoints are highly divergent. At a previously unachieved resolution, our results demonstrate conserved activation of neuroprotective gene signatures and broad CR-suppression of age-dependent hippocampal CA1 region expression changes, indicating that CR functionally maintains a more youthful transcriptional state within hippocampal CA1 throughout aging. Hippocampal CA1 region mRNA profiles of younger- (5 months) and older-adult (15 months) mice on calorie-restricted (CR) and normal (AD) diets were generated by deep sequencing using Illumina HiSeq 2500.
2015-07-14 | E-GEOD-69952 | biostudies-arrayexpress
Project description:MicroRNAs (miRNA) are small, non-coding RNAs mediating post-transcriptional regulation of gene expression. miRNAs have recently been implicated in hippocampus-dependent functions such as learning and memory, although the roles of individual miRNAs in these processes remain largely unknown. Here, we achieved stable inhibition using AAV-delivered miRNA sponges of individual, highly expressed and brain-enriched miRNAs; miR-124, miR-9 and miR-34, in hippocampal neurons. Molecular and cognitive studies revealed a role for miR-124 in learning and memory. Inhibition of miR-124 resulted in an enhanced spatial learning and working memory capacity, potentially through altered levels of genes linked to synaptic plasticity and neuronal transmission. In contrast, inhibition of miR-9 or miR-34 led to a decreased capacity of spatial learning and of reference memory, respectively. On a molecular level, miR-9 inhibition resulted in altered expression of genes related to cell adhesion, endocytosis and cell death, while miR-34 inhibition caused transcriptome changes linked to neuroactive ligand-receptor transduction and cell communication. In summary, this study establishes distinct roles for individual miRNAs in hippocampal function. Three RNA samples containing bilateral entire hippocampi from three different mice, per group. Group 1 were injected with vector containing GFP and a miR34sp/miR9sp and the other group were subjected to a vector expressing GFP only.
2016-03-01 | E-GEOD-68884 | biostudies-arrayexpress
Project description:Vitamin D is an important calcium-regulating hormone with diverse functions in numerous tissues including the brain. Increasing evidence suggests that vitamin D may play a role in maintaining cognitive function and that vitamin D deficiency may accelerate age-related cognitive decline. Using aging rodents, we attempted to model the range of human serum vitamin D levels, from deficient to sufficient, to test whether vitamin D could preserve or improve cognitive function with aging. For 5-6 months, middle-aged F344 rats were fed diets containing low, medium (typical amount) or high vitamin D3 (100, 1000 or 10,000 IU/kg diet, respectively) and then hippocampal-dependent learning and memory were tested in the Morris water maze. Rats on high vitamin D achieved the highest blood levels (in the sufficient range) and significantly outperformed low and medium groups on maze reversal, a particularly challenging task that detects more subtle changes in memory. In addition to calcium-related processes, hippocampal gene expression microarrays identified pathways pertaining to synaptic transmission, cell communication and G-protein function as being up-regulated with high vitamin D. Basal synaptic transmission also was enhanced corroborating observed effects on gene expression and learning and memory. Our studies demonstrate a causal relationship between vitamin D status and cognitive function and suggest that vitamin D-mediated changes in hippocampal gene expression may improve the likelihood of successful brain aging.
2014-09-23 | GSE61326 | GEO
Project description:The study contained three groups of Sprague-Dawley male rats – two groups of aging animals (22-24 months) separated based on performance in spatial reference memory task; and the third, control group of young animals () not separated by behavioural testing. The synaptosome – enriched membrane fraction of the dentate gyrus was isolated from nine randomly chosen individuals per group and analysed by tandem mass tag (TMT) labelling and mass spectrometry (MS)-based quantitative proteomics. The proteomic experiment was performed in three TMT10plex sets, with each set containing samples from three biological replicates per group and one TMT 126 reference channel reserved to directly compare the protein intensities across the entire study. The peptides were analysed in two parallel MS runs representing two technical replicates per biological sample. The total number of 6513 protein entries was identified of which 471 showed a significantly changed level (p<0.05) in any of the three animal groups. The comparison between aged and young animals revealed 293 significantly changed proteins (p<0.05) in aged good performers vs young rats, and 310 significant proteins (p < 0.05) in aged bad performers vs young ones. The proteomic differences between aged good vs bad performers were represented by 78 significantly changed proteins (p < 0.05).
2019-08-19 | PXD013172 | Pride
Project description:Mice deficient in the glucocorticoid-regenerating enzyme 11β-HSD1 resist age-related spatial memory impairment. To investigate the mechanisms/pathways involved, we used microarrays to identify differentially expressed hippocampal genes that associate with cognitive ageing and 11β-HSD1. Aged wild-type mice were separated into memory-impaired and unimpaired relative to young controls according to their performance in the Y-maze. All individual aged 11β-HSD1-deficient mice showed intact spatial memory. The majority of differentially expressed hippocampal genes were increased with ageing (e.g. immune/inflammatory response genes) with no genotype differences. However, the neuronal-specific transcription factor, Npas4 and immediate early gene, Arc were reduced (relative to young) in the hippocampus of memory-impaired but not unimpaired aged wild-type or aged 11β-HSD1-deficient mice. Quantitative RT-PCR and in situ hybridization confirmed reduced Npas4 and Arc mRNA expression in memory-impaired aged wild-type mice. These findings suggest that 11β-HSD1 may contribute to the decline in Npas4 and Arc mRNA levels associated with memory impairment during ageing, and that decreased activity of synaptic plasticity pathways involving Npas4 and Arc may, in part, underlie the memory deficits seen in cognitively-impaired aged wild-type mice. 20 samples, 5 groups of 4 biological replicates each. Young, Wild Type animals are overall controls
2015-11-23 | E-GEOD-68515 | biostudies-arrayexpress