Project description:In this study, 7530 newborn pancreatic β-cells were analyzed by single-cell sequencing. Cell Ranger was used to compare the original sequencing data, count the genome, filter background cells and cell transcript UMI, and use cell barcode to generate gene-barcode matrix. Then the samples were grouped, gene expression analysis, etc., and the statistical results of each sample sequencing data were output
Project description:We measured changes in the human islet proteome following 72-hr exposure to 3 mM R-beta-hydroxybutyrate. Islets from 12 metabolically healthy human islet donors were obtained from the Alberta Diabetes Institute Islet Core
Project description:We found that in rodents, postnatal beta-cell maturation is associated with changes in the expression of several islet microRNAs and discovered that these modifications are driven by changes in the nutrient supply. Mimicking the microRNA changes observed during β-cell maturation in newborn rat islet cells was sufficient to promote glucose-induced insulin release and to achieve a mature β-cell secretory phenotype. Moreover, the modifications in the level of some of these microRNAs reduced the proliferation of newborn β-cells, suggesting that they contribute to the limited proliferative capacity of adult β-cells. These findings demonstrated that miRNAs contribute to postnatal beta-cell maturation and development. Their role is likely to promote beta-cell adaptation to fule supply and to maintain glucose homeostasis by regulating insulin release and proliferation. Islets from 10-day-old rats (P10) (n=3) or 3-month-old male rat (n=3) were taken. Total RNA was extracted and mRNA profiling via Illumina single-end sequencing of mRNA-seq libraries was performed.
Project description:Islet β cells suffer from de- and trans-differentiation after injury. We used single cell RNA sequencing (scRNA-seq) to analyze the diversity of β cells in from STZ-induced diabetes.
Project description:We found that in rodents, postnatal beta-cell maturation is associated with changes in the expression of several islet microRNAs and discovered that these modifications are driven by changes in the nutrient supply. Mimicking the microRNA changes observed during ?-cell maturation in newborn rat islet cells was sufficient to promote glucose-induced insulin release and to achieve a mature ?-cell secretory phenotype. Moreover, the modifications in the level of some of these microRNAs reduced the proliferation of newborn ?-cells, suggesting that they contribute to the limited proliferative capacity of adult ?-cells. These findings demonstrated that miRNAs contribute to postnatal beta-cell maturation and development. Their role is likely to promote beta-cell adaptation to fule supply and to maintain glucose homeostasis by regulating insulin release and proliferation. Islets from 10-day-old rats (P10) (n=5) or 3-month-old male rat (n=6) were taken. Total RNA was extracted and microRNA profiling was performed using the Illumina TruSeq small RNA kit and single-end sequencing.
Project description:Fresh frozen sections of islets obtained by surgery were laser capture microdissected using autofluorescence to guide selection of beta cell areas of the islet. RNA was extracted and amplified with 2 rounds of T7 linear amplification. Two technical replicates were hybridized to Affymetrix U95Av2 arrays.
Project description:We found that in rodents, postnatal beta-cell maturation is associated with changes in the expression of several islet microRNAs and discovered that these modifications are driven by changes in the nutrient supply. Mimicking the microRNA changes observed during β-cell maturation in newborn rat islet cells was sufficient to promote glucose-induced insulin release and to achieve a mature β-cell secretory phenotype. Moreover, the modifications in the level of some of these microRNAs reduced the proliferation of newborn β-cells, suggesting that they contribute to the limited proliferative capacity of adult β-cells. These findings demonstrated that miRNAs contribute to postnatal beta-cell maturation and development. Their role is likely to promote beta-cell adaptation to fule supply and to maintain glucose homeostasis by regulating insulin release and proliferation. Islets from 10-day-old rats (P10) were taken, dispersed and transfected with control miRNA mimic or miR-17-5p. Total RNA was extracted and mRNA profiling via Illumina single-end sequencing of mRNA-seq libraries was performed. In parallel, Ago2 immunoprecipitation with RNA recovery and mRNA-seq was performed (RISC-seq).
Project description:Neonatal beta cells are considered developmentally immature and hence less glucose-responsive. To study the acquisition of mature glucose-responsiveness, we compared glucose-regulated redox state, insulin synthesis and secretion of beta cells purified from neonatal or 10-weeks old rats to their transcriptomes and proteomes measured by oligonucleotide and LC-MS/MS profiling. Lower glucose-responsiveness of neonatal beta cells was explained by two distinct properties: higher activity at low glucose and lower activity at high glucose. Basal hyperactivity was associated with higher NAD(P)H, a higher fraction of neonatal beta cells actively incorporating 3H-Tyrosine, and persistently increased insulin secretion below 5 mM glucose. Neonatal beta cells lacked the steep glucose-responsive NAD(P)H rise between 5-10 mM glucose characteristic for adult beta cells, and accumulated less NAD(P)H at high glucose. They had 2-fold lower expression of malate/aspartate-NADH shuttle and most glycolytic enzymes. Genome-wide profiling situated neonatal beta cells at a developmental crossroad: they showed advanced endocrine differentiation when specifically analyzed for their mRNA/protein level of classical neuroendocrine markers. On the other hand, discrete neonatal beta cell subpopulations still expressed mRNAs/proteins typical for developing/proliferating tissues. One example, Delta-like 1 homolog (DLK1) was used to investigate if neonatal beta cells with basal hyperactivity corresponded to a more immature subset with high DLK1, but no association was found. In conclusion, the current study supports the importance of glycolytic NADH-shuttling in stimulus-function coupling, presents basal hyperactivity as novel property of neonatal beta cells, and provides potential markers to recognize intercellular developmental differences in the endocrine pancreas.
Project description:Islet-1+ Cardiac Stem Cells (CSCs) derived from neonatal cardiac tissue are promising candidates for cardiac repair due to their ability to differentiate into all cells of the cardiovascular lineage and the innate ability of the neonatal heart to regenerate after injury. In this study we analyzed the transcriptome and differentiation capability of Islet-1+ cardiac progenitor cell clones isolated from neonatal human patient-derived tissue and demonstrated that matched ovine CSCs restore function when administered for cell-based repair in an allogeneic ovine model of myocardial infarction.