Global gene expression profile of INS1E cells, hIAPP-INS1E cells and rIAPP-INS1E cells.
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ABSTRACT:
ORGANISM(S): Rattus norvegicus
PROVIDER: GSE57573 | GEO | 2014/10/03
SECONDARY ACCESSION(S): PRJNA246721
REPOSITORIES: GEO
Similar Datasets
Project description:Islet amyloid polypeptide (IAPP) is the main component of amyloid deposits in type 2 diabetic patients. Cells overexpressing the human transcript of IAPP (hIAPP) present defects in insulin secretion. In this dataset, we include the expression data obtained from the rat pancreatic beta-cells INS1E stably transfected with human (hIAPP) or rat (rIAPP) IAPP, which lead to the overexpression of the different variants of IAPP protein. We also include INS1E cells with empty vector as control. 6 samples were analyzed from 3 INS1E clones stably transfected with different IAPP transcripts.
2014-10-03 | E-GEOD-57573 | biostudies-arrayexpress
Project description:Type 2 diabetes (T2D) is a common metabolic disease due to insufficient insulin secretion by pancreatic beta cells in the context of insulin resistance. Islet molecular pathology reveals a role for protein misfolding in beta cell dysfunction and loss with islet amyloid derived from islet amyloid polypeptide (IAPP), a protein co-expressed and co-secreted with insulin. The most toxic form of misfolded IAPP is intracellular membrane disruptive toxic oligomers present in beta cells in T2D and in beta cells of mice transgenic for human IAPP (hIAPP). Prior work revealed a high degree of overlap of transcriptional changes in islets from T2D and pre-diabetic 9-10-week-old mice transgenic for hIAPP with most changes being pro-survival adaptations and therefore of limited therapeutic guidance. Here we investigated islets from hIAPP transgenic mice at an earlier age (6 weeks) to screen for potential mediators of hIAPP toxicity that precede predominance of pro-survival signaling. We identified early suppression of cholesterol synthesis and trafficking along with aberrant intra-beta cell cholesterol and lipid deposits, and impaired cholesterol trafficking to cell membranes. These findings align with comparable lipid deposits present in beta cells in T2D and increased vulnerability to develop T2D in individuals taking medications that suppress cholesterol synthesis.
2024-07-03 | GSE256432 | GEO
Project description:The islet in type 2 diabetes (T2D) is characterized by amyloid deposits derived from islet amyloid polypeptide (IAPP), a protein co-expressed with insulin by β-cells. In common with amyloidogenic proteins implicated in neurodegeneration, human IAPP (hIAPP) forms membrane permeant toxic oligomers implicated in misfolded protein stress. Here, we establish that hIAPP misfolded protein stress activates HIF1α/PFKFB3 signaling, this increases glycolysis disengaged from oxidative phosphorylation with mitochondrial fragmentation and perinuclear clustering, considered a protective posture against increased cytosolic Ca2+ characteristic of toxic oligomer stress. In contrast to tissues with the capacity to regenerate, β-cells in adult humans are minimally replicative, and therefore fail to execute the second pro-regenerative phase of the HIF1α/PFKFB3 injury pathway. Instead, β-cells in T2D remain trapped in the pro-survival first phase of the HIF1α injury repair response with metabolism and the mitochondrial network adapted to slow the rate of cell attrition at the expense of β-cell function.
2020-04-17 | MTBLS951 | MetaboLights
Project description:Aggregation of islet amyloid polypeptide (IAPP) into islet amyloid results in β-cell toxicity in human type 2 diabetes. To determine the effect of islet amyloid formation on gene expression, we performed RNA-seq analysis using cultured islets from either wild-type mice (mIAPP), which are not amyloid prone, or mice that express human IAPP (hIAPP), which develop amyloid. Comparing mIAPP and hIAPP islets, 5025 genes were differentially regulated (2439 upregulated and 2586 downregulated). When considering gene sets (reactomes), 248 and 52 pathways were up- and downregulated, respectively. Of the top 100 genes upregulated under two conditions of amyloid formation, seven were common. Of these seven genes, only steroidogenic acute regulatory protein AQ2 (Star) demonstrated no effect of glucose per se to modify its expression. We confirmed this differential gene expression using quantitative reverse transcription polymerase chain reaction and also demonstrated the presence of StAR protein in islets containing amyloid. Furthermore, Star is a part of reactomes representing metabolism, metabolism of lipids, metabolism of steroid hormones, metabolism of steroids and pregnenolone biosynthesis. Thus, examining gene expression that is differentially regulated by islet amyloid has the ability to identify new molecules involved in islet physiology and pathology applicable to type 2 diabetes.
2019-08-29 | GSE135276 | GEO
Project description:The purpose of this experiment was to determine changes in gene expression by bone marrow-derived macrophages (BMDMs) treated with synthetic human vs. rodent islet amyloid polypeptide (IAPP). Synthetic human IAPP at 15 uM aggregates to form fibrils in vitro, whereas rodent IAPP is non-amyloidogenic. We hypothesized that interaction of macrophages with human IAPP aggregates can activate pro-inflammatory signalling pathways in macrophages, as described for other amyloidogenic peptides. This array includes eight samples from one experiment, with two groups of four replicates each. Each replicate represents BMDMs from one well of a 24-well plate. The control group was treated with 15 uM rat IAPP for 12 hours prior to total RNA extraction; the experimental group was treated with 15 uM human IAPP.
2010-08-11 | E-GEOD-23534 | biostudies-arrayexpress
Project description:The purpose of this experiment was to determine changes in gene expression by bone marrow-derived macrophages (BMDMs) treated with synthetic human vs. rodent islet amyloid polypeptide (IAPP). Synthetic human IAPP at 15 uM aggregates to form fibrils in vitro, whereas rodent IAPP is non-amyloidogenic. We hypothesized that interaction of macrophages with human IAPP aggregates can activate pro-inflammatory signalling pathways in macrophages, as described for other amyloidogenic peptides.
2010-08-11 | GSE23534 | GEO
Project description:Islet transplantation for treatment of diabetes is limited by availability of donor islets and requirements for immunosuppression. Stem cell-derived islets might circumvent these issues. SC-islets effectively control glucose metabolism post transplantation, but do not yet achieve full function in vitro with currently published differentiation protocols. We aimed to identify markers of mature subpopulations of SC-β cells by studying transcriptional changes associated with in vivo maturation of SC-β cells using RNA-seq and co-expression network analysis. The β cell-specific hormone islet amyloid polypeptide (IAPP) emerged as the top candidate to be such a marker. IAPP+ cells had more mature β cell gene expression and higher cellular insulin content than IAPP- cells in vitro. IAPP+ INS+ cells were more stable in long-term culture than IAPP- INS+ cells and retained insulin expression after transplantation into mice. Finally, we conducted a small molecule screen to identify compounds that enhance IAPP expression. Aconitine up-regulated IAPP and could help to optimize differentiation protocols.
2024-04-15 | GSE263366 | GEO
Project description:Complement inhibitor C4b-binding protein (C4BP) is synthesized in liver and pancreas and composed of 7 identical alpha chains and one unique beta chain. We showed previously that C4BP binds islet amyloid polypeptide (IAPP) and affects fibril formation in vitro. Now we found that polymeric C4BP inhibited lysis of human erythrocytes incubated with monomeric IAPP while no erythrocyte lysis was observed after incubation with preformed IAPP fibrils. In contrast, monomeric alpha chain of C4BP had significantly reduced activity. Further, addition of monomeric IAPP to a rat insulinoma cell line (INS-1) resulted in decreased cell viability, which was restored in the presence of physiological concentrations of C4BP. Accordingly, addition of C4BP rescued the ability of INS-1 cells and isolated rat islets to respond to glucose stimulation with insulin secretion, which was impaired in the presence of IAPP alone. C4BP was internalized together with IAPP into INS-1 cells and therefore we aimed to study its effect on gene expression. Pathway analyses of mRNA expression microarray data indicated that cells exposed to C4BP and IAPP in comparison to IAPP alone increased expression of genes involved in cholesterol synthesis. Depletion of cholesterol through methyl-β-cyclodextrin or cholesterol oxidase abolished the protective effect of C4BP on IAPP cytotoxicity of INS-1 cells. Also, inhibition of phosphoinositide 3-kinase but not NF-κB had a similar effect. Taken together, one of the mechanisms by which C4BP protects beta-cells from IAPP cytotoxicity is by enhancing cholesterol synthesis. The INS-1 cells were grown as 5 separate clones for 10 passages before plating in a 12-well plate (Nunc) at 100.000 cells per well and grown in complete RPMI 1640 medium to 70% confluency for approximately 48 h. The cells were then challenged by adding 77 μM monomeric IAPP alone or together with C4BP (0.6 μM). DMSO (1%) used as solvent for IAPP as well as C4BP (0.6 μM) alone were used as controls. RNA was extracted after 10h incubation and analysis carried out using Rat Gene 2.0 array chip (Affymetrix).
2016-08-25 | E-GEOD-79224 | biostudies-arrayexpress
Project description:The islet amyloid polypeptide (IAPP), a pancreas-produced peptide, has beneficial functions in its monomeric form. However, IAPP aggregates, related to type 2 diabetes mellitus (T2DM), are toxic not only for the pancreas, but also for the brain. In the latter, IAPP is often found in vessels, where it is highly toxic for pericytes, cells that have contractile properties and regulate capillary blood flow. The aim of this study is to assess whether IAPP oligomers alter the morphology and contractility of pericytes using an in vitro brain vasculature model and evaluate the association between IAPP and capillary contraction in human brain tissue.
2023-03-11 | PXD035048 | Pride
Project description:Complement inhibitor C4b-binding protein (C4BP) is synthesized in liver and pancreas and composed of 7 identical alpha chains and one unique beta chain. We showed previously that C4BP binds islet amyloid polypeptide (IAPP) and affects fibril formation in vitro. Now we found that polymeric C4BP inhibited lysis of human erythrocytes incubated with monomeric IAPP while no erythrocyte lysis was observed after incubation with preformed IAPP fibrils. In contrast, monomeric alpha chain of C4BP had significantly reduced activity. Further, addition of monomeric IAPP to a rat insulinoma cell line (INS-1) resulted in decreased cell viability, which was restored in the presence of physiological concentrations of C4BP. Accordingly, addition of C4BP rescued the ability of INS-1 cells and isolated rat islets to respond to glucose stimulation with insulin secretion, which was impaired in the presence of IAPP alone. C4BP was internalized together with IAPP into INS-1 cells and therefore we aimed to study its effect on gene expression. Pathway analyses of mRNA expression microarray data indicated that cells exposed to C4BP and IAPP in comparison to IAPP alone increased expression of genes involved in cholesterol synthesis. Depletion of cholesterol through methyl-β-cyclodextrin or cholesterol oxidase abolished the protective effect of C4BP on IAPP cytotoxicity of INS-1 cells. Also, inhibition of phosphoinositide 3-kinase but not NF-κB had a similar effect. Taken together, one of the mechanisms by which C4BP protects beta-cells from IAPP cytotoxicity is by enhancing cholesterol synthesis.
2016-08-25 | GSE79224 | GEO