bluuebunny/crossref_metadata_2025 huggingface dataset:
305-LB: BRD7 Deficiency Leads to the Development of Obesity
Authors: LEE JUNSIK M. , KIM YOO , SALAZAR HERNANDEZ MARIO A. , PARK SANG
Published: June 2019

Elevated endoplasmic reticulum (ER) stress is tightly associated with the development of obesity and insulin resistance. Previous reports showed that haploinsufficiency of X-box binding protein 1 (XBP1), one of the master regulators of ER protein folding function, results in obesity and type 2 diabetes. In our previous work, we showed that bromodomain-containing protein 7 (BRD7) regulates the nuclear translocation of XBP1 through its interaction with the regulatory subunits of phosphatidylinositol 3 kinase (PI3K), p85s. We reported that the expression levels of BRD7 are significantly reduced in the liver of obese mice and acute upregulation of hepatic BRD7 in obese and type 2 diabetic mice improves glucose homeostasis. In our current unpublished work, we show that nuclear translocation of BRD7 is independent of PI3K activity and p110, the catalytic subunit of PI3K, is not involved in the degradation of BRD7. We show that both whole-body reduction and liver-specific deletion of BRD7 lead to increased weight gain. We also show that sustained restoration of BRD7 in the liver starting at an early age protects mice from developing obesity, glucose intolerance, and insulin resistance even when challenged with a high-fat diet.

Disclosure

J.M. Lee: None. Y. Kim: None. M.A. Salazar Hernandez: None. S. Park: None.

Funding

American Diabetes Association (1-17-IBS-104 to S.P.); National Institutes of Health
306-LB: Adipocyte Subpopulations Mediate the Inflammatory Response in Adipose Tissue
Authors: LUONG QUYEN , HUANG JUN , SHARMA RITA , LEE KEVIN Y.
Published: June 2019

Recent studies suggest that, even within a single adipose depot, there may be distinct subpopulations of adipocytes. Our lab has uncovered three developmentally distinct subpopulations of white adipocytes. These adipocyte subpopulations have unique gene expression signatures, and display differential responses to exogenous stimuli including insulin, inflammatory cytokines, and insulin. These three adipocyte subtypes are distinguished by high expression of specific marker genes: Wilms’ tumor 1 (type 1), transgelin (type 2), and myxovirus 1 (type 3). Utilizing Cre transgenic mice, transcription of which is directed by the promoters of these marker genes, lineage tracing analysis indicate that these three preadipocyte subpopulations independently gave rise to adipocytes in vivo, and differentially contribute to the adipose tissue depots. During high fat diet (HFD) induced obesity, macrophages, organized into crown like structures (CLS) around dead and dying adipocytes, are detected in the vicinity of type 1 adipocytes, as assessed by kernel density estimation. This association between type 1 adipocytes and CLS is secondary to a ∼10-fold increase in the expression of macrophage chemoattractant protein 1 at both the mRNA and protein level. Furthermore, although CLS are found in the vicinity of type 1 cells, with very few of the CLS are in direct contact with type 1 adipocytes. Instead, over 80% of CLS are found in direct contact with type 2 adipocytes, indicating an increased death of these adipocytes during HFD-induced obesity. Taken together, these data suggest that type 1 and type2 adipocytes coordinately regulate the inflammatory response in adipose tissue.

Disclosure

Q. Luong: None. J. Huang: None. R. Sharma: None. K.Y. Lee: None.

Funding

American Diabetes Association (1-17-JDF-055 to K.Y.L.)
314-OR: Mechanisms of AgRP Neuron-Induced Hunger
Authors: KNIGHT ZACHARY
Published: June 2019

Neural circuits express a remarkable diversity of neuropeptides, yet the specific function of most of these peptides remains unclear. Agouti-Related Peptide (AgRP) neurons in the arcuate nucleus are critical for the regulation of energy balance. These cells are activated by food deprivation and their activity promotes food seeking and consumption. When food is discovered, AgRP neurons are inhibited within seconds, yet their potentiation of feeding persists for tens of minutes. The mechanisms underlying this sustained hunger drive remain unknown. I will describe data showing that Neuropeptide Y (NPY) is uniquely required for the long-lasting effects of AgRP neurons on feeding behavior. We systematically blocked the ability of AgRP neurons to signal through AgRP, NPY, and GABA, and then stimulated these cells using an optogenetic paradigm that mimics their natural regulation. We found that genetic deletion of NPY abolished optically stimulated food intake and lever-pressing for food, whereas inactivation of AgRP or GABA signaling had no effect. Re-expression of NPY selectively in AgRP neurons rescued these deficits. These findings reveal that NPY plays a critical role in enabling AgRP neurons to drive feeding behavior, due its unique ability to sustain hunger in the interval between food discovery and consumption.

Disclosure

Z. Knight: None.

Funding

American Diabetes Association/Pathway to Stop Diabetes (1-16-ACE-29 to Z.K.); National Institutes of Health; Howard Hughes Medical Institute
321-LB: The Link between Obesity and Changes in Epigenetic Marks in Adipose Tissue—In Vivo Study
Authors: ALAMA ANETA , PAWE?KA DOROTA , MYSZCZYSZYN ANETA , MALODOBRA-MAZUR MALGORZATA
Published: June 2019

Obesity is a leading problem in modern civilization. It is also the main risk factor of metabolic disorders like insulin resistance or type 2 diabetes. Numerous studies indicate in obesity the aberrant profile of various genes expressions like insulin signaling, adipokines, and cytokines genes as well as transcription factors regulating adipocytes development and metabolism. One of the reasons that might lead to dysregulation in genes expression is epigenetic changes in chromatin. In our study, we compared the global and site-specific DNA methylation and histones modifications (activate expression: H3K4me3 and H3K9ac, responsible for chromatin repression: H3K9me3) between subcutaneous (SAT) and visceral (VAT) adipose tissue from patients in a wide range of BMI with equal distribution of sex and in similar age. We have displayed a slight difference between epigenetic marks between SAT and VAT of enrolled patients, however, when classified into two groups according to BMI (lean group <25 kg/m2 and obese group ≥25 kg/m2) the difference in analyzed epigenetic markers were major. We found that global DNA methylation was increased in the obese group compared to lean, both in SAT and VAT. What is more, a similar correlation occurs in the case of site-specific methylation. The increased methylation of CpG islands was observed within promotor of the two important genes - PPARγ and CEBPα, transcription factors that regulate numerous genes in adipocytes metabolism, including insulin pathway. The observed epigenetic modifications in obesity may suggest a role of epigenetic regulation in the development of obesity. In addition, in the obese group, apart from increased methylation within DNA, we also observed disorders in the level of expression of genes which are important for the metabolic pathway, including the insulin pathway. These results may suggest a potential mechanism with an epigenetic regulation basis, which is responsible for the coexistence of metabolic disorders with obesity.

Disclosure

A. Alama: None. D. Pawe?ka: None. A. Myszczyszyn: None. M. Malodobra-Mazur: None.

Funding

National Science Centre, Poland (2016/21/D/NZ5/00155)
325-LB: Circadian Clock Nuclear Receptor REV-ERBa Is a Novel Regulator of Beta-Cell Function, Survival, and Autophagy under Diabetogenic Conditions
Authors: COSTES SAFIA , LAOUTEOUET DAMIEN , RAVIER MAGALIE A. , DELOBEL MORGANE , BERTRAND GYSLAINE , DALLE STéPHANE , MATVEYENKO ALEKSEY
Published: June 2019

The circadian clock regulates diverse cellular and molecular rhythms employing CLOCK-BMAL1 transcriptional heterodimer with nuclear receptor REV-ERBα (encoded by gene Nr1d1) playing an important role as a clock repressor through modulation of Bmal1 transcription. Importantly, in addition to its core circadian clock function, recent studies have identified REV-ERBα as a potent transcriptional repressor of autophagy. Therefore, in the current study we set out to address whether impaired beta-cell function and survival associated with exposure to diabetogenic stressors (e.g., glucotoxicity and inflammation) is attributed in part to REV-ERBα-mediated inhibition of autophagy. Exposure of beta-cells (INS-1E cell line) to either glucotoxicity (30 mM glucose) or cytokines (cytomix of IL-1β, TNFα and IFNγ) resulted in robust induction of REV-ERBα expression (1.5-2 fold, p<0.05) and corresponded with impaired autophagy flux characterized by increased protein levels of p62 (also known SQSTM1) (1.5-2 fold, p<0.05). Consistent with these data, exposure of beta-cells to a REV-ERBα agonist (SR9011) was characterized by impaired autophagy (increased p62 levels and aggregated forms, p<0.05), defective glucose-stimulated insulin secretion (70% decrease) and increased beta-cell apoptosis (increased cleaved caspase-3, p<0.01 vs. vehicle). In contrast, REV-ERBα specific antagonist (SR8278) partly protected beta-cells from deleterious effects of glucotoxicity or cytokines-induced inflammation by enhancing autophagy flux and attenuating beta-cell apoptosis (∼30%). Taken together, these data reveal for the first time an underexplored link between the core circadian clock nuclear receptor REV-ERBα, autophagy and beta-cell failure under diabetogenic conditions. These data also suggest a therapeutic potential of modulating REV-ERBα levels in beta-cells to enhance function and survival in diabetes.

Disclosure

S. Costes: None. D. Laouteouet: None. M.A. Ravier: None. M. Delobel: None. G. Bertrand: None. S. Dalle: None. A. Matveyenko: None.
328-OR: Degree of Glycemic Improvement in Patients with Diabetes Enrolled in Real-World Intensive Lifestyle Intervention in Relation to Baseline A1C: Five-Year Longitudinal Observation
Authors: TASABEHJI MHD WAEL , TOMAH SHAHEEN , ASHRAFZADEH SAHAR , MOTTALIB ADHAM , HAMDY OSAMA
Published: June 2019

We previously reported that weight loss in patients with diabetes and obesity through real-world Intensive Lifestyle Intervention (ILI) is associated with significantly lower A1C for up to 5 years. However, it is unclear if baseline A1C has any impact on the magnitude of glycemic improvement in this population. Over 5 years, we evaluated a cohort of 129 patients with diabetes and obesity (90% type 2 diabetes, 67% female, mean age 53±10 years, diabetes duration 10±9 years, body weight 110±19 Kg, BMI 38±5.3 Kg/m2) enrolled in a 12-week ILI program. According to baseline A1C, we divided participants into group A with A1C<7.5% (73 patients, 56.6%, mean A1C 6.5±0.5%), group B with A1C 7.5-9% (41 patients, 31.8%, mean A1C 8.1±0.4%), and group C with A1C >9% (15 patients, 11.6%, mean A1C 9.8±0.8%). Compared to baseline, body weight decreased at 5 years by 6.6 Kg, 9.6 Kg, and 8.3 Kg in groups A, B, and C, respectively (p<0.05 for all). A1C in group A decreased by 0.5±0.9% at 12 weeks (p<0.0001) but increased over the following 5 years by 0.1±0.1%, 1.2±0.9%, 0.3±0.1%, 0.4±0.1%, and 0.6±0.2%, respectively (p<0.01 at 5 years compared to baseline). A1C in group B decreased by 1.1±0.2% at 12 weeks (p<0.0001), was maintained significantly lower at 1 year by -0.5±0.2% (p<0.001), rose to baseline at 3 years and maintained at the same level for up to 5 years. A1C in group C decreased by 2.4%±0.3% at 12 weeks (p<0.0001), was maintained significantly lower at 1 year by 0.9±0.5% (p<0.001), also rose to baseline at 3 years, and was maintained at the same level for up to 5 years (p<0.05 between groups at 5 years). We conclude that patients with diabetes and obesity who enroll in real-world ILI with baseline A1C ≥7.5% are more likely to maintain improvements in A1C for at least 3 years before returning to baseline values compared to patients with baseline A1C<7.5%. This finding may help clinicians use baseline A1C to set realistic long-term expectations for patients considering ILI.

Disclosure

M. Tasabehji: None. S. Tomah: Stock/Shareholder; Self; Amarin Corporation. S. Ashrafzadeh: None. A. Mottalib: None. O. Hamdy: Advisory Panel; Self; AstraZeneca, Sanofi-Aventis. Consultant; Self; Abbott, Merck & Co., Inc. Research Support; Self; National Dairy Council. Stock/Shareholder; Self; Healthimation, LLC.
329-LB: Exocrine Pancreas Proteases Are Drivers of ß-Cell Proliferation
Authors: HOSTELLEY TIMOTHY L. , DUNLEAVEY JESSICA , LARKIN EMILY J. , JONES AMANDA J. , BOYES DANIEL L. , FONTAINE MAGALI J. , ZAGHLOUL NORANN A.
Published: June 2019

The clinical link between loss of β-cell mass and diabetes susceptibility provides a promising avenue of research for novel therapeutics targeting the proliferative axis. To identify potential new pathways involved we utilized two zebrafish genetic models Alström Syndrome (AS) and Bardet-Biedl Syndrome (BBS) that exhibit strikingly different diabetes rates, ∼75% in AS and ∼4% in BBS. We have previously shown β-cell loss in AS and increase in BBS, corresponding to their diabetes rates. RNA-Sequencing of these models identified several exocrine pancreas proteases that were differentially expressed between AS and BBS. Thus, we hypothesized that the exocrine pancreas proteases affect endocrine pancreas function. To test our hypothesis, we overexpressed each enzyme in transgenic zebrafish embryos in which β-cells can be visualized. In control animals, overexpression of exocrine pancreas proteases significantly increased the β-cell number. Overexpression rescued the loss of β-cells observed in animals depleted of alms1. We found ctrb1 overexpression led to increased β-cell proliferation in transgenic larvae and rescued the AS model reduction in proliferation. To test for endogenous protease uptake, we generated a transgenic GFP-tagged CTRB1 and found that 10% of β-cells were GFP+, suggesting a direct interaction between the exocrine and endocrine pancreas. We also found that the inactive, zymogen, form of these enzymes are taken up by β-cells in vitro and induce proliferation in cultured MIN6 β-cells and freshly isolated ex vivo islet cultures, suggesting this effect is conserved in mammalian systems. These data support an important role for exocrine pancreatic enzymes in the modulation of β-cells in diabetes.

Disclosure

T.L. Hostelley: None. J. Dunleavey: None. E.J. Larkin: None. A.J. Jones: None. D.L. Boyes: None. M.J. Fontaine: None. N.A. Zaghloul: None.

Funding

National Institutes of Health (F31DK115179-01A1, T32DK098107, R01DK102001, R25GM055036)
329-OR: Shared Medical Appointments (SMA) with Weight Management vs. SMA Alone for Overweight or Obese Patients with Type 2 Diabetes
Authors: YANCY WILLIAM S. , COFFMAN CYNTHIA , CROWLEY MATTHEW , DAR MOAHAD , JEFFREYS AMY S. , MACIEJEWSKI MATTHEW L. , VOILS CORRINE I. , BARTON ANNA E. , EDELMAN DAVID
Published: June 2019

Background: Shared medical appointments (SMA) improve outcomes in diabetes. SMAs often address lifestyle but infrequently lead to weight loss. Because weight loss reduces glycemia and medication use, we hypothesized an SMA intervention with weight management (WM/SMA) would be non-inferior for glycemic control and superior for patient-centered outcomes versus SMA alone.

Methods: In a 48-week, randomized trial with primary outcome of HbA1c (non-inferiority margin 0.5%), we recruited outpatients with uncontrolled T2DM and BMI ≥27 from two Veterans Health Administration sites. WM/SMA participants received baseline medication reduction and low-carbohydrate diet counseling with medication optimization every 2 weeks for 16 weeks, then an abbreviated SMA intervention every 8 weeks. SMA participants received group counseling on diabetes-related topics with medication optimization every 4 weeks for 16 weeks, then every 8 weeks. HbA1c, diabetes medication effect score (MES) and hypoglycemic events were analyzed using linear mixed models.

Results: In 263 participants, baseline mean age was 61, HbA1c 9.1% and BMI 35.3; 10.6% were women and 54.4% were black. At 48 weeks, HbA1c decreased 0.9% for WM/SMA and 0.8% for SMA (mean difference -0.1%, 95% CI -0.5, 0.3; non-inferiority criterion met), and decreased more with WM/SMA than SMA alone at interim weeks 16 (-0.7%, 95% CI -1.0, -0.4) and 32 (-0.5%; 95% CI -0.8, -0.2). At 48 weeks, diabetes medication use was lower in the WM/SMA than SMA group (mean difference in MES -0.5, 95% CI -0.6, -0.3; p<0.0001). WM/SMA participants had 51% fewer hypoglycemic events than SMA participants over 48 weeks (Incident Rate Ratio=0.49; 95% CI 0.27, 0.71; p<0.001).

Conclusion: Compared with conventional SMA-based medication management for patients with T2DM, SMA with intensive low-carbohydrate diet counseling yielded similar glycemic control while improving hypoglycemia and decreasing medication burden.

Disclosure

W.S. Yancy: None. C. Coffman: None. M. Crowley: None. M. Dar: None. A.S. Jeffreys: None. M.L. Maciejewski: Employee; Spouse/Partner; Amgen Inc. Stock/Shareholder; Spouse/Partner; Amgen Inc. C.I. Voils: None. A.E. Barton: None. D. Edelman: None.

Funding

U.S. Department of Veterans Affairs
337-LB: Combined Oral Administration of GABA and GLP-1 Promotes Human ß-Cell Proliferation and Reduces Apoptosis
Authors: LIU WENJUAN , JIN TIANRU , WANG QINGHUA
Published: June 2019

Gamma-aminobutyric acid (GABA) and glucagon-like peptide-1 (GLP-1) improve rodent β cell survival and function. In human β cells, GABA exerts stimulatory effects on proliferation and anti-apoptotic effects, whereas GLP-1-based drugs have only limited effects on proliferation. We previously demonstrated that GABA and sitagliptin, a dipeptidyl peptidase-4 inhibitor which increases endogenous GLP-1 levels, mediated a synergistic β cell protective effect in mice islets. However, it remains unclear whether this combination has similar effects on human β cells. To address this question, we transplanted a suboptimal mass of human islets into immunodeficient NOD-scid-gamma mice with streptozotocin-induced diabetes, and then treated them with GABA, sitagliptin, or both. The oral administration of either GABA or sitagliptin ameliorated blood glucose levels, increased transplanted human β cell mass and plasma human insulin levels. However, combined administration of the drugs generated significantly superior results in all these responses, as compared to monotherapy. Proliferation and/or regeneration, improved by the combination, were demonstrated by increased Ki67+, pancreatic and duodenal homeobox-1 (PDX-1+), or Nkx6.1+ β cell numbers. Protection against apoptosis was also significantly improved by the combined therapy. GABA and GLP-1 in combination notably increased Akt phosphorylation and insulin secretion, as well as the expression of sirtuin-1 and α-Klotho, both of which have been reported to have protective effects on β-cells. Our study indicates that combined use of GABA and sitagliptin produced greater therapeutic benefits, which was likely due to an enhancement of β cell proliferation and a decrease of apoptosis.

Disclosure

W. Liu: None. T. Jin: None. Q. Wang: None.

Funding

National Natural Science Foundation of China (81570518, 81630020); JDRF (2-SRA-2017-64-G-R to Q.W., T.J.), (2-SRA-2015-64 to Q.W., T.J.); Canadian Diabetes Association (OG-3-13-4066 to Q.W.)
339-OR: Yo Puedo! A Self-Management Group and mHealth Program for Low-Income Adults with Type 2 Diabetes in Mexico City
Authors: WHITTEMORE ROBIN , VILAR-COMPTE MIREYA , LA CERDA SELENE DE , DELVY ROBERTA , JEON SANGCHOON , BURROLA-MÉNDEZ SORAYA I. , LOZANO-MARRUFO ANNEL A. , PEREZ-ESCAMILLA RAFAEL
Published: June 2019

The purpose of this study was to evaluate the preliminary efficacy of a self-management group + mHealth program (Yo Puedo!) on clinical (A1C, BP, BMI), self-management (diet, exercise, blood glucose monitoring), depressive symptom, and self-efficacy outcomes in adults with type 2 diabetes (T2D) at Seguro Popular clinics in Mexico City. Participants were randomly assigned to treatment (n=26) or wait-list control groups (n=21) with data collected at 3 and 6 months. The Yo Puedo! Program included 7 weekly sessions and 6 months of daily text messages. Descriptive statistics and generalized linear mixed model (GLMM) with random intercept were calculated. Adults with T2D were 55.5 years of age (±8.6), 68% female, 59% married/partnered, 88.6% overweight/obese, 50% lived in moderate/severe food insecure households, 35.7% had increased depressive symptoms, and 80% had A1C above 7.0%. Mean duration of T2D since diagnosis was 11.5 years (±7.1). There were no between-group differences on baseline characteristics. There was 89% attendance at sessions and 6% attrition at 6 months. Group by time effects were seen in blood glucose monitoring (p<.01), diabetes self-efficacy (p<.04); with a trend for lower A1C in the intervention group at 6 months (-1.76% in treatment group vs. -.97 in control group, p=.08). Time effects for the intervention group included improved diet, exercise, blood glucose monitoring, diabetes self-efficacy, depressive symptoms and A1C at 6 months (p<.05). Adults with T2D in Mexico City positively responded to the Yo Puedo! group + mHealth program with improvements in self-management, depressive symptoms, self-efficacy, and A1C. Empowering patients with T2D self-management skills can improve key behaviors, mental health and blood glucose outcomes in vulnerable populations. A fully powered clinical trial is warranted.

Disclosure

R. Whittemore: None. M. Vilar-Compte: None. S. De La Cerda: None. R. Delvy: None. S. Jeon: None. S.I. Burrola-Méndez: None. A.A. Lozano-Marrufo: None. R. Perez-Escamilla: None.

Funding

National Institute of Nursing Research
340-LB: Optogenetic Control of a-Cell Electrical Activity and Glucagon Secretion in Intact Islets
Authors: MIRANDA CAROLINE A. , DOU HAIQIANG , TOLö JOHAN , TARASOV ANDREI I. , RORSMAN PATRIK
Published: June 2019

Glucagon, the body's main hyperglycemic hormone, is produced by α-cells of the islets of Langerhans. A fall in plasma glucose stimulates glucagon release and it acts by increasing hepatic glucose production. How glucose regulates glucagon secretion remains debated and both intrinsic and paracrine mechanisms have been proposed. The fact that glucagon secretion becomes dysregulated in diabetes warrants detailed studies of the cell physiology of its release. We generated mice that express the light-sensitive cation channel Channelrhodopsin-2 (ChR2) under the control of the proglucagon promoter in the α-cells. This allowed us to selectively depolarize the plasma membrane of α-cells within intact isolated islets (using 488 nm laser) and record membrane potential, cytoplasmic Ca2+ ([Ca2+]i) glucagon release in response to the optical activation. At low (1mM) glucose, optoactivation depolarized the α-cells, induced a transient increase in [Ca2+]i, decreased peak voltage of the action potentials (from -2±1mV to -11±1mV, n=5, p<0.01) and reduced glucagon secretion by 50%. At elevated glucose (6-20mM, which inhibited secretion by ∼50% relative that at 1 mM glucose), α-cell action potential firing persisted and optoactivation remained capable of depolarizing the α-cell but now without affecting action potential peal voltage. Under these conditions, optoactivation did not reduce glucagon secretion beyond the inhibition produced by high glucose alone. It was ascertained that optoactivation of α-cells did not affect insulin secretion. The data reinforce earlier reports that membrane depolarization (despite increasing [Ca2+]I and stimulating action potential firing) produces a paradoxical inhibition of glucagon secretion via reduced action potential height. We propose that further optogenetic studies represent a means for non-invasive interrogation of the complex regulation of glucagon secretion in intact pancreatic islets.

Disclosure

C.A. Miranda: None. H. Dou: None. J. Tolö: None. A.I. Tarasov: Employee; Spouse/Partner; Vaccitech Ltd, Oxford, UK. P. Rorsman: None.

Funding

Swedish Research Council
341-OR: An Individualized, Simple, Patient-Centered Carb Counting Tool
Authors: WITKOW SHULAMIT , LIBERTY IDIT F. , GOLOUB IRINA , KAMINSKY MALKA , OTTO OLGA , RABIA YONES ABU , HARMAN BOEHM ILANA
Published: June 2019

Aims: To introduce a simple carb counting tool (CC) in patients with type 1 diabetes mellitus (T1DM) making CC easy and accessible, overcoming barriers such as age, education, gender or tutoring language.

Methods: In a randomized control trial 82 patients (pts.) received either 1-the common CC guidance using calculation of insulin sensitivity (IS), Carb:insulin ratio (C:I) or 2- a simple personalized tool consisting of 2 tables: A) correction values derived from the individual's IS, B) calculated insulin dose for carb content (personal C:I) for the most consumed carbs derived from the individual’s personal food diary. The intervention comprised 6 tutoring visits to a dietician, diabetes educator. The primary outcome was Hba1c post training.

Results: On the common tool were 39 pts. and 43 on the simple tool. Both groups showed significant statistical and clinical improvement; A1C declined -1.31% in the common tool and -1.59% in the simple method. The positive effects of CC using either method were unaffected by gender (-1.65% vs. -1.22% in males and females respectively P=0.43). We hypothesized that older age, language barrier or people with <12 years of education would benefit more from the simple tool compared to the common tool but no significant difference was found. Moreover, no significance was found among lower vs. higher education (>12 ys) (-1.32% vs. -1.64% respectively p=0.58). Newly diagnosed T1DM (≤1 year) in both groups had a significant decrease in HbA1c (-4.67%) compared to T1DM > 1 year (-.87%) (p<0.001). As expected, better compliance decreased the HbA1c. Those attending ≤ 2 meetings decreased by -.46% vs. -1.56% (p=0.051) in those attending 3-6 CC training sessions.

Discussion: CC was beneficial for all pts.; barriers such as age, gender, tutoring or spoken language didn’t hinder the benefits. Teaching CC close to diabetes diagnosis yielded better clinical results emphasizing the importance of early CC education. Our method provides an additional effective tool to better deliver patient -centered diabetes education.

Disclosure

S. Witkow: None. I.F. Liberty: Other Relationship; Self; AstraZeneca, Novo Nordisk Inc., Sanofi. I. Goloub: None. M. Kaminsky: None. O. Otto: None. Y. Abu Rabia: None. I. Harman Boehm: Advisory Panel; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Medtronic MiniMed, Inc., Merck Sharp & Dohme Corp., Merck Sharp & Dohme Corp., Novartis AG, Novo Nordisk Inc., Novo Nordisk Inc., Sanofi. Speaker's Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novartis AG, Sanofi.
347-LB: MEA Technology as an Easy Electrophysiological Approach for Noninvasive Recordings of Intact Murine and Human Islets
Authors: SCHöNECKER SVEN , OZA MAULIK , KRAUSHAAR UDO
Published: June 2019

Increase of blood glucose concentration leads to glucose-induced electrical activity of pancreatic beta-cells followed by insulin secretion. Electrical activity appears in glucose concentration-dependent oscillations easily recorded by microelectrode arrays (MEA). In comparison to other electrophysiological techniques MEAs can record non-invasively from intact islets and can be used for long term studies to investigate chronic effects of drugs.

Murine islets or islets isolated from human biopsies were used for recordings. Electrical activity was quantified as fraction of plateau Phase (FOPP) or number of single spike activity. Islets were placed via suction or cultivated on MEAs. The glucose concentration response curve recorded with murine islets plotted as FOPP revealed a half-maximal activity of 12 ± 2 mM which is in line with traditional methods like e.g., with intracellular electrodes. Glucose-induced activity of cultured islets remains stable over a month. Application of well-known substances (like e.g., diazoxide, tolbutamide) matched regular results. Human islets displayed typical glucose-induced activity (10 mM). Validation studies showed the existence of functional KATP channels and TTX reduced spike activity from 1047 ± 314 to 199 ± 90 spikes/5min after the application of 300 nM TTX. The washout led to an increased spike activity of 779 ± 301 spikes/minutes. The glucose concentration response curve revealed an EC50 value of 8 ± 3 mM glucose. The glucose responsiveness recorded with the MEA Technology is in line with other reports showing that the EC50 value of human beta-cells (∼ 6 mM) is lower than in mouse beta-cells.

MEA Technology allows medium throughput recordings from up to 40 intact islets simultaneously. While previous electrophysiological attempts failed MEAs offer large scale research in both academics and industry. The principle of function is not limited to rodent but is also applicable to human or stem cell derived islets of Langerhans.

Disclosure

S. Schönecker: None. M. Oza: Employee; Self; Multichannel Systems, Gmbh. U. Kraushaar: None.
36-LB: Mechanism of Neurotrophin-Mediated Neuroprotection in Diabetic and Hypoxic Conditions
Authors: LE YUN , QIU FANGFANG , ZHU MEILI
Published: June 2019

To develop neuroprotective strategy for diabetic retinopathy (DR) and age-related macular degeneration (AMD), we studied the mechanism of trophic factor production/secretion by Müller cell (MC) and of MC viability in vivo and in vitro models under diabetic and hypoxic conditions. MC secreted a high level of brain-derived neurotrophic factor (BDNF) in high glucose media, which was elevated significantly by adding recombinant vascular endothelial growth factor (rVEGF) in a dose-dependent manner. This result was supported by VEGF upregulated BDNF synthesis in MCs and by reduced retinal BDNF in diabetic/hypoxic MC-specific VEGF receptor-2 (VEGFR2) knockout (KO) mice, which appeared to have an accelerated loss of retinal MCs and neurons. In addition, rBDNF and rVEGF promoted MC viability in a synergistic fashion. Targeting the main retinal BDNF receptor, tropomyosin receptor kinase B (TRK-B), with siRNA caused a significant reduction of activated ERK and MC viability. Parallel analyses for glial cell line-derived neurotrophic factor (GDNF) demonstrated a similar effect in GDNF production, MC protection, and survival pathway activation.

In conclusion, neurotrophins are capable of elevating MC viability under diabetic/hypoxic condition, which provide a critical support for MC to produce themselves and other trophic factors for neuroprotection. As a substantial portion of patients treated with anti-VEGF drugs for 5 years appeared to have very thin retinas (presumably severe retinal cell/neuron loss), which bears striking resemblance to that in our diabetic/hypoxic MC-specific VEGFR2 KO mice, it is likely that blocking VEGF signaling in MC may cause unwanted retinal neuronal degeneration in AMD patients subjected to long-term anti-VEGF treatment due to blocking VEGF signaling-mediated reduction of neurotrophin and other trophic factor production. Therefore, supporting MC viability with neurotrophins may be a feasible strategy for neuroprotection during anti-VEGF treatment.

Disclosure

Y. Le: None. F. Qiu: None. M. Zhu: None.
36-OR: Energy Stress Restores Muscle Insulin Action in High-Fat (HF)-Fed SIRT3 KO Mice
Authors: LANTIER LOUISE , HUGHEY CURTIS C. , WASSERMAN DAVID
Published: June 2019

SIRT3 is a mitochondrial deacetylase that is necessary for insulin-stimulated muscle glucose uptake (MGU) in the setting of overnutrition, and its action is redox state-dependent (NAD/NADH). Energy stress induced by AICAR administration increases muscle insulin action and glucose uptake while enhancing the control of redox state. We hypothesized that acute energy stress would exacerbate the impairment in insulin-stimulated MGU in high fat-fed (HF) SIRT3 KO mice. To test this hypothesis, HF SIRT3 KO and WT littermates underwent 4h of either AICAR (1mg/kg/min) to induce an energetic stress or saline infusion followed by hyperinsulinemic (4mU/kg/min) euglycemic clamps. Experiments were conducted one week post jugular vein and carotid artery catheterization. Insulin clamps were combined with [3-3H] glucose to measure glucose fluxes and 2[14C]deoxyglucose to assess an index of MGU. AICAR significantly improved insulin sensitivity of liver, but not muscle of HF WT mice. Saline-SIRT3 KO mice were more insulin resistant than saline-WT mice, as glucose infusion rate (GIR) and MGU were reduced by ~50%. AICAR completely abolished the added insulin resistance in SIRT3 KO mice as GIR was similar to AICAR-WT. Consistent with this, AICAR increased muscle insulin-stimulated MGU in the SIRT3 KO mice to levels observed in WT mice. Results show that energy stress induced by AICAR infusion was sufficient to circumvent the defect in insulin-stimulated glucose uptake induced by SIRT3 KO, possibly by rescuing redox handling in skeletal muscle.

Disclosure

L. Lantier: None. C.C. Hughey: None. D. Wasserman: None.

Funding

National Institutes of Health (DK54902)
366-OR: TCF19 Promotes Functional Beta-Cell Mass and Proliferative Capacity by Regulating DNA Damage Repair Pathways
Authors: YANG GRACE H. , HAN JEE YOUNG , LODH SUKANYA , BLUMER JOSEPH T. , FONTAINE DANIELLE , DAVIS DAWN B.
Published: June 2019

Transcription factor 19, TCF19, is a novel gene associated with type 1 and type 2 diabetes. We have previously shown that Tcf19 is involved in the regulation of proliferation and apoptosis in the INS1 β-cell line. To determine the role of Tcf19 in diabetes pathogenesis, we generated germline whole body Tcf19 knockout mice (wbTcf19KO). Lean wbTcf19KO mice have slightly increased fasting glucose and decreased in vivo glucose-stimulated insulin secretion. We focused on the pancreatic islet in further analysis of this model due to the high expression of Tcf19 in the mouse islet and our preliminary findings in a β-cell line. RNAseq from wbTcf19KO mouse islets identified significantly decreased expression of genes involved in maintaining β-cell identity, vesicle docking, and Ca2+ sensing (Nkx6.1, Nkx2.2, Pdx1, Sort1, Syt7). Additionally, the proliferative marker, Ki67, was downregulated by 3-fold. Similarly, with immunohistochemistry of pancreatic sections, there was a 20% decrease in Ki67+ β-cells in wbTcf19KO mice. Despite no difference in overall β-cell mass compared to control mice, wbTcf19KO mice have an altered islet size distribution with an increased quantity of small islets. In addition, wbTcf19KO mice fail to increase proliferative genes in the islet, such as cyclinD2 and Ki67, in response to a short term high fat diet (HFD). Islet RNA seq analysis also showed an upregulation of genes involved in the DNA damage pathway, inflammation, and pro apoptotic genes (Ddx60, Gadd45a, Dtx3l, Chop, Bak, Ifit1, Cxcl10). Baseline levels of DNA damage in the wbTcf19KO islets are increased, as measured by γH2AX on western blot. wbTcf19KO mouse islets also have increased DNA damage after in vivo challenge with extended HFD feeding or ex vivo after cytokine exposure. Taken together, we conclude that Tcf19 plays an important role in regulating β-cell DNA damage repair pathways to prevent apoptosis and allow proliferation.

Disclosure

G.H. Yang: None. J. Han: None. S. Lodh: None. J.T. Blumer: None. D. Fontaine: None. D.B. Davis: None.
370-P: Changes in Glutamate Dynamics in the Anterior Cingulate Cortex with Recurrent Hypoglycemia in Type 1 Diabetes
Authors: PARK YOUNG WOO , DEELCHAND DINESH , KUMAR ANJALI , MOHEET AMIR , ZHANG YUAN , EBERLY LYNN E. , SEAQUIST ELIZABETH R. , OZ GULIN
Published: June 2019

The mechanisms of how recurrent hypoglycemia (HG) leads to impaired awareness of HG (IAH) remain elusive. Cortical glutamate (Glu) dynamics may be involved, as Glu levels were shown to decrease during HG in healthy controls and in patients with type 1 diabetes (T1D) and normal awareness of HG (T1D-NAH), but not in patients with IAH. While these data supported an association between blunted Glu response to HG and IAH, whether recurrent HG causes a blunting of the Glu response to HG remains unclear. We measured the neurochemical response to HG before and after induction of IAH in T1D-NAH patients undergoing four 2-hour HG clamps over 2 days. 1H-magnetic resonance spectroscopy at 7 tesla was used to measure Glu levels in the anterior cingulate cortex (ACC, 24x12x30 mm3) during the first (C1) and fourth clamps (C4), before and after induction of IAH, respectively. We focused on the ACC as differences in PET-measured glucose kinetics in ACC were associated with IAH. Epinephrine and symptom responses to HG during C1 and C4 confirmed induction of IAH. Glu levels significantly decreased in response to HG during C1, but not during C4. Glucose+Taurine (reported as sum due to cross-correlation) dropped by 40% with HG in C1, whereas it dropped by 32% in C4. We show that recurrent HG blunts the cortical Glu response to HG, which may be due to higher glucose or alternative fuel availability, eliminating the need to oxidize Glu.

Disclosure

Y. Park: None. D. Deelchand: None. A. Kumar: None. A. Moheet: None. Y. Zhang: None. L.E. Eberly: None. E.R. Seaquist: Advisory Panel; Self; Eli Lilly and Company, Zucara Therapeutics Inc. Consultant; Self; 360 Consulting, MannKind Corporation. Research Support; Self; Eli Lilly and Company, JDRF, National Institutes of Health. Other Relationship; Self; American Diabetes Association, Sanofi, WebMD. G. Oz: None.

Funding

National Institutes of Health (R01NS035192, P41EB015894, P30NS076408)
377-P: Prospective Risk Assessment of Hypoglycemia in Type 1 Diabetes Mellitus Outpatient Pediatric Population
Authors: COSSEN KRISTINA , FIGUEROA JANET , MUIR ANDREW B.
Published: June 2019

Objectives: The goal was to implement a risk profile that would prospectively identify youth with T1D at risk of severe hypoglycemia (SH) over the course of 1 year. We hypothesized that subjects with specific risk factors such as prior SH, a high frequency of nocturnal hypoglycemia (NH), and impaired hypoglycemia awareness would have a high rate of SH within the following year. If confirmed, an accurate assessment can lead to efficient application of interventions to reduce future risk of SH.

Methods: 404 subjects were followed for 14 months for SH, defined as a seizure, coma or loss of consciousness in the setting of presumed hypoglycemia (ISPAD guidelines). Subjects completed a survey that queried about SH, NH, and hypoglycemia unawareness. Comparisons were made using Chi-squared or Fisher’s exact tests for categorical variables and Wilcoxon Rank-Sum tests for continuous variables.

Results: Of the 404 enrolled, 18 subjects had SH in 14 months (4.46%). In the univariate analysis, those who had SH had indicated SH on the enrollment questionnaire (p-value 0.0015) and hypoglycemia unawareness as always or often (p-value 0.0259). Subjects with SH were more likely to wear CGMs (p-value 0.0369). Subject characteristics, T1D management, insurance, and NH were not statistically significant. In addition, we evaluated the 13 subjects who indicated on their initial questionnaire SH in the prior three months. In the univariate analysis, those subjects had more NH defined as ≥2 nights in a 3 month period (P=0.006) and less hypoglycemia awareness (P=0.030). With regards to insulin management, they had a lower insulin sensitivity factor (P=0.012) and higher proportion of basal insulin (P=0.003).

Conclusions: In a diverse cohort of T1D, this study shows the ability to identify pediatric subjects at risk for SH with hypoglycemia unawareness and prior SH. As SH is a rare event, as this study is expanded, there is the opportunity for a scored risk questionnaire to capture T1D youth at risk for SH.

Disclosure

K. Cossen: None. J. Figueroa: None. A.B. Muir: None.
383-P: The Potential Role of Il-6 in Defective Glucose Sensing following Recurrent Hypoglycaemia
Authors: MCNEILLY ALISON D. , GALLAGHER JENNIFER , MCCRIMMON RORY J.
Published: June 2019

Hypoglycaemia is common in insulin-treated therapy in the management of type 1 and long duration type 2 diabetes. Hypoglycemia evokes a significant stress response stimulating the release of several inflammatory mediators including interleukin 6 (IL-6). Importantly, glial cells also release IL-6 in response to glucose deprivation. We have previously demonstrated a role for IL-6 in the induction of defective neuronal glucose sensing in vitro. Here we investigate the potential role of IL-6 in the development of defective counter-regulatory response (CRR) to hypoglycaemia in vivo.

IL-6Ra-/- mice were generated by crossing IL-6RaFlx/flx with Nestin-Cre+/-animals. Male IL-6Ra-/- and Cre+/- animals (Control) 18 weeks old, n=10/12 per group) were fed standard laboratory chow for 20 weeks. Hormonal response to hypoglycaemia was assessed in vivo by hyperinsulinaemic-hypoglycaemic clamps. Plasma epinephrine and glucagon were measured by ELISA in response to either acute (single hypo; AH) or recurrent (3 episodes per week for 4 weeks; RH) hypoglycaemia. Data are expressed as mean±SEM.

The epinephrine response to hypoglycaemia was significantly elevated (>3 fold higher) in male IL-6Ra-/- animals following AH when compared to their control counterparts (0.38±0.09 vs. 1.31±0.28 delta; p<0.05). Plasma glucagon levels were comparable between genotypes (p=ns). In contrast, there was a significant suppression of the CRR to hypoglycaemia in both Control and IL-6Ra-/- animals following RH. Indeed, both IL-6Ra-/- and Control animals had suppressed epinephrine (50% and 68% reduction) and glucagon (65% and 44% reduction) responses to following RH when compared to their non-RH counterparts.

These findings highlight an important role for central IL-6 signaling in response to acute hypoglycemia, however, additional mechanisms appear to contribute to the development of defective CRR following RH.

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
393-P: Association of Hypoglycemia Prevention Measures with Quality of Life: A Retrospective Analysis of Electronically-Reported Patient Data
Authors: ALI KHAWLA F. , LAWRENCE LIMA , BUEHLER LAUREN A. , GAMBINO RONALD R. , HAMATY MARWAN
Published: June 2019

Introduction: Hypoglycemia in patients with diabetes presents deleterious effects on quality of life (QoL). We aimed to utilize electronically patient-reported data to identify the correlation of patients’ behaviors, intended to prevent and manage hypoglycemia, with QoL scores.

Methods: In a retrospective single center cohort study, we identified adults with type 1 or 2 DM seen between January 2017 and March 2018 who completed two questionnaires. First, the ADA Low Blood Sugar Questionnaire which assessed the incidence of self-reported hypoglycemia and behaviors intended to prevent and manage hypoglycemia. Second, the Patient-Reported Outcomes Measurement Information System (PROMIS) Survey which evaluated self-reported physical and mental QoL scores. Associations between hypoglycemic behaviors and QoL scores were determined using Spearman correlations.

Results: We identified 538 subjects, with a mean (±SD) age of 53.1±15.3 years, a mean household income of $51,400 ±17,9384, 55% were female, and 66% were on insulin therapy. Patients with fewer severe hypoglycemic episodes had significantly better physical and mental QoL scores (p<0.001, for both). Subjects who carried glucagon emergency kits had significantly higher physical QoL scores (p=0.001), while having a relative able to administer glucagon was associated with significantly higher physical and mental QoL scores (p=0.001 and p=0.003). Carrying snacks or glucose tablets and monitoring glucose before driving were associated with higher physical QoL scores (p<0.001 and p=0.010).

Conclusion: Significant positive correlations were found between patients’ practices intended to reduce and treat hypoglycemia and QoL scores. People with diabetes and low QoL scores require special treatment considerations.

Disclosure

K.F. Ali: None. L. Lawrence: None. L.A. Buehler: None. R.R. Gambino: None. M. Hamaty: Consultant; Self; Applied Clinical Intelligence, LLC.

Funding

Merck & Co., Inc.
403-P: Cerebral Blood Flow Responses to Hypoglycemia in Healthy Humans Treated with Induction Protocol to Produce Impaired Awareness of Hypoglycemia
Authors: CANNA ANTONIETTA , GROHN HEIDI , MASCALI DANIELE , FILIP PAVEL , MOHEET AMIR , KUMAR ANJALI , LI XIUFENG , OLAWSKY EVAN A. , EBERLY LYNN E. , ESPOSITO FABRIZIO , SEAQUIST ELIZABETH R. , MANGIA SILVIA
Published: June 2019

In this study, we sought to determine by 3T MRI the cerebral blood flow (CBF) responses to hypoglycemia (HG) in nondiabetic controls exposed to either two euglycemic or two hypoglycemic clamps on the day before the MRI (EU- or HYPO-preconditioning, respectively). Under the belief that HYPO-preconditioning induces hypoglycemia-associated autonomic failure (HAAF) with blunting of the counter-regulatory hormone and symptom responses to HG (Arbelaez et al, 2008), we hypothesized that CBF responses after HYPO-preconditioning would resemble those reported in T1D subjects with impaired awareness of hypoglycemia (IAH) (Weigers et al, 2017). CBF was measured by arterial spin labeling during a 2-step hyperinsulinemic clamp [step 1 = 95 mg/dL normoglycemia (NG), step 2 = 50 mg/dL (HG)]. Symptom and counter-regulatory hormone were also measured. Full CBF datasets were obtained from 10 participants who underwent EU-preconditioning (7F/3M, age 37 ± 14 years, BMI 27.2 ± 3.7 kg/m2) and 9 who underwent HYPO-preconditioning (5F/4M, age 40 ± 14 years, BMI 26.2 ± 2.6 kg/m2). In contrast with our assumption, the HYPO-preconditioning did not induce blunting of symptom or counter-regulatory hormone responses to HG other than for glucagon (33 ± 19 and 14 ± 21 pg/mL for EU- and HYPO-preconditioning, respectively, p=0.04 uncorr). CBF responses did not differ between the two pre-conditionings, and resembled those reported in the literature in naïve nondiabetic controls (Weigers et al, 2017). In particular, the cortical grey matter CBF did not change during HG vs. NG for either the EU- or HYPO-preconditioning settings (1 ± 10% and 2 ± 10%, respectively), while thalamic CBF increased in both settings (21 ± 20%, p=0.012 corr, and 27 ± 30%, p=0.06 corr, respectively). We conclude that the preconditioning protocols should be used with caution in nondiabetic controls for investigating IAH, as the mechanisms of HAAF in T1D patients may be specific to their disease condition.

Disclosure

A. Canna: None. H. Grohn: None. D. Mascali: None. P. Filip: None. A. Moheet: None. A. Kumar: None. X. Li: None. E.A. Olawsky: None. L.E. Eberly: None. F. Esposito: None. E.R. Seaquist: Advisory Panel; Self; Eli Lilly and Company, Zucara Therapeutics Inc. Consultant; Self; 360 Consulting, MannKind Corporation. Research Support; Self; Eli Lilly and Company, JDRF, National Institutes of Health. Other Relationship; Self; American Diabetes Association, Sanofi, WebMD. S. Mangia: None.

Funding

National Institutes of Health