bluuebunny/crossref_metadata_2025_split huggingface dataset:
Siah2 Expression in Adipocyte Progenitor Cells
Authors: DANG THANH , KILROY GAIL E. , TAYLOR JESSICA L. , YU YONGMEI , FLOYD ELIZABETH 
Published: June 2018

Obesity-related insulin resistance is associated with adipose tissue inflammation and visceral adipose tissue expansion via adipocyte hypertrophy and impaired recruitment of new progenitor cells to undergo adipogenesis (hyperplasia). Deletion of the ubiquitin ligase Seven-in-absentia homolog 2 (Siah2) in obese mice significantly reduced adipose tissue inflammation and insulin resistance compared to obese wild type mice. However, larger adipocyte size accompanied this phenotype and subsequent experiments with adipose tissue stromal vascular fraction (SVF) cells showed adipogenesis required Siah2. In an earlier study, we found Siah2 affects adipogenesis by enhancing gene expression of the PPARγ coactivator, Zfp423 via proteasome-dependent degradation of ZFP521, a transcriptional repressor of Zfp423. ZFP423 is an early marker of preadipocyte determination that is expressed in adipocyte progenitor cells. Although Siah2 mediates adipogenesis and is highly expressed in the adipose tissue stromal vascular cell fraction, cell-specific expression of Siah2 in adipose tissue is not well characterized. We found that Siah2 is highly expressed in macrophage. RNA-seq and microarray data from the Immunological Genome Project (Immgen.org) also reported Siah2 expression in lymphocytes. To identify Siah2 expression profile in adipose tissue, unsorted cells and magnetically sorted macrophage, T-cell, B-cell, and SCA-1 positive progenitor cells from mouse adipose tissues SVF were analyzed for Siah2 expression. In parallel, in situ hybridization RNAscope of fat pads was employed to inspect Siah2 mRNA localization in adipose tissue. Since our evidence indicates Siah2 acts upstream of ZFP423, we predict Siah2 is expressed in adipocyte progenitor cells as well as immune cells in adipose tissue. This work will provide the groundwork to better understand how Siah2 controls commitment of progenitor cells to the adipocyte lineage and links obesity to adipose tissue inflammation and insulin resistance.

Disclosure
T. Dang: None. G.E. Kilroy: None. J.L. Taylor: None. Y. Yu: None. E. Floyd: None.
Comprehensive Analysis of the Characteristics and Differences in Adult and Newborn Brown Adipose Tissue
Authors: ZHANG CHUANHAI , YIN RUILI , SHENG YAO , YANG CUI , HE XIAOYUN , XU WENTAO , HUANG KUNLUN 
Published: June 2018

Brown adipose tissue (BAT) plays an important role in maintain body temperature, treating obesity and diabetes. However, the amount and activity of BAT in adults (a-BAT) is very low, while the BAT in infant (i-BAT) is abundant and with strong activation. The a-BAT and i-BAT vary greatly in activation, but the characteristics and differences at the molecular level have not yet been fully revealed. We examined the changes in the mRNA expression of UCP1 and thermogenic genes genes such as PRDM16, PGC1α, CPT1α and CPT1β in a-BAT and i-BAT of mouse. We found that, compared with i-BAT, both UCP1 and thermogenic genes were significantly decreased in a-BAT. Western blot data further confirmed the result. Transmission electron microscope (TEM) and scanning electron microscopy (SEM) also showed a clear distinction in a-BAT and i-BAT. Compared with a-BAT, the lipid droplet is less and mitochondrial density is higher in i-BAT. In addition, the characteristics and differences of a-BAT and i-BAT were comprehensively analyzed by mRNA, microRNA, LncRNA, circRNA, DNA methylation and proteome. Thousands of signifcantly changed lncRNAs and mRNAs as well as proteins were identifed. Compared with i-BAT, we found hyper 383 and hypo 503 DMR related genes in a-BAT by differentially methylated region (DMR) analysis. What’s more, we found 1221 new circRNA in i-BAT and 1991 new circRNA in a-BAT and there were significant higher expression of circRNA in a-BAT compared with i-BAT. Furthermore, we constructed correlated expression networks circRNA-mRNA-lncRNA-methylation with bioinformatics methods. Co-expression analysis showed lnc-NONMMUG024827 and lnc-NONMMUG020075 expression is correlated with Fatty acid metabolism genes, including FASN and ACADA. Taken together, these results provide a better understanding of BAT function and development, and show a novel perspective roles of i-BAT or making a-BAT achieve the better activation and dynamic state just like i-BAT through the epigenetic modification.

Disclosure
C. Zhang: None. R. Yin: None. Y. Sheng: None. C. Yang: None. X. He: None. W. Xu: None. K. Huang: None.
Adipose Tissue Transferrin and Insulin Resistance
Authors: MCCLAIN DON , SHARMA NEERAJ K. , LORENZO FELIPE , JAIN SHALINI , LANGEFELD CARL D. , COMEAU MARY E. , SALAYE LIPIKA , DAS SWAPAN K. 
Published: June 2018

Iron is an important micronutrient involved in several metabolic processes, and excessive iron is a risk factor for insulin resistance (IR) and diabetes. To define the genetic regulation of iron metabolism and its role in IR, we used gene expression, genotype, and insulin sensitivity data from an African American cohort (AAGMEx, N=256). Among the genes in a manually curated list of 62 transcripts representing iron homeostasis genes, expression of 32 in adipose tissue showed significant correlation with SI (p&lt;0.01). The expression levels of transferrin (TF, β= 0.29, p=7.84 x 10-6) and ferritin heavy chain 1 (FTH1, β= -1.2, p=3.75 x 10-13) in adipose tissue were the most positively and negatively associated with SI, respectively. Observations were replicated in independent adipose tissue data sets from individuals of European ancestry (ARCA, N=99; METSIM, N=720). Among these SI-associated transcripts, the strongest cis-regulatory genetic variant (cis-eSNP) was for TF (rs6785596, β= 0.962, p=7.84 x 10-18) in adipose, but not in muscle or liver. To identify the role of TF in adipocytes, we downregulated its expression in a human adipocyte cell model (SGBS). Gene specific shRNA knockdown of TF caused differential expression (log2FC +/-0.4, probability&gt;70%) of 465 genes, involved in mitochondrial function (CPT1B, UCP2), glucose transport (GLUT4), Wnt-pathway/insulin sensitivity (SFRP4, SFRP1), chemokine activity/cell-cell interaction (CXCL1, CXCL12, ICAM1), and genes with possible roles in obesity (CES1, RARRES2). Knockdown of TF mRNA in differentiated SGBS cells impaired mitochondrial respiration (49±10% reduction of maximal oxygen consumption rate) and caused a 34±4% reduction in maximal insulin-stimulated glucose uptake (p&lt;0.05).
In summary, genetic regulation of transferrin expression in adipose tissue plays a novel role in regulating insulin sensitivity.

Disclosure
D. McClain: None. N.K. Sharma: None. F. Lorenzo: None. S. Jain: None. C.D. Langefeld: None. M.E. Comeau: None. L. Salaye: None. S.K. Das: None.
A Positive Allosteric Modulator Enhances the Ability of Beta Cell M3 Muscarinic Receptors to Simulate Insulin Secretion In Vitro and In Vivo
Authors: ZHU LU , WESS JÜRGEN 
Published: June 2018

Several studies have shown that activation of M3 muscarinic acetylcholine (ACh) receptors (M3Rs) expressed by pancreatic beta-cells leads to striking increases in glucose-stimulated insulin release. As a result, we hypothesized that agents that can promote signaling through beta-cell M3Rs might become useful in the treatment of type 2 diabetes. The M3R is a prototypic class A GPCR that is selectively coupled to G proteins of the Gq family. At present, selective M3R agonists that bind to the orthosteric ACh binding site are not available. However, the lab of Craig Lindsley (Bridges et al., 2010) recently described a compound (VU0119498) that binds to an allosteric site on the M3R, thus enhancing ACh-induced signaling through M3Rs. In this study, we tested the ability of this positive allosteric modulator (PAM) to stimulate insulin release in vitro and in vivo. The use of PAMs has the great advantage that it respects the spatio-temporal control of receptor activation, i.e., the PAM is only active upon receptor occupation by an endogenous orthosteric agonist. Studies with cultured MIN6 cells showed that VU0119498 enhanced ACh-induced insulin secretion in an M3R-dependent fashion. In vivo studies demonstrated that PAM treatment of WT mice caused a significant increase in plasma insulin levels, accompanied by a striking improvement in glucose tolerance. These VU0119498 effects were mediated by beta-cell M3Rs since they were absent in mutant mice selectively lacking M3Rs in beta-cells. In future studies, we will use mouse models of diabetes to examine whether this M3R-PAM is endowed with antidiabetic activity. This approach may lead to the development of a novel generation of antidiabetic drugs.

Disclosure
L. Zhu: None. J. Wess: None.
Polymorphic Role of P2Y6 Receptor in Insulin Sensitive Organs—Adipose Tissue and Skeletal Muscle
Authors: JAIN SHANU , WESS JÜRGEN , JACOBSON KENNETH A. 
Published: June 2018

Adipose tissue and skeletal muscle are the two largest insulin-sensitive organs in the body. They play a major role in maintaining whole body glucose and energy homeostasis. Insulin action results in glucose disposal principally in skeletal muscle and to a lesser extent in adipose tissue. Dysregulation of this function promotes the development of obesity, insulin resistance and type 2 diabetes. Many G protein-coupled receptors (GPCRs) are expressed in insulin sensitive organs and thus have emerged as potential targets for novel antidiabetic drugs. P2Y purinergic receptors are a class of GPCRs activated by nucleotides and nucleotide sugars. The purinergic P2Y6 receptor (P2Y6R) is activated by uridine 5’-diphosphate. The potential role of P2Y6R in adipose tissue and skeletal muscle with respect to maintaining whole body glucose homeostasis remains unexplored. To address this issue, we used Cre/loxP technology to generate mice that lack P2Y6R selectively in adipose tissue (AT-Y6-KO) or skeletal muscle (SK-Y6-KO). Interestingly, AT-Y6-KO mice consuming a high fat diet gained less weight, while SK-Y6-KO mice gained more weight than the corresponding control mice. Body composition revealed that the difference in body weight was due to loss or gain in fat mass in AT-Y6-KO and SK-Y6-KO mice, respectively. Improved vs. impaired glucose tolerance and insulin sensitivity was observed in AT-Y6-KO and SK-Y6-KO mice, respectively. Moreover, fasting blood glucose and fed plasma insulin levels were decreased in AT-Y6-KO mice. SK-Y6-KO mice showed elevated blood glucose and plasma insulin levels under both fasting and fed conditions. Detailed mechanistic studies are required for understanding the role of P2Y6R in metabolic tissues and to alter its function for therapeutic purposes.

Disclosure
S. Jain: None. J. Wess: None. K.A. Jacobson: None.
Absence of Changes in Galectin-3 with Insulin Sensitization and Anti-inflammation
Authors: DANDONA PARESH , GHANIM HUSAM , SHAH MANASI S. , GREEN KELLY , MAKDISSI ANTOINE , CHAUDHURI AJAY 
Published: June 2018

Galectin-3 (gal-3) has recently been shown to mediate insulin resistance in mice. Its deletion leads to insulin sensitization while its excess is associated with insulin resistance. We, thus, undertook an investigation into its role in the reversal of insulin resistance in three human models of insulin sensitization: (1) 6 months following bariatric surgery (RYGB) and weight loss in patients with morbid obesity; there was a reduction in BMI from 52.1±4.8 to 40.4±4.0 kg/m2 (p&lt;0.001) and HOMA-IR fell from 7.1±1.1 to 2.1± 0.3 (p&lt;0.001); (2) 12 weeks of pioglitazone (45mg/day) treatment in obese patients with type 2 diabetes, when HOMA-IR fell from 3.5±0.7 to 2.1±0.4; and (3) following 6 months of testosterone replacement in obese patients with type 2 diabetes and hypogonadotropic hypogonadism, when HOMA-IR fell from 4.2±0.9 to 2.7±0.4. Gal-3 levels at baseline were 7.6±1.1, 5.7±0.9 and 4.4±0.7ng/ml, respectively in the 3 groups. In all three models, there was no significant change plasma concentrations of gal-3 (8.0±1.2, 5.9±0.9 and 5.8±0.9ng/ml, respectively) following interventions. There was no change in the expression of gal-3 in peripheral blood mononuclear cells either. Thus, insulin sensitization in all three human models is not associated with any significant alteration in either plasma concentrations or cellular expression of gal-3. Our data do not support a key role for gal-3 in the pathogenesis of insulin resistance or its reversal.

Disclosure
P. Dandona: Advisory Panel; Self; AstraZeneca. Consultant; Self; AstraZeneca. Research Support; Self; AstraZeneca. H. Ghanim: None. M.S. Shah: None. K. Green: None. A. Makdissi: Speaker's Bureau; Self; Eli Lilly and Company. A. Chaudhuri: Speaker's Bureau; Self; AstraZeneca, Eli Lilly and Company, Boehringer Ingelheim Pharmaceuticals, Inc., Merck & Co., Inc., Novo Nordisk Inc..
Mechanism Mediated by S6 Kinase Resulting in both Sufficient Glucose Metabolism Improvement and Insufficient Weight Loss by Glucose Excretion against Fat Load
Authors: KIKUCHI TAKAKO , KUSHIYAMA AKIFUMI , FUJISHIRO MIDORI , SAKODA HIDEYUKI , ASANO TOMOICHIRO , IWAMOTO YASUHIKO 
Published: June 2018

SGLT2 inhibitors have succeeded in improving prognosis in addition to blood glucose control and weight loss in T2D patients, but the reason is unclear, Systemic metabolic changes when improvement by glucose excretion is not sufficiently elucidated. Here, metabolic respiration balance and insulin signal change were analyzed when the high fat diet-induced insulin resistance was improved with the SGLT2 inhibitor tofogliflozin. 8-week-old male C57/Bl6 mice were divided into 3 groups; normal feed group (N group), 60% high fat (HF) feed group and 3 mg/kg/day tofogliflozin (Tofo) administered group on high fat diet. After 8 weeks of food loading, the body weight increased by 30% in the HF group compared to the N group and by 16% in the Tofo. Both IPGTT and IPITT were improved in the Tofo compared with HF group. In the calorimetric analysis, the heat production increased, the respiratory exchange ratio (RER) decreased, and the RER diurnal variation disappeared in the HF group, while the Tofo reduced the energy consumption to the same level as the N group while maintaining the RER equivalent to the HF group. UCP1 in brown fat was elevated in the HF group and improved in the Tofo. In liver, muscle and fat IRS-1 amount decreased in the HF group and revived in Tofo. Phosphorylation of the basal S6K was enhanced in the HF group and disappeared in the Tofo, while after insulin administration, pAkt and resulting pS6K were accelerated in the Tofo.
In conclusion, urinary glucose excretion against high fat load is resulting in improvement of IRS-1 degradation by basal S6Kinase promotes insulin Akt activation. Lipid synthesis is enhanced by insulin while energy expenditure is normalized. Inhibited fat burning compensation leaves weight gain, but since insulin signal has been improved enough, glucose metabolism is improved adequately. This suppression of catabolism might be involved in the improved prognosis by administration of SGLT2 inhibitors.

Disclosure
T. Kikuchi: None. A. Kushiyama: Research Support; Self; Teijin Pharma Limited, Sanwa Kagaku Kenkyusho Co., Ltd., Kowa Pharmaceutical Co., Ltd, StaGen. Consultant; Self; RIZAP. M. Fujishiro: Research Support; Self; Johnson & Johnson Services, Inc.. H. Sakoda: None. T. Asano: Research Support; Self; Teijin Pharma Limited, Sanwa Kagaku Kenkyusho Co., Ltd., Sanofi K.K. Y. Iwamoto: Board Member; Self; Japan Diabetes Foundation.
Impact of Blood Sugar Control on Metabolites and Carbohydrate Metabolism in Type 1 Diabetes
Authors: KUHTREIBER WILLEM , JANES SOPHIE E. , YANG MICHAEL W. , FAUSTMAN DENISE L. 
Published: June 2018

In type 1 diabetes (T1D), long-term blood sugar control measured by HbA1c can vary over a wide range. Although metabolites are commonly studied in type 2 diabetes (T2D) as they relate to HbA1c, similar studies in T1D are few. Since the underlying etiologies of T1D and T2D are different, we explored the overall pathways of metabolism in T1D subjects with tight vs. poor blood sugar control. T1D subjects (n=50) were divided into two groups (n=25 each) based on low vs. high HbA1c (Screen 1, low: mean 6.7 ± 0.1%; high: mean 8.7 ± 0.3%). Serum samples were analyzed on a metabolomic GC/HPLC/MS platform and analyzed for differences in biochemicals between the groups. The screen was repeated with a second group of 50 patients for verification (Screen 2, mean 6.3 ± 0.1%; mean 8.0 ± 0.2%) and then both screens combined. For each detected biochemical, average scaled intensity was determined and statistical significance of differences was calculated using a two-tailed, unpaired Student’s T test (p-values) and False Discovery Rate (q-values). The platform distinguished 690 components in Screen 1 and 623 biochemicals in Screen 2. In Screen 1, two biochemicals, including glucose, showed significant differences (≦0.05) for both p and q value. In Screen 2, none of the biochemicals reached threshold. When the screens were combined (100 samples), 10 biochemicals were significant for both p and q. Three components (glucose, mannose and 1,5-AG) were carbohydrates related to blood sugar control and thus expected in a high and low HbA1c analysis. Significant biochemicals commonly found in T2D and related to blood sugar control were not significant in T1D for both p and q in the screens. We conclude that few metabolites are correlated in T1D with tight vs. poor blood sugar control compared to T2D. Unlike T2D, metabolites related to intracellular sugar utilization, the Krebs cycle and purine synthesis are unrelated to blood sugar control in T1D cohorts.

Disclosure
W. Kuhtreiber: None. S.E. Janes: None. M.W. Yang: None. D.L. Faustman: None.
Preserved Beta-Cell Function during Acute DKA in Ketosis-Prone Diabetes
Authors: MEHTA PARAS B. , MULUKUTLA SURYA N. , HSU JEAN W. , KEENE KELLY R. , RAM NALINI , BALASUBRAMANYAM ASHOK 
Published: June 2018

Introduction: Ketosis prone diabetes (KPD) comprises heterogeneous syndromes characterized by presentation with DKA. “ß+” subgroups of KPD have substantial beta cell functional reserve measured ≥ 1 month after the index DKA episode, and can discontinue insulin therapy. Either acute beta cell dysfunction leading to DKA is reversible in these patients, or DKA is due to factors other than severe beta cell dysfunction. In a longitudinal study, we measured serum C-peptide, insulin and counter-regulatory hormones in patients with hyperglycemic crises upon admission to the emergency department (ED) to determine beta cell function during the acute DKA episode.
Methods: Among 57 adult patients assessed so far, 32 had DKA (anion-gap acidosis with elevated beta-hydroxybutyrate) and 25 had non-ketotic hyperglycemia. Blood was sampled prior to insulin administration in 24 patients (50% with DKA), and ≤9 h after starting the insulin infusion in 33.
Results: There was no significant difference in C-peptide, glucose, insulin, or cortisol levels in DKA vs. non-ketotic hyperglycemia groups. Mean C-peptide was 1.4 ± 0.5 ng/mL in the DKA group and 2.1 ± 0.4 ng/mL in the non-DKA group (p = 0.29). Among the 24 patients whose blood was sampled prior to administering insulin, there was no group difference in C-peptide levels (2.3 ± 1.2 vs. 2.6 ± 0.7 ng/mL, p = 0.83). C-peptide was &gt;1.5 ng/mL in 22% of the DKA group.
Conclusions: Many adults with KPD have substantial beta cell function at the time of the index DKA episode, a finding that defies the concept that near-complete absence of endogenous insulin secretion is required to develop DKA. Longitudinal follow-up testing will determine whether these patients populate KPD subgroups that are formally defined as “ß+”; such an outcome would indicate that their proclivity to develop ketoacidosis may be due to factors other than absence of endogenous insulin, such as defective amino acid metabolism (Patel et al, Diabetes 62:912-922, 2013) or dysregulation of counter-regulatory hormones.

Disclosure
P.B. Mehta: None. S.N. Mulukutla: None. J.W. Hsu: None. K.R. Keene: None. N. Ram: None. A. Balasubramanyam: None.
MEDI0382, a GLP-1/Glucagon Receptor Dual Agonist, Shows Differential Brain Activation vs. Liraglutide in Mice
Authors: BURKE LUKE K. , BROWN LEE , LAPOINTE JEAN-MARTIN , SULIKOWSKI MICHAL GRZEGORZ , LEWIS ARTHUR R. , TREVASKIS JAMES , BAKER DAVID 
Published: June 2018

MEDI0382 is under development for the treatment of type 2 diabetes. MEDI0382 reduces food intake and body weight in obese mice and primates. In rodents, the weight-reducing effects of MEDI0382 are superior to those of the GLP-1 analogue, liraglutide. The current study characterised the activation of distinct neuroanatomical areas following peripheral administration of MEDI0382, relative to liraglutide and the glucagon receptor agonist, G1432. C57Blk6 mice were fasted for 4 h and then injected with a single dose (3 nmol/kg; s.c) of test agent or vehicle (n=4 each). After 2 h, mice were sacrificed and brains were dissected out and immersion-fixed in formalin (24-48 h). The brains were then cut into 3 mm serial slices and processed to paraffin blocks. Each block was sectioned entirely, sampling a 4µm step section every 100µm. Each section was immunohistochemically stained for c-fos, using a rabbit anti-fos polyclonal, with haematoxylin counterstain. Stained sections were digitally scanned at 20x magnification (Aperio AT2). The appropriate brain sections containing the area postrema (AP), the nucleus of the solitary tract (NTS), and the hypothalamic parabrachial (PBN) and arcuate nuclei were selected. These areas were manually delimited using the online Allen mouse brain atlas. The number of positive and negative nuclei were automatically counted (Halo), and reported as % of total positive cells and number of cells per tissue area. MEDI0382 significantly increased c-fos activation in the AP and NTS vs. vehicle, whereas liraglutide and G1432 showed no difference from vehicle. There was no significant increase in c-fos activation in the arcuate nucleus or PBN in any treatment group when compared to vehicle.
In summary, the neuronal activation by MEDI0382 shows that distinct differences were observed compared to GLP-1 and glucagon agonists alone, suggesting that a different pattern of activation exists for the dual agonist, MEDI0382 vs. the monotherapies.

Disclosure
L.K. Burke: None. L. Brown: Stock/Shareholder; Self; AstraZeneca. J. Lapointe: Employee; Self; MedImmune. M. Sulikowski: None. A.R. Lewis: Employee; Self; MedImmune. Stock/Shareholder; Self; MedImmune. J. Trevaskis: Employee; Self; MedImmune. Stock/Shareholder; Self; AstraZeneca. D. Baker: Stock/Shareholder; Self; AstraZeneca.