Project description:Gut microbiome research is rapidly moving towards the functional characterization of the microbiota by means of shotgun meta-omics. Here, we selected a cohort of healthy subjects from an indigenous and monitored Sardinian population to analyze their gut microbiota using both shotgun metagenomics and shotgun metaproteomics. We found a considerable divergence between genetic potential and functional activity of the human healthy gut microbiota, in spite of a quite comparable taxonomic structure revealed by the two approaches. Investigation of inter-individual variability of taxonomic features revealed Bacteroides and Akkermansia as remarkably conserved and variable in abundance within the population, respectively. Firmicutes-driven butyrogenesis (mainly due to Faecalibacterium spp.) was shown to be the functional activity with the higher expression rate and the lower inter-individual variability in the study cohort, highlighting the key importance of the biosynthesis of this microbial by-product for the gut homeostasis. The taxon-specific contribution to functional activities and metabolic tasks was also examined, giving insights into the peculiar role of several gut microbiota members in carbohydrate metabolism (including polysaccharide degradation, glycan transport, glycolysis and short-chain fatty acid production). In conclusion, our results provide useful indications regarding the main functions actively exerted by the gut microbiota members of a healthy human cohort, and support metaproteomics as a valuable approach to investigate the functional role of the gut microbiota in health and disease.
Project description:Secondary hyperparathyroidism is well known complication manifested in end-stage renal disease (ESRD). Both nodular and diffuse parathyreoid hyperplasia occur in ESRD patients. Distinct molecular mechanisms involved in parathyreoid hyperplasia remain poorly understood. Microarray screening proved homogeneity of gene transcripts in hemodialysis patients as compared to transplant cohort and primary hyperparathyreoidism, therefore further studies were performed in hemodialysis patints only. Enrichment analysis conducted on 485 differentially expressed genes between nodular and diffuse parathyreoid hyperplasia revealed highly significant differences in GO terms and KEGG database in ribosome structure (p=3.70-18). Next, RT-qPCR validation of microarray analysis proved higher expression of RAN guanine nucleotide release factor (RANGRF, p<0.001), calcyclin binding protein (CACYBP, p<0.05) and exocyst complex component 8 (EXOC8, p<0.05) and lower expression of peptidylprolyl cis/trans isomerase, NIMA-interacting 1 (PIN1, p<0.01) mRNA in nodular hyperplasia. Multivariate analysis revealed RANGRF and PIN1 expression along with parathyroid weight to be associated with nodular hyperplasia. Higher expression of genes associated with ribosomal structure and function underline extended translation mechanisms involved in parathyreoid nodular formation in long-term hemodialysis treated patients. Parathyroid tissue obtained from ESRD hyperparathyroidism patients who had undergone parathyroidectomy were used for transcriptome screening (Illumina HumanHT-12 v4.0 Expression BeadChips) and subsequently for discriminatory gene analysis, pathway mapping and gene-annotation enrichment analyses. Results were verified on enlarged group of hemodialysis patients with nodular (n=20) and diffuse (n=20) hyperplasia using RT-qPCR method.
Project description:Secondary hyperparathyroidism is well known complication manifested in end-stage renal disease (ESRD). Both nodular and diffuse parathyreoid hyperplasia occur in ESRD patients. Distinct molecular mechanisms involved in parathyreoid hyperplasia remain poorly understood. Microarray screening proved homogeneity of gene transcripts in hemodialysis patients as compared to transplant cohort and primary hyperparathyreoidism, therefore further studies were performed in hemodialysis patints only. Enrichment analysis conducted on 485 differentially expressed genes between nodular and diffuse parathyreoid hyperplasia revealed highly significant differences in GO terms and KEGG database in ribosome structure (p=3.70-18). Next, RT-qPCR validation of microarray analysis proved higher expression of RAN guanine nucleotide release factor (RANGRF, p<0.001), calcyclin binding protein (CACYBP, p<0.05) and exocyst complex component 8 (EXOC8, p<0.05) and lower expression of peptidylprolyl cis/trans isomerase, NIMA-interacting 1 (PIN1, p<0.01) mRNA in nodular hyperplasia. Multivariate analysis revealed RANGRF and PIN1 expression along with parathyroid weight to be associated with nodular hyperplasia. Higher expression of genes associated with ribosomal structure and function underline extended translation mechanisms involved in parathyreoid nodular formation in long-term hemodialysis treated patients.
Project description:This project contains raw data, intermediate files and results is a re-analysis of the publicly available dataset from the PRIDE dataset PXD005780. The RAW files were processed using ThermoRawFileParser, SearchGUI and PeptideShaker through standard settings (see ‘Data Processing Protocol’). This reanalysis work is part of the MetaPUF (MetaProteomics with Unknown Function) project, which is a collaboration between EMBL-EBI and the University of Luxembourg. The dataset was selected with the following conditions: 1. It has been made publicly available in PRIDE and focuses on metaproteomics of the human gut; 2. The corresponding metagenomics assemblies were also available from ENA (European Nucleotide Archive) or MGnify. The processed peptide reports for each sample are available to view at the contig level on the MGnify website. In total, the reanalysis identified 15,417 unique proteins from 15 samples.
Project description:Long-term dietary intake influences the structure and activity of the trillions of microorganisms residing in the human gut, but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundance of bile-tolerant microorganisms (Alistipes, Bilophila and Bacteroides) and decreased the levels of Firmicutes that metabolize dietary plant polysaccharides (Roseburia, Eubacterium rectale and Ruminococcus bromii). Microbial activity mirrored differences between herbivorous and carnivorous mammals, reflecting trade-offs between carbohydrate and protein fermentation. Foodborne microbes from both diets transiently colonized the gut, including bacteria, fungi and even viruses. Finally, increases in the abundance and activity of Bilophila wadsworthia on the animal-based diet support a link between dietary fat, bile acids and the outgrowth of microorganisms capable of triggering inflammatory bowel disease. In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles. RNA-Seq analysis of the human gut microbiome during consumption of a plant- or animal-based diet.
Project description:The gut microbiome plays an important role in normal immune function and has been implicated in several autoimmune disorders. Here we use high-throughput 16S rRNA sequencing to investigate the gut microbiome in subjects with multiple sclerosis (MS, n=61) and healthy controls (n=43). Alterations in the gut microbiome in MS include increases in the genera Methanobrevibacter and Akkermansia and decreases in Butyricimonas, and correlate with variations in the expression of genes involved in dendritic cell maturation, interferon signaling and NF-kB signaling pathways in circulating T cells and monocytes. Patients on disease-modifying treatment show increased abundances of the genera Prevotella and Sutterella, and decreased Sarcina, compared to untreated patients. MS patients of a second cohort show elevated breath methane compared to controls, consistent with our observation of increased gut Methanobrevibacter in MS in the first cohort. Further study is required to assess whether the observed alterations in the gut microbiome play a role in, or are a consequence of, MS pathogenesis.
Project description:Morphine and its pharmacological derivatives are the most prescribed analgesics for moderate to severe pain management. However, chronic use of morphine reduces pathogen clearance and induces bacterial translocation across the gut barrier. The enteric microbiome has been shown to play a critical role in the preservation of the mucosal barrier function and metabolic homeostasis. Here, we show for the first time, using bacterial 16s rDNA sequencing, that chronic morphine treatment significantly alters the gut microbial composition and induces preferential expansion of the gram-positive pathogenic and reduction of bile-deconjugating bacterial strains. A significant reduction in both primary and secondary bile acid levels was seen in the gut, but not in the liver with morphine treatment. Morphine induced microbial dysbiosis and gut barrier disruption was rescued by transplanting placebo-treated microbiota into morphine-treated animals, indicating that microbiome modulation could be exploited as a therapeutic strategy for patients using morphine for pain management. In this study, we establish a link between the two phenomena, namely gut barrier compromise and dysregulated bile acid metabolism. We show for the first time that morphine fosters significant gut microbial dysbiosis and disrupts cholesterol/bile acid metabolism. Changes in the gut microbial composition is strongly correlated to disruption in host inflammatory homeostasis13,14 and in many diseases (e.g. cancer/HIV infection), persistent inflammation is known to aid and promote the progression of the primary morbidity. We show here that chronic morphine, gut microbial dysbiosis, disruption of cholesterol/bile acid metabolism and gut inflammation; have a linear correlation. This opens up the prospect of devising minimally invasive adjunct treatment strategies involving microbiome and bile acid modulation and thus bringing down morphine-mediated inflammation in the host.