Project description:Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder that is clinically defined in terms of motor symptoms. These are preceded by prodromal non-motor manifestations that prove the systemic nature of the disease. Identifying genes and pathways altered in living patients provide new information on the diagnosis and pathogenesis of sporadic PD. We study changes in gene expression in the blood of 40 sporadic PD patients and 20 healthy controls (Discovery set?) by taking advantage of the Affymetrix platform. Patients were at the onset of motor symptoms and before initiating any pharmacological treatment. By applying Ranking-Principal Component Analysis, PUMA and Significance Analysis of Microarrays, gene expression profiling discriminates patients from healthy controls and identifies differentially expressed genes in blood. The majority of these are also present in dopaminergic neurons of the Substantia Nigra, the key site of neurodegeneration. Together with neuronal apoptosis, lymphocyte activation and mitochondrial dysfunction, already found in previous analysis of PD blood and post-mortem brains, we unveiled transcriptome changes enriched in biological terms related to epigenetic modifications including chromatin remodeling and methylation. Candidate transcripts were validated by RT-qPCR in an independent cohort of 12 patients and controls (?Validation set). Our data support the use of blood transcriptomics to study neurodegenerative diseases. It identifies changes in crucial components of chromatin remodeling and methylation machineries as early events in sporadic PD suggesting epigenetics as target for therapeutic intervention. Analyzed samples include blood samples from 40 PD patients and 20 healthy controls. Of the original 60 samples, one (a control sample) did not pass the microarray hybridization quality controls and was excluded from further analyses. All results of bioinformatics analyses shown in this study refer to this set of 59 samples (reported here).
Project description:Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder that is clinically defined in terms of motor symptoms. These are preceded by prodromal non-motor manifestations that prove the systemic nature of the disease. Identifying genes and pathways altered in living patients provide new information on the diagnosis and pathogenesis of sporadic PD. We study changes in gene expression in the blood of 40 sporadic PD patients and 20 healthy controls (“Discovery set”) by taking advantage of the Affymetrix platform. Patients were at the onset of motor symptoms and before initiating any pharmacological treatment. By applying Ranking-Principal Component Analysis, PUMA and Significance Analysis of Microarrays, gene expression profiling discriminates patients from healthy controls and identifies differentially expressed genes in blood. The majority of these are also present in dopaminergic neurons of the Substantia Nigra, the key site of neurodegeneration. Together with neuronal apoptosis, lymphocyte activation and mitochondrial dysfunction, already found in previous analysis of PD blood and post-mortem brains, we unveiled transcriptome changes enriched in biological terms related to epigenetic modifications including chromatin remodeling and methylation. Candidate transcripts were validated by RT-qPCR in an independent cohort of 12 patients and controls (“Validation set”). Our data support the use of blood transcriptomics to study neurodegenerative diseases. It identifies changes in crucial components of chromatin remodeling and methylation machineries as early events in sporadic PD suggesting epigenetics as target for therapeutic intervention.
Project description:Peripheral blood was collected from 18 Parkinson's Disease (PD) patients and 12 healthy controls (Ctrls). Total RNA was isolated and hybridized onto Affymetrix Exon_ST1 arrays to find in PDs versus controls: 1) genes that are differentiallly expressed and 2) genes with differential exonic expression (alternative splicing).
Project description:Genome-wide profiling of DNA methylation in blood leukocytes from Chinese patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD). The Illumina Infinium MethylationEPIC BeadChip array (850K chip) was used to detect DNA methylation profiles throughout approximately 850,000 CpG sites in peripheral blood white cells of MCI- and AD-affected Chinese patients, as well as cognitively healthy controls. All samples included 20 Chinese patients with MCI, 20 Chinese patients with AD, and 20 cognitively healthy controls.
Project description:Gabriela Novak et al. utilize scRNA-seq to investigate expression profiles in iPSC-derived midbrain dopaminergic neurons from Parkinson's disease patients or healthy controls. Their results suggest a core molecular network associated with Parkinson's disease pathology, and provide a future resource for investigation of this critical disorder.
Project description:The molecular mechanism underlying Parkinson's disease (PD), an increasingly common neurodegenerative disease, remains unclear. Long non-coding RNA (lncRNA) plays essential roles in gene expression and human disease. We hypothesize that lncRNAs are involved in the pathogenesis of PD. We profiled the expression of lncRNA in circulating leukocytes of 5 PD patients and 5 healthy controls using microarray.
Project description:We measured the isoaspartate levels in human serum albumin of blood samples from 20 patients with Alzheimer's disease and 20 healthy controls.
Project description:Amyotrophic lateral sclerosis is a clinical syndrome with complex biological determinants, but which in most cases is characterised by TDP-43 pathology. The identification in CSF of a protein signature of TDP-43 network dysfunction would have the potential to inform the identification of new biomarkers and therapeutic targets. We compared CSF proteomic data from patients with ALS (n=41), Parkinson's disease (n=19) and healthy control participants (n=20). Weighted correlation network analysis was used to identify modules within the CSF protein network and combined with gene ontology enrichment analysis to functionally annotate module proteins. Analysis of module eigenproteins and differential correlation analysis of the CSF protein network was used to compare ALS and Parkinson's disease protein co-correlation with healthy controls. In order to monitor temporal changes in the CSF proteome, we performed longitudinal analysis of the CSF proteome in a subset of ALS patients. Alterations in the co-correlation network in CSF samples identified a set of pathways known to be associated with TDP-43 dysfunction in the pathogenesis of ALS, with important implications for therapeutic targeting and biomarker development.
Project description:Parkinson's disease (PD) progresses relentlessly and affects five million people worldwide. Laboratory tests for PD are critically needed for developing treatments designed to slow or prevent progression of the disease. We performed a transcriptome-wide scan in 105 individuals to interrogate the molecular processes perturbed in cellular blood of patients with early-stage PD. The molecular marker here identified is strongly associated with risk of PD in 66 samples of the training set (third tertile cross-validated odds ratio of 5.7 {P for trend 0.005}). It is further validated in 39 independent test samples (third tertile odds ratio of 5.1 {P for trend 0.04}). The genes differentially expressed in patients with PD, or Alzheimer's or progressive supranuclear palsy offer unique insights into disease-linked processes detectable in peripheral blood. Combining gene expression scans in blood and linked clinical data will facilitate the rapid characterization of candidate biomarkers as demonstrated here with respect to PD. Experiment Overall Design: Whole blood expression data from 50 patients with Parkinson's disease, 33 with neurodegenerative diseases other than PD, and 23 healthy controls.