scholarly journals The effect of bile acids on the growth and global gene expression profiles in Akkermansia muciniphila

2020 ◽  
Vol 104 (24) ◽  
pp. 10641-10653
Author(s):  
Tatsuro Hagi ◽  
Sharon Y. Geerlings ◽  
Bart Nijsse ◽  
Clara Belzer
Keyword(s):  
Gene Expression ◽  
Bile Acids ◽  
Bile Salts ◽  
Membrane Structure ◽  
Expression Profiles ◽  
Membrane Damage ◽  
Sodium Deoxycholate ◽  
Gene Clusters ◽  
Bile Tolerance ◽  
Akkermansia Muciniphila

Abstract Akkermansia muciniphila is a prominent member of the gut microbiota and the organism gets exposed to bile acids within this niche. Several gut bacteria have bile response genes to metabolize bile acids or an ability to change their membrane structure to prevent membrane damage from bile acids. To understand the response to bile acids and how A. muciniphila can persist in the gut, we studied the effect of bile acids and individual bile salts on growth. In addition, the change in gene expression under ox-bile condition was studied. The growth of A. muciniphila was inhibited by ox-bile and the bile salts mixture. Individual bile salts have differential effects on the growth. Although most bile salts inhibited the growth of A. muciniphila, an increased growth was observed under culture conditions with sodium deoxycholate. Zaragozic acid A, which is a squalene synthase inhibitor leading to changes in the membrane structure, increased the susceptibility of A. muciniphila to bile acids. Transcriptome analysis showed that gene clusters associated with an ABC transporter and RND transporter were upregulated in the presence of ox-bile. In contrast, a gene cluster containing a potassium transporter was downregulated. Membrane transporter inhibitors also decreased the tolerance to bile acids of A. muciniphila. Our results indicated that membrane transporters and the squalene-associated membrane structure could be major bile response systems required for bile tolerance in A. muciniphila. Key points • The growth of Akkermansia muciniphila was inhibited by most bile salts. • Sodium deoxycholate increased the growth of A. muciniphila. • The genes encoding transporters and hopanoid synthesis were upregulated by ox-bile. • The inhibitors of transporters and hopanoid synthesis reduced ox-bile tolerance.

scholarly journals Application of Gene Shaving and Mixture Models to Cluster Microarray Gene Expression Data

2007 ◽  
Vol 5 ◽  
pp. 117693510700500
Author(s):  
K-A. Do ◽  
G.J. McLachlan ◽  
R. Bean ◽  
S. Wen
Keyword(s):  
Gene Expression ◽  
Expression Profiles ◽  
Lymphoblastic Leukemia ◽  
Gene Clusters ◽  
Gene Clustering ◽  
Expression Data ◽  
Colon Tissue ◽  
Data Set ◽  
Tissue Samples ◽  
Gene Shaving

Researchers are frequently faced with the analysis of microarray data of a relatively large number of genes using a small number of tissue samples. We examine the application of two statistical methods for clustering such microarray expression data: EMMIX-GENE and GeneClust. EMMIX-GENE is a mixture-model based clustering approach, designed primarily to cluster tissue samples on the basis of the genes. GeneClust is an implementation of the gene shaving methodology, motivated by research to identify distinct sets of genes for which variation in expression could be related to a biological property of the tissue samples. We illustrate the use of these two methods in the analysis of Affymetrix oligonucleotide arrays of well-known data sets from colon tissue samples with and without tumors, and of tumor tissue samples from patients with leukemia. Although the two approaches have been developed from different perspectives, the results demonstrate a clear correspondence between gene clusters produced by GeneClust and EMMIX-GENE for the colon tissue data. It is demonstrated, for the case of ribosomal proteins and smooth muscle genes in the colon data set, that both methods can classify genes into co-regulated families. It is further demonstrated that tissue types (tumor and normal) can be separated on the basis of subtle distributed patterns of genes. Application to the leukemia tissue data produces a division of tissues corresponding closely to the external classification, acute myeloid meukemia (AML) and acute lymphoblastic leukemia (ALL), for both methods. In addition, we also identify genes specific for the subgroup of ALL-Tcell samples. Overall, we find that the gene shaving method produces gene clusters at great speed; allows variable cluster sizes and can incorporate partial or full supervision; and finds clusters of genes in which the gene expression varies greatly over the tissue samples while maintaining a high level of coherence between the gene expression profiles. The intent of the EMMIX-GENE method is to cluster the tissue samples. It performs a filtering step that results in a subset of relevant genes, followed by gene clustering, and then tissue clustering, and is favorable in its accuracy of ranking the clusters produced.

scholarly journals The Role of OmpR in Bile Tolerance and Pathogenesis of Adherent-Invasive Escherichia coli

2021 ◽  
Vol 12 ◽  
Author(s):  
Valentina Lucchini ◽  
Adeline Sivignon ◽  
Michel Pieren ◽  
Marc Gitzinger ◽  
Sergio Lociuro ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Bile Salts ◽  
Membrane Integrity ◽  
Sodium Deoxycholate ◽  
Prototype Strain ◽  
Bile Tolerance ◽  
Gut Colonization ◽  
Main Component

Gut microbiota dysbiosis toward adherent-invasive Escherichia coli (AIEC) plays an important role in Crohn’s disease (CD). The OmpR transcriptional regulator is required for the AIEC LF82 prototype strain to adhere and invade intestinal epithelial cells. In this study, we explored the role of OmpR in AIEC pathogenesis using a panel of eight Escherichia coli strains isolated from CD patients and identified as AIEC. The deletion of ompR together with the implementation of two cell-based assays revealed that the role of OmpR in adhesion in vitro was not conserved in AIEC clinical strains. Nevertheless, we showed that OmpR was required for robust gut colonization of transgenic mice expressing human CEACAM receptors, suggesting that OmpR is involved in alternative virulence mechanisms in AIEC strains. We found that deletion of ompR compromised the ability of AIEC strains to cope with the stress induced by bile salts, which may be key for AIEC pathogenesis. More specifically, we demonstrated that OmpR was involved in a tolerance mechanism toward sodium deoxycholate (DOC), one of bile salts main component. We showed that the misregulation of OmpF or the loss of outer membrane integrity are not the drivers of OmpR-mediated DOC tolerance, suggesting that OmpR regulates a specific mechanism enhancing AIEC survival in the presence of DOC. In conclusion, the newly discovered role of OmpR in AIEC bile tolerance suggests that OmpR inhibition would interfere with different aspects of AIEC virulence arsenal and could be an alternative strategy for CD-treatment.

scholarly journals Associations between dietary patterns and gene expression pattern in peripheral blood mononuclear cells: a cross-sectional study

2020 ◽  
Author(s):  
Jacob J. Christensen ◽  
Stine M. Ulven ◽  
Magne Thoresen ◽  
Kenneth Westerman ◽  
Kirsten B. Holven ◽  
...  
Keyword(s):  
Gene Expression ◽  
Network Analysis ◽  
Peripheral Blood Mononuclear Cells ◽  
Dietary Patterns ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Expression Profiles ◽  
Gene Clusters ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells

AbstractBackgroundDiet may alter gene expression in immune cells involved in cardio-metabolic disease susceptibility. However, we still lack a robust understanding of the association between diet and immune cell-related gene expression in humans.ObjectiveOur objective was to examine the associations between dietary patterns (DPs) and gene expression profiles in peripheral blood mononuclear cells (PBMCs) in a population of healthy, Norwegian adults.MethodsWe used factor analysis to define a posteriori DPs from food frequency questionnaire-based dietary assessment data. In addition, we derived interpretable features from microarray-based gene expression data (13 967 transcripts) using two algorithms: CIBERSORT for estimation of cell subtype proportions, and weighted gene co-expression network analysis (WGCNA) for cluster discovery. Finally, we associated DPs with either CIBERSORT-predicted PBMC leukocyte distribution or WGCNA gene clusters using linear regression models. All analyses were gender-stratified (n = 130 women and 105 men).ResultsWe detected three DPs that broadly reflected Western, Vegetarian, and Low carbohydrate diets. CIBERSORT-predicted percentage of monocytes associated strongly and negatively with the Vegetarian DP in both women and men. For women, the Vegetarian DP associated most strongly with a large gene cluster consisting of 600 genes mainly involved in regulation of DNA transcription. For men, the Western DP inversely associated most strongly with a smaller cluster of 36 genes mainly involved in regulation of metabolic and inflammatory processes. In subsequent protein-protein interaction network analysis, the most important driver genes within these WGCNA gene clusters seemed to physically interact in biological networks.ConclusionsDPs may affect percentage monocytes and regulation of key biological processes within the PBMC pool. Although the present findings are exploratory, our analysis pipeline serves a useful framework for studying the association between diet and gene expression.

scholarly journals Expression Analysis of Cytokine and Chemokine Genes during the Natural Course of Murine Experimental Autoimmune Uveoretinitis

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Noriyasu Hashida ◽  
Nobuyuki Ohguro ◽  
Kohji Nishida
Keyword(s):  
Gene Expression ◽  
Cluster Analysis ◽  
Hierarchical Cluster Analysis ◽  
Expression Profiles ◽  
Hierarchical Cluster ◽  
Gene Clusters ◽  
Dynamic Changes ◽  
Taqman Gene Expression Assay ◽  
Experimental Autoimmune Uveoretinitis ◽  
Experimental Autoimmune

C57BL/6 mice were immunized with human interphotoreceptor retinoid-binding protein peptides to induce experimental autoimmune uveoretinitis (EAU). From the day of immunization to 30 days later, RNA was isolated daily from the mouse eyes. Dynamic changes in gene expression during the pathogenesis of EAU were analyzed by TaqMan gene expression assay that contained most chemokines/cytokines and their receptors, and signal transducer and activator of transcription (STAT) family genes, using beta-actin as the endogenous control. Gene clusters based on their expression profiles were analyzed to determine the candidate genes for the pathogenesis of inflammation. Hierarchical cluster analysis showed gene expression during EAU development in seven clustering patterns. Hierarchical cluster analysis also identified four distinct phases in daily expression: entrance, acceleration, deceleration, and remission. Gene expression changes in the EAU active phase showed synergetic upregulation of Th1-type genes (IFN-gamma and CXCL10/IP-10) with elevated Th2-type genes (CCL17/TARC and IL-5). Sequential expression changes of STAT1, STAT6, and STAT3 genes represented the dynamic changes of Th1, Th2, and Th17-type inflammatory genes, respectively. The expression pattern of STAT1 was representative of many gene movements. Our results suggested that coordinated action of Th1, Th2, and Th17 genes and STAT family genes are involved in EAU development and resolution.

Actions and interactions of progesterone and estrogen on transcriptome profiles of the bovine endometrium

2010 ◽  
Vol 42A (4) ◽  
pp. 290-300 ◽  
Author(s):  
Takashi Shimizu ◽  
Stefan Krebs ◽  
Stefan Bauersachs ◽  
Helmut Blum ◽  
Eckhard Wolf ◽  
...  
Keyword(s):  
Gene Expression ◽  
Steroid Hormones ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Gene Clusters ◽  
Catecholamine Metabolism ◽  
Response Patterns ◽  
Hormone Response ◽  
Promoter Regions ◽  
Estrogen Response

The aim of our study was to analyze endometrial gene expression profiles in ovariectomized cows treated with estradiol and/or progesterone by using microarray analysis. Clustering of differentially expressed genes allowed separation into distinct hormone response patterns. These patterns could be classified into independent and interdependent actions of the steroid hormones estrogen and progesterone. The use of ovariectomized cows and external administration of hormones identified a set of genes whose regulation depends on a progesterone priming effect. The progesterone-primed estrogen response comprises gene functions such as migration, cell differentiation, and cell adhesion and therefore may play a crucial role in tissue remodeling, as one of its key regulators in the endometrium, TGFB2, is among this group of progesterone-primed genes. Functional annotation analysis of the estrogen-responsive gene clusters shows a clear dominance of functions such as cell cycle, morphogenesis, and differentiation. The functional profile of the progesterone-responsive clusters is less clear but nevertheless shows some important fertility-related terms like luteinization, oocyte maturation, and catecholamine metabolism. We looked for putative regulators of the steroid hormone response in endometrium by searching for enriched transcription factor binding sites in the promoter regions of the genes with similar hormone response profile. This analysis identified transcription factors such as SP1, NFYA, FOXA2, IRF2, ESR1, and NOBOX as candidate regulators of gene expression in bovine endometrium treated with steroid hormones. Taken together, our data provide novel insights into the regulation of bovine endometrial physiology by steroid hormones.

scholarly journals Whole Transcriptome Analysis Identifies Distinct Gene Expression Profiles between SF3B1mut and SF3B1 wt Myelodysplastic Syndrome with Ring Sideroblasts

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3695-3695
Author(s):  
Gabriele Todisco ◽  
Maria Creignou ◽  
Elsa Bernard ◽  
Ann-Charlotte Björklund ◽  
Pedro Luis Moura ◽  
...  
Keyword(s):  
Gene Expression ◽  
Myelodysplastic Syndrome ◽  
Mononuclear Cells ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Gene Clusters ◽  
P Value ◽  
Specific Expression ◽  
Molecular Features ◽  
Ring Sideroblasts

Abstract Background and aims - The 2016 revised WHO classification incorporated somatic mutation in SF3B1 spliceosome gene within the diagnostic criteria of myelodysplastic syndrome (MDS) with ring sideroblasts (RS). However, SF3B1wt MDS-RS display significantly different clinical features and outcome from those of SF3B1mut MDS-RS. Recently, the recognition of SF3B1-mutant MDS as a distinct nosologic entity has been proposed to overcome this limitation. Methods - To evaluate the biological relevance of this proposal, we studied a consecutive cohort of 132 MDS with RS >5% using a pangenomic approach (targeted-DNA sequencing, genome-wide copy number variation analysis and bulk RNA-sequencing of CD34+ bone marrow mononuclear cells). 16 age-matched healthy individuals and 43 MDS-SLD/MLD negative for both splicing mutation and RS were included in this study as controls. Results - Unsupervised clustering analysis based on mutation profiles identified two major clusters predicted by SF3B1 mutation (87 MDS-RS-SF3B1mut and 45 MDS-RS-SF3B1wt). The most recurrently mutated genes in MDS-RS-SF3B1wt were TP53(40%), SRSF2(38%), TET2 (33%), ASXL1 (21%) and DNMT3A (12%). SRSF2 and TP53 mutations were found to be mutually exclusive with SF3B1 (p-value <0.05), whereas no difference was found in TET2, DNMT3A and ASXL1 frequencies between MDS-RS-SF3B1 mutand MDS-RS-SF3B1wt subgroups. TP53-mutated MDS-RS exhibited shorter overall survival (median 1.3 years, log-rank p-value<0.0001) compared to SF3B1mut (median 7.6 years), SRSF2mut (median 3.4 years) and MDS-RS without the abovementioned aberrations (median 4.4 years). Notably, allelic imbalances analysis of oncogenic variants identified a significant enrichment of TP53 biallelic inactivation in MDS-RS-SF3B1wt (64% vs 0, p<0.01). Differential gene expression analysis results were incorporated into a specific expression signature highly predictive of MDS-RS-SF3B1 mutand MDS-RS-SF3B1wt subgroups (Figure 1). The resulting gene clusters were classified in RS-specific genes (cluster 1 and 2) and SF3B1-specific genes (cluster 3 and 4). RS-specific genes comprising heme and hypoxia genes were enriched (Figure 2AB) and correlated with RS percentage (p<0.01). Pathway analysis revealed a specific downregulation of adhesion molecules and an upregulation of G-protein coupled receptor signaling molecules in MDS-RS-SF3B1mut. Among SF3B1-specific genes (Figure 2CD), we confirmed ABCB7 downregulation and identified new molecular targets that may concur to the pathophysiology of SF3B1-driven myeloid neoplasms. Conclusions - This study contributes to unveil molecular features of SF3B1-mutant MDS and provides further evidence to support recognition of somatic SF3B1 mutation as a disease-defining genetic lesion. Disclosures Papaemmanuil: Isabl Technologies: Divested equity in a private or publicly-traded company in the past 24 months; Kyowa Hakko Kirin Pharma: Consultancy.

1327: Gene Expression Profiles in Benign Prostatic Hyperplasia

2004 ◽  
Vol 171 (4S) ◽  
pp. 349-350
Author(s):  
Gaelle Fromont ◽  
Michel Vidaud ◽  
Alain Latil ◽  
Guy Vallancien ◽  
Pierre Validire ◽  
...  
Keyword(s):  
Gene Expression ◽  
Benign Prostatic Hyperplasia ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Prostatic Hyperplasia

The Oral Intake of Organic Germanium, Ge-132, Elevates α-Tocopherol Levels in the Plas-ma and Modulates Hepatic Gene Expression Profiles to Promote Immune Activation in Mice

2014 ◽  
Vol 84 (3-4) ◽  
pp. 0183-0195 ◽  
Author(s):  
Takashi Nakamura ◽  
Tomoya Takeda ◽  
Yoshihiko Tokuji
Keyword(s):  
Gene Expression ◽  
Immune Activation ◽  
Expression Profiles ◽  
Water Soluble ◽  
Alpha Tocopherol ◽  
Hepatic Gene Expression ◽  
Tocopherol Concentration ◽  
Altered Expression ◽  
Atp Production ◽  
Transfer Protein

The common water-soluble organic germanium compound poly-trans-[(2-carboxyethyl) germasesquioxane] (Ge-132) exhibits activities related to immune responses and antioxidant induction. In this study, we evaluated the antioxidative effect of dietary Ge-132 in the plasma of mice. Male ICR mice (seven mice per group) received an AIN-76 diet with 0.05 % Ge-132; three groups received the Ge-132-containing diet for 0, 1 or 4 days. The plasma alpha-tocopherol (α-tocopherol) concentration increased from 6.85 to 9.60 μg/ml after 4 days of Ge-132 intake (p < 0.05). We evaluated the changes in hepatic gene expression related to antioxidative activity as well as in the entire expression profile after one day of Ge-132 intake, using DNA microarray technology. We identified 1,220 genes with altered expression levels greater than 1.5-fold (increased or decreased) as a result of Ge-132 intake, and α-tocopherol transfer protein (Ttpa) gene expression was increased 1.62-fold. Immune activation was identified as the category with the most changes (containing 60 Gene Ontology (GO) term biological processes (BPs), 41 genes) via functional clustering analysis of altered gene expression. Ge-132 affected genes in clusters related to ATP production (22 GO term BPs, 21 genes), lipid metabolism (4 GO term BPs, 38 genes) and apoptosis (5 GO term BPs). Many GO term BPs containing these categories were significantly affected by the Ge-132 intake. Oral Ge-132 intake may therefore have increased plasma α-tocopherol levels by up-regulating α-tocopherol transfer protein (Ttpa) gene expression.

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