Transcriptomic analyses of human islets
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE324084 | GEO | 2026/03/22
REPOSITORIES: GEO
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| Other | ||||
| GSE324084_Gene_counts_samples.txt.gz | Txt | |||
| GSE324084_RNAseqsamples_Figures_Group.xlsx | Xlsx |
Items per page: 5 1 - 3 of 3 |
Similar Datasets
Project description:insulin treatment protects islets from the initial rapid loss that is usually observed after transplantation and positively affects the outcome of islet transplantation in Akita mice. To study the molecular mechanism underlying the improved islet survival, expression profile analyses was performed to analyze the differences between the grafts transplanted into hyperglycemic and normoglycemic mice at 6 hours post-transplantation Cells were harvested at grafts for RNA extraction and hybridization on Affymetrix microarrays. We performed gene expression profiles of the transplanted mouse islets into hyperglycemic and normoglycemic mice at 6 hours post-transplantation
2014-04-18 | E-GEOD-55764 | biostudies-arrayexpress
Project description:insulin treatment protects islets from the initial rapid loss that is usually observed after transplantation and positively affects the outcome of islet transplantation in Akita mice. To study the molecular mechanism underlying the improved islet survival, expression profile analyses was performed to analyze the differences between the grafts transplanted into hyperglycemic and normoglycemic mice at 6 hours post-transplantation
2014-04-18 | GSE55764 | GEO
Project description:Recent advances in the understanding of the genetics of type 2 diabetes (T2D) susceptibility have focused attention on the regulation of transcriptional activity within the pancreatic beta-cell. MicroRNAs (miRNAs) represent an important component of regulatory control, and have proven roles in the development of human disease and control of glucose homeostasis. We set out to establish the miRNA profile of human pancreatic islets and of enriched beta-cell populations, and to explore their potential involvement in T2D susceptibility. We used Illumina small RNA sequencing to profile the miRNA fraction in three preparations each of primary human islets and of enriched beta-cells generated by fluorescence-activated cell sorting. In total, 366 miRNAs were found to be expressed (i.e. >100 cumulative reads) in islets and 346 in beta-cells; of the total of 384 unique miRNAs, 328 were shared. A comparison of the islet-cell miRNA profile with those of 15 other human tissues identified 40 miRNAs predominantly expressed (i.e. >50% of all reads seen across the tissues) in islets. Several highly-expressed islet miRNAs, such as miR-375, have established roles in the regulation of islet function, but others (e.g. miR-27b-3p, miR-192-5p) have not previously been described in the context of islet biology. As a first step towards exploring the role of islet-expressed miRNAs and their predicted mRNA targets in T2D pathogenesis, we looked at published T2D association signals across these sites. We found evidence that predicted mRNA targets of islet-expressed miRNAs were globally enriched for signals of T2D association (p-values <0.01, q-values <0.1). At six loci with genome-wide evidence for T2D association (AP3S2, KCNK16, NOTCH2, SCL30A8, VPS26A, and WFS1) predicted mRNA target sites for islet-expressed miRNAs overlapped potentially causal variants. In conclusion, we have described the miRNA profile of human islets and beta-cells and provide evidence linking islet miRNAs to T2D pathogenesis. Examination of the miRNA profiles in 3 preparations of isolated pancreatic islets and 3 preparations of FACS-enriched pancreatic beta-cells
2013-06-07 | E-GEOD-47720 | biostudies-arrayexpress
Project description:The homeodomain transcription factor Nkx6.1 plays an important role in pancreatic islet β-cell development, but its effects on adult β-cell function, survival, and proliferation are not well understood. In the present study, we demonstrated that treatment of primary rat pancreatic islets with a cytomegalovirus promoter-driven recombinant adenovirus containing the Nkx6.1 cDNA (AdCMV-Nkx6.1) causes dramatic increases in [methyl-3H] thymidine and 5-bromo-2'-deoxyuridine (BrdU) incorporation and in the number of cells per islet relative to islets treated with a control adenovirus (AdCMV-βGAL), whereas suppression of Nkx6.1 expression reduces thymidine incorporation. Immunocytochemical studies reveal that >80% of BrdU-positive cells in AdCMV-Nkx6.1-treated islets are β cells. Microarray, real-time PCR, and immunoblot analyses reveal that overexpression of Nkx6.1 in rat islets causes concerted upregulation of a cadre of cell cycle control genes, including those encoding cyclins A, B, and E, and several regulatory kinases. Cyclin E is upregulated earlier than the other cyclins, and adenovirus-mediated overexpression of cyclin E is shown to be sufficient to activate islet cell proliferation. Moreover, chromatin immunoprecipitation assays demonstrate direct interaction of Nkx6.1 with the cyclin A2 and B1 genes. Overexpression of Nkx6.1 in rat islets caused a clear enhancement of glucose-stimulated insulin secretion (GSIS), whereas overexpression of Nkx6.1 in human islets caused an increase in the level of [3H]thymidine incorporation that was twice the control level, along with complete retention of GSIS. We conclude that Nkx6.1 is among the very rare factors capable of stimulating β-cell replication with retention or enhancement of function, properties that may be exploitable for expansion of β-cell mass in treatment of both major forms of diabetes. Keywords: Insulin secretion, islet biology, transcription factor, cell cycle regulation, diabetes We utilized a âsample x referenceâ experimental design strategy in which RNA extracted from rat pancreatic islets was hybridized to the microarray slide in the presence of labeled rat reference RNA (RRR, Stratagene, LaJolla, CA). Cultures were treated with adenoviruses expressing either the hamster form of Nkx6.1 or the beta-galactosidase enzyme. 5 biological replicates each representing independent islet isolations were used for microarray analysis. Briefly, five hundred nanograms of total RNA were used for gene expression profiling following reverse transcription and T-7 polymerase-mediated amplification/labeling with Cyanine-5. Labeled subject cRNA was co-hybridized to Operon rat 27K oligonucleotide arrays with equimolar amounts of Cyanine-3 labeled RRR. Slides were hybridized, washed, and scanned on a Gene Pix 5000 microarray scanner.
2010-05-18 | E-GEOD-13153 | biostudies-arrayexpress
Project description:The homeodomain transcription factor Nkx6.1 plays an important role in pancreatic islet β-cell development, but its effects on adult β-cell function, survival, and proliferation are not well understood. In the present study, we demonstrated that treatment of primary rat pancreatic islets with a cytomegalovirus promoter-driven recombinant adenovirus containing the Nkx6.1 cDNA (AdCMV-Nkx6.1) causes dramatic increases in [methyl-3H] thymidine and 5-bromo-2'-deoxyuridine (BrdU) incorporation and in the number of cells per islet relative to islets treated with a control adenovirus (AdCMV-βGAL), whereas suppression of Nkx6.1 expression reduces thymidine incorporation. Immunocytochemical studies reveal that >80% of BrdU-positive cells in AdCMV-Nkx6.1-treated islets are β cells. Microarray, real-time PCR, and immunoblot analyses reveal that overexpression of Nkx6.1 in rat islets causes concerted upregulation of a cadre of cell cycle control genes, including those encoding cyclins A, B, and E, and several regulatory kinases. Cyclin E is upregulated earlier than the other cyclins, and adenovirus-mediated overexpression of cyclin E is shown to be sufficient to activate islet cell proliferation. Moreover, chromatin immunoprecipitation assays demonstrate direct interaction of Nkx6.1 with the cyclin A2 and B1 genes. Overexpression of Nkx6.1 in rat islets caused a clear enhancement of glucose-stimulated insulin secretion (GSIS), whereas overexpression of Nkx6.1 in human islets caused an increase in the level of [3H]thymidine incorporation that was twice the control level, along with complete retention of GSIS. We conclude that Nkx6.1 is among the very rare factors capable of stimulating β-cell replication with retention or enhancement of function, properties that may be exploitable for expansion of β-cell mass in treatment of both major forms of diabetes. Keywords: Insulin secretion, islet biology, transcription factor, cell cycle regulation, diabetes
2008-10-11 | GSE13153 | GEO
Project description:An increasing demand for cell-based diabetes therapy could be met through xenotransplantation of adult porcine islets. Use of islet xenotranplantation on a large scale would require rigorous safety and quality control measures to maximize transplant success. Development of molecular tools to monitor porcine islet cellular responses to ischemic, osmotic, mechanical and oxidative stresses during islet cell processing and post-isolation culturing would aid the rational design of cytoprotective strategies aimed at improving transplant outcomes. In addition, gene expression signatures informative for islet quality could serve as an adjunct to physiological testing to establish the suitability of islet products for transplantation. Nine adult Landrace sows (2-3.5 y old, 249±27 kg) were sacrificed, the pancreases were dissected, and islet cells isolated as previously described [8]. Islet preparation purity was assessed by light microscopy after staining with diphenylthiocarbazone and ranged between 90-95% for the preparations used. Islet yield, based on islet equivalents (IEQ, number of islets standardized to 150 µm diameter), was estimated at 1930±520 per gram of pancreas tissue.Profiles of islet cells cultured under standard conditions were compared to islet cells cultured under stress conditions with elevated glucose (16.7 mM) or addition of inflammatory cytokines (IL-1ï¢, TNF-ï¡, and IFN-ï§), or both, for 48 hours.
2010-07-01 | E-GEOD-4744 | biostudies-arrayexpress
Project description:Nkx6.1 target genes were identified in mature pancreatic islets by comparing gene expression in conditional Nkx6.1-ablated islets versus control islets using microarray analysis.
2013-09-12 | GSE40470 | GEO
Project description:Nkx6.1 target genes were identified in mature pancreatic islets by comparing gene expression in conditional Nkx6.1-ablated islets versus control islets using microarray analysis. Nkx6.1 was conditionally ablated in mature pancreatic islets by recombination of a Nkx6.1-flox allele using the tamoxifen-inducible Pdx1-CreERTM allele (Gu et al 2002). Mice were injected with 2 mg/25 g tamoxifen in corn oil four times between 4 and 6 weeks of age. Islets were isolated after the final tamoxifen injection. Total RNA was isolated and pooled from pancreata of 6 week old Nkx6.1fl/-;Pdx1-CreERTM (mutant) versus Nkx6.1fl/+;Pdx1-CreERTM (control) littermates for 3 biological replicates.
2013-09-12 | E-GEOD-40470 | biostudies-arrayexpress
Project description:The homeodomain transcription factor, Pdx-1, has important roles in pancreatic development and M-NM-2-cell function and survival. In the present study, we demonstrate that adenovirus-mediated overexpression of Pdx-1 in rat or human islets also stimulates cell replication. Moreover, co-overexpression of Pdx-1 with another homeodomain transcription factor, Nkx6.1, has an additive effect on proliferation compared to either factor alone, implying discrete activating mechanisms. Consistent with this, Nkx6.1 stimulates mainly M-NM-2-cell proliferation, whereas Pdx-1 stimulates both M-NM-1- and M-NM-2-cell proliferation. Furthermore, cyclins D1/D2 are upregulated by Pdx-1 but not by Nkx6.1, and inhibition of cdk4 blocks Pdx-1- but not Nkx6.1-stimulated islet cell proliferation. Genes regulated by Pdx-1 and not Nkx6.1 were identified by microarray analysis. Two members of the transient receptor potential cation (TRPC) channel family, TRPC3 and TRPC6, are upregulated by Pdx-1 overexpression, and siRNA-mediated knockdown of TRPC3/6 or TRPC6 alone inhibits Pdx-1-induced but not Nkx6.1-induced islet cell proliferation. Pdx-1 also stimulates ERK1/2 phosphorylation, an effect partially blocked by knockdown of TRPC3/6, and blockade of ERK1/2 activation with a MEK1/2 inhibitor partially impairs Pdx-1-stimulated proliferation. These studies define a pathway by which overexpression of Pdx-1 activates islet cell proliferation that is distinct from and additive to a pathway activated by Nkx6.1. We identified genes that were upregulated or downregulated at 48 h with Pdx-1 overexpression as compared to untreated and M-NM-2gal controls. We set up a microarray using primary rat islets that were left untreated or transduced with adenoviruses overexpressing M-NM-2gal or Pdx-1 for 48 h.
2013-09-01 | E-GEOD-49786 | biostudies-arrayexpress
Project description:Deterioration of functional islet β-cell mass is the final step in progression to Type 2 diabetes. We previously reported that overexpression of Nkx6.1 in rat islets has the dual effects of enhancing glucose-stimulated insulin secretion (GSIS) and increasing β-cell replication. Here we show that Nkx6.1 strongly upregulates the prohormone VGF in rat islets and that VGF is both necessary and sufficient for Nkx6.1-mediated enhancement of GSIS. Moreover, the VGF-derived peptide TLQP-21 potentiates GSIS in rat and human islets and improves glucose tolerance in vivo. Chronic injection of TLQP-21 in pre-diabetic ZDF rats preserves islet mass and slows diabetes onset. TLQP-21 prevents islet cell apoptosis by a pathway similar to that used by GLP-1, but independent of the GLP-1, GIP, or VIP receptors. Unlike GLP-1, TLQP-21 does not inhibit gastric emptying or increase heart rate. We conclude that a TLQP-21 is a novel agent for enhancing islet β-cell survival and function.
2012-05-10 | GSE37852 | GEO