Project description:Genes involved in distinct diabetes types suggest shared disease mechanisms. We show that rare ONECUT1 coding variants cause monogenic recessive diabetes (neonatal or very early-onset, syndromic) in two unrelated patients, and monogenic dominant diabetes (early adult-onset) in heterozygous relatives of these and 13 additional unrelated cases. Patients heterozygous for rare ONECUT1 coding variants define a subgroup of T2D with early-onset diabetes and other features. In addition, common regulatory ONECUT1 variants are associated with multifactorial T2D. Directed differentiation of human pluripotent stem cells to the pancreatic lineage revealed that loss of ONECUT1 impairs pancreatic progenitor formation and a subsequent endocrine program. We uncovered that ONECUT1 activates the pro-endocrine genes NKX6.1 and NKX2.2 through binding to their cis-regulatory elements. Globally, ONECUT1-directed gene transcription occurs in association with major islet transcription factors, at clusters of pancreas- and endocrine-specific enhancers within open chromatin. ONECUT1 regulates a transcriptional and epigenetic machinery critical for proper endocrine pancreatic development, involved in a spectrum of diabetes, monogenic recessive and dominant, and multifactorial.
Project description:Custom array designed to tile Linkage Disequilibrium Blocks of T2D GWAS SNPs, monogenic candidates for T2D and Obesity, and all plausible imprinted loci from human and mouse data. Case Control comparison of MeDIP for Type 2 Diabetes. MeDIP versus Input fraction.
Project description:Context: Context: Gestational diabetes (GDM) has profound effects on the intrauterine metabolic milieu and is linked to obesity and diabetes in offspring, but the mechanisms driving these effects remain largely unknown. Alterations gene expression in amniocytes exposed to GDM in utero may identify potential mechanisms leading to metabolic dysfunction later in life. Objective: Objective: To profile changes in the transcriptome in human amniocytes exposed to GDM Methods: A nested case-control study was performed in second trimeseter amniocytes matched for offspring sex, maternal race/ethnicity, maternal age, gestational age at amniocentesis, gestational age at birth and gestational diabetes status. Sex-specific RNA-sequencing was completed and gene expression changes were identified. Results: Expression of interferon-stimulated genes was increased in GDM amniocytes accounting for 6 of the top 10 altered genes (q<0.05). Enriched biological pathways in GDM anmiocytes included pathways involving inflammation, the interferon response, fatty liver disease, monogenic diabetes and atherosclerosis. Conclusion: In a unique repository of human amniocytes exposed to GDM in utero, trancriptome analysis identified enrichment of inflammation and interferon-related pathways.
2020-05-15 | GSE150621 | GEO
Project description:whole exon sequencing for monogenic diabetes
Project description:The goals and objectives: To study Type 2 diabetes progression and the development of insulin resistance in two animal models with and without a high fat diet superimposed on these models. Background: Diabetes is a systemic metabolic imbalance involving multiple tissues/organs, and an early hallmark feature of this disease state is insulin resistance. Multifactorial interactions of genetics, prenatal environmental factors (fetal programming) and postnatal environmental factors (nutrition and activity) likely contribute to the diabetic phenotype.Animal models can serve as a valuable tool for studying diabetes disease progression and for identifying useful biomarkers of type 2 diabetes. Several inbred rodent models are available for diabetes related studies. The GK rat is an obvious choice among available inbred models as the genetic basis for this inheritable form of diabetes is polygenic (5), unlike most other inbred rodent models that exhibit single gene defects. Many of the characteristics of the GK rat mirror human diabetes (hyperglycemia, glucose intolerance, insulin resistance), although hyperlipidemia does not appear to be prominent in the GK rat. Due to its polygenic mode of inheritance and 100% penetrance, the GK rat may be a useful model for human diabetes. Induced animal models can also be useful in diabetes studies. One such model is metabolic syndrome resulting from experimentally induced fetal programming (produced by maternal malnutrition or by exposure to corticosteroids in the third trimester). Both in humans and animals, accumulating evidence suggests that alterations in the human fetal environment can result in permanent physiologic changes that manifest as increased incidence of adult onset pathology. Numerous epidemiological studies have forged a strong link between low birth weight and the development of metabolic syndrome in adulthood. From such observations has arisen the concept of “fetal programming” whereby exposure to some factor(s) during crucial stages in development can permanently alter or “reset” physiologic/metabolic functions. In the rat, exposure to corticosteroids during a “window” in third trimester gestation (CS programming) results in fetal growth retardation and insulin resistance in adult offspring. Genetic factors play a primarily role in the etiology of diabetes in the GK rat, whereas fetal environmental factors are causative in CS programming. (It should be noted that although altered fetal environmental effects, most likely stemming from maternal hyperglycemia, have been implicated to play some role in the decreased pancreatic B cell mass in GK rats, these effects occur earlier in gestation and therefore differ from programming by CS in late gestation.) A comparison of the development of insulin resistance in the GK rat with development in the CS programmed rat will provide insight into genetic and fetal environmental factors in disease development. Superimposing dietary alterations (i.e., high fat feeding) (11) on both animal models may aid in the dissection of multiple interacting factors (genetic, fetal environmental factors, postnatal environmental factors) on the development and progression of insulin resistance and type 2 diabetes. Such studies may also aid in the identification of useful biomarkers for insulin resistance and type 2 diabetes in humans. Proposed research: Experiments are designed to study disease progression and the development of insulin resistance in two animal models: the GK rat and the CS programmed rat, with and without a high fat diet superimposed on these models. Animals will be maintained in our facility from weaning (GK rats) or birth (CS programmed - WKY), and body weights taken weekly. Appropriate diets (normal or high fat) will be introduced at weaning. Groups of animals (N=6) will be sacrificed at 5 different ages: 4, 8, 12, 16, and 20 weeks. Plasma samples will be analyzed for markers of hyperglycemia, hyperinsulinemia, dyslipidimia, and for selected other hormonal factors which may contribute to disease etiology (adiponectin, leptin, corticosterone). At sacrifice, muscle is harvested, flash-frozen in liquid nitrogen, and warehoused in our tissue collection maintained at - 80 degrees C for this and possible future work. Study will initially focus on examination of selected molecular markers of insulin resistance at the mRNA level in rat liver (PEPCK, PDK4). Keywords: Type 2 diabetes, biomarker, rat, liver, time series
Project description:Type I diabetes (T1D) impairs bone accrual in patients, but the mechanism is unclear. Here in a murine monogenic model for T1D, we demonstrate that diabetes suppresses bone formation resulting in a rapid loss of both cortical and trabecular bone. Single-cell RNA sequencing uncovers metabolic dysregulation in bone marrow osteogenic cells of the diabetic mice. In vivo stable isotope tracing reveals impaired glycolysis in diabetic bone that is highly responsive to insulin stimulation. Remarkably, deletion of the insulin receptor reduces cortical but not trabecular bone. Increasing glucose uptake by overexpressing Glut1 in osteoblasts exacerbates bone defects in T1D mice. Conversely, activation of glycolysis by Pfkfb3 overexpression preserves both trabecular and cortical bone mass in the face of diabetes. The study identifies defective glucose metabolism in osteoblasts as a pathogenic mechanism for osteopenia in T1D, and furthermore implicates boosting osteoblast glycolysis as a potential anabolic therapy.
Project description:Type I diabetes (T1D) impairs bone accrual in patients, but the mechanism is unclear. Here in a murine monogenic model for T1D, we demonstrate that diabetes suppresses bone formation resulting in a rapid loss of both cortical and trabecular bone. Single-cell RNA sequencing uncovers metabolic dysregulation in bone marrow osteogenic cells of the diabetic mice. In vivo stable isotope tracing reveals impaired glycolysis in diabetic bone that is highly responsive to insulin stimulation. Remarkably, deletion of the insulin receptor reduces cortical but not trabecular bone. Increasing glucose uptake by overexpressing Glut1 in osteoblasts exacerbates bone defects in T1D mice. Conversely, activation of glycolysis by Pfkfb3 overexpression preserves both trabecular and cortical bone mass in the face of diabetes. The study identifies defective glucose metabolism in osteoblasts as a pathogenic mechanism for osteopenia in T1D, and furthermore implicates boosting osteoblast glycolysis as a potential anabolic therapy.
Project description:The goals and objectives: To study Type 2 diabetes progression and the development of insulin resistance in two animal models with and without a high fat diet superimposed on these models. Background: Diabetes is a systemic metabolic imbalance involving multiple tissues/organs, and an early hallmark feature of this disease state is insulin resistance. Multifactorial interactions of genetics, prenatal environmental factors (fetal programming) and postnatal environmental factors (nutrition and activity) likely contribute to the diabetic phenotype.Animal models can serve as a valuable tool for studying diabetes disease progression and for identifying useful biomarkers of type 2 diabetes. Several inbred rodent models are available for diabetes related studies. The GK rat is an obvious choice among available inbred models as the genetic basis for this inheritable form of diabetes is polygenic (5), unlike most other inbred rodent models that exhibit single gene defects. Many of the characteristics of the GK rat mirror human diabetes (hyperglycemia, glucose intolerance, insulin resistance), although hyperlipidemia does not appear to be prominent in the GK rat. Due to its polygenic mode of inheritance and 100% penetrance, the GK rat may be a useful model for human diabetes. Induced animal models can also be useful in diabetes studies. One such model is metabolic syndrome resulting from experimentally induced fetal programming (produced by maternal malnutrition or by exposure to corticosteroids in the third trimester). Both in humans and animals, accumulating evidence suggests that alterations in the human fetal environment can result in permanent physiologic changes that manifest as increased incidence of adult onset pathology. Numerous epidemiological studies have forged a strong link between low birth weight and the development of metabolic syndrome in adulthood. From such observations has arisen the concept of “fetal programming” whereby exposure to some factor(s) during crucial stages in development can permanently alter or “reset” physiologic/metabolic functions. In the rat, exposure to corticosteroids during a “window” in third trimester gestation (CS programming) results in fetal growth retardation and insulin resistance in adult offspring. Genetic factors play a primarily role in the etiology of diabetes in the GK rat, whereas fetal environmental factors are causative in CS programming. (It should be noted that although altered fetal environmental effects, most likely stemming from maternal hyperglycemia, have been implicated to play some role in the decreased pancreatic B cell mass in GK rats, these effects occur earlier in gestation and therefore differ from programming by CS in late gestation.) A comparison of the development of insulin resistance in the GK rat with development in the CS programmed rat will provide insight into genetic and fetal environmental factors in disease development. Superimposing dietary alterations (i.e., high fat feeding) (11) on both animal models may aid in the dissection of multiple interacting factors (genetic, fetal environmental factors, postnatal environmental factors) on the development and progression of insulin resistance and type 2 diabetes. Such studies may also aid in the identification of useful biomarkers for insulin resistance and type 2 diabetes in humans. Proposed research: Experiments are designed to study disease progression and the development of insulin resistance in two animal models: the GK rat and the CS programmed rat, with and without a high fat diet superimposed on these models. Animals will be maintained in our facility from weaning (GK rats) or birth (CS programmed - WKY), and body weights taken weekly. Appropriate diets (normal or high fat) will be introduced at weaning. Groups of animals (N=6) will be sacrificed at 5 different ages: 4, 8, 12, 16, and 20 weeks. Plasma samples will be analyzed for markers of hyperglycemia, hyperinsulinemia, dyslipidimia, and for selected other hormonal factors which may contribute to disease etiology (adiponectin, leptin, corticosterone). At sacrifice, muscle is harvested, flash-frozen in liquid nitrogen, and warehoused in our tissue collection maintained at - 80 degrees C for this and possible future work. Study will initially focus on examination of selected molecular markers of insulin resistance at the mRNA level in rat gastrocnemius muscles (IRS-1, PDK4). Keywords: Type 2 diabetes, biomarker, rat, muscle, time series
Project description:The goals and objectives: To study Type 2 diabetes progression and the development of insulin resistance in two animal models with and without a high fat diet superimposed on these models. Background: Diabetes is a systemic metabolic imbalance involving multiple tissues/organs, and an early hallmark feature of this disease state is insulin resistance. Multifactorial interactions of genetics, prenatal environmental factors (fetal programming) and postnatal environmental factors (nutrition and activity) likely contribute to the diabetic phenotype.Animal models can serve as a valuable tool for studying diabetes disease progression and for identifying useful biomarkers of type 2 diabetes. Several inbred rodent models are available for diabetes related studies. The GK rat is an obvious choice among available inbred models as the genetic basis for this inheritable form of diabetes is polygenic (5), unlike most other inbred rodent models that exhibit single gene defects. Many of the characteristics of the GK rat mirror human diabetes (hyperglycemia, glucose intolerance, insulin resistance), although hyperlipidemia does not appear to be prominent in the GK rat. Due to its polygenic mode of inheritance and 100% penetrance, the GK rat may be a useful model for human diabetes. Induced animal models can also be useful in diabetes studies. One such model is metabolic syndrome resulting from experimentally induced fetal programming (produced by maternal malnutrition or by exposure to corticosteroids in the third trimester). Both in humans and animals, accumulating evidence suggests that alterations in the human fetal environment can result in permanent physiologic changes that manifest as increased incidence of adult onset pathology. Numerous epidemiological studies have forged a strong link between low birth weight and the development of metabolic syndrome in adulthood. From such observations has arisen the concept of “fetal programming” whereby exposure to some factor(s) during crucial stages in development can permanently alter or “reset” physiologic/metabolic functions. In the rat, exposure to corticosteroids during a “window” in third trimester gestation (CS programming) results in fetal growth retardation and insulin resistance in adult offspring. Genetic factors play a primarily role in the etiology of diabetes in the GK rat, whereas fetal environmental factors are causative in CS programming. (It should be noted that although altered fetal environmental effects, most likely stemming from maternal hyperglycemia, have been implicated to play some role in the decreased pancreatic B cell mass in GK rats, these effects occur earlier in gestation and therefore differ from programming by CS in late gestation.) A comparison of the development of insulin resistance in the GK rat with development in the CS programmed rat will provide insight into genetic and fetal environmental factors in disease development. Superimposing dietary alterations (i.e., high fat feeding) (11) on both animal models may aid in the dissection of multiple interacting factors (genetic, fetal environmental factors, postnatal environmental factors) on the development and progression of insulin resistance and type 2 diabetes. Such studies may also aid in the identification of useful biomarkers for insulin resistance and type 2 diabetes in humans. Proposed research: Experiments are designed to study disease progression and the development of insulin resistance in two animal models: the GK rat and the CS programmed rat, with and without a high fat diet superimposed on these models. Animals will be maintained in our facility from weaning (GK rats) or birth (CS programmed - WKY), and body weights taken weekly. Appropriate diets (normal or high fat) will be introduced at weaning. Groups of animals (N=6) will be sacrificed at 5 different ages: 4, 8, 12, 16, and 20 weeks. Plasma samples will be analyzed for markers of hyperglycemia, hyperinsulinemia, dyslipidimia, and for selected other hormonal factors which may contribute to disease etiology (adiponectin, leptin, corticosterone). At sacrifice, muscle is harvested, flash-frozen in liquid nitrogen, and warehoused in our tissue collection maintained at - 80 degrees C for this and possible future work. Study will initially focus on examination of selected molecular markers of insulin resistance at the mRNA level in rat abdominal fat (PEPCK, IRS-1). Keywords: Type 2 diabetes, biomarker, adipose tissue, rat, time series