bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hybrid Insulin Peptides Form in Islets of Nondiabetes Prone Mice
Authors: WILES TIMOTHY , HASKINS KATHRYN M. , DELONG THOMAS 
Published: June 2018

Using a proteomic strategy, we recently identified a new class of post-translational protein modification that occurs in pancreatic beta cells. This modification is a result of insulin fragments that become covalently linked to other protein fragments that form in beta cells. The resulting hybrid insulin peptides (HIPs) contain non-germline encoded amino acid sequences and provide a plausible explanation on how tolerance to self-antigens may be lost leading to the development of type 1 diabetes (T1D). We demonstrated that autoreactive CD4 T cells, isolated from the residual islets of T1D organ donors, target various HIPs. Additionally, diabetes triggering CD4 T cells from non-obese diabetic (NOD) mice, a major animal model for T1D, were shown to be HIP reactive. Using mass spectrometric analyses on cell extracts of beta cell tumors, isolated from NOD-RIPTAg mice, we confirmed the presence of HIPs in those cells. Key questions that arise from these observations are whether HIP formation is a process that takes place in human beta cells, and whether individuals that do not develop diabetes also form HIPs. BALB/c mice do not develop spontaneous diabetes and here we analyzed pancreatic islets from these mice by mass spectrometry. We verified the presence of various HIPs in those islets. Data indicate that the quantity of HIPs formed in NOD islets is equivalent to the quantity formed in BALB/c islets. However, additional quantification steps will be required to validate these observations. It is difficult to obtain sufficient amounts of residual islets from T1D organ donors that allow a detailed proteomic analysis, but our findings now set the stage to look at more accessible islets of non-T1D organ donors to verify the formation of HIPs in humans.

Disclosure
T. Wiles: None. K.M. Haskins: None. T. Delong: None.
Investigating the Role of CD137 Ligand in the Pathogenesis of Type 1 Diabetes
Authors: FODA BARDEES , FORSBERG MATTHEW H. , CIECKO ASHLEY E. , MUELLER KEVIN W. , GEURTS ARON , CHEN YI-GUANG 
Published: June 2018

Pathogenesis of type 1 diabetes (T1D) involves various interactions between genetic and environmental factors. The gene encoding the co-stimulatory molecule CD137 is located within the Idd9.3 T1D susceptibility locus and contributes to diabetes progression in NOD mice. We have previously shown that CD137 expression in T cells has dual functions: CD4+CD137+ T cells negatively regulate T1D development while CD8+CD137+ T cells showed potent diabetogenecity. The protective function of CD137 in CD4+ T cells is likely due to the significant amounts of soluble CD137 (CD137) produced by Foxp3+ Tregs. The interaction between CD137 and its ligand (CD137L) induces two signaling pathways, forward one driven by CD137 and the reverse signaling mediated by CD137L, both of which modulate T cell function. Here, we study the impact of CD137L deficiency on T1D to gain further insight into disease pathogenesis. We successfully generated a mouse strain with the NOD background and knockout of the gene encoding CD137L (Tnfsf9) using CRISPR/Cas9 technology. Relative to wild type NOD, Tnfsf9-/- mice showed significant delay in T1D development, less islet-infiltrating autoreactive CD8 T cells, reduced high-avidity IGRP autoreactive CD8 T cells in the spleen and pancreatic lymph node, and less inflamed islets. Interestingly, we detect significant increase in serum levels of sCD137. Furthermore, we could not detect differences in CD137+ Treg populations between NOD and Tnfsf9-/- mice. In bone marrow transfer experiments, CD137L deficiency in either hosts or donors was able to suppress T1D development. Tnfsf9-/- and wild type T cells showed similar capacity to induce T1D in NOD.Rag1-/- recipients. We are working on identifying the cellular source of increased sCD137 and the mechanism behind this elevation. We direct our efforts to understand how CD137-CD137L interaction can modulate T1D pathogenesis and how to translate the data from NOD mouse to understand the pathogenesis of human diabetes.

Disclosure
B. Foda: None. M.H. Forsberg: None. A.E. Ciecko: None. K.W. Mueller: None. A. Geurts: None. Y. Chen: None.
Acceptance of Murine Islet Allografts without Immunosuppression in the Inguinal Subcutaneous White Adipose Tissue Pretreated with bFGF
Authors: NAKAFUSA YUKI , NITTA NAOYOSHI , NAKAMURA MASAFUNI , YASUNAMI YOHICHI 
Published: June 2018

Prevention of immune rejection without immunosuppression is a goal for transplant immunology. Previous report demonstrated that rejection of rat islet allografts in sc space of the back between low responder strains was prevented by pretreatment of the site with bFGF (AJT2014). However, it was not in the high responder combination of mice (BALB/c to C57BL/6). Here, we determined whether islet allografts in the inguinal subcutaneous white adipose tissue (ISWAT), a novel site of islet transplantation (tx), pretreated with bFGF are accepted without immunosuppression in mice. An agarose rod containing bFGF was buried in the ISWAT of a C57BL/6 mouse, and 1-3 weeks later 400 BALB/c islets (2 donors) were grafted in the space after the removal of a rod. Recipients were made diabetic by STZ (180mg/kg, iv) at 3 days prior to tx. Eventually, we found that 10μg bFGF/50μl/rod with 2 week interval is the optimal, in which 11/14 recipient mice remained normoglycemic (&lt;200mg/dl) for more than 60 days. Removal of the ISWAT with islets promptly made recipient mice hyperglycemic again. Histologically, intact islets were seen in the ISWAT. In contrast, islet allografts (n=7) in the ISWAT pretreated with vehicle were rejected by 10 days. FACS revealed an expansion of CD8 T cells in the ISWAT rejecting but not accepting islet allografts. In the latter, IL-10+cells including Gr-1+ cells were seen. Re-tx of BALB/c islets (n=3) to the contralateral ISWAT of normoglycemic mice induced rejection of the initial BALB/c grafts and made recipient mice hyperglycemic again, while that of C3H (n=3) did not. These findings indicate that acceptance of murine islet allografts without immunosuppression was achieved when the ISWAT pretreated with bFGF was the site and that the acceptance appeared mediated by local rather than systemic unresponsiveness.

Disclosure
Y. Nakafusa: None. N. Nitta: None. M. Nakamura: None. Y. Yasunami: None.
Maintenance of ß-Cell Heterogeneity Is Required for Normal Islet Function
Authors: NASTESKA DANIELA , RUTTER GUY A. , ZHOU QIAO , HODSON DAVID 
Published: June 2018

Aim: Recent studies have shown the existence of discrete β-cell subpopulations with differing levels of maturity and function. We sought here to understand how this diversity may influence islet function and insulin secretion using a ‘loss of heterogeneity‘ model.
Material and Methods: Overexpression was achieved using an adenoviral polycistronic construct for Pdx1, MafA, Ngn3 and mCherry (Ad3-NPM). Pdx1 was silenced using short hairpin RNAs (shRNA). Gene and protein levels were detected by qPCR and immunohistochemistry (IHC), respectively. Ca2+ fluxes, ATP/ADP ratios and cAMP levels were analysed using dyes/biosensors and high-speed spinning disk microscopy. Glucose- (GSIS) and incretin-stimulated insulin secretion (ISIS) were measured using HTRF assays.
Results: Ad3-NPM increased Pdx1 (12-fold vs. CT; P&lt;0.01) and MafA levels (2-fold vs. CT) without affecting Ngn3. IHC showed that Pdx1 overexpression occurred predominantly in Pdx1low β-cells, forcing higher uniformity throughout the β-cell complement. The α/β-cell ratio did not change, indicating absence of transdifferentiation. Ca2+ responses to glucose were markedly blunted (ΔF=0.81 vs. 0.44 AU, CT vs. Ad3-NPM; P&lt;0.01), and this was accompanied by a decrease in β-cell-β-cell cell connectivity and hub number (12.6 vs. 5.6 % hubs, CT vs. Ad3-NPM; P&lt;0.05), the latter previously shown to be relatively immature cells with pacemaker features. ATP/ADP ratios and cAMP levels were unaffected. Glucose- and incretin-stimulated insulin secretion was impaired (% content secreted = 8.7 vs. 5.2 for GSIS and 56.4 vs. 29.02 for ISIS, CT vs. Ad3-NPM; both P&lt;0.01). Similar results for Ca2+ dynamics, cellular connectivity and insulin secretion were obtained in islets treated with Pdx1 shRNA to increase the size of the Pdx1low population.
Conclusion: Loss of β-cell heterogeneity, whether due to increased or decreased maturity, leads to islet failure and impaired insulin secretion. Thus, cellular diversity appears necessary for normal islet function.

Disclosure
D. Nasteska: None. G.A. Rutter: Research Support; Self; Servier. Q. Zhou: None. D. Hodson: None.
Circulating ANGPTL8 and ANGPTL4 Levels Are Increased in Patients with Hyperglycemia Combined Dyslipidemia
Authors: YU XUEFENG , LU PUHAN , CHEN XI 
Published: June 2018

Context: Angiopoietin-like protein 8 (ANGPTL8) and Angiopoietin-like protein 4 (ANGPTL4) are regarded as protein regulating triglyceride (TG) metabolism in mice. However, whether ANGPTL8/4 are involved in glucose and/or lipid metabolism in human remain unclear.
Objective: To examine circulating ANGPTL8/4 levels in subjects with hyperglycemia and/or dyslipidemia and their correlation with glucose and lipid metabolism. Design, Setting and Participants: Serum ANGPTL8/4 levels were measured using ELISA in age-, sex-, and BMI- matched healthy control subjects (CON) (n=92), subjects with isolated hyperglycemia (IHG) (n=87), with isolated dyslipidemia (IDL)(n=86) and hyperglycemia combined dyslipidemia (HCD)(n=99) from the Risk Evaluation of cAncers in Chinese diabeTic Individuals: a lONgitudinal (REACTION) study.
Results: Serum ANGPTL8 and ANGPTL4 levels were both elevated in patients with HCD compared to CON subjects. After controlling for age, sex and blood lipid, ANGPTL8 levels positively correlated with fasting plasma glucose (FPG) (partial r = 0.154), HbA1c (partial r = 0.110) and triglycerides and glucose (TyG) index (age, sex adjusted)(partial r = 0.224). After controlling for age, sex and FPG, ANGPTL8 levels positively correlated with TG (r = 0.163), TG/HDL (r = 0.147) and non-HDL/HDL (r = 0.134). ANGPTL4 were positively correlated with FPG, 2h-glucose, HbA1c and TyG index. Among lipid-related variables, ANGPTL4 were positively correlated with TG, TG/HDL, non-HDL/HDL and negatively correlated with HDL-cholesterol. After controlling for related variables, the correlations were the same.
Conclusion: Circulating ANGPTL8 and ANGPTL4 levels were increased in patients with HCD and might play an important role in linking glucose and lipid metabolism.

Disclosure
X. Yu: None. P. Lu: None. X. Chen: None.
Hypertriglyceridemia per se Is Not an Independent Risk Factor for Beta-Cell Dysfunction
Authors: YAMAUCHI JUN , ZHANG TING , LEE SOJIN , DONG HENRY 
Published: June 2018

Hypertriglyceridemia results from increased production and decreased clearance of triglyceride-rich very low-density lipoproteins, a pathological condition that accounts for heightened risk of ischemic vascular diseases in obesity and type 2 diabetes. Despite its intimate association with insulin resistance, whether hypertriglyceridemia constitutes an independent risk for beta-cell dysfunction in diabetes is unknown. Answering this fundamental question is stymied by the fact that hypertriglyceridemia is intertwined with hyperglycemia and insulin resistance in obese and diabetic subjects. To circumvent this limitation, we took advantage of apolipoprotein C3 (ApoC3)-transgenic mice, a model with genetic predisposition to hypertriglyceridemia without alterations in glucose metabolism. We showed that ApoC3-transgenic mice, as opposed to age/sex matched wild type littermates, develop hypertriglyceridemia with concomitant elevations in plasma cholesterol and non-esterified fatty acid levels. Anti-insulin and anti-glucagon dual immunohistochemistry in combination with morphometric analysis revealed that ApoC3-transgenic and wild type littermates had similar beta-cell and alpha-cell masses as well as islet size and architecture. These effects correlated with similar amplitudes of glucose-stimulated insulin secretion and similar degrees of postprandial glucose excursion in ApoC3-transgenic vs. wild type littermates. ApoC3-transgenic mice did not visualize lipid infiltration into islets, correlating with the lack of ectopic triglyceride and cholesterol depositions in the pancreata. ApoC3-transgenic mice, despite persistent hypertriglyceridemia, maintained euglycemia under both fed and fasting conditions without manifestation of insulin resistance and fasting hyperinsulinemia. We concluded that hypertriglyceridemia per se is not an independent risk factor for beta-cell dysfunction.

Disclosure
J. Yamauchi: None. T. Zhang: None. S. Lee: None. H. Dong: None.
Effect of a New Type of Nanomaterial on Glucose and Lipid Metabolism
Authors: WU JIN , CHEN YINGBO , LIU LIPING , YAO QING , LIU XIAOCEN , WU YINGJIE 
Published: June 2018

Diabetes mellitus is a systemic metabolic disease characterized by disrupted glucose and lipid metabolism. With an alarming rise of incidence each year, there is therefore a pressing need to find more efficient medicines and methods for its treatment. Using the obese type 2 diabetes db/db mouse model, in our pervious work we found that a new type of nanomaterial could inhibit the formation of insulin resistance. The underlying mechanisms of its therapeutic effect in the glucose and lipid metabolism are further investigated in the present study. Compared with the control mice, the blood glucose of the mice decreased significantly after the nanomaterial injection, accompanied by a dose-dependent hypoglycemic effect. The impaired glucose tolerance and insulin resistance were significantly improved in mice treated with the material. We found that the expression of PCK1 and G6Pc were reduced at both RNA and protein levels, whilst p-AKT was stimulated at the protein level after the nanomaterial injection, which indicated its positive impact on glucose metabolism. Reductions in total, adipose and liver weight were also present in db/db mice treated with the material, compared with the control. In the aspect of lipid metabolism, H and E and oil red O staining of liver tissue revealed an amelioration of fatty liver symptoms in mice injected with the material. Consistent with the observed phenotype, the mRNA expression of the FA synthesis enzymes ACC and FAS were decreased significantly after the treatment, as confirmed by q-PCR analysis. Meanwhile, an observably lower nucleus abundance of SREBP1c, the important transcriptional regulator of ACC and FAS, was detected following the treatment, using immunohistochemical approach. These results demonstrate the striking effects of the nanomaterial on the glucose and lipid metabolism. Taken together, our data implies the significance of this novel type of nanomaterial as the next-generation therapy for diabetes and fatty liver, yet the relevant mechanisms are to be further examined.

Disclosure
J. Wu: None. Y. Chen: None. L. Liu: None. Q. Yao: None. X. Liu: None. Y. Wu: None.
Serum Uric Acid (SUA), Urinary Albumin Excretion (UAE), and Hypertension (HTN) in Adolescents with Type 2 Diabetes (T2D) in the TODAY Study
Authors: BJORNSTAD PETTER , LAFFEL LORI M. , LYNCH JANE L. , GHORMLI LAURE EL , WEINSTOCK RUTH S. , TOLLEFSEN SHERIDA E. , NADEAU KRISTEN J. 
Published: June 2018

Elevated SUA is increasingly recognized as a risk factor for kidney disease in adults with diabetes, yet there are limited data in youth. We hypothesized that elevated SUA would predict development of elevated UAE and HTN over time in teens with T2D. Serum creatinine, cystatin C, SUA, and urine albumin to creatinine ratio (ACR) were assessed in 539 youth, ages 12-17 with T2D duration &lt;2 years at baseline in the TODAY study. Estimated GFR (eGFR) was calculated using creatinine and cystatin C. HTN was defined as systolic (SBP) or diastolic blood pressure (DBP) ≥130/80 mm Hg and elevated albumin excretion (UAE) as ACR ≥30mg/g. Mean arterial pressure (MAP) was calculated ([SBP + 2 (DBP)]/3). Generalized estimating equations and Cox proportional hazard models evaluated the relationship between SUA and outcome variables longitudinally over 7 years, adjusting for age, sex, race/ethnicity, BMI, A1c, eGFR, ACEi/ARB use, and TODAY treatment group assignment. Hyperuricemia (≥6.8 mg/dL) was present in 25.6%, HTN in 18.7%, and elevated UAE in 6.1% at baseline, and boys had higher baseline SUA than girls (6.7±1.4 vs. 5.4±1.2 mg/dl, p&lt;0.0001). Over 7 years, 37.4% developed HTN and 18.0% elevated UAE. Baseline SUA correlated with increase in SBP (β±SE: 0.66±0.16, p&lt;.0001), DBP (0.37±0.15, p=0.01), MAP (0.47±0.14, p=0.001), and log UAE (0.05±0.02, p=0.01) over time in multivariable models. Higher baseline SUA increased risk of incident HTN (HR: 1.20, 95% CI 1.05-1.36, p=0.007, per 1 mg/dL increase in SUA) and incident elevated UAE (HR: 1.23, 95% CI 1.03-1.47, p=0.02, per 1 mg/dL increase in SUA) in fully adjusted models. Hyperuricemia was common in youth with T2D; higher baseline SUA independently increased risk for onset of HTN and elevated UAE over 7 years. Therapies lowering SUA may hold promise to impede development of diabetic kidney disease and HTN in T2D youth.

Disclosure
P. Bjornstad: Consultant; Self; Boehringer Ingelheim GmbH. L.M. Laffel: Consultant; Self; Eli Lilly and Company, Novo Nordisk Inc., Sanofi US, MannKind Corporation, Roche Diagnostics Corporation, Dexcom, Inc., Insulet Corporation, AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Johnson & Johnson Diabetes Institute, LLC. J.L. Lynch: Other Relationship; Self; Novo Nordisk Inc.. Research Support; Self; Daiichi Sankyo Company, Limited. L. El Ghormli: None. R.S. Weinstock: Research Support; Self; Medtronic MiniMed, Inc., Mylan, Kowa Pharmaceuticals America, Inc., Diasome Pharmaceuticals, Inc., Calibra Medical, Dexcom, Inc., Ultradian Diagnostics LLC., JAEB Center For Health Research, JDRF, National Institute of Diabetes and Digestive and Kidney Diseases. S.E. Tollefsen: None. K.J. Nadeau: None.
The TCF7L2 Variant rs7903146 Affects the Risk of Youth-Onset Type 2 Diabetes by Reducing the Incretin Effect on Insulin Secretion
Authors: GALDERISI ALFONSO , PIERPONT BRIDGET , D'ALESSIO DAVID , SANTORO NICOLA , CAPRIO SONIA 
Published: June 2018

Background: Common variants of the transcription factor-7-like-2 gene (TCF7L2) have been implicated in the progression of prediabetes to T2D. We explored the effect of the rs7903146 variant on the incretin effect in youths with dysglycemia.
Methods: 5 carriers with the risk-genotype of TCF7L2 (TT at the rs7903146, 14.4±2.3y, BMI 34.7±6.4kg/m2) and 5 with the wild type genotype CC (16.2±1.9y, BMI 36.8±6.0kg/m2) underwent a 3-hour OGTT followed, a week later, by an isoglycemic intravenous glucose infusion (IVGTT), designed to match the plasma glucose concentrations during the OGTT. The incretin effect was measured as 100*(SROGTT-SRIVGTT)/SROGTT where SR was the secretion rate of c-peptide.
Results: As shown in the Figure, the plasma glucose profile in the OGTT and IVGTT were well matched in both groups. The increase in SR during the OGTT compared to IVGTT was significantly lower in the carriers of the TT compared to CC genotype (ΔiAUCc-peptide 1281±688.6 vs. 5632±1604 pmol/L*min, p &lt; 0.025). Thus, relative to the control group, carriers of the TT-risk genotype had a significant reduction of the incretin effect (TT 0% [-11.74, 16.84], CC: +35% [12.05, 55.71]; p &lt;0.018).
Conclusion: The TCF7L2 variant rs7903146 impairs the incretin effect in obese youths carrying the risk-genotype (TT), suggesting a causative mechanism for the association of this variant with progression to T2D.

Disclosure
A. Galderisi: None. B. Pierpont: None. D. D'Alessio: Consultant; Self; Intarcia Therapeutics, Inc., Eli Lilly and Company, Merck & Co., Inc., Novo Nordisk A/S. N. Santoro: None. S. Caprio: None.
Risk Factors of Youth Type 2 Diabetes (Y-T2DM) and Prevalence of Dysglycemia (DG)
Authors: SALEH MOHAMED , KIM JOON YOUNG , MARCH CHRISTINE , YOUSUF SHAHWAR , ARSLANIAN SILVA A. 
Published: June 2018

The incidence of Y-T2DM is increasing parallel with the childhood obesity epidemic. The ADA consensus recommends screening for Y-T2DM or prediabetes in asymptomatic overweight youth who have any two additional risk factors (RFs): family history of T2DM in 1st or 2nd degree relatives, minority race/ethnicity, insulin resistance [acanthosis nigricans, polycystic ovary syndrome, hypertension, dyslipidemia, and small for gestational age], and maternal GDM during the child’s gestation. However, the evidence for these recommendations is minimal, if not nonexistent. In an established pediatric obesity registry, OGTT data of 618 youth ˃10 years old, BMI ≥ 85th%, were analyzed to evaluate the prevalence of DG based on the frequency of RFs. Participants were divided into 4 groups according to the number of RFs. Participants were 70% females, 70% Caucasians, 31% with prediabetes, and 5.1% with Y-T2DM. With increasing RFs, the prevalence of normal glucose tolerance (NGT) declined, DG increased, fasting glucose concentration did not change, but fasting insulin concentration increased significantly (Table: mean ± SE). Participants with 1 RF had ∼25% prevalence of DG. The odds for DG with 2, 3 and ≥ 4RFs were 1.6, 1.7, and 2.5 respectively compared to 1 RF (P=0.01).
In conclusion, the prevalence of prediabetes and T2DM in overweight/obese youth is high ∼25% in the presence of only 1 RF, and escalates with increasing number of RFs.
Obesity + 1 RF (n=45)Obesity + 2 RF (n=165)Obesity + 3 RF (n=223)Obesity + ≥4RF (n=185)P-ANOVAAge (years)13.7 ± 0.314.0 ± 0.214.3 ± 0.114.4 ± 0.2NSGlycemic status (NGT/Dysglycemia), n (%)34 (75.6 %) / 11 (24.4 %)1(65.5 %) / 57 (34.5 %)143 (64.1 %) / 80 (35.9 %)103 (55.7 %) / 82 (44.3 %)0.009BMI percentile97.6 ± 0.498.0 ± 0.398.4 ± 0.298.6 ± 0.2NSFasting glucose (mg/dl)92.4 ± 1.293.9 ± 0.994.0 ± 0.994.9 ± 1.2NSFasting insulin (μu/ml)25.6 ± 2.331.0 ± 1.934.7 ± 1.642.5 ± 2.7&lt; 0.0001OGTT 2-hr. Glucose (mg/dl)117.6 ± 4.7125.9 ± 3.0129.4 ± 2.7138.4 ± 3.30.001OGTT 2-hr. Insulin (μU/ml)121.5 ± 17.6160.7 ± 11.2169.9 ± 10.8217.0 ± 14.3&lt; 0.0001

Disclosure
M. Saleh: None. J. Kim: None. C. March: None. S. Yousuf: None. S.A. Arslanian: None.