Project description:Vanishing white matter (VWM) is a leukodystrophy that primarily manifests in young children. In this disease, the brain white matter is differentially affected in a predictable pattern with telencephalic brain areas being more severely affected, while others remain allegedly completely spared. Using high-resolution mass spectrometry-based proteomics, we investigated the proteome patterns of the severely affected white matter in the frontal lobe and normal appearing pons in VWM and control cases to identify molecular bases underlying regional vulnerability. By comparing VWM patients to controls, we identified disease-specific proteome patterns. We showed substantial pathogenic changes in both the frontal white matter and pons at the protein level. Side-by-side comparison of brain region-specific proteome patterns further revealed regional differences. We found that different cell types are affected in the VWM frontal white matter than in the pons. Gene ontology and pathway analyses identified involvement of region distinct biological processes, of which pathways implicated in cellular respiratory metabolism were overarching features. In the VWM frontal white matter, proteome changes were associated with decrease in glycolysis/gluconeogenesis and metabolism of various amino acids. By contrast, in the VWM pons white matter, we found a decrease in oxidative phosphorylation. Taken together, our data show that brain regions are affected in parallel in VWM, but to different degrees. We found region-specific involvement of different cell types and discovered that cellular respiratory metabolism is differently affected across white matter regions in VWM. These region-specific changes help explain regional vulnerability to pathology in VWM.
Project description:Amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) (ALS/PDC) is a unique endemic neurodegenerative disease, with high-incidence foci in the Kii Peninsula, Japan. Although ALS/PDC presents with multiple proteinopathies, the genetic and environmental factors that influence disease onset remain unknown. We performed transcriptome analyses of patients’ brains, which may provide new insights into the pathomechanisms underlying Kii ALS/PDC. We prepared frozen brains from 3 healthy controls (frontal lobe and temporal lobe), 3 patients with Alzheimer’s disease (AD) (frontal lobe and temporal lobe) as tauopathy-disease controls, and 21 patients with Kii ALS/PDC (frontal lobe and/or temporal lobe). We acquired microarray data from the cerebral gray and white matter tissues of Kii ALS/PDC patients. Microarray data revealed that the expression levels of genes associated with neurons, heat shock proteins (Hsps), DNA binding/damage, and senescence were significantly changed in Kii ALS/PDC brains compared with those in control brains. The RNA expression pattern observed for Kii ALS type brains was similar to that for Kii PDC type brains and unlike those of control and AD brains. Additionally, pathway and network analyses indicated that the molecular pathogenic mechanism underlying Kii ALS/PDC may be associated with the oxidative phosphorylation of mitochondria, ribosomes, and the synaptic vesicle cycle; in particular, upstream regulators of these mechanisms may be found in synapses and during synaptic trafficking. Therefore, we propose the novel disease concept of “synaptopathy” for Kii ALS/PDC. Furthermore, phenotypic differences between Kii ALS type and Kii PDC type were observed, based on the human leukocyte antigen (HLA) haplotype. We performed exhaustive transcriptome analyses of Kii ALS/PDC brains, for the first time, and revealed new insights indicating that Kii ALS/PDC may be a synaptopathy. Determining the relationship between synaptic dysfunction and the pathogenesis of ALS/PDC may provide a new step toward understanding this mysterious disease.
Project description:We compared the gene expression in post-mortem brain specimen dissected from 2 CADASIL patients with samples from 5 non-affected controls in order to discover genes differentially expressed that could be involved in the development of neuronal damage in SVD. Samples form frontal cortex and white matter and occipital cortex and white matter were used.
Project description:The transcriptome of normal-appearing white matter for relapse-remitting multiple sclerosis (MS), primary progressive MS and secondary progressive MS was determined using total RNA-sequencing. We then performed a differential gene analysis comparing the normal-appearing white matter for each clinical subtype of MS with non-MS control tissue
Project description:Using the Illumina 450K array and a stringent statistical analysis with age and gender correction, we report genome-wide differences in DNA methylation between pathology-free regions derived from human multiple sclerosis–affected and control brains. Differences were subtle, but widespread and reproducible in an independent validation cohort. The transcriptional consequences of differential DNA methylation were further defined by genome-wide RNA-sequencing analysis and validated in two independent cohorts. Genes regulating oligodendrocyte survival, such as BCL2L2 and NDRG1, were hypermethylated and expressed at lower levels in multiple sclerosis–affected brains than in controls, while genes related to proteolytic processing (for example, LGMN, CTSZ) were hypomethylated and expressed at higher levels. These results were not due to differences in cellular composition between multiple sclerosis and controls. Thus, epigenomic changes in genes affecting oligodendrocyte susceptibility to damage are detected in pathology-free areas of multiple sclerosis–affected brains.
Project description:Genome-wide DNA methylation level was studied to determine whether multiple sclerosis patients (cases) has methylation differences comparing to normal controls in PBLs. We used Illumina HumanMethylation450 BeadChip array to determine the genome-wide DNA methylation difference in peripheral blood from multiple sclerosis patients (cases) and normal controls
Project description:Finding the differences in gene expression in three regions of the brain, basal ganglia, white matter, and frontal cortex, in normal, HIV infected, HIV infected with neurocognitive impairment, and HIV infected with both neurocognitive impairment and encephalitis patients.
Project description:Multiple sclerosis (MS) is a demyelinating disease of the central nervous system characterized by increased inflammation and immune responses, oxidative injury, mitochondrial dysfunction, and iron dyshomeostasis leading to demyelination and axonal damage. In MS, incomplete remyelination results in chronically demyelinated axons and degeneration coinciding with disability. This suggests a failure in the ability to remyelinate in MS, however, the precise underlying mechanisms remain unclear. We aimed to identify proteins whose expression was altered in chronic inactive white matter lesions and periplaque white matter in MS tissue to reveal potential pathogenic mechanisms. Laser capture microdissection coupled to proteomics was used to interrogate spatially preserved changes in formalin-fixed paraffin-embedded brain tissue from chronic MS individuals and controls with no apparent neurological complications. Histopathological maps guided the capture of inactive lesions, periplaque white matter, and cortex from chronic MS individuals along with corresponding white matter and cortex from control tissue. Label free quantitation by liquid chromatography tandem mass spectrometry was used to discover differentially expressed proteins between the various brain regions. In addition to confirming loss of several myelin-associated proteins known to be affected in MS, proteomics analysis of chronic inactive MS lesions revealed alterations in myelin assembly, metabolism, and cytoskeletal organization. Notably, a subset of proteins that were altered in MS white matter indicate altered lipid metabolism. Our findings highlight proteome changes in chronic inactive MS white matter lesions and periplaque white matter, which may be crucial for proper myelinogenesis, bioenergetics, focal adhesions, and cellular function. These findings highlight the importance and feasibility of spatial approaches such as laser capture microdissection-based proteomics analysis of pathologically distinct regions of MS brain tissue. Identification of spatially resolved changes in the proteome of MS brain tissue should aid in the understanding of pathophysiological mechanisms and the development of novel therapies.
Project description:Methylation state of human post-mortem brain tissue from the frontal lobe of patients with Frontotemporal Dementia caused by mutations in GRN, MAPT and C9orf72 and healthy controls
Project description:Microglia are brain-resident, myelin-phagocytosing cells, yet their role in lesion initiation in grey and white matter regions in multiple sclerosis (MS) is unclear. We isolated primary microglia from both, occipital cortex and corpus callosum, of 10 MS and 11 control donors and studied their transcriptional profile by RNA sequencing, thereby identifying regional and MS-associated changes. Identification of pathways underlying regional differences showed a relatively increased type I interferon response in cortical grey matter microglia, while white matter microglia more highly expressed NF-κB pathway genes. In normal-appearing white matter MS tissue, lipid metabolism genes were increased, suggesting processing of myelin by microglia already in areas seemingly devoid of MS pathology. Normal-appearing grey matter MS microglia showed increased activation of glycolysis and metal ion homeostasis, possibly reflecting microglia reacting to iron depositions. Notably, expression of genes associated with microglia homeostasis were hardly changed, suggesting that subtle regional changes in MS-associated microglia do not yet affect their resting state.