Project description:Hepatic encephalopathy (HE) is a frequent complication of liver cirrhosis and is seen as the clinical manifestation of a low grade cerebral edema associated with oxidative-nitrosative stress, however, comprehensive data on HE-associated molecular derangements in human brain are lacking. In the present study we used a whole human genome micro-array approach for gene expression profiling in post mortem brain samples from cirrhotic patients with or without HE and non-cirrhotic controls. Altered expression levels were found for a total of 1012 genes in liver cirrhotic patients without and with HE and HE-characteristic gene expression changes were identified. Genes with altered expression pattern in HE were related oxidative stress, microglia activation, inflammatory signalling pathways, cellular proliferation and apoptosis. Despite an up-regulation of genes associated with microglia activation, pro-inflammatory cytokine mRNA profiles remained unchanged in the brain of patients with liver cirrhosis and HE as compared to controls. Interestingly, many genes counteracting pro-inflammatory signalling and inflammatory cytokine expression were up-regulated in the cerebral cortex of patients with liver cirrhosis and HE. It is concluded that pathogenetic mechanisms of HE deduced from cell culture and animal experiments, such as oxidative stress, altered Zn2+-homeostasis and microglia activation also apply to human brain from cirrhotic patients with HE. The study also revealed a not yet recognized increased expression of genes antagonizing pro-inflammatory signalling and inflammatory cytokine expression. The dataset comprises 19 samples divided into three sample groups each representing a certain liver disease condition of humans.
Project description:Hepatic encephalopathy (HE) is a frequent complication of liver cirrhosis and is seen as the clinical manifestation of a low grade cerebral edema associated with oxidative-nitrosative stress, however, comprehensive data on HE-associated molecular derangements in human brain are lacking. In the present study we used a whole human genome micro-array approach for gene expression profiling in post mortem brain samples from cirrhotic patients with or without HE and non-cirrhotic controls. Altered expression levels were found for a total of 1012 genes in liver cirrhotic patients without and with HE and HE-characteristic gene expression changes were identified. Genes with altered expression pattern in HE were related oxidative stress, microglia activation, inflammatory signalling pathways, cellular proliferation and apoptosis. Despite an up-regulation of genes associated with microglia activation, pro-inflammatory cytokine mRNA profiles remained unchanged in the brain of patients with liver cirrhosis and HE as compared to controls. Interestingly, many genes counteracting pro-inflammatory signalling and inflammatory cytokine expression were up-regulated in the cerebral cortex of patients with liver cirrhosis and HE. It is concluded that pathogenetic mechanisms of HE deduced from cell culture and animal experiments, such as oxidative stress, altered Zn2+-homeostasis and microglia activation also apply to human brain from cirrhotic patients with HE. The study also revealed a not yet recognized increased expression of genes antagonizing pro-inflammatory signalling and inflammatory cytokine expression.
Project description:Patients with liver cirrhosis may develop minimal hepatic encephalopathy (MHE) which affects their quality of life and life span. It has been proposed that a shift in peripheral inflammation triggers the appearance of MHE. However, the mechanisms involved in this immune system shift remain unknown. In this work we studied the broad molecular changes involved in the induction of MHE with the goal of identifying (1) altered genes and pathways in peripheral blood cells associated to the appearance of MHE, (2) serum metabolites and cytokines with modified levels in MHE patients and (3) MHE-regulated immune response processes related to changes in specific serum molecules. We adopted a multi-omic approach to profile the transcriptome, metabolome and a panel of cytokines of blood samples taken from cirrhotic patients with or without MHE.
Project description:Patients with liver cirrhosis may have minimal hepatic encephalopathy (MHE) with cognitive and motor impairments that reduce life quality and span. MHE onset is associated with a shift in peripheral inflammation in which CD4+ lymphocytes play a key role but the underlying mechanisms remain unclear. We aimed to identify in CD4+ lymphocytes from patients with and without MHE: (1) gene expression changes and associated biological pathways using RNA-seq; (2) alterations in miRNA levels using miRNA-seq; (3) miRNAs and transcription factors regulating key mRNAs and (4) signalling pathways contributing to the peripheral inflammation shift associated to MHE onset. Additionally, we recovered T-cell receptor (TCR) repertoires from RNA-seq dataset to understand the immune status of control patients and cirrhotic patients with or without MHE.
Project description:In this study, we performed the first genome-wide expression profiling of post-mortem brains of a cohort of patients deceased from SVD and compared them to age-matched normal controls. Normal-appearing frontal temporal and occipital cortical and subcortical brain samples were dissected at autopsy from 5 patients diagnosed with pure SVD and 5 control patients without neurological disease and immediately frozen.
Project description:CpG methylation analysis of MeDIP DNA using Agilent Human DNA methylation Microarray slides (G4495A, AMADID 023795) Using methylated DNA immunoprecipitation microarray (MeDIP-chip) and Agilent Human DNA methylation Microarray slides (G4495A, AMADID 023795) we report genomic methylation signatures of tissues resected from Mesial temporal epilepsy (MTLE) and Focal cortical dysplasia (FCD) type II patients undergoing surgery. Control samples were obtained from the non-epileptic post mortem cases without any brain pathology
Project description:We analyzed fresh frozen post-mortem brain tissue from a cohort of 73 schizophrenic and 52 control samples, using the Illumina Infinium HumanMethylation450 Bead Chip, to investigate genome-wide DNA methylation patterns in patients diagnosed with schizophrenia.
2019-03-21 | GSE128601 | GEO
Project description:miRNA-Seq study of post-mortem Alzheimer's Disease brain samples
Project description:Chronic alcohol consumption can lead to alchohol-related brain damage (ARBD). Despite the well known acute effects of alcohol the mechanism responsible for chronic brain damage is largely unknown. Pathologically the major change is the loss of white matter while neuronal loss is mild and restricted to a few areas such as the prefrontal cortex. In order to improve our understanding of ARBD pathogenesis we used microarrays to explore the white matter transcriptome of alcoholics and controls. Our results suggest that hepatic encephalopathy, along with two confounders, gray matter contamination and low RNA quality, are major drivers of gene expression in ARBD. All three exceeded the effects of alcohol itself. In particular, low quality RNA samples were characterized by an upregulation of protein translation machinery while hepatic encephalopathy was associated with a downregulation of mitochondrial energy metabolism pathways. The findings in HE alcoholics are consistent with the metabolic acidosis seen in this condition. In contrast non-HE alcoholics had widespread but only subtle changes in gene expression in their white matter. The initial cohort was compromised of four alcoholics without hepatic encephalopathy (non-HE alcoholics), three alcoholics with HE (HE alcoholics) and three neurologically normal controls. For each indvidual frozen white matter was sampled in the superior frontal gyrus (prefrontal cortex) and the precentral gyrus (motor cortex). These two cortices experience either moderate (prefrontal cortex) or no neuronal loss (motor cortex) with alcohol-related brain damage. Each white matter sample was divided in two before RNA was extracted to give two 'biological' repeats and a total of 40 samples. Subsequently eight duplicates were removed due to their gray matter contamination or low RNA quality to leave a 32-sample cohort (23 alcoholic (including eight with HE ) and nine control samples.