Project description:Layer II stellate neurons (entorhinal cortex) and layer III cortical neurons (hippocampus CA1, middle temporal gyrus, posterior cingulate, superior frontal gyrus, primary visual cortex) were gene expression profiled. Brain regions are from non-demented individuals with intermediate Alzheimer's disease neuropathologies Keywords: neuronal gene expression profiling
Project description:Dissecting the shared etiology of different diseases could benefit from a systematic search for associated molecules and their interactions. We investigated genome-wide disruptions in the co-regulation of genes in two neurodegenerative diseases, Alzheimer's or Huntington's disease (AD or HD), using expression profiles from postmortem prefrontal cortex samples of 624 demented patients and non-demented control individuals with matched genotype and clinical data. A meta-analysis based screen for changes in coordinate expression patterns revealed differentially co-expressed (DC) gene pairs that either gained or lost correlation in disease cases relative to the control group, with the former being dominant for both AD and HD. Integration of disruptions common to AD and HD with large-scale data on protein-protein and protein-DNA interactions yielded a 242-gene sub-network that was enriched for proteins involved in neuronal differentiation and genetic associations to brain structural changes and dementia in subjects aged over 70 years. Replication of the AD DC network in independent human and mouse cohorts lends confidence to the comprehensive view we offer on dysregulated brain molecular pathways in AD and HD. DLPFC (BA9) brain tissues of AD patients, HD patients and non-demented controls samples were obtained from Harvard Brain tissue resource center (HBTRC). The HBTRC samples were primarily of Caucasian ancestry, as only eight non-Caucasian outliers were identified, and therefore excluded for further analysis. Post-mortem interval (PMI) was 17.8+8.3 hours (mean ± standard deviation), sample pH was 6.4±0.3 and RNA integrity number (RIN) was 6.8±0.8 for the average sample in the overall cohort. Tissues were profiled on a custom-made Agilent 44K array (GPL4372). 624 individual DLPFC samples were profiled against a common DLPFC pool constructed from the same set of samples.
Project description:Alzheimer's Disease (AD) and Non-Demented Control (NDC) human sera were probed onto human protein microarrays in order to identify differentially expressed autoantibody biomarkers that could be used as diagnostic indicators.
Project description:Dissecting the shared etiology of different diseases could benefit from a systematic search for associated molecules and their interactions. We investigated genome-wide disruptions in the co-regulation of genes in two neurodegenerative diseases, Alzheimer's or Huntington's disease (AD or HD), using expression profiles from postmortem prefrontal cortex samples of 624 demented patients and non-demented control individuals with matched genotype and clinical data. A meta-analysis based screen for changes in coordinate expression patterns revealed differentially co-expressed (DC) gene pairs that either gained or lost correlation in disease cases relative to the control group, with the former being dominant for both AD and HD. Integration of disruptions common to AD and HD with large-scale data on protein-protein and protein-DNA interactions yielded a 242-gene sub-network that was enriched for proteins involved in neuronal differentiation and genetic associations to brain structural changes and dementia in subjects aged over 70 years. Replication of the AD DC network in independent human and mouse cohorts lends confidence to the comprehensive view we offer on dysregulated brain molecular pathways in AD and HD.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Gene expression profiling was performed on frontal and temporal cortex from vascular dementia (VaD), Alzheimer's disease (AD), and non-demented controls (Control) obtained from the University of Michigan Brain Bank. Controls and AD cases had no infarcts in the autopsied hemisphere. Vascular dementia cases had low Braak staging.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:Recent work has identified roles for environmental, genetic and epigenetic factors in AD risk. Motivated by suspected roles for epigenetic modifications in AD, we performed a genome-wide screen of DNA methylation using the Illumina Infinium HumanMethylation450 array platform on bulk tissue samples from the superior temporal gyrus (STG) of AD cases and non-demented controls. We paired a sliding window approach with linear models that account for age, gender, ethnicity, and estimated cellular proportions (neuronal vs. glial), to characterize AD-associated differentially methylated regions (DMRs). Whole DNA was extracted from STG tissue dissections collected from deceased individuals with and without Alzheimers Disease. DNA was bisulfite converted and global DNA methylation levels were assessed using Illumina Infinium HumanMethylation450 BeadChip.