bluuebunny/crossref_metadata_2025 huggingface dataset:
177-OR: Worsening Insulin Resistance Is Key Pathological Contributor to Dysglycemia in Lean Koreans—A Longitudinal Validation Study in the Korean Genome and Epidemiology Study (KoGES)
Authors: KIM DOOHWA , KIM JINMI , IM MYUNGSOO , RYANG SOREE , YI WOOK , KIM MINSOO , JIN KIM YEONG , JOO KIM IN , JIN KIM YOUNG , KANG HYUK , SHERMAN ARTHUR , CHUNG STEPHANIE T. , SOO KIM SANG , HA JOON
Published: June 2023

Insulin resistance (IR) is a modest but important pathophysiological factor in the development of type 2 diabetes (T2D) in East Asians and manageable through lifestyle intervention. The degree to which worsening insulin resistance independent of beta cell dysfunction, contributes to diabetes progression in lean Koreans is unknown. With a 10-year longitudinal study from a Korean cohort, we investigated whether worsening insulin resistance contributes to disease progression in individuals who had normal glucose tolerance at baseline (N=3700, Age=50.1±8.3 y, BMI= 24.1±2.9 kg/m2). We identified metabolic characteristics of progressors and non-progressors to prediabetes (PreDM) or T2D at baseline and 10 year-longitudinal changes in IR and BMI. To assess whether longitudinal changes of IR, independent of beta-cell function (BCF), contributed to progression, the cohort was divided into low and high BCF groups, using group median at baseline. Progressors to PreDM or T2D had weaker BCF and more insulin resistance, compared to non-progressors (Panel A) at baseline. Insulin sensitivity declined more, 30.7 vs 46.5 vs 16.7% and BMI increased in progressors to PreDM or T2D, but not in nonprogressor (Panels A and B). Conclusion: Worsening insulin resistance even for lean people is a key pathological factor to PreDM and T2D progression.

Disclosure

D.Kim: None. H.Kang: None. A.Sherman: None. S.T.Chung: None. S.Kim: None. J.Ha: None. J.Kim: None. M.Im: None. S.Ryang: None. W.Yi: None. M.Kim: None. Y.Kim: None. I.Kim: None. Y.Kim: None.

Funding

Busan Economic Promotion Agency; National Research Foundation of Korea (2022H1D3A2A01063552); Korea Health Industry Development Institute (HI18C2383); dkNET New Investigator Pilot Program in Bioinformatics; National Institute of Diabetes and Digestive and Kidney Diseases
1777-P: Three-Dimensional Imaging Reveals Pancreatic Islet Fast Calcium Wave Origin Formation
Authors: YU YI
Published: June 2023

Pulsatile insulin secretion triggered by global calcium waves within pancreatic β cells is essential to blood glucose homeostasis. The calcium wave propagation forms by gap junction coupling among beta cells, but the emergence of wave origins is still unclear. We developed a 3D islet calcium imaging system and adapted data processing methods to observe and analyze islet calcium wave propagation quantitatively. A global fast-traveling calcium wave identifies in all kinds of oscillation modes. The calcium waves could initiate by multiple conserved β-cell clusters. We showed that the beta cell subpopulation, which first responded to high glucose stimulation, would partially contribute to calcium wave origin formation. To determine whether the spatial distribution of alpha or delta cells affects wave origin formation, we developed transgenetic mice that all islet cells were directly labeled with GCaMP6f, and alpha cells or delta cells were marked with tdTomato by Cre-Loxp strategy. Our data suggested that delta cells in the periphery modulated wave origins by electrical coupling and inhibitory paracrine interaction. Population oscillator models based on natural islet 3D structures reproduce the wave propagation observed in experiments. Interestingly, 3D imaging showed only local calcium wave bursts in ob/ob mice islets, and Immunofluorescence staining showed those sporadic bursts also correlated to delta cells.

Disclosure

Y.Yu: None.
1782-P: Perinatal Hypoxia Lowers the Glucose Threshold for Insulin Secretion Causing Hypoglycemia and Hyperinsulinism
Authors: JULIANA CHRISTINE , DE LEON DIVA
Published: June 2023

Perinatal stress-induced hyperinsulinism is a common cause of persistent hypoglycemia in at-risk neonates. The hypoxia-inducible factor-1 (HIF-1) pathway regulates cellular adaptation in hypoxic conditions through hypoxia response elements. We hypothesize that perinatal hypoxia leads to activation of the HIF1 pathway causing increased insulin secretion from neonatal β-cells. We examined glucose homeostasis and insulin secretion in NeuroD1-Cre;VhlLoxp/Loxp(VhlbetaKO) and in hypoxic wild type (WT) mouse pups in the first week of life. In VhlbetaKO pups postnatal day 8 (P8), plasma glucose was significantly lower compared to littermate controls (76 vs 129 mg/dL). Plasma insulin (0.54 vs 0.27 ng/mL) and the insulin to glucose ratio were significantly greater in VhlbetaKO pups indicating a failure to suppress insulin secretion. VhlbetaKO islet perifusion showed the lower plasma glucose level was due to a lower threshold (5 mM) for glucose stimulated insulin secretion (GSIS) compared to controls (10 mM). To assess the consequences of perinatal hypoxia, we exposed WT mouse pups to hypoxia (10% O2) between embryonic day 18 and P6. Islets from the hypoxia exposed pups had a lower GSIS threshold (3 mM) compared to islets from normoxic pups (5 mM) at P6. Hypoxic islets also had a lower insulin secretion threshold when stimulated with BCH, a glutamate dehydrogenase activator, or tolbutamide, a KATP channel inhibitor, suggesting that HIF1 pathway activation leads to a decreased stimulus threshold for secretion at or distal to the KATP channel. Patch clamps revealed that β-cells from hypoxic pups were more depolarized than normoxic controls. Our results show that the HIF1 pathway is critical for setting the GSIS threshold and a potential mediator of PSHI. We posit perinatal hypoxia and the HIF1 pathway at the core of β-cell maturational defects leading to increased risk of diabetes in adult life and the long-sought answer to the cause of perinatal stress-induced hyperinsulinism.

Disclosure

C.Juliana: Research Support; Crinetics Pharmaceuticals, Inc., Twist Bioscience, AmideBio. D.De leon: Consultant; Zealand Pharma A/S, Crinetics Pharmaceuticals, Inc., Eiger BioPharmaceuticals, Hanmi Pharm. Co., Ltd., Research Support; Ultragenix, Crinetics Pharmaceuticals, Inc., Hanmi Pharm. Co., Ltd., Rezolute, Inc.
188-LB: Association between Age at Diagnosis of Type 2 Diabetes and Hospitalization for Heart Failure (HHF)
Authors: KE CALVIN , SHAH BAIJU R. , ECHOUFFO TCHEUGUI JUSTIN
Published: June 2023

Background: The relation between age at T2D diagnosis and HHF is unclear. We conducted a population-based cohort study to examine the association between age at diagnosis of T2D and incident HHF in Ontario, Canada.

Methods: Using administrative health databases, we identified people with new-onset T2D between April 1, 2005 and March 31, 2015. We matched each person to 3 other people without diabetes according to birth year and sex. We excluded any people with prior HHF. We used Cox proportional hazards models to estimate adjusted hazard ratios (HR) for the association between age at T2D diagnosis and incident HHF (followed up until March 31, 2020).

Results: Among 743,053 individuals with T2D and 2,199,539 matches, 126,241 incident HHF events occurred (median follow-up 8.9 years). T2D was associated with a greater adjusted hazard of HHF at younger ages (e.g., HR at age 30 years: 5.71, 95% CI: 5.46-5.96; Figure: Model 1) than at older ages (e.g., HR at age 60 years: 2.51, 2.46-2.55). Additional adjustment for recognized mediators (hypertension, coronary artery disease, chronic kidney disease) marginally attenuated this relation (Figure: Model 2).

Conclusion: Younger age at T2D diagnosis is independently associated with a disproportionately elevated risk of HHF relative to age-matched individuals without T2D. This relation may be substantially mediated by novel mechanisms that are inadequately understood.

Disclosure

C. Ke: Advisory Panel; Sanofi, Speaker's Bureau; AstraZeneca, Abbott. B. R. Shah: None. J. Echouffo tcheugui: None.

Funding

National Heart, Lung, and Blood Institute (K23HL153774 to J.E.T.); University of Toronto (to B.R.S.)
19-OR: Monitoring Stage 2 to Stage 3 Transition in Type 1 Diabetes Using Continuous Glucose Monitoring (CGM)
Authors: FROHNERT BRIGITTE I. , SEPULVEDA FLOR , STOUGHTON JESSICA E. , STECK ANDREA , SIMMONS KIMBER M.
Published: June 2023

Introduction: CGM can be used to monitor evolution of dysglycemia in presymptomatic, stage 2 type 1 diabetes (T1D) and to target early initiation of insulin upon reaching stage 3 T1D.

Methods: Participants (N=31) with dysglycemia by A1c, OGTT, CGM and/or home glucose testing (HGT) measures (Table 1) were randomized 2:1 into 6 months unblinded CGM-guided education intervention vs blinded CGM and monitoring only. Surveys included PHQ8, PedsQLFamilyImpact, Tolerance of Uncertainty and Diabetes Knowledge (30 point scale).

Results: Intervention and control group were similar in baseline characteristics (Table), except younger age and significantly higher 2-hour OGTT glucose level in the intervention group. Diabetes knowledge was not significantly different between intervention and control at baseline (22±6 vs 20±7, p=0.61) or 3-month follow-up (23±6 vs 20±4, p=0.28). There were no differences between groups for PHQ8, PedsQLFamilyImpact or Tolerance of Uncertainty at baseline or follow-up to date. Of those diagnosed with stage 3 T1D, CGM average sensor glucose and time >140 mg/dL were higher than at study entry. All participants met ADA stage 3 diagnostic criteria; however, none had A1c≥6.5%.

Conclusion: CGM facilitates early recognition of stage 3 T1D before elevation in HbA1c and metabolic decompensation. Unblinded CGM does not appear to negatively impact quality of life.

Disclosure

B.I.Frohnert: Advisory Panel; Provention Bio, Inc. F.Sepulveda: None. J.E.Stoughton: None. A.Steck: None. K.M.Simmons: Advisory Panel; Provention Bio, Inc., Consultant; Dexcom, Inc., Provention Bio, Inc., Research Support; Novartis.

Funding

The Leona M. and Harry B. Helmsley Charitable Trust (G-1911-03463)
190-OR: Lrtm1, a Novel Regulator of Insulin Signaling and Metabolism
Authors: WANG GUOXIAO , YU YINGYING , CHEN WENQIANG , CAI WEIKANG , LIU XIANGYU , RONALD KAHN C.
Published: June 2023

Patients with obesity and metabolic syndrome, as well as individuals with pre-type 2 diabetes, exhibit hyperinsulinemia prior to development of hyperglycemia due to underlying skeletal muscle insulin resistance. To mimic the effect of chronic hyperstimulation of the insulin receptor (IR), we overexpressed the IR specifically in skeletal muscle (IRMOE). This led to skeletal muscle post-receptor desensitization, with increased IR and IRS-1(Tyr) phosphorylation but decreased phosphorylation of Akt Ser473 and Thr308. To identify the regulators involved in this post-receptor insulin resistance, we performed RNA sequencing of IRMOE muscle. Among the most upregulated genes was Lrtm1, a poorly characterized leucine rich repeat transmembrane molecule while highly expressed in the heart and skeletal muscle. Overexpression of Lrtm1 in C2C12 myoblasts led to increased phosphorylation of early insulin signaling molecules (the insulin receptor, IRS-1, and Shc), but reduced phosphorylation of the downstream molecules Akt (at both Ser473 and Thr308) and Erk Thr202/204 following insulin stimulation. Mice with knockout of Lrtm1 (Lrtm1KO) showed significant increases in percent lean mass and decreases in percent fat mass, as well as a slight reduction in overall body weight. In addition, Lrtm1KO mice were more active than controls in both metabolic cages and an open field behavioral tests. Lrtm1KO mice also exhibited improved glucose tolerance and insulin sensitivity, especially in males, even on normal chow diet. Most importantly, Lrtm1KO mice were protected from high fat diet induced obesity and metabolic syndrome, with the knockouts showing 18% less body weight gain, 30% lower fat mass, significantly improved glucose tolerance and improved insulin sensitivity. Thus, Lrtm1 is a novel regulator of post-receptor insulin signaling and glucose metabolism that may provide a new target for therapy insulin resistant prediabetes and type 2 diabetes.

Disclosure

G. Wang: Employee; Agilent. Y. Yu: None. W. Chen: None. W. Cai: None. X. Liu: None. C. Kahn: None.
192-LB: Temporal Relationship of New Pediatric Diabetes Diagnoses and COVID-19
Authors: REDDY NEHA , JOHNSON STEVE , MOFFITT RICHARD A. , EVANS MICHAEL , YEH HSIN-CHIEH , REUSCH JANE E.B. , WONG RACHEL , BUSE JOHN B. , BRAMANTE CAROLYN , HARPER JEREMY
Published: June 2023

SARS-CoV-2 infection may increase the incidence of diabetes mellitus (DM) in children.1-3 Mechanisms are incompletely understood and likely vary between type 1 and type 2 DM. All children may be at greater risk regardless of infection due to pandemic control measures increasing sedentary time and disrupting primary care.4,5 This cross sectional analysis examined the percentage of new DM diagnoses in children across 60-day calendar-time intervals relative to SARS-CoV-2 infection in a nationwide database, the National COVID Cohort Collaborative. The percentage of new type 1 and 2 DM diagnoses was highest in the acute period, within 60 days of infection. After acute infection, the percentage of new diagnoses appears lower than pre-infection percentages. Further study of this nuanced relationship is needed to inform screening and treatment.

Disclosure

N. Reddy: None. J. Harper: None. S. Johnson: None. R. A. Moffitt: None. M. Evans: None. H. Yeh: None. J. E. B. Reusch: Advisory Panel; Medtronic. R. Wong: None. J. B. Buse: Consultant; Alkahest, Anji Pharmaceuticals, AstraZeneca, Bayer Inc., Biomea Fusion, Inc., Boehringer Ingelheim International GmbH, CeQur SA, Cirius Therapeutics, Inc., Corcept Therapeutics, Eli Lilly and Company, GentiBio, Glycadia, Glyscend Inc., Janssen Pharmaceuticals, Inc., Mellitus Health, Pendulum Therapeutics, Praetego, LLC, Stability Health, Terns, Inc, Valo, Other Relationship; Novo Nordisk, Research Support; Dexcom, Inc., Novo Nordisk, vTv Therapeutics, Stock/Shareholder; Glyscend Inc., Mellitus Health, Pendulum Therapeutics, PhaseBio Pharmaceuticals, Inc., Praetego, LLC, Stability Health. C. Bramante: None.

Funding

National Center for Advancing Translational Sciences (U24TR002306); Clinical and Translational Science Institute, University of Minnesota (UL1TR002494); National Institute of Diabetes and Digestive and Kidney Diseases (K23DK124654); National Institutes of Health (3R01DK130351-02S1)
193-OR: Muscle α-Parvin Deletion Results in Insulin Resistance by Impairing GLUT4 Translocation and Hexokinase II Association with Mitochondria in Mice
Authors: CAPPEL DAVID A. , DEAVER JOHN W. , COZZANI LUCIANO , BRACY DEANNA , LANTIER LOUISE , DONG XINYU , PRINTZ RICHARD , ZENT ROY , POZZI AMBRA , WASSERMAN DAVID H.
Published: June 2023

Genetic deletions of specific integrin receptor a-subunits and the integrin-like kinase (ILK) have no effect on insulin action in lean C57Bl/6J mice but are required for insulin resistance in diet-induced obese (DIO) mice. ILK binds to a-parvin through which it controls the rho kinase pathway and cytoskeleton thereby altering cellular compartmentation and dynamics. The hypothesis tested was that integrin signaling is required for insulin resistance in DIO mice due to disruption of the critical interaction between ILK and a-parvin. We predicted that preventing this interaction in lean mice would recapitulate the insulin resistance observed in DIO mice. Lean and DIO mice with muscle-specific a-parvin (mPar) knockout (KO) and wild type littermates (WT) were studied. Insulin clamps were performed in mPar KO and WT mice. A muscle-specific index of glucose uptake (Rg) was measured isotopically during insulin clamps. Lean mPar KO had a 50% reduction in muscle Rg that was associated with a similar deficit in GLUT4 translocation to the cell membrane and a decrease in hexokinase II-associated with mitochondria. Mitochondria oxidative capacity was reduced by 50% in lean mPar KO mice compared to lean WT mice. The insulin resistance in DIO WT mice was no worse in DIO mPar KO mice. Insulin signaling was not impaired by mPar KO in lean mice. However, lean mPar KO had impaired a-actinin, Rac1, p-cofilin/cofilin, and p-MLC/MLC compared to lean WT mice during insulin stimulation. These changes affect cytoskeletal dynamics and provide a basis for the reduction in GLUT4 translocation, hexokinase II localization to mitochondria, and impaired mitochondria oxidation. In conclusion, a-parvin is a key node in coupling integrin signaling as it causes muscle insulin resistance in otherwise healthy lean mice. Deletion of muscle a-parvin does not affect insulin signaling but rather attenuates insulin-stimulated glucose uptake by impairing cytoskeletal dynamics.

Disclosure

D.A.Cappel: None. D.H.Wasserman: None. J.W.Deaver: None. L.Cozzani: None. D.Bracy: None. L.Lantier: None. X.Dong: None. R.Printz: None. R.Zent: None. A.Pozzi: None.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (R01DK050277, R01DK054902, R24DK059637)
194-OR: Lower Insulin Sensitivity before the Onset of Type 2 Diabetes Is Associated with Increased Risk of Albuminuria after Diabetes Onset
Authors: WILLIG MEEAH R. , STINSON EMMA J. , LOOKER HELEN C. , MITCHELL CASSIE M. , HANSON ROBERT L. , NELSON ROBERT G. , KRAKOFF JONATHAN , CHANG DOUGLAS C.
Published: June 2023

Background: Reduced renal insulin signaling is implicated in the pathogenesis of albuminuria, a marker of kidney failure, cardiovascular disease, and mortality. We sought to investigate whether insulin action and secretion, measured prior to diabetes onset, are associated with development of albuminuria after diabetes onset.

Methods: Baseline body composition, insulin sensitivity by hyperinsulinemic-euglycemic clamp at submaximal and max insulin stimulation (240 and 2400 pmol/m2/min; M-low and M-high), and insulin secretion by intravenous glucose tolerance test (acute insulin response, AIR) were measured in 166 Indigenous American adults who subsequently developed diabetes. After diabetes onset and during median follow-up of 12.3 years, 44 participants (27%) developed albuminuria. The separate associations of M-low, M-high, and AIR (per 1-SD change) with risk of albuminuria (urine albumin-to-creatinine ratio ≥30 mg/g) were identified by Cox regression models adjusted for age, sex, and body fat (%).

Results: Participants who developed albuminuria were of similar age (26.8 ± 5.6 vs. 27.1 ± 6.0 years), sex distribution (50% vs. 46% male), body fat (36.6 ± 6.0 vs. 35.8 ± 8.0%), and AIR (3.1 ± 0.3 vs. 3.0 ± 0.3, pmol/L [log]) as those who did not develop albuminuria, but had lower insulin sensitivity (M-low: 0.32 ± 0.06 vs. 0.36 ± 0.11, p = 0.007, M-high: 0.85 ± 0.11 vs. 0.90 ± 0.12, p = 0.03; mg/kg-metabolic body size/min [log]). In separate adjusted models, lower M-low and M-high (i.e., lower insulin sensitivity) were both associated with increased risk for albuminuria (HR 1.67, 95% CI 1.12, 2.50, p = 0.01; HR 1.35, 95% CI 1.03, 1.79, p = 0.03), whereas AIR was not (HR 1.18, 95% CI 0.79, 1.75, p = 0.42).

Conclusion: Lower insulin sensitivity is associated with development of albuminuria, suggesting a role for insulin signaling in the pathogenesis of proteinuria and is a potential therapeutic target for prevention of cardiovascular and kidney disease.

Disclosure

M.R.Willig: None. E.J.Stinson: None. H.C.Looker: None. C.M.Mitchell: None. R.L.Hanson: None. R.G.Nelson: None. J.Krakoff: None. D.C.Chang: None.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (DK069015-36)
196-LB: Heterogeneity in Elevated Glucose and A1C as Predictors of the Prediabetes-to-Diabetes Transition—Framingham Heart Study, Multiethnic Study on Atherosclerosis, Jackson Heart Study, and Atherosclerosis Risk In Communities
Authors: PATEL CHIRAG
Published: June 2023

The clinical utility of the elevated altered glucose tolerance and prediabetes, and novel phenotypes of diabetes risk is a hotly debated. The heterogeneity of risk and incidence across diverse cohorts needs to be considered when developing new approaches for screening and when communicating the uncertainty in the transition rate. How the definition of prediabetes relates to cohort-level sources of variation and predicts the transition from prediabetes to overt diabetes has not been well characterized. Here, we study the range and heterogeneity in the absolute incidence and the relative risk for diabetes across competing definitions of prediabetes in participants from four large US cohorts, the Framingham Heart Study (FHS), Multi-Ethnic Study on Atherosclerosis (MESA), Jackson Heart Study (JHS), and Atherosclerosis Risk in Communities (ARIC). We computed the incidence rates across prediabetes (fasting glucose, A1C%; ADA or WHO), outcome definition (elevated glucose or overt T2D), body mass index, blood pressure, age, race, sex and cohort. The cross-cohort meta-analytic estimate rate for transition to diabetes for FBG 100-125 mg/dL, 110-125 mg/dL, and A1C 5.7-6.4% were 4.2, 8.2, 2.8 cases per 100 person-years, respectively. This contrasts with incidence rates of 0.6, 1.0, and 0.6 for the individuals with FBG less than 100, FBG less than 110, and A1C% less than 5.7% respectively. All the meta-analytic estimates had I2 greater than 93%. The between-cohort range FBG 110-125 mg/dL was 4 (FHS Generation 3), 5 (FHS Generation 2), 5.5 (ARIC), 12.5 (JHS), and 14.8 (MESA). In contrast, the range of the incidence rate for A1C 5.7-6.4% was 1.6 (ARIC) to 5.2 (JHS). We found that these inter-cohort differences cannot be explained by body mass index or ethnic differences and reporting of rates need to consider the wide prediction interval between cohorts.

Disclosure

C. Patel: None.

Funding

National Institutes of Health (R01ES032470)
197-OR: Dynorphin, a Novel Paracrine Factor That Regulates Insulin Secretion
Authors: BLANDINO-ROSANO MANUEL , PANZER JULIA , BERNAL-MIZRACHI ERNESTO
Published: June 2023

Within the pancreatic islet, the crosstalk between different islet cells through paracrine signals orchestrates a hormonal response that controls glucose levels. The dysregulation of these signals contributes to impaired glucose homeostasis and diabetes. Therefore, understanding intra-islet communication is imperative for developing new strategies for diabetes management. Here, we show that intra-islet dynorphin (Dyn) stimulates somatostatin (SST) secretion and is a novel factor regulating islet function and insulin secretion in human and mouse islets. Dyn, an opioid peptide involved in stress response, pain, and addiction is synthesized in human and mouse β-cells and secreted in response to glucose. Dyn acts mainly through the k-opioid receptor (KOR) expressed in all islet cells with the highest expression in δ-cells. Using perifusion and static incubation studies, we show that Dyn induces SST secretion and decreases insulin secretion in mouse and human islets and that Dyn fails to induce SST secretion in islets from mice with KOR deletion in δ-cells, thereby providing a mechanism for feedback control of insulin secretion (β- to δ-cell Dyn/KOR negative feedback loop). Our data also show that Dyn is increased in islets from HFD-fed mice (8-fold) and in human β-cells from T2D donors. Remarkably, dynorphin mRNA is one of the top ten most upregulated genes in islets from HFD-fed mice, higher than several critical β-cell genes, including pdx1 or ucn3. We demonstrate that the β- to δ-cell Dyn/KOR negative feedback loop is upregulated in diabetes and pharmacological inhibition or genetic deletion of KOR in δ-cells improves glucose homeostasis in high-fat diet (HFD)-fed mice, demonstrating the therapeutic potential of this system. The novel role of the Dyn/KOR axis in islet function in healthy and diabetogenic conditions can have profound implications for glucose homeostasis and serve to develop potential targets for T2D.

Disclosure

M.Blandino-rosano: None. J.Panzer: None. E.Bernal-mizrachi: None.
198-OR: Pancreatic Elastase Regulates Human Beta-Cell Viability by Impairing the PAR2 Pathway
Authors: BASILE GIORGIO , VETERE AMEDEO , HU JIANG , DE JESUS DARIO F. , CHOUDHARY AMIT , WAGNER BRIDGET , KULKARNI ROHIT
Published: June 2023

The discovery of SerpinB1 pointed to acinar cell-derived proteases such as pancreatic elastase (PE) being involved in regulating human β-cell viability. Indeed, we observed that expression of a major form of PE, namely CELA3B, was increased in acinar cells from donors with type 2 diabetes (T2D) compared to samples from nondiabetic (ND) donors. Surprisingly, CELA3B protein levels were higher in T2D vs. ND islets, although its gene expression levels were virtually undetectable. We confirmed that increasing doses of exogenous PE is able to decrease viability and function of EndoC-βH3 (βH3) cells in vitro. To evaluate the effects of PE inhibition on β-cell survival, we used telaprevir, an FDA-approved drug, that we identified as a potent PE blocker using a High-Throughput Screening assays with an IC50 of 15.6 nM to inhibit PE activity. Consistent with the effects of SerpinB1 on β-cells, telaprevir also increased human β-cell viability in in vitro and in vivo systems. By performing phospho-antibody microarrays and single-cell RNA-Seq in human islets treated with vehicle or telaprevir, we identified the Protease-Activated Receptor 2 (PAR2) pathway as a candidate pathway linking PE inhibition to β-cell viability. We validated the results by treating EndoC-βH1 (βH1) cells with a PAR2 inactivating peptide (FSLLRY-NH2) in addition to PE +/- telaprevir. We observed that PE impaired the PAR2 cascade, and these effects were reversed by telaprevir in control β-cells, but not in cells treated with the PAR2 inhibitor. Furthermore, telaprevir was able to reverse PE effects and improve viability of control human primary β-cells, but not of those in which the PAR2 pathway was pharmacologically impaired. These data point to novel pathways reflecting acinar-β-cell crosstalk that has therapeutic potential to resolve diabetes in patients.

Disclosure

G. Basile: None. A. Vetere: None. J. Hu: None. D.F. De Jesus: None. A. Choudhary: None. B. Wagner: Research Support; Novo Nordisk. Stock/Shareholder; Pfizer Inc., Provention Bio, Inc. Research Support; Japan Tobacco Inc. Advisory Panel; Novo Nordisk. Research Support; Ono Pharmaceutical Co., Ltd. Stock/Shareholder; Curis, Inc. Consultant; Fresh Tracks Therapeutics. R. Kulkarni: Advisory Panel; Novo Nordisk, Inversago. Research Support; Inversago. Advisory Panel; Biomea Fusion, Inc., REDD Pharma.
2-LB: Effect of Somatostatin Receptor 2 Antagonism (SSTR2a) on Oral Glucose Tolerance (OGT) in a Rat Model of Type 2 Diabetes (T2D)
Authors: D'SOUZA NINOSCHKA C. , ALEALI NADIA , SHAKERI DORSA , HOFFMAN EMILY G. , ATHERLEY SARA C. , CHAMPSI SABRINA , EL-ZAHED MAYA , LIGGINS RICHARD , CHAN OWEN , RIDDELL MICHAEL C.
Published: June 2023

Background: Hypoglycemia remains a concern for insulin-treated individuals living with diabetes. SSTR2a increases the endogenous glucagon counterregulatory response during hypoglycemia in rodent models of diabetes, but its impact on OGT is unclear. We examined the impact of SSTR2a on OGT in a rodent model of T2D maintained on basal insulin therapy.

Methods: High fat fed (HFF), low dose streptozotocin (35 mg/kg) T2D rats received SSTR2a treatment (ZT-01 3 mg/kg) or vehicle (N=8-9/group) immediately before a fasted OGT test (OGTT, 2 g/kg). Glycemia, glucagon and c-peptide levels were measured pre- and post-dose and monitored for 120 minutes.

Results: The OGTT resulted in comparable rises in blood glucose levels in both groups, consistent with an animal model of T2D. Glucagon levels rose within 15 minutes of SSTR2a and glucose administration (120 ± 70 vs 4.8 ± 3, p=0.006) and remained higher than controls for the duration of the OGTT. C-peptide levels also increased from baseline by 116 ± 77% in SSTR2a-treated animals compared to 28.9 ± 70% in controls.

Conclusion: SSTR2a treatment increases glucagon and c-peptide levels following oral glucose ingestion in this rat model of T2D. These preliminary findings suggest that the use of the SSTR2a should not adversely impact glucose control around meals if used as a preventive therapy against insulin-induced hypoglycemia.

Disclosure

N. C. D'souza: None. M. C. Riddell: Advisory Panel; Zealand Pharma A/S, Zucara Therapeutics, Indigo Diabetes, Consultant; Lilly Diabetes, Eli Lilly and Company, Jaeb Center for Health Research, Speaker's Bureau; Dexcom, Inc., Novo Nordisk, Sanofi, Stock/Shareholder; Supersapiens, Zucara Therapeutics. N. Aleali: None. D. Shakeri: None. E. G. Hoffman: None. S. C. Atherley: None. S. Champsi: None. M. El-zahed: None. R. Liggins: Employee; Zucara Therapeutics, Stock/Shareholder; Zucara Therapeutics. O. Chan: None.

Funding

GlycoNet (CD-85)
201-LB: Benefit of Dual Therapy with GLP-1 RA and SGLT2i on Renal Outcomes in Type 2 Diabetes
Authors: ZAREINI BOCHRA , GERDS THOMAS A. , SØRENSEN KATHRINE K. , CLEMMENSEN KIM K.B. , KVIST KAJSA , DAVID JENS-PETER , TORP-PEDERSEN CHRISTIAN
Published: June 2023

Background: There is increased use of dual glucagon like peptide-1 receptor agonist (GLP-1 RA) and sodium-glucose co-transporter-2 inhibitor (SGLT2i) therapy, but real-world evidence on the renal benefit is lacking.

Aim: To compare the dual use of GLP-1 RA and SGLT2i to other dual second-line type 2 diabetes therapies with respect to renal outcomes.

Methods: From 2010-2021 patients from the Danish nationwide registries were followed from start of dual second-line type 2 diabetes treatment. Outcomes were chronic renal disease, end-stage renal disease and >50% eGFR decrease from baseline. The estimated risk following 1 of 4 dual therapy combinations was determined using a longitudinal causal inference framework assuming all patients followed one dual therapy for 5 years.

Results: In total 87,201 persons were included (GLP-1 RA and SGLT2i: 14,831, GLP-1 RA and DPP4/SU/TZD: 20,417, SGLT2i and DPP4/SU/TZD: 22,803, dual DPP4/SU/TZD: 29,150). The 5-year risk ratio (95%CI) of dual GLP-1 RA and SGLT2i therapy compared to reference (dual DPP4/SU/TZD) for chronic renal disease: 1.03 (0.97;1.08), end-stage renal disease: 0.12 (0.09;0.15) and >50% decrease in eGFR: 0.52 (0.45;0.59).

Conclusion: Dual therapy with GLP-1 RA and SGLT2i compared to other dual therapies results in greater risk reduction of end-stage renal disease and eGFR decline, while dual SGLT2i and DPP4/SU/TZD showed greater risk reduction of chronic renal disease.

Disclosure

B. Zareini: None. T. A. Gerds: None. K. K. Sørensen: None. K. K. Clemmensen: Employee; Novo Nordisk A/S, Stock/Shareholder; Novo Nordisk A/S. K. Kvist: Employee; Novo Nordisk A/S. J. David: Employee; Novo Nordisk A/S, Sanofi. C. Torp-pedersen: Research Support; Novo Nordisk, Bayer Inc.
203-OR: Features of Human Th-Like Regulatory T Cells in the Pathogenesis of Type 1 Diabetes
Authors: QIN YAO , LI YUXIAO , DAI LIUYAN , WEI QIANYING , HUANG MEI , ZHANG MEI
Published: June 2023

Background: The imbalance between Tregs, Bregs and proinflammatory Th cells plays a vital role in the pathogenesis and development of T1D. Accumulating evidence has revealed that Treg has phenotypic plastic changes into other subsets under pathological conditions. However, whether Tregs convert into other immune cell types in T1D and the potential influencing factors remain unknown. This study aimed to examine the changes of Th-like Tregs in T1D patients and determine whether Th cells and IL-10+ Bregs play roles in Treg polarization.

Methods: A total of 49 T1D patients and 20 healthy controls (HC) were recruited in this study. Flow cytometry was used to measure Treg plasticity (including CD4+Foxp3+IFN-γ+ Th1-like, CD4+Foxp3+IL-4+ Th2-like and CD4+Foxp3+IL-17+ Th17-like Tregs), the proportion of CD27+CD39hi Bregs, and Th cell subsets (including Th1, Th2 and Th17 cells) in the peripheral blood. Cytokines were detected by ELISA.

Results: The frequencies of Th1-like Tregs and Th17-like Tregs in T1D were lower than those in HC, while the proportion of Th17 cells was significantly increased in T1D. The frequency of Bregs was markedly higher in T1D relative to HC, but IL-10 expression of Bregs was reduced. Interestingly, compared with lean and overweight patients, Th1-like Tregs were higher in patients with normal weight, but Treg plasticity was not affected by disease status (age at diagnosis, islet autoantibodies and β-cell function) or T1D risk loci (rs3118470 or rs2104286) in IL2RA. Additionally, positive correlations between Th1-like Tregs and Th17-like Tregs and between Bregs and Th2-like Tregs were observed in T1D. Meanwhile, the frequency of Th1-like Tregs was negatively related to IL-6 and the frequency of Th2-like Tregs was negatively associated with TNF-α.

Conclusion: Our results firstly explored the features of human Th-like Tregs in the pathogenesis in T1D, which might contribute to improve our understanding of the pathogenic mechanisms of T1D.

Disclosure

Y.Qin: None. Y.Li: None. L.Dai: None. Q.Wei: None. M.Huang: None. M.Zhang: None.

Funding

National Natural Science Foundation of China (81974103, 82000747)
214-LB: Plasma Proteomic Markers of Iron and Risk of Diabetes in a Biracial Cohort
Authors: CONWAY REBECCA B. , YOUNG KENDRA , PRATTE KATHERINE A. , KINNEY GREGORY L. , AUSTIN ERIN , LI YISHA , BOWLER RUSSEL , MCCLAIN DONALD A. , CRAPPO JAMES
Published: June 2023

Higher levels of iron have been linked to increased diabetes risk among European and European American (EA) populations; whether this is true for other populations where anemia is more common is unknown. Ferritin is an iron storage protein linked to diabetes risk; transferrin transports catalytic iron, reducing its oxidative damage. We tested whether proteomic measurements of ferritin and transferrin were associated with diabetes risk in a biracial cohort of current and former smokers. EA and African American (AA) participants from the COPDGene Cohort who were free of diabetes (n=4,671) at study baseline were followed for the incidence of diabetes. The Somascan was used on plasma measured at followup to determine relative amounts of proteins among participants. Logistic regression was used to calculate OR (95% CIs) of the cross-sectional relationship of natural log transformed ferritin and transferrin with diabetes risk. During an average of 5.6 years of follow-up, the incidence of diabetes was 7.9%. Ferritin was associated with increased diabetes risk (OR=1.29, 1.04-1.61), while higher transferrin linked with decreased risk (OR=0.19, 0.06-0.56) controlling for age, sex, BMI, hepcidin and smoking. When stratified by race, increased risk was associated with higher ferritin only among AA (OR=1.46, 1.07-2.01) and not for EA (OR=1.11, 0.81-1.52). Stratification by sex revealed that the relationship of ferritin was similar among AA men and women and EA women, with non-significant ORs ranging from 1.49-1.55; but null association among EA men (OR = 1.00, 0.65-1.52). Similarly, ORs for transferrin non-significantly ranged from 0.24-0.29 for AA men and women and EA women, but for EA men there was a significant 93% decreased risk for each natural long increase in transferrin (OR=0.07, 0.001-0.60). Our data suggest that higher body iron stores, as measured by ferritin, increases diabetes risk among both AA and EA. Ferritin may be a better marker for AA men and women and EA women while transferrin is a better marker for EU men.

Disclosure

R. B. Conway: None. K. Young: None. K. A. Pratte: None. G. L. Kinney: None. E. Austin: None. Y. Li: None. R. Bowler: None. D. A. Mcclain: None. J. Crappo: None.

Funding

National Heart, Lung, and Blood Institute (U01HL089897, U01HL089856); AstraZeneca; Bayer Pharmaceuticals; Boehringer Ingelheim; Genentech; GlaxoSmithKline; Novartis; Pfizer Inc.; Sunovion
217-LB: Heterogeneity of Single Cells Obtained from Peripheral Blood Mononuclear Cells Collected from Youth with Recent-Onset Type 1 Diabetes
Authors: WU WENTING , PARKS-SCHENCK CORINNE , GUO TINGBO , ZHANG CHI , MIRMIRA RAGHAVENDRA G. , EVANS-MOLINA CARMELLA
Published: June 2023

Whole blood bulk RNA sequencing has been used to guide T1D clinical trial design and assess response to disease modifying interventions, whereas it is with limited information about cell specific gene expression changes. Here, we aimed to apply computational strategies to deconvolute cell type composition using cell specific gene expression references. Single-cell RNA sequencing (scRNA-seq) was conducted to profile 108,795 peripheral blood mononuclear cells obtained from 5 youth within 48 hrs of Stage 3 T1D onset (avg age 11.4; 3M;2F) and 5 age- and sex-matched controls and identified 31 distinct cell clusters. In T1D, the proportion of CD4+ T central memory (TCM) cells was increased (P = 0.018), while plasmacytoid dendritic cells (pDC), platelets, and hematopoietic stem and progenitor cells (HSPC) proportions were reduced (P = 0.021, 0.012 and 0.017 respectively) compared to controls. The most robust transcriptomic changes were observed in CD14+ and CD16+ monocyte populations and CD1C+ conventional type-2 dendritic (cDC2) cells. Using this scRNA-seq reference dataset, we ran computational algorithms CIBERSORTx and our in-house reference-free method ICTD to deconvolute cell proportions using public clinical trial data testing the anti-CD20 monoclonal antibody rituximab (n=37) vs. placebo (n=17). Strong correlation was observed between the methods for cell proportion estimates (P < 2.2*10-16). It showed that B cell subsets were reduced by rituximab. At baseline, non-responders had a higher proportion of CD8+ T cells (P = 0.04), and responders had higher proportions of neutrophils (P =0.04). These data suggest that deconvolution approaches can be utilized for secondary analysis of existing clinical trial bulk RNA-seq data, to link cell specific immune signatures associated with drug responder status.

Disclosure

W. Wu: None. C. Parks-schenck: None. T. Guo: None. C. Zhang: None. R. G. Mirmira: None. C. Evans-molina: Advisory Panel; Provention Bio, Inc., DiogenX, Avotres Inc., Neurodon, MaiCell Therapeutics, Other Relationship; Isla Technology, Bristol-Myers Squibb Company, Nimbus Therapeutics, Research Support; Lilly, Astellas Pharma Inc.

Funding

dkNET; Indiana University Center for Diabetes and Metabolic Diseases; National Institutes of Health (U01DK127786)
219-OR: Glucagon Counterregulation in a Hypoglycemic Clamp in Type 1 Diabetes Is Increased by ZT-01, a Novel Somatostatin Receptor 2 Antagonist—A Phase 1b Study
Authors: ABITBOL ALEXANDER , PEERS SUSAN , SIMONSON ERIC , MIDMER MICHAEL , RIDDELL MICHAEL , LIGGINS RICHARD
Published: June 2023

This study evaluated the effect of ZT-01 on glucagon counterregulation during hypoglycemia in adults with type 1 diabetes, in a Phase 1b randomized, three-arm, double-blind crossover trial in 23 hypoglycemia aware adults with T1D. Participants underwent three hypoglycemic clamp procedures with 3 or 20 mg ZT-01 or placebo dosed 1 h prior to stepwise glucose clamp conditions using variable rate IV insulin infusion: euglycemia (5.0 ± 0.5 mmol/L), level 1 (3.5 ± 0.3 mmol/L, L1), and level 2 hypoglycemia (2.6 ± 0.2 mmol/L, L2).

With ZT-01, peak glucagon increased by up to 15.1 ± 10.5 and 27.1 ± 17.3 pg/mL, in L1 and L2 hypoglycemia, respectively, compared with no increase in L1 and an 8.4 ± 8.4 pg/mL increase in L2 hypoglycemia with placebo (p<0.0001, figure). A counterregulatory response of increased glucose level coinciding with an increased glucagon level was observed more frequently with ZT-01 than placebo. No clinically significant effects on other counterregulatory hormones or hypoglycemia symptom scores were observed with ZT-01. A transient rise in glucagon and blood glucose was observed with ZT-01 post-dose prior to hypoglycemia. No SAEs were reported and no TEAEs were observed with ZT-01.

This study demonstrates proof-of-concept that ZT-01 significantly enhances the defective counterregulatory response in people with T1D during L1 and L2 hypoglycemia.

Disclosure

A.Abitbol: Advisory Panel; Abbott Diabetes, Lilly Diabetes, Dexcom, Inc., Novo Nordisk Canada Inc., Janssen Pharmaceuticals, Inc., Research Support; Abbott Diabetes, Lilly Diabetes, Zucara Therapeutics, Novo Nordisk Canada Inc., Moderna, Inc., Senseonics, Speaker's Bureau; Boehringer Ingelheim (Canada) Ltd., Lilly Diabetes, Amgen Canada, Dexcom, Inc., Novo Nordisk Canada Inc., HLS Therapeutics Inc., Janssen Pharmaceuticals, Inc., Merck & Co., Inc., Sanofi. S.Peers: Employee; Zucara Therapeutics. E.Simonson: None. M.Midmer: Board Member; Zucara Therapeutics, Employee; Zucara Therapeutics, Stock/Shareholder; Zucara Therapeutics. M.Riddell: Advisory Panel; Zealand Pharma A/S, Zucara Therapeutics, Indigo Diabetes, Consultant; Lilly Diabetes, Eli Lilly and Company, Jaeb Center for Health Research, Speaker's Bureau; Dexcom, Inc., Novo Nordisk, Sanofi, Stock/Shareholder; Supersapiens, Zucara Therapeutics. R.Liggins: Employee; Zucara Therapeutics, Stock/Shareholder; Zucara Therapeutics.
22-LB: MiRNA Profiling of Exosomes Derived from Perivascular Adipocyte Tissue in Type 2 Diabetic Mice
Authors: CHEN SHUZHEN , POLAKI VENKATA , BIHL JI , WANG JINJU
Published: June 2023

Background: Exosomes (EXs), a major type of extracellular vesicles, are emerging as a novel type of intercellular communicators. MicroRNAs (miRs) are one of the major executors of EXs. The previous study shows that lean and obesity adipocyte tissue EXs could elicit different effects in response to insulin sensitivity, the underlying mechanism is related to their carried miRs. Given EX cargoes and function vary on their cellular status, we speculate the miR profiling of EXs derived from the perivascular adipose tissue (PVAT) is altered in diabetic conditions.

Methods: EXs were isolated from the PVAT tissue of type 2 diabetic db/db and control db/c mice. EX size and concentration were analyzed by nanoparticle tracking analysis. The miR profiling of PVAT-EXs was analyzed by mmu-miR miRome profiling kit. The miRs of interest were further validated by qRT-PCR.

Results: 1) The PVAT-EXs level was higher in diabetic db/db mice than that in non-diabetic db/c mice; 2) In db/db mice, exosomal miRs profile was changed. The exosomal miRs, miR-223, miR-181a, miR-146a, miR-34a, and miR-210, were either down-regulated or up-regulated > 3-fold when comparing that in db/c mice. Among these candidate miRs, miR-181a, miR-223, miR-210, and miR-146a might be involved in modulating adipose tissue inflammation and/or vascular function. MiR-34a could participate in white adipose tissue browning, macrophage polarization, and glucose tolerance. Conclusion: Our data have demonstrated that the miR profiling of PVAT-derived EXs is changed in type 2 diabetic conditions, which suggests the functions of these EXs might be altered in diabetic conditions.

Disclosure

S. Chen: None. V. Polaki: None. J. Bihl: None. J. Wang: None.
22-OR: High Glucose Metabolism Fuels Cathepsin L Maturation to Promote SARS-CoV-2 Infection in Patients with Diabetes
Authors: ZHAO MIAOMIAO , HE QIONG , YANG JIN-KUI
Published: June 2023

Patients with diabetes are more likely to develop severe COVID-19 and deaths. However, the underlying mechanism remains poorly understood. Previously, we identified a widely expressed lysosome protease Cathepsin L (CTSL) promotes SARS-CoV-2 infection and may be a promising drug target (PMID: 33774649, 35668062). Here, we show that patients with diabetes have elevated CTSL concentration and activity in patients with or without COVID-19. The CTSL levels are positively correlated with HbA1c in humans. Hyperglycemic clamp study suggests that high glucose increases CTSL activity in healthy individuals. In vitro, we find that high glucose, but not high insulin, level promotes SARS-CoV-2 infection in wildtype (WT) cells. However, these promoting effects are largely reduced in CTSL-knockout (KO) cells. By using lung tissues from healthy, diabetic patients, WT and db/db mice, we find diabetes promotes CTSL maturation. Further, we identify that high glucose level, but not high insulin level, promotes CTSL activity. The matured CTSL levels are significantly increased in diabetic tissues. High glucose promotes CTSL translocation from the endoplasmic reticulum (ER) to lysosome through the ER-Golgi-lysosome axis (Fig.1). Our study reports the biological and potential clinical significance of glucose metabolism in CTSL maturation to promotes SARS-CoV-2 infection in patients with diabetes.

Disclosure

M.Zhao: None. Q.He: None. J.Yang: None.

Funding

National Natural Science Foundation of China (81930019)
221-OR: Retrospective Review of Genetic Mutations and Treatments in Patients with Monogenic Diabetes of the Youth (MODY)
Authors: DENG LILY , SHAH AMY S. , KRISHNAMURTHY MANSA
Published: June 2023

Monogenic diabetes results from specific genetic mutations that result in diabetes mellitus. Clinical phenotypes differ based on the genetic defect, and treatment options are driven by the underlying genetic cause. Thus, accurate genetic diagnosis and evaluation of response to treatment is essential. Retrospective chart review was utilized to identify patients with MODY at a single institution who had confirmed genetic mutations. Demographics, co-morbidities, initial islet cell autoantibodies, diagnosis and treatment, and current treatments were evaluated. Patients diagnosed with MODY (n=92) comprised of 3% of the total patient population diagnosed with diabetes (78% T1DM, 19% T2DM) between 2000 to present day. For patients with MODY, the average age of diabetes diagnosis was 10.3 years and their mean HgbA1c was 8.0% at diagnosis. Three and a half percent of patients with MODY had ketoacidosis at diagnosis and 6.7% had positive islet cell autoantibodies. Among patients with MODY, the most common gene mutations were HNF1A, GCK, and HNF1B. Novel genetic mutations in PDX1, RFX6, BLK and KFL11 were also identified. Current treatment modalities of patients with MODY were compared (insulin, Metformin, Sulfonylureas, Metformin-Glyburide, insulin-Metformin, GLP-1 receptor agonists). For each medication, reduction in HgbA1c was seen at follow-up (0.05-1.15% reduction). All medications except for insulin and Metformin-Glyburide demonstrated a reduction in BMI at follow-up. The greatest reduction in BMI was observed in patients on GLP-1 receptor agonists and insulin-Metformin (3.3% and 8.89% respectively). Our study highlights the importance of genetic testing in patients who present with diabetes without ketoacidosis and that testing positive for islet antibodies does not preclude patients from a MODY diagnosis. Moreover, future investigation of GLP-1 receptor agonist as a treatment for MODY patients is warranted.

Disclosure

L.Deng: None. A.S.Shah: None. M.Krishnamurthy: None.