bluuebunny/crossref_metadata_2025 huggingface dataset:
1676-P: A Novel GLP1R/GCGR Dual Agonist, DA-1726 Elicits Weight Loss Superior to Semaglutide in Diet-Induced Obese Rats
Authors: CHAE YUNA , KIM TAE-HYOUNG , JUNG IL-HUN , HEON KIM HYUNG , KIM MI-KYUNG
Published: June 2023

DA-1726 showed superior weight loss efficacy compared to Semaglutide (SEMA) in DIO mice. In this following study, a dose-response of DA-1726 was evaluated to determine the maximum efficacy in DIO rats that are known to have good translatability to human studies. The half-life of DA-1726 was longer in rats compared to mice, however the in vitro activity of DA-1726 against rat glucagon receptor was less potent than in the mouse, and plasma protein binding was approximately 10-fold higher in rats. Therefore, we set the effective dose for rats higher than for mice. DA-1726 was injected twice a week for about 4 weeks, a dose-dependent and significant weight loss effect was observed. The minimum effective dose in DIO rats was found to be 250 nmol/kg. Then, the maximum body weight loss effects of DA-1726 (500 and 1000 nmole/kg) and SEMA were compared in the DIO rat. In this study, DA-1726 showed an excellent weight loss effect than SEMA (32.6% for DA-1726 at a high dose vs. 24.0% for SEMA, p<0.05). The low-dose DA-1726 group showed a similar effect compared to SEMA even though they consumed more food. The high-dose DA-1726 group showed similar food intake as SEMA, but led to a higher weight loss effect. After repeated dosing, the high-dose DA-1726 significantly increased the expression of energy metabolism-related genes (Ucp1, Ppargc1a) in white adipose tissues (WAT), supporting increased energy expenditure. So then, in order to confirm whether this increased gene change was a direct effect leading to weight loss or an indirect effect caused by weight loss, we assessed the changes in gene expression after single dosing. DA-1726 (250 and 500 nmol/kg) induced small but significant weight loss 3 days after a single injection (-7.6% and -9.5% vs. control). However, the genes expression (Ucp1, Ppargc1a) in WAT was significantly increased only in the 500 nmol/kg-treated group suggesting a direct effect. Therefore, DA-1726 is expected to elicit excellent weight loss effects in humans with a new mechanism.

Disclosure

Y.Chae: None. T.Kim: None. I.Jung: None. H.Kim: None. M.Kim: Employee; Dong-A ST.
1693-P: Association of Sleep and OSA Severity with Neurocognitive Function in the RISE Study
Authors: TEMPLE KARLA A. , TJADEN ASHLEY H. , EHRMANN DAVID , MANCHANDA SHALINI , EDELSTEIN SHARON , HANNON TAMARA S. , CRAFT SUZANNE , MOKHLESI BABAK ,   RISE CONSORTIUM
Published: June 2023

Poor sleep and obstructive sleep apnea (OSA) have both been associated with worsening neurocognitive function. In the Restoring Insulin Secretion (RISE) Study, we assessed the relationship between presence and severity of OSA and cognition in treatment-naïve adults (n=179) with prediabetes or early T2D. A cognitive battery (CogState™ and story recall) assessed 1) psychomotor speed; 2) visual pattern separation; 3) visual attention and working memory; and 4) verbal learning and episodic memory. Wrist accelerometers worn for 7 days measured average sleep duration and efficiency. Other sleep outcomes were measured during one night of laboratory polysomnography. Linear regression models were fit to assess independent relationships between cognition and sleep measures. The cohort consisted of 44% females, 56% males; 53% white, 33% black, 6% Hispanic; age 54.7±8.9 years and BMI 34.7±5.4 kg/m2 (mean±SD). Based on ADA criteria, 73% had prediabetes and 27% had T2D. Sleep duration was 6.5±1.0 h; sleep efficiency was 85.9±7.5%; 26% had moderate OSA, 40% had severe OSA. After adjustment for age, sex, race/ethnicity, education, and BMI, higher sleep efficiency was associated with better visual pattern separation (as measured by the One Card Learning Test; p=0.039) but not with any other neurocognitive assessment. In the RISE cohort, measures of OSA severity (apnea-hypopnea index, oxygen desaturation index, sleep duration below 90% oxygen saturation, microarousal index) were not associated with baseline cognition. This cross-sectional analysis shows a high prevalence of moderate/severe OSA in treatment-naïve adults with prediabetes or early T2D. Although higher sleep efficiency was associated with better visual pattern separation, it was not associated with other measures of cognitive function. Further, OSA severity was not associated with measures of neurocognition.

Disclosure

K.A.Temple: None. A.H.Tjaden: None. D.Ehrmann: None. S.Manchanda: Advisory Panel; Inspire. S.Edelstein: None. T.S.Hannon: Advisory Panel; Eli Lilly and Company. S.Craft: None. B.Mokhlesi: None. Rise consortium: n/a.

Funding

American Diabetes Association (1-20-RISE-01 to S.E.); National Institute of Diabetes and Digestive and Kidney Diseases; National Heart, Lung, and Blood Institute; U.S. Department of Veterans Affairs; Kaiser Permanente Southern California
1711-P: Assessment of Prediabetes in Patients with Morbid Obesity (MO)
Authors: BRIX JOHANNA , PARZER VERENA , HUBER SIMONE L. , LUDVIK BERNHARD
Published: June 2023

The frequency of prediabetes as well as the optimal method to identify glucose abnormalities in morbid obesity (MO) is subject to debate. We, therefore, evaluated the frequency of prediabetes and the optimal method for its respective diagnosis in a large cohort with MO.

We included 1.626 patients with MO (age 34±10 years, BMI 44.6± 7.0 kg/m², 74.3% women). All patients without overt type 2 diabetes (T2D) underwent a 75g OGTT. Prediabetes was diagnosed according to ADA criteria. Demographic, cardiovascular risk-markers, insulin levels and renal parameters were assessed.

We excluded 421 (25.9%) patients due to T2D. Regarding prediabetes, 339 patients (28.1%) fulfilled the fasting glucose criterion, 240 the 2-hour postprandial criterion (19.9%), and 594 patients the HbA1c criterion (49.2%). 56 patients (4.6%) fulfilled all three criteria, 810 (67.2%) had at least one criterion. 933 (77.4%) patients fulfilled either the fasting glucose or the HbA1c criterion, and 834 (69.2%) either the 2h postprandial or HbA1c criterion. Patient's characteristics are depicted in table 1.

The results of our study suggest that fasting glucose or HbA1c are sufficient to diagnose prediabetes. This is particularly of interest since postoperative changes in gut anatomy following bariatric surgery might render a postoperative OGTT invalid for follow-up, whereas fasting glucose or HbA1c are not affected.

Disclosure

J.Brix: Advisory Panel; Boehringer Ingelheim Pharma GmbH&Co.KG, Eli Lilly and Company, Novo Nordisk, Speaker's Bureau; AstraZeneca, Eli Lilly and Company, Novo Nordisk. V.Parzer: None. S.L.Huber: None. B.Ludvik: Advisory Panel; Eli Lilly and Company, Novo Nordisk, Boehringer Ingelheim Pharma GmbH&Co.KG, Amgen Inc., AstraZeneca, Research Support; Eli Lilly and Company, Novo Nordisk, Boehringer Ingelheim Pharma GmbH&Co.KG, Amgen Inc., AstraZeneca, Speaker's Bureau; Eli Lilly and Company, Novo Nordisk, Boehringer Ingelheim Pharma GmbH&Co.KG, Amgen Inc., AstraZeneca.
1740-P: Regulation of Endocrine Cell Alternative Splicing Revealed by Single-Cell RNA Sequencing in Type 2 Diabetes
Authors: WANG JIN , WEN SHIYI , CHEN MINQI , XIE JIAYI , SHI GUOJUN
Published: June 2023

The prevalent RNA alternative splicing (AS) underlies molecular diversity, which has been demonstrated in regulating cellular functions and diseases. However, the contribution of AS in pancreatic islets remains unclear during diabetes progression. Here, we reanalyzed the full-length single-cell RNA sequencing data from the deposited database to investigate AS regulation across human pancreatic endocrine cell types in nondiabetic (ND) and type 2 diabetes (T2D) individuals. Our analysis demonstrated the significant association between AS profiles and cell-type-specificity, which could be applied to distinguish the clustering of major endocrine cell types. Moreover, AS profiles were enabled to clearly define the mature subset of β-cells in healthy controls, which was completely lost in T2D. Further analysis revealed that RNA-binding proteins (RBPs), hnRNPs and FXR1 family proteins were predicted to induce the functional impairment of β-cells through regulating AS profiles. Finally, trajectory analysis of endocrine cells suggested the β-cell identity shift through dedifferentiation and transdifferentiation of β-cells during the progression of T2D. Together, our study provides a new mechanism for regulating β-cell functions and suggests the significant contribution of AS program during diabetes.

Disclosure

J. Wang: None. S. Wen: None. M. Chen: None. J. Xie: None. G. Shi: None.
1760-P: Mining Animal Venoms as a Source of Insulinotropic Peptides for Potential Diabetes Therapy
Authors: HUI JIN NG NATASHA , YEOW KOH CHO , CHING CARMEN , GOPALAKRISHNAKONE PONNAMPALAM , TEO ADRIAN
Published: June 2023

T2D development and progression is widely known to be caused by pancreatic beta cell dysfunction, whether in the presence or absence of insulin resistance. There are however limited diabetes drugs that directly target the beta cell. Hence, there is a need to discover yet untapped pathways to increase or rescue beta cell function. Animal venoms provide a rich resource of bioactive compounds, many of which are highly potent and selective. Venom peptides have been harnessed for therapeutic drug development, such as the blockbuster diabetes drug, exenatide, a GLP-1 receptor agonist, being a synthetic form of exendin-4 that was first isolated from the saliva of the Gila monster. We hypothesize that we can further discover and develop new therapeutic agents that promote pancreatic beta cell function based on venom-derived compounds. We studied up to seven animal venoms from snakes, bees and scorpions. Pancreatic beta cells (including EndoC-βH1 cells, human islets, and MIN6 cells) were treated with crude animal venoms from each species and evaluated for insulin secretion capacity. We used a range of doses that elicit insulin secretion without causing cellular damage. Venoms from Apis mellifera (honey bee) and Naja naja (Indian cobra) were shown to robustly stimulate insulin secretion in a dose-dependent manner without affecting cell viability. Treatment with these venoms were also able to rescue diabetic cell models. We prioritized these two venoms for fractionation via gel filtration and reverse phase HPLC. After subsequent screening of the venom sub-fractions in insulin secretion assays, we pinpointed specific sub-fractions responsible for stimulating insulin release. Ongoing work is in progress to identify and validate selected peptides for insulinotropic activity, safety and stability. The insulinotropic peptides (and any modifications) may represent new therapeutic strategies for tackling T2D in future.

Disclosure

N.Ng: Stock/Shareholder; BetaLife. C.Koh: None. C.Ching: None. P.Gopalakrishnakone: None. A.Teo: None.

Funding

A*STAR Career Development Fund (202D800020)
1764-P: Assessing Gene Expression Profile and Insulin Secretion in Human Beta Cells (EndoC-BH3) under Glucose Exposure
Authors: MULLER YUNHUA L. , WIEDRICH KIMBERLY , SUTHERLAND JEFF , JONES DARTANYON , BAIER LESLIE
Published: June 2023

Maternal diabetes is a risk factor for type 2 diabetes in the offspring, and in utero exposure to high glucose has been shown to affect pancreatic beta cell development in animal models. However, the developmental stage and specific genes which underlie these effects in humans are unknown. We aimed to understand the consequences of high glucose on the fetal pancreas by treating a human beta cell line derived from fetal pancreas, EndoC-BH3, with high, medium and normal glucose (30, 15 and 5.5mM respectively) for 3 weeks during proliferation and maturation and comparing gene expression using whole transcriptome analysis. The top differentially expressed transcripts (P<10−4) and the most abundant transcripts (Log2 unit>10.5) were validated by real-time RT-PCR. KEGG analyses of the top 500 differentially expressed transcripts identified the metabolic pathway as the top pathway. Among individual genes, high glucose exposure during the maturation upregulated EGR1 (58.6-fold), BIRC5 (37.6-fold), GPBAR1 (15.4-fold), G6PC2 (11.8-fold), CHRNA (4.8-fold), GCK (2.7-fold), INS (2.0-fold), CMIP (1.9-fold) and CHGA (1.4-fold) as compared to normal glucose exposure. EGR1 encodes early-growth response 1, a transcription factor that enhances insulin gene expression, while BIRC5 encodes an apoptotic inhibitor that plays a role in beta cell proliferation. High glucose exposure during the proliferation identified similar differentially expressed genes; however, the changes were more modest as compared with the maturation. Methylation has also been implicated in conveying risk for diabetes due to glucose exposure and several key DNA demethylation enzymes; TET1, 2, 3, were also moderately upregulated. Assessment of the effects of glucose exposure on insulin secretion and total insulin content is ongoing. Our data suggest that short term exposure to high glucose may stimulate expression of a set of genes that promote beta cell proliferation and insulin expression and secretion.

Disclosure

Y.L.Muller: None. K.Wiedrich: None. J.Sutherland: Stock/Shareholder; Pfizer Inc., Bristol Myers. D.Jones: None. L.Baier: None.
177-LB: Association of Pregnancy and Childhood C-Peptide Levels—Hyperglycemia and Adverse Pregnancy Outcome Follow-up Study (HAPO-FUS)
Authors: ZHENG HAO , RAJAMOORTHI ANANTHI , SKOWRONSKI ALICJA , SALEM RANY , LEDUC CHARLES A. , THAKER VIDHU V.
Published: June 2023

Physiological insulin resistance partitions glucose for the growing fetus during the 2nd and 3rd trimester of pregnancy. The HAPO study has demonstrated that pregnancy hyperglycemia is associated with offspring adiposity, hyperglycemia, and glucose intolerance. Maternal insulin is a key regulator of the glucose physiology but does not cross the placenta. The goal of this study was to identify the association of pregnancy and offspring c-peptide levels, measured during oral glucose tolerance test (OGTT).

Method: Using HAPO-FUS data from the NIH-NIDDK repository, multiple linear regression assessed the association of scaled pregnancy fasting and 1-hour c-peptide with cord c-peptide (at birth), and child c-peptide from OGTT at the follow-up visit (ages 10-14 years). Maternal covariates include pregnancy gestational age, BMI, glucose level and field center. Child covariates include age, sex, tanner stage, BMI z-score and glucose level. Multiple imputation was performed using missing at random assumption.

Results: A total of 4,802 mother-child pairs were included. Pregnancy c-peptide was associated with cord c-peptide (fasting 0.02 [0.01-0.03], p <.001, 1-hour 0.01 [0.002-0.02], p =.006). Pregnancy fasting c-peptide was also associated with child OGTT c-peptide (fasting 0.03 [0.02-0.04], p <.001; 1-hour 0.11 [0.08-0.15], p <.001; 2-hour 0.01 [0.007-0.02], p <.001) and pregnancy 1-hour c-peptide (fasting 0.01 [0.007-0.02], p <.001; 1-hour 0.15 [0.12-0.17], p <.001; 2-hour 0.11 [0.09-0.14], p <.001). Similar associations were observed with child insulin levels. Pregnancy c-peptide levels were positively associated with HOMA-IR and negatively with child insulin sensitivity and Matsuda index while adjusting for child BMI z-score and pubertal stage.

Conclusion: Pregnancy insulin levels are strongly associated with the child insulin response during OGTT. This suggests a role in the offspring pancreas developmental programming.

Disclosure

H. Zheng: None. A. Rajamoorthi: None. A. Skowronski: None. R. Salem: Other Relationship; Travere Inc. C. A. Leduc: None. V. V. Thaker: None.

Funding

National Institutes of Health (K23DK110539)
1772-P: Alpha-Cell Heterogeneity Contributes to Phasic Glucagon Release
Authors: MIRANDA CAROLINE A. , DOU HAIQIANG , TOLÖ JOHAN , TARASOV ANDREI I. , RORSMAN PATRIK
Published: June 2023

Glucagon, produced by α-cells of pancreatic islets, is one of the body’s primary tools for elevating blood glucose during hypoglycemia. The exact mechanism linking hypoglycemia to glucagon release by islet α-cells is, however, unclear; we therefore aimed to investigate it using optogenetics. We generated mice harboring the light-activated ion channel channelrhodopsin-2 (ChR2) specifically in α-cells and imaged the effect of optically induced depolarization of plasma membrane (10-ms 470-nm light pulses at 20Hz) at the level of membrane potential, cytosolic Ca2+ ([Ca2+]i) and ATP/ADP ratio. At 1 mmol/L glucose, optostimulation depolarized the electrically active α-cells from -76mV to -8mV, induced a transient surge in [Ca2+]i and elevated glucagon secretion by 200%. In contrast, the glucagonostatic effect of high glucose (>6 mmol/L) was mitigated by optostimulation of α-cells. At 1 mmol/L glucose, the stimulatory effects were abolished by the KATP channel activator diazoxide (100μmol/L) and L-type Ca2+ channel blocker isradipine (10μmol/L). Notably, KATP channel inhibitor tolbutamide (100μmol/L) induced electrical activity in the fraction of α-cells insensitive to low glucose (35%). As stimulation of electrical activity persisted significantly beyond optoactivation, we probed the interplay between electrical activity and energy metabolism. The depolarizing stimulus induced by a cocktail of amino acids ((AA) 2 mmol/L of alanine + arginine +glutamine) or a moderate increase of extracellular K+ (from 4 to 15 mmol/L) reduced ATP/ADP in α-cells exhibiting spontaneous Ca2+ oscillations at low glucose. Surprisingly, in the population of inactive α-cells, the stimulation increased ATP/ADP ratio. These data indicate that α-cells are functionally heterogeneous due to metabolic differences. The observed secretory responses reflect the combination of stimulatory and inhibitory effects in electrically active and silent cells, which may contribute to the phasic nature of AA-induced glucagon secretion.

Disclosure

C.A.Miranda: None. H.Dou: None. J.Tolö: None. A.I.Tarasov: None. P.Rorsman: None.

Funding

Svenska Sällskapet för Medicinsk Forskning (PD20-0056); Swedish Vetenskap Rådet
1781-P: Leptin Regulates Delta-Cell Somatostatin Secretion from Human and Mouse Islets
Authors: HARTIG SEAN M. , COX AARON
Published: June 2023

The delta cell is uniquely positioned in the islet to integrate local signals and circulating nutrient cues to regulate alpha and beta cell function through somatostatin (SST) secretion. In type 2 diabetes (T2D), delta cell responses to ambient glucose are disproportionate and consequently alter insulin and glucagon secretion leading to dysglycemia. However, we know relatively little about the mechanisms influencing delta cells. Thus, understanding factors that regulate delta cell SST secretion may reveal pathogenic mechanisms contributing to T2D and direct new therapies to achieve glucose homeostasis. Leptin is a circulating hormone that potently inhibits insulin and glucagon secretion, but notably, the leptin receptor (LepR) is exclusively expressed on delta cells of human islets. Our preliminary studies demonstrate for the first time that leptin stimulates SST secretion from human islets. Leptin-induced SST corresponded with decreased glucagon and insulin secretion. Leptin effects were conserved in mouse islets and required delta cell specific LepR expression. Our single-cell RNA-seq studies revealed Stat3 target genes become depleted in delta cells that lack LepR, suggesting canonical leptin signals regulate transcriptional activity in delta cells. Along these lines, delta cell specific Stat3 KO islets (Sst-Cre+/wt;Stat3fl/fl) do not respond to leptin. On-going studies in human islets employ pharmacologic and genetic interventions with live functional imaging and unbiased approaches that will reveal the mechanisms of leptin action in human delta cells. These studies are the first to describe leptin effects on delta cells and uncover a unifying mechanism whereby leptin acts indirectly on alpha and beta cells through paracrine SST signaling. As such, our findings are expected to reveal new signaling mechanisms governing islet function that potentially exert therapeutic benefits for T2D.

Disclosure

S.M.Hartig: None. A.Cox: None.
18-LB: Branched-Chain Amino Acids, Acyl-carnitines, and Purine Metabolism Are Associated with Glycemic Variability after Coronary Artery Bypass Graft Surgery
Authors: GUERRERO ARROYO LIZDA I. , ZAHEDI TAJRISHI FARBOD , PEREZ-GUZMAN MIREYA , SAM VARGHESE JITHIN , ABRAHAM AMALIA , SMITH MATTHEW R. , PASQUEL FRANCISCO J.
Published: June 2023

Many patients without diabetes who undergo CABG surgery experience high glycemic variability in the postoperative period. However, the underlying mechanisms associated with glycemic variability after surgery are unknown. We used prospective observational data from 17 patients without diabetes who underwent CABG surgery and wore a Dexcom G6 pro CGM device during the perioperative period. We estimated the coefficient of variation [CV] using CGM values calibrated to point-of-care measurements. We categorized patients into high variability (CV > 10%; n = 5) and low variability (CV ≤ 10%; n = 12) during the first 24 hours after surgery. Metabolic pathways were identified from HILIC positive and Reverse Phase C18 analysis, with metabolites mapped to Kyoto Encyclopedia of Genes and Genomes (KEGG) human pathways using mummichog. Baseline clinical characteristics were similar between the groups. Branched-chain amino acid (BCAA) (e.g. isovalerylglutamic acid), lipids (e.g. acylcarnitine), and purine metabolism (e.g. cGMP) were associated with glycemic variability in the perioperative period, Figure. Metabolomics analysis suggests BCAA, acylcarnitines, and purine pathway metabolites are associated with glycemic variability after CABG surgery.

Disclosure

L. I. Guerrero arroyo: None. F. Zahedi tajrishi: None. M. Perez-guzman: None. J. Varghese: None. A. Abraham: None. M. R. Smith: None. F. J. Pasquel: Consultant; Dexcom, Inc., Medscape, Research Support; Dexcom, Inc., Ideal Medical Technologies.

Funding

National Institutes of Health (K23GM128221); Dexcom, Inc.
181-LB: Congenital Malformations and Medication Use in Women With Type 2 Diabetes—Preliminary Results
Authors: REICHELT ANGELA A.J. , GUERRA GIULIA L. , DE CAMPOS MARIA A. , HIRAKATA VÂNIA N. , OPPERMANN MARIA LUCIA R.
Published: June 2023

Background: Congenital malformations occur more frequently in pregnancies of women with type 2 diabetes, mainly attributed to poor glycemic control. However, using certain medications may also contribute. Aim: To describe medication use by conception time in women with type 2 diabetes.

Methods: In this retrospective cohort, women with singleton pregnancies from two tertiary care hospitals were enrolled. Data on maternal age, time of diabetes diagnosis, medication use, BMI, HbA1c, and congenital malformations were collected from medical records between May 2005 and June 2021. We excluded four neonates with genetic/chromosomic diseases. Poisson regression with robust estimates was used to evaluate risk factors for congenital malformations.

Results: We included 634 women; 212 (33.5%) presented overt diabetes; 136 (21.5%) arrived at prenatal care in the first trimester; 18 (2.8%) had a miscarriage; 560 (88.3%) delivered alive newborns, and 17 (2.7%), stillbirth. Only 227 women (35.8%) had an HbA1c measured in the first trimester, and 304 (48.6%) had an HbA1c before 28 weeks of gestation. Congenital malformations were diagnosed in 77 (13.7%) neonates; of these, 56 (73%) were cardiac defects, isolated or combined with other malformations. Few women used folate in the first trimester (115; 18.1%), almost always introduced after pregnancy diagnosis; 353 (55%) used oral antidiabetics; 116 (18.3%), any anti-hypertensive medication, and 16 (2.5%), statins. In adjusted models including age, BMI and HbA1c, sulfonylurea was associated with increased risk of congenital malformation: RR 2.7, 95% CI 1.3-5.6, p=0.009, when HbA1c in the first trimester entered the model (n=200); and RR 1.64, 95% CI 1.0-2.6, p=0.038, with an HbA1c measured before 28 weeks (n=539).

Conclusion: In this cohort of women with type 2 diabetes, congenital malformations were more frequent than in the general population. Sulfonylurea was the only medication associated with an increased risk of congenital malformation.

Disclosure

A. A. J. Reichelt: None. G. L. Guerra: None. M. A. De campos: None. V. N. Hirakata: None. M. R. Oppermann: None.

Funding

FIPE-HCPA (2016-0331)
195-OR: To Which Degree Do Alpha Cells Shape the Role of the Beta Cells First Responders?
Authors: KRAVETS VIRA , LEVITT CLAIRE H. , BENNINGER RICHARD K.
Published: June 2023

Calcium (Ca2+) uptake drives glucose-stimulated insulin secretion from the pancreatic β-cells. The “1st responder” subpopulation of β-cells disproportionally control the Ca2+ uptake during the first phase, which is disrupted with ageing and in diabetes. Here we determine whether alpha and delta cells play a formative role in the 1st responder β-cells state. We used MIP-CreER GCaMP6s mouse model which expresses Ca2+-sensitive GFP specifically in β-cells. We performed simultaneous recording of Ca2+ dynamics and gap junction permeability in individual islets. We stimulated islets with glucose, and with the GLP1-R antagonist, exendin 9-39 (Ex9). Based on the first-phase Ca2+ dynamics we defined the “1st responder” and the “last responder” cells. We tested their consistency under repeated glucose stimulation with and without the Ex9. We next stained them for insulin, glucagon, and somatostatin and measured distances in 3D from all β-cells to alpha and delta cells. The Ex9 disrupted the 1st responder consistency (only half of the original 1st responders remained such under repeated glucose stimulation), compared to the control experiment. Ex9 increased the islet's first-to-last cell response time by 150 +/- 74 seconds making islet's response to glucose two times more heterogeneous compared to control (p=0.0517). On average 1st responders were located closer to the alpha cells, and last responders - further from them (p=0.0039). At the same time, first responders had significantly less delta cell neighbors compared to the last responders (p=0.0137). Our gap junction permeability data showed no gap junction activity in alpha-beta cell couples. In conclusion, 1st responder beta cells have more alpha cell and less delta cell neighbors than last responders. The role of the alpha cell in the formation of the 1st responder cell state is likely realized via paracrine interaction.

Disclosure

V.Kravets: None. C.H.Levitt: None. R.K.Benninger: None.

Funding

Burroughs Wellcome Fund (25B1756 to V.K.); National Institutes of Health (R01DK102950, R01DK106412 to R.K.B.); Human Islet Research Network (UC24DK104162 to V.K.)
2-OR: Risk Factors for Continuous Glucose Monitoring (CGM)-Detected Hypoglycemia in Very Old Adults with Type 2 Diabetes
Authors: FANG MICHAEL , JEON YEIN , CORESH JOSEF , ECHOUFFO TCHEUGUI JUSTIN , ZEGER SCOTT L. , SELVIN ELIZABETH
Published: June 2023

Introduction: Risk factors for hypoglycemia in very old adults with type 2 diabetes are uncharacterized. CGM identifies biochemical hypoglycemia but is not widely used in type 2 diabetes.

Methods: We conducted a cross-sectional analysis of 282 adults with type 2 diabetes (mean age 84 years; 32% using insulin or sulfonylureas [SUs]) in the Atherosclerosis Risk in Communities study (2021-2022). Participants wore the Abbott Libre Pro monitor (blinded) for up to 14 days. We examined the percentage of time participants had glucose readings <70 mg/dl (T<70), stratified by medication use. We considered T<70 separately during daytime (6:00AM-11:59 PM) and overnight (12:00AM-5:59 AM).

Results: There was substantial hypoglycemia in very old adults using insulin or SUs, especially overnight (median T<70: 5.1%) (Figure). In this population, females and those with cardiovascular disease, poor physical functioning, or a prior history of severe hypoglycemia experienced the most overnight hypoglycemia. T<70 was low in those not using insulin or SUs, but those with dementia were at an increased risk for overnight hypoglycemia.

Conclusion: Cardiovascular disease, functional impairment, and prior severe hypoglycemia were major risk factors for nocturnal hypoglycemia in very old adults using insulin or SUs. The benefits of CGM should be explored for these patients.

Disclosure

M.Fang: None. Y.Jeon: None. J.Coresh: Consultant; Healthy.io Ltd, SomaLogic. J.Echouffo tcheugui: None. S.L.Zeger: None. E.Selvin: None.
222-OR: Metformin Reduces Fasting Glycemia in Well-Controlled Type 2 Diabetes by Promoting Aerobic Glycolysis Independent of Decreasing Endogenous Glucose Production
Authors: SARABHAI THERESIA , LAMOIA TRACI E. , FRIESL SOPHIE , JONUSCHEIT MARC , PETERSEN KITT , SHULMAN GERALD I. , RODEN MICHAEL
Published: June 2023

It is well established that metformin improves glycemic control in individuals with poorly-controlled type 2 diabetes (T2D) by reducing rates of endogenous glucose production (EGP) mediated by inhibition of hepatic gluconeogenesis. However, the mechanism by which metformin reduces blood glucose levels in well-controlled individuals with T2D is still unknown. To address this question, we examined rates of EGP, lactate turnover and hepatic triglyceride (TAG), ATP and glycogen content in near-normoglycemic individuals with T2D (n=10, HbA1c 7±1%) with (M+; 1000 mg bid x 2 wks) and without (M-; 2 wks) metformin treatment using the PINTA method with [2H7]glucose and [3-13C]lactate tracer infusions in combination with 1H- /31P- /13C- magnetic resonance spectroscopy. Metformin treatment did not affect rates of EGP, but reduced fasting plasma glucose concentrations by 30% (p<0.01 vs. M-), which could be attributed to increased rates of glucose clearance (+18%, p<0.005 vs. M-) resulting in increased lactate production (+14%, p<0.01 vs. M-). These changes were associated with decreased hepatic ATP content (-20%, p<0.05 vs. M-), increased hepatic glycogen content (+40%, p<0.05 vs. M-) and no changes in hepatic TAG content. Conclusion: In contrast to the glucose-lowering effect of metformin in poorly-controlled T2D, which is due to reductions in gluconeogenesis, this study demonstrates that in well-controlled T2D metformin reduces fasting glycemia - independent of reductions in EGP - primarily by increasing rates of aerobic glycolysis as reflected by increased peripheral glucose clearance and lactate production as well as reduced hepatic ATP content, which is consistent with metformin-induced inhibition of mitochondrial electron transport chain activity.

Disclosure

T.Sarabhai: None. T.E.Lamoia: None. S.Friesl: None. M.Jonuscheit: None. K.Petersen: Advisory Panel; Novo Nordisk, Research Support; Merck Sharp & Dohme Corp., Gilead Sciences, Inc. G.I.Shulman: Consultant; Novo Nordisk, DiCerna Pharmaceuticals, Inc., Bayer Consumer Care AG, Kriya Therapeutics, Arrowhead Pharmaceuticals, Inc., ESPERION Therapeutics, Inc., Other Relationship; AstraZeneca, Merck & Co., Inc., Janssen Research & Development, LLC, iMetabolic Biopharma Corporation, Maze Therapeutics, 89bio, Inc., Equator Therapeutics, Inc., Generian Pharmaceuticals, Fortress Biotech, Inc., OrsoBio, Aro Biotherapeutics Company, Stock/Shareholder; Levels Health, Inc. M.Roden: Advisory Panel; Eli Lilly and Company, Consultant; TARGET PharmaSolutions, Inc., Research Support; Boehringer-Ingelheim, Novo Nordisk, Novartis, Sanofi.
261-OR: Autonomous Artificial Intelligence (AI) Testing for Diabetic Eye Disease (DED) Closes Care Gap and Improves Health Equity on a Systems Level
Authors: ALVIN LIU T.Y. , HUANG JANE , LEHMANN HAROLD , WOLF RISA M. , CHANNA ROOMASA , ABRÀMOFF MICHAEL D.
Published: June 2023

We aimed to examine the change in adherence to annual diabetic eye disease (DED) testing in an integrated healthcare system (Johns Hopkins Community Physicians 30+ community based primary care clinics) before and after deployment of autonomous artificial intelligence (AI). Adherence to annual DED testing is defined as completed evaluation by either a human ophthalmology provider, or autonomous AI within a given calendar year. During the COVID pandemic, autonomous AI (IDx-DR, Digital Diagnostics, Coralville, IA) was deployed at multiple clinics, so that by 2021, some clinics had autonomous AI (AI sites), while others did not (non-AI sites). Overall adherence in 2019 (pre-AI) and 2021 (with AI) were compared, and stratified by demographics, using chi-square or Fisher’s exact test. Changes from 2019 to 2021 in odds of adherence within each subgroup were assessed for significant differences by site type (AI vs. non-AI), using logistic regression with a site type-by-time interaction term. From 2019 to 2021, the overall adherence rate increased from 42.6% to 55.5% at AI sites (1949 patients), and increased from 38.0% to 41.0% at non-AI sites (5379 patients). The increase in overall adherence rate at AI sites was significantly greater than that at non-AI sites (p<0.001). Various patient subgroups (M, F, ≥65 yo, <65 yo, Black, White, Medicare/military/commercial insurance) at AI sites demonstrated a significantly greater (p<0.05) compliance rate increase when compared to the same subgroups at non-AI sites. For Black patients, there was no difference in adherence rate between AI sites and non-AI sites (38.5% vs. 37.1%, p=0.45) in 2019, but the difference became significant (p<0.001) in 2021 due to increased adherence at the AI sites (58.0%) vs. 38.8% at non-AI sites. Autonomous AI improved DED testing adherence in a large, diverse patient cohort and decreased disparity in Black patients, a historically-disadvantaged subgroup.

Disclosure

T.Liu: None. J.Huang: None. H.Lehmann: None. R.M.Wolf: Research Support; Dexcom, Inc., Boehringer Ingelheim Inc. R.Channa: None. M.D.Abràmoff: Board Member; Digital Diagnostics, Consultant; AbbVie Inc., NovaGo Therapeutics AG, Other Relationship; Digital Diagnostics, Stock/Shareholder; Digital Diagnostics.

Funding

Digital Diagnostics
275-OR: Association between Treatment Adherence and CGM Outcomes in People with T1D Using Smart Insulin Pens in a Real-World Setting
Authors: DANNE THOMAS , HARTVIG NIELS V. , KAAS ANNE , KNUDSEN NIKOLINE N. , MADER JULIA K.
Published: June 2023

Adherence to insulin therapy can be challenging for individuals with T1D. This analysis explored how adherence to basal and bolus insulin injections influences glycemic outcomes. Data were collected from adults (≥18 years) administering basal insulin (degludec) and bolus insulin (aspart or faster aspart) using smart insulin pens with CGM; data were aggregated in 14-day periods. Treatment adherence was defined as the number of missed basal insulin doses (>40 hrs between doses), flex basal insulin doses (dosing time deviated >±6 hrs from previous day) and missed bolus insulin doses (meals with no bolus dose within -15 to +60 mins from meal onset). Glycemic outcomes included time in range (TIR), time below range, glucose management index (GMI), and coefficient of variation. Multinational data from 403 adults who had 3588 14-day periods with ≥70% CGM coverage were analyzed. Individuals with one missed basal dose per 14-days had a lower TIR (-4.04% [95% CI: -6.83; -1.26]) and higher GMI (0.20% [95% CI: 0.02; 0.38]) than individuals without missed basal doses; flex basal doses were not associated with TIR changes. Missed bolus insulin doses were also associated with lower TIR (Table). These real-world data confirm associations between missed basal and bolus insulin doses and impaired TIR, highlighting a need for digital tools such as smart insulin pens to help individuals manage their diabetes.

Disclosure

T.Danne: Research Support; Abbott Diabetes, AstraZeneca, Bayer Inc., Boehringer-Ingelheim, Dexcom, Inc., Eli Lilly and Company, Novo Nordisk A/S, Sanofi, Medtronic, Stock/Shareholder; DreaMed Diabetes, Ltd. N.V.Hartvig: Employee; Novo Nordisk A/S, Stock/Shareholder; Novo Nordisk A/S. A.Kaas: Employee; Novo Nordisk A/S, Stock/Shareholder; Novo Nordisk A/S. N.N.Knudsen: Employee; Novo Nordisk. J.K.Mader: Advisory Panel; Novo Nordisk A/S, Abbott Diabetes, Roche Diabetes Care, Eli Lilly and Company, Sanofi, Medtronic, Becton, Dickinson and Company, Pharmasense, embecta, Research Support; A. Menarini Diagnostics, Abbott Diabetes, Roche Diabetes Care, Dexcom, Inc., Profusa, Inc., Speaker's Bureau; Novo Nordisk A/S, A. Menarini Diagnostics, Abbott Diabetes, Roche Diabetes Care, Eli Lilly and Company, Sanofi, Boehringer Ingelheim Inc., Becton, Dickinson and Company, Ypsomed AG, Viatris Inc., Servier Laboratories, Medtrust, Stock/Shareholder; Decide Clinical Software GmbH.

Funding

Novo Nordisk A/S
280-LB: Efficacy of a Respiratory Syncytial Virus (RSV) Prefusion F Protein Vaccine (RSVPreF3 OA) in Older Adults with Preexisting Medical Conditions
Authors: FELDMAN ROBERT G. , ANTONELLI INCALZI RAFFAELE , STEENACKERS KATIE , LEE DONG-GUN , FISSETTE LAURENCE , DAVID MARIE-PIERRE , MARÉCHAL CÉLINE , KOSTANYAN LUSINE , VAN DER WIELEN MARIE , HULSTROEM VERONICA
Published: June 2023

Background: Adults with diabetes and other conditions are at increased risk of severe RSV disease and hospitalization. In a phase 3 placebo-controlled study (NCT04886596) in adults ≥60 years, RSVPreF3 OA showed 82.6% vaccine efficacy (VE) against RSV-related lower respiratory tract disease (RSV-LRTD) and 71.7% against RSV-related acute respiratory infection (RSV-ARI). We assessed VE among participants with different BMI and with selected pre-existing metabolic or endocrine conditions (eg, diabetes) that increase the risk of severe RSV disease.

Methods: Adults ≥60 years were 1:1 randomized to receive 1 dose of RSVPreF3 OA or placebo before the RSV season. VE against first occurrence of RSV-LRTD and RSV-ARI was calculated for different subgroups (Table).

Results: In total, 24,966 participants received RSVPreF3 OA (12,467) or placebo (12,499). Of these, 25.7% (RSVPreF3 OA) and 25.9% (placebo) had ≥1 metabolic or endocrine condition (22.9% diabetes). Mean BMI in both groups was 29.1 kg/m2. In participants with overweight/obesity, VE was 85.6% (RSV-LRTD) and 76.3% (RSV-ARI). In those with ≥1 metabolic or endocrine condition, VE was 100% (RSV-LRTD) and 79.4% (RSV-ARI) (Table).

Conclusion: RSVPreF3 OA is highly efficacious against RSV-LRTD and RSV-ARI in adults ≥60 years with overweight/obesity and in those with ≥1 metabolic or endocrine condition.

Disclosure

R. G. Feldman: Research Support; GSK, Speaker's Bureau; Amgen Inc., GSK. V. Hulstroem: Employee; GlaxoSmithKline plc., Stock/Shareholder; GlaxoSmithKline plc. R. Antonelli incalzi: None. K. Steenackers: Employee; Johnson & Johnson Medical Devices Companies. D. Lee: None. L. Fissette: Employee; GlaxoSmithKline plc., Stock/Shareholder; GlaxoSmithKline plc. M. David: Employee; GlaxoSmithKline plc., Stock/Shareholder; GlaxoSmithKline plc. C. Maréchal: Employee; GlaxoSmithKline plc., Stock/Shareholder; GlaxoSmithKline plc. L. Kostanyan: None. M. Van der wielen: Employee; GlaxoSmithKline plc.

Funding

GlaxoSmithKline Biologicals SA
289-OR: Defining Pathway-Selective Insulin Resistance in Type 2 Diabetes Using iPS Cell-Derived Hepatocytes
Authors: GATTU ARIJEET , KROOK ANNA , ZIERATH JULEEN R. , MANN MATTHIAS , RONALD KAHN C.
Published: June 2023

Hepatic insulin resistance is central to type 2 diabetes (T2D), fatty liver disease, and metabolic syndrome. To identify the fundamental, cell-autonomous defects underlying hepatic insulin resistance in T2D, we have used inducible human pluripotent stem (iPS) cells derived from 16 individuals with and without T2D differentiated to hepatocytes (iHeps) and studied in vitro. Consistent with pathway selective insulin resistance, we find that insulin failed to suppress gene expression of critical gluconeogenic enzymes (PCK1, G6PC) but continued to stimulate increased expression of the lipogenic enzymes, fatty acid synthase and acetyl Co-A carboxylase 1 in T2D iHeps. iHeps from T2D also displayed reduced insulin receptor tyrosine phosphorylation and reduced phosphorylation through the IRS/Akt pathway. Global phosphoproteomics in control and T2D iHeps identified 378 unique phosphosites regulated by insulin, and many dysregulated phosphosites within the classical insulin signaling pathway (IRS, AKT1/2, GSK3, FOXO1, RPS6KB1, TSC2) and components of gene transcription regulation, membrane trafficking, Rho-GTPases, vesicle transport. Using a kinome-wide data set created with synthetic peptide libraries to profile almost all functional known human serine/threonine kinases, we found the alterations in insulin signaling mapped to AKT, P70S6K, P90S6K, RSK, PKCτ, and SGK kinases. Thus, iHeps from T2D patients show pathway-selective insulin resistance with a loss of suppression of gluconeogenesis by insulin yet persistent activation of lipogenesis, even in vitro, in the absence of any circulating factor exposure. T2D iHeps also show a dysregulated phosphorylation network that provides new clues to the kinases whose action is altered in T2D and hepatic insulin resistance.

Disclosure

A.Gattu: None. A.Krook: None. J.R.Zierath: None. M.Mann: None. C.Kahn: None.

Funding

National Institutes of Health (T32DK007260-46)
29-OR: Diabetic Wound Keratinocytes Induce Macrophage JMJD3–Mediated Nlrp3 Expression
Authors: WOLF-FORTUNE SONYA , MOON JADIE , JOSHI AMRITA , MAZUMDER PURBA , BARRETT EMILY , MANGUM KEVIN D. , GALLAGHER KATHERINE
Published: June 2023

Macrophage (Mφ) plasticity is critical for normal wound repair; however, type 2 diabetic (T2D) wound Mφs display a delayed chronic inflammatory state that prevents the resolution of wound inflammation. Increased NLRP3 inflammasome gene expression and activation in Mφs contributes to impaired wound healing in T2D and is induced by diabetic wound environment factors, yet the molecular mechanisms regulating this are unclear. Our lab has shown that keratinocytes, structural cells in the skin, regulate skin inflammation and Mφ phenotype during wound healing by preferentially producing proinflammatory cytokines. Thus, this project explores the molecular mechanisms by which keratinocytes drive increased Nlrp3 expression in diabetic wound Mφs. Here, we found that Nlrp3 expression is increased in diabetic wound Mφs late post-injury, and this can be induced by stimulation of normal wound Mφs with diabetic wound keratinocyte supernatant. Further, we found that stimulation of Mφs with diabetic wound keratinocyte supernatant resulted in decreased H3K27me3 deposition at the Nlrp3 promoter. Using genetically engineered mice (Jmjd3 fl/fl lyz2cre), we demonstrate that JMJD3, a demethylase specific for H3K27, controls Mφ-mediated Nlrp3 expression and inflammasome activation during wound healing. Importantly, we show that diabetic wound keratinocytes induce Jmjd3 expression in Mφs via IL1 receptor and MyD88 upstream signaling. Interestingly, we found that IL1α is increased in human and murine wound diabetic keratinocytes compared to nondiabetic controls and stimulation of Mφs with IL1α increases Nlrp3 expression via a H3K27me3/JMJD3-mediated mechanism. Thus, our data suggest a role for keratinocyte IL1α in driving increased Nlrp3 expression in chronic diabetic wound Mφs via JMJD3. Continued investigation into the dysregulation of the keratinocyte-Mφ axis in diabetic wounds is key to developing novel treatments for non-healing wounds in T2D patients.

Disclosure

S. Wolf-Fortune: None. J. Moon: None. A. Joshi: None. P. Mazumder: None. E. Barrett: None. K.D. Mangum: None. K. Gallagher: None.

Funding

National Institutes of Health (1K99DK133828-01, P30DK089503, R01HL137919, R01DK124290, R01HL15627401, R01DK127531)
294-OR: Hepatic Integrin ß1 Subunit Is Required for Liver Insulin Resistance but Not Fatty Liver in Diet-Induced Obese Mice
Authors: TREFTS ELIJAH , GHOSHAL KAKALI , DO ALLISON V. , GUERIN AMANDA , GUAN CHRISTOPHER , BRACY DEANNA , LANTIER LOUISE , ZENT ROY , POZZI AMBRA , WASSERMAN DAVID H.
Published: June 2023

Obesity can lead to liver fibrosis and a selective insulin resistance whereby insulin-stimulated lipogenesis is maintained and liver triglycerides (TG) are elevated, while insulin suppression of liver glucose production (Ra) is impaired. The hypothesis that extracellular matrix (ECM) proteins of the fibrotic liver signal via integrin receptors contributing to hepatic insulin resistance was tested. Integrins consist of an α subunit that confers ligand specificity and a β subunit that interacts with adhesion proteins that transmit signals that lead to adaptations in cell function. The integrin β1 subunit is the primary isoform in the liver. Lean and diet-induced obese (DIO) C57Bl/6J mice with hepatocyte-specific deletion of the integrin β1 subunit (hitgβ1) knockout (KO) and wild type littermates (WT) were studied. Insulin clamps were performed in hitgβ1 KO and WT mice. Ra and glucose utilization (Rd) were measured before and during clamps. Metabolism in lean mice was unaffected by hitgβ1 KO. DIO WT mice were resistant to insulin suppression of Ra and had elevated liver TG. This insulin resistance to suppression of Ra was completely alleviated in DIO hitgβ1 KO mice. However, liver TG remained elevated. Alleviation of hepatic insulin resistance in DIO hitgβ1 KO mice was reflected by a greater activation of the insulin signaling pathway in hepatocytes. In contrast, impaired response of enzymes that participate in cytoskeletal organization and mitochondrial oxidation were observed in DIO hitgβ1 KO mice. It is postulated that impaired cytoskeletal organization decreases mitochondrial oxidation through effects on mitochondrial interactions. Impaired oxidation may contribute to the elevated TG that is present despite the improvement in insulin action. In conclusion, the hitgβ1 subunit contributes to selective hepatic insulin resistance in DIO mice. These data provide a mechanistic basis for an ECM - integrin receptor - insulin resistance axis in DIO mice.

Disclosure

E.Trefts: None. D.H.Wasserman: None. K.Ghoshal: None. A.V.Do: None. A.Guerin: None. C.Guan: None. D.Bracy: None. L.Lantier: None. R.Zent: None. A.Pozzi: None.

Funding

National Institutes of Health (DK050277, DK054902, DK059637)
295-OR: Mechanisms of Antigen-Specific Immunotherapy following Tolerance Induction to a CD4 Hybrid Insulin Peptide Epitope and the Impact on CD8 T Cell Dysfunction
Authors: DILISIO JAMES E. , BAKER ROCKY L. , HASKINS KATHRYN M.
Published: June 2023

Type 1 diabetes is the culmination of T cell mediated autoimmunity resulting in the destruction of insulin-producing beta cells. Islet-derived hybrid insulin peptides (HIPs), recognized by autoreactive CD4 T cells, are likely dominant T cell epitopes in the NOD mouse model of autoimmune diabetes. The 2.5HIP is formed by the fusion of a fragment of insulin C-peptide with a natural cleavage product of chromogranin A, generating a neoepitope. When the 2.5HIP was delivered as an immunotherapy on tolerance inducing PLG-nanoparticles, islet grafts functioned longer in transplanted, diabetic NOD mice. Tolerance induction to this single neoepitope induced dysfunctional cytokine production in autoreactive CD4 and CD8 T cells specific for other known islet antigens. Here we used both prediabetic NOD mice and diabetic transplant recipients to examine mechanisms of peripheral tolerance induction to a HIP. Using the Tiger IL10-GFP reporter mouse, we observed a substantial increase in the proportion of (CD25+) Treg and (CD25-) Tr1 2.5HIP tetramer+ CD4 T cells that expressed IL10 in the islets, spleen, and draining lymph node of 2.5HIP nanoparticle treated mice. Autoreactive, IGRP tetramer+ CD8 T cells displayed a trafficking defect and accumulated in secondary lymphoid tissue with a concomitant reduction within islets. The proportion of cytolytic, CX3CR1+ IGRP tetramer+ CD8 T cells that infiltrated islets was also reduced. IL10 generated by both Treg and Tr1 2.5HIP tet+ T cells may directly suppress IGRP tetramer+ CD8 T cells or suppress an intermediate cell type such as a dendritic cell, causing CD8 T cell dysfunction. Examining how antigen-specific immunotherapies suppress multiple autoreactive T cells specificities may help inform future therapies without the need for immunosuppression.

Disclosure

J.E.Dilisio: None. R.L.Baker: None. K.M.Haskins: None.

Funding

National Institutes of Health (5T32DK120520-03, 2R01DK081166-11); JDRF (2-SRA-2020-907-S-B)