bluuebunny/crossref_metadata_2025_split huggingface dataset:
165-OR: High- and Moderate-Intensity Exercise Training Increased Skeletal Muscle Acylcarnitine and Phospholipid Abundance in Obese Adults
Authors: SCHLEH MICHAEL W. , RYAN BENJAMIN J. , LUDZKI ALISON , GILLEN JENNA B. , HOROWITZ JEFFREY F. 
Published: June 2020

The primary aim of this study was to determine the impact of high-intensity interval training [HIIT] and moderate-intensity continuous training [MICT] on skeletal muscle lipidomic profile in obese adults. 17 obese adults (BMI = 34±3 kg·m-2; age = 31±6 years) completed 12 weeks of either HIIT (10 x 1 min @ 90%HRmax + 1 min recovery between intervals; n=8) or MICT (45 min steady-state exercise at 70% HRmax; n=9). Subjects exercised 4d/week and body weight was strictly maintained to assess the direct effects of exercise, independent of changes in body weight or fat mass. Skeletal muscle samples were collected from the vastus lateralis after an overnight fast both before training and 4 days after the last exercise session (to wash out the acute effects of exercise). Using shotgun lipidomics (LC MS/MS) we detected 734 lipid species from 26 different classes. Neither MICT nor HIIT significantly altered abundance of the primary muscle acylglycerides (tri- and di-acylglyceride) or ceramide abundance. Muscle acylcarnitine abundance increased after both MICT and HIIT (main effect, P = 0.04), specifically polyunsaturated acylcarnitines (P = 0.03). We also found phosphatidylcholine (PC) increased after training in both groups (main effect, P = 0.03), while the increase in phosphatidylethanolamine (PE) was greater after HIIT compared with MICT (P = 0.01). When normalized to cardiolipin (which is found almost exclusively in the inner mitochondrial membrane), the increased abundances of PC and PE were no longer apparent. Therefore, the training-induced increase in these phospholipids may largely reflect increased mitochondrial biosynthesis with training. In contrast, the observed increase in polyunsaturated acylcarnitines may represent an important adaptive response in the coordination of fatty acid metabolism in skeletal muscle after training. Overall, changes in muscle lipid profile were surprisingly similar in HIIT and MICT.

Disclosure
M.W. Schleh: None. B.J. Ryan: None. A. Ludzki: None. J.B. Gillen: None. J.F. Horowitz: None.

Funding
National Institutes of Health (R01DK077966, P30DK089503, F32DK117522, U24DK097153, UL1TR002240); Canadian Institutes of Health Research (DFS146190)
1651-P: Low Leg Fat and Ethnicity Are Predictors for Genetic Insulin Resistance in a Multiethnic Sample of Early Pubertal Children
Authors: FOWLER LAUREN A. , FERNANDEZ JOSE R. , GOWER BARBARA 
Published: June 2020

In the United States, Hispanic- and African-Americans (HA and AA, respectively) have been shown to have a higher prevalence of type 2 diabetes than their European-American (EA) counterparts. A recent genome-wide association study revealed that genetic variants linked to insulin resistance (IR) phenotypes were associated with lower levels of leg fat mass. We investigated whether leg fat deposition and genetic risk for IR differed by ethnicity in a cross-sectional study of 82 AA, 75 HA, and 83 EA children aged 7-12 years. Participants were genotyped with the Metabochip array for 46 single nucleotide polymorphisms (SNPs) associated with IR, and a genetic risk score (GRS) was developed using the weighted sum of the risk alleles. An intravenous glucose tolerance test and minimal modeling were used to derive the insulin sensitivity index (SI), while body composition was measured by DXA. Multiple linear regression was used to compare differences among ethnicity after adjustment for sex, age, Tanner stage, and socioeconomic status. Leg fat models were also adjusted for total body fat and BMI percentile, while SI models were adjusted for adiposity. Mean leg fat deposition relative to total body fat was significantly lower in HA compared to EA and AA (P &lt; 0.001 for both comparisons). Additionally, GRS independently predicted both leg fat (β = -0.34 (0.13), P = 0.012) and SI (β = -1.33 (0.59), P = 0.027) in HA. In contrast, GRS was not an independent predictor of either outcome in AA or EA. These results suggest that HA may have a genetically impaired ability to store lipid in peripheral adipose tissue depots, consequently leading to deposition in ectopic regions and IR. Our findings highlight a potential mechanism contributing to the higher rate of type 2 diabetes observed in Hispanic-American populations.

Disclosure
L.A. Fowler: None. J.R. Fernandez: None. B. Gower: None.

Funding
National Institutes of Health (R01DK067426); National Center for Research Resources (M01RR000032); University of Alabama at Birmingham Nutrition Obesity Research Center (P30DK056336, T32DK062710); University of Alabama at Birmingham Diabetes Research Center (P60DK079626)
1653-P: Association between Genetic Admixture Estimates for Five Ancestral Populations and Diabetes-Related Traits in Pacific Islanders
Authors: HSUEH WEN-CHI , KUMAR PANKAJ , SAFABAKHSH SAIED , JONES LOIS , CURRAN JOANNE , KNOWLER WILLIAM C. , NELSON ROBERT G. , HANSON ROBERT L. 
Published: June 2020

Ecological studies have shown different risks for diabetes (DM) among many ethnic groups, but whether they are due to genetic or non-genetic factors is hard to dissect. We conducted a community-based study aimed at identifying risk factors for DM and related traits in Pacific Islanders from Guam and Saipan. We analyzed the genetic structure of our sample and estimated individual-level admixture using genome-wide SNP data (49,300 variants). We found that genetic ancestry largely derived from 5 populations, representing Marianas Islanders (MI) (mean % heritage, or μ=43%), East Asians (EA, μ=22%), Micronesians (MC, μ=19%), Europeans (EU, μ=13%), and Melanesians (ML, μ=3%). We then tested the association of ancestry estimates with DM, fasting glucose and fasting insulin levels in study participants (n=1,853). Covariates included age, sex and end-stage kidney disease. For fasting insulin, only nondiabetic subjects were used in analyses. All 3 traits were associated with genetic ancestry (p&lt;e-4). EA was associated with lowest DM risk and lowest mean levels of glucose and insulin, while DM risk and fasting glucose were highest in MI. DM risk (measured as odds ratio [OR]) for MI vs. EA was 6.9 (95% CI=3.3-14.7). Mean difference (β) in fasting glucose and insulin for MI vs. EA was 0.83 and 0.76 s.d. units, respectively. MI had higher DM risk compared to MC (OR=1.79, p=0.022), but similar risk to EU and ML. MI had higher mean glucose vs. MC (β=0.23 s.d. units, p=0.014). However, MI had comparable insulin levels to EU and MC, but lower than ML (β=-1.37 s.d. units, p=0.0046).
In summary, there were large and statistically significant differences in DM-related traits among Pacific Islanders with different genetic ancestral backgrounds. Although genetic ancestry estimates may still be confounded by shared environmental factors, the present findings suggest that admixture mapping may be a potentially powerful approach for identifying unique DM loci in Pacific Islanders.

Disclosure
W. Hsueh: None. P. Kumar: None. S. Safabakhsh: None. L. Jones: None. J. Curran: None. W.C. Knowler: None. R.G. Nelson: None. R.L. Hanson: None.
1654-P: Deletion of the Mammalian Indy Homolog (Slc13a5) Improves Hepatic Insulin Sensitivity through Vagal Nerve Signaling
Authors: KURZBACH ANICA , SCHELL MAREIKE , WILLMES DIANA M. , EL-AGROUDY NERMEEN , KLEINRIDDERS ANDRE , BIRKENFELD ANDREAS L. 
Published: June 2020

Background: INDY (I’m Not Dead Yet) is a plasma membrane citrate transporter and is highly expressed in liver and brain. In mammals, whole body deletion of the coding gene (mIndy, Slc13a5) increased energy expenditure and protected mice from diet-induced obesity and insulin resistance. Generation of neuronal mIndy-KO (NINKO) mice revealed improved insulin sensitivity (IS) in these mice, mediated through better hepatic IS. Gene expression studies in wildtype C57Bl/6 mice revealed high expression of mIndy in the hypothalamus (HTM), which is the main brain area regulating hepatic glucose metabolism. One mechanisms is the regulation through AMPK. Reduced hypothalamic AMPK phosphorylation is known to reduce hepatic glucose output, probably mediated via vagal nerve signaling.
Hypothesis: Hepatic glucose production is regulated via mIndy expression in the HTM.
Methods: Hyperinsulinemic-euglycemic clamp studies were performed to assess IS after hepatic vagotomy of NINKO mice. NestinCre+ controls were sham-denervated. Ex vivo brain slices of C57Bl/6 mice and the neuronal hypothalamic cell line CLU183 were acutely stimulated with 1 mM sodium citrate to investigate the effect of citrate on the brain and neurons.
Results: Acute stimulation of brain slices and CLU183 cells with citrate decreased cellular respiration (-19.7%, p≤0.01), ATP production (-37.7%, p≤0.01) and increased AMPK phosphorylation (+24.7%, p≤0.001). In line with that, AMPK phosphorylation in the HTM of NINKO mice was significantly reduced (-68.1%, p≤0.05). With hepatic branch vagotomy, no differences in hepatic IS could be observed anymore (suppression of basal hepatic glucose output (%); NestinCre+: 100.0±27.2, NINKO: 99.4±8.8).
Conclusion: These data suggest that neuronal mIndy is a critical regulator of glucose homeostasis in mammals, probably regulated via AMPK phosphorylation in the HTM and vagal nerve signaling. Further studies will address the exact mechanisms involved in the effect.

Disclosure
A. Kurzbach: None. M. Schell: None. D.M. Willmes: None. N. El-Agroudy: None. A. Kleinridders: None. A.L. Birkenfeld: None.
1659-P: Nutrients Consumption Dependent Association of the Glucagon-Like Peptide-1 Receptor Gene Polymorphism with Insulin Secretion
Authors: NISHIYA YUKI , DAIMON MAKOTO , MURAKAMI HIROSHI , MURABAYASHI MASAYA , MIZUSHIRI SATORU , FUJITA TOMOYUKI , MATSUHASHI YUKI 
Published: June 2020

Objective: Since type 2 diabetes (DM) is a life-style related disease, life-style should be considered, when association between genetic factors and DM are examined. However, most studies did not examine genetic associations with such consideration, as the case of glucagon-like peptide-1 receptor (GLP-1R) gene. We examined the association in consideration with the interaction between the gene polymorphism and various nutrient factors.
Research Design and Methods: Among participants of the population-based Iwaki study of Japanese held in 2014-2017, those with information of the genotype of GLP-1R polymorphism (db SNP ID: rs3765467: A/G)(p.Alg131Gln) as well as nutrients consumed (n=1817) were included. The following individuals were also excluded: 64 on medication for DM, and 52 with FBG levels below 63 mg/dl or over 140 mg/dl (to evaluate HOMA indices precisely). After these exclusions, 1,560 individuals (587 men, 973 women) aged 53.3± 16.1 years were included in the study.
Results: Though not significant, insulin secretion indices assed by homeostasis model assessment (HOMA- ß) in subjects with the GG genotype tended to be lower than in those with the AA+AG genotypes in most groups stratified into tertiles based on their daily nutrients consumptions (high, middle, and low groups). The stratification also showed that the genotype GG was a significant risk for a decreased insulin secretion (HOMA-ß ≤ 30) even after adjustment for multiple factors (age, BMI, drinking alcohol) only in the highest tertiles of energy, protein and carbohydrate consumption in men (odds ratios (95% CI) in high energy, protein and carbohydrate consumption groups: 3.95 (1.03-15.1), 15.83 (1.58-158.9), and 4.23 (1.10-11.2), respectively).
Conclusions: The GLP-1R gene was associated with a decreased insulin secretion dependently of nutrients consumption, which indicates interaction between GLP-1R and nutrient factors on pathophysiology leading to DM.

Disclosure
Y. Nishiya: None. M. Daimon: None. H. Murakami: None. M. Murabayashi: None. S. Mizushiri: None. T. Fujita: None. Y. Matsuhashi: None.
1661-P: NHG-KTPH Monogenic Diabetes Registry: Understanding Monogenic Diabetes in a Multiethnic Asian Population in Singapore
Authors: ANG SU FEN , TAN CLARA SI HUA , KON YIN CHIAN , XIA LIAN , LIM SU CHI 
Published: June 2020

Introduction: Monogenic diabetes (also known as maturity-onset diabetes of the young or MODY) is a rare genetic disorder with an undetermined prevalence in Singapore. The NHG-KTPH Monogenic Diabetes Registry was set up in mid-2017 to capture longitudinal data of individuals genetically diagnosed with monogenic diabetes to study their prevalence and disease trajectories.
Methods: Patients with clinical phenotype suggestive of monogenic diabetes i.e., diabetes onset =&lt;45 years old, BMI &lt;32.5 kg/m2 and GAD autoantibody-negative were recruited and subjected to genetic testing comprising of next-generation 16-MODY gene panel sequencing, mt.3242A&gt;G TaqMan genotyping and multiplex ligation-dependent probe amplification (MLPA) for 4 common MODY genes. Genetic variants annotated as likely pathogenic/pathogenic according to ACMG guidelines were validated using Sanger sequencing. Individuals with such variant(s) were included in the Registry. EQ-5D-5L instrument was also administered for quality of life assessment.
Results: Among 171 patients who were subjected to MODY genetic testing, 26 (15%) were found to harbor likely pathogenic/pathogenic variants. 93% of these variants were found in common MODY genes (HNF1A, HNF4A, GCK, HNF1B, MT-TL1) that had important clinical implications. Biomarkers such as C-peptide, hs-CRP and HDL were significantly different in those with likely pathogenic/pathogenic variants than those without.
Discussion: Monogenic diabetes is present in 15% of our study participants with young-onset diabetes, which is greater than the reported 5% in UK. Clinical demographics and biomarkers can be further evaluated to improve the pick-up rate of monogenic diabetes among young-onset diabetes, with specific calibration applied to different subtypes of monogenic diabetes. This will improve cost-effectiveness of genetic testing and facilitate implementation of precision medicine for individuals with monogenic diabetes.

Disclosure
S. Ang: None. C. Tan: None. Y. Kon: None. L. Xia: None. S. Lim: None.
1666-P: Increased Levels of Autophagy in a Rodent Model of Type 1 Diabetes
Authors: KARACAY CEREN , KOTZBECK PETRA , PRIETL BARBARA , HARER CLEMENS , PIEBER THOMAS 
Published: June 2020

Beta-cell apoptosis is a hallmark of type 1 diabetes (T1D) and type 2 diabetes (T2D). In T2D loss of autophagy has been associated to increased apoptosis and diminished beta-cell mass. In autoimmunity, dysfunctional autophagy alters negative selection of T cells in thymus driving autoreactive immune cells into periphery. Autophagy contributes to presentation of antigens in antigen presenting cells shaping the repertoire of peptides presented to T cells. The aim of this project is to investigate the role of autophagy in the etiology of T1D. To investigate the effect of spermidine (SPD, a known inducer of autophagy) in vivo, non-obese diabetic (NOD) mice received spermidine (10 mM; n=30) or pure drinking water (n=28) from the age of 4 weeks until the age of 35 weeks or diabetes onset. Mice were analyzed for diabetes rate, autophagy markers (LC3-II to LC3-I ratio and p62) and immune cell phenotype in spleen and blood. Spermidine led to a higher diabetes rate in SPD group (80 %) compared to control group (60,7 %) with p-value of 0,026 (log-rank test). Autophagy was induced by diabetes (plasma glucose &gt; 200 mg/dL) and by age. Autophagy levels were higher at 21-35 weeks in old diabetic animals compared to nondiabetic animals at 35 weeks and compared to young diabetic animals at 14-20 weeks (p&lt; 0,0001, and p&lt; 0,0001, respectively). Spermidine treatment increased autophagy levels in pancreas, but diabetic mice at 21-35 weeks still had higher autophagy levels compared to nondiabetic animals at week 35. (LC3-II/LC3-I: p &lt; 0,05; p62: p &lt; 0,05). Spermidine elevated the frequency of natural killer cells in spleen (p &lt; 0,01) and blood (p &lt; 0,01), natural killer T cells (p &lt; 0,01), naïve CD4+ T cells (p &lt; 0,01), naïve CD8+ T cells (p &lt; 0,01) and central memory CD4+ T cells (p &lt; 0,01) in blood. Our experiments indicate that autophagy is induced upon T1D and spermidine-induced autophagy might increase diabetes incidence. Immune cell phenotyping revealed that spermidine promotes immune cells potentially provoking inflammation.

Disclosure
C. Karacay: None. P. Kotzbeck: None. B. Prietl: None. C. Harer: None. T. Pieber: Advisory Panel; Self; ADOCIA, Arecor, AstraZeneca, Eli Lilly and Company, Novo Nordisk A/S, Sanofi. Research Support; Self; AstraZeneca, Novo Nordisk A/S. Speaker’s Bureau; Self; Novo Nordisk A/S, Roche Diagnostics K.K.
1668-P: Novel Mechanism of Negative Regulation of FOXP3 Expression in Autoimmune Diabetes
Authors: RAMAKRISHNAN PARAMESWARAN , DE JESUS TRISTAN J. , CENTORE JOSHUA 
Published: June 2020

The NF-kappaB protein c-Rel is essential for the expression of forkhead box P3 (FOXP3), the master transcription factor that governs development and function of T regulatory cells. We found that O-GlcNAcylation of c-Rel at serine residue 350 suppresses the expression of FOXP3. Hyperglycemia-induced c-Rel O-GlcNAcylation-dependent suppression of FOXP3 expression was found in vivo in two mouse models of autoimmune diabetes; the streptozotocin (STZ)-induced diabetic mouse model and in the non-obese diabetic (NOD) mouse model. Mechanistically, we show that both hyperglycemia-induced and chemically enhanced cellular O-GlcNAcylation decreases the DNA binding ability of c-Rel at the FOXP3 promoter. Mutation of the O-GlcNAcylation site in c-Rel, (serine 350 to alanine), augments T cell receptor-induced FOXP3 expression and resists the O-GlcNAcylation-dependent repression of FOXP3 expression. This study reveals c-Rel S350 O-GlcNAcylation as a novel molecular mechanism regulating immunosuppressive FOXP3 expression in autoimmune diabetes with potential therapeutic implications.

Disclosure
P. Ramakrishnan: None. T.J. de Jesus: None. J. Centore: None.

Funding
National Institutes of Health (R01AI116730, R21AI144264)
167-LB: The Contribution of a- to ß-Cell Transdifferentiation in Gestational ß-Cell Expansion in Mouse
Authors: SZLAPINSKI SANDRA , BENNETT JAMIE , STRUTT BRENDA , HILL DAVID J. 
Published: June 2020

Introduction: Pregnancy is characterized as a state of insulin resistance. To compensate for this, endocrine pancreatic β-cell mass (BCM) expansion occurs and is maximal at gestational day 18 (GD18) in mouse. There is evidence through lineage tracing of α-cells that they can replenish β-cells following β-cell loss/stress by α to β-cell transdifferentiation. In this study we sought to track the fate of α-cells during pregnancy to determine the contribution of α to β-cell transdifferentiation in gestational BCM expansion.
Hypothesis: α to β-cell transdifferentiation will be higher during pregnancy compared to a non-pregnant animal.
Materials and Methods: Glucagon-Cre/Rosa26-eYFP mice were time-mated and a non-pregnant group was age-matched to these animals. Pancreata were removed on GD9, 12, 18, and postpartum day 7 for fluorescence immunohistochemistry. Tissue sections were immunostained for insulin, YFP, glucagon, DAPI and analyzed by manual cell counting. All insulin-expressing cells were counted and separated into either islets (≥6 β-cells) or clusters (1-5 β-cells).
Results: There were more transitional cells (Insulin+YFP+Glucagon+) in clusters during pregnancy compared to a non-pregnant animal (13.31±4.53%vs.9.14±2.01%). Furthermore, there were more differentiated β-cells with an α-cell origin (Insulin+YFP+Glucagon-) during pregnancy compared to a non-pregnant animal (16.73±5.28% vs.5.79±3.27%).
Discussion and Conclusions: The data show more transitional cells during pregnancy, followed by an increase in β-cells differentiating from α-cells. Our previous experiments found that BCM expansion occurs in part due to neogenesis from β-cell progenitors located in clusters. Since there were more transitional cells localized to clusters, it is plausible that α to β cell transdifferentiation is enriched in clusters. This study provides mechanistic insights into the pathology of β-cell deficiency in pathological pregnancies such as gestational diabetes.

Disclosure
S. Szlapinski: None. J. Bennett: None. B. Strutt: None. D.J. Hill: None.

Funding
Ontario Graduate Scholarship; Lawson Foundation; St. Joseph’s Health Care Foundation
1673-P: Plasmablasts Contribute to the Development of Type 1 Diabetes via Enhancing T-Cell Cytotoxicity
Authors: YAN BI , LING QING , LU JING , ZHU DALONG 
Published: June 2020

Disturbance of innate and adaptive immune systems is responsible for β-cell destruction in type 1 diabetes (T1D). Although increasing evidence indicated a crucial role for B cells in disease pathogenesis, exactly how B-cell subsets contribute to T1D remains unclear. This study aimed to evaluate the potential role of B-cell subset in the development of T1D. We enrolled 56 people with T1D, including 8 people receiving mesenchymal stromal cell (MSC) treatment, 22 people with T2D, and 26 healthy controls. ELISPOT assay was used to assess the role of B-cell subset in activation of diabetogenic T cells. NOD mice and adoptive transfer assays were utilized to study the role of B-cell subset in T1D in vivo. Plasmablasts, but not naïve, unswitched or switched memory B cells, were increased in patients with recent-onset T1D, compared with those with long-term T1D, T2D and healthy controls. In patients with recent-onset T1D, plasmablast number negatively correlated with fasting C-peptide and area under the curve of C-peptide. Plasmablasts decreased in line with an improvement of residual β-cell function 3 months after MSC treatment. Compared with other B-cell subsets, plasmablasts expressed a high level of CD86, which negatively correlated with the residual β-cell function while positively correlated with the number of islet autoantibodies. ELISPOT assay further showed that plasmablasts isolated from participants with T1D induced a dramatic increase of interferon-γ secretion in GAD65 stimulated T cells. Compared with euglycemic NOD mice, the number of plasmablasts was increased in the spleen, pancreatic lymph nodes, and islets of diabetic NOD mice. Moreover, adoptive transfer of plasmablasts mixed with T cells from diabetic NOD mice into NOD/SCID mice accelerated the development of T1D. These data firstly demonstrated that plasmablasts play a vital role in immune disturbance, further expanding the knowledge of T1D pathogenesis. Plasmablasts may serve as a novel therapeutic target in T1D.

Disclosure
B. Yan: None. Q. Ling: None. J. Lu: None. D. Zhu: None.