Analysis of gut microbiota by pyrosequencing of 16S rRNA gene in F344 rats
ABSTRACT: Chronic acid suppression by proton pump inhibitor (PPI) has been hypothesized to alter the gut microbiota via a change in intestinal pH. To evaluate the changes in gut microbiota composition by long-term PPI treatment. Twenty-four week old F344 rats were fed with (n = 5) or without (n = 6) lansoprazole (PPI) for 50 weeks. Then, profiles of luminal microbiota in the terminal ileum were analyzed. Pyrosequencing for 16S rRNA gene was performed by genome sequencer FLX (454 Life Sciences/Roche) and analyzed by metagenomic bioinformatics.
Project description:Sequencing of 16S ribosomal RNA (rRNA) gene, which has improved the characterization of microbial community, has made it possible to detect a low level Helicobacter pylori (HP) sequences even in HP-negative subjects which were determined by a combination of conventional methods. This study was conducted to obtain a cutoff value for HP colonization in gastric mucosa biopsies and gastric juices by the pyrosequencing method. Corresponding author: Department of Internal Medicine, Seoul National University Bundang Hospital, Seoungnam, Gyeonggi-do, Korea; Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea (Tel., +82-31-787-7008; e-mail, firstname.lastname@example.org). Microbial DNA from gastric mucosal samples [gastric antrum (n=63, mucosal biopsy), follow-up sample on gastric antrum (n=16, mucosal biopsy), and gastric body (n=18, mucosal biopsy)] and gastric juices (n=4, not mucosal biopsy) was amplified by nested PCR using universal bacterial primers, and the 16S rRNA genes were pyrosequenced.
Project description:Early life respiratory viral infections and atopic characteristics are significant risk factors for the development of childhood asthma. It is hypothesized that repeated respiratory viral infections might induce structural remodeling by interfering with the normal process of lung maturation; however, the specific molecular processes that mediate these developments are not understood. To define relevant molecular pathways, we used a well-established Sendai virus infection model in weanling rats to compare transcriptome signatures between a post-infection asthma prone susceptible strain (BN) and a post-infection asthma resistant strain (F344). Specific to this weanling model and not described in adult models, Sendai virus infection in the susceptible strain resulted in morphological abnormalities in distal airways that persist into adulthood, suggesting a disruption of normal lung growth. Gene expression data from infected and control lungs across five time points indicated that specific features of the immune response following viral infection were heightened and prolonged in lungs from BN compared with F344 rats. These features included an increase in macrophage cell number and related gene expression, which then transitioned to an increase in mast cell number and related gene expression. In contrast to the heightened immune response in infected BN lungs, infected F344 lungs displayed more efficient re-epithelialization. We conclude that the structural defects that developed and persisted in infected BN but not F344 lungs were preceded by a pronounced macrophage and mast cell response to viral infection acting in parallel with an inadequate re-epithelialization. For each of the five time points, one array was run for each of the four conditions (F344 control, BN control, F344 virus, BN virus) with 15 individual smaples pooled on each array.
Project description:Transcriptome from high throughput sequencing-by-synthesis is a good resource of molecular markers. In this study, we present utility of massively parallel sequencing by synthesis for profiling the transcriptome of red pepper (Capsicum annuum L. TF68) by 454 GS-FLX pyrosequencing. Through the generation of approximately 30.63 megabases (Mb) of Expressed Sequence Tags (ESTs) data with the average length of 375 base pairs (bp), 9,818 contigs and 23,712 singletons were obtained by assembly. Using BLAST alignment against NCBI non-redundant and a UniProt protein database, 30% of the tentative consensus sequences were assigned to specific function annotation, while 24% returned alignments of unknown function, leaving up to 46% with no alignment. Functional classification using FunCat revealed that sequences with putative known function were distributed cross 18 categories. Furthermore, over 200 high quality single nucleotide discrepancies were discovered using the Bukang cDNA collection as a reference database. Moreover, 758 simple sequence repeat (SSR) motif loci were mined from over 600 contigs, from which 572 primer sets were designed. The SSR motifs corresponded to di- and tri- nucleotide motifs (27.03 and 61.92%, respectively). These molecular markers may be of great value for application in linkage mapping and association mapping research. 1 sample TF68 accession examined
Project description:The goal of this study is to explore genes that are differentially expressed in E. coli C strains (wt and a butanol-tolerant mutant) after 1-butanol treatment. The butanol-tolerant mutant strain PKH5000 (denoted by 'E' for 'evolved') were derived from KCTC 2571 (wt) (denoted by 'A' for 'ancestral') by proton beam irradiation. 0 and 1 in sample title mean before and after butanol treatment, respectively. All microarray experiments were carried out in triplicate (rep1-3). Probes were spotted in duplicate on separate area of each microarray slide, which produces two GPR files (a and b suffixes).
Project description:Acute lung inflammation can alter the pulmonary function of susceptible individuals and exacerbate the pathogenesis of chronic inflammatory lung diseases including chronic obstructive pulmonary disease (COPD), cystic fibrosis and asthma. Exposure to lipopolysaccharide (LPS) or endotoxin, a constituent of outer cell membrane of gram negative bacteria, induces airway inflammation that is primarily characterized by increased polymorphonuclear neutrophils (PMNs) at early time points. Because LPS is present in variety of occupational and home environments and is an active constituent of cigarette smoke it is a risk factor for increasing prevalence and severity of non-occupational COPD, for adult onset of asthma and for wheezing in children. In airway epithelial cells, LPS stimulation increases mucin gene expression and mucous production. Hypersecretion of mucus overwhelms the ciliary clearance and obstructs airways, causing morbidity and mortality in chronic inflammatory respiratory lung diseases. In addition, acute bacterial infection contributes to the exacerbation of chronic airway diseases, specifically in advanced COPD and CF subjects, leading to increased healthcare burden and higher mortality. Bcl-2, a prosurvival protein that inhibits cell death plays a key role in normal cellular homeostasis and regulates the integrity of the mitochondrial and endoplasmic reticulum membranes. Gain- and loss-of-function studies showed that Bcl-2 expression sustains hyperplastic epithelial cells, and Bcl-2 expression is elevated in airway epithelial cells of subjects with cystic fibrosis and asthma. The present study investigated which inflammatory mediators induce mucous cell metaplasia and Bcl-2 expression following LPS exposure. Microarray analyses of mRNA from airway epithelial cells captured by laser microdissection from rat lungs snap-frozen at day 0 and 2 post LPS exposure were analyzed. Microarray analysis of mRNA from airway epithelial cells captured by laser microdissection from rat lungs snap-frozen at day 0 and day 2 post LPS exposure was performed to identify inflammatory mediators modulated by LPS exposure. Specific pathogen-free F344/NCrR male rats of 8–10 wk of age (from NCI, Frederick, MD) were exposed to LPS (1000 ug in 0.5 ML Saline) and rats were sacrificed on day 0 and day 2 of LPS exposure. Right lungs were snap-frozen in OCT and airway epithelial cells were captured by laser-dissection microsopy to extract RNA. Gene expression data from nonexposed rats (0d) was used a control.
Project description:The NIEHS data set (endpoint C) was provided by the National Institute of Environmental Health Sciences (NIEHS) of the National Institutes of Health (Research Triangle Park, NC, USA). The study objective was to use microarray gene expression data acquired from the liver of rats exposed to hepatotoxicants to build classifiers for prediction of liver necrosis. The gene expression compendium data set was collected from 418 rats exposed to one of eight compounds (1,2-dichlorobenzene, 1,4-dichlorobenzene, bromobenzene, monocrotaline, N-nitrosomorpholine, thioacetamide, galactosamine, and diquat dibromide). All eight compounds were studied using standardized procedures, i.e. a common array platform (Affymetrix Rat 230 2.0 microarray), experimental procedures and data retrieving and analysis processes. For each compound, four to six male, 12 week old F344 rats were exposed to a low dose, mid dose(s) and a high dose of the toxicant and sacrificed at 6, 24 and 48 hrs later. At necropsy, liver was harvested for RNA extraction, histopathology, and clinical chemistry assessments.
Project description:This study was designed to identify molecular changes induced by radiation in mouse lung. Mouse left lung was irradiated with a single dose of radiation. Total RNA from the irradiated lung tissue was subject to single channnel microarray.
Project description:Embryonic exposure to the endocrine disruptor vinclozolin during gonadal sex determination appears to promote an epigenetic reprogramming of the male germ line that is associated with transgenerational adult-onset disease states. Transgenerational effects on the embryonic day 16 (E16) testis demonstrated reproducible changes in the testis transcriptome for multiple generations (F1-F3). The expression of 196 genes was found to be influenced, with the majority of gene expression being decreased or silenced. Dramatic changes in the gene expression of methyltransferases during gonadal sex determination were observed in the F1 and F2 vinclozolin generation (E16) embryonic testis, but the majority returned to control-generation levels by the F3 generation. The most dramatic effects were on the germ-line-associated Dnmt3A and Dnmt3L isoforms. Observations demonstrate that an embryonic exposure to vinclozolin appears to promote an epigenetic reprogramming of the male germ line that correlates with transgenerational alterations in the testis transcriptome in subsequent generations. Experiment Overall Design: E16 Testis RNA samples from F1, F2, F3 generation control groups are compared to F1, F2, F3 generation vinclozolin treated groups
Project description:Like humans, the NOD mouse and other diabetes susceptible rat strains, T1D in BB rats is dependent on the major histocompatibility complex (MHC, insulin dependent diabetes mellitus locus 1, Iddm1) located on chromosome 20. In rats this is the HLA-DQB1 homologue RT1-B, specifically the RT1u haplotype. Our studies employ congenic derivatives of the BB rat, the DRlyp/lyp and DR+/+ strains, which differ only by the 2 Mb lyp (lymphopenia, Iddm2) region on chromosome 4. TID in the lymphopenic DRlyp/lyp rat is spontaneous and onset occurs in 100% of animals during adolescence (65.3+/-6.3 days) due to a recessive mutation within GIMAP5 (GTPase, IMAP family member 5). Gimap5 is a mitochondrial GTP-binding protein necessary for post-thymic T cell survival. The spontaneously diabetic phenotype observed in DRlyp/lyp rats is thought to be elicited through deficiency in CD4+CD25+ TREG cells as T1D in lymphopenic BB rats can be rescued through adoptive transfer of this population. Genetic variation in GIMAP5 has been associated with the development of protein-tyrosine phosphatase-2 (IA-2) autoantibodies in human T1D  and is significantly associated with systemic lupus erythematosus (SLE). The non-lymphopenic DR+/+ strain possesses wild-type GIMAP5 alleles and does not develop spontaneous T1D, however, T1D is inducible through administration of lymphotoxic anti-RT6 monoclonal antibody and immune activating polyinosinic polycytidylic acid (poly I:C; a ligand of toll-like receptor 3), or through viral depletion of CD4+CD25+ regulatory T (TREG) cells. Such treatments do not induce T1D in the related Wistar-Furth (WF) rats and suggest the presence of an underlying diabetic predisposition in BB rats that is phenotypically manifested upon loss of immune regulation. DRlyp/lyp and DR+/+ rats possess characteristics that make them ideal for the identification of pathways relevant to the development of T1D since they possess absolute or conditional susceptibility to T1D. The Gimap-/- Iddm2 locus conveys upon DRlyp/lyp rats a deficiency in immune regulatory capacity and the spontaneous T1D phenotype. Consistent with the concept that autoimmunity involves both a lack of self-tolerance as well as target organ-specific factors, we have discovered that DRlyp/lyp and DR+/+ (BB) rats share an islet specific stress. This is reflected by the expression of immune mediators, including the chemokine eotaxin that recruits eosinophils, certain T cell subsets, dendritic cells, and mast cells, by islet β cells early in life, before infiltration of immune cells into the islet (insulitis). While BB and WF rats share Iddm1 (RT1u/u MHC), islet eotaxin expression in not observed in WF islets and thus is associated with the T1D susceptibility of BB rats. Further supporting the hypothesis that additional genetic factors, perhaps those working at the level of the pancreatic β cell, are necessary for the development of T1D are the observations that 1) The generation Fischer 344 (F344) rats either homozygous for Gimap5-/- or homozygous for both RT1u/u and Gimap5-/- fail to develop T1D; and 2) genetic crosses between BB rats and non diabetic strains have identified numerous Iddm loci independent of Iddm1 and Iddm2. In this study, using islet gene expression profiling, direct serum-level measurement, quantitative real-time PCR and targeted histological follow-up, we investigate pancreatic islet gene expression in BB rat at 5 weeks (+/-5 days) which is prior to insulitis in DRlyp/lyp rats. We compare DR+/+, JB++, JBlyp/lyp and DRlyp/lyp islet activity to that of WF and F344 rats to investigate any potential for reduction in capability to deal with oxidative stress in BB rats compared to non-BB and whether any differences in that capability map to known Iddm regions.
Project description:Whole tissues corresponding to the ileum, colon and rectum were dissected from adult mice and used for RNA preparation. The aim of experiment was to study the impact of gut microbiota on gene expression in different gut regions. Experiment Overall Design: Three biological replicates were used for each condition. Each RNA preparation was independently hybridized to one chip.