bluuebunny/crossref_metadata_2025_split huggingface dataset:
Longevity of Beta Cells and Protein Complexes Revealed by Isotope Imaging
Authors: E DRIGO RAFAEL ARROJO , TOYAMA BRANDON H. , TYAGI SWATI , LEV-RAM VARDA , DEERINCK THOMAS J.J. , BUSHONG ERIC A. , RAMACHANDRA RANJAN , LECHENE CLAUDE , ELLISMAN MARK H. , HETZER MARTIN 
Published: June 2018

We discovered recently that long-lived cells (LLCs), such as neurons, contain long-lived proteins (LLPs) in the nucleus that can last a lifetime, and their decline during aging impairs nuclear function. Beta cells are LLCs with a slow cell replication process, yet it is unknown whether individual beta cells have different lifespans. We tested this hypothesis by using a hybrid microscopy and mapping platform (MIMS-EM) to identify beta cells and quantify cell and protein turnover in the islets of Langerhans. This is achieved by pulse-labelling mice with an 15N-rich diet followed by a chase period with a control 14N-rich diet for up to 2 years. Here, old cells and protein structures retain 15N while those that turnover incorporate 14N. The levels of 15N and 14N were measured with multi-isotope mass spectroscopy (MIMS) and the 15N-to-14N ratio reports on cell and protein turnover. Importantly, the MIMS data is correlated with scanning electron microscopy (EM) to create high-resolution maps of cells and intra-cellular structures overlaid with age information. Here we report the use of MIMS-EM on mouse islets to discover that beta cells have vastly different ages. In fact, while approximately 75% of beta cells replicate between 2-4 times, almost 25% of all beta cells does not replicate at all after weaning and remain quiescent for an entire lifetime, and therefore, are as old as cortical neurons. Such longevity was also found in other islet cell-types and at the protein super-complex level, where 15N accumulation on the primary cilium of beta cells strongly indicates that this important signaling structure is exceptionally long-lived. Strikingly, and similar to what is found in old rat neurons, beta cells from humans aged &gt;60-years-old lose specific nuclear LLPs and show signs of impaired nuclear function. Together, our data shows that beta cell longevity is heterogeneous and identifies the loss of nuclear LLPs in human beta cells as a potential contributing factor to age-dependent loss of beta cell function.

Disclosure
R. Arrojo e Drigo: Stock/Shareholder; Self; VTV Therapeutics, Novo Nordisk A/S. B.H. Toyama: None. S. Tyagi: None. V. Lev-Ram: None. T.J.J. Deerinck: None. E.A. Bushong: None. R. Ramachandra: None. C. Lechene: None. M.H. Ellisman: None. M. Hetzer: None.
Socioeconomic Profiles as Predictors of Glycemic Control in Youth with Type 1 Diabetes
Authors: SUTHERLAND MELANIE W. , MA XIAONAN , MENDOZA JASON A. , BELL BETHANY A. , REBOUSSIN BETH A. , KAHKOSKA ANNA R. , SAUDER KATHERINE A. , PIHOKER CATHERINE , LIESE ANGELA D. 
Published: June 2018

Various measures of socioeconomic status (SES) predict glycemic control in youth and young adults (YYA) with type 1 diabetes; however, rarely have multiple SES factors been considered simultaneously, including parental education and income, food security, health insurance status, and food assistance. The purpose of this study was to identify multidimensional SES profiles in YYA with type 1 diabetes and to assess the association between these profiles and glycemic control. Data from 257 YYA with type 1 diabetes enrolled in the SEARCH Food Insecurity Ancillary Study in South Carolina and Washington between the years 2013 and 2015 were included. We identified SES profiles utilizing latent class analysis and used multivariable logistic regression to compare the profiles’ glycemic control, with HbA1c &gt; 9% defined as poor glycemic control. Two profiles were identified: Profile 1 (74%) included YYA that were of higher parental income and education, and less likely to have government-funded health insurance, to receive food assistance, and to be food insecure. Profile 2 (26%) included YYA who were categorized opposite to that of profile 1. In profile 2, 60% of YYA had poor glycemic control compared to 44% of YYA in profile 1. After adjustment for age, sex, race/ethnicity, site, diabetes duration, and diabetes medication, YYA in profile 2 were significantly more likely to have poor glycemic control relative to YYA in profile 1 (OR = 1.94, 95% CI = 1.01-3.71). Membership to a lower SES profile is associated with poor glycemic control among YYA with T1D. Strategies to improve glycemic control, particularly in YYA who belong to lower SES profiles, are needed.

Disclosure
M.W. Sutherland: None. X. Ma: None. J.A. Mendoza: None. B.A. Bell: None. B.A. Reboussin: None. A.R. Kahkoska: None. K.A. Sauder: None. C. Pihoker: None. A.D. Liese: None.
Saturated Fatty Acids Impair Organellar Trafficking in Dorsal Root Ganglion (DRG) Sensory Neurons
Authors: LOGRASSO GIOVANNI , RUMORA AMY , HAIDAR JULIA A. , LENTZ STEPHEN I. , FELDMAN EVA L. 
Published: June 2018

Diabetic neuropathy (DN) is a highly prevalent complication of type 2 diabetes that is associated with dyslipidemia and causes length-dependent sensory nerve damage in the lower extremities. The primary sensory neurons, dorsal root ganglion (DRG) neurons, extend bundles of axons into the peripheral nerves and transmit sensory information from the limbs. These neurons require a constant supply of mitochondrial derived energy maintained by trafficking of the mitochondria throughout the length of the DRG axon. We have shown that dyslipidemia-associated saturated fatty acid (FA) palmitate impairs mitochondrial trafficking whereas unsaturated FA oleate prevents this impairment. In the current study, we assessed whether FAs alter trafficking of synaptic vesicles in DRG axons to determine whether palmitate impairs mitochondrial trafficking specifically or global organellar transport. Primary DRG neurons were treated with physiological concentrations of FAs ranging from 31.25-250 µM saturated FA palmitate, unsaturated FA oleate, and oleate/palmitate mixtures. Mitochondria and synaptic vesicles showed a significant dose-dependent reduction in motility with increasing concentrations of saturated FA palmitate. However, mitochondria and synaptic vesicles retained motility with treatments of unsaturated FA oleate compared to the controls. Similarly, palmitate induced a trending decrease in velocity of bi-directional motile mitochondria and synaptic vesicles, whereas oleate treatments did not alter mitochondrial and synaptic vesicle velocity. Finally, co-incubation of oleate prevents palmitate-induced inhibition of mitochondrial and synaptic vesicle trafficking. These results suggest that high concentrations of saturated FAs lead to the dysfunction of global organellar transport throughout the DRG axon associated with the development and progression of DN.

Disclosure
G. LoGrasso: None. A. Rumora: None. J.A. Haidar: None. S.I. Lentz: None. E.L. Feldman: None.
Dextrose-Sulfonylurea Challenge as a Screening Test for Monogenic Diabetes in Patients Diagnosed with Type 1 Diabetes
Authors: WOOD AURELIA C.H. , REMEDI MARIA S. , NICHOLS COLIN , MARSHALL BESS A. 
Published: June 2018

Monogenic diabetes due to ABCC8, KCNJ11, HNF1A and HNF4 can be treated with sulfonylurea (SU). The SEARCH for Diabetes in Youth confirmed most patients with monogenic diabetes are misdiagnosed with T1DM, and that family history and fasting C-peptide do not reliably increase pre-test probability for diagnosis. Confirmatory genetic testing is expensive and methods to improve cost-benefit ratio do not exist. As such, we developed a dextrose-SU challenge to assess C-peptide response to SU as indication of clinically significant underlying β-cell excitation defects. We postulate negative response to hyperglycemia with positive response to SU indicates presence of a genetic defect in glucose-stimulated insulin secretion. This challenge has been completed on 42 subjects with TIDM on insulin therapy. Blood glucose (BG) and C-peptide were obtained at regular intervals prior to and after a 0.5 g/kg IV dextrose bolus, a single dose of glipizide was given 20 minutes after dextrose (0.3 mg/kg max 15mg if &lt;50 kg; 40 mg if &gt;50 kg) and BG and C-peptide were obtained until study completion. Twenty of the 42 subjects had undetectable C-peptide. Twenty-two subjects had detectable C-peptide, 13 of which showed preferential C-peptide response to glipizide (ΔC-peptide 0.41 ± 0.45 ng/mL) compared to hyperglycemia (Δ 0.05 ± 0.03 ng/mL). This suggests islets may show modest but specific response to SU in TIDM. Nine of the 13 who showed preferential response to glipizide completed a dextrose-only challenge 6 months later and retained marginal C-peptide response to hyperglycemia alone (Δ 0.05 ± 0.04 ng/mL). Whole exome sequencing is pending on these subjects. These data suggest the challenge may serve to elicit and stratify C-peptide response to SU, assist in categorizing residual β-cell function, support screening for monogenic diabetes, and increase consideration of SU therapy for appropriate patients.

Disclosure
A.C.H. Wood: None. M.S. Remedi: None. C. Nichols: None. B.A. Marshall: None.
Racial and Socioeconomic Disparities in Meeting Goals of Care in Adults with Type 1 Diabetes
Authors: HAW J. SONYA , PENG LIMIN , PASQUEL FRANCISCO J. , VELLANKI PRIYATHAMA , FAYFMAN MAYA , DAVIS GEORGIA , UMPIERREZ GUILLERMO E. 
Published: June 2018

Racial and socioeconomic (SES) disparities exist in youth with type 1 diabetes (T1D). Black youth have worse glycemic control, higher frequency of DKA, and less use of insulin pump therapy. However, data is sparse on whether racial and SES disparities in meeting ABC (A1c, Blood pressure, Cholesterol) goals of care exist in adulthood, when financial independence, access to healthcare, and cognitive maturity change.
We used T1D Exchange Network data, which enrolled youth and adults with T1D from 73 practices. We include adults (≥ 18 years) with available race/ethnicity data. Of 12,746 adults, 90% where white, 4.8% black and 5.7% Hispanic; annual household income in 13% was &lt;$25K, 20% was $25-50K, 34% was $50-100K, and 33% was &gt;$100K. Logistic regression showed increased probability of poor glycemic control (A1c &gt;7%) with annual income &lt;$25K (OR 2.29, 95% CI [1.92,1.74]), being black (OR 3.05, 95% CI [2.09,4.43]) or Hispanic (OR 1.42, 95% CI [1.10, 1.82]). Outcomes were similar in achieving SBP &lt;140mmHg and LDL &lt;100mg/dL. Data stratified by income showed significant disparities among races, with fewer black and Hispanic adults achieving ABC goals compared to whites. There were no differences in mortality.
Racial and SES disparities exist in adults with T1D. Racial disparities are evident after adjusting for income, suggesting socio-ecological factors play a role in achieving optimal diabetes care in minority populations.
White, non-HispanicBlack, non-HispanicHispanicp-value&gt;$100K N=2924N=45N=77A1c &lt;7%, n (%)920 (32)4 (9.1)14 (22)&lt;0.001SBP &lt;140 mmHg, n (%)2736 (95)34 (79)69 (92)&lt;0.001LDL &lt;100 mg/dL, n (%)1690 (69)24 (57)43 (67)0.23No smoking, n (%)2218 (95)37 (95)63 (90)0.19$50K-100KN=2914N=99N=105A1c &lt;7%, n (%)751 (26)13 (14)27 (26)0.02SBP &lt;140 mmHg, n (%)2695 (93)88 (89)99 (95)0.20LDL &lt;100 mg/dL, n (%)1607 (65)53 (63)48 (57)0.27No smoking, n (%)2103 (90)87 (97)84 (97)0.01$25K-50KN=1590N=96N=134A1c &lt;7%, n (%)333 (21)8 (8.4)16 (12)&lt;0.001SBP &lt;140 mmHg, n (%)1439 (91)84 (88)124 (93)0.37LDL &lt;100 mg/dL, n (%)828 (65)43 (62)56 (59)0.49No smoking, n (%)1049 (83)76 (87)101 (85)0.52&lt;$25KN=964N=125N=149A1c &lt;7%, n (%)159 (17)6 (5.1)19 (13)0.001SBP &lt;140 mmHg, n (%)890 (93)97 (81)141 (96)&lt;0.001LDL &lt;100 mg/dL, n (%)460 (65)55 (60)61 (53)0.04No smoking, n (%)565 (75)93 (79)123 (89)0.001

Disclosure
J. Haw: None. L. Peng: None. F.J. Pasquel: Consultant; Self; Merck Sharp & Dohme Corp., Sanofi, Boehringer Ingelheim Pharmaceuticals, Inc. P. Vellanki: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc.. Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., AstraZeneca. M. Fayfman: None. G. Davis: None. G.E. Umpierrez: Research Support; Self; Sanofi US, Merck & Co., Inc., Novo Nordisk Inc., AstraZeneca. Advisory Panel; Self; Sanofi, Intarcia Therapeutics, Inc..
Mechanistic Role of IP3R Calcium Release Channel in Pancreatic Beta-Cell Function
Authors: SHU JUN , GAMBARDELLA JESSICA , SORRIENTO DANIELA , SANTULLI GAETANO 
Published: June 2018

Background: According to the classic paradigm, insulin secretion is triggered by the influx of extracellular Ca2+ via voltage-dependent channels, leading to the fusion of insulin granules. Instead, the mechanisms involved in Ca2+ mobilization from internal stores are less defined. The main intracellular Ca2+ release channels are inositol 1,4,5-trisphosphate receptor (IP3R) and ryanodine receptor (RyR), whereas Ca2+ is returned to the ER primarily by the activity of the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) pump. We recently demonstrated the importance of RyR in type 2 diabetes mellitus (T2DM), showing that it is essential in glucose-stimulated insulin secretion (GSIS). Conversely, the exact role of IP3R in GSIS remains not fully understood.
Methods and Results: Three isoforms of IP3R have been identified in mammalian cells. Channel opening is stimulated by the binding of second messenger IP3 and by changes in Ca2+ concentrations. Studies in rodent and human samples indicate that β cells express all IP3R isoforms. We demonstrated that the expression of all isoforms is significantly increased in human islets from T2DM cadaveric donors T2DM compared with nondiabetic individuals. These results were also confirmed in diabetic db/db mice and in mice fed high-fat diet. Moreover, pancreatic β cells from T2DM patients exhibited dysmorphic and dysfunctional mitochondria, with markedly altered Ca2+ uptake. Similar features were found in clonal β cells chronically exposed to high glucose. In vitro, overexpression of IP3Rs was associated with impaired GSIS, whereas IP3R silencing improved β cell function, mitochondrial Ca2+ uptake and function, ER stress, and insulin release in response to different secretagogues.
Conclusions: Taken together, our data indicate that IP3Rs are upregulated in human islets from T2DM donors, leading to mitochondrial dysfunction and pancreatic β cell failure, identifying in these intracellular Ca2+ release channels a novel therapeutic target to treat T2DM.

Disclosure
J. Shu: None. J. Gambardella: None. D. Sorriento: None. G. Santulli: None.
Ethnicity and Common Genetic Variants Modulate Nonalcoholic Fatty Liver Disease (NAFLD) Metabolic Phenotype in Obese Youth
Authors: TRICO DOMENICO , CAPRIO SONIA , UMANO GIUSEPPINA R. , GALDERISI ALFONSO , MATA MARIANA M. , NOUWS JESSICA , PIERPONT BRIDGET , KIM GRACE , SANTORO NICOLA 
Published: June 2018

Background: Pediatric Nonalcoholic Fatty Liver Disease (NAFLD) represents a major risk factor for insulin resistance and type 2 diabetes in adolescents.
Methods: To characterize the clinical and genetic features associated with the development of pediatric NAFLD, 503 obese adolescents (191 Caucasians, 134 African Americans, and 178 Hispanics) underwent a MRI to quantify hepatic fat content, an oral glucose tolerance test to assess glucose tolerance and insulin sensitivity, and the genotyping of three SNPs associated with NAFLD (PNPLA3 rs738409, GCKR rs1260326, and TM6SF2 rs58542926). MRI and metabolic assessments were repeated in 133 patients after 2.27±1.44 years.
Results: The prevalence of NAFLD was 42.9% in Caucasians, 15.7% in African Americans, and 59.6% in Hispanics (p&lt;0.0001). Compared to Caucasians and Hispanics with NAFLD, African Americans adolescents with NAFLD had higher fasting glucose (p=0.03), insulin (p=0.0004), C-peptide (p=0.04), 2-h-glucose (p=0.04), HbA1c (p&lt;0.0001), and lower insulin sensitivity (p=0.03), despite similar age (p=0.34) and gender distribution (p=0.37). This translated in a higher prevalence of prediabetes and type 2 diabetes in African Americans (66.6%) compared to Caucasians (24.4%) and Hispanics (31.1%) with NAFLD (p=0.0003). Analysis of the patients without NAFLD at baseline showed that ethnicity (p=0.02), high C-peptide levels (p=0.0006), changes in z-score BMI over time (p=0.0006) and common gene variants were strong predictors of NAFLD development at follow-up (AUROC curve 0.976).
Conclusions: African American obese adolescents are relatively protected from NAFLD, but are more susceptible to the deleterious effects of NAFLD on glucose metabolism. The combination of ethnicity, markers of insulin resistance and genetic factors are strong predictors of pediatric NAFLD.

Disclosure
D. Trico: None. S. Caprio: None. G.R. Umano: None. A. Galderisi: None. M.M. Mata: None. J. Nouws: None. B. Pierpont: None. G. Kim: None. N. Santoro: None.
Pancreatic Alpha-Cell Function and Identity in Human T2D
Authors: DAI XIAOQING , SOLER JOAN CAMUNAS , BRIANT LINFORD , SPIGELMAN ALIYA F. , HANG YAN , RORSMAN PATRIK , KIM SEUNG , MACDONALD PATRICK 
Published: June 2018

Glucagon is synthesized and released by pancreatic α-cells and, along with insulin, maintains blood glucose levels within the physiological range. We seek to understand the impact of glucose on the biophysical properties of α-cells in T2D. We studied α-cells from human donors (34 nondiabetic, and 14 T2D) and from mice fed a high fat diet (HFD) by whole-cell patch-clamp electrophysiology, with and without combined single-cell RNA sequencing (patch-seq). We found that, opposite to what is observed in β-cells, depolarization-induced exocytosis and Ca2+-channel function is enhanced at low glucose (LG, 1 mM G) and suppressed at high glucose (HG, 5-20 mM G) in nondiabetic (ND) α-cells. This is reversed in α-cells from T2D donors, which display a β-cell-like phenotype where HG amplifies exocytosis and LG inhibits it. Using pharmacological antagonists of Ca2+ channels, we found that LG increases P/Q-type Ca2+ currents in human α-cells, which are specifically linked to glucagon exocytosis. Similar results were obtained from α-cells of HFD mice for 10-14 weeks, where α-cell exocytosis and glucagon secretion were both enhanced, while exocytosis shifted from a dependency on P/Q-type (α-cell-like) to L-type (β-cell-like) Ca2+ channels. Finally, given that the Ca2+ responsiveness of α-cells is variable (suggesting cell- to-cell heterogeneity) and the function of α-cells is dysregulated in diabetes, we applied combined computational approaches and single-cell RNA sequencing with patch-clamp analysis (patch-seq) to link single human α-cell function with transcriptomic profiles. We found distinct α-cell sub-populations in human islets that are either resistant to, or sensitive to, dysfunction in the form of a shift towards a more ’β-cell like’ functional phenotype in T2D. In all, we provide new information to understand normal function of α-cells and important determinants of glucagon secretion in health and diabetes.

Disclosure
X. Dai: None. J. Camunas Soler: None. L. Briant: None. A.F. Spigelman: None. Y. Hang: None. P. Rorsman: None. S. Kim: None. P. MacDonald: None.
CD19+IgM+ Cells from NOD Mice Demonstrate Enhanced Therapeutic Efficacy in Type 1 Diabetes Mellitus
Authors: VONBERG ANDREW D. , PIETROPAOLO MASSIMO 
Published: June 2018

We describe a protective effect on autoimmune diabetes and a reduced destructive insulitis in NOD.scid recipients following splenocyte injections from diabetic NOD donors and sorted CD19+ cells compared to NOD.scid recipients receiving splenocytes alone. This protective effect was age-specific (only CD19+ cells from young NOD donors exerted this effect; p &lt; 0.001). Furthermore, we found that CD19+IgM+ cells is the primary cell subpopulation of B cells that delayed adoptive transfer of diabetes mediated by diabetogenic T cells from NOD mice (p = 0.002). In fact, removal of IgM+ cells from the CD19+ pool did not result in diabetes protection. Blockade of IL-10 with neutralizing antibodies at the time of CD19+ cell co-transfers also abrogated the therapeutic effect, suggesting that IL-10 secretion was an important component of the protective effect. These results were strengthened by ex vivo incubation of CD19+ cells with IL-5, which resulted in enhanced IL-10 production and significantly delayed diabetes progression compared to controls (p = 0.0005). To the best of our knowledge, this is the first study demonstrating that CD19+IgM+ cells is the primary cell subpopulation of regulatory B cells delaying diabetes mediated by diabetogenic T cells from NOD mice. The potential to expand CD19+IgM+ cells, especially in response to increased stimulation using IL-5 or by pharmacologic agents, may be a new therapeutic option for type 1 diabetes.

Disclosure
A.D. Vonberg: None. M. Pietropaolo: None.
Contrast Enhanced Ultrasound with Submicron-Sized Contrast Agents Detects Diabetes Progression in Mouse Models of Type 1 Diabetes
Authors: RAMIREZ DAVID , BENNINGER RICHARD K. 
Published: June 2018

In type 1 diabetes (T1D) the decline in beta-cell mass occurs many years prior to clinical presentation. A non-invasive method to diagnose insulitis and beta-cell mass decline prior to diabetes does not exist. During T1D progression, the islet microvasculature increases permeability due to insulitis. Iron oxide nanoparticle MRI contrast accumulation has previously been suggested as a measure of ongoing insulitis. Contrast enhanced ultrasound (CEUS) using gas-filled microbubbles (MBs) measures acoustic backscatter at sub-harmonic frequencies and is clinically approved. Sub-micron sized ‘nanobubbles’ (NBs) have previously been developed and show extravasation in tumors. Here we tested whether these sub-micron sized NBs show disease-mediated extravasation in mouse models of T1D. We performed CEUS measurements following NB infusion in NOD mice and control (NOD;Rag1ko and C57Bl6) mice. We also examined fluorescent coverage (FC) following rhodamine-labeled bubble delivery in these animals, through isolating pancreata for histology and quantifying FC and insulitis scores. We observed progressive increased CEUS signal accumulation in pancreas of 4w and 10w NOD mice, which was absent in NOD kidneys (p &lt; 0.001). Rag1ko controls showed minimal CEUS signal in pancreas and kidney. The FC was limited to the pancreata of NOD mice and was substantially higher in endocrine compared to exocrine tissue (p = 0.002). NOD mouse islets also had substantially more FC compared to Rag1ko (p &lt; 0.0001), and showed a correlation between NOD insulitis score and FC (p=0.043). Thus, CEUS with NB contrast agents can detect disease progression prior to T1D onset, which will be important for early T1D diagnosis and monitoring of disease prevention or reversal.

Disclosure
D. Ramirez: None. R.K. Benninger: None.