bluuebunny/crossref_metadata_2025_split huggingface dataset:
1772-P: Insulin Granule Biogenesis at the Golgi Requires a Metabolically-Regulated, Non-centrosomal Subpopulation of Microtubules
Authors: TROGDEN KATHRYN , WRIGHT CHRISTOPHER V. , GU GUOQIANG , KAVERINA IRINA 
Published: June 2019

Insulin undergoes biogenesis through the ER and Golgi, ultimately leading to packaging into vesicles that are secreted in response to glucose. The movement between these membranes and the process of budding from the Golgi are vital steps. Previous work has found a role for microtubules (MTs) in these processes in both pancreatic β-cells and other cell types. Here, we show that the last stages of this process are regulated by a specific subpopulation of MTs that are non-centrosomal. Their formation, or nucleation, at the Golgi membrane is regulated by a glucose signal-transduction pathway through cAMP and its effector EPAC2. This effect is especially pronounced during the first, rapid phase of insulin secretion, during which EPAC2 levels increase at the sites of their nucleation. Preventing new nucleation of this specific population dramatically affects the pipeline of insulin production, storage and release. There is an overall reduction of β-cell insulin content, and the remaining insulin becomes retained within the Golgi, likely because of stalling of insulin-granule budding. This diminished granule availability substantially effects the level of both basal and stimulated insulin secretion, though not the ratio between these levels during the first wave. Constant dynamic maintenance of this network is therefore critical for normal β-cell physiology. This is the first demonstration that the biogenesis of post-Golgi carriers, particularly large secretory granules, requires ongoing nucleation/replenishment of this network. We are further looking at the role of MTs in β-cell secretory activity in intact islets. We have observed that MTs promote β-cell heterogeneity by restricting secretion from a specific β-cell sub-population, where insulin release can be activated upon disruption of the entire MT network by the drug nocodazole.

Disclosure
K. Trogden: None. C.V. Wright: None. G. Gu: None. I. Kaverina: None.

Funding
National Institutes of Health (1F32DK117529-01A1)
1777-P: Acute Hyperbaric Oxygen (HBO) Treatment Increases Hepatic Insulin Sensitivity and Muscle Reactive Oxygen Species in Type 2 Diabetes
Authors: SARABHAI THERESIA , ANADOL-SCHMITZ EVRIM , KATSUYAMA HISAYUKI , MARKGRAF DANIEL F. , BUSCH LUCAS , GUTHOFF RAINER , SCHNEPPENDAHL JOHANNES , RODEN MICHAEL 
Published: June 2019

Diabetes mellitus type 2 (T2D) is characterized by insulin resistance of liver and skeletal muscle, which is at least partly due to impaired muscle mitochondrial function. Long-term HBO therapy, as applied for treating the diabetic foot syndrome, has been shown to improve blood glucose concentrations. To study the underlying mechanisms, we examined the short-term effect of HBO treatment on insulin sensitivity and mitochondrial oxidative capacity and production of reactive oxygen species (ROS) in a randomized, double blinded, placebo-controlled trial. Volunteers with type 2 diabetes (n=4; age 61±4 years; body mass index 30.2±2.2 kg/m2; HbA1c 7.0±0.7%) underwent two 2-hours sessions in a hyperbaric chamber of once with application of 100% oxygen (1.4 bar over atmospheric pressure [barO] for 20 min; HBO) and once with ambient air as placebo (21% oxygen; 1.4 barO; PLC). Tissue-specific insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamps with stable isotope dilution, while muscle oxygen fluxes were measured with high resolution respirometry. After HBO treatment, hepatic insulin sensitivity was higher (insulin-mediated suppression of endogenous glucose production: 69.7±0.1% vs. PLC 55.3±3.2%, p&lt;0.05), whereas peripheral insulin sensitivity was comparable (2.0±0.3 vs. 2.2±0.3 mg*kg-1*min-1, p=0.24). Muscle ROS production markedly increased after HBO (increase in ROS: 73±3% vs. PLC -14±5%; p&lt;0.005), while mitochondrial oxidative capacity only tended to be lower after HBO.
In conclusion, a single session of HBO treatment already improves hepatic insulin resistance and stimulates muscle ROS release, which may activate antioxidative defense, both of which could contribute to improved glycaemia upon chronic treatment.

Disclosure
T. Sarabhai: None. E. Anadol-Schmitz: None. H. Katsuyama: None. D.F. Markgraf: Research Support; Self; Sanofi. L. Busch: None. R. Guthoff: None. J. Schneppendahl: None. M. Roden: Advisory Panel; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Poxel SA, Servier. Board Member; Self; Eli Lilly and Company. Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Sanofi. Speaker's Bureau; Self; Novo Nordisk Inc.
179-OR: Low-Dose Dihydrotestosterone Lowers Lipogenic Master Regulator in Liver and Adipose Tissue from Female Mice
Authors: ANDRISSE STANLEY 
Published: June 2019

Hyperandrogenemia (HA) and insulin resistance (IR) are hallmarks of polycystic ovary syndrome (PCOS), a common endocrine disorder that affects 1 in 10 women. These hallmarks are also integral elements of nonalcoholic liver disease (NALFD), a disorder that is common in women with PCOS. Administering low dose dihydrotestosterone (DHT) induced a lean female mouse model with a PCOS-like phenotype, displaying IR and NAFLD. The molecular mechanism of HA-induced NAFLD has not been determined. We hypothesized that low dose DHT would interrupt hepatic lipid metabolism leading to NAFLD. To investigate the role of androgens on the master regulator of lipogenesis, sterol regulatory element-binding protein 1 (SREBP-1), we extracted white adipose tissue (WAT), liver, and skeletal muscle from wild type, control and low dose DHT female mice; and performed Western blot and real-time quantitative PCR (qRT-PCR) analysis of lipogenic intermediates of the tissue homogenates. Low-dose DHT lowered the active form of cytosolic SREBP1 in the liver and WAT compared to controls. Additionally, low-dose DHT lowered inactive SREBP1 in the liver. However, the condition did not alter the levels of the active and inactive forms of SREBP2 in the liver and WAT, though the active form was lowered in skeletal muscle. Further, p-ACC levels were unaltered in liver and WAT. FAS levels were unchanged in WAT and skeletal muscle. Taken together, our findings support the hypothesis that cytosolic SREBP1 decreased due to its translocation to the nucleus, where it regulates lipogenic protein levels. We speculate that low-dose DHT promotes the translocation of SREBP-1 from the cytosol to the nucleus to influence lipogenic gene expression leading to increased lipogenesis contributing to NAFLD.

Disclosure
S. Andrisse: None.
1795-P: Novel Techniques for the Analysis of Brain Chondroitin Sulfates in Rodents and Humans with Type 2 Diabetes
Authors: ALONGE KIMBERLY M. , LOGSDON ARIC , BANKS WILLIAM A. , KEENE C. DIRK , SCHWARTZ MICHAEL W. , GUTTMAN MIKLOS 
Published: June 2019

We recently reported that perineuronal nets (PNNs), which are chondroitin sulfate (CS) containing matrices that function to maintain synaptic integrity of key neurocircuits, are present in the hypothalamus of mice, rats and humans (Mizadeh et al, Nat Metabolism, 2019). AgRP neurons are among those enmeshed by PNNs in this brain area and excessive activation of these neurons is suggested to play a role in the pathogenesis of T2D. Our finding that PNNs are abnormal in the hypothalamus of T2D rodents offers a plausible link between brain mediated glucose-sensing dysfunction and T2D pathogenesis. PNN matrix stability correlates closely with the abundance of specific CS variants that constitute the PNN matrix, with an increase in 6S-CS promoting matrix destabilization. Traditional methods for CS-based ECM analysis in fixed brain tissues depend primarily upon IHC detection of CS-specific disaccharides, but this method is limited by cross-reactivity of CS-specific antibodies. Here we report the development and validation of two novel and quantitative biochemical methods for the in-depth compositional analysis of four biologically relevant CS-derived disaccharides present in rodent and human fixed brain tissue: 1) electrospray ionization-tandem mass spectrometry (MS/MS) to determine the percentages of 4S- and 6S-CS within the monosulfated population, and 2) liquid chromatography (LC)-MS/MS for resolving and determining percentages of 0S- 4S- 6S- and 4S6S-CS. These methods can detect CS from fixed coronal brain slices with nanomolar sensitivity and high reproducibility. After optimization using synthetic standards, both methods were validated using a developmental time course series in fixed rodent brain tissue and then applied to the analysis of formalin-fixed human brain tissue. These methods offer a useful approach with which to investigate the role of aberrant CS composition in the pathogenesis of diabetes and related metabolic disorders.

Disclosure
K.M. Alonge: Research Support; Self; Novo Nordisk Inc. A. Logsdon: Research Support; Spouse/Partner; Novo Nordisk Inc. W.A. Banks: None. C. Keene: None. M.W. Schwartz: Consultant; Self; Novo Nordisk A/S. Research Support; Self; Novo Nordisk A/S. M. Guttman: None.

Funding
National Institutes of Health; Novo Nordisk
1808-P: Is There Evidence of Gliosis Outside the Mediobasal Hypothalamus in Obese Adults?
Authors: ROSENBAUM JENNIFER L. , MELHORN SUSAN J. , DE LEON MARY ROSALYNN , WEBB MARY , SCHUR ELLEN 
Published: June 2019

Data increasingly support evidence of gliosis in the mediobasal hypothalamus (MBH) in the setting of obesity and insulin resistance. It is if other regions of the brain are similarly affected. We tested if MBH gliosis is related to radiologic evidence of gliosis in selected subcortical, cortical, and hypothalamic regions.
We recruited 40 obese adults (aged 25-61 y), with variable glucose tolerance by OGTT (n=24 normal glucose tolerance, n=11 impaired glucose tolerance and n=5 with T2DM). Individuals underwent a multi-echo T2 brain MRI. Two analysts placed regions of interest (ROIs) on the scans and determined the T2 relaxation time as a measure of gliosis. ROIs included the MBH, amygdala, dorsomedial hypothalamus (DMH; area of the paraventricular nucleus), hippocampus, white matter (WM), cortex, caudate, ventral striatum (VS), and putamen. Left and right sides were averaged. High (n=13) and low (n=14) T2 groups were derived from the tertiles with the highest (strongest evidence for gliosis) and lowest T2 relaxation times. The groups were compared by linear regression adjusted for age and sex.
Mean BMI in the low T2 group was 35.7 ± 4.1 kg/m2 and high T2 group was 37.1 ± 4.9 kg/m2. The groups did not differ in T2 relaxation time of WM (P=0.29), cortex (P=0.15), caudate (P=0.49), putamen (P=0.79), amygdala (P=0.09), or hippocampus (P=0.44). In the high T2 group, T2 relaxation time was shorter in the VS (adjusted mean 80.9±2.9 vs. 83.1±3.0, P=0.04) and longer in the DMH (adjusted mean 108.9±5.3 vs. 103.7±5.4, P=0.02), compared to the low T2 group. When subjects with T2DM (n=1 in low and n=3 in high T2 group) were excluded, the differences were attenuated (VSP=0.13; DMHP=0.10).
The findings reveal preliminary evidence of longer T2 relaxation times in the DMH of obese individuals with signs of MBH gliosis and no evidence for gliosis in cortical or subcortical regions. Further study of gliosis in the DMH and its relation to blood glucose control and autonomic function in humans, particularly in those with T2DM, is warranted.

Disclosure
J.L. Rosenbaum: None. S.J. Melhorn: None. M. De Leon: None. M. Webb: None. E. Schur: None.

Funding
American Diabetes Association (1-17-ICTS-085 to E.S.); National Institutes of Health (T32HL007028); University of Washington Institute of Translational Health Sciences (UL1TR002319)
1820-P: Autonomic Tone Is Necessary for Bile Acid-Induced Hepatic Insulin Resistance
Authors: SYRING KRISTEN , MIGNEMI NICHOLAS A. , MCGUINNESS OWEN P. 
Published: June 2019

Diabetes and obesity cost the American healthcare system in excess of $322 billion dollars annually. Currently, one of the most effective treatments for obesity and metabolic disorders is bariatric surgery. Bariatric surgery leads to almost immediate metabolic benefits, independent of weight loss. Concurrent with the metabolic benefits, an elevation in systemic bile acids is also detected in these patients. Several investigations posit that the rise in systemic bile acids contributes to, or potentially drives, the beneficial outcomes described in these patients; however, the mechanism and direct effects of increased bile acids must be more thoroughly elucidated. Previous studies indicate that not only does the autonomic nervous system impact insulin action, but it also plays a role in bile acid synthesis and secretion. Specifically, studies in humans show that autonomic blockade in insulin resistant subjects leads to improved insulin sensitivity. Furthermore, in rats, a vagotomy results in increased serum bile acids concentrations. Prior data from our group demonstrates that during hyperinsulinemic-euglycemic clamps, increased circulating bile acids induce hepatic insulin resistance, resulting in a decrease in glucose infusion rates (GIR) (10±3 mg/kg/min) compared to control mice (21±4 mg/kg/min). Together these data led to the hypothesis that bile acids signal indirectly via the nervous system to impair hepatic insulin action. To test this hypothesis, autonomic tone was inhibited by infusion of a ganglionic blocker combined with an infusion of an alpha agonist to maintain blood pressure during clamps. In the presence of ganglionic blockade, bile acids do not induce hepatic insulin resistance. Instead, bile acid-treated mice have an increased GIR (66±3 mg/kg/min) compared to control mice (45±5 mg/kg/min). From these data we conclude that the autonomic nervous system is necessary for elevated systemic bile acids to impair insulin action in lean animals.

Disclosure
K. Syring: None. N.A. Mignemi: None. O.P. McGuinness: None.

Funding
National Institutes of Health
1849-P: Importance of Insulin’s Direct and Indirect Effects on Postprandial Hepatic Glucose Uptake
Authors: EDGERTON DALE S. , KRAFT GUILLAUME , FARMER BEN , SMITH MARTA S. , WILLIAMS PHILLIP E. , CHERRINGTON ALAN D. 
Published: June 2019

In heathy individuals the liver is a primary site of glucose disposal, it is in a state of glucose uptake most of the day, and this process is impaired in diabetes. Insulin stimulates hepatic glucose uptake (HGU) but the importance of its indirect effects (at fat, brain and pancreatic alpha cells) in driving HGU is unclear. Thus, the aim of this study was to determine the impact of insulin’s indirect mechanisms of control of HGU. Postprandial conditions were simulated for 4-hour in conscious dogs (n=7/group) by infusing somatostatin, intraportal insulin (1.8 mU/kg/min) and glucose (4 mg/kg/min), and leg vein glucose (to clamp arterial glucose at 2-fold basal). In one group insulin’s direct and indirect effects on the liver were both present (D+I) while in the other insulin’s indirect effects were blocked (D-only). In D+I the basal intraportal glucagon infusion rate was decreased to create a progressive decline in glucagon over time, FFA levels were allowed to fall, and brain insulin action was allowed to increase. In D-only glucagon and FFA levels were maintained at basal levels by infusions of intraportal glucagon and leg vein lipid emulsion. Hypothalamic insulin action was blocked by 3rd ventricle infusion of an insulin receptor antagonist. In the D+I and D-only groups, respectively, hepatic insulin increased during the experimental period (from 20±3 to 88±8 and 21±3 to 89±8 µU/ml), hepatic glucagon fell or remained basal (39±5 to 24±3 and 40±6 to 41±2 pg/ml) and arterial FFA fell or remained basal (1069±19 to 99±23 and 1195±63 to 998±99 µmol/l). HGU and net hepatic glucose uptake (NHGU) were independently measured using tracer and cold glucose balance techniques. The AUCs for HGU and NHGU (mg/kg/240 min) in D+I were 841±143 and 792±105, respectively, and 738±130 and 698±58 in D-only (P=0.6 and 0.4 between groups, respectively). Thus, in the healthy animal, HGU responds normally to insulin even in the absence of the hormone’s indirect effects. Instead HGU is driven almost exclusively by insulin’s direct effects.

Disclosure
D.S. Edgerton: Speaker's Bureau; Self; Novo Nordisk A/S. G. Kraft: Consultant; Self; Metavention. B. Farmer: None. M.S. Smith: None. P.E. Williams: None. A.D. Cherrington: Board Member; Self; Biocon, Fractyl Laboratories, Inc., Metavention, Sensulin, LLC., vTv Therapeutics, Zafgen, Inc. Consultant; Self; Abvance, Boston Scientific Corporation, California Institute for Biomedical Research, Galvani Bioelectronics Limited, MedImmune, Novo Nordisk Inc., Thetis Pharmaceuticals LLC. Research Support; Self; Abvance, Diasome Pharmaceuticals, Inc., Novo Nordisk Inc. Stock/Shareholder; Self; Abvance, Biocon, Fractyl Laboratories, Inc., Metavention, Novo Nordisk Inc., Sensulin, LLC., Thetis Pharmaceuticals LLC, Zafgen, Inc.

Funding
National Institutes of Health
1850-P: Bromocriptine (B) plus Curcumin (C) Synergize to Reduce Nonalcoholic Steatohepatitis (NASH) in Mice
Authors: TSAI TSUNG-HUANG , CINCOTTA ANTHONY 
Published: June 2019

NASH involves a combination of hepatic and gastrointestinal (GI) pathophysiologies comprising hepatic lipotoxicity and nitro/oxidative stress and a “leaky," proinflammatory GI environment that collude to induce the disease. B, a dopamine D2 receptor agonist is known to reduce plasma hyperFFAemia, and hepatic lipogenesis and inflammation. C has been demonstrated to reduce GI inflammation and leakiness, and is known to augment brain dopaminergic activity. We therefore investigated if B and C combination therapy that engages different pathological targets of NASH may provide an additive/synergistic benefit for NASH in a mouse model. C57B6 mice were maintained on 40 kcal% fat diet with 5% fructose drinking water for 20 weeks to induce NASH with fibrosis then randomized to 4 treatment groups: Vehicle, B (10mg/kg), C (100mg/kg), and combination of B and C (BC) (N=8/gr) daily for 4 weeks while maintained on the diet. A group of mice on normal diet was used as normal reference control. BC treatment led to significant reductions of hyperglycemia (21.8%), microbiome dysbiosis (38.1%), serum ALT (26.5%), obesity (10.1%), and liver steatosis (66.7%), inflammation (93.3%), ballooning (85.0%), NAFLD activity score (80.0%), as well as of four gene expression markers each of fibrosis (αSMA, TGFβ, COL1A, TXNIP) by 26-40%, inflammation (TNFa, IL1β, MCP1, iNOS) by 41-81%, ER stress (DDIT3, ATF, sXBP1, HSPA5) by 28-40%, steatosis (SREBP1c, FASN, ACC1, PLIN2) by 28-42%, and fatty acid oxidation (PPARα, PGC1α, CPT1, UCP1) by 24-84% and increased antioxidant gene expression (NQO, GPX1, CAT, HMOX1) by 29-70%, and reduced the percent fibrosis area by 80% relative to vehicle (and resultantly similar to normal diet mice) (all above: P&lt;0.05) and by amounts greater than either B or C alone or additively. This is the first study to demonstrate the positive interactive effects of bromocriptine and curcumin on NASH in a mouse obesogenic dietary model of the disease and it offers a potential safe means of treating NASH.

Disclosure
T. Tsai: Employee; Self; VeroScience LLC. A. Cincotta: Employee; Self; VeroScience LLC.
1853-P: Transforming Growth Factor Beta 1 Acts as a Hepatokine in Control of Glucose and Energy Metabolism
Authors: PAN QUAN , CHEN YUNMEI , KIM DA MI , SHEN ZHENG , YANG WANBAO , LI XIAOPENG , SUN YUXIANG , GUO SHAODONG 
Published: June 2019

Liver and adipose tissue are crucial for blood glucose and energy homeostasis, while impaired regulation of hepatic glucose production (HGP) and energy expenditure contribute to hyperglycemia and excessive fat storage in type 2 diabetes mellitus. Hepatokines are proteins secreted by hepatocytes, and several hepatokines have been shown to directly affect glucose and energy expenditure. In this study, we investigated the role of transforming growth factor beta 1 (TGF-β1) in hepatocytes in regulating glucose and energy homeostasis. We generated the liver-specific TGF-β1 knockout mice and found that the mice exhibited lower blood glucose, increased hepatic insulin sensitivity compared with wild type (WT) control mice. Using the mouse primary hepatocytes, we found that TGF-β1 deletion impaired HGP and TGF-β1 treatment promoted protein kinase A (PKA) signaling and stimulated the nuclear translocation of FoxO1. Under high fat diet (HFD) treatment, hepatic TGF-β1 deficiency protected mice from HFD-induced obesity and insulin resistance, decreased HGP and improved energy expenditure. Moreover, we used hepatic insulin receptor substrate-1, 2 (IRS1, 2) knockout (DKO) mice and deleted the TGF-β1 gene in the liver of DKO mice. We found that hepatic TGF-β1 ablation prevented hyperglycemia and hyperinsulinemia in DKO mice. Deletion of TGF-β1 or neutralization of TGF-β1 with antibody significantly decreased HGP of DKO hepatocytes. Additionally, hepatic TGF-β1 ablation enhanced thermogenesis and inguinal white adipose tissue (iWAT) browning in DKO mice. These findings underscore an important role of hepatic TGF-β1 in contribution to systemic glucose and energy homeostasis. Thus, hepatic TGF-β1 may serve as a therapeutic target for control of glucose and energy homeostasis in insulin resistance and type 2 diabetes mellitus.

Disclosure
Q. Pan: None. Y. Chen: None. D. Kim: None. Z. Shen: None. W. Yang: None. X. Li: None. Y. Sun: None. S. Guo: None.

Funding
American Diabetes Association (1-15-CD-09 to S.G.)
186-LB: Predictors of Diabetes Complication Screening at Two Years from Diagnosis in an Incident Cohort
Authors: AULICH JULIANE , CHAN ALBERT K. , CUSUMANO JANINE , PRYKE ALISON , BENITEZ-AGUIRRE PAUL Z. , CRAIG MARIA E. , DONAGHUE KIM C. 
Published: June 2019

Background: Despite well-established national complication screening programmes for patients with diabetes, complication rates in young adults with type 1 diabetes (T1D) remain high and uptake of screening unclear. It is important to determine risk factors that restrain newly diagnosed patients from attending the health care services.
Methods: Our incident cohort included all 1832 patients who were diagnosed with T1D younger than 16 years of age between 1990 and 2009 at the Children's Hospital at Westmead, Sydney, NSW. Median age at diagnosis was 8.8 years [5.5-11.6] and 51% were female. Data was analysed from all their documented visits at our clinic between 1st January 1990 and 22nd February 2017 including personal data, clinical variables, blood tests. DCAS attenders (67%) were compared to non-DCAS attenders (34%) for: BMI, HbA1c and socioeconomic disadvantage (SES) which was based on postal codes of Australian Bureau of Statistics.
Results: Comparing non-DCAS attenders with DCAS attenders, diabetes clinic attendance in the first 2 years was 1.7 vs. 2.5 times per year (p&lt;0.001), with a significant difference in their median HbA1c (7.9 vs. 8.0%, p=0.03) over this time, but no difference in BMI at 2-years. The difference in median lifetime HbA1c was even more significant (8.1 vs. 8.3%, p=&lt;0.001). DCAS attenders continued in the Diabetes Service for a mean of 9.1 years whereas the non-DCAS attenders were followed for 3.8 years (p&lt;0.001). 40% of the non-DCAS group were socio-economical disadvantaged compared to only 23% of the DCAS group (p&lt;0.001). In multivariable analysis, DCAS attendance was associated with more visits in clinics over the first 2 years, less SES and higher median lifetime HbA1c.
Conclusions: SES and less frequent clinic attendance in the first 2 years after diagnosis but not obesity, were predictors of non-uptake of complication screening and are likely to influence the outcome of T1D for these patients. It remains unclear if the non-attenders had medical follow-up at other services.

Disclosure
J. Aulich: None. A.K. Chan: None. J. Cusumano: None. A. Pryke: None. P.Z. Benitez-Aguirre: None. M.E. Craig: None. K.C. Donaghue: None.