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:UNLABELLED:Altered gut microbiome is associated with systemic inflammation and cirrhosis decompensation. However, the correlation of the oral microbiome with inflammation in cirrhosis is unclear. Our aim was to evaluate the oral microbiome in cirrhosis and compare with stool microbiome. Outpatients with cirrhosis (with/without hepatic encephalopathy [HE]) and controls underwent stool/saliva microbiome analysis (for composition and function) and also systemic inflammatory evaluation. Ninety-day liver-related hospitalizations were recorded. Salivary inflammation was studied using T helper 1 cytokines/secretory immunoglobulin A (IgA), histatins and lysozyme in a subsequent group. A total of 102 patients with cirrhosis (43 previous HE) and 32 age-matched controls were included. On principal component analysis (PCA), stool and saliva microbiome clustered far apart, showing differences between sites as a whole. In salivary microbiome, with previous HE, relative abundance of autochthonous families decreased whereas potentially pathogenic ones (Enterobacteriaceae, Enterococcaceae) increased in saliva. Endotoxin-related predicted functions were significantly higher in cirrhotic saliva. In stool microbiome, relative autochthonous taxa abundance reduced in previous HE, along with increased Enterobacteriaceae and Enterococcaceae. Cirrhotic stool microbiota demonstrated a significantly higher correlation with systemic inflammation, compared to saliva microbiota, on correlation networks. Thirty-eight patients were hospitalized within 90 days. Their salivary dysbiosis was significantly worse and predicted this outcome independent of cirrhosis severity. Salivary inflammation was studied in an additional 86 age-matched subjects (43 controls/43 patients with cirrhosis); significantly higher interleukin (IL)-6/IL-1?, secretory IgA, and lower lysozyme, and histatins 1 and 5 were found in patients with cirrhosis, compared to controls. CONCLUSIONS:Dysbiosis, represented by reduction in autochthonous bacteria, is present in both saliva and stool in patients with cirrhosis, compared to controls. Patients with cirrhosis have impaired salivary defenses and worse inflammation. Salivary dysbiosis was greater in patients with cirrhosis who developed 90-day hospitalizations. These findings could represent a global mucosal-immune interface change in cirrhosis.
Project description:Background and Aim: Liver cirrhosis is associated with decreased hepatic cytochrome P4503A (CYP3A) activity but the pathogenesis of this phenomenon is not well elucidated. In this study, we examined if certain microRNAs (miRNA) are associated with decreased hepatic CYP3A activity in cirrhosis. Hepatic CYP3A activity and miRNA microarray expression profiles were measured in cirrhotic (n=22) and normal (n=12) liver tissue. Hepatic CYP3A activity was measured via midazolam hydroxylation in human liver microsomes. Additionally, hepatic CYP3A4 protein concentration and the expression of CYP3A4 mRNA were measured. Analyses were conducted to identify miRNAs which were differentially expressed between two groups but also were significantly associated with lower hepatic CYP3A activity. Liver tissue was collected from individuals with established cirrhosis who were awaiting liver transplantation (n=22) at the time of their liver transplantation procedure in the operating room. Normal liver tissue (n=12) was obtained from patients undergoing liver resection for metastatic/benign liver lesions with no underlying chronic liver disease
Project description:Hepatic Encephalopathy is the brain disorder caused by liver damage, characterized by cognitive and motor impairments. Glutamate a predominant excitatory neurotransmitter over activate post-synaptic neuron via NMDAR receptors leads to neuronal derangement. NMDAR as a therapeutic target is not viable option due to its crucial role in brain physiology. In order to discover new non-NMDAR therapeutic targets high resolution mass spectrometry (HRMS) technique was used for proteomic profiling of the hippocampal proteins in Moderate hepatic encephalopathy (MoHE) rat model.
Project description:Hepatic encephalopathy (HE) is a common complication of liver cirrhosis, associated with high morbidity and mortality, for which no brain-targeted therapies exist at present. The interplay between hyperammonemia and inflammation is thought to drive HE development. As such, astrocytes, the most important ammonia-metabolizing cells in the brain, and microglia, the main immunomodulatory cells in the brain, have been heavily implicated in HE development. As insight into cellular perturbations driving brain pathology remains largely elusive, we aimed to investigate cell-type specific transcriptomic changes in the HE brain. In the recently established mouse bile duct ligation (BDL) model of HE, we performed RNA-Seq of sorted astrocytes and microglia at 14 and 28 days after induction. This revealed a marked transcriptional response in both cell types which was most pronounced in microglia. In both cell types, pathways related to inflammation and hypoxia, mechanisms commonly implicated in HE, were enriched. Additionally, astrocytes exhibited increased corticoid receptor and oxidative stress signaling, whereas microglial transcriptome changes were linked to immune cell attraction. Accordingly, both monocytes and neutrophils accumulated in the BDL mouse brain. Time-dependent changes were limited in both cell types, suggesting early establishment of a pathological phenotype. While HE is often considered a unique form of encephalopathy, astrocytic and microglial transcriptomes showed significant overlap with previously established gene expression signatures in other neuroinflammatory diseases like septic encephalopathy and stroke, suggesting common pathophysiological mechanisms. Our dataset identifies key molecular mechanisms involved in preclinical HE and provides a valuable resource for development of novel glial-directed therapeutic strategies.
Project description:Background and Aim: Liver cirrhosis is associated with decreased hepatic cytochrome P4503A (CYP3A) activity but the pathogenesis of this phenomenon is not well elucidated. In this study, we examined if certain microRNAs (miRNA) are associated with decreased hepatic CYP3A activity in cirrhosis. Hepatic CYP3A activity and miRNA microarray expression profiles were measured in cirrhotic (n=22) and normal (n=12) liver tissue. Hepatic CYP3A activity was measured via midazolam hydroxylation in human liver microsomes. Additionally, hepatic CYP3A4 protein concentration and the expression of CYP3A4 mRNA were measured. Analyses were conducted to identify miRNAs which were differentially expressed between two groups but also were significantly associated with lower hepatic CYP3A activity.
Project description:DNA methylation profile of mouse sperm from conventionally-raised mice and gut dysbiosis experienced mice were characterized using whole-genome bisulfite sequencing. Genome-wide DNA methylation changes between control and dysbiotic male�s sperm were highly comparable, with no change in DNAme globally or at genomic features, only 21 differentially methylated regions (DMR) were identified, which did not overlap known regulatory elements. Epididymal sperm samples were harvested from 11 weeks old inbred male mice that were experiencing gut microbiota dysbiosis for 6-week (antibiotics treated, n=5), or drink sterilized water (control, n=5).
Project description:Gut microbiota dysbiosis characterizes systemic metabolic alteration, yet its causality is debated. To address this issue, we transplanted antibiotic-free conventional wild-type mice with either dysbiotic (“obese”) or eubiotic (“lean”) gut microbiota and fed them either a NC or a 72%HFD. We report that, on NC, obese gut microbiota transplantation reduces hepatic gluconeogenesis with decreased hepatic PEPCK activity, compared to non-transplanted mice. Of note, this phenotype is blunted in conventional NOD2KO mice. By contrast, lean microbiota transplantation did not affect hepatic gluconeogenesis. In addition, obese microbiota transplantation changed both gut microbiota and microbiome of recipient mice. Interestingly, hepatic gluconeogenesis, PEPCK and G6Pase activity were reduced even once mice transplanted with the obese gut microbiota were fed a 72%HFD, together with reduced fed glycaemia and adiposity compared to non-transplanted mice. Notably, changes in gut microbiota and microbiome induced by the transplantation were still detectable on 72%HFD. Finally, we report that obese gut microbiota transplantation may impact on hepatic metabolism and even prevent HFD-increased hepatic gluconeogenesis. Our findings may provide a new vision of gut microbiota dysbiosis, useful for a better understanding of the aetiology of metabolic diseases. all livers are from NC-fed mice only.
Project description:The gut microbiota has an important role in the pathogenesis of hepatic encephalopathy(HE). Rifaximin, an intestinal non-absorbable antibacterial agent, is effective in the treatment of HE. However, whether long-term prophylactic use induces antibacterial resistance and its mechanism for treating HE remains unclear. This prospective study assessed the impact of 12 weeks rifaximin administration on the gut microbiota and resistome in cirrhotic patients. Fecal sampling was conducted 1 day before the first rifaximin administration and at Weeks 1, 2, 4, 6, 8, 10, 12 of the study. Thirty cirrhotic patients who were in remission from recurrent HE was enrolled to receive rifaximin (400mg TID for 12 weeks). Rifaximin improved hyperammonemia and cognitive function in the 21 patients who completed rifaximin treatment. The dynamic observations showed the gut microbiota diversity, composition and the number of resistance genes, plasmids, insertion sequences did not change significantly during the period(P>0.05). Metabolic pathways such as aromatic amino acids, tryptophan synthesis, urea cycle, and LPS synthesis reduced. No new antimicrobial resistance genes was emergenced. However, the number of aminoglycosides, rifamycin and phenolic resistance genes increased, whereas tetracycline, fosfomycin and cephamycin decreased (P<0.05). Changes in the abundance of E. coli, K. pneumoniae, and B. longum strains correlated with changes of resistance genes. Prophylactic use of rifaximin for 12 weeks improved hyperammonemia and neurophysiological function, maintained gut microbiota diversity, composition and did not change the overall resistome. Rifaximin altered expression of HE-related metabolic pathways. All of these effects could play a key role in preventing HE. Clinical Trial Registration: ChiCTR1900022234 (registered at the Chinese Clinical Trial Registry).