bluuebunny/crossref_metadata_2025 huggingface dataset:
1490-P: Diabetes Induces Impaired Fibrotic Response to Mesh Involving Macrophage Dysfunction
Authors: LIANG RUI
Published: June 2024

Introduction: Women with diabetes have ~5-fold increased risk of mesh exposure into vaginal cavity following synthetic mesh augmentation in the surgical repair of pelvic floor disorders. To define the mechanism relevant to host fibrotic response, we studied the impact of diabetes on fibrillogenesis at mesh-tissue interface with a focus on the role of macrophages.

Methods: Diabetes was induced in Wistar rats using streptozotocin for 2 weeks. Rats w/wo diabetes underwent mesh implantation via sacrocolpopexy for 7- and 42-days (n=8 per time point per group). Fibrotic response (350μm adjacent to mesh), including thinner (G) vs. thicker (R) fibers and collagen density were quantified in Picrosirius Red images. TGF-β1 level in tissue extracts was measured using ELISA. Macrophage transcriptomics was sequenced following tissue dissociation and flow-sorting. CD68+αSMA+ cells were examined in tissue sections using immunofluorescence. CLC Genomics Workbench 22 (fold change>2, FDR<.05) and Mann-Whitney tests (p<.05) were used for statistics.

Results: In nondiabetics, the fibrotic response progressed with an increase in collagen density (p=0.008), and a decrease in TGF-β1 (p=.007) over time. The R/G ratio was not changed (p=.45). In contrast, diabetics displayed a deregulated pattern with impaired formation of thicker R fibers (p=.009), resulting in increased G fibers (p=.007) and decreased R/G (p=.014) at 42- vs. 7- days, while the collagen density and TGF-β1 level were unchanged over time (p=.49, .75). Paradoxically, macrophage expression of αSMA (myofibroblast marker) and major collagens (I, III, VI and VI) was increased ~4-fold relative to those in the nondiabetics at 42 days (FDR<.05). Cells with positively co-labeled CD68 (macrophage marker) and αSMA were identified at mesh-tissue interface.

Conclusions: Long-term diabetes negatively impacts host fibrotic response to mesh. The increase of macrophage-myofibroblast trandifferentiation in the process is yet to be elucidated.

Disclosure

R. Liang: None.

Funding

National Institutes of Health (R01HD108666)
1501-P: Four Loci, Four Fates—Differential Regulation of IRF5 Promoter in Prodiabetogenic Stress
Authors: AL MADHOUN ASHRAF , AREFANIAN HOSSEIN , KOCHUMON SHIHAB P. , AKHTER NADEEM , WILSON AJIT , ALBELOUSHI SHAIMA , ALRASHED FATEMA , BAHMAN FATEMAH , AL-MANSOUR NOURAH , ALZAID FAWAZ , ALMULLA FAHD , AHMAD RASHEED , SINDHU SARDAR T.
Published: June 2024

Introduction: Interferon regulatory factor (IRF)-5 is a transcription factor sitting at the crossroads of diverse cell processes. Emerging evidence supports its upregulation in response to different stimuli, however, the associated molecular mechanisms remain elusive.

Methods: Four distinct IRF5 regulatory loci 1A, 1B, 1C, & 1D were individually cloned into Luciferase-based reporter vectors. RAW 264.7 macrophage cells were transfected with each of four reporter constructs and cells were exposed for 24h to stress stimuli including 100 µM palmitate (saturated FA), 100 µM oleate (unsaturated FA), 100 µM H2O2 (ROS inducer), 100 ng/mL TNF-α (inflammatory cytokine), 25 mM glucose (hyperglycemia), or 30 ng/mL IFN-γ (inflammatory cytokine). Luciferase activity was measured and normalized to Renilla luciferase activity. In additional experiments, co-transfections were performed using each promoter construct and expression vectors for E2F, NRF2, and STAT3 to investigate their potential roles. Statistical analysis was performed using two-way ANOVA.

Results: Luciferase assays revealed a differential response of the four IRF5 promoter loci. IRF5-1C exhibited the least significant regulation in mouse macrophages. Alternatively, 1A, 1B, and 1D displayed the increased reporter activities (300-fold compared to the control construct). Palmitate and H2O2 treatments triggered activation at all four promoter sites, while oleate stimulated only the 1D promoter region. Interestingly, TNF-α, hyperglycemia, and IFN-γ failed to induce IRF5 promoter activity at any of these loci. Co-transfections with transcription factor E2F stimulated luciferase activity at all four promoter loci, NRF2 stimulated activity at loci 1A, 1B, and 1D, and STAT3 stimulated activity at loci 1A and 1B.

Conclusion: Our findings demonstrate that the four IRF5 promoter loci exhibit distinct responses to stimuli that mimic the pro-diabetogenic stress via the mechanism involving specific transcriptional regulators.

Disclosure

A. Al Madhoun: None. H. Arefanian: None. S.P. Kochumon: None. N. Akhter: None. A. Wilson: None. S. Albeloushi: None. F. Alrashed: None. F. Bahman: None. N. Al-Mansour: None. F. Alzaid: None. F. Almulla: None. R. Ahmad: None. S.T. Sindhu: None.

Funding

Kuwait Foundation for the Advancement of Sciences (KFAS) (RA 2015-027)
1509-P: The Mesenchymal Stromal Cells in “Neo-islets,” Islet-Sized 3D Organoids Composed of MSCs and Islet Cells That Functionally Cure Type 1 Diabetes, Actively Preserve Normal ATP Levels and Viability of ICs In Vitro and In Vivo—Applicable to Islet and iPSC-Derived Therapies of Type 1 Diabetes Mellitus
Authors: GOOCH ANNA , WESTENFELDER CHRISTOF
Published: June 2024

Allotransplants of pancreatic islets in patients with T1DM require their isolation from deceased donor pancreata. This process results in the ischemic loss of up to 50% of islets. Their intraportal administration leads to further islet death due to low oxygen pressure, the Instant Blood-Mediated Inflammatory Reaction and subsequent exposure to high concentrations of orally administered cytotoxic anti-rejection drugs. Despite the use of anti-rejection drugs, a significant percentage of transplanted islets lose their function over time and need to be replaced. The objective of the current study was to determine whether MSCs that are co-aggregated (1:1 ratio) with ICs in “Neo-Islets” protect IC viability by maintaining their ATP levels. This was tested by in vitro exposure x 24 hrs. of cultured human MSCs, ICs and “Neo-Islets” to 1% pO2. Not unexpectedly, at 24 hrs of hypoxia ATP levels of cultured human ICs (P2) fell from 78±10 to 40±2 pg/cell (p=0.02) and viability decreased to 50%, while ATP levels and viability of identically cultured MSCs remained normal, likely Pasteur effect mediated. Significantly, total ATP levels in freshly formed Neo-Islets remained normal during hypoxia and viability remained close to 99%. Several groups have now demonstrated that MSCs transfer mitochondria though nanotubes into hypoxically stressed neighboring cells, a process that enhances ATP levels and thereby improves their survival.

Conclusion: This ATP-mediated cytoprotective activity of MSCs, combined with their anti-apoptotic, immune-isolating, anti-inflammatory, angiogenic and other trophic actions are exploited in “Neo-islets”. The utility of this co-aggregation technology will be tested to determine whether it can significantly improve islet and novel iPSC-derived transplants that are used to treat patients with T1DM.

Disclosure

A. Gooch: Employee; SymbioCellTech, LLC. Board Member; SymbioCellTech, LLC. Stock/Shareholder; SymbioCellTech, LLC. C. Westenfelder: None.
1516-P: Epigenetic Changes in Insulin Signaling Genes and Cancer Pathway Genes with Remission of Prediabetes
Authors: STENTZ FRANKIE B. , AMMONS ANN
Published: June 2024

Prediabetes or impaired glucose tolerance (IGT) is often seen in conjunction with obesity and both are associated with increased incidence of various diseases. The purpose of this study was to determine if epigenetic changes of DNA occur in patients that convert from prediabetic to normal glucose tolerance(NGT) by determining DNA methylation at baseline and at remission of prediabetes at 6 months (mo).

Methods: 24 obese adults with prediabetes were randomized to a High Protein (HP)(30% protein(P), 30% fat(F), 40% carbohydrates(C)) or High Carbohydrate (HC)(15%P, 30%F, 55%C) diet for 6 mo with all food provided. Oral Glucose Tolerance Test (OGTT) was performed at Baseline (BL) and 6 mo to determine IGT/NGT status. DNA was extracted from BL and 6 mo OGTT 0-minute blood samples. Specific site DNA methylation was determined.

Results: The HP diet group had 100%(12/12) conversion to NGT while the HC diet had 33%(4/12) conversion. Both diet groups had weight loss and improvement in insulin sensitivity determined by Matsuda Index [HP(BL 2.3 ± 0.3; 6 mo 6.5 ±1.1)], [HC(2.3±0.3; 6 mo 3.2±0.4)]. Changes in DNA methylation of numerous genes were observed from BL to 6 mo with remission of prediabetes and weight loss. Some of these genes with altered DNA methylation include the KEGG pathways of: insulin signaling(IS)(11 genes), cardiovascular disease(CV)(15 genes), inflammation(IF)(18 genes), metabolic pathways(MP)(32 genes), and cancer pathways(31 genes). Changes in DNA methylation of genes involved in IS, CV, MP, correlate with the improvements in IS, CV and IF in the subjects after 6 months on the diets. Of the cancer pathway genes and insulin signaling and inflammation genes 18 of the changes in DNA methylation of the genes were the same.

Conclusions: The HP diet was the most effective with respect to DNA methylation changes and clinical parameters. The DNA methylation changes of specific genes may be important for reduction of certain disease states and can be improved by diet and weight loss.

Disclosure

F.B. Stentz: None. A. Ammons: None.
1517-P: Rev-Erba as an Intermediate between Regulation of Circadian Rhythm and Skeletal Muscle Insulin Sensitivity
Authors: MUÑOZ VITOR R. , PINTO ANA PAULA S.R. , LINO MARSEL , SILVA ADELINO S.R. , RONALD KAHN C.
Published: June 2024

Rev-Erbα is a nuclear receptor involved in the control of circadian rhythm and regulates the transcription of many metabolic genes. Skeletal muscle is responsible for >75% of postprandial glucose uptake, and this is significantly reduced in insulin-resistant and type 2 diabetic (T2D) individuals. To determine the potential role of Rev-Erbα in muscle in T2D, we have used human induced pluripotent stem cells (iPSCs) from control and T2D patients differentiated into myoblasts (iMyos) to study its role in insulin action and metabolism in the absence of confounding circulating factors. We find that iMyos from T2D donors have a 25% decrease (p=0.005) in the Rev-Erbα mRNA expression, and this is paralleled by a 35% decrease (p=0.03) in Rev-Erbα protein. This is also accompanied by significant 22-45% reductions in insulin-stimulated phosphorylation of pIRβY1146, pIRS1Y895, pAktS473, pGSK3βS9, and an ~30% decrease in insulin-stimulated glucose uptake. Treatment of T2D iMyos with a Rev-Erbα agonist rescues the impaired glucose uptake in the T2D cells to control levels. CRISPR/Cas9 knockout of Rev-Erbα in murine C2C12 muscle cells results in reduced insulin-stimulated insulin signaling and glucose uptake, paralleling the defects observed in the human T2D iMyos. RNAseq analysis of these knockout cells revealed changes in expression of genes associated with insulin action, including downregulation of Irs2, Gab1, and Shc2. Combining these data with Rev-Erbα ChipSeq data identified 150 genes in the Rev-Erbα-/- cells that are directly targeted and repressed by Rev-Erbα via its binding in the promoter region. These genes are enriched in pathways related to mitochondria physiology and insulin resistance. Taken together, these data demonstrate that Rev-Erbα provides cross-talk between circadian regulation and metabolism by acting as a positive regulator of insulin sensitivity, glucose uptake and mitochondrial function, and this process is attenuated in skeletal muscle in human T2D.

Disclosure

V.R. Muñoz: None. A.S.R. Pinto: None. M. Lino: None. A.S.R. Silva: None. C. Kahn: Consultant; Cellarity. Other Relationship; 1825 Therapeutics. Advisory Panel; TIXiMED, Senseion, ERX.
1549-P: Hyperamylinemia and Its Implications on Brain Function—Amylin Deposition and Cognitive Alterations—A Cross-Sectional Study
Authors: CHOUDHARY BINOD K. , KHAN KAMRAN , KUMAR SANJAY , SHARMA HEM S.
Published: June 2024

Introduction: Hyperamylinemia, a condition characterized by elevated levels of amylin, may contribute to amyloid deposition in the brain, akin to the amyloid plaques observed in Alzheimer's disease. This cross-sectional study explores the relationship between hyperamylinemia, amylin deposition in the brain, and subsequent effects on brain function.

Methodology: In this cross-sectional study, 120 subjects were divided into normoamylinemic (n=60) and hyperamylinemic (n=60) groups based on serum amylin levels. Participants received clinical evaluations, cognitive tests, and brain imaging. Brain tissues from deceased hyperamylinemic subjects were examined for amylin deposits. Statistical methods, including logistic regression and correlation matrices, analyzed the link between amylin levels, brain deposits, and cognitive function.

Results: The hyperamylinemic group showed 45% more amylin deposition in memory-related brain regions than the normoamylinemic group (p<0.01). Cognitive scores were 30% lower in hyperamylinemics, correlating with their amylin levels (p<0.05). Amylin aggregates were found in 80% of hyperamylinemic subjects. A strong correlation (r=0.78, p<0.001) was observed between hyperamylinemia, amylin brain deposits, and reduced cognitive performance.

Conclusion: Hyperamylinemia is linked to amylin accumulation in the brain and cognitive impairment, suggesting its role as a risk factor for Alzheimer's-like neurodegenerative conditions. Exploring amylin's brain functions may reveal new treatments for these diseases. Future studies are needed to clarify these mechanisms and relationships.

Disclosure

B.K. Choudhary: None. K. Khan: None. S. Kumar: None. H.S. Sharma: None.
1553-P: Estimated Beta-Cell Function and BMI Do Not Explain Racial/Ethnic Differences in Diabetes Incidence in People with Prediabetes
Authors: VAZQUEZ ARREOLA ELSA , HANSON ROBERT L. , KNOWLER WILLIAM C.
Published: June 2024

Introduction & Objectives: All Diabetes Prevention Program (DPP) participants had prediabetes and received the same interventions (lifestyle, metformin, or placebo), but racial/ethnic differences in diabetes incidence emerged in follow-up, which we try to explain by differences in beta-cell function.

Methods: In 1671 self-identified white (W), 618 black (B), and 487 Hispanic (H) participants in DPP repository data, we analyzed insulin sensitivity index (ISI) and response to oral glucose (30-minute corrected insulin response, CIR) during 17 years of follow-up.

Results: Incidence was 7.5 cases/100 person-years in B, 6.0 in H, and 5.4 in W. B and H had higher rates than W, adjusted for age, sex, and intervention (B: HR=1.35, 95%CI=1.19-1.53; H: HR=1.07, 0.93-1.24) and when further adjusted for BMI, ISI, and CIR (B: HR=1.48, 1.30-1.68; H: HR=1.15, 0.99-1.33). Lower baseline BMI and higher ISI and CIR were protective but did not explain the race/ethnicity effects. Longitudinal relationships of ISI and CIR differed by race/ethnicity (Figure); paradoxically B had the highest CIR which would predict lower diabetes incidence.

Conclusion: Higher diabetes incidence in B was not explained by differences in BMI or beta-cell function. We hypothesize that B with prediabetes compensate for other, unknown, risk factors by increasing CIR which, in many, is insufficient to prevent diabetes.

Disclosure

E. Vazquez Arreola: None. R.L. Hanson: None. W.C. Knowler: None.

Funding

Intramural Research Program of the National Institute of Diabetes and Digestive and Kidney Diseases
1560-P: Inflammation in the Exocrine Pancreas Impairs Insulin Secretion
Authors: STEIGER LAURA , MEIER DANIEL T. , RACHID LEILA , MEREAU HELENE , DONATH MARC Y. , DE BAAT AXEL , BOENI-SCHNETZLER MARIANNE
Published: June 2024

Introduction: In patients with type 2 diabetes, increasing evidence points to pathological changes not only in the endocrine but also in the exocrine pancreas. In particular, the number of immune cells is increased in both compartments. Furthermore, patients with chronic pancreatitis, a form of exocrine inflammation, have an increased risk to develop diabetes. However, the causal relationship between exocrine pathologies and impaired endocrine insulin secretion is unknown.

Methods: We established a mouse model of chronic pancreatitis using caerulein injections, thereby stimulating digestive enzymes secretion in exocrine cells. Over 3 weeks, wild-type mice underwent treatment combined with a high-fat diet to induce insulin resistance. To avoid body weight differences due to the anorexic effect of caerulein, saline-treated control mice were pair-fed. We evaluated insulin secretion and glucose metabolism by in vivo glucose tolerance testing and assessing ex vivo glucose-stimulated insulin secretion in isolated islets. Pancreata were immunohistochemically evaluated and transcriptional changes in islets were studied using RNA sequencing.

Results: Chronic pancreatitis in caerulein-treated mice was confirmed by elevated immune cells in the exocrine pancreas, whereas no increase in immune cells was observed in islets. Functionally, mice with chronic pancreatitis had severely impaired insulin secretion and resulted in hyperglycemia compared to the saline-treated control mice. Islets isolated from caerulein-treated mice showed reduced glucose-stimulated insulin secretion. Surprisingly, despite exocrine tissue destruction and reduced exocrine tissue mass, β-cell mass was not reduced. Further, differentially expressed genes were not associated with β-cell signatures but with extracellular matrix components.

Conclusion: Impaired insulin secretion in chronic pancreatitis may be due to alterations in the extracellular matrix components of the islets rather than to destruction of β-cells.

Disclosure

L. Steiger: None. D.T. Meier: None. L. Rachid: None. H. Mereau: None. M.Y. Donath: Advisory Panel; Novo Nordisk, Lilly Diabetes, Boehringer-Ingelheim. Research Support; Boehringer-Ingelheim, Olatec. A. de Baat: None. M. Boeni-Schnetzler: None.

Funding

Swiss National Science Foundation ( 320030_214900)
1607-P: Estimation of Muscle and Hepatic Insulin Sensitivity in Type 1 Diabetes Adults Using Clinical and Research Biomarkers
Authors: JANUSZEWSKI ANDRZEJ S. , SNAITH JENNIFER R. , KOWALSKI GREG M. , BRUCE CLINTON , HOLMES-WALKER JANE , JENKINS ALICIA , GREENFIELD JERRY
Published: June 2024

Background and Aims: Impaired insulin sensitivity in type 1 diabetes (T1D) is an under-appreciated cardiovascular risk factor yet is challenging to measure. Euglycemic hyperinsulinemic clamps are the “gold standard” for quantifying insulin sensitivity. Adding stable isotope-labeled glucose allows for differentiation of hepatic and muscle insulin sensitivity (assessed by endogenous glucose production [EGP] and glucose infusion rate [GIR] respectively). Non-invasive estimation of both EGP and GIR using biomarkers has not been previously assessed in T1D.

Methods: Two-step clamps were conducted in 40 adults with T1D in the INTIMET trial (INsulin resistance in Type 1 diabetes managed with METformin, ACTRN12619001440112). Subjects were characterized with 33 clinical and research biomarkers. Exhaustive search (XLStat, Lumivero, Denver, CO) was used to derive equations correlating with baseline clamp-quantified EGP and GIR.

Results: Exhaustive search analyses derived a formula predicting unfavorable GIR (dichotomous variable: below median of 60.4 µmol/kgFFM/min) using: total daily insulin dose (TDI), fasting triglycerides (TG), insulin-like growth factor-1 and aspartate aminotransferase (AST) levels, with an AUROC of 0.97, p<0.0001, R2 (Nagelkerke)=0.78, 92.5% accuracy. A model predicting unfavorable EGP level (above median of 6.2 µmol/kgFFM/min) contained four variables: TDI, TG, alkaline phosphatase and uric acid levels, with an AUROC of 0.86, p=0.001, R2 (Nagelkerke) of 0.47, 80% accuracy. Our free online calculator (available at https://bit.ly/EGP-GIR-calculator) enables estimation of GIR and EGP by these binary categories.

Conclusions: Tissue specific estimation of insulin sensitivity is feasible in T1D using clinical and research biomarkers. Incorporating estimates of hepatic and muscle insulin sensitivity in clinical trials may predict response to lifestyle and drug interventions. Validation studies are merited.

Disclosure

A.S. Januszewski: None. J.R. Snaith: None. G.M. Kowalski: None. C. Bruce: None. J. Holmes-Walker: None. A. Jenkins: Research Support; Abbott, Viatris Inc. Advisory Panel; Abbott. Research Support; Medtronic. Board Member; Insulin for Life. Research Support; Leona M. and Harry B. Helmsley Charitable Trust, Juvenile Diabetes Research Foundation (JDRF), Jaeb Center for Health Research, National Institutes of Health, National Health and Medical Research Council Australia. J. Greenfield: Other Relationship; Novo Nordisk.
161-OR: Type A Insulin Resistance Can Be Misdiagnosed as Type 1 or Type 2 Diabetes—A Cautionary Tale
Authors: WIRTHWEIN KACI , LOS EVAN A.
Published: June 2024

We present the case of a 19-year-old male presumed to have type 1 diabetes diagnosed at age 14. He was treated as such until requiring escalating doses of insulin and metformin. He was then lost to follow-up and after self-discontinuing insulin for approximately 1 year, he re-presented with hyperglycemia, the absence of ketonuria or acidosis, and elevated insulin level without use of exogenous insulin. Subsequent genetic testing revealed a mutation in the insulin receptor gene (INSR) consistent with type A insulin resistance. We then contrast the case of his 15-year-old maternal half-brother who has an identical gene mutation. However, this second patient was independently evaluated and diagnosed at age 9 with type 2 diabetes. He presented with significantly elevated BMI, acanthosis nigricans, as well as suboptimal diet and exercise habits. He required escalation of type 2 diabetes treatment to achieve effective glucose control and management of obesity. The case of a half-brother pair with essentially opposite presentations of the same genetic mutation consistent with type A insulin resistance has never been described in the literature.

Disclosure

K. Wirthwein: None. E.A. Los: None.
1611-P: vPIVOT MRI as a Novel Strategy to Assess Vascular Function in COVID and Type 2 Diabetes
Authors: ENGLUND ERIN , BARKER ALEX J. , MEDRANO GABRIEL I. , CREE-GREEN MELANIE , MAICKI RICHARD , DOUGLAS IVOR S. , REUSCH JANE E.B.
Published: June 2024

Introduction & Objective: Diabetes and SARS-CoV-2 target the endothelium, causing microvascular dysfunction. We present a novel test to measure recovery dynamics of blood flow post-isometric exercise in the leg. We hypothesized that T2D related microvascular injury would augment perfusion abnormalities in people with COVID-19.

Methods: 14 hospitalized adults with COVID-19 and acute hypoxemia (7 with DM) underwent vPIVOT MRI on a 3T scanner 1 month post hospitalization. Scans were compared to 4 healthy controls (no DM or severe COVID-19). vPIVOT is an MRI sequence that simultaneously measures micro- and macrovascular blood flow and oxygenation, enabling quantification of integrated peripheral vascular responses to hyperemic stimuli, such as exercise. Here, the perfusion response following a 90s isometric plantar flexion contraction at 70% maximum effort was analyzed.

Results: Quantitative analysis of the MRI data was performed as shown (Figure). Significant between group differences of area under the curve (AUC, p=0.021) and time to recovery (TTR, p=0.024) were observed by ANOVA. Post-hoc comparisons did not detect any significant differences in COVID-19 participants with or without T2DM in this limited sample.

Conclusion: We demonstrate a novel MRI exam can elucidate total perfusion after exercise, and preliminary results show that it is reduced in time and in magnitude for people post severe COVID-19 infection.

Disclosure

E. Englund: None. A.J. Barker: None. G.I. Medrano: None. M. Cree-Green: Consultant; Pollie, Inc. Research Support; Amino Co. R. Maicki: None. I.S. Douglas: None. J.E.B. Reusch: Advisory Panel; Medtronic.

Funding

NIH (R01 DK130351); NIH/NCATS Colorado CTSA (KL2TR002534); American Heart Association (853697)
1621-P: Lower Osteocalcin Levels Are Associated with Abnormal Adipose Tissue Distribution and Higher Cardiovascular Risk in People with Autoimmune Diabetes
Authors: RISI RENATA , AMENDOLARA ROCCO , BALENA ANGELA , MASI DAVIDE , D'ONOFRIO LUCA , WATANABE MIKIKO , GNESSI LUCIO , MADDALONI ERNESTO , BUZZETTI RAFFAELLA
Published: June 2024

Introduction & Objective: Osteocalcin (OCN) plays a role on adipose tissue (AT) and cardiovascular risk (CVR) in subjects with diabetes. Aim: to evaluate the relation between OCN, AT and CVR in autoimmune diabetes (AD).

Methods: In this cross-sectional study, body composition was evaluated with DXA-scan in subjects with AD. Adipokines (vaspin, leptin, adiponectin) and OCN were measured. CVR was assessed by the Steno T1 risk engine score (ST1RES). Logistic regression was used to determine predictors of medium/high CVR.

Results: Sixty-two patients (median age 49.4 [23-79] years, HbA1c 7.9 [5.7-10.7]%, BMI 25.8[17.2-46.8] Kg/m2) were enrolled. OCN was negatively associated with upper body fat deposition index (UBDFI, p .002 β -.4) and vaspin (p .01, β -.3), positively with adiponectin (p .01 β .3). Patients with lower OCN levels showed higher CVR risk (fig1). A logistic binary regression for including UBFDI, OCN, vaspin, adiponectin as independent variables showed that UBFDI and adiponectin were significant predictors of CVR in AD (R square .356).

Conclusion: The association between OCN and adiposity markers suggests its involvement in AT regulation. Nonetheless, patients with lower OCN levels showed higher CVR, suggesting that OCN might be involved in CVR in AD by regulating AT.

Disclosure

R. Risi: None. R. Amendolara: None. A. Balena: None. D. Masi: None. L. D'Onofrio: None. M. Watanabe: None. L. Gnessi: Consultant; Novo Nordisk. E. Maddaloni: Advisory Panel; Novo Nordisk, Merck Sharp & Dohme Corp. Speaker's Bureau; Abbott, Eli Lilly and Company. Consultant; PikDare. Speaker's Bureau; MTD. R. Buzzetti: Consultant; Abbott, Eli Lilly and Company, Sanofi, Novo Nordisk, AstraZeneca, Boehringer-Ingelheim.

Funding

D3 4 Health—Digital Driven Diagnostics, Prognostics and Therapeutics for Sustainable Health Care (PNC0000001)
1625-P: GS-4571, an Oral Small Molecule GLP-1R Agonist, Improves Glucose Tolerance and Suppresses Food Intake in Obese Diabetic Cynomolgus Monkeys
Authors: VOGEL JEN , SEUNG MINJI , MARCHAND BRUNO , BHANGRE NEERAJA , MUKHERJEE JIT , AMMANN STEPHEN E. , ARMSTRONG MEGAN , BRIZGYS GEDIMINAS , CHIN ELBERT , CHOU CHIEN-HUNG , COTTELL JEROMY , SCHROEDER SCOTT D. , THOMAS-TRAN RHIANNON , YANG ZHENG-YU , PETERS MICHAEL , BUDAS GRANT , MITCHELL MICHAEL L. , CHOJNACKA MAJA , JERMAIN SCOTT , HUNG JOEY , KULKARNI SUPRIYA , YUE QIN , LIN DAVID W. , MIRANDA DIEGO A.
Published: June 2024

The Glucagon-like peptide 1 receptor (GLP-1R) is a class B1 G-protein-coupled receptor (GPCR) that is widely expressed and helps mediate insulin secretion, gastric emptying, and satiety. Currently, GLP-1R peptide agonists are used as standard of care for the treatment of T2DM and more recently for obesity. These GLP-1R peptide agonists require frequent subcutaneous injections or strict dosing guidelines thus increasing the need to develop an oral small-molecule GLP-1R agonist. Here we describe the identification of a novel small molecule GLP-1R agonist (GS-4571) which stimulated a potent cAMP response in pancreatic β-cells (EndoC-BH1) and selective agonism against human and monkey GLP-1R versus other class B GPCRs. In an intraperitoneal glucose tolerance test (IPGTT) it demonstrated improved glucose tolerance in humanized GLP-1R mice. Further studies, in obese cynomolgus monkeys, GS-4571 demonstrated similar improvements in glucose tolerance after a single dose treatment. Once-daily oral administration of GS-4571 in obese diabetic cynomolgus monkeys not only showed improved glycemic control but also showed a reduction in energy intake which led to an increase in weight loss over 36 days. Together these data support the continued development of GS-4571 into the clinic as a novel orally bioavailable GLP-1R small molecule agonist.

Disclosure

J. Vogel: None. M. Seung: None. B. Marchand: Employee; Gilead Sciences, Inc. Stock/Shareholder; Gilead Sciences, Inc., Pfizer Inc., Arrowhead Pharmaceuticals, Inc., Kronos Bio, Inc., Allogene Therapeutics, Inc., AbCellera Biologics Inc., Arbutus Biopharma Corporation. N. Bhangre: Employee; Gilead Sciences, Inc. Research Support; Gilead Sciences, Inc. Stock/Shareholder; Gilead Sciences, Inc. J. Mukherjee: None. S.E. Ammann: Employee; Gilead Sciences, Inc. M. Armstrong: Employee; Gilead Sciences, Inc. G. Brizgys: Employee; Gilead Sciences, Inc. E. Chin: Employee; Gilead Sciences, Inc. C. Chou: None. J. Cottell: Employee; Gilead Sciences, Inc. S.D. Schroeder: Employee; Gilead Sciences, Inc. R. Thomas-Tran: Employee; Gilead Sciences, Inc. Z. Yang: None. M. Peters: Employee; Gilead Sciences, Inc. G. Budas: Employee; Gilead Sciences, Inc. M.L. Mitchell: Employee; Gilead Sciences, Inc. M. Chojnacka: None. S. Jermain: None. J. Hung: Employee; Gilead Sciences, Inc. S. Kulkarni: None. Q. Yue: None. D.W. Lin: Employee; Gilead Sciences, Inc. D.A. Miranda: None.
163-OR: RNAseq Analysis Reveals Temporal Dynamics of Colonic Immune Response to High-Fat Diet in Mice
Authors: KELLER LENA , BOSCH ANGELA J. , LOW ANDY J.Y. , CAVELTI-WEDER CLAUDIA
Published: June 2024

Introduction & Objective: We previously showed that 1 week of high-fat diet (HFD) increases pro-inflammatory colonic macrophages (Mϕ) and that their depletion was associated with improved glycemic control. The current study aimed to elucidate the temporal changes of gene expression of intestinal immune cells in mice fed a HFD compared to chow.

Methods: Male C57BL/6N mice were fed either a HFD or chow for 1 week or 3 months. GTTs assessed the metabolic status. Colon CD45+ cells were isolated, subjected to single-cell RNA sequencing (analyzed by the Bioinformatics Core Facility), and used for flow cytometry analysis. Rectal inhibition of the cGAS-STING pathway was performed using H-151 (STING inhibitor). To compare chow with HFD, an unpaired Mann-Whitney U test with a two-sided distribution was done.

Results: After 1 week of HFD, glucose tolerance was impaired, and pro-inflammatory Mϕ of the colon increased, which were no longer elevated after 3 months of HFD. ScRNA-seq revealed an early increase in T-cells, which remained after 3 months, while B cells were only increased and activated after 3 months of HFD. Enrichment analysis showed an increased IFN-γ and IFN-α response in monocytes (Mono) and Mϕ after 1 week of HFD, while after 3 months EMT and ROS pathways were downregulated. Pseudo-bulk RNA-seq unveiled an upregulation of the cGAS-STING pathway within Mono and Mϕ after 1 week of HFD, which was no longer present after 3 months. Local STING inhibition for 1 week led to improved glucose tolerance and downregulation of IFN-α gene expression in the colon but did not protect against the increase of inflammatory Mϕ upon HFD.

Conclusion: 1 week of HFD resulted in profound changes in the immune cell landscape of the colon with an early innate and late adaptive immune response upon HFD feeding. The cGAS-STING pathway was upregulated early after initiation of the HFD, suggesting its initiating role in the disease. Indeed, interfering with the cGAS-STING pathway led to improved glycemia in HFD-fed mice.

Disclosure

L. Keller: None. A.J. Bosch: None. A.J.Y. Low: None. C. Cavelti-Weder: None.

Funding

The Swiss National Science Foundation (SNSF) Grant number 32003B_204937 / 2
168-OR: Perilipin 2 Regulates Fatty Acid Trafficking to Mitochondria through Microlipophagy in Beta Cells
Authors: LIU SIMING , JOGLEKAR ADITYA , FRESHLY AIDAN , PEACHEE SPENCER , WIPF ISRAEL J. , BOVEE CORINNE , VIKRAM ANAMIKA , GIEDT MICHELLE , FINK BRIAN , SIVITZ WILLIAM , ANKRUM JAMES A. , TOOTLE TINA , IMAI YUMI
Published: June 2024

Perilipin 2 (PLIN2) is the major structural protein of triglycerides (TG) storing lipid droplets (LD) and increased in lipid loaded and type 2 diabetic pancreatic beta cells. PLIN2 is protective for beta cells since its knockdown increases fatty acid (FA) flux to mitochondria and impairs mitochondrial function. Here, we addressed a pathway by which PLIN2 deficiency compromises mitochondrial integrity in beta cells. When the incorporation of Bodipy C12 (C12, a fluorescent long chain FA analog) into organelles was followed in INS1 cells over 8 h, C12 incorporation into LD was seen in both control and shPLIN2 cells during the first hour indicating that PLIN2 downregulation does not affect the initial triglycerides (TG) synthesis and its incorporation into LD. C12 started to accumulate into mitochondria after 4 to 8 h only in shPLIN2 cells indicating that FA transfer to mitochondria occurs after LD formation under PLIN2 deficiency. Treatment with a lysosomal lipase inhibitor Lali2 increased TG level and prevented C12 transfer into mitochondria in shPLIN2 cells, indicating that lysosomal degradation of LD precedes FA transfer to mitochondria. Microlipophagy appears to mediate LD degradation in shPLIN2 cells since a macroautophagy blocker 3MA did not prevent FA flux to mitochondria. Importantly, Lali2 rescued mitochondrial fragmentation (p<0.05 vs DMSO control) and glucose-stimulated insulin secretion (p<0.05) in shPLIN2 INS1 cells. Mitochondrial fragmentation and its rescue by Lali2 were also seen in shPLIN2 treated human beta cells (p<0.05). As for a mechanism mediating FA transfer to mitochondria, the direct contact between lysosome and mitochondria was increased (p<0.01) before FA flux to mitochondria occurs in shPLIN2 cells. Collectively, PLIN2 deficiency in beta cells impairs mitochondrial integrity through lysosomal TG degradation followed by FA delivery to mitochondria. These data highlight the importance of regulation of microlipophagy by PLIN2 for beta cell function.

Disclosure

S. Liu: None. A. Joglekar: None. A. Freshly: None. S. Peachee: None. I.J. Wipf: None. C. Bovee: None. A. Vikram: None. M. Giedt: None. B. Fink: None. W. Sivitz: None. J.A. Ankrum: None. T. Tootle: None. Y. Imai: None.

Funding

R01 DK090490 (NIH) I01 BX005107 (VA)
1683-P: Characteristics of Lifestyle, Dietary Nutrients, and Gut Microbiota Associated with Predisease State of Metabolic Syndrome in Japanese Adults
Authors: WATANABE YOSHIYUKI , FUJISAKA SHIHO , HONOKI HISAE , KADO TOMONOBU , NISHIMURA AYUMI , BILAL MUHAMMAD , RAHIL ASLAM MUHAMMAD , IGARASHI YOSHIKO , MORINAGA YOSHITOMO , TOBE KAZUYUKI
Published: June 2024

Introduction/Objective: Environmental factors such as lifestyle, diet, and associated changes in the gut microbiota are the most important determinants of obesity. Recently, we investigated the relationship among metabolic parameters, lifestyle habits, and fecal 16S rRNA seq data of Japanese healthy adults. These parameters are intricately and closely related, and we identified two microbes that can prevent metabolic syndrome (ADA 83rd scientific sessions). In this study, we further expanded this cohort study to examine lifestyle habits, nutrient intake, and microbial species associated with visceral obesity (VO).

Methods: A total of 435 participants who underwent annual health check in 2019 were enrolled, provided data on metabolic parameters, and completed a lifestyle questionnaire including a dietary record of the previous three days. Fecal 16S rRNA seq data were obtained from 38 participants in 2022 and analyzed along with the changes in body weight from 2019.

Results: The average age, body mass index, and HbA1c were 40.5±9.7, 24.0±4.1 kg/m2 and 5.5±0.37%, respectively. VO was clearly associated with metabolic parameters. There was a significant positive correlation between VO and lifestyle habits such as smoking, eating speed, irregular meal time, and frequency of fried food intake. Regarding nutrient composition, intake of resistant starch, β-carotene, maltose, and sorbitol were negatively correlated with waist circumference, while intake of caffeine and tannins were positively correlated. Furthermore, significant differences depending on weight changes were observed in the microbial species such as increased Bifidobacterium adolescentis and Prevotella stercorea in subjects who lost weight compared to those who gained weight.

Conclusion: Lifestyle, diet intake, and characteristic changes in the microbiota are associated with VO in healthy adults prior to onset of metabolic syndrome.

Disclosure

Y. Watanabe: None. S. Fujisaka: None. H. Honoki: None. T. Kado: None. A. Nishimura: None. M. Bilal: None. M. Aslam: None. Y. Igarashi: None. Y. Morinaga: None. K. Tobe: None.

Funding

Japan Society for the Promotion of Science (JSPS) KAKENHI (20K08882, 21K20896 and 22K16424); AMED PRIME (JP18gm6010023h0001); Lotte Foundation; Yakult Bio-Science Foundation; First Bank of Toyama Scholarship Foundation; Japan Diabetes Foundation; Japan Society for the Study of Obesity (JASSO); Yamaguchi Endocrine Resarch Foundation and Hokugin Young Researcher Grant
1712-P: DOC2b Enrichment Mitigates Cytokine-Induced CXCL10 Expression via Attenuating IKK-NFkB and STAT-1 Signaling in Beta Cells
Authors: CHATTERJEE BHOWMICK DITI , AHN MIWON , BHATTACHARYA SUPRIYO , THURMOND DEBBIE C.
Published: June 2024

Introduction & Objective: The reduction of beta-cell dysfunction, and demise hold promise for therapeutic intervention for type 1 diabetes. Previously, we have reported the beneficial role of SNARE-regulatory protein DOC2b in preventing cytokine-induced beta-cell stress and apoptosis. However, the underlying mechanism remains unknown. We hypothesize that DOC2b enrichment mitigates cytokine-induced beta-cell apoptosis via attenuating CXCL10 signaling.

Methods: To test the hypothesis, we have used RNA-seq, qPCR, proteomics, biochemical studies, and immuno-confocal microscopy using DOC2b-enriched or -depleted primary islets (human and mouse) and clonal beta-cells challenged with or without proinflammatory cytokines.

Results: Human islet RNAseq analysis revealed a significant decline in NFkB signaling pathway in islets with DOC2b enrichment vs control. Our proteomics and co-immunoprecipitation studies identified IKK, NFkB p65 and STAT-1 as binding partners of DOC2b in clonal beta-cells. Western blot studies demonstrated that DOC2b enrichment corresponds with a significant reduction in total and activated levels of IKK, NFkB p65 and STAT-1 proteins in cytokine-stressed human islets. Immunofluorescent confocal microscopy showed DOC2b enriched cytokine-stressed clonal beta-cells to harbor reduced levels of NFkB p65 in the nucleus. In beta-cells, cytokine-induced chemokine ligand CXCL10 expression is known to be regulated via upstream NFkB p65 and STAT-1 mediated signaling. Intriguingly, qPCR and western blot studies revealed marked attenuation of cytokine-induced CXCL10 levels in DOC2b-enriched human islets and clonal beta-cells; by contrast, CXCL10 is elevated in DOC2b-depleted beta cells and mouse islets.

Conclusion: These data support a model in which DOC2b protects beta-cells from cytokine stress and apoptosis via attenuation of IKK-NFkB and STAT-1 signaling, thereby reducing CXCL10 expression.

Disclosure

D. Chatterjee Bhowmick: None. M. Ahn: None. S. Bhattacharya: None. D.C. Thurmond: Consultant; Truebindings.

Funding

JDRF Postdoctoral fellowship (3-PDF-2020-934-A-N); Diabetes Research Connection grant National Institutes of Health (DK067912, DK112917, and DK102233)
1745-P: IPO13 Maintains Glucose Homeostasis by Regulating Insulin Secretion and α-Cell Expansion
Authors: ZHAO QINYING , YANG YING , JI SHUHUI , CHEN YUANSI , FENG WENLI , LIU MING
Published: June 2024

Introduction & Objective: Importin 13 (IPO13) is a member of IPOβ family and is one of only three mammalian IPO proteins able to mediate both import and export of cargo proteins. IPO13 contributes to brain and eye development, however the role of IPO13 in β cell function and glucose homeostasis remains unknown. Herein, we performed a new β cell-specific IPO13 knockout (IPO13-βKO) mouse model to investigate the β cell function changes caused by IPO13 deficiency.

Methods: Body weight, fasting blood glucose, and plasma insulin levels was tested weekly to observe the glucose homeostasis of IPO13-βKO mice. Insulin or glucagon gene expression, proinsulin processing, and insulin or glucagon content were detected. Isolated islets insulin and glucagon secretion ability was measured by glucose-stimulated insulin secretion test. Transcriptome analysis of associated genes GO term were used to understand the related gene changes.

Results: IPO13 was downregulated in β cells of diabetic db/db mice and high-fat fed mice, revealing a possible role of IPO13 in β-cell function. IPO13-βKO caused severe early-onset, insulin-deficient diabetes. Functional studies revealed the decreased expression of prohormone convertase 1/3 and carboxypeptidase E, and increased abnormal insulin granules, resulting in the decreased insulin production. Islet transcriptome analysis showed decreased expression of genes associated with β-cell maturation. Multiple experiments confirmed that, although IPO13 deletion decreased insulin, the expansion of α cells and elevated glucagon levels, especially after glucose stimulation. Importantly, IPO13 deficiency decreased expression of β-cell function-related genes, including Glut2, Cask, and Syt7, contributing to impaired islet glucose-stimulated insulin secretion (GSIS).

Conclusion: Our study not only reveal a critical role of IPO13 in the regulation of insulin secretion and α cell expansion but also provide insight into the mechanism of diabetes caused by IPO13 deficiency.

Disclosure

Q. Zhao: None. Y. Yang: None. S. Ji: None. Y. Chen: None. W. Feng: None. M. Liu: None.

Funding

National Natural Science Foundation of China (82220108014,81830025); National Key R&D Program of China (2022YFE0131400, 2019YFA0802502); Key project of Tianjin Municipal Health Commission (TJWJ2021ZD001); Tianjin Key Medical Discipline (Specialty) Construction Project (TJYXZDXK-030A); Tianjin Medical University General Hospital Clinical Research Program (22ZYYLCZD02).
1777-LB: Time Below Range Is Correlated with Level 2 (L2) Hypoglycemia Event Rates in Type 1 Diabetes—Results from DCLP3, DIAMOND, and WISDM Trials
Authors: LIGGINS RICHARD , CALHOUN PETER , PEERS SUSAN , RIDDELL MICHAEL C. , BECK ROY W.
Published: June 2024

Background: Minimizing CGM time below range (TBR; T<70 and T<54 mg/dL), is an important therapeutic goal with clinical targets in diabetes (≤4% and ≤1%, respectively). TBR is valuable for clinical management of hypoglycemia, but individual symptomatic episodes are also important to patients. Clinical trials report both TBR and hypoglycemia events (glucose <54 mg/dL for ≥15 min), but associations between the two have not been quantified. The purpose of this work is to compare the associations of TBR with L2 hypoglycemia event rates.

Methods: The relationship between hypoglycemic events and T<70 or T<54 was assessed for cohorts using real-time CGM or SMBG with interval use blinded CGM in 3 trials: DCLP3, DIAMOND, and WISDM. CGM metrics and CGM-detected event rates were calculated over a 6-month period.

Results: There was a strong correlation between hypoglycemic event rates and T<70 or T<54 (R = 0.91-0.93 for CGM and SMBG users). 70 CGM users exceeding the T<70 target (28%) had mean of 3.1 L2 events/week. 85 SMBG users exceeding the T<70 target (59%) had mean 4.1 events/week. Similar trends were seen for the T<54 target. Those meeting T<70 target had on average <1 L2 event/week (CGM: 0.9; SMBG: 0.8 events/week).

Conclusion: TBR was highly correlated with hypoglycemia event rates and participants not meeting hypoglycemic clinical targets had frequent L2 hypoglycemic events.

Disclosure

R. Liggins: Employee; Zucara Therapeutics. Stock/Shareholder; Zucara Therapeutics. P. Calhoun: None. S. Peers: Employee; Zucara Therapeutics. M.C. Riddell: Consultant; Eli Lilly and Company. Speaker's Bureau; Novo Nordisk. Advisory Panel; Supersapiens. Consultant; Dexcom, Inc. Speaker's Bureau; Sanofi. Advisory Panel; Zealand Pharma A/S. Speaker's Bureau; Dexcom, Inc. Stock/Shareholder; Zucara Therapeutics. R.W. Beck: Consultant; Insulet Corporation. Research Support; Insulet Corporation. Consultant; Tandem Diabetes Care, Inc. Research Support; Tandem Diabetes Care, Inc. Consultant; Beta Bionics, Inc. Research Support; Beta Bionics, Inc., Dexcom, Inc., Bigfoot Biomedical, Inc. Consultant; Novo Nordisk. Research Support; Novo Nordisk, Eli Lilly and Company. Consultant; embecta, Vertex Pharmaceuticals Incorporated, Hagar, Ypsomed AG, Sanofi, Zucara Therapeutics, Sequel.
1784-LB: LRP5 Promotes Fatty Acid Oxidation through Enhancement of PPAR/PGC-1 Signaling in DKD with Dyslipidemia
Authors: HE XUEMIN , ZHANG RUI , WEN SIYING , XIANG XIAOXIN , CAI MENGYIN , CHEN YANMING
Published: June 2024

Dyslipidemia is an independent risk factor for diabetic kidney disease (DKD), but some lipid-lowering drugs are reported to exacerbate this disease, as they prohibit fatty acid oxidation (FAO) which is the primary energy source in renal proximal tubules. In this study, we demonstrated low-density lipoprotein receptor-related protein 5 (LRP5) as a novel regulator of both systemic lipid metabolism and FAO in the kidney. In Lrp5-deficient mice fed with a high-fat diet, the levels of serum lipids were significantly up-regulated, accompanied by worsened tubulointerstitial fibrosis and loss of renal tubular epithelial cells. By overexpression and knockdown of LRP5 in renal proximal epithelial cells, LRP5 was proven to be essential for maintaining the epithelial phenotype under the condition of lipotoxicity. RNA-sequencing suggested that Lrp5 deficiency greatly promoted lipid deposition but compromised the FAO in the DKD kidneys. Further analysis identified that LRP5 potentiated the activation of peroxisome proliferator-activated receptor (PPAR)/PPARgamma coactivator 1 signaling, restoring the compromised FAO in the renal proximal tubules of DKD. These results highlight a potential therapeutic role of LRP5 in promoting systemic lipid metabolism and FAO for treating DKD with dyslipidemia.

Disclosure

X. He: None. R. Zhang: None. S. Wen: None. X. Xiang: None. M. Cai: None. Y. Chen: None.

Funding

Grants from the Municipal Science and Technology Planning Projects of Guangzhou City (SL2023A03J00003), National Natural Science Foundation of China (82270886, 82000782), Sci-Tech Research Development Program of Guangzhou City (202201020589), Key Area R&D Program of Guangdong Province (2019B020227003)