bluuebunny/crossref_metadata_2025 huggingface dataset:
Epsin Deficiency Promotes Lymphangiogenesis through Regulation of VEGFR3 Degradation in Diabetes
Authors: CHEN HONG
Published: June 2018

Lymphangiogenesis occurs in adult tissues of chronic complex diseases, including diabetes. Whether lymphangiogenesis is altered owing to diabetic complication remains unknown. VEGF-C/VEGFR-3 signaling axis fuels the growth of lymphatic vessels. How VEGF-C/VEGFR3 signaling is regulated under pathological conditions, such as diabetes, however, is poorly understood. Here, we report that mice with inducible lymphatic endothelial cell-specific deficiency of epsins 1 and 2 (LEC-iDKO) display enhanced lymphangiogenesis compared to wild type (WT) in diabetic condition. A profound increase in VEGF-C-induced lymphatic vessel growth is exhibited in corneas and subcutaneous Matrigel implanted in diabetic LEC-iDKO mice compared to diabetic WT mice. Conversely, lymphatic endothelial cells isolated from diabetic WT mice show marked impairment in proliferation, migration, and tube formation in response to VEGF-C relative to those from diabetic LEC-iDKO in vitro. Mechanistically, reactive oxygen species (ROS) generated from hyperglycemia induces c-Src-dependent VEGFR3 phosphorylation independent of VEGF-C, which parallels c-Src-dependent epsin upregulation through the transcription factor AP-1. Heightened epsin expression induced by ROS facilitates epsin binding to VEGFR3 within Golgi compartment, promoting degradation of newly synthesized VEGFR3, and progressively reducing availability of VEGFR3 at the cell surface. Consequentially, lymphatic-specific epsin loss strengthens insufficient lymphangiogenesis and improves the resolution of tail edema in diabetic mice. Collectively, our data indicate that inhibiting epsin expression protects VEGFR3 against degradation and ameliorates diabetes-triggered downregulation of lymphangiogenesis, providing a plausible original therapeutic strategy to treat diabetic complication.

Disclosure

H. Chen: None.
Disruption of the Autophagy-Regulatory Becn1-Bcl2 Complex Impairs Insulin Storage and Secretion in Mice
Authors: YAMAMOTO SOH , WANG NAN , ZHANG WEIRAN , HE CONGCONG
Published: June 2018

Autophagy, a stress-induced lysosomal degradation pathway, has thought to exert similar metabolic effects in different organs. Yet the function and tissue-specific requirement of autophagy in metabolic regulation remain enigmatic. Here we establish a new model in which autophagy plays different roles in insulin-producing β cells vs. insulin-responsive cells, utilizing a point mutant (Becn1F121A) mouse model manifesting constitutively active autophagy under non-autophagy-inducing conditions. In response to high-fat diet challenge, we found unexpectedly that the autophagy-hyperactive mice show impaired glucose tolerance, but improved insulin sensitivity, compared to mice with normal levels of autophagy. We further demonstrated that autophagy hyperactivation increases insulin sensitivity in insulin-responsive cells, but decreases insulin load and secretion by sequestrating and degrading secretory vesicles containing insulin granules in β cells, a process we characterized as vesicophagy. The reduction in insulin secretion was not due to islet degeneration; instead, the β cell mass was expanded in the mutant mice, suggesting higher β cell regeneration. The reduction in insulin storage, insulin secretion, and glucose tolerance in autophagy-hyperactive mice can be reversed by transient treatment of an autophagy-blocking ULK1 kinase inhibitor. Thus, we conclude that β cells and insulin-responsive tissues require different levels of autophagy for their optimal functions. Importantly, our findings suggest that acute or intermittent, rather than chronic, activation of autophagy should be considered in therapeutic development against type 2 diabetes, to improve insulin sensitivity without negatively affecting insulin secretion.

Disclosure

S. Yamamoto: None. N. Wang: None. W. Zhang: None. C. He: None.
Regulation of Hepatic Glucose Production by Transforming Growth Factor Beta 1 via Protein Kinase A
Authors: PAN QUAN , CHEN YUNMEI , YAN HUI , YANG WANBAO , SHEN ZHENG , DAHANAYAKA SUDATH A. , GUO SHAODONG
Published: June 2018

Hepatic glucose production (HGP) is crucial for blood glucose homeostasis, while an impaired regulation of HGP contributes to hyperglycemia in patients with type 2 diabetes mellitus. Hepatokines are proteins secreted by hepatocytes, and some of them can directly affect glucose metabolism. Here we examined the role of transforming growth factor beta 1 (TGF-β1) in regulating glucose homeostasis. We generated the liver-specific TGF-beta1 knockout mice and found that hepatic TGF-β1 deficient mice exhibited a lower blood glucose levels. Hepatic TGF-β1 deficiency increased insulin sensitivity and protected mice from diet-induced obesity and hyperglycemia. In vitro studies using mouse primary hepatocytes, TGF-β1 augmented glycogenolysis and gluconeogenesis, activated protein kinase A (PKA) signaling, promoted the stability of the O-class of the forkhead transcription factor 1 (Foxo1), and increased the level of key gluconeogenic genes, glucose-6-phosphatase (G6Pase) and phosphorenolpyruvate carboxykinase (PEPCK). These findings underscore an important role of hepatic TGF-β1 in contribution to blood glucose homeostasis, and hepatic TGF-β1 may serve as an important hepatokine and therapeutic target for glycemic control in insulin resistance and type 2 diabetes mellitus.

Disclosure

Q. Pan: None. Y. Chen: None. H. Yan: None. W. Yang: None. Z. Shen: None. S.A. Dahanayaka: None. S. Guo: None.
Neudesin, a Novel Regulator of Energy Metabolism in Obesity and Type 2 Diabetes Mellitus—The Effect of Acute Fasting and Endoscopic Duodenal-Jejunal Bypass Liner Implantation
Authors: KRATOCHVILOVA HELENA , LACINOVÁ ZDENA , KLOUCKOVA JANA , KAVÁLKOVÁ PETRA , CINKAJZLOVA ANNA , TRACHTA PAVEL , KRIZOVA JARMILA , BENES MAREK , VLASAKOVA ZUZANA , PELIKANOVA TEREZIE , MRAZ MILOS , HALUZIK MARTIN
Published: June 2018

Neudesin has recently been identified as a negative regulator of energy expenditure in experimental animals; however, its role in humans remains unexplored. The aim of our study was to assess the effects of obesity and type 2 diabetes mellitus along with selected interventions including acute fasting and endoscopic duodenal-jejunal by-pass liner implantation (DJBL) on its serum levels and adipose tissue mRNA expression. Fifteen obese T2DM subjects undergoing DJBL implantation, 15 subjects with functional hypoglycemia subjected to 72-hour fasting (Fast) and 12 healthy controls (C) were included in the study. Samples were taken at baseline and 6 and 10 months after DJBL and after 78 hours of fasting and 2 hours after realimentation, respectively. Serum neudesin was measured using ELISA kit (Neudesin Human ELISA, Biovendor, CR). qRT PCR was used to detect mRNA expression of neudesin in white adipose tissue (WAT). Baseline serum neudesin levels were comparable between all groups (1.77 ± 0.86 vs. 1.74 ± 0.54 vs. 1.88 ± 0.70 ng/ml, n.s. for DJBL vs. Fast vs. C). Along with reduction in body weight (BMI 42.8 ± 6.53 vs. 36.6 ± 4.91 kg/m2, p=0.038) and improvement of HbA1c (73.5 ± 17.2 vs. 50.0 ± 12.6 mmol/mol, p=0.001) DJBL increased serum neudesin at 6 and 10 months after procedure (1.77 ± 0.86 vs. 2.28 ± 1.27 vs. 2.13 ± 1.02 ng/ml, p=0.001 for baseline vs. 6 vs. 10 months), while having no effect on neudesin mRNA expression in WAT. In contrast, acute fasting decreased serum neudesin during the whole period (1.74 ± 0.54 vs. 1.46 ± 0.48 ng/ml, p=0.001 for baseline vs. 72 hours) with no impact of subsequent realimentation (1.37 ± 0.44 ng/ml, n.s. 2 h postprandially).To conclude, serum neudesin levels are regulated differently during acute fasting and chronic weight reduction induced by DJBL. Further studies are needed to assess its potential in the treatment of obesity and T2DM.

Disclosure

H. Kratochvilova: None. Z. Lacinová: None. J. Klouckova: None. P. Kaválková: None. A. Cinkajzlova: None. P. Trachta: None. J. Krizova: None. M. Benes: None. Z. Vlasakova: None. T. Pelikanova: None. M. Mraz: None. M. Haluzik: None.
Comparative Effects of Medical vs. Surgical Weight Loss on Body Composition in a Randomized Trial
Authors: VARMA SANSKRITI , BROWN TODD , CLARK JEANNE , MARUTHUR NISA , SCHWEITZER MICHAEL , MAGNUSON THOMAS , LEE CLARE
Published: June 2018

Bariatric surgery leads to more rapid and greater weight loss (WL) compared to medical weight loss (MWL), but differences in body composition changes for these methods of WL remain unclear. Due to the known health risks associated with central adiposity, we sought to understand if changes in regional distribution of fat mass (FM) and lean mass (LM) differ by surgical vs. medical WL. This 1:1:1 randomized trial among 15 persons with type 2 diabetes and BMI 30-39.9 kg/m2 compared changes in body composition (measured by dual energy x-ray absorptiometry) at the time of 10% WL (or nine months after intervention) for patients receiving MWL, adjustable gastric banding (AGB), or Roux-en-Y gastric bypass (RYGB). We used non-parametric tests to evaluate differences across all arms and to compare AGB to RYGB. We present results for the 12 participants who received the study intervention and completed follow-up. All participants were women, and 75% were African American. Time to 10% weight loss was shorter for AGB and RYGB. Total FM losses were similar across arms. While differences across arms were not statistically significant, the AGB arm tended to have greater total LM and peripheral FM losses.

In conclusion, at similar overall WL, AGB may lead to preferential loss of peripheral FM and total LM. The change in total FM and truncal FM were similar across all three groups. Larger studies are needed to confirm these findings.

 MWLAGBRYGBPALLPAGB vs. RYGBN444Age (Years, Mean)4654.351.5Mean BMI, Kg/m2Baseline37.135.535Final353231.6Weight, KgBaseline104.796.394.4Final98.286.985.4% Change-6.1-9.8-10.00.0381.0Time to 10% Weight Loss, months7.472.772.510.0380.77Body Composition OutcomesTotal Fat Mass, KgBaseline50.043.044.5Final45.537.738.9% Change-8.5-12.0-12.90.671.0Truncal Fat Mass, KgBaseline24.424.724.2Final21.722.020.4% Change-11.0-10.9-16.30.670. 77Peripheral Fat Mass, KgBaseline24.217.019.2Final22.614.417.3% Change-5.0-15.0-8.70.670.56Lean Mass, KgBaseline53.251.546.9Final50.444.943.3% Change-5.2-12.4-7.30.070.15Abbreviations: MWL: medical weight loss, AGB: adjustable gastric band, RYGB: Roux-en-Y gastric bypass, BMI: body mass indexPALL for comparison across groups using Kruskal-Wallis testPAGB vs RYGB represents comparison of AGB to RYGB group using Wilcoxon-Mann-Whitney test

Disclosure

S. Varma: None. T. Brown: Advisory Panel; Self; Merck & Co., Inc.. J. Clark: None. N. Maruthur: None. M. Schweitzer: Consultant; Self; Ethicon US, LLC.. T. Magnuson: None. C. Lee: None.
Therapeutic Potential of EP3 Receptor Antagonists for Treatment of Noninsulin Dependent Diabetes Mellitus across Multiple Preclinical Models
Authors: RANKIN MATTHEW M. , GUO LILI , BAKAJ IVONA , HO GEORGE , RADY BRIAN , ZHAO SHUYUAN , STAHLE PAUL L. , GHOSH AVIJIT , SHI YIFAN , PATEL SHEFALI , TRYPUTSEN VOLHA , LUBOMIRSKI MARIUSZ , ZHANG XUQING , ZHU BIN , WINTERS MICHAEL P. , MACIELAG MARK J. , NORQUAY LISA D.
Published: June 2018

The EP3 receptor (EP3r) is a member of the EP receptor subfamily, which facilitate a broad range of physiological and pathological prostaglandin E2 (PGE2) actions. Multiple reports have demonstrated that infusion of PGE2 blunts glucose-stimulated insulin secretion (GSIS) in healthy subjects and that inhibition of PGE2 production in noninsulin dependent diabetes mellitus (NIDDM) patients can partially restore impaired GSIS. The suppression of GSIS by PGE2 has been attributed to EP3r, resulting in the suggestion that EP3r antagonism may be an attractive strategy for treatment of NIDDM. We sought to investigate the therapeutic potential of EP3r antagonists in preclinical models. EP3r-mediated suppression of GSIS was validated in vivo using a dose-range (3-30 µg/kg/minutes) of the EP3r-specific agonist sulprostone in conscious rat ivGTTs. Using this model, we defined the EP3r antagonist plasma exposure required to oppose maximal EP3r-mediated GSIS suppression. Efficacy of an EP3r-specific antagonist was then evaluated in the GK, ZDF, and DIO/streptozotocin diabetic rat models. Despite achieving plasma concentrations at least 2-fold higher than the efficacious exposure predicted by the ivGTT model, an EP3r antagonist did not impact GSIS nor glucose homeostasis in these models. We further interrogated the ability of EP3r to suppress GSIS in conscious non-human primates (NHPs) using infusions of both sulprostone and an EP3r-specific antagonist during ivGTT. In NHPs sulprostone resulted in a significant reduction in both the fasting insulin and acute insulin response compared to vehicle. Surprisingly, EP3r agonism also significantly suppressed fasting plasma glucagon. Given the combined effect on islet hormone secretion in NHPs, and the lack of EP3r antagonist efficacy across multiple diabetic rodent models, these results call into question the therapeutic potential of EP3r antagonists for NIDDM patients.

Disclosure

M.M. Rankin: Employee; Self; Janssen Research & Development. L. Guo: None. I. Bakaj: None. G. Ho: None. B. Rady: Employee; Self; Janssen Research & Development. S. Zhao: Employee; Self; Janssen Research & Development. P.L. Stahle: Employee; Self; Janssen Research & Development. A. Ghosh: None. Y. Shi: Employee; Self; Janssen Research & Development. Employee; Spouse/Partner; Bristol-Myers Squibb Company. S. Patel: None. V. Tryputsen: None. M. Lubomirski: None. X. Zhang: None. B. Zhu: Employee; Self; Janssen Research & Development. M.P. Winters: None. M.J. Macielag: Employee; Self; Janssen Research & Development. L.D. Norquay: Employee; Self; Janssen Research & Development.
Impacts of a Two-Part Multidisciplinary Diabetes Education Program on Glycemic Control and Hospital Use
Authors: WHITLEY HEATHER P.Q. , STALLWORTH ANGELA , DESAI DEEPTHI , HANSON COURTNEY
Published: June 2018

Background: Emergency room and hospital use remain high among those with diabetes. Interventions need to be developed to reduce the utilization of this high-cost care while still improving diabetes management.

Purpose: To analyze changes in outcomes for patient with diabetes who attend a two-part multidisciplinary diabetes education program, which includes a 1-day DSME class and a ½ day “Speed Dating” session in terms of ER and hospital use, A1C, and LDL-cholesterol from January 2016-2018.

Method: Adult patients with diabetes at a family medicine clinic are enrolled and attend an 8-hour DSME class followed by a 3-hour multidisciplinary clinic 2 weeks later during which patients rotate every 30 min through 5 centers hosted by a 1) family medicine physician, 2) clinical pharmacist (CDE), 3) nurse or dietician (CDE), 4) case manager, and 5) clinical psychologist to address and improve care. Data was systematically extracted from the electronic medical record (EMR) 6 months before, 6 and 12 months after attending the class to determine impact of the program. Paired t-tests determined significance between baseline and post-intervention measures.

Results: Over 24 months, 22 adults attended the program. At baseline patients had an average A1C of 10.2% and LDL of 115 mg/dL. Six months before attending the class they presented to the ER 0.68 times, were admitted to the hospital 0.5 times, and when admitted, had an average length of stay (LOS) of 5.3 days. After attending the program patients’ A1C declined to 9.1% at 6 months (p=0.28) and 8.7% at 12 months (p=0.022). Their LDL-C declined to 110 mg/dl (p = 0.71). Although ER use increased to 0.8, their hospital admission rate and LOS decreased to 0.36 and 3.3 days respectively per patient.

Implications: Incorporation of the DSME plus Speed Dating program improved care by lower A1C by 1.5%, hospital admission rate by 0.14, and LOS by 2 days over a 6-month window. Ultimately these improvements additionally lower healthcare costs.

Disclosure

H.P.Q. Whitley: None.A. Stallworth: None.D. Desai: None.C. Hanson: None.
Diabetes Educator Impact in Value-Based Care Models
Authors: KOSHINSKY JANICE L. , KRALL JODI , RUPPERT KRISTINE , KANTER JUSTIN , SOLANO FRANCIS X. , SIMINERIO LINDA M.
Published: June 2018

Background: Health systems are implementing value-based care models focused on quality. Organized care teams set the foundation for successful models with processes that address patient outreach and engagement. The purpose of this study was to evaluate the impact of “Glucose to Goal (G2G),” a diabetes educator (DE) driven, population-based intervention on glycemic improvement in reaching quality metrics for diabetes mellitus (DM) care.

Methods: A large primary care (PC) network established pod-style patient-centered medical homes (PCMHs) clustered by grouping multiple PC practices together based on patient panel size, hospital affiliation, and geographic proximity, and incorporating expanded care teams (DE, behavioral health, social worker, wellness guide, nurse care manager). Specific to DM, PCMHs adopted the G2G intervention whereby DEs used population health reports to proactively identify patients with HbA1c levels above target (>7%). G2G was assessed in 5 pods by comparing HbA1c values for only those patients with DM with pre/post results who participated over a three-month period (n=284) to those who did not (n=265).

Results: A total of 80% of patients receiving G2G improved their HbA1c levels with 46.8% reducing HbA1c by 1% and 24% reducing HbA1c by 2%. Comparatively, 31.3% of patients not receiving G2G improved their HbA1c with only 6.4% reducing HbA1c by 1% and only 1.5% reducing HbA1c by 2% or more. This translated into more than 1.5% difference in mean HbA1c change between groups, with patients receiving DE experiencing a mean reduction in HbA1c of 1.35% (8.61 to 7.26%) compared to increase of 0.35% (7.96 to 8.30%) for those not participating in DE (p<0.0001).

Conclusions: Study findings demonstrate the relevance of DE services in value-based PC models. As healthcare systems shift focus from volume to value, effective approaches to manage diabetes and improve patient outcomes take on new meaning.

Disclosure

J.L. Koshinsky: None.J. Krall: None.K. Ruppert: None.J. Kanter: None.F.X. Solano: None.L.M. Siminerio: None.
Mechanism by Which Dapagliflozin Induces Euglycemic Ketoacidosis in Rats
Authors: PERRY RACHEL J. , SONG JOONGYU D. , WANG YONGLIANG , SHULMAN GERALD I.
Published: June 2018

Sodium-glucose transport protein 2 inhibitors (SGLT2i) are the most recent class of antidiabetic agents; however concerns have been raised about their potential to induce euglycemic ketoacidosis by an unknown mechanism. Here we report that dapagliflozin increases rates of hepatic ketogenesis (35±4 vs. 136±8 μmol/[kg-min], p<0.0001) in normal Sprague-Dawley rats by increasing plasma catecholamine (epinephrine 0.5±0.1 vs. 7.3±0.5 nM, p<0.001, norepinephrine 2.5±0.5 vs. 19.8±5.2 nM, p<0.01) and corticosterone (115±15 vs. 233±28 ng/mL, p<0.01) concentrations secondary to volume depletion (weight change -1.9±0.4% vs. -7.1±0.4%), thereby increasing white adipose tissue lipolysis, hepatic acetyl-CoA content, hepatic glucose production and hepatic ketogenesis. Dapagliflozin-induced reductions in plasma insulin concentrations were shown to be necessary but not sufficient to induce these changes since the effects of dapagliflozin to increase hepatic ketogenesis were abrogated when extracellular volume depletion was prevented with saline infusion or free access to water. Furosemide treatment induced similar volume depletion and increases in plasma catecholamine and corticosterone concentrations without any associated changes in WAT lipolysis, hepatic glucose production or hepatic ketogenesis, likely due to its lack of an effect on plasma insulin levels. Furthermore the effects of dapagliflozin to promote increased rates of hepatic ketogenesis and hepatic glucose production were dissociated from changes in plasma glucagon concentrations, which increased (89.5±3.8 vs. 379.2±11.8 ng/mL, p<0.0001) through a central mechanism following ICV injection of dapagliflozin without any alterations in body weight or ketosis, and hepatic malonyl-CoA. Taken together these data identify SGLT2i-induced dehydration as a potential target to prevent SGLT2i-induced euglycemic ketoacidosis.

Disclosure

R.J. Perry: None.J.D. Song: None.Y. Wang: None. G.I. Shulman: Advisory Panel; Self; AstraZeneca, Janssen Research & Development, Merck & Co., Inc., Novo Nordisk Inc.. Research Support; Self; Gilead Sciences, Inc..
Neuronal FGF-21 Signaling–A Sensor of Dietary Protein Restriction
Authors: HILL CRISTAL M. , DEHNER MADELEINE V. , MCDOUGAL DAVID , BERTHOUD HANS-RUDOLF , MUENZBERG HEIKE , MORRISON CHRISTOPHER
Published: June 2018

The central nervous system is acknowledged as a major regulator of both energy and glucose homeostasis. Our data demonstrate that dietary protein restriction increases energy expenditure and improves glucose homeostasis, and that the metabolic hormone FGF-21 coordinates these adaptive responses. However, the tissue site mediating these FGF-21-dependent effects is unclear. In this study, mice with dysfunctional FGF-21 signaling in either the central nervous system (CNS) or adipose tissue were fed a control or low protein (LP) diet to assess changes in body weight and associated metabolic endpoints. We first deleted the required FGF co-receptor beta-Klotho (Klb) from neurons to test whether CNS FGF-21 signaling is required for increased energy expenditure or improved glucose homeostasis in mice consuming a low protein diet. Our data show that LP diet increased energy expenditure (p≤0.01) and reduced body weight (p≤0.001) in control littermates, but these effects were lost in mice bearing CNS-specific deletion of Klb (p=0.65). Protein restriction in the context of a high fat diet also improved glucose tolerance (P≤0.001) and insulin sensitivity (p≤0.001) in control littermates, but these effects were also lost in mice lacking Klb in the CNS. We next tested whether FGF-21 signaling within adipose tissue contributed to the metabolic effects of protein restriction. However, in this case LP diet reduced body weight (p=0.90) and increased food intake (p= 0.98) similarly in control littermates and mice bearing adipose-specific deletion of Klb. Collectively, these data highlight CNS FGF-21 signaling as the first known neuroendocrine mechanism to explain the coordinated metabolic changes induced by dietary protein restriction.

Disclosure

C.M. Hill: None. M.V. Dehner: None. D. McDougal: None. H. Berthoud: None. H. Muenzberg: None. C. Morrison: None.
New Prebiotics to Ameliorate High-Fat Diet-Induced Obesity and Diabetes via Modulation of Microbiome-Gut-Brain Axis
Authors: AHMADI SHOKOUH , NAGPAL RAVINDER K. , WANG SHAOHUA , YADAV HARIOM
Published: June 2018

Role of gut microbiome in obesity and diabetes became apparent from several independent studies, indicating that gut microbiome modulators like prebiotics may improve microbiome perturbations (dysbiosis) to ameliorate metabolic derangements. We isolated water soluble, non-digestible polysaccharides from 5 foods (acorn, quinoa, sunflower, pumpkin and sago seeds) and assessed their impact on amelioration of high fat diet (HFD)-induced obesity and diabetes in mice and human microbiome using fecal slurry culture model. During isolation, purification, biochemical and digestion resistance characterization, and fermentation pattern by human fecal microbiome, we selected acorn and sago derived prebiotics, on the basis of purity, protein contamination and yield. All prebiotics increased short chain fatty acid (SCFA) production along with enhanced microbial diversity. Feeding of acorn and sago derived prebiotics supplemented HFD (5%) for 8 weeks, significantly reduced diet induced glucose intolerance and insulin resistance, without affecting adiposity. Beneficial effects of acorn and sago derived prebiotics were superior than inulin-feeding. Feeding of both prebiotics and inulin increased diversity of gut microbiome and enhanced SCFA production into the mice gut. Metabolic function was positively correlated with increased food conversion ratio indicating enhanced whole body metabolic rate by prebiotic feeding. Gastrointestinal motility was enhanced without changing food intake, after probiotic intervention. Hypothalamic energy signaling in terms of increased pro-opiomelanocortin and decreased agouti-related peptide and neuropeptide Y expression, was modulated by prebiotics administration. These results indicate that newly isolated prebiotics ameliorate HFD-induced defects of glucose metabolism via modulating microbiome-gut-brain axis, and can be used to prevent/treat diet induced obesity and diabetes.

Disclosure

S. Ahmadi: None. R.K. Nagpal: None. S. Wang: None. H. Yadav: None.
Identifying Pathogenic Variants of Monogenic Diabetes Using Targeted Exome Sequencing
Authors: PARK SEUNG SHIN , JANG SE SONG , LEE YOUNG AH , CHO YOUNG MIN , JANG HAK CHUL , PARK KYONG SOO , KWAK SOO HEON
Published: June 2018

Background: Targeted exome sequencing is widely used for genetic diagnosis of rare disease and it is replacing Sanger sequencing. In this study we investigated pathogenic variants of monogenic diabetes genes in Korean early onset diabetes patients using targeted exome sequencing.

Method: The main eligible criteria for this study was: non-type 1 diabetes patients with age of onset < 30 years old and body mass index (BMI) < 30 kg/m2. Among the 2353 patients screened from the diabetes registry of Seoul National University Hospital Diabetes Clinic, a total of 93 participants were eligible. We analyzed 30 monogenic diabetes genes using targeted exome sequencing. Identified genetic variants were evaluated by ACMG-AMP guideline for their pathogenicity.

Result: Among the 93 index patients, a total of 83 rare (minor allele frequency < 0.5%), non-silent variants were found and evaluated for its pathogenicity according to the ACMG-AMP guideline. These variants were classified as likely benign (N=8), uncertain significance (N=59), likely pathogenic (N=13), and pathogenic (N=5). Three causative mutations were identified in HNF4A (p.R136W, p.M1I, p.R89Q), four mutations in five patients were identified in HNF1A (c.G-124C, p.Y166N, p.L26Q, p.R278Q), four mutations were found in GCK (p.G410S, p.N231S, p.L164F, p.H156fs) and one mutation was identified in HNF1B (p.L168P). Other causative mutations were identified in WFS1 (p.R629W), INS (c.C-60G), ABCC8 (p.R933Q) and FOXP3 (p.Q200R). Mitochondria 3243 A>G variant was identified in two patients. Patients with pathogenic variants had higher MODY probability score and lower BMI than those without causative gene variants (p=0.015, p=0.039, respectively).

Conclusions: In this study, a total of 19 (20.4%) participants were identified to have monogenic cause of diabetes among 93 early onset diabetes patients. Further research is required to validate the clinical utility of targeted exome sequencing in early onset diabetes patients.

Disclosure

S. Park: None. S. Jang: None. Y. Lee: None. Y. Cho: None. H. Jang: None. K. Park: None. S. Kwak: None.
Monogenic Diabetes in the Progress for Diabetes Genetics in Youth (ProDiGY) Collaboration
Authors: TODD JENNIFER , KLEINBERGER JEFFREY W. , SRINIVASAN SHYLAJA , TOLLEFSEN SHERIDA E. , LEVITSKY LYNNE L. , KATZ LORRAINE E.L. , TRYGGESTAD JEANIE B. , BACHA FIDA , IMPERATORE GIUSEPPINA , LAWRENCE JEAN M. , PIHOKER CATHERINE , DIVERS JASMIN , FLANNICK JASON , DABELEA DANA , FLOREZ JOSE C. , POLLIN TONI I.
Published: June 2018

Monogenic diabetes, including maturity-onset diabetes of the young (MODY), is frequently misdiagnosed as type 1 or type 2 diabetes. Correct diagnosis can result in a change in clinical treatment and impacts prediction of complications and familial risk. Clinical algorithms can select individuals for genetic testing; however, up to half of youth with MODY do not meet clinical criteria. Other barriers also limit access to genetic testing.

To assess the prevalence of MODY in youth with a clinical diagnosis of type 2 diabetes, we evaluated whole-exome sequence data from ProDiGY, a collaboration of the TODAY, SEARCH for Diabetes in Youth, and T2D-GENES studies. Focusing on 14 genes previously identified as causal for MODY (HNF4A, GCK, HNF1A, PDX1, HNF1B, NEUROD1, KLF11, CEL, PAX4, INS, BLK, KCNJ11, ABCC8, and APPL1) we considered patients to have MODY if they carried one or more variants classified as likely pathogenic (LP) or pathogenic (P) according to current guidelines. We found 77 of 3650 patients carried an LP/P variant in HNF4A (14 individuals), GCK (22), HNF1A (32), PDX1 (4), INS (3), and PAX4 (2). Compared to those with no LP/P variants, youth with MODY had a younger age at diagnosis (12.9 ± 0.3 vs. 13.6 ± 0.1, P=0.01) and lower fasting C-peptide levels (3.0 ± 0.2 vs. 4.5 ± 0.1, P=0.0001), although for both measures, the range of values overlapped between the two groups. Youth with MODY were less likely to have hypertension (6.9% vs. 18.2%, P=0.03) and less likely to be on insulin (32.0% vs. 51.1%, P=0.001). Parental history of diabetes was not significantly different. MODY was found in all race/ethnic groups.

Using a comprehensive set of MODY genes, we identified MODY in 2% of youth with clinically diagnosed type 2 diabetes; in 88% (n=68) the specific diagnosis would direct management. While these individuals differed significantly on several clinical characteristics, no criterion reliably separated the two groups. Further study is needed to find ideal criteria to select individuals for genetic testing.

Disclosure

J. Todd: None. J.W. Kleinberger: None. S. Srinivasan: None. S.E. Tollefsen: None. L.L. Levitsky: Consultant; Self; Eli Lilly and Company. L.E.L. Katz: None. J.B. Tryggestad: None. F. Bacha: Research Support; Self; AstraZeneca, JAEB Center For Health Research, National Institutes of Health, Pediatric Diabetes Consortium. G. Imperatore: None. J.M. Lawrence: None. C. Pihoker: None. J. Divers: None. J. Flannick: None. D. Dabelea: None. J.C. Florez: Consultant; Self; Intarcia Therapeutics, Inc.. Consultant; Spouse/Partner; Santen. T.I. Pollin: Research Support; Self; Regeneron Pharmaceuticals, Inc..
Digenic Mutations in the FGF-21 Signaling Pathway Found in an Adolescent with Extreme Insulin Resistance
Authors: STONE STEPHEN I. , ADESANYA ELIZABETH A. , WEGNER DANIEL J. , WAMBACH JENNIFER A. , COLE F. SESSIONS , ORNITZ DAVID M. , URANO FUMIHIKO
Published: June 2018

Fibroblast Growth fFactor-21 (FGF-21) is a secretory molecule that has multiple metabolic functions. However, its role in human insulin resistance remains unclear. Here we report a 12 year old female presenting to pediatric diabetes clinic with acanthosis nigricans, hirsutism, and acromegalic features. The subject was noted to have extremely elevated insulin (2446 uIU/mL) and elevated free testosterone (16 pg/mL). Due to her unique presentation, we hypothesized that she may have a genetic insulin resistance syndrome and whole exome sequencing was performed. 2 variants were identified in genes critical for FGF-21 signaling, Fibroblast Growth Factor Receptor 1 (FGFR1) and beta Klotho (KLB). These mutations were inherited in trans from each parent. FGFR1 and KLB are transmembrane co-factors that bind FGF-21, leading to activation of intracellular tyrosine kinases, and subsequent intracellular signaling. Fasting serum FGF-21 was elevated in the subject (391.3 pg/mL) compared to her father (104.3 pg/mL) and mother (225.2 pg/mL). A bicistronic expression plasmid was created recapitulating the above mutations found in this family. These plasmids were transiently transfected into L6 myoblasts, a cell line known to have low levels of FGF receptor expression. ERK phosphorylation (pERK), the major downstream signal of FGF-21, was measured after the cells were treated with FGF-21. pERK was strongly upregulated in the cells transfected with wild type FGFR1 and KLB (43,463 AU). However, mutations in either FGFR1 or KLB greatly attenuated pERK (13,601.5 and 15,526 AU respectively). The combination of mutations in both FGFR1 and KLB led to the lowest level of pERK (10,148.3 AU). We hypothesize that these digenic mutations in both FGFR1 and KLB are acting in a synergistic fashion leading to FGF-21 resistance. This helps explain the severe insulin resistance found in this subject and may represent a novel category of insulin resistance syndromes related to FGF-21.

Disclosure

S.I. Stone: Speaker's Bureau; Self; AbbVie Inc.. Research Support; Self; National Institutes of Health, Pediatric Endocrine Society. E.A. Adesanya: None. D.J. Wegner: None. J.A. Wambach: None. F. Cole: None. D.M. Ornitz: None. F. Urano: Research Support; Self; Eli Lilly and Company. Stock/Shareholder; Self; CytRx.
Predicting Insulin Secretion Profiles for Immunoisolating Devices with Transplanted Islets
Authors: BUCHWALD PETER , TOMEI ALICE A. , STABLER CHERIE L.
Published: June 2018

Avascular islets or stem cells transplanted under immunoisolating conditions offer considerable hope in overcoming the challenges of islet transplantation; however, because of diffusional limitations, implants face long-term viability and efficiency-of-response problems. To quantitatively characterize the glucose-stimulated insulin release of pancreatic islets, we conducted parallel dynamic perifusion experiments with free and hydrogel encapsulated islets. Perifused human islets secreted less insulin than murine islets per unit mass (IEQ) and had a less pronounced first-phase peak. The data was used to develop a computational model of insulin secretion. Our model couples hormone secretion and nutrient consumption kinetics with diffusive and convective transport, fits well the experimental data, and can be used to predict insulin release profiles for arbitrary geometries and glucose challenges. We found that larger diffusion distances (larger capsules) unavoidably dampen the first-phase insulin response, resulting in a sustained-release type insulin secretion that sluggishly responds to changes in glucose concentration. Hence, bioartificial pancreas devices can provide long-term and physiologically desirable solutions only if immunoisolation and biocompatibility considerations are considered together with optimized nutrient diffusion and insulin release characteristics.

Disclosure

P. Buchwald: None. A.A. Tomei: Consultant; Self; EyePharma. Research Support; Self; Semma Therapeutics, Inc.. Stock/Shareholder; Self; Converge Biotech Pvt. Ltd.. C.L. Stabler: None.
STAT5 Deficiency in Mature Adipocytes Results in Metabolically Healthy Adiposity, Reduced Growth Hormone Signaling in Adipose Tissue, and Decreased Energy Expenditure
Authors: RICHARD ALLISON J. , HANG HARDY , ALLERTON TIMOTHY D. , ELKS CARRIE M. , STEPHENS JACQUELINE M.
Published: June 2018

STAT5 proteins promote adipocyte development and regulate adipose tissue function in vitro and in vivo. To further elucidate the role of STAT5 proteins in adipocytes, we used adiponectin-Cre and floxed STAT5 A/B mice to generate mice that lack both STAT5A and STAT5B in mature fat cells (STAT5AKO). Studies on several cohorts of both sexes of mice have revealed that STAT5AKO mice have increased adiposity. Notably, the adiposity phenotype disappears upon high fat feeding when growth hormone (GH) levels and GH signaling are diminished. Another striking observation is that obese STAT5AKO female mice are highly resistant to weight loss induced by low fat feeding when compared to floxed control mice that exhibit significantly enhanced weight loss and reduced adiposity. The adiposity of STAT5AKO mice is not a result of alterations in food intake or lean body mass. Furthermore, the increased adiposity in STAT5AKO mice is uncoupled from insulin resistance and metabolic dysfunction. It is well known that chronic elevation of GH is associated with insulin resistance. However, in most mammals a disruption of the IGF-1 axis accompanies altered GH signaling. Notably, STAT5AKO mice do not have alterations in circulating IGF-1 levels. In addition, the adiposity phenotype of STAT5AKO mice does not appear to be associated with alterations in basal or stimulated lipolysis. However, STAT5AKO female mice have a significant reduction in energy expenditure and fat oxidation.

In summary, our extensive phenotypic characterization of STAT5AKO mice has shifted our understanding of the metabolic actions of growth hormone and functions of STAT5 proteins.

Disclosure

A.J. Richard: None. H. Hang: None. T.D. Allerton: None. C.M. Elks: None. J.M. Stephens: None.
Individual and Combined Glucose-Lowering Effects of Glucagon Receptor Antagonism and Dipeptidyl Peptidase-4 Inhibition
Authors: HAEDERSDAL SOFIE , LUND ASGER B. , NIELSEN-HANNERUP ELISABETH , MAAGENSEN HENRIK , HOLST JENS J. , KNOP FILIP K. , VILSBØLL TINA
Published: June 2018

Type 2 diabetes is characterized by absolute or relative hypoinsulinemia and hyperglucagonemia. Dipeptidyl peptidase 4 inhibitors (DPP-4i) augment insulin secretion and decrease glucagon secretion, but if glucagon is removed from the metabolic equation, the effect of DPP-4i is unknown. In a randomized, placebo-controlled, double-dummy, double-blinded, cross-over study, patients with type 2 diabetes (n=12, age [mean (SD)]: 60.9 (7.8) years, BMI 34.6 (7.1) kg/m2; HbA1c 50.3 (10.5) mmol/mol) underwent four 4-hour liquid mixed meal tests preceded by single-dose administration of 1) placebo, 2) DPP-4i (5 mg linagliptin) 2 hours before the meal, 3) glucagon receptor antagonist (GRA) (300 mg LY2409021) 12 hours before the meal, and 4) GRA + DPP-4i. Compared to placebo, fasting plasma glucose (FPG) was lowered by GRA but not DPP-4i. Adding DPP-4i to GRA did not lower FPG further. Compared to placebo, DPP-4i increased insulin responses to the meal (C-peptide AUC) (P<0.01), but did not result in a difference in plasma glucose excursions (Figure). GRA alone lowered glucose AUC, and the combination of GRA and DPP-4i lowered glucose AUC further.

In conclusion, the combination of DPP-4i and GRA has additive effects on postprandial glucose excursions. This seems to be driven by the efficient reduction in FPG by GRA combined with additional reduction in postprandial glucose excursions by DPP-4i.

Disclosure

S. Haedersdal: None. A.B. Lund: Other Relationship; Self; Novo Nordisk A/S. E. Nielsen-Hannerup: None. H. Maagensen: None. J.J. Holst: Advisory Panel; Self; Novo Nordisk A/S. Board Member; Self; Zealand Pharma A/S. Speaker's Bureau; Self; Merck Sharp & Dohme Corp., AstraZeneca. Research Support; Self; Danish Diabetes Academy, Novo Nordisk Foundation. Other Relationship; Self; Antag Therapeutics. Other Relationship; Spouse/Partner; Antag Therapeutics. F.K. Knop: Advisory Panel; Self; AstraZeneca. Consultant; Self; AstraZeneca. Research Support; Self; AstraZeneca. Speaker's Bureau; Self; AstraZeneca. Advisory Panel; Self; Eli Lilly and Company. Speaker's Bureau; Self; Eli Lilly and Company. Advisory Panel; Self; Amgen Inc.. Speaker's Bureau; Self; Merck Sharp & Dohme Corp.. Advisory Panel; Self; Novo Nordisk A/S. Consultant; Self; Novo Nordisk A/S. Speaker's Bureau; Self; Novo Nordisk A/S. Consultant; Self; Amgen Inc.. Advisory Panel; Self; MedImmune, Sanofi. Consultant; Self; Sanofi. Research Support; Self; Sanofi. Speaker's Bureau; Self; Sanofi.
Sirt5 Plays a Critical Role in Mitochondrial Protein Acylation and Mitochondrial Metabolic Homeostasis in Brown Fat
Authors: WANG GUOXIAO , MEYER JESSE G. , CAI WEIKANG , LI MENGYAO E. , SOFTIC SAMIR , KAHN C. RONALD
Published: June 2018

Brown adipose tissue (BAT) is rich in mitochondria and plays important roles in energy expenditure, thermogenesis and glucose homeostasis. Recent studies have shown that mitochondrial activity can be regulated by protein succinylation and malonylation, processes that are in part controlled by Sirt5, the major mitochondrial desuccinylase and demalonylase. Compared to other tissues, brown fat has high levels of protein malonylation and succinylation, which were further increased in mice lacking Sirt5. BAT specific Sirt5 KO mice (Sirt5-BKO) are intolerant to acute cold. Furthermore, when stressed with high fat diet or aging, Sirt5-BKO mice develop impaired glucose homeostasis. Mass Spec analysis reveals that this correlates with an increase in succinylation of a variety of mitochondria enzymes and proteins, including succinate dehydrogenase (SDH), glutamate dehydrogenase (GDH), and UCP1. Lysine to glutamine mutations of UCP1 at the two target sites, which mimic acylation, resulted in significantly decreased UCP1 activity. Likewise, hyperacylation of SDH and GDH secondary to Sirt5 deficiency also impaired their activities. The reduced function of these and other proteins in Sirt5KO BAT resulted in decreased mitochondrial membrane potential and increased accumulation of PINK1, a mitochondrial serine/threonine kinase that protect cells from stress-induced mitochondrial dysfunction. Depolarized mitochondria are often smaller in size. Consistent with this, mitochondria from BAT of Sirt5KO mice had higher Fis1 expression during fasting, leading to increased mitochondrial fission and smaller mitochondria. Thus, succinylation and malonylation of key metabolic enzymes in mitochondria is regulated by Sirt5 and plays an important role in BAT activity. Over-acylation impairs mitochondrial protein function and results in depolarized mitochondria and disturbed systemic metabolic homeostasis.

Disclosure

G. Wang: None. J.G. Meyer: None. W. Cai: None. M.E. Li: None. S. Softic: None. C. Kahn: Advisory Panel; Self; CohBar, ERX Therapeutics, AntriaBio, Inc.. Board Member; Self; Kaleio Biosciences.
Soluble RAGE Sequesters Advanced Glycation End Products following an Overnight Fast in T1DM Patients
Authors: MIRANDA EDWIN R. , FULLER JR. KELLY N. , PERKINS RYAN , BEISSWENGER PAUL J. , FARABI SARAH S. , QUINN LAURIE T. , HAUS JACOB M.
Published: June 2018

Context and Objectives: Advanced glycation end products (AGEs) promote the development of diabetic complications through activation of their receptor (RAGE). Isoforms of soluble RAGE (sRAGE) sequester AGEs and thus protect against RAGE-mediated diabetic complications. Low cellular energy, such as during fasting, activates sRAGE production. We investigated the effect of an overnight fast on circulating substrates, hormones, AGEs, and sRAGE isoforms in 26 individuals with type 1 diabetes (T1DM).

Participants and Methods: Blood was collected from young (18-30 years) T1DM patients on insulin pumps before and after an overnight fast. Circulating AGEs were measured via LC-MS/MS and sRAGE isoforms were analyzed via ELISA. eGFRcystatin-c was calculated based on circulating cystatin-c measured via ELISA.

Results: Glucose, insulin, glucagon, and eGFRcystatin-c decreased while cortisol increased following the overnight fast (p<0.05). NEFAs and cholesterol did not change (p>0.05). AGEs (CML, CEL, 3DG-H, MG-H1, and G-H1) decreased (21-58%, p<0.0001) while total sRAGE, cleaved RAGE (cRAGE), and endogenous secretory RAGE (esRAGE) increased (22-24%, p<0.0001) following the overnight fast. The changes in sRAGE isoforms were inversely related to MG-H1 (rho=-0.493 to -0.589, p<0.05) and the change in esRAGE was inversely related to the change in G-H1 (rho=-0.474, p<0.05). Multiple regression analysis revealed a 1 pg/mL increase in total sRAGE, cRAGE, and esRAGE independently predicted a 0.42-0.52 nM decrease in MG-H1.

Conclusions: Following an overnight fast, sRAGE isoforms were increased and sequestered MG-H1. Sequestration of AGEs by sRAGE has been shown to attenuate AGE/RAGE-mediated complications. Energy restriction appears to be important for protection against AGE/RAGE-mediated complications.

Disclosure

E.R. Miranda: None. K.N. Fuller: None. R. Perkins: None. P.J. Beisswenger: Employee; Self; PreventAGE Health Care, LLC.. S.S. Farabi: None. L.T. Quinn: None. J.M. Haus: None.
Resistance to Diet-Induced Obesity in Mice Lacking OPA1 in Adipose Tissue Occurs Independently of Fat-Derived FGF-21 and BAT Function
Authors: PEREIRA RENATA , OLVERA ANGELA C. , MARTI ALEX A. , HEWEZI RANA , BUI TRAN WILLIAM A. , POTTHOFF MATTHEW J. , DALE ABEL E.
Published: June 2018

Optic Atrophy 1 (OPA1) is a mitochondrial protein that regulates mitochondrial dynamics and function. The role of OPA1 in adipose tissue physiology and systemic metabolism is incompletely understood. We generated mice lacking OPA1 in adipose tissue (OPA1 Ad-KO) and demonstrated that OPA1 deletion in adipose tissue completely prevents diet-induced obesity (DIO). This metabolic protection occurs concomitantly with increased levels of FGF-21 in adipose tissue and the circulation and higher energy expenditure. In the present study, we sought to determine the contribution of fat-derived FGF-21 and brown adipocyte function to the phenotype observed in OPA1 Ad-KO mice. To test whether changes in BAT function are responsible for the resistance to DIO, soon after weaning, OPA1 Ad-KO mice were fed either 60% high-fat diet (HFD) or 10% fat diet (control diet) for 8 weeks at thermoneutral conditions (30oC), when BAT function is dampened. To test whether fat-derived FGF-21 is required for the resistance to DIO in OPA1 Ad-KO mice, we generated mice lacking both OPA1 and FGF-21 in adipose tissue, by using the cre recombinase under the control of the adiponectin promoter (DKO). We, then, fed 4-week old DKO mice either 60% HFD or 10% control diet for 4 weeks. OPA1 Ad-KO mice fed a HFD under thermoneutral conditions failed to gain weight. Diet-induced increases in total fat mass was completely prevented. Although BAT mass was equally increased in WT and Ad-KO mice, gonadal and inguinal fat pads were significantly reduced in OPA1 Ad-KO mice fed HFD. Likewise, after 4 weeks of high-fat feeding, DKO mice had significantly reduced body weight and total fat mass compared to WT mice.

In conclusion, our data suggest that reducing BAT function is not sufficient to induce fat expansion in OPA1 Ad-KO mice in response to HFD. Additionally, here we show that adipose tissue-derived FGF-21 is dispensable for the resistance to DIO observed in OPA1 Ad-KO mice.

Disclosure

R. Pereira: None. A.C. Olvera: None. A.A. Marti: None. R. Hewezi: None. W.A. Bui Tran: None. M.J. Potthoff: None. E. Abel: None.