The gastrointestinal (GI) tract can have significant impact on the regulation of the whole body metabolism and may contribute to the development of obesity and diabetes. To systemically elucidate the role of the GI tract in obesity, we performed a transcriptomic analyses in different parts of the GI tract of two obese mouse models: ob/ob and high-fat diet (HFD) fed mice. Compared to their lean controls, both obese mouse groups had significant amount of gene expression changes in the stomach (ob/ob: 959; HFD: 542), much more than the number of changes in the intestine. Despite the difference in genetic background, the two mouse models shared 296 similar gene expression changes in the stomach. Among those genes, some had known associations to obesity, diabetes and insulin resistance. In addition, the gene expression profile strongly suggested an increased gastric acid secretion in both obese mouse models, probably through an activation of the gastrin pathway. In conclusion, our data reveal a previously unknown dominant connection between the stomach and obesity.
Significant obesity-associated gene expression changes occur in the stomach but not intestines in obese mice.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Neuronopathic Gaucher disease: dysregulated mRNAs and miRNAs in brain pathogenesis and effects of pharmacologic chaperone treatment in a mouse model.
Specimen part
View SamplesColon gene expression in human IBD. The three major clinical subsets of Inflammatory Bowel Disease (IBD) include colon-only Crohn's Disease (CD), ileo-colonic CD, and Ulcerative Colitis (UC). These experiments tested differential colon gene expression in these three types of IBD, relative to healthy control samples, and the local degree of mucosal inflammation as measured by the CD Histological Index of Severity (CDHIS). Colon biopsy samples were obtained from IBD patients at diagnosis and during therapy, and healthy controls. The global pattern of gene expression was determined using GeneSpring software, with a focus upon candidate genes identified in a recent genome wide association study in pediatric onset IBD. Data suggested that two of these candidate genes are up regulated in pediatric IBD, partially influenced by local mucosal inflammation.
Loci on 20q13 and 21q22 are associated with pediatric-onset inflammatory bowel disease.
No sample metadata fields
View SamplesActivation of inflammatory pathways in human IBD
Activation of an IL-6:STAT3-dependent transcriptome in pediatric-onset inflammatory bowel disease.
No sample metadata fields
View SamplesFamilial hypertrophic cardiomyopathy (FHC) is a disease characterized by ventricular hypertrophy, fibrosis, and aberrant systolic and/or diastolic function. Our laboratories have previously developed 2 mouse models that affect cardiac performance. One transgenic mouse model encodes an FHC-associated mutation in -tropomyosin (Tm180) that displays severe cardiac hypertrophy with fibrosis and impaired physiological performance. The other model was a gene knockout of phospholamban (PLB), a regulator of calcium uptake in the sarcoplasmic reticulum of cardiomyocytes; the hearts of these mice exhibit hypercontractility with no pathological abnormalities. Previous work in our laboratories show that the hearts of mice that were genetically crossed between the Tm180 and PLB KO mice rescues the hypertrophic phenotype and improves their cardiac morphology and function.
Microarray analysis of active cardiac remodeling genes in a familial hypertrophic cardiomyopathy mouse model rescued by a phospholamban knockout.
Age, Specimen part
View SamplesActivation of inflammatory pathways in human IBD. Leukocyte recruitment pathways including those for eosiniphils are activated in the affected colon in IBD. However, the functional implications of this are not known. We hypothesized that pro-inflammatory eotaxin (CCL11) dependent networks would be up regulated in the colon of pediatric patients with Ulcerative Colitis (UC), and that these would regulate eosinophil recruitment to the gut. These experiments tested differential colon gene expression relative to these pathways in healthy and UC samples. Colon biopsy samples were obtained from UC patients at diagnosis, and healthy controls. The global pattern of gene expression was determined using GeneSpring software, and biological networks were identified using Ingenuity software. Data suggested that a leukocyte recruitment network which includeds CCL11 is up regulated in pediatric UC at diagnosis. The degree of up regulation of these genes compared to healthy controls was remarkably conserved within the UC patient group, suggesting common mechanisms of mucosal inflammation.
Intestinal macrophage/epithelial cell-derived CCL11/eotaxin-1 mediates eosinophil recruitment and function in pediatric ulcerative colitis.
No sample metadata fields
View SamplesCD38, a multi-functional membrane receptor and enzyme, consumes NAD+ to generate products such as cyclic-ADP-ribose. CD38 knockout mice show elevated tissue and blood NAD+ level. Chronic feeding of high-fat, high-sucrose diet to wild type mice leads to exercise intolerance and reduced metabolic flexibility. Loss of CD38 by genetic mutation protects mice from diet-induced metabolic deficit. These animal model results suggest that elevation of tissue NAD+ through genetic ablation of CD38 can profoundly alter energy homeostasis in animals that are maintained on a calorically-excessive Western diet.
Genetic Ablation of CD38 Protects against Western Diet-Induced Exercise Intolerance and Metabolic Inflexibility.
Specimen part
View SamplesThe Kruppel-like factor 5 (Klf5) regulates pluripotent stem cell self-renewal but its role in somatic stem cells is unknown. Klf5 deficient hematopoietic stem cells and progenitors (HSC/P) fail to engraft after transplantation. This HSC/P defect was associated with impaired bone marrow (BM) homing and lodging and decreased retention in BM. The Klf5/ HSC/P homing defect associated with decreased adhesion to fibronectin and expression of membrane-bound 1/2-integrins. In vivo inducible gain-of-function of Klf5 in HSC translated into increased HSC/P adhesion. The expression of Rab5 family members, mediators of 1/2-integrin recycling in the early endosome, was decreased in Klf5/ HSC/P. Klf5 binds directly to the promoter of Rab5a/b and overexpression of Rab5b rescued the expression of activated 1/2-integrins, adhesion and BM homing of Klf5/ HSC/P. Altogether, these data indicate that Klf5 is indispensable for adhesion, homing, lodging and retention of HSC/P in the BM through Rab5-dependent post-translational regulation of Beta1/Beta2 integrins.
Klf5 controls bone marrow homing of stem cells and progenitors through Rab5-mediated β1/β2-integrin trafficking.
Specimen part
View SamplesMyelodysplastic Syndromes (MDS) result from expansion of defective hematopoietic stem/progenitor clones. There is an urgent need to develop targeted therapies capable of eliminating the defective MDS clones. We identified that IRAK1, an immune modulating kinase, is overexpressed and hyperactivated in MDS. MDS-propagating clones treated with a small-molecule IRAK1 inhibitor (IRAK1/4-Inh) exhibited impaired expansion and increased apoptosis, which coincided with TRAF6/NF-B inhibition. Suppression of IRAK1, either by RNAi or with IRAK1/4-Inh, is selectively detrimental to MDS clones as normal CD34+ cells are preserved. Based on conclusions derived from an integrative gene expression analysis, we combined IRAK1 and BCL2 inhibitors and found that co-treatment collaboratively and selectively eliminated MDS clones. In summary, these findings implicate IRAK1 as a drugable target in MDS.
No associated publication
Treatment
View SamplesIn order to identify targets for HDAC4, NRVM were infected with adenoviral vectors encoding beta-Galactosidase or Flag- HDAC4, and incubated in serum free or 10% fetal calf serum containing growth medium for 48 hrs.
Modulation of chromatin position and gene expression by HDAC4 interaction with nucleoporins.
Specimen part
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