bluuebunny/crossref_metadata_2025 huggingface dataset:
1819-P: Growth Hormone Receptor (GHR) in AgRP Neurons Modulates Energy Balance and Metabolic Adaptation to Fasting via Sirtuin 1 (SIRT1)
Authors: DEBARBA LUCAS K. , AYYAR IVEN T. , KOCH MADELYNN C. , CADY GILLIAN , SADAGURSKI MARIANNA
Published: June 2019

We are facing a worldwide public health emergency due to the increasing epidemic of diabetes. In the central nervous system, the hypothalamus is the primary site of integration of the neuroendocrine and autonomic responses which maintain glucose and energy homeostasis. Main physiological effects of growth hormone (GH) in adult brain - is the inhibition of its own secretion, especially critical under fasting states. While the importance of hypothalamic GH receptor (GHR) in GH feedback inhibition is well established, the direct involvement of neuronal GHR signals in the regulation of whole-body homeostasis has not been studied. Previously, we have identified a unique population of hypothalamic leptin receptor (LepRb)-GHR expressing neurons that regulate hepatic glucose production, suggesting a crucial role for these neurons in GHR-neurocircuitry. To characterize hypothalamic GHR-expressing neurons, we have developed GHRcre mice using CRISPR/Cas9 technology. Approximately 60% of GHR+ neurons in the arcuate nucleus (ARC) co-localize with AgRP-expressing neurons and about 25% with GHRH neurons, basically representing most of ARCGHR neurons. By manipulating neuronal activity of neurochemically-defined GHR neurons, we demonstrate that ARCGHR neurons represent distinct neuronal population in glycemic control. Despite similarity in responses in both sexes, only female mice selectively lacking GHR in AgRP neurons showed impaired energy homeostasis and heat production, accompanied by alterations in metabolic adaptation to fasting. Fasting increased the abundance of sirtuin 1 (SIRT1) within ARCGHR+ neurons, while this pattern was diminished in the fasted AgRPEYFP∆GHR female mice. Our data suggests a role of SIRT1 within somatotropic signaling in the AgRPGHR+ neurons in response to alterations in nutritional status and demonstrates the role of AgRP-GHR neurons in assisting the organism in recruiting its resources for survival purposes.

Disclosure

L.K. Debarba: None. I.T. Ayyar: None. M.C. Koch: None. G. Cady: None. M. Sadagurski: None.

Funding

American Diabetes Association (1-18-JDF-063 to M.S.)
1821-P: A Possible Mechanism: Genistein Improves Metabolism and Induces White Fat Browning through Modulating Hypothalamic Expression of Ucn3, Depp, and Stc1
Authors: ZHOU LIYUAN , XIAO XINHUA , DENG MINGQUN , LIU JIEYING , YU MIAO
Published: June 2019

Bioactive food components have gained growing attention in recent years. Multitude of studies have demonstrated that genistein, as a soy-derived phytoestrogen, has beneficial effects on metabolism. However, the exact mechanism by which genistein improving metabolic disorders remains unclear, especially the central regulation. This study was designed to evaluate whether addition of genistein to the high-fat diet could counter the metabolic disorders and whether these alterations were associated with the gene expression in hypothalamus. C57BL/6 mice were fed either a high-fat diet (HF), high-fat diet with genistein (0.25g/kg diet) (HFG) or a normal control diet (CON) for eight weeks. Body weight were assessed during the study. After eight-week intervention, content of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and brown adipose tissue (BAT) were weighed. Glucose tolerance test, the serum levels of insulin and lipid were assessed. The mRNA of browning marker was detected in the WAT. The hypothalamus was collected for whole transcriptome sequencing and reverse transcription quantitative PCR (RT-qPCR) validation. The results demonstrated that mice fed the HFG diet had lower body weight (p<0.05) and SAT mass (p<0.01), decrease levels of low-density lipoprotein cholesterol (LDL-C) (p<0.01) and free fatty acids (FFA) (p<0.05), higher browning marker of Ucp1 (p<0.01) and Cidea (p<0.05) in WAT and an improvement in glucose tolerance and insulin sensitivity compared with those in the HF group. Transcriptome sequencing showed that there were three differentially expressed genes in hypothalamus among the three groups, including Ucn3 (p<0.05), Depp (p<0.01) and Stc1 (p<0.01). Thus, regulating gene expressions in hypothalamus is a potential mechanism for genistien improving metabolism and inducing WAT browning, which may provide a novel target for the precaution and treatment of T2DM.

Disclosure

L. Zhou: None. X. Xiao: None. M. Deng: None. J. Liu: None. M. Yu: None.

Funding

National Natural Science Foundation of China
1823-P: Evidence that Arcuate Nucleus Neurocircuit Remodeling Ameliorates Hyperglycemia in Type 2 Diabetes
Authors: MIRZADEH ZAMAN , CABRALES ELAINE , SCHWARTZ MICHAEL W.
Published: June 2019

Abnormal development of neurocircuits in the hypothalamic arcuate nucleus (ARC) is a common feature of genetic and acquired (e.g., postnatal overnutrition) models of obesity and type 2 diabetes (T2D). In leptin-deficient ob/ob mice, developmental defects occur both in efferent projections from the ARC to downstream circuits and in afferent GABAergic input onto ARC neurons. A developmental critical period (CP) has been proposed based on the temporally-restricted requirement for leptin, during the first month of life, to enable normal projections of ARC Agrp neurons in ob/ob mice. We recently described the formation of perineuronal nets (PNNs) around ARC Agrp neurons during the latter half of this CP, shortly following the peak of the postnatal leptin surge. PNNs, which are extracellular matrix specializations that restrict CP plasticity in neurons they enmesh, were overabundant in the ARC of adult ob/ob mice, suggesting that ARC neurocircuit dysfunction contributes to their metabolic phenotype. To remodel ARC neurocircuits containing PNN-enmeshed cells, we engrafted a special population of GABAergic inhibitory interneurons derived from the embryonic brain medial ganglionic eminence (MGE). Here we show that MGE interneurons derived from E13.5 GAD67-GFP embyros and transplanted bilaterally into the ob/ob ARC survive, integrate into local circuits, and form GABAergic synapses. Preliminary metabolic phenotyping shows that compared to vehicle injection, transplanted MGE cells (∼5000 MGE cells/ARC) induce a sustained reduction of hyperglycemia lasting for at least one month (1-month average BG: veh 301±12 vs. MGE 189±12 mg/dl, n=4/group, p=0.022) without significant effects on food intake or body weight. These findings suggest that sustained diabetes remission can be achieved by remodeling ARC neurocircuits through MGE cell transplantation.

Disclosure

Z. Mirzadeh: Consultant; Self; Novo Nordisk A/S. E. Cabrales: None. M.W. Schwartz: Consultant; Self; Novo Nordisk A/S. Research Support; Self; Novo Nordisk A/S.

Funding

National Institute of Neurological Disorders and Stroke
1827-P: Higher Glucagon-Like Peptide-1 Response and Lower Beta-Cell Glucose Sensitivity Are Associated with Increased Glycemic Variability among Individuals with Prediabetes
Authors: CHOW ELAINE , LUK ANDREA , LING JAMES , KONG ALICE P. , MA RONALD C. , FERRANNINI ELE , CHAN JULIANA C.
Published: June 2019

Background: Increased glycemic variability (GV) is thought to represent abnormalities of glucose homeostasis in the progression from prediabetes to diabetes. We evaluated the association between GV, beta-cell function and glucagon-like peptide 1 (GLP-1) response among individuals with prediabetes.

Methods: 61 individuals with prediabetes (age Mean±SD 56±9 years, 31 male) each wore a blinded continuous glucose monitor (Medtronic iPro2) for 72 hours. Standard deviation (SD) and coefficient of variation (CV) were calculated from CGM glucose. Participants underwent a 2-hour mixed-meal tolerance test with measurement of insulin, C-peptide, GLP-1 for modelling of beta-cell function.

Results: Early and late GLP-1/glucose ratio were positively correlated with CGM sensor glucose SD (r = 0.29, p=0.02 and r= 0.28 p = 0.048 respectively). Beta-cell glucose sensitivity (βCGS) was negatively correlated with SD (r = -0.28, p = 0.03). In multivariate analyses, only βCGS and GLP-1 response were significant predictors of SD, while early phase insulin and insulin secretion rate predicted average sensor glucose but not indices of GV.

Conclusions: Higher GLP-1 response and reduced βCGS are associated with greater glucose fluctuations in the prediabetic range.

Disclosure

E. Chow: Research Support; Self; Powder Pharmaceuticals Inc., Sanofi-Aventis. A. Luk: None. J. Ling: None. A.P. Kong: Advisory Panel; Self; Lilly Diabetes. Research Support; Self; AstraZeneca, Lilly Diabetes. Speaker's Bureau; Self; Abbott. Other Relationship; Self; AstraZeneca, Novartis Pharmaceuticals Corporation, Sanofi. R.C. Ma: Advisory Panel; Self; Boehringer Ingelheim International GmbH. Research Support; Self; AstraZeneca, Bayer AG, Pfizer Inc. Stock/Shareholder; Self; GemVCare. Other Relationship; Self; AstraZeneca. E. Ferrannini: None. J.C. Chan: Board Member; Self; Asia Diabetes Foundation. Consultant; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Lilly Diabetes, Medtronic, Merck Sharp & Dohme Corp., Sanofi-Aventis. Research Support; Self; Amgen Inc., AstraZeneca, Lee Powder, Lilly Diabetes, Pfizer Inc., Sanofi-Aventis. Speaker's Bureau; Self; Ascensia Diabetes Care. Stock/Shareholder; Self; GemVCare.
183-LB: The Gut Microbiome and Puberty in Girls at Risk for Type 2 Diabetes (T2D)
Authors: JOBIRA BEZA , FRANK DANIEL N. , PYLE LAURA , GROSS SUSAN , IR DIANA , PENDLETON WESLEY , ROBERTSON CHARLES E. , NADEAU KRISTEN J. , KELSEY MEGAN M.
Published: June 2019

Objectives: Pediatric-onset T2D is twice as common in girls vs. boys and is tightly linked with puberty and obesity. Alterations in gut microbiota, specifically the Firmicutes:Bacteroidetes ratio (F:B), may be associated with insulin sensitivity (Si) and may play a role in the pathophysiology of T2D. We aimed to evaluate associations between gut microbiome composition and Si and insulin secretion in obese prepubertal (PP) vs. late-pubertal (LP) girls.

Methods: Obese PP (N=9, age 8.5 ±0.8 year, BMIz 2.0±0.5) and LP (Tanner 4-5, N=9, age 13.0±2.0 year, BMIz 2.0±0.5) obese girls underwent stool collection and intravenous glucose tolerance testing after an overnight fast. High-throughput sequencing of the bacterial 16S rRNA gene V3-V4 region was used to profile fecal bacterial communities. Bergman's minimal model was used to estimate Si and insulin secretion (acute insulin response to glucose, AIRg) and disposition index (DI). T-tests assessed group differences in Si, AIRg and DI. Spearman’s correlation examined relationships between microbiota relative abundance (%RA) and Si, AIRg and DI.

Results: PP vs. LP girls had significantly higher Si (8.0±1.0 vs. 2.0±0.5 x10-4/min-1/μIU/ml, p<0.001) and DI (3,525 ± 636 vs. 1,687 ± 385 x10-4/min-1, p=0.03). AIRg was not different between PP and LP girls (568 ± 132 vs. 840 ± 174 μIU/ml, p=0.23). F:B ratio related to insulin secretion and DI, (r=-0.32, p=0.20; r=-0.39, p=0.11) but not Si. At the genus level, Si was correlated to Ruminococus and Lachnospira %RA (r=0.53, p=0.02; r=0.50, p=0.036). AIRg was correlated to Peptostreptococcaceae %RA (r=-0.48, p=0.045). DI was correlated with Prevotella and Bifidobacterium %RA (r=0.57, p=0.01; R=- 0.54, p=0.02).

Conclusion: These pilot study results suggest possible relationships among the gut microbiome, glucose metabolism, and puberty in girls at risk for T2D that merit further exploration.

Disclosure

B. Jobira: None. D.N. Frank: None. L. Pyle: None. S. Gross: None. D. Ir: None. W. Pendleton: None. C.E. Robertson: None. K.J. Nadeau: None. M.M. Kelsey: None.

Funding

University of Colorado Center for Women’s Health; National Institutes of Health/Colorado Clinical Translational Science Award (UL1TR002535)
1834-P: Pancreatic Fat Associates with Impaired Insulin Secretion in Genetically Predisposed Individuals
Authors: JAGHUTRIZ BENJAMIN , HENI MARTIN , MACHANN JÜRGEN , SCHICK FRITZ , ULLRICH SUSANNE , HAERING HANS-ULRICH , FRITSCHE ANDREAS , WAGNER ROBERT
Published: June 2019

Background: Pancreatic fat (PF) related beta-cell failure might play a role in the pathophysiology of type 2 diabetes (T2D). We hypothesized that the effect of PF on beta-cell function can be modeled as a gene x environment interaction. To this end, we investigated the association of PF with insulin secretion in subjects with different genetic predisposition for T2D.

Methods: A genome-wide polygenic risk score (gwPRS) was computed combining summary statistics from a genome-wide association study with ∼900.000 participants and 480.000 genetic variants in our cohort. The interaction of MRI-measured PF with gwPRS was investigated in 376 nondiabetic participants.

Results: PF interacted with gwPRS on insulin secretion after adjustment for confounders (p=0.001). In participants with low gwPRS, PF associated positively with insulin secretion. In participants with high gwPRS, there was a negative association with insulin secretion.

Discussion: PF is a pathophysiologic factor potentially contributing to both primary insulin hypersecretion and impairment of insulin secretion, dependent on genetic predisposition.

Disclosure

B. Jaghutriz: None. M. Heni: Research Support; Self; Boehringer Ingelheim International GmbH, Sanofi. Speaker's Bureau; Self; Lilly Diabetes, Merck Sharp & Dohme Corp., Sanofi. J. Machann: None. F. Schick: None. S. Ullrich: Advisory Panel; Spouse/Partner; AstraZeneca, Boehringer Ingelheim International GmbH, Lilly Diabetes, Merck Sharp & Dohme Corp., Mylan, Novo Nordisk A/S. Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc. H. Haering: None. A. Fritsche: None. R. Wagner: Other Relationship; Self; Lilly Diabetes, Novo Nordisk A/S.

Funding

German Federal Ministry of Education and Research
1837-P: Central IL-6 Receptor Deficiency Impairs Pancreatic Insulin Secretion
Authors: MCNEILLY ALISON D. , GALLAGHER JENNIFER , MCCRIMMON RORY J.
Published: June 2019

Inflammation has become a major mechanism linking obesity to type 2 diabetes (T2D). The pleiotropic cytokine, Interleukin 6 (IL-6) is pro-inflammatory and widely thought to negatively impact on obesity-induced insulin resistance. However, recent evidence challenges this concept. IL-6-deficient (IL-6−/−) mice develop mature onset obesity, glucose intolerance, insulin resistance, and increased liver inflammation in response to a high-fat diet. Here we investigate the CNS role of IL-6 in the manifestation of T2D using a neuronal-specific IL-6 receptor null mouse model.

IL-6Ra-/- mice were generated by crossing IL-6RaFlx/flx with Nestin-Cre+/-animals. Male IL-6Ra-/- and Cre+/- animals (18 weeks, n=12/group) were fed standard laboratory chow for 20 weeks. Body composition and energy homeostasis were assessed using EchoMRI and CLAMS systems. Insulin secretion by glucose-stimulated insulin secretion (GSIS) was measured both in vivo and ex-vivo in isolated β-cell preparations. Circulating insulin was measured by ELISA. Data are expressed as mean±SEM.

Body weight was comparable between IL-6Ra-/- and Cre+/- animals. Fat mass however was significantly reduced (20% reduction; p<0.05) despite animals being hyperphagic (28% increase; p<0.01). Energy expenditure was reduced (12% reduction) and the respiratory exchange ratio were significantly increased (18% increase) in IL-6Ra-/- animals (p<0.01 for both). Glucose and insulin tolerance were comparable. In vivo insulin secretion was markedly diminished in IL-6Ra-/- animals (GSIS AUC; 2.5±0.6 vs. 17.1±5.1, p<0.01). Histological analysis and stimulation of isolated pancreatic islets ex vivo however, showed similar islet morphology and GSIS or glucagon secretion (p=ns for all). Administration of hexamethonium, an Ach receptor blocker to IL-6Ra-/- animals restored GSIS in vivo (p=ns).

These finding suggest that classical IL-6 signaling within the CNS plays an important role in regulating insulin secretion via direct effect on β-cell function in vivo.

Disclosure

A.D. McNeilly: None. J. Gallagher: None. R.J. McCrimmon: Advisory Panel; Self; Eli Lilly and Company, Novo Nordisk A/S, Sanofi-Aventis. Research Support; Self; The Leona M. and Harry B. Helmsley Charitable Trust.

Funding

Diabetes UK
1839-P: GLP-1 Receptor Antagonism Using Exendin-9,39 in the Fasting State Modulates a-Cell Function in Humans with Type 2 Diabetes
Authors: HURTADO MARIA D. , EGAN AOIFE M. , LAURENTI MARCELLO C. , ADAMS J.D. , RIZZA ROBERT A. , COBELLI CLAUDIO , MATVEYENKO ALEKSEY , MAN CHIARA DALLA , VELLA ADRIAN
Published: June 2019

Glucagon-Like Peptide-1 (GLP-1) potentiates insulin secretion in response to an oral challenge. Exendin-(9,39) a competitive antagonist of GLP-1, has been used to quantify the contribution of endogenous GLP-1 to glucose tolerance. In nondiabetic subjects, Exendin-(9,39) infused for three hours altered the subsequent β-cell response to an i.v. glucose challenge. Similar results were observed using perifused human islets from nondiabetic donors. We hypothesized that the effects of fasting GLP-1 secretion on β-cell response would be similar in people with type 2 diabetes (T2D). We studied 9 subjects with T2D in random order. Glucose containing [3-3H]-glucose was infused to mimic the systemic appearance of glucose after a meal. On one occasion, saline, was infused for 3 hours prior (-180 to 0 minutes) to the I.V. challenge, while on the other Exendin-(9,39) was infused at 750pmol/kg/minutes. Exendin-(9,39) infusion prior to the i.v. challenge increased fasting (8.7 ± 0.6 vs. 7.8 ± 0.5 mmol/l, p < 0.01) and peak (13.3 ± 0.8 vs. 12.5 ± 0.6 mmol/l, p = 0.05) glucose concentrations. These differences were not explained by altered insulin secretion: insulin and C-peptide concentrations did not differ between study days. On the other hand, fasting glucagon concentrations were increased (70 ± 8 vs. 53 ± 1 ng/l, p = 0.01) by Exendin-(9,39) and this was accompanied by increased endogenous glucose production (23 ± 1 vs. 20 ± 1 μmol/kg/minutes, p = 0.02). In separate experiments using perifused isolated human islets from diabetic donors, pretreatment with Exendin-(9,39) did not alter integrated insulin secretion in response to hyperglycemia (0.6 ± 0.2 vs. 0.9 ± 0.4 nmol/Islet/30 minutes, p = 0.49). Taken together these results suggest that in T2D fasting GLP-1 receptor activation may augment glucagon suppression in response to subsequent challenges. This may represent an adaptive mechanism not seen in nondiabetic subjects that restrains α-cell function to decrease postprandial hyperglycemia.

Disclosure

M.D. Hurtado: None. A.M. Egan: None. M.C. Laurenti: Employee; Self; GlySens Incorporated. J. Adams: None. R.A. Rizza: Advisory Panel; Self; Lilly Diabetes, Metavention, Novo Nordisk A/S, vTv Therapeutics. C. Cobelli: None. A. Matveyenko: None. C. Dalla Man: None. A. Vella: Advisory Panel; Self; vTv Therapeutics. Research Support; Self; Novo Nordisk Inc.

Funding

Endocrine Fellows Foundation; National Institutes of Health
184-LB: Pancreatic Hypoplasia Patients Experience Poor Weight Gain and Labile Diabetes without Diabetic Ketoacidosis (DKA)
Authors: DENSON ANNA M. , FREEMARK MICHAEL , THOMAS INAS H. , ABDULLATIF HUSSEIN , NOGUEIRA JANAINA B. , BENJAMIN ROBERT , LETOURNEAU LISA R. , NAYLOR ROCHELLE N. , GREELEY SIRI ATMA W.
Published: June 2019

Mutations in GATA6, GATA4 and PDX1 cause congenital diabetes and pancreatic hypoplasia (PH) or agenesis. We investigated clinical features and treatment of 10 PH patients through the University of Chicago National Monogenic Diabetes Registry. Data was self-reported or extracted from medical records. Similar to previous cohorts, congenital heart defects, gallbladder agenesis, and exocrine pancreatic insufficiency were often present, whereas features such as recurrent infections and epilepsy have not been reported previously (Figure 1). Weight gain and glycemic control were often poor, yet there were no episodes of DKA over 110 patient-years (Figure 2). Close multi-subspecialty follow-up of these complex patients may improve frequent difficulties with weight gain and highly labile blood sugars.

Disclosure

A.M. Denson: None. M. Freemark: Research Support; Self; Rhythm Pharmaceuticals, Inc. I.H. Thomas: None. H. Abdullatif: None. J.B. Nogueira: None. R. Benjamin: None. L.R. Letourneau: None. R.N. Naylor: None. S.W. Greeley: None.

Funding

American Diabetes Association (1-17-JDF-008 to S.A.W.G.); National Institutes of Health (R01DK104942, P30DK020595, UL1TR002389)
1867-P: The Role of Ketone Bodies in Diabetes Pathogenesis Using Untargeted Metabolomics
Authors: PUCHALSKA PATRYCJA , LENGFELD JUSTIN E. , STAGG DAVID B. , CRAWFORD PETER A.
Published: June 2019

The pathogenesis of human T2D is linked to the progression of nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH). In the normal fed state, impairments of hepatocyte ketogenesis and Kupffer cell mitochondrial metabolism of ketone bodies conspire to drive hepatic injury, and lobular fibrosis - key features increasing insulin resistance and T2D. Preliminary data suggest that a local circuit of intrahepatic ketone metabolism may protect the liver from lobular injury, which involves distribution of ketone body carbon into numerous metabolic pathways. Nonetheless, the metabolic products of local hepatic ketone body metabolism that confer protection to the liver, and which are therefore linked to insulin resistance and T2D, remain unknown. Here, we use stable isotope tracing untargeted metabolomics (ITUM) to reveal the chemical space penetrated in vivo by D-[13C]β-hydroxybutyrate (D-βOHB) and its oxidized redox partner [13C]acetoacetate (AcAc). A kinetic study revealed rapid clearance (∼30 min) of both ketones from the bloodstream when introduced as intraperitoneal boluses into wild type mice. Many 13C-labeled metabolites were tissue-specific, particularly distinctly acetylated amino acids. Labeling of TCA cycle intermediates by 13C-labeled ketone bodies also varied by tissue, and by the specific labeled ketone body delivered. Finally, recurrent administration of unlabeled AcAc protected mice from high fat, fibrogenic diet-induced hepatic injury and fibrosis, while unlabeled D-βOHB exacerbated injury and fibrosis.

In conclusion, the two ketone bodies AcAc and D-βOHB, strikingly exhibit distinct metabolic and phenotypic effects in the context of NAFLD/NASH, and insulin resistance.

Disclosure

P. Puchalska: None. J.E. Lengfeld: None. D.B. Stagg: None. P.A. Crawford: Consultant; Spouse/Partner; Medtronic.
1872-P: Hepatic miR-582-5p Is Programmed by Maternal Diet-Induced Obesity in Male Mice and Contributes to Nonalcoholic Fatty Liver Disease
Authors: PANTALEAO LUCAS , FERNANDEZ-TWINN DENISE , CARPENTER ASHA , LOCHE ELENA , DEARDEN LAURA , GUIMARAES DANIELLA DUQUE , PENFOLD NAOMI C. , ASHMORE THOMAS J. , BUSHELL MARTIN , OZANNE SUSAN
Published: June 2019

Obesity during pregnancy is associated with increased risk of nonalcoholic fatty liver disease (NAFLD) in the offspring; however, the underlying molecular mechanisms remain largely unknown. The aim of the current study was to explore the contribution of microRNAs (miRs) as mediators of programming by maternal obesity. To achieve this, we used a mouse model of maternal-diet induced obesity where dams develop gestational diabetes and offspring demonstrate increased hepatic triglyceride content. We carried out small RNA next generation sequencing analysis of liver from twelve-week-old male offspring and identified miR-582-5p as the most dysregulated, showing a threefold increase. Binding site prediction (TargetScan 7.2) and pathway enrichment analysis (Reactome v67) suggested a number of miR-582-5p target genes related to lipid metabolism including Insulin Induced Gene 2 (INSIG2) and Translocase of Inner Mitochondrial Membrane 23 (TIMM23). Overexpression of miR-582-5p in AML12 (mouse) and HEPG2 (human) cell lines caused increased triglyceride accumulation, downregulation of INSIG2 and TIMM23, increased nuclear localization of Sterol Regulatory Element-Binding Protein 1 (SREBP-1), and overexpression of lipogenic genes. These findings suggest that overexpression of miR-582-5p induces hepatic intracellular lipid accumulation through mechanisms that involve mitochondrial malfunction and activation of de novo lipogenesis. We therefore conclude that an epigenetically programmed increase in hepatic miR-582 is a likely contributing mechanism underlying the programming of fatty liver disease in the offspring of obese gestational diabetic mothers.

Disclosure

L. Pantaleao: None. D. Fernandez-Twinn: None. A. Carpenter: None. E. Loche: None. L. Dearden: None. D. Duque Guimaraes: None. N.C. Penfold: None. T.J. Ashmore: None. M. Bushell: None. S. Ozanne: Advisory Panel; Self; Nestlé.

Funding

Brazilian National Council for the Improvement of Higher Education (BEX 10594/13-2); Brazilian National Council for Scientific and Technological Development (PDE/204416/2014-0)
1882-P: Liver-Specific Deletion of the Mitochondrial Quality Control E3 Ligase Parkin Is Associated with Increased Hepatic Steatosis and Markers of NAFLD in Diet-Induced Obese Mice
Authors: EDMUNDS LIA R. , MILLS AMANDA , JURCZAK MICHAEL J.
Published: June 2019

PARKIN, an ubiquitin E3 ligase, regulates mitochondrial homeostasis through a process called mitophagy, where damaged mitochondria are selectively targeted and removed via autophagy. Diminished hepatic mitophagy may play a role in mitochondrial dysfunction that occurs alongside insulin resistance and hepatic steatosis in association with obesity. Reduced hepatic mitophagy was observed in obese mice with fatty liver, raising the question as to whether loss of mitophagy contributes to the pathogenesis of fatty liver or is merely associated with the disease. To understand how loss of hepatic mitophagy affects obesity-associated liver disease, we developed a liver-specific PARKIN knockout mouse (LKO). There was no difference in body weight in LKO compared with WT mice fed regular chow (RC) or high-fat diet (HFD; 60% kcal, 12 weeks). There was also no difference in liver steatosis between RC groups, however, liver steatosis was 45% greater in HFD-LKO compared with WT mice (p<0.05). Liver histology demonstrated presence of microvesicular steatosis in zones 2-3 in both HFD groups, but only LKO mice presented with micro and macrosteatosis in zones 1-3. HFD-LKO samples showed presence of an inflammatory cell infiltrate that was less apparent in WT samples. Unbiased transcriptomic analysis by RNA-Seq demonstrated 113 significant differentially expressed genes (82 up, 31 down) in HFD-LKO mice. Unsupervised gene ontology and pathway analysis revealed significant changes in extracellular matrix accumulation, lipid metabolism, metabolic and ROS processes in HFD-LKO mice.

In summary, the increased steatosis and presence of macrovesicular steatosis and inflammation in HFD-LKO mice, alongside changes in gene expression suggesting collagen deposition and extracellular matrix remodeling, suggest that loss of PARKIN-mediated mitophagy increases susceptibility to HFD and may predispose mice to NAFLD.

Disclosure

L.R. Edmunds: None. A. Mills: None. M.J. Jurczak: None.

Funding

American Diabetes Association (1-19-PDF-102 to L.R.E.)
1887-P: The GLP-1 Receptor Agonist Liraglutide Improves Hepatic Inflammation and Fibrosis in a Mouse Model of NASH
Authors: MONTANDON SOPHIE A. , SOMM EMMANUEL , VITO CLAUDIO DE , JORNAYVAZ FRANÇOIS R.
Published: June 2019

Nonalcoholic fatty liver disease (NAFLD) is a common complication of type 2 diabetes (T2D). In fact, NAFLD affects up to 70% of diabetic patients and 90-95% of obese individuals. NAFLD can progress to nonalcoholic steatohepatitis (NASH) which can itself lead to cirrhosis and hepatocellular carcinoma. Despite the life-threatening aspects of these hepatic disorders, validated pharmacologic treatments are still lacking. As GLP-1 receptor agonists (GLP-1 RAs) are now widely used in the treatment of T2D, our study aimed to assess their potential beneficial effects on NAFLD/NASH. Wild type C57BL/6 male mice were fed a methionine-choline deficient (MCD) diet to induce the liver manifestations of NASH (steatosis, hepatocyte ballooning, inflammation, fibrosis). After 3 weeks on MCD diet, mice were subcutaneously infused with either liraglutide (16 μg/d) or saline solution for 4 weeks using osmotic minipumps before being euthanazied for analysis. Liver tissues were studied using qPCR and histological stainings and pathological scores were evaluated by a certified pathologist. Liraglutide-infused mice had similar body and liver weights than saline controls. Histological scores revealed a significant decrease in hepatic inflammation in the liraglutide-infused mice compared to controls, despite a similar degree of steatosis. These observations were associated with a significant downexpression of profibrogenic genes (Col1a1, Col1a2, Col3a1, Timp1, Mmp13, Serpine1, Tgfb1) and inflammatory/immune markers (Tnfa, Itgax, Adgre1) in the liver of liraglutide-treated mice. In addition, genes involved in hepatic stellate cells activation (Acta1, Vim) were also downregulated in liraglutide-treated mice.

In conclusion, the long-acting GLP-1 RA liraglutide reduces liver inflammation and fibrosis despite no major action on steatosis. These results suggest anti-inflammatory and anti-fibrotic actions of liraglutide that are independent of lipid metabolism.

Disclosure

S.A. Montandon: None. E. Somm: None. C. De Vito: None. F.R. Jornayvaz: None.

Funding

Novo Nordisk
189-LB: Maternal Pharmacological Activation of PPAR-gamma or PPAR-alpha Differentially Affects Adiposity and Energy Metabolism in the Offspring of Rats Born to Mothers Subjected to Caloric Restriction during Pregnancy
Authors: VERONESI VANESSA B. , SANTOS-SILVA JUNIA C. , SOUZA DAILSON N. , JORDÃO TEIXEIRA CAIO , HECHT FERNANDA B. , TOBAR NATALIA , RODRIGUES PIOLI MARIANA , ANHE GABRIEL F.
Published: June 2019

Aims: Rats born to mothers subjected to caloric restriction (CR) during pregnancy and lactation exhibit reduced birth weight and adiposity in adult life. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that play important roles in adipocytes differentiation. The aim of our study is to evaluate if antenatal exposition PPAR-gamma (Pioglitazone) or PPAR-alpha (Gemfibrozil) activators are able to affect energy metabolism in the offspring born from rats subjected to RC during pregnancy and lactation.

Methods: Wistar rats were kept under CR from the 11th day of pregnancy until the 21st day after delivery. Pioglitazone (10mg/kg) or Gemfibrozil (90mg/kg) were offered during the period of CR (offspring were CR+Pio and CR+Gem, respectively). Adult female offspring were subjected to indirect calorimetry, thermal infra-red imaging of BAT, VLDL production assay and DEXA for body composition.

Results: The body weight in adult CR+Gem, but not in CR+Pio, was higher than that of offspring born to CR mother. CR+Pio had reduced energy expenditure (EE) and higher relative weight of the perigonadal and retroperitoneal fat pads. On the other hand, adult CR+Gem had no changes in EE and visceral adiposity when compared to RC but presented increased whole-body adiposity as revealed by DEXA analysis. Although hepatic triglycerides (TG) or VLDL production were not altered in offspring born to CR mothers and in CR+Pio, these parameters were downregulated in RC+Gem. Both RC+Pio and RC+Gem had reduced temperature of the interscapular brown adipose tissue when compared to CR.

Conclusion: Maternal activation of PPAR-gamma increases visceral adiposity and reduces EE in the offspring born to mothers subjected to CR during pregnancy. Maternal activation of PPAR-alpha instead, increased body weight and reduced hepatic steatosis of the offspring born to mother exposed to CR.

Disclosure

V.B. Veronesi: None. J.C. Santos-Silva: None. D.N. Souza: None. C.J. Teixeira: None. F.B. Hecht: None. N. Tobar: None. M. Rodrigues Pioli: None. G.F. Anhe: None.

Funding

Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo
1892-P: Hepatic Agpat5 Regulates Plasma Insulin in Obesity
Authors: ST. CLAIR SAMANTHA L. , BELISLE SABRINA L. , LEYVA JAIMES FERNANDA B. , LI ZHONGGANG , PARKS BRIAN
Published: June 2019

There is increasing need to understand the molecular mechanisms contributing to obesity and type 2 diabetes. Agpat5, 1-acylglycerol-3-phosphate O-acyltransferase 5, is a lipid acyltransferase that esterifies the SN2 position of lysophospholipids to produce phospholipids. We previously identified Agpat5 within a genome-wide significant quantitative trait locus (QTL) associated with plasma insulin levels after high fat feeding in a mouse genetic reference population. We validated the effect of Agpat5, showing in multiple mouse models that treatment with Agpat5 antisense oligonucleotide (ASO) reduces plasma insulin after high-fat feeding. To investigate the hepatic role of Agpat5, we developed a liver-specific Agpat5 knockout mouse model. After 12 weeks of high-fat feeding, liver-specific Agpat5 knockout mice have significantly reduced fasting plasma insulin relative to control mice. Additionally, liver-specific Agpat5 knockout mice have significantly reduced hepatic triglycerides and are protected from hepatic steatosis. Investigating the effect of Agpat5 on hepatic insulin resistance, we found that loss of Agpat5 improves insulin signaling and reduces Foxo1 protein levels. Our studies suggest that hepatic Agpat5 may serve as a link between lipid metabolism and insulin signaling to regulate plasma insulin in obesity. Thus, drug therapies targeting Agpat5 could be developed to treat type 2 diabetes in obese populations.

Disclosure

S.L. St. Clair: None. S.L. Belisle: None. F.B. Leyva Jaimes: None. Z. Li: None. B. Parks: None.

Funding

National Institutes of Health
1893-P: Impact of Lean Hepatic Volume on Hepatic Insulin Resistance in Human NAFLD
Authors: IGARASHI HIROYUKI , SHIGIYAMA FUMIKA , HIRUMA SHIGENORI , HIROSE TAKAHISA , KUMASHIRO NAOKI
Published: June 2019

Hepatic insulin resistance (H-IR) is a major pathogenesis of type 2 diabetes mellitus (T2DM) with nonalcoholic fatty liver disease (NAFLD). Due to pandemic obesity, in addition to reducing toxic lipids in the liver, searching for other factors that may regulate hepatic insulin sensitivity (H-IS) is inevitable in humans with NAFLD. To find such factors, we performed comprehensive assessment in the patients with NAFLD (n=36) aged 47.4±12.3, BMI 29.4±4.7 kg/m2, DM/non-DM 23/13, HbA1c 6.7±1.0% (mean±SD). We assessed putative biomarkers in blood and urine, body composition, tissue lipid content by 1H-MRS, tissue IS by hyperinsulinemic euglycemic clamp, hepatic histological scores and gene expressions using biopsies, and life styles. Furthermore, we developed a new magnetic resonance imaging analytic method that can exactly evaluate the whole liver volume, whole hepatic lipid volume, and whole hepatic lean volume. We performed single regression analysis between H-IS assessed by clamped % suppression of endogenous glucose production and all evaluated indices. As results, existence of diabetes, fasting plasma glucose, and HbA1c showed significant negative correlation with H-IS, while plasma adiponectin, muscle IS and adipose tissue IS showed significant positive correlation with H-IS. Interestingly, whole liver volume (cm3/m2) and lean hepatic volume (cm3/m2) corrected by body surface area showed negative correlation with H-IS (β=-0.02, -0.03 and p<0.05, <0.01, respectively), specifically in patients with T2DM. Finally, multiple regression analysis confirmed that lean hepatic volume is a negative factor for the H-IS (β=-0.02, p<0.05).

Conclusion: Through comprehensive assessment including our new whole hepatic volume evaluation, we first demonstrated that lean hepatic volume strongly associates with H-IR specifically in patients with T2DM. Not only hepatic volume control but quality control supported by adiponectin or other insulin-targeted organs is necessary for H-IS in humans with NAFLD.

Disclosure

H. Igarashi: None. F. Shigiyama: None. S. Hiruma: None. T. Hirose: None. N. Kumashiro: Speaker's Bureau; Self; Novo Nordisk Inc., Sanofi, Takeda Pharmaceutical Company Limited.

Funding

Japan Society for the Promotion of Science (26702032, JP17H02180)
1896-P: Effect of PNPLA3 I148M Genotypes on Palmitate-Induced Hepatic Inflammation and Apoptosis
Authors: CHEN YUNZHI , LIANG HUA , YAN XUE MEI , XU XIAO
Published: June 2019

Background: GWAS has revealed that rs738409 C>G patatin-like phospholipase domain-containing 3(PNPLA3) is strongly associated with nonalcoholic fatty liver disease(NAFLD), but the mechanism remains obscure. Our study aims to investigate differences in mechanism for genotypes of PNPLA3 I148M in palmitate-induced inflammation and apoptosis.

Method: We constructed point mutation PNPLA3 148 I/I,148 I/M 148 M/M HepG2 cell lines via CRISPR-associated (Cas) 9 system. Cells were exposed to palmitate to induce lipid accumulation. Oil red O staining was used to explore the lipid deposition. Levels of inflammatory and apoptotic factors were determined by real-time PCR and western blotting.

Result: Lipid accumulation was remarkably increased in cells induced by PA, it is remarkably higher in 148M/M cell than in 148I/I HepG2 cell (P<0.05 PA vs. BSA). Expression of apoptotic and inflammatory markers BIP, p-PERK, CHOP, p-JNK increased significantly in 148M/M and 148I/M hepG2 cells (P<0.05). Compared with 148I/I cells, The mRNA expression of TNF-α and IL-8 was higher in 148M/M hepG2 cells induced by palmitate.

Conclusion: Different genotypes of PNPLA3 I148M have different effects on PA-induced lipid deposition, PNPLA3 148M may play an important role in pathogenesis of NAFLD through ER stress CHOP and IRE1α-JNK pathway.

Disclosure

Y. Chen: None. H. Liang: None. X. Yan: None. X. Xu: None.
1903-P: Protective Effects of Linagliptin on Hepatic Steatosis in Mice Treated with Dual Inhibitor for Insulin Receptor and IGF-1 Receptor
Authors: OKUYAMA TOMOKO , SHIRAKAWA JUN , TERAUCHI YASUO
Published: June 2019

We previously reported that systemic inhibition of insulin receptor (IR) and IGF-1 receptor (IGF1R) by administration of OSI-906 (linstinib), a dual IR/IGF1R inhibitor, for a week induced glucose intolerance, hepatic steatosis, and lipoatrophy in mice. In this study, we investigated the effects of a DPP-4 inhibitor linagliptin on hepatic steatosis in OSI-906-terated mice (OSI mice). Eight-week-old C57BL/6 mice were administrated 45 mg/kg of OSI-906 or vehicle with or without 3 mg/kg of linagliptin for 7 days. Linagliptin did not influence on hyperinsulinemia elicited by OSI-906. On the other hand, linagliptin reduced plasma triglyceride levels in OSI mice. Linagliptin also improved OSI-906-induced hepatic steatosis without changes in visceral fat atrophy. Hepatic gluconeogenic gene expressions, such as G6Pase, PEPCK and PGC-1α, were elevated by the administration of OSI-906, and linagliptin had no significant effect on those gene expressions. OSI-906-induced hepatic steatosis showed no significant changes in gene expressions of fatty acid synthesis or inflammation, such as SREBP-1c, TNF-α and IL-6. We also performed hepatic quantitative proteomic and phosphoproteomic analysis in OSI-906- or linagliptin-treated mice. Linagliptin significantly upregulated 3 proteins and significantly downregulated 7 proteins in the liver of OSI mice (fold change >1.5, p<0.05). The phosphorylation of 102 proteins and 191 proteins were up- and down-regulated by linagliptin in OSI mice. Proteomic analysis indicated Mup20, Cyp2b10, Perilipin-2, and Sirt2 were modulated in the process of amelioration of hepatic steatosis by linagliptin. Taken together, linagliptin improved hepatic steatosis induced by IR and IGF1R inhibition via a previously unknown mechanism, except for gluconeogenesis, lipogenesis, or inflammation, suggesting the potential action of DPP-4 inhibitors for the treatment of hepatic steatosis under insulin resistant conditions.

Disclosure

T. Okuyama: None. J. Shirakawa: None. Y. Terauchi: Advisory Panel; Self; AstraZeneca, Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novo Nordisk A/S, Sanofi. Research Support; Self; Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp & Dohme Corp., Novartis Pharmaceuticals Corporation, Novo Nordisk A/S, Ono Pharmaceutical Co., Ltd., Sanofi, Shionogi & Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd. Speaker's Bureau; Self; Astellas Pharma Inc., AstraZeneca, Bayer Yakuhin, Ltd., Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novartis Pharmaceuticals Corporation, Novo Nordisk A/S, Ono Pharmaceutical Co., Ltd., Sanofi, Sanwa Kagaku Kenkyusho, Shionogi & Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd.
1909-P: The Platelet-Derived Growth Factor a—An Additional Pathophysiological Factor in Hepatic Steatosis and Fibrosis Development Both in Patients with Hepatitis C and Patients with Prediabetes
Authors: BLASLOV KRISTINA , MALES VISNJA KOKIC , KOKIC SLAVEN , KRULJAC IVAN
Published: June 2019

Insulin resistance (IR) represents one of the key regulatory mechanisms in the development of non - alcoholic fatty liver disease. It is a common hepatocyte injury in hepatitis C virus (HCV) infection and type 2 diabetes mellitus (T2DM). Higher plasma platelet-derived growth factor A (PDGF- A) concentration is associated with increased hepatic steatosis and fibrosis in T2DM. PDGFs are key regulators of the connective tissue formation and potent mitogens for hepatic stellate cells. We investigated whether there is an association between PDGF-A serum concentration, IR and HCV mediated hepatic steatosis and fibrosis. This cross-sectional study comprised 90 nondiabetic participants aged 47.11±1.54 years divided into 3 groups: HCV negative group with IR (HCV-/IR-, N=12), HCV positive group without IR (HCV+/IR-, N=34), HCV positive group with IR (HCV+/IR+, N=44). The fasting PDGF-A concentration was determined by enzyme-linked immunoadsorbent assay. Homeostatic Model Assessment of IR score over 1.64 was categorised as IR. Fibrosis and steatosis were evaluated by elastography. Steatosis severity accessed by Controlled Attenuation Parameter (p<0.001) had the mean value of 15.9 kPa in the HCV+/IR+ (p<0.001) revealing the highest value in HCV-/IR+ (296.5 dB/m) group. The PDGF-A concentration correlated positively with steatosis (r=0.341, p=0.007) and fibrosis (r=0.264, p=0.071). Both IR positive groups had higher PDGF-A compared to HCV+/IR- group (p=0.006). In accordance with more pronounced steatosis, the HCV-/IR+ group revealed the highest PDGF-A. Concentration of PDGF-A is associated with the severity of hepatic steatosis in HCV and non-HCV patients with IR; i.e., that PDGF-A could represent one of the key regulatory mechanisms in the pathway from hepatic steatosis towards fibrosis. These results provide better understanding of pathways that regulate fibrosis.

Disclosure

K. Blaslov: None. V. Kokic Males: None. S. Kokic: None. I. Kruljac: None.
1919-P: Regulation and Function of Bone Marrow Adipocytes in Osteogenesis and Hematopoiesis
Authors: ZHANG ZENGDI , HUANG ZAN , RUAN HAI-BIN
Published: June 2019

In the bone marrow stroma, skeletal stem cells (SSCs) and their derived stromal cells, osteoblasts and bone marrow adipocytes (BMAs) provide the niche microenvironment to support the self-renewal and differentiation of hematopoietic stem cells (HSCs). However, it’s still largely mysterious how the bone-fat balance is disrupted and whether marrow adiposity contributes to the skewed differentiation of HSCs toward myeloid over lymphoid cells. Here we showed that the O-linked β-N-acetylglucosamine (O-GlcNAc) modification on intracellular proteins determined the adipogenic vs. osteogenic differentiation of SSCs. Conditional deletion of O-GlcNAc transferase (OGT) in Osx1+ cells promoted BMA formation while impaired osteoblast development and bone ossification, which resulted in defective B cell development. To determine the role of BM adipokines in hematopoiesis, we selectively ablated Kit ligand (Kitl) in Osx1+ and Adipoq+ lineages. Both Osx1-Kitl KO and Adipoq-Kitl KO mice lost myeloid progenitors in BM and developed macrocytic anemia. Collectively, our data identified protein O-GlcNAcylation as a novel regulator of SSCs differentiation and demonstrated that BMAs are functionally essential for unperturbed hematopoiesis.

Disclosure

Z. Zhang: None. Z. Huang: None. H. Ruan: None.

Funding

National Institutes of Health
1930-P: Heterogeneity of Skeletal Muscle (SM) Insulin Resistance (IR) in Type 1 Diabetes (T1D)
Authors: WILLIAMS KATHERINE V. , SHAY CHRISTINA M. , PRICE JULIE , ORCHARD TREVOR J. , KELLEY DAVID
Published: June 2019

In addition to a severe deficiency of insulin secretory capacity, systemic IR has also been identified as contributing to the pathophysiology of T1D. This study was undertaken to examine the contribution of SM, the major site for insulin-stimulated glucose uptake, to the IR of T1D, and more specifically, the role of impaired glucose transport. During euglycemic insulin infusion, dynamic PET imaging of SM was done using [18F]fluorodeoxyglucose (FDG), the metabolism of which is restricted to transport/phosphorylation. PET images were co-registered with calf MRI to assess and compare FDG uptake (Patlak K) in soleus (SO) SM (largely oxidative, type 1 fiber) and in tibialis anterior (TA) SM (largely glycolytic, type 2 fiber) to determine the respective severity of IR in these two types of SM. Systemic IR was assessed as glucose disposal rate (GDR) during the clamps. Participants (n=10) with T1D with no evidence of coronary artery or renal disease were recruited from the Pittsburgh Epidemiology of Diabetes Complications (EDC) study, a 30-year prospective study of childhood onset T1D. Mean HbA1c in T1D was 7.6±1.3%. Nondiabetic healthy controls (n=13) of comparable age (40.4 years) and BMI (24.1 kg/m2) as the T1D group (43.1 years, 24.3 kg/m2) were studied. Systemic IR was evident in T1D, with GDR reduced by ∼25% (4.95 vs. 6.60 mg/kg-FFM, p=0.06). SM IR was clearly present in oxidative SO SM in T1DM, as values for K were reduced by nearly 50% (0.0075 vs. 0.0126 mL/cm3-minutes, p<0.01). Yet intriguingly, there was no evidence of IR in the glycolytic muscle TA in T1D (0.0077 vs. 0.0087 mL/cm3-minutes); K was not different in either muscle group in T1D, though K for SO was greater than in TA in controls. Systemic GDR correlated with both SO (r=0.59, p=0.003) and TA (0.54, p=0.007) FDG uptake (K). Our findings confirm systemic IR in T1D, indicate the contribution of impaired glucose transport/phosphorylation within SM to IR in T1D, and raise the novel hypothesis that SM IR in T1DM predominately involves oxidative type SM.

Disclosure

K.V. Williams: None. C.M. Shay: None. J. Price: None. T.J. Orchard: Consultant; Self; Boehringer Ingelheim International GmbH. D. Kelley: Consultant; Self; Kallyope, Regeneron Pharmaceuticals, Takeda Pharmaceutical Company Limited. Other Relationship; Self; Merck & Co., Inc.

Funding

National Institutes of Health (DK071487)