bluuebunny/crossref_metadata_2025 huggingface dataset:
176-LB: Long-Term Glycemic Variability in Diabetic Patients According to Their Glycemic Control in Follow-Up
Authors: GARCIA-ALCALA HECTOR
Published: June 2019

Long term glycemic variability is linked to a higher rate of chronic complications and mortality in diabetic population and is also regarded a synonymous of poor glycemic control. However, the relationship between glycemic variability and glycemic control has not been studied properly.

Aims to describe differences in glycemic variability in diabetic patients according to their trends in glucose level during follow-up.

Methods from our database we selected those patients identified as diabetic (fasting glucose ≥ 126 mg/dl and/or Hba1c≥ 6.5%) who attended to our laboratory from January 2010 to august 2016 for a simultaneous Hba1c and glucose determinations. From the whole sample we selected those with at least 3 Hba1c determinations for 2 years. In all cases mean (M), standard deviation (SD) and variation coefficient (VC) were calculated from Hba1c during follow-up. Patients were categorized in four groups according to their first (i) and last determination (f) of Hba1c: group 1: i and f < 7%, group 2: i < 7% and f > 7%, group 3: i > 7% and f < 7% and group 4 i and f > 7%. We compared between groups VC.

Results we studied results from 1589 patients (men 52%, age 60.95 (SD 14.83) years, mean number of determinations: 6.65 (95% CI 6.39-6.84). The percent of patients in group 1 to 4 respectively were : 22.7%, 10.2%, 23.5% and 43.6% . The mean (SD) Hba1c i and f were for group 1: 6.33% (0.41), 6.26% (0.43), group 2: 6.30% (0.55), 8.71% (1.99) , group 3: 8.96% (2.01), 6.23% (0.49) and group 4: 9.4% (2.01), 8.78% (1.71) . Mean VC (SD) were from group 1 to 4: 9.16(9.53), 18.36(11.17), 18.37(11.41), 12.68(8.09))(p <0.05 groups 1 vs. 2,3 and 4, group 2 vs. 1, 4, group 3 vs. 1 and 4, group 4 vs. 1, 2 and 3, P NS group 2 vs. 3).

Conclusions: long term glycemic variability measured by VC is very similar in groups that migrates from their original glycemic level, no matter if their final Hba1c is within the goal. High VC is not necessarily related to poor metabolic control.

Disclosure

H. Garcia-Alcala: None.
1767-P: Inflammatory Triggers of Lipolysis Act through IRE1 in Adipocytes
Authors: FOLEY KEVIN P. , CHEN YONG , KWOK KIERAN , BARRA NICOLE G. , TAMRAKAR AKHILESH K. , LIU YONG , SCHERTZER JONATHAN D.
Published: June 2019

Hormones and inflammation can promote adipocyte lipolysis. Inflammation-induced insulin resistance can favor lipolysis, but the cellular mediators of unique lipolytic triggers are ill-defined. We found that ER stress discriminates inflammation-induced adipocyte lipolysis versus adrenergic-mediated lipolysis typical of hormones. Tauroursodeoxycholic acid (TUDCA) blocked adipocyte-autonomous lipolysis from multiple inflammatory ligands, including bacterial peptidoglycan (PGN), lipopolysaccharide (LPS) and tumor necrosis factor (TNF). TUDCA did not alter isoproterenol-induced lipolysis. Inhibiting inositol-requiring protein 1 (IRE1) kinase activity was sufficient to block lipolysis caused by inflammatory triggers and thapsigargin-induced ER stress. Tissue-specific deletion of IRE1 in mice confirmed that adipocyte-resident IRE1 was required for inflammatory ligand-induced lipolysis in adipose tissue. IRE1 kinase activity was dispensable for isoproterenol-induced lipolysis in adipocytes and adipose tissue. We found no role for typical unfolded protein responses as a mechanism linking ER stress to lipolysis, since IRE1 Rnase activity was not associated with changes in adipocyte lipolysis and adipose tissue from GRP78/BiP+/- mice had no change in lipolysis compared to littermate mice. Inhibiting IRE1 kinase activity blocked adipocyte NF-κB activation and Interleukin-6 (IL6) production in response to inflammatory ligands. However, inflammation-induced lipolysis mediated by IRE1 occurred independently from changes in insulin signaling in adipocytes, which further supported the concept that inflammatory triggers of lipolysis can work independent of hormone responses, including insulin resistance. Our results are consistent with IRE1-linked ER stress mediating an inflammation-induced lipolytic program independently from hormonal regulation of lipolysis. Targeting components of IRE1-kinase signaling may have value in obesity and inflammatory lipid disorders.

Disclosure

K.P. Foley: None. Y. Chen: None. K. Kwok: None. N.G. Barra: None. A.K. Tamrakar: None. Y. Liu: None. J.D. Schertzer: None.

Funding

Canadian Institutes of Health Research
1768-P: Inflammation in Visceral and Subcutaneous Fat and Human Insulin Resistance
Authors: MCLAUGHLIN TRACEY , ZANLEY ELIZABETH J. , PETLURA CHRISTINA I. , TOLENTINO LORNA L. , CHOI OKMI , CHUANG JESSICA , XU YUE , MORTON JOHN , ENGLEMAN EDGAR
Published: June 2019

Background/Methods: Visceral adipose tissue (VAT) is associated with increased risk for T2D and CVD. This depot, which accounts for only 5-10% of total fat mass, may play a relatively important role in determining insulin resistance (IR) due to its proximity to gut lymphatics and liver. Immune cells in fat respond to adipocyte stress and bacterial antigens from the gut with cytokine release, adversely affecting hepatic and systemic glucose metabolism. Few human studies have examined inflammation in VAT with regard to systemic IR. We hypothesized that inflammation in VAT vs. SAT would be associated with IR. To test this hypothesis we recruited 25 nondiabetic bariatric surgery patients who underwent whole-body insulin sensitivity testing via steady-state plasma glucose (SSPG) test prior to surgery. Samples of SAT and VAT were harvested for collagenase digestion and flash freezing for flow cytometry and gene expression.

Results/Conclusion: The cohort was 80% female, 20% male, age 48±10 years, BMI 43.7±6.1 kg/m2, fasting glucose 103±15 mg/dL. IR was defined as SSPG > 200, and IS as SSPG < 160 mg/dL. Comparison of immune cell profiles revealed greater frequency of macrophages in both SAT and VAT in IR vs. IS subjects, and higher expression of proinflammatory marker CD44 in IR vs. IS subjects. Macrophage number and phenotype (M1, M2, CD44+) did not differ between depots, suggesting systemic rather than localized inflammation contributes to IR.

Disclosure

T. McLaughlin: Advisory Panel; Self; January. Stock/Shareholder; Self; Eiger BioPharmaceuticals. E.J. Zanley: None. C.I. Petlura: None. L.L. Tolentino: None. O. Choi: None. J. Chuang: None. J. Morton: None.

Funding

American Heart Association
1769-P: Development of Adipose Fibrosis and Dysfunction in Aged Rxfp1-/- Mice
Authors: BENNETT ROBERT , HAMEL FREDERICK , SIMPSON RONDA L. , AGOULNIK ALEXANDER I.
Published: June 2019

The hormone relaxin has roles in insulin sensitivity and age-related fibrosis in several organs, but the effect on adipose is unknown. Given the association of adipose fibrosis to dysfunction and progression of metabolic disease, we analyzed adipose tissue in aged mice lacking the relaxin receptor RXFP1. Male and female Rxfp1-/- or age-matched wild type (WT) mice were used at full adulthood (5-7 months) or when aged (12-18 months). Total fat and lean mass was determined, then gonadal white adipose tissue (gWAT) or inguinal white adipose tissue (iWAT) was collected. Sections were stained with Sirius red to visualize collagen. Gene expression was determined by qPCR, and serum adiponectin measured by ELISA. There were no significant differences in total body fat or lean mass between WT and Rxfp1-null mice at either age. All mice had similar adipose collagen content at age 5-7 months. In aged male mice, there was a remarkable increase in collagen in the iWAT of Rxfp1-/- mice, including pericellular deposits and thick collagen fibrils, and modestly elevated gWAT collagen compared to WT. In aged female mice, Rxfp1-null mice had modestly increased pericellular collagen in iWAT, but no apparent difference in gWAT. In aged male iWAT, the expression of the collagen types I, III, and VI genes, and the lysyl oxidase genes Lox, Loxl1, and Loxl2 were all significantly elevated. Serum adiponectin was significantly reduced in Rxfp1-/- mice compared to WT (12.6±1.6 vs. 23.9±2.8 ug/ml respectively, p<.02).

In summary, Rxfp1-/- mice developed age-related adipose fibrosis, particularly in the iWAT. The effect was sex-specific, in that the fibrosis was much more extensive in male mice. The Rxfp1-/- mice had increased expression of fibrotic collagen and lysyl oxidase genes, and decreased serum adiponectin, suggesting adipose dysfunction. These results suggest that disruption of relaxin signaling plays a role in preventing age-related adipose fibrosis, which could contribute to the development and progression of metabolic dysfunction.

Disclosure

R. Bennett: None. F. Hamel: None. R.L. Simpson: None. A.I. Agoulnik: None.

Funding

U.S. Department of Veterans Affairs
1775-P: Impact of Acetyl-CoA Carboxylase 2 Inhibition on Skeletal Muscle Diacylglycerol and Ceramide Levels and Its Potential Contribution to Improved Glucose Metabolism
Authors: TAKAGI HIROYUKI , IKEHARA TATSUYA , HASHIMOTO KUMI , SHIMAZAKI ATSUYUKI , KASHIWAGI YUTO , NISHIURA YUJI , NOTOYA MITSURU , YUKIOKA HIDEO
Published: June 2019

Intramyocellular lipid (IMCL) accumulation in skeletal muscle is closely associated with the development of insulin resistance. In particular, bioactive lipids such as diacylglycerol (DAG) and ceramide (Cer) have great impact on muscle insulin action. We have recently demonstrated that inhibition of acetyl-CoA carboxylase 2 (ACC2), which negatively modulates mitochondrial fatty acid oxidation in skeletal muscle, reduced IMCL levels and improved glucose metabolism in rodents. To further investigate the underlying mechanism, we examined the impact of pharmacological ACC2 inhibition on bioactive lipid composition and metabolic functions in skeletal muscle of rats, using an ACC2 selective inhibitor, compound A. As compared with vehicle treatment, chronic treatment with compound A significantly reduced both DAG and Cer levels in skeletal muscle of nondiabetic rats, which were strongly correlated with IMCL levels. Compound A also reduced the acyl-CoA pool along with enhanced acylcarnitine formation in skeletal muscle, while there were no differences in other bioactive lipid levels and DAG or Cer synthetic gene expression levels. Similarly, in Zucker diabetic fatty (ZDF) rats, compound A reduced both DAG and Cer levels in skeletal muscle without suppressing the synthetic gene expression levels. Treatment with compound A led to improved hyperinsulinemia and upregulated expression of key regulators in energy metabolism, such as Glut4 and Pgc1α, in skeletal muscle. Moreover, these positive effects on glucose metabolism were strongly correlated with diacylglycerol and ceramide reductions. Collectively, these findings suggest that ACC2 inhibition leads to preferential reductions of DAG and Cer by directly decreasing acyl-CoA pool via fatty acid oxidation in skeletal muscle, and these lipid reductions are closely linked to the improvement of glucose metabolism by ACC2 inhibition.

Disclosure

H. Takagi: None. T. Ikehara: None. K. Hashimoto: None. A. Shimazaki: None. Y. Kashiwagi: None. Y. Nishiura: None. M. Notoya: None. H. Yukioka: None.
1780-P: In High-Fat Diet-Induced Mice Skeletal Muscles, Iron Overload Plays a Critical Role in Leading Insulin Resistance
Authors: CHOI SUNGE , LEE NAMI , MOON HYUN UK , KIM HAE JIN , JEON JA YOUNG , KANG YUP , KIM TAE HO , LEE KWANWOO
Published: June 2019

Aim/Hypotheses: Iron plays an important role in many physiological processes, including redox balance, inflammation, and mitochondrial respiratory metabolism. Abnormalities in iron metabolism lead to insulin resistance as well as diabetes. However, the abnormal mechanism of iron metabolism in the muscles of insulin resistance animal models is not precisely well known. Therefore, we investigated the molecular mechanism underlying iron dysregulation in high fat diet-induced C57BL/6J mice skeletal muscles.

Methods: We measured intracellular iron content in skeletal muscle tissues and iron metabolism related protein levels, such as transferrin receptor1, heavy chain ferritin, light chain ferritin, DMT1, and ferroportin. To investigate the association between iron content and insulin resistance, we treated iron donor or chelator in an animal model and performed insulin tolerance tests and measurement of insulin signaling.

Results: Interestingly, intracellular iron levels were increased in high fat diet-induced mice skeletal muscles. We also observed up-regulation of transferrin receptor 1 (TfR1), ferritin, but did not observe a change of DMT1 and ferroportin. Treatment with iron dextran, an iron donor, in C57BL/6J normal mice induced insulin resistance. However, treatment of desferrioxamine, an iron chelator, in high fat diet-induced insulin resistance mice recovered insulin resistance. Iron overload with iron dextran impaired insulin signaling in skeletal muscles, while iron chelation with desferrioxamine recovered high fat-induced dysregulated insulin signaling.

Conclusions/interpretation: Therefore, we consider fine-tuning of skeletal muscle iron levels and highly suggest the use for preventing and/or treating insulin resistance and diabetes.

Disclosure

S. Choi: None. N. Lee: None. H. Moon: None. H. Kim: None. J. Jeon: None. Y. Kang: None. T. Kim: None. K. Lee: None.
1782-P: Mechanism of Lipid-Induced White Adipose Tissue Insulin Resistance
Authors: ZHANG YE , ZHANG DONGYAN , LYU KUN , SONG JOONGYU D. , LI XIRUO , PERRY RACHEL J. , SAMUEL VARMAN , SHULMAN GERALD I.
Published: June 2019

White adipose tissue (WAT), as an energy storage organ, plays a major role in regulating peripheral insulin resistance and hepatic gluconeogenesis, but the mechanism by which lipid induces insulin resistance in WAT is poorly understood. To examine the potential role of the diacylglycerol (DAG) - protein kinase Cε (PKCε) - insulin receptor (INSR) pathway in mediating lipid-induced WAT insulin resistance, we assessed insulin action in liver, muscle and WAT in 7-day high fat diet (HFD) and regular chow (RC) fed rats by hyperinsulinemic-euglycemic clamp (HEC) combined with [3-3H] glucose, [14C] deoxyglucose and [2H5]glycerol infusions. Using this approach, we found that HFD induced WAT insulin resistance as reflected by impaired suppression (∼20%, P<0.05 vs. RC) of WAT lipolysis during the HEC. WAT insulin resistance was associated with increased PKCε translocation (P<0.05 vs. RC) and increased phosphorylation of perilipin, HSL and ATGL (all P<0.05 vs. RC). To investigate if PKCε induced Thr1150phosphorylation mediates lipid-induced WAT insulin resistance by inhibiting INSR kinase activity, we studied mice with a threonine-to-alanine knockin mutation at INSR Thr1150(InsrT1150Amice). InsrT1150Amice were protected from HFD-induced WAT insulin resistance as reflected by normalization of insulin’s ability to suppress WAT lipolysis and normalization of insulin’s ability to stimulate INSR and Akt2 phosphorylation in WAT, as well as a restoration of insulin’s ability to suppress phosphorylation of perilipin, HSL and ATGL (all P<0.05 vs. WT).

Conclusion: The DAG-PKCε-INSR Thr1150pathway plays a major role in mediating lipid-induced WAT insulin resistance and represents a potential therapeutic target to improve insulin sensitivity in WAT.

Disclosure

D. Zhang: None. K. Lyu: None. J.D. Song: None. X. Li: None. R.J. Perry: Research Support; Self; AstraZeneca. V. Samuel: None. G.I. Shulman: Advisory Panel; Self; AstraZeneca, Janssen Research & Development, Merck & Co., Inc. Advisory Panel; Spouse/Partner; Merck & Co., Inc. Board Member; Self; Novo Nordisk A/S. Consultant; Self; Aegerion Pharmaceuticals, IMetabolic BioPharma Corporation, Longitude Capital, Nimbus Discovery, Inc., Staten Biotechnology B.V.

Funding

National Institutes of Health (R01DK116774)
1797-P: ß-arrestin-1 in AgRP Neurons Plays Crucial Role in Maintaining Whole Body Glucose Homeostasis
Authors: PYDI SAI PRASAD , CUI ZHENZHONG , BARELLA LUIZ F. , CUI YINGHONG , CHEN WEI , GAVRILOVA OKSANA , WESS JÜRGEN
Published: June 2019

Hunger and satiety are regulated, to a major extent, by the agouti-related protein (AgRP)/neuropeptide Y (NPY) and proopiomelanocortin (POMC) neurons residing in the arcuate nucleus of the hypothalamus. During starvation, AgRP neurons are strongly activated to promote hunger. Peripheral hormones and nutrients regulate the function of AgRP neurons, thus ensuring proper glucose and energy homeostasis. Recent studies from various labs, including our group, have shown the importance of G-protein coupled receptors (GPCRs) in regulating the activity of AgRP neurons. GPCR function is modulated by a pair of proteins known as beta-arrestin-1 and -2 (barr1 and barr2, respectively), which can terminate GPCR signaling and/or mediate GPCR-independent signaling. It is well established that barr1 and barr2 are involved in many important physiological functions. However, the potential roles of barr1 and barr2 in regulating the activity of AgRP neurons remain unexplored. To address this issue, we generated mice that lacked barr1 or barr2 selectively in AgRP neurons using Cre/loxP-flex-switch technology. Interestingly, AgRP-barr1-KO mice consuming a high fat diet showed significantly impaired glucose tolerance, decreased insulin sensitivity, and elevated plasma glucose and insulin levels. AgRP-barr1-KO mice did not differ from their control littermates in body weight and food intake. More detailed studies into the mechanisms through which barr1 regulates the activity of AgRP neurons may lead to new strategies to alter the activity of AgRP neurons for therapeutic purposes.

Disclosure

S. Pydi: None. Z. Cui: None. L.F. Barella: None. Y. Cui: None. W. Chen: None. O. Gavrilova: None. J. Wess: None.
180-OR: Tissue-Specific Functions of PPARα Overexpression in Liver, Adipose, and Pancreatic ß Cells
Authors: YE RISHENG , SCHERER PHILIPP E.
Published: June 2019

Peroxisome proliferator-activated receptor (PPAR) α is one of the master regulators of lipid metabolism and the major target of fibrates, a class of drugs improving dyslipidemia in metabolic syndromes. To understand the tissue-specific roles of PPARα and the coordination among multiple organs, we employed newly generated mouse models enabling doxycycline-inducible overexpression of PPARα specifically in liver, adipose or the insulin-producing pancreatic β-cells. Titrated by doxycycline dose, a moderate elevation of PPARα proteins in liver activated the transcription of its target genes. In mice with diet-induced obesity, hepatic overexpression of PPARα significantly reduced steatosis and improved systemic insulin sensitivity. Surprisingly, systemic triglyceride clearance was dramatically impaired, associated with a trend towards faster VLDL secretion. PPARα overexpression in adipose tissues had a marginal effect on systemic insulin sensitivity. However, inflammation was markedly ameliorated in white but not brown fat pads. Pancreatic β-cell-specific overexpression of PPARα resulted in a significant decrease in glucose-stimulated insulin secretion, suggesting a negative impact of PPARα induction on β-cell function. Taken together, our findings reveal the differential actions of enhanced PPARα on local tissues and whole-body metabolism and call for caution to the potential adverse effects from fibrate treatment. Further dissection of PPARα signaling with our mouse models may facilitate the discovery of novel therapeutic targets with high efficacy and specificity.

Disclosure

R. Ye: None. P.E. Scherer: None.

Funding

National Institutes of Health (R01DK55758, R01DK099110, P01-DK088761-01); JDRF (17-2012-36); Novo Nordisk Foundation (to P.E.S.)
1809-P: Comparing Male and Female Metabolic Phenotypes in Mouse Strains Deficient in Leptin Signaling
Authors: FRENCH RICHARD D. , LEIGHTON KRYSTAL , SERRANO JASON , SCHILE ANDY
Published: June 2019

National Institutes of Health policy states that animal studies should account for sex as a biological variable by including males and females when possible. Male mice are mainly used in diabetes research involving mutations that inactivate the leptin hormone (Lepob) or its receptor (Leprdb). We found that many metabolic phenotypes were similar in males and females from two C57BL/6J mutant strains with transient hyperglycemia (B6-ob and B6-db) and a C57BLKS/J strain with sustained hyperglycemia (BKS-db). In all strains, homozygous ob or db genotypes led to similar male and female weight gain despite sexual dimorphism in weights of control genotypes. In homozygous mutant mice at 8 and 16 weeks of age, the only significant weight differences between males and females were at 8 weeks in B6-db (males weighed 1.7 g more; P = 0.0037) and 16 weeks in B6-ob (females weighed 2.5 g more; P = 0.0017). BKS-db/db males had higher nonfasted blood glucose than females (415 mg/dL vs. 357 mg/dL; P < 0.0001) at 8 weeks, but no other differences were significant at 8 and 16 weeks. Male and female B6-ob/ob and B6-db/db mice reverted to normal blood glucose at similar rates. HbA1c levels were higher in males for all strains at 16 weeks (P < 0.05 for all 3 pairwise comparisons). Male and female mutants had similar body fat percentages, with the exception of higher adiposity in B6-ob/ob females at 16 weeks (6% greater; P = 0.0163). We assessed serum insulin and leptin in BKS-db mice. Insulin was significantly higher in male and female db/db mice relative to db/+ or +/+ controls at 8 weeks, but db/db levels did not differ by sex. Leptin was significantly higher in db/db mice relative to controls (P < 0.0001 for all pairwise comparisons). Leptin did not differ by sex in db/db mice at 8 weeks; leptin levels were significantly higher in females at 16 weeks of age (P = 0.0039). All data will be made publicly available from the Mouse Phenome Database to serve as reference values when considering the use of female ob and db mutant mice in diabetes research.

Disclosure

R.D. French: None. K. Leighton: None. J. Serrano: None. A. Schile: None.
1811-P: Short Term Dopamine D1D2 Receptor Agonist Therapy Induces Long-Term Amelioration of Hyperglycemia in ob/ob Mice
Authors: LUO SHUQIN , EZROKHI MICHAEL , COMINOS NICHOLAS , RAICHE BENJAMIN , CINCOTTA ANTHONY H.
Published: June 2019

Short term, circadian-timed dopamine precursor (L-DOPA) therapy can produce long term advances or delays in the annual cycle of metabolism in several seasonal vertebrate species as function of the time of day of its administration. It has also been demonstrated that dopamine D1 plus D2 receptor agonist (DA) therapy improves dysmetabolism in leptin inactive animal models of metabolic syndrome to a level that cannot be achieved with either agonist alone. This study therefore investigated the potential for short term DA therapy to induce long term reduction in hyperglycemia in ob/ob mice. In two separate studies, animals were treated either with the dopamine D1 plus D2 agonists (SKF38393 and bromocriptine, respectively) (each 10 mg/kg BW ip) or vehicle prior to the onset of waking for 14 days. After 7 and 11 days of treatment, DA markedly reduced plasma hyperglycemia, triglyceride and FFA levels, and elevated corticosterone levels (Study 1). Remarkably, these DA effects remained 28 days after cessation of the therapy. In Study 2, conducted to assess DA effects on impaired glucose intolerance (IGT), DA therapy again produced long-lasting improvements in hyperglycemia and IGT (Table). This study demonstrates a long-lasting amelioration of dysglycemia in ob/ob mice with a systemic therapy. These studies provide a basis for contemplating development of a clinical DA therapy for metabolic disease.

Disclosure

S. Luo: Employee; Self; VeroScience LLC. M. Ezrokhi: Employee; Self; VeroScience LLC. N. Cominos: Employee; Self; VeroScience LLC. B. Raiche: Employee; Self; VeroScience LLC. A.H. Cincotta: Employee; Self; VeroScience LLC.
1813-P: An Experimental Model to Combat the Increased Prevalence of Diabetes in Alzheimer’s Disease
Authors: BABICI DENIS , ZHANG JIE , OYDANICH MARKO , NISHIMURA KOICHI , VATNER DOROTHY E. , MOURADIAN M. MARAL , VATNER STEPHEN F.
Published: June 2019

Alzheimer’s disease is associated with many other disorders of healthful aging; one of the most prominent is the increased prevalence of diabetes in patients with Alzheimer’s, resulting in almost twice the number of hospitalizations compared with that of non-Alzheimer’s patients. The goal of this investigation was to discover an animal model that was protected both from Alzheimer’s Disease and diabetes. The adenylyl cyclase type 5 (AC5) knockout (KO) was selected since it not only lives a third longer than its wild type (WT), but is also a model of healthful aging, with improved metabolism, enhanced exercise capacity and protection against obesity and diabetes. Accordingly, we compared the AC5 KO with that of the J20 mouse, a model for Alzheimer’s disease. Comparisons were made among AC5 KO, J20 and WT mice for behavioral tests indicative of Alzheimer’s and diabetes protection as reflected by the glucose tolerance test. All 3 behavioral tests studied demonstrated that AC5 KO were protected compared to WT, whereas the J20 mice demonstrated behavioral alterations consistent with Alzheimer’s Disease. For example, the water maze test, used to assess spatial learning and memory, demonstrated the expected 134± 7.6% deficit, p<0.05, in the J20 mice, in contrast to the 38± 3.0% improvement, in performance, p<0.05, in AC5 KO. The glucose tolerance test (GTT) also demonstrated protection in AC5 KO and impaired GTT in the J20 mice, i.e., the area under the curve following 1g/kg IP glucose, was 47± 5.2% less, p<0.05, in AC5 KO compared to WT, whereas it was 137± 10.2% higher, p<.05, than WT in the J20 mice. Thus, the AC5 KO mice were protected both against impaired GTT and behavioral changes associated with Alzheimer’s disease, suggesting that inhibition of AC5 would be a novel therapeutic modality, not only for diabetes, but also for the diabetes associated with Alzheimer’s Disease.

Disclosure

D. Babici: None. J. Zhang: None. M. Oydanich: None. K. Nishimura: None. D.E. Vatner: None. M. Mouradian: None. S.F. Vatner: None.

Funding

National Institutes of Health (R01HL102472, R01HL106511, R01HL119464, R01HL124282, R01HL130848, R01HL137368, R01HL137405, R21AG053514)
182-OR: Maternal Glucose and Insulin Are Associated with Lipid Metabolism and Adipogenesis Pathways in Human Umbilical Cord-Derived Mesenchymal Stem Cells: The Healthy Start Echo Cohort
Authors: KELEHER MADELINE , DABELEA DANA , FRIEDMAN JACOB E. , BOYLE KRISTEN E.
Published: June 2019

We have reported that umbilical cord mesenchymal stem cells (MSCs) from infants born to mothers with obesity have less AMP-activated protein kinase [AMPK] and less inhibitory phosphorylation of glycogen synthase kinase 3 [GSK3]β, a regulator of MSC differentiation. This is accompanied by a greater capacity for in vitro adipogenesis, which positively correlates with infant adiposity. Here we hypothesized that, independent of maternal pre-pregnancy (pp)BMI, maternal glucose and insulin would be associated with GSK3β and AMPK in undifferentiated infant MSCs. We studied 67 women (ppBMI 18-42 kg/m2) at mid (15-23 weeks) and late (24-32 weeks) gestation without preeclampsia or gestational diabetes, as well as their infants’ MSCs. We ran linear models to test the effect of fasting maternal glucose and insulin on each phosphorylated MSC protein, with infant sex and gestational age as covariates, ± ppBMI as a covariate to account for collinearity with metabolic measures. Linear model p-values and Pearson correlations are reported. Maternal glucose at mid (p = 0.03, r = 0.26) and late (p = 0.009, r = 0.35) gestation had a significant effect on AMPKThr172, with no effect of ppBMI, indicating greater AMPK activity with higher maternal glucose. Mid gestation insulin (p = 0.04, r = -0.21) was associated with GSK3βSer9, with the same trend for HOMA-IR—but not when ppBMI was included as a covariate, as it was also negatively associated with GSK3βSer9 (p = 0.02, r = -0.24), showing collinearity of ppBMI and insulin (r = 0.40). This signifies higher ppBMI and insulin with less GSK3β inhibition, which we have previously linked to greater adipogenesis. These results demonstrate the novel finding that maternal glucose during pregnancy is associated with perturbations to lipid metabolism pathways in infant MSCs across a wide range of ppBMI, giving important clues as to how maternal metabolism may impact infant metabolic disease risk.

Disclosure

M. Keleher: None. D. Dabelea: None. J.E. Friedman: Consultant; Self; Janssen Research & Development. K.E. Boyle: None.

Funding

National Institutes of Health (4UH3OD023248-03)
1824-P: Leptin Receptor Neurons in the Hypothalamic Ventromedial Nucleus Play a Physiological Role in Regulating Glucose Tolerance
Authors: FABER CHELSEA L. , HARVEY TRISTA J. , VELASCO KEVIN R. , DAMIAN VINCENT , SCHWARTZ MICHAEL W. , MORTON GREGORY J.
Published: June 2019

A role for leptin receptor (LepR)-expressing neurons in the hypothalamic ventromedial nucleus (VMN) in glucose homeostasis is suggested by studies in which leptin is administered into, or leptin receptors are deleted from, this brain area. However, whether LepR neurons in the VMN play a physiological role in glycemic control remains unknown. To test this hypothesis, we utilized an optogenetics approach to acutely silence VMNLepR neurons in awake, freely moving mice. We found that while photoinhibition of VMNLepR neurons had no effect on blood glucose levels under basal conditions (Control AUC: 681.6 ± 422.4 vs. Inhib AUC: 565.8 ± 350.7; p=ns, n=10), it impaired glucose tolerance significantly (Control AUC: 9251.7 ± 2032.6 vs. Inhib AUC: 13957.4 ± 4837; p<0.01, n=10). Further, this effect occurred despite no change in glucose-stimulated insulin secretion (GSIS), suggesting that the effect is not secondary to reduced insulin secretion. Consistent with this conclusion, we report that insulin sensitivity was reduced by inhibition of VMNLepR neurons based on insulin tolerance testing (Control AUC: 8341 ± 531 vs. Inhib AUC: 9138 ± 658; p<0.01, n=9). Together, these data suggest that VMNLepR neurons play a physiological role in the control of glucose tolerance and that activity of these neurons is required for normal insulin sensitivity. Future studies will examine both the peripheral mechanism(s) that mediate these effects and to identify the underlying neurocircuitry.

Disclosure

C.L. Faber: None. T.J. Harvey: None. K.R. Velasco: None. V. Damian: None. M.W. Schwartz: Consultant; Self; Novo Nordisk A/S. Research Support; Self; Novo Nordisk A/S. G.J. Morton: None.

Funding

National Institutes of Health
1836-P: Derivation of Glucagon Kinetics to Reconstruct Glucagon Secretion in Nondiabetic Humans
Authors: LAURENTI MARCELLO C. , MAN CHIARA DALLA , ADAMS J.D. , EGAN AOIFE M. , COBELLI CLAUDIO , VELLA ADRIAN
Published: June 2019

Impaired glucose tolerance arises out delayed and decreased postprandial insulin secretion together with impaired postprandial suppression of glucagon. Recent studies have demonstrated that β-cell and α-cell dysfunction can occur independently in prediabetes. The effect of diabetes-associated variation in TCF7L2 on α-cell function also suggests a direct role in the pathogenesis of type 2 diabetes (T2DM). Quantification of the relative contribution of α-cell and β-cell function to glucose tolerance has been lacking because of a dearth of information regarding glucagon kinetics in humans. This information is necessary to deconvolute glucagon secretion from peripheral glucose concentrations. Therefore, as part of a series of experiments examining the interaction between a lack of glucagon suppression with intact, mildly or moderately impaired insulin secretion we studied 22 nondiabetic subjects (age = 46 ± 3 years, BMI = 29 ± 1 Kg/M2). An intravenous glucose infusion mimicking the systemic appearance of 50g oral glucose was administered in the presence of a pancreatic clamp over 300 minutes. Glucagon was infused at a rate of 0.65ng/kg/min, starting 120 minutes after initiation of the experiment (and suppression of endogenous glucagon secretion by somatostatin). The observed glucagon appearance rates were used to calculate the kinetic parameters of glucagon. Volume of distribution (Vd) was estimated at 14 ± 2 Litres or 0.16 ± 0.02 L/Kg body weight. Half-life was estimated at 6.1 ± 0.5 minutes with a clearance rate (CL) of 1.6 ± 0.1 L/min. Body surface area and height predicted Vd and CL. The individual parameters were then used to calculate glucagon secretion rates from peripheral glucagon concentrations for each participant. Fasting glucagon secretion rates (101 ± 11 ng/min) decreased (p < 0.01) in the presence of somatostatin (57 ± 5 ng/min). These data demonstrate the application of deconvolution to the quantification of glucagon secretion and its contribution to glucose tolerance.

Disclosure

M.C. Laurenti: Employee; Self; GlySens Incorporated. C. Dalla Man: None. J. Adams: None. A.M. Egan: None. C. Cobelli: None. A. Vella: Advisory Panel; Self; vTv Therapeutics. Research Support; Self; Novo Nordisk Inc.

Funding

National Institutes of Health
1843-P: Reduced Sampling for the Estimation of Hepatic and Extrahepatic Insulin Clearance in Children of Different Ethnicities
Authors: PICCININI FRANCESCA , GOWER BARBARA , FERNANDEZ JOSE R. , BERGMAN RICHARD N.
Published: June 2019

African American (AA) children have lower hepatic insulin clearance than European Americans (EA), as obtained with a 25-sample intravenous glucose tolerance test (FSIGT), over 240 minutes (t=0, 2, 3, 4 5, 6, 8, 10, 12, 15, 19, 20, 21, 22, 24, 26, 28, 30, 35, 40, 50, 60, 70, 180, 240 minutes). C-peptide and insulin concentrations were analyzed with a recent model of hepatic (FEL) and extra-hepatic (CLP) insulin clearance. This model has not been tested in a reduced sampling protocol, easier to be performed in larger cohorts. With data from 203 children of both sexes and 3 ethnic groups [55 AA, 88 EA, 60 HA (Hispanic Americans), age 7-13 years, mean BMI = 19 kg/m2, basal plasma glucose = 99 mg/dL, insulin = 78 pmol/L, C-peptide = 511 pmol/L], a reduced 12-sample schedule was examined (t=0, 2, 4, 8, 19, 22, 26, 30, 40, 50, 70, 180 minutes). FEL and CLP from the reduced protocol were strongly correlated with the full one: FEL: r=0.91, p<0.001; CLP: r=0.96, p<0.001. The mean precision of estimates (coefficient of variation, CV) was similar: CVfull=40%, CVreduced=41%. The lower hepatic but not extra-hepatic insulin clearance in AA vs. EA children was still detectable with the reduced sampling (see Figure 1), that provides virtually identical and precise estimates of insulin clearance. This reduced protocol can be used in larger population-based studies.

Disclosure

F. Piccinini: None. B. Gower: None. J.R. Fernandez: None. R.N. Bergman: Consultant; Self; Zafgen, Inc.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (DK067426); Nutrition Obesity Research Center (DK56336); National Institutes of Health (M01RR00032)
1844-P: Long-Term Remission of Type 2 Diabetes after Weight Loss Requires Effective Clearance of Hepatic VLDL-TG and Maintenance of Low Intrapancreatic Fat
Authors: AL-MRABEH AHMAD , ZHYZHNEUSKAYA SVIATLANA V. , BARNES ALISON C. , HOLLINGSWORTH KIEREN G. , SATTAR NAVEED , LEAN MICHAEL E. , TAYLOR ROY
Published: June 2019

The Diabetes Remission Clinical Trial (DiRECT) demonstrated initial remission of type 2 diabetes in about half of a large primary care population, and this was associated with decrease in intrapancreatic fat content and return of beta cell function. We have carried out detailed metabolic studies on a subgroup at 2 years, comparing those who remained in remission (HbA1c <6.5%; n=20, 7F/13M, 54.6±7.3 years, BMI 34.5±4.9kg/m2), and those who failed to maintain the initial remission (n=13, 6F/7M, 52.6±8.3 years, BMI 34.9±3.7kg/m2). Pancreas and liver fat were quantified by 3-point Dixon MRI. Hepatic VLDL-triglyceride (VLDL1-TG) production was measured in vivo using a non-isotopic competitive blocking method. Remission of diabetes was associated with major decreases in liver fat, pancreas fat, and hepatic VLDL-TG production during the weight loss phase between baseline to 5 months in both groups. However, those who failed to maintain remission were characterized by more weight regain (11. 3±1.9 vs. 6.6±1.0 kg, p=0.036), and greater increases in both liver (6.2±1.1 vs. 3.6±0.9%, p=0.05), and pancreas fat (+1.0±0.39 vs. -0.48±0.25%, p=0.005) between 5 months and 24 months. Hepatic VLDL-TG pool level remained stable under remission conditions (1046.4± 204.6 to 1638.6± 372.11 mg, p=0.35), whereas there was a significant increase when remission was lost (1328.0± 271.8 to 2865.6±692.4mg, p=0.04). In those who failed to maintain remission, fasting VLDL-TG increased (0.46±0.10 to 0.84±0.17 mmol/l, p<0.05), and there was a positive correlation between the rise in liver fat and intrapancreatic fat (r=0.64, p=0.018). These data emphasize the link between hepatic VLDL-TG-metabolism and accumulation of fat within the liver and pancreas in the pathogenesis of type 2 diabetes, provide further evidence for the role of fat in its pathophysiology, and show that longer term remission of type 2 diabetes is dependent upon avoidance of weight regain.

Disclosure

A. Al-Mrabeh: None. S.V. Zhyzhneuskaya: None. A.C. Barnes: None. K.G. Hollingsworth: None. N. Sattar: Advisory Panel; Self; Amgen Inc., AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Novo Nordisk A/S. Consultant; Self; NAPP Pharmaceuticals Limited. Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc. Speaker's Bureau; Self; Amgen Inc., Eli Lilly and Company, Mitsubishi Tanabe Pharma Corporation, Novo Nordisk A/S, Roche Diagnostics France, Sanofi. M.E. Lean: Consultant; Self; Counterweight Ltd., Novo Nordisk A/S. Research Support; Self; Novo Nordisk A/S. R. Taylor: Advisory Panel; Self; Wilmington Healthcare. Speaker's Bureau; Self; Lilly Diabetes, Novartis AG.

Funding

Diabetes UK
1847-P: SGLT2 Inhibition Reduces Paternal Intergenerational Transmission of Metabolic Disease in Mice with Dietary Obesity
Authors: OSATAPHAN SORAVIS , CHIMENE-WEISS JEREMY , MACCHI CHIARA , SU LEI , LORANGER NICOLE , KRITSANAVIPARKPORN CHAWAN , KOZUKA CHISAYO , PATTI MARY E.
Published: June 2019

Risk for metabolic disease can be transmitted via both the maternal and paternal lineage, potentially through both genetic and non-genetic mechanisms. This may contribute to the exponential rise in obesity and type 2 diabetes worldwide. We hypothesized that preconception interventions to improve paternal metabolism could improve offspring health and reduce adult offspring metabolic disease. We have developed a model of glucolipotoxicity, induced by chronic overnutrition, and its reversal by SGLT2 inhibitors (SGLT2i). Male C57BL/6J mice fed a 60% high fat diet (HFD) were subjected to (1) continued HFD ad libitum (HFD), or (2) HFD ad libitum, supplemented with canagliflozin (CANA, 30mg/kg/day) for 4 weeks. CANA significantly (1) reduced body weight and hepatic steatosis, (2) improved glucose tolerance and (3) reprogrammed hepatic transcription to favor catabolism in adult males. HFD and CANA males were bred with control females, and offspring were fed chow diet ad libitum throughout life. At 13 months male offspring of CANA-treated fathers had 18% lower body weight and 32% lower fat mass (all p<0.05, vs. offspring of HFD fathers). Improved glucose tolerance and improved insulin sensitivity were also observed at age 9-12 months (26% and 18% lower AUC respectively, P<0.05). Remarkably, at 13 months all male offspring of HFD-exposed fathers had mild to severe liver steatosis; however, 57% of CANA-treated fathers were free of liver steatosis. At a transcriptional level, expression of genes encoding key lipogenic enzymes (e.g., Fasn, Pkl and Scd1) were reduced in offspring of CANA-treated males Together these data demonstrate that improvement of paternal metabolism prior to conception protects against obesity, hepatic steatosis, and diabetes risk later in life in offspring.

Disclosure

S. Osataphan: None. J. Chimene-Weiss: None. C. Macchi: None. L. Su: None. N. Loranger: None. C. Kritsanaviparkporn: None. C. Kozuka: None. M.E. Patti: Consultant; Self; Eiger BioPharmaceuticals. Research Support; Self; Dexcom, Inc., Janssen Pharmaceuticals, Inc., MedImmune, Xeris Pharmaceuticals, Inc.

Funding

National Institutes of Health
185-LB: Repeatability and Reproducibility of Pancreas Volume Measurements Using MRI
Authors: WILLIAMS JONATHAN M. , HILMES MELISSA A. , ARCHER BRANCH T. , DU LIPING , KANG HAKMOOK , RUSSELL WILLIAM E. , MOORE DANIEL J. , POWERS ALVIN C. , VIROSTKO JOHN
Published: June 2019

Pancreas volume, as measured by magnetic resonance imaging (MRI), is smaller in individuals with newly-diagnosed type 1 diabetes (T1D) and declines over the first year after diagnosis. However, the repeatability and reproducibility of these MRI measurements is not established, and for MRI to be utilized to measure pancreas volume, the variation between measurements of pancreas volume must be determined. To determine the test-retest repeatability of pancreas volume measurements by MRI, we performed two or three same-day repeat MRIs in the same individuals with or without T1D (n = 8, mean age 24 y, range 11-40 y). A single radiologist, blinded to whether the subject had T1D or not, outlined the pancreas on these repeat images. Pancreas volume was determined by multiplying the area of the pancreatic regions of interest by the MRI slice volume (5 mm). The repeatability of test-retest scans had an intraclass correlation coefficient (ICC) of 0.979 (95% CI 0.928 to 0.996). To determine the inter-reader reliability of pancreas volume measurements, the pancreas was independently outlined by two board-certified radiologists (n = 11). Comparing results from multiple radiologists yielded an ICC of 0.931 (95% CI 0.776 to 0.981), with greater differences in measurement in larger pancreases (p < 0.005). The mean DICE coefficient, a measurement of the degree overlap between pancreas regions of interest between the two readers, was 0.77. These data show that measurements of pancreas volume obtained using MRI are both repeatable and reproducible across multiple readers with ICCs corresponding to excellent clinical significance (ICC > 0.9). These results indicate that MRI measurements of T1D pancreatic volume can be reliably determined and could be useful for clinical investigation.

Disclosure

J.M. Williams: None. M.A. Hilmes: None. B.T. Archer: None. L. Du: None. H. Kang: None. W.E. Russell: None. D.J. Moore: None. A.C. Powers: None. J. Virostko: None.

Funding

JDRF (3-SRA-2015-102-M-B)
1859-P: Autophagy Promotes Gluconeogenesis in Hepatocytes through Forkhead/winged Helix Transcription Factor (FoxO1) Biosynthesis by Supporting Intracellular Amino Acids Turnover
Authors: SHEN ZHENG , PAN QUAN , YANG WANBAO , CHEN YUNMEI , LI XIAOPENG , AI WEIQI , GUO SHAODONG
Published: June 2019

Autophagy is one of cellular survival mechanisms under starvation condition. When eukaryotic cells are in poor nutritional state, such as starvation, cells tend to utilize intracellular autophagic substrates (e.g., defective, surplus or damaged cellular macromolecules, or organelles) to generate building blocks such as amino acids for temporal adaptation to adverse condition. The forkhead/winged helix transcription factor FoxO1 promotes hepatic glucose production (HGP) by increasing expression of genes responsible for gluconeogenesis. In this study, we propose a possible mechanism how autophagy regulates gluconeogenesis in hepatocytes under starvation condition. Using an autophagy inhibitor, chloroquine (CQ) and mice primary hepatocytes, we found that HGP was suppressed under autophagy deficiency. Interestingly, the effect of autophagy inhibitor on HGP suppression was significantly reduced in FoxO1-knockout mice primary hepatocytes. Furthermore, autophagy deficiency decreased FoxO1 protein amount and expression of genes encoding gluconeogenesis rate-limiting enzymes Pck1 and G6pc, but barely affected FoxO1 mRNA level and FoxO1-S253 phosphorylation. Immunofluorescent data also suggested that less FoxO1 was translocated into nuclear under CQ-treatment. By analyzing the amino acid profile in hepatocytes in vitro with HPLC, we found that CQ-treatment significantly decreased the concentration of amino acids for leucine, isoleucine, alanine, phenylalanine, tyrosine, glutamine, glycine and valine. Importantly, when complete 20 amino acids mixture was added in CQ-treated hepatocytes under starvation, the reduction of FoxO1 protein levels was largely attenuated. Thus, we conclude that autophagy regulates gluconeogenesis in hepatocytes through supporting intracellular amino acids turnover which helps biosynthesis of FoxO1.

Disclosure

Z. Shen: None. Q. Pan: None. W. Yang: None. Y. Chen: None. X. Li: None. W. Ai: None. S. Guo: None.

Funding

American Diabetes Association (1-15-CD-09 to S.G.)
1864-P: p38α MAPK Mediates Glucagon-Induced Hepatic Glucose Production through Phosphorylation of Foxo1 at Ser273
Authors: YANG WANBAO , AI WEIQI , LI XIAOPENG , PAN QUAN , SHEN ZHENG , CHEN YUNMEI , SUN YUXIANG , GUO SHAODONG
Published: June 2019

Glucagon is involved in glucose homeostasis via triggering gluconeogenesis and glycogenolysis. In addition to activation of protein kinase A (PKA), p38α MAPK (p38) is activated by glucagon and promotes glucagon-induced hepatic glucose production. However, underlying mechanisms by which p38 mediates the effect of glucagon are not well elucidated. Previously, we established that glucagon increases the phosphorylation of Foxo1 at Ser273 via PKA to promote hepatic glucose production. In this study, we investigated the potential role of p38 in the action of glucagon by phosphorylation of Foxo1 at Ser273. Using the mouse primary hepatocytes, we showed that activation of p38 by glucagon promoted phosphorylation of Foxo1 at Ser273, which results in both increased stability and nuclear translocation of Foxo1. In vivo kinase assay shows that the active p38 enzyme increased the phosphorylation of Foxo1 at Ser273. Moreover, p38 promoted glucagon-induced PKA activity to increase the phosphorylation of Foxo1 at Ser273. Suppression of p38 by siRNA and SB203580 decreased hepatic glucose production by glucagon in control mouse primary hepatocytes; however, such an effect was diminished in the hepatocytes isolated from the Foxo1-S273D knock-in mice, where Foxo1-Ser273 was replaced by the aspartate mutation (D). In mice, we further showed that injection of p38 inhibitor SB203580 decreased the fasting blood glucose and hepatic glucose production in wild type control mice, while this effect was not observed in Foxo1-S273D mice. These results revealed the novel role of p38 in control of Foxo1 phosphorylation at Ser273 to regulate the action of glucagon in glucose homeostasis.

Disclosure

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

Funding

American Diabetes Association (1-15-CD-09 to S.G.); National Institutes of Health (R01DK095118)