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<biogps><data><item key="owner">ArrayExpress Uploader</item><item key="pop_total">0</item><item key="species">mouse</item><item key="factors"><item><item key="GSM1067240"><item key="DRINKING WATER">distilled water for 21 days</item><item key="GENOTYPE">wild type</item></item></item><item><item key="GSM1067240"><item key="DRINKING WATER">distilled water for 21 days</item><item key="GENOTYPE">wild type</item></item></item><item><item key="GSM1067242"><item key="DRINKING WATER">distilled water containing 2mg/dl of sodium tungstate for 21 days</item><item key="GENOTYPE">wild type</item></item></item><item><item key="GSM1067242"><item key="DRINKING WATER">distilled water containing 2mg/dl of sodium tungstate for 21 days</item><item key="GENOTYPE">wild type</item></item></item><item><item key="GSM1067244"><item key="DRINKING WATER">distilled water for 21 days</item><item key="GENOTYPE">Irs2 knockout (Irs2 -/-)</item></item></item><item><item key="GSM1067244"><item key="DRINKING WATER">distilled water for 21 days</item><item key="GENOTYPE">Irs2 knockout (Irs2 -/-)</item></item></item><item><item key="GSM1067246"><item key="DRINKING WATER">distilled water containing 2mg/dl of sodium tungstate for 21 days</item><item key="GENOTYPE">Irs2 knockout (Irs2 -/-)</item></item></item><item><item key="GSM1067246"><item key="DRINKING WATER">distilled water containing 2mg/dl of sodium tungstate for 21 days</item><item key="GENOTYPE">Irs2 knockout (Irs2 -/-)</item></item></item></item><item key="id">7136</item><item key="ownerprofile_id">arrayexpress_sid</item><item key="platform">6</item><item key="summary_wrapped">Relative beta cell deficit and increased beta cell apoptosis are hallmarks of type 2 diabetes (T2D). The Insulin/Insulin Growth Factor...</item><item key="geo_gse_id">E-GEOD-43620</item><item key="owner_profile">/profile/8773/arrayexpressuploader</item><item key="factor_count">2</item><item key="sample_count">8</item><item key="tags"><item>basal</item><item>beta cell</item><item>body</item><item>cell</item><item>central</item><item>genome</item><item>glucose</item><item>insulin</item></item><item key="lastmodified">Dec.12, 2014</item><item key="is_default">False</item><item key="geo_gds_id"/><item key="slug">effects-of-sodium-tungstate-administration-in-irs2</item><item key="geo_id_plat">E-GEOD-43620_A-AFFY-45</item><item key="name">Effects of sodium tungstate administration in Irs2 -/- mice</item><item key="created">Nov.12, 2014</item><item key="summary">Relative beta cell deficit and increased beta cell apoptosis are hallmarks of type 2 diabetes (T2D). The Insulin/Insulin Growth Factor (Igf) signaling pathway is an established regulator of beta cell survival and is found downregulated in human T2D islets. The Insulin Receptor Substrate 2 (Irs2) plays a central role in the coordination of this pathway in beta cells. Thus, Irs2 knockout mice (Irs2 -/-) exhibit increased beta cell apoptosis that leads to a progressive decline of beta cell mass and hyperglycaemia. In this study, we sought to determine whether the anti-diabetic compound sodium tungstate could prevent the onset of diabetes in Irs2 -/- mice. Oral administration of tungstate resulted in an overall improvement in whole-body glucose tolerance in Irs2 -/- mice which correlated with increased beta cell mass. Enhanced beta cell mass was due to a dramatic reduction of beta cell apoptosis without changes in proliferation. Whole genome gene profiling analysis of islets isolated from treated Irs2 -/- mice confirmed a broad impact of tungstate on cell death pathways. Mechanistically, tungstate induced Erk1/2 phosphorylation in islets in vitro and, in agreement, treated Irs2 -/- islets exhibited increased basal Erk1/2 phosphorylation. Tungstate also downregulated expression of apoptosis-related genes in Irs2-/- islets in vitro, uncovering a direct effect of this compound in islets. All together, our data demonstrate that tungstate can restore beta cell mass and glucose homeostasis in a context of deficient Insulin/Igf signaling. This study underscores the importance of developing strategies specifically designed to arrest beta cell apoptosis as a means to prevent progressive beta cell failure in diabetes. 10-week old WT and Irs2 -/- mice were randomly divided into two treatment group, in a total of 4 experimental groups. For 21 days one group received distilled water as drinking water (untreated group) whilst the other received ad libitum a solution of 2mg/ml of sodium tungstate in distilled water (treated group). For each experimental group 2 independent samples were analysed, in a total of 8 samples.</item><item key="source">http://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-43620</item><item key="sample_source">http://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-43620/samples/</item></data></biogps>
