bluuebunny/crossref_metadata_2025 huggingface dataset:
2000-LB: Multiome Profiling of Human Islets Nominates Beta-Cell–Specific Cytokine Response Profiles Underlying Type 1 Diabetes
Authors: ROBERTSON CASSIE , WANG XIAOOU , ORCHARD PETER , MENG JERRY , DOLGACHEV VLADISLAV , MANICKAM NANDINI , NARISU NARISU , ERDOS MICHAEL , COLLINS FRANCIS S. , CHEN SHUIBING , PARKER STEPHEN C.
Published: June 2024

Inflammation in the islet may be an early trigger of beta cell stress which can lead to islet autoimmunity and type 1 diabetes (T1D). We exposed human islets (N=8 donors) to proinflammatory cytokines (IL-1-beta and TNF-alpha) and used single nucleus multiomic sequencing to jointly profile RNA expression and chromatin accessibility (10X Genomics Multiome). We pooled cytokine-treated and untreated islets for single nucleus experiments using a randomized block design, which reduced sample-to-sample variability and eliminated batch confounding of treatment effects. We included 37,170 high quality nuclei in downstream analysis and identified transcriptional response to cytokines in three major islet cell types (887 genes in alpha cells, 2,998 genes in beta cells, 547 genes in ductal cells), including upregulation of MHC class I in all three cell types. Beta cells showed significant downregulation in marker gene expression (INS fold change = 0.55, p = 3 x 10-5), but marker gene expression did not change in alpha (GCG fold change in alpha cells = 0.68, p = 0.07) or ductal cells (KRT19 fold change in ductal cells = 0.82, p = 0.60). Pathway analyses indicated upregulation of proinflammatory pathways in all three cell types and downregulation of a hallmark beta cell pathway in beta cells only (p = 0.005). Finally, pathway analysis of cell type-specific gene expression changes, using residualized treatment effect sizes per cell type, indicated enhanced upregulation of the TGF-beta signaling pathway in beta cells as compared to alpha or ductal cells. In conclusion, using single nucleus profiling with a randomized study design, we found beta cell-specific responses to proinflammatory cytokines which may contribute to beta cell demise underlying type 1 diabetes. Analyses of cytokine effects on chromatin accessibility to nominate upstream transcriptional regulators are underway.

Disclosure

C. Robertson: None. X. Wang: None. P. Orchard: None. J. Meng: None. V. Dolgachev: None. N. Manickam: Employee; 10x Genomics. N. Narisu: None. M. Erdos: None. F.S. Collins: None. S. Chen: None. S.C. Parker: Research Support; Pfizer Inc.

Funding

NIH NIDDK (DK127777); NIH NIDDK (DK007245)
2031-LB: Serotonin Is a Novel Player in Selective Hepatic Insulin Resistance
Authors: EUN NAM JUNG , HWANG INSEON , CHOI WON-IL , LEE MINJU , CHOI WONGUN , CHOI WONSUK , MOON YOUNG-AH , KIM HAIL
Published: June 2024

Insulin is known to induce lipogenesis and inhibit gluconeogenesis in the liver. Therefore, hepatic lipogenesis is supposed to be downregulated in insulin resistance, but, in reality, hepatic lipogenesis is paradoxically upregulated. Recently, Serotonin (5-HT) has been implicated in both hepatic lipogenesis and gluconeogenesis. However, the molecular mechanism and the potential crosstalk between 5-HT and insulin signaling pathways have not been explored yet. Here, we investigated the multifaceted roles of 5-HT in the liver which may provide new insights into the complex regulatory networks governing hepatic glucose and lipid homeostasis.

AML-12 cells were incubated with 5-HT in the presence or absence of various inhibitors. Signaling pathways were explored in liver specific Htr2a (HTR2ALKO), Htr2b (HTR2BLKO), Insr (LIRKO) and both Htr2a and Insr (HTR2A/IRLKO) knockout mice after injection of 5-HT or insulin via portal vein.

In AML-12 cells, 5-HT activates AKT phosphorylation through PI3K and intracellular calcium flux resulting in the activation of SREBP-1c. Direct injection of 5-HT through portal vein induced activation of AKT and SREBP-1c, which were diminished specifically in HTR2ALKO mice. When the hepatic insulin signaling was inhibited by LIRKO or S961, 5-HT induced AKT phosphorylation but insulin could not. According to HFD fed condition, weight and size of liver and hepatic steatosis are decreased in HTR2A/IRLKO mice, comparing LIRKO mice. In terms of gluconeogenesis, 5-HT phosphorylates CREB via HTR2B which was mediated by PKG, not by PKA and 5-HT injection could not induce CREB activation in HTR2BLKO mice.

These results suggest that during insulin resistance 5-HT can increase both lipogenesis and gluconeogenesis in the liver via HTR2A-PI3K-AKT-SREBP1c signaling and HTR2B-PKG-CREB signaling, respectively. Therefore, the selective hepatic insulin resistance could be attributed to the 5-HT induced activation of lipogenesis and gluconeogenesis, independently from insulin and glucagon.

Disclosure

J. Nam: None. I. Hwang: None. W. Choi: None. W. Choi: None. W. Choi: None. Y. Moon: None. H. Kim: None.

Funding

NRF-2021R1A2C3005108; NRF-2020M3A9E4038695
2036-LB: Identification of a Hepatocyte Subpopulation That Simultaneously Expresses Gluconeogenic and Lipogenic Genes in the Fed State
Authors: OKADA JUNICHI , LANDGRAF AUSTIN , XIAOLI ALUS , QIU YUNPING , LIU LI , SCHUSTER VICTOR L. , KURLAND IRWIN J. , YANG FAJUN , ELISCOVICH CAROLINA , SHINODA KOSAKU , PESSIN JEFFREY
Published: June 2024

Introduction & Objective: Pathway-selective insulin resistance in the liver is a concept where gluconeogenesis is selectively insulin resistant compared to de novo lipogenesis. Thus, treatment with large doses of insulin to control gluconeogenesis might lead to excessive triglyceride synthesis. To understand the discrepancy in the pathogenesis between the two pathways, we examined the zonation of hepatocyte specificity of gluconeogenic and lipogenic gene expression under normal physiological conditions in mice.

Methods: Using a combination of single cell RNA sequencing (scRNA-seq) and single molecule Fluorescence In Situ Hybridization (smFISH), we examined the normal regulation of gluconeogenic genes (such as Pck1) and lipogenic genes (such as Fasn) under various feeding/fasting conditions. Mass spectrometry with stable isotope using isolated pericentral and periportal hepatocytes confirmed gene expression results. PrimeFlow RNA Assay was performed to further understand the relationship between these genes.

Results: scRNA-seq showed a subset of periportal hepatocytes in the fed state that expressed both Pck1 and Fasn. smFISH not only confirmed the scRNA-seq data but also showed a subset of periportal hepatocytes that co-transcribed Pck1 and Fasn in the fed state. Mass spectrometry with stable isotope confirmed basal gluconeogenesis in the periportal hepatocytes in the fed state, suggesting that the subset of hepatocytes was undergoing gluconeogenesis in the fed state. PrimeFlow RNA assay followed by FACS enabled us to isolate these hepatocytes for further analysis.

Conclusion: We have discovered a new subset of hepatocytes that express both lipogenic and glucogenic genes under normal physiological conditions. These hepatocytes are by default pathway-selectively insulin resistance. Analyzing and characterizing as well as possibly targeting these hepatocytes might help us understand the pathogenesis of insulin resistance.

Disclosure

J. Okada: None. A. Landgraf: None. A. Xiaoli: None. Y. Qiu: None. L. Liu: None. I.J. Kurland: None. F. Yang: None. C. Eliscovich: None. K. Shinoda: None. J. Pessin: None.
2046-LB: Selective, Acute Stimulation of Sympathetic Activity in Brown Adipose Tissue Improves Glycemic and Lipid Profiles in Mice
Authors: NERI DANIELE , FOHN ALEXIS , BOZEC DOMINIQUE , HEINE MARKUS , WORTHMANN ANNA , CHEN XINHONG , HEEREN JOERG , ZELTSER LORI M.
Published: June 2024

Brown adipose tissue (BAT) activity is linked to improved cardiometabolic health, and acute stimulation of BAT has been shown to reduce glycemia and triglyceridemia, which is protective against metabolic diseases such as type 2 diabetes. However, most BAT-stimulating protocols involve deliberate cold exposure or sympathomimetic drugs. Although effective, these methods can increase cardiovascular risk by increasing general sympathetic tone. Our lab has developed a model to selectively activate the sympathetic nerves controlling BAT activity in mice, and we are now dissecting the contribution of BAT activity to systemic metabolism without affecting other peripheral organs. We have used a combination of genetically engineered mouse lines, neurotrophic viruses, chemogenetics, metabolic recordings, and next generation sequencing to carefully study how the sympathetic nervous system controls different aspects of BAT activity. Our results show that the selective acute activation of BAT-projecting sympathetic nerves improves glucose tolerance in mice. This acute stimulation also increases total energy expenditure and lowers the respiratory exchange ratio, which is consistent with increased BAT activity. Finally, we show that the transcriptomic profile of BAT in these mice is in line with expected changes associated with increased BAT activity. BAT represents one of the most promising targets for new therapeutics to restore euglycemia. Our novel approach to selective sympathetic regulation pinpoints the undisputed role of BAT to whole-body glucose and energy management in mice. This targeted activation holds promises for novel therapies against type 2 diabetes while circumventing potential cardiovascular risks associated with traditional BAT stimulation methods.

Disclosure

D. Neri: None. A. Fohn: None. M. Heine: None. A. Worthmann: None. X. Chen: None. J. Heeren: None. L.M. Zeltser: None.

Funding

R01DK125094; P01AG032959
215-OR: Polygenic Scores for Metabolic Diseases Are Associated with Gene Expression Networks across Tissues
Authors: BRYAN CHRISTOPHER , SMITH KIRK , MANNING ALISA , MERCADER JOSEP M. , UDLER MIRIAM
Published: June 2024

In type 2 diabetes (T2D), coronary artery disease (CAD) and obesity, disease risk across thousands of genetic variants can be captured with global extended polygenic scores (gePS), yet knowledge of underlying disease pathways remains limited. Expression Quantitative Trait Scores (eQTS) connecting gePS to gene expression could help prioritize disease-causing genes and pathways in specific tissues.

We generated gePS for T2D, CAD, and body mass index (BMI) in the Genotype-Tissue Expression (GTEx) database of 838 individuals and 49 tissues. Associations between gePS and phenotypes were confirmed in a hospital-based biobank. eQTS were calculated using a linear model of association between gePS and tissue transcript expression level, adjusting for age, sex, and 5 PCs. Gene set enrichment was performed using Enrichr with Gene Ontology pathway sets and Fisher’s Exact Test (Q < 0.05). Each gePS was strongly associated with >3,000 strong transcript expression levels (eQTS) across multiple tissues at Q<0.05. T2D and BMI eQTS in multiple tissues were each significantly enriched for pathways related to mitochondrial function (Q<0.01), with the most significant T2D signal in the heart atrial appendage and BMI signal in subcutaneous (SC) and visceral adipose. 3,960 eQTS were shared between T2D and BMI in the heart left ventricle (LV), and 68 were shared in SC adipose (all Q<0.05). Shared pathways in the heart were enriched for processes related to cellular respiration and heart contraction (Q<10-8). For CAD, cholesterol metabolism pathways were enriched in the coronary artery and visceral adipose (Q<10-2). In summary, T2D and BMI eQTS share mitochondrial and metabolic transcription mechanisms across several tissues, including SC adipose. Cholesterol metabolism was enriched in multiple tissues in CAD eQTS and also observed in T2D and BMI eQTS in visceral adipose. This study provides novel insight into the shared genetic and transcriptomic architecture of T2D, CAD, and obesity.

Disclosure

C. Bryan: None. K. Smith: None. A. Manning: None. J.M. Mercader: None. M. Udler: Other Relationship; Up-To-Date.

Funding

Doris Duke Clinical Scientist Development Award (2022063)
218-OR: Disrupted Circadian Glucocorticoid Rhythms and High-Fat Diet Drive Obesity and Insulin Resistance through Distinct Mechanisms
Authors: TERUEL MARY
Published: June 2024

Disrupted glucocorticoid (GC) rhythms, a hallmark of chronic stress and sleep dysregulation, are increasingly recognized as potential contributors to obesity and insulin resistance [1-3]. However, their impact compared to dietary factors remains unclear. Here we investigated the combined effects of high-fat diet (HFD) and disrupted GC rhythms on fat accumulation, metabolism, and lean mass in mice. Strikingly, we found that disrupted GC rhythms alone led to a doubling of adipose tissue mass within three weeks, comparable to HFD-fed mice, but without increased lipids in the liver or in circulating lipid and glucose levels. Mice with disrupted GC rhythms achieved a unique metabolic state of insulin resistance but surprisingly improved glucose tolerance. Mechanistically, we found this unique state was driven by persistent hyperinsulinemia to levels 10-fold higher than induced by HFD, despite persistently low glucose levels. The increase in insulin was driven by a rapid expansion of pancreatic beta cell mass and a shift towards cAMP-mediated insulin secretion. EchoMRI body composition measurements revealed a shift from lean-to-fat mass in GC-disrupted mice, resembling sarcopenic obesity. Our results demonstrate that disrupted GC rhythms can be just as potent as dietary excess in promoting fat mass gain. Furthermore, we found that disruption of GC rhythms and HFD increase fat mass through distinct and separable mechanisms, suggesting ways for effective personalized anti-obesity strategies that go beyond calorie restriction.

References:1. Bahrami-Nejad et al (2018). Cell Metabolism 27, 854-868.e8, 2. Luijten et al (2019). Cell Reports 27, 1686-1698. 3. Tholen et al (2022). Cell Reports 39, 111018.

Disclosure

M. Teruel: None.

Funding

National Institutes of Health (1-R01-DK131432)
225-OR: Sequential Islet Transplants for Type 1 Diabetes Do Not Cumulatively Increase Hepatic Portal Venous Pressure
Authors: CARR ALICE L.J. , SHAH RAHI , MARFIL-GARZA BRAULIO A. , LAM ANNA , ANDERSON BLAIRE L. , O'GORMAN DOUG , KIN TATSUYA , BIGAM DAVID , JAMES SHAPIRO A.M. , SENIOR PETER A.
Published: June 2024

The future of islet transplantation (ITx) is rapidly moving towards stem-cell based therapies, which have led to short term insulin independence when delivered into the hepatic portal vein. It is likely that multiple infusions will be needed to maintain insulin independence long term. We examined the effects of sequential ITx on portal pressures and if features of the transplanted preparation influence acute changes in portal pressure. We include data from adults undergoing intraportal ITx at the University of Alberta Hospital between May 1999 to April 2023. We assessed, by pairwise comparison, acute changes in portal pressure at each ITx infusion and used linear mixed-effects models to: 1) compare sequential pre-infusion portal pressure with reference to pre-first ITx infusion and 2) assess the relationship between change in portal pressure and packed cell volume (PCV), purity and islet equivalents per kilogram (IEQ/kg). We include 299 adults (44% M) who received up to 5 (median of 2 [IQR 2-3]) ITx infusions and a median total 15,220 IEQ/kg [IQR 11,324, 19,700]. The median purity across all ITx infusions was 55% [IQR 45, 70] with a median PCV of 3ml [IQR 2.5, 4]. The total time to final ITx was a median 11m [IQR 2-50]. Portal pressure acutely increased after each ITX infusion (p<0.001) by a median 2.0 mmHg [IQR 1.0-4.0]. This acute rise was not sustained however, with sequential pre-infusion portal pressure returning to similar levels (p>0.1) as that pre-first ITx infusion (median 11.0 mmHg [IQR 8.0-14.0]). PCV had the strongest correlation with post-infusion change in portal pressure, with a 1 mmHg increase in portal pressure per 1 ml of PCV (Slope: 1.09 [95% CI0.93,1.26]; p<0.001). Sequential ITx do not increase portal pressure or amplify changes during supplementary infusions. Higher PCV may exacerbate acute rises in portal pressures. Insights from deceased-donor intraportal ITx can inform safe implementation of future stem-cell based therapies in people living with diabetes.

Disclosure

A.L.J. Carr: None. R. Shah: None. B.A. Marfil-Garza: None. A. Lam: None. B.L. Anderson: None. D. O'Gorman: None. T. Kin: None. D. Bigam: None. A. Shapiro: Consultant; Vertex Pharmaceuticals Incorporated, Betalin Therapeutics, Hemostemix Inc, ViaCyte, Inc., Aspect Biosystems. P.A. Senior: Consultant; Abbott, Bayer Inc., Dexcom, Inc., Eli Lilly and Company, GlaxoSmithKline plc, Insulet Corporation, Novo Nordisk Canada Inc., Sanofi, Vertex Pharmaceuticals Incorporated. Speaker's Bureau; Abbott, Dexcom, Inc., Insulet Corporation, Novo Nordisk Canada Inc. Research Support; Novo Nordisk Canada Inc.
273-OR: Initial eQTL Discovery in Individual Pancreatic Cell Types from the Human Pancreas Analysis Program
Authors: WEIDEKAMP MARY A. , ELGAMAL RUTH , LORENZ KIMBERLY , KAESTNER KLAUS H. , GAULTON KYLE J. , GRANT STRUAN F. , VOIGHT BENJAMIN F.
Published: June 2024

The pancreas is composed of multiple, distinct cell types with etiologically relevant functions for diabetes. Pancreatic studies have collected data largely from bulk tissue, limiting the elucidation of how each pancreatic cell type contributes to disease. Single-cell technologies coupled to tissue collection efforts have expanded for the pancreas, facilitating novel characterization of genetics, expression, and regulation of these cell types at a population scale and across disease states. A leading effort generating this data, the Human Pancreas Analysis Program, aims to comprehensively study the human pancreas in diabetes and integrate data with the clinical history from de-identified donors. Data from this program provides an opportunity to investigate how each of the pancreas’ cell types uniquely contributes to metabolic traits. Here, we report an initial discovery effort to identify genetic variation associated with gene transcript abundance - i.e., expression quantitative trait loci (eQTL) - using 394,151 cells collected from single-cell RNA sequencing of 80 pancreatic donors. Clustering analysis of this data identified pancreatic islets, pancreatic exocrine cells and immune cell types. We initially focused on populations of alpha, beta and delta cells, which had sufficient cell numbers across donors. Using standard analysis pipelines, we observed 1,696, 1,744 and 946 significant eGenes in alpha, beta and delta cells (permutation p-value <0.05 and q-value <0.05), respectively. Formal colocalization with signals identified from a recent type 2 diabetes GWAS (Vujkovic et al, 2020) and our eQTL data identified 19 SNP-to-gene connections, all of which were unique to one of our identified cell types. One eGene, NCK1, has been previously investigated in beta cells, but our colocalization has implicated it in an alpha cell context. Future colocalizations and meta-analyses should improve nomination of putative effector transcripts underlying pancreatic disease.

Disclosure

M.A. Weidekamp: None. R. Elgamal: None. K. Lorenz: None. K.H. Kaestner: None. K.J. Gaulton: Consultant; Pfizer Inc. Stock/Shareholder; Neurocrine. S.F. Grant: None. B.F. Voight: None.

Funding

UM1 DK126194; T2D FGPU01 DK123594; HPAP-T2DU01 DK112217; HPAP-T1D
3-PUB: Prevalence and Associated Factors of Diabetic Retinopathy among Type 2 Diabetes in Beijing, China—A Cross-Sectional Study
Authors: WEI TIAN , ZHANG LIN , ZHU XIAO-RONG
Published: June 2024

Objective: Diabetic retinopathy (DR) is the main cause of blindness in diabetic patients. The worldwide prevalence of Diabetic Retinopathy was recently estimated to be 34.6%. However, the prevalence and contributing factors of diabetic retinopathy remains controversial in the study areas. The aim of this study was to assess the prevalence of diabetic retinopathy and associated factor among type 2 diabetic patients in Beijing, China.

Methods: Cross-sectional study of all type 2 DM patients who attended diabetic eye screeningin Dongcheng District of Beijing from November 2022 to July 2023. A total of 2151 diabetes successfully completed ophthalmological examinations. The risk factors of DR were evaluated by OR value and 95% confidence interval after Binary logistic regression was used to adjust age and sex. Using SPSS22.0 software (IBM, Armonk, NY, USA) for statistical analysis.

Results: There were 129 DR in patients with diabetes mellitus, the prevalence of DR is 6.0% in type 2 diabetes. To analyze the risk factors of retinopathy after adjusting the age and sex in the peoples with diabetes. Multivariate regression analysis showed that duration of diabetes (8years, OR=1.54, 95%CI:, 1.13-2.12, P<0.01), body mass index (BMI≥24kg/m2, OR=1.78, 95%CI:, 1.31-2.78, P=0.039), systolic blood pressure (per10mmHg, OR=1.13, 95%CI: increased; 1.03-1.24, P=0.012), Glycated hemoglobin ( OR=1.22, 95%CI:, 1.15-1.29, P<0.001) were independent risk factors of DR.

Conclusions: The prevalence of diabetic retinopathy in type 2 diabetes is 6.0%, which is significantly lower than that of most studies abroad and in China. The risk factors for diabetic retinopathy in type 2 diabetic people are the duration ofdiabetes, systolic pressure, body mass index and Glycated hemoglobin.These risk factors should be controlled for the prevention of complications in patients with type 2 diabetes.

Disclosure

T. Wei: None. L. Zhang: None. X. Zhu: None.

Funding

Beijing Municipal Science & Technology Commission(Z221100007422065)
304-OR: The Obesity-Related Natriuretic Handicap Involves the Coordinated Regulation of Multiple Genes in Adipose Tissue to Blunt Natriuretic Peptide Signaling
Authors: CEDDIA RYAN P. , BRITTAIN EVAN , MASHAYEKHI MONA , HUANG SHI , JONES RACHEL , PALACIOS JULIA , REYNOLDS CASSANDRA F. , MAMBUNGU CINDY , ALP IKIZLER T. , WANG THOMAS , COLLINS SHEILA , GUPTA DEEPAK , BACHMANN KATHERINE N.
Published: June 2024

Introduction & Objective: Obese individuals may experience a relative deficiency of natriuretic peptides (NP); this “NP handicap” may contribute to increased risks of hypertension, glucose intolerance, and fat accumulation in obesity. The pathogenesis of the NP handicap is not entirely known; elevated expression of the NP clearance receptor (NPRC) may contribute. We employ a comprehensive evaluation of the mechanisms underlying the NP handicap by measuring adipose gene expression of all 3 NP receptors, the peptidase neprilysin, and all cGMP degrading phosphodiesterases (PDE).

Methods: In a prospective study, we recruited 199 lean and obese adults (n = 55 lean, 144 obese; 56% female). We conducted biopsies of subcutaneous adipose tissue to measure gene expression and also measured circulating NP levels.

Results: Higher BMI was associated with lower circulating pro-Atrial NP and adipocyte gene expression of NPRA. Higher BMI was associated with higher adipose gene expression of proteins that degrade circulating NPs (NPRC, neprilysin) and blunt intracellular NP-evoked cGMP signaling (PDE 1A, 1C, 2A, 5A, 9A, 10A).

Conclusion: The obesity-related NP handicap is not only caused by upregulation of NPRC but appears to be a coordinated regulation of multiple genes in adipose tissue that work in concert to reduce NP signaling events.

Disclosure

R.P. Ceddia: None. E. Brittain: None. M. Mashayekhi: None. S. Huang: None. R. Jones: None. J. Palacios: None. C.F. Reynolds: None. C. Mambungu: None. T. Ikizler: None. T. Wang: None. S. Collins: None. D. Gupta: None. K.N. Bachmann: Employee; Amgen Inc. Stock/Shareholder; Medtronic, Pfizer Inc.

Funding

National Institutes of Health (HL145293, T32DK007061, UL1TR002243, KL2TR002245, DK020593, P30AI110527), U.S. Department of Veterans Affairs Clinical Sciences Research and Development (CSR&D) Program (IK2 CX001678), American Heart Association (17SFRN33520017), Vanderbilt Faculty Research Scholars, Vanderbilt Edge for Scholars Research Recovery fund
310-OR: Bacteremia and Endocarditis Complicating Moderate and Severe Diabetic Foot Infections
Authors: REYES MARIO C. , TARRICONE ARTHUR , PETERS EDGAR J. , ROGERS LEE C. , LAVERY LAWRENCE A.
Published: June 2024

Introduction & Objective: There are few published studies concerning blood stream infections (BSI) in diabetic foot infections (DFI). Our objective was to evaluate the incidence and risk factors for BSI and endocarditis in diabetic patients admitted to the hospital with moderate and severe DFI. Our secondary aim was to evaluate the correlation of blood cultures and intraoperative wound cultures.

Methodology: This was a meta-analysis with pooled patient level data from 3 RTCs. Moderate and severe infection was based on criteria of the International Working Group on the Diabetic Foot classification. BSI was defined as a positive blood culture upon admission. Endocarditis was diagnosed by echocardiogram. We compared isolates from blood cultures and intraoperative wound cultures. Concordance was defined as any single pathogen isolated in wound cultures also isolated from blood cultures. We used χ2 and t-test for comparison of clinical events, with alpha of <0.05.

Results: We evaluated 227 patients with blood cultures; (n=45) 19.8% had BSI. One (2.2%) patient had endocarditis. The concordance of wound cultures and blood culture pathogens was 66.7%. Polymicrobial infections were significantly more common in DFI vs BSI (48.7% vs 11.1%, p=<0.001)

Conclusion: The incidence of BSI in people with DFI is very high (19.8%). There is a high concordance of BSI and DFI bacterial pathogens.

Disclosure

M.C. Reyes: None. A. Tarricone: None. E.J. Peters: None. L.C. Rogers: None. L.A. Lavery: None.
340-OR: Transcriptional Activation in Beta-Cells during ER Stress Linking iPLA2beta with NFkB
Authors: LEI XIAOYONG , KUMAR CHALLA ANIL , TUSING YING , NAKAYASU ERNESTO , MIRMIRA RAGHAVENDRA G. , CHALFANT CHARLES E. , RAMANADHAM SASANKA
Published: June 2024

ER stress in β-cells has been reported to precede T1D development and we reported that the Ca2+-independent phospholipase A2β (iPLA2β) participates in ER stress-mediated β-cell apoptosis. Recently, we found that reduction in iPLA2β lowers T1D incidence. The iPLA2β hydrolyzes β-cell membrane glycerophospholipids to release arachidonic acid, which can be metabolized to inflammatory eicosanoids. Herein, we used insulinoma cells, human islets, spontaneously diabetes-prone NOD mice, and CRISPR-modified β-cells to address processes linking iPLA2β and ER stress. We find that cytokine-induced ER stress induces iPLA2β-mediated eicosanoid production, in association with NFκB activation and β-cell apoptosis. Surprisingly, inhibition or decreased iPLA2β expression also reduced NFκB activation at the transcriptional and protein levels. These observations were recapitulated in human and NOD.iPLA2β-/- islet β-cells and suggested potential regulatory links between iPLA2β and NFκB. To assess this at the molecular level, ChIP analyses were performed using MIN6 cells and not unexpectedly, an association between the transcription factor NFκB and PLA2G6, gene that encodes iPLA2β was observed. Intriguingly, ER stress also promoted association of iPLA2β with NF κ B and PLA2G6. Whereas inhibition of iPLA2β did not affect these associations, CRISPR-mediated reduction of iPLA2β significantly reduced both interactions. These observations suggest that iPLA2β protein itself, and not its lipid products, triggers transcriptional events to regulate its own production and that of apoptotic factors. Curiously, the iPLA2β protein is not recognized to have a DNA binding motif, therefore, suggesting that non-lipid co-factors likely link iPLA2β with target genes. Our findings identify a novel role for iPLA2β in modulating transcriptional events that are triggered during the development of ER stress, leading to β-cell death and T1D onset.

Disclosure

X. Lei: None. A. Challa: None. Y. Tusing: None. E. Nakayasu: None. R.G. Mirmira: None. C.E. Chalfant: None. S. Ramanadham: None.

Funding

NIH/NIDDK R01DK110292Beatson Foundation #2023-20UAB DRC P30 DK079626UAB Department of CDIBUAB Comprehensive Diabetes Center
353-OR: Chd3 Helicase Modulates Pancreatic ß-Cell Function in Absence of Chd4
Authors: KANOJIA SUKRATI , GEORGE RAJANI M. , OSMULSKI MEREDITH E. , DAVIDSON REBECCA K. , SANDOVAL KASSANDRA , HUTER KAYLA N. , SPAETH JASON
Published: June 2024

Pdx1, an essential transcription factor during β-cell development, controls expression of genes required to maintain β-cell function through selective recruitment of transcriptional coregulators. We recently found that Chd4, a helicase within the Nucleosome Remodeling and Deacetylase (NuRD) complex, interacts with and modulates Pdx1 transcriptional activity in β-cells, in part by controlling chromatin accessibility. This investigation revealed that removing Chd4 from mature β-cells (Chd4Δβ) led to increased levels of Chd3, an alternate helicase subunit of the NuRD complex. We uncovered that Pdx1 and Chd3 interact in the mature β-cell and their interactions are increased in Chd4Δβ β-cells, leading us to question whether Chd3 alone influences β-cell function or compensates in the absence of Chd4. We therefore generated mouse models with tamoxifen-inducible, β-cell-specific deletions of Chd3 (Chd3Δβ) and Chd3/Chd4 (Chd3/4Δβ). Four weeks following Chd3 removal, Chd3Δβ mice showed no changes in glucose homeostasis, whereas Chd3/4Δβ mutants exhibited severe glucose intolerance. Chd3/4Δβ mutants displayed elevated ad libitum fed blood glucose levels, reduced β-cell mass, and insulin release in response to glucose was severely compromised, indicating a much more severe phenotype than Chd4Δβ mutants. Further investigation revealed an increase in β-cell apoptosis and aberrant expression of glucagon in lineage labeled Chd3/4-deficient β-cells. These data suggest that Chd3 compensates for loss of Chd4, and loss of both subunits leads to β-cell demise and loss of identity. Future efforts are focused on evaluating gene expression and chromatin accessibility changes in Chd3/4Δβ β-cells and the impact the diabetes milieu has on Pdx1:Chd3 interaction in β-cells of T2D mouse models and human donors with T2D.

Disclosure

S. Kanojia: Employee; Eli Lilly and Company. R.M. George: None. M.E. Osmulski: None. R.K. Davidson: Employee; Eli Lilly and Company. K. Sandoval: None. K.N. Huter: None. J. Spaeth: None.
43-OR: Endothelial Cell Regeneration by Secretome Secreted from P53-Silenced Bone Marrow–Derived BMSCs
Authors: RAO NANDULA SESHAGIRI , ARGAW ABEL , SEN SABYASACHI
Published: June 2024

Diabetes is associated with impaired wound healing. Studies have demonstrated that endothelial progenitor cells (EPCs) and mature endothelial cells (EC) are susceptible to apoptosis in hyperglycemic environment and p53 gene silencing prevents cellular senescence and helps vascular regeneration. Previously we have shown that p53 silenced progenitor cell therapy helped tissue regeneration. Our goal is to test whether conditioned media obtained from p53 silenced human stem cells can also improve cellular regeneration.

Methods: Ad-human-P53 (TP53)-shRNA was used to silence P53 and Ad-scrambled-null-shRNA was used as control in bone marrow derived mesenchymal stromal cells. To collect conditioned mediaBM-MSCs were cultured in exosome free FBS media for 5 days, following transduction with Ad-p53sh or Ad-null, as the case may be. After transduction, cells were grown in media containing 2% exosome free FBS for only 48h and the collected supernatant was concentrated 10-fold to obtain the conditioned media (CM). Endothelial regeneration was tested using endothelial wound healing assay kit ( from Cell Biolabs # CBA-120-T).

Results: We compared CM obtained from null and p53sh in adipose and bone marrow derived mesenchymal stem cells on human endothelial cells in normal and high glucose conditions. Proliferation capacity of the p53sh CM was 2-3 fold more compared to null and non-transduced CM. The CM obtained from the untreated and null samples did not show increased proliferation in any of the cells tested. We are currently analyzing the secretome by mass spectroscopy.

Conclusion: P53 silencing appears to improve CM obtained from p53 silenced cells and may have therapeutic role in treating diabetes complications such as diabetic wound healing. [NSR1]is [NSR2]delete

Disclosure

S. Nandula: None. A. Argaw: None. S. Sen: None.
44-PUB: Electronic Health Record (EHR) Tools to Focus Care and Track Outcomes in a Community Health Worker Program (CHW) for Youth with Type 1 Diabetes
Authors: CRAVEN MEGHAN , TIMMONS KELLY D. , DEI-TUTU SELORM A. , BUTLER REBECCA , MARTINEZ AMELIA L. , JONES ADRINA , LYONS SARAH , SONABEND RONA Y. , DESALVO DANIEL
Published: June 2024

As part of our ROCKET T1D initiative (Remote Outreach & Care for Kids’ Empowerment and Technology use in T1D), we launched a CHW program to address social drivers of health (SDOH) in youth with T1D at high risk for DKA. Eligible patients are identified using the Risk Index for DKA (RI-DKA) and the CHW serves as an extension of the care team with a focus on 5 goals: improving communication, accessing healthy food, navigating barriers to diabetes technology, applying for public benefits, facilitating transition to adult care.

To enable focused CHW care, we leveraged EHR-based “Episodes of Care” as structure for setting goals, identifying needs/resources, and tracking outreach tasks. Episodes are groups of linked program encounters with the ability to demonstrate outcomes from enrollment to completion via discrete data fields. The SDOH tool allows the CHW to monitor progress over 5 domains (food insecurity, housing, transportation, education, financial resources). “Goal Setting” allows the CHW to set goals, track progress, and share this information with the patient. “Outreach Tasks” on the CHW dashboard are used to view upcoming outreach for active participants.

Our CHW program went live in fall 2023 and outcomes will be tracked on our enterprise data warehouse, which integrates clinical, operational, and financial megadata produced from multiple sources across our system.

Disclosure

M. Craven: None. K.D. Timmons: None. S.A. Dei-Tutu: None. R. Butler: None. A.L. Martinez: None. A. Jones: None. S. Lyons: None. R.Y. Sonabend: None. D. DeSalvo: Advisory Panel; Insulet Corporation. Consultant; Dexcom, Inc.

Funding

The Leona M. and Harry B. Helmsley Charitable Trust (2206-05307)
440-P: Influence of Sex on the Association between Vascular Endothelial Dysfunction and Plasma Leptin Levels in People with Type 2 Diabetes
Authors: MORIOKA TOMOAKI , NATSUKI YUKA , KAKUTANI YOSHINORI , YAMAZAKI YUKO , KURAJOH MASAFUMI , MORI KATSUHITO , SHOJI TETSUO , EMOTO MASANORI
Published: June 2024

Evidence from basic studies indicates that leptin, a key hormone in the regulation of food intake and energy expenditure, induces endothelium-dependent vasorelaxation. It is well known that plasma leptin levels of women are higher than those of men, however, the influence of sex on the relationship between vascular function and leptin remains unclear. In this study, we investigated the influence of sex on the relationship between plasma leptin levels and vascular endothelial dysfunction in people with type 2 diabetes (T2D). We included 337 Japanese people (195 men and 142 women) with T2D in this study. We measured flow-mediated dilatation (FMD) of the brachial artery to evaluate vascular endothelial function. Compared to women, men had lower leptin levels (the medians 2.6 vs. 7.6 ng/mL, p < 0.001) and lower FMD (the medians 5.6 vs. 6.4%, p = 0.044). Multivariate analysis revealed that plasma leptin levels in men were positively associated with FMD (β = 0.184, p = 0.034) independently of classical cardiovascular risk factors, such as age, BMI, HbA1c, eGFR, and serum phosphate levels. On the other hand, no association was found between serum leptin levels and FMD in women (β = 0.046, p = 0.662). Higher BMI and higher systolic blood pressure also showed an independent association with lower FMD in men, while only older age did in women. These data showed that there are sex differences in factors associated with FMD in people with T2D, and plasma leptin level is one of them. Considering the vasodilatory effect of leptin itself, this study suggests a functional relationship between low plasma leptin levels and vascular endothelial dysfunction in men with T2D.

Disclosure

T. Morioka: Research Support; Boehringer-Ingelheim, Eli Lilly and Company. Y. Natsuki: None. Y. Kakutani: None. Y. Yamazaki: None. M. Kurajoh: None. K. Mori: Speaker's Bureau; Mitsubishi Tanabe Pharma Corporation, Novo Nordisk, AstraZeneca, Lilly Diabetes, Kyowa Kirin Co., Ltd. T. Shoji: Speaker's Bureau; Kowa Company, Ltd., Bayer Inc., Ono Pharmaceutical Co., Ltd., Kyowa Kirin Co., Ltd. M. Emoto: Research Support; Boehringer-Ingelheim, Sumitomo Dainippon Pharma Co., Ltd., Mitsubishi Tanabe Pharma Corporation. Speaker's Bureau; Sumitomo Dainippon Pharma Co., Ltd., Kyowa Kirin Co., Ltd. Research Support; Chugai Pharmaceutical.
443-P: Association of Stiffness Parameter ß with Urinary Albumin Excretion Rather Than eGFR in Type 2 Diabetes
Authors: NAKATANI SUSUMU , KAKUTANI YOSHINORI , MORIOKA TOMOAKI , YAMAZAKI YUKO , OCHI AKINOBU , MORI KATSUHITO , SHOJI TETSUO , EMOTO MASANORI
Published: June 2024

Stiffness parameter β (stiffness β), a clinical estimate of arterial stiffness, increases with the progression of systemic atherosclerosis. Atherosclerosis is frequently and severely observed in patients with diabetic kidney disease (DKD) which is defined by decreased estimated glomerular filtration rate (eGFR) and/or elevated urinary albumin creatinine ratio (UACR). Both decreased eGFR and elevated UACR are known as risk factors of atherosclerosis. However, the contribution of each factor, eGFR or UACR, to arterial stiffness remains unclear. The present study aimed to investigate the association of eGFR or UACR with stiffness β in type 2 diabetes. Stiffness β was measured using ultrasonography at common carotid artery (CCA). The total 1,924 participants with type 2 diabetes including 58.8% of male were enrolled in this cross-sectional study. The mean age and HbA1c of all participants were 61.1 years and 8.6 %, respectively. The proportion of each CKD stage of eGFR (mL/min/1.73m2) and UACR (mg/g creatinine) were as follows: eGFR, 70.5% in G1/2 (≥ 60), 14.1% in G3a (45 - 60), 6.3% in G3b (30 - 45), and 9.0% in G4/5 (< 30); UACR, 61.5% in A1 (< 30), 20.3% in A2 (30 - 299), and 18.1% in A3 (≥ 300). Stiffness β (unitless) in G1/2, G3a, G3b, and G4/5 were 13.4 ± 5.8(SD), 15.0 ± 6.5, 16.1 ± 7.3, and 16.5 ± 7.4, respectively; and those in A1, A2, and A3 were 13.4 ± 5.9, 14.9 ± 6.1, and 15.8 ± 7.1, respectively. In univariate analysis, stiffness β was significantly correlated with both eGFR (r = −0.237, p < 0.001) or UACR (r = 0.161, p < 0.001). In multiple regression analyses, stiffness β was independently associated with UACR (β = 0.047, p = 0.043), but not with eGFR (β = −0.019, p = 0.439) after adjustment for classical risk factors.

In conclusion, stiffness β of CCA is associated with UACR, but not with eGFR, in patients with type 2 diabetes. Our findings suggest that stiffness β is more closely associated with UACR than eGFR in type 2 diabetes.

Disclosure

S. Nakatani: None. Y. Kakutani: None. T. Morioka: Research Support; Boehringer-Ingelheim, Eli Lilly and Company. Y. Yamazaki: None. A. Ochi: None. K. Mori: Speaker's Bureau; Mitsubishi Tanabe Pharma Corporation, Novo Nordisk, AstraZeneca, Lilly Diabetes, Kyowa Kirin Co., Ltd. T. Shoji: Speaker's Bureau; Kowa Company, Ltd., Bayer Inc., Ono Pharmaceutical Co., Ltd., Kyowa Kirin Co., Ltd. M. Emoto: Research Support; Boehringer-Ingelheim, Sumitomo Dainippon Pharma Co., Ltd., Mitsubishi Tanabe Pharma Corporation. Speaker's Bureau; Sumitomo Dainippon Pharma Co., Ltd., Kyowa Kirin Co., Ltd. Research Support; Chugai Pharmaceutical.
481-P: Gastroparesis Symptoms among Type 1 Diabetes Patients—Prevalence and Associated Factors
Authors: ALAMOUDI REEM , ALLUGMANI EBTESAM B. , ALSUDAIRY NAJLAA M. , ALSHAMRANI ABDULLAH A. , ALMUTAIRI MARAM F.
Published: June 2024

The development of gastroparesis-related symptoms in T1DM patients has major implications in the clinical course of the disease and physicians should be aware of the magnitude of the problem and its associated risks.

Objectives: To estimate the prevalence and identify predictors of gastroparesis in Saudi T1DM patients.

Methods: A cross-sectional study at King Abdulaziz Medical City Diabetes center, Jeddah, Saudi Arabia. All T1DM patients attending the endocrinology and diabetes clinics through Jan-Jun 2023 were approached. The Gastroparesis Cardinal Symptoms Index (GCSI) was utilized to diagnose gastroparesis.

Results: A total 113 T1DM patients were included. Age 12 - 54 (28.3 ±8.4) years. 63.7% were females, 26.5% overweight and 25.7% obese. Duration of diabetes 16.6 ±8 years, HbA1c% 8 ±1.5. Microvascular complications present in 24 (21.2%), 21.2% and 18.6% received statins and antihypertensives, and 12 (10.6%) were on metformin. Gastroparesis was present is 22 (19.5%). The most frequent reported symptoms were stomach fullness and feeling excessively full after meals (60.2%), followed by bloating (52.2%) and belly visibly larger (50.3%), whereas the lowest reported was vomiting (15.9%). Very severe form was reported in 9.7%. Multivariate logistic regression analysis revealed that females were at higher significant risk for developing gastroparesis compared to males (OR=4.36, 95% CI 1.15-16.56), p=0.031. Other studied factors (age, marital status, BMI, other chronic diseases, duration of diabetes, and microvascular complications) were not significantly associated with gastroparesis. HbA1c% was significantly higher in patients with gastroparesis compared to those without gastroparesis (8.9 ±1.9 versus 7.8 ±1.3), p=0.001. For every increase by one unit, the risk of developing gastroparesis increased by 59% (OR=1.59, 95% CI 1.16-2.19), p=0.004.

Conclusion: Gastroparesis symptoms are highly prevalent among Saudi T1DM patients and corollate with poor glycemic control.

Disclosure

R. Alamoudi: None. E.B. Allugmani: None. N.M. Alsudairy: None. A.A. Alshamrani: None. M.F. Almutairi: None.
536-P: Characteristics of People with Type 2 Diabetes Based on the Extended Parallel Processing Model (EPPM)
Authors: HU JIANLI , KIM SARAH , CHEN SOPHIA K. , ZISMAN-ILANI YAARA , SWAVELY DEBORAH A. , KELLY PATRICK J. , HOADLEY ARIEL , BASS SARAH B. , RUBIN DANIEL J.
Published: June 2024

A better understanding of perceived T2D threat and self-efficacy may inform improvements in self-management education. The EPPM was used to categorize 168 adults with T2D from urban safety-net clinics and the local community by self-efficacy and perceived threat from T2D. EPPM categories were high threat (HT)/high efficacy (HE), low threat (LT)/low efficacy (LE), HT/LE and LT/HE. Characteristics of participants with T2D (PwD) were compared within and between clinic and community settings across EPPM categories.

Among clinic PwD, HT/LE PwD had the lowest medication adherence (MARS-5) (p<0.001) vs other EPPM categories. Among community PwD, HT/LE PwD had the lowest T2D management scores (p<0.001) while LT/LE PwD had the lowest BMI (p<0.05). Demographics except age did not vary by EPPM category.

Compared to the community cohort, HT/LE PwD from clinics had higher health literacy (p<0.05), lower weight (p<0.05), lower BMI (p<0.01), and were more likely to be male (p<0.01) and use insulin (p<0.01). HT/HE PwD from clinics had higher MARS-5 scores (p<0.05), more microvascular complications (p<0.01) and were more likely to use statins (p<0.01).

The EPPM identified different subgroups within and between clinics and community settings. Differences in characteristics were mostly not attributable to demographics. The EPPM may be useful to tailor behavioral interventions to people with T2D in different settings.

Disclosure

J. Hu: None. S. Kim: None. S.K. Chen: None. Y. Zisman-Ilani: None. D.A. Swavely: None. P.J. Kelly: None. A. Hoadley: None. S.B. Bass: None. D.J. Rubin: None.

Funding

It was partially funded by the ADA Diabetes INSIDE program.
542-P: Does Intensive Type 2 Diabetes Care Management Improve Multiyear Mortality
Authors: MONTERO ALEX R. , NAM JOON , NASSAR CARINE M. , MAGEE MICHELLE F.
Published: June 2024

Introduction & Objective: The UKPDS Study demonstrated mortality benefit of pharmacologic interventions lowering A1C (NEJM 2008). Diabetes care management (DCM) in type 2 diabetes (T2D) has been shown to lower A1C but not studied mortality. Our aim was to assess mortality in adults with T2D and A1C >9% who had completed diabetes boot camp (DBC), an intensive 3-month DCM intervention (BMJ Open DRC 2019. doi: 10.1136/bmjdrc-2019-000731).

Methods: This retrospective cohort study compared mortality in DBC versus concurrent propensity matched controls. Kaplan Meier survival curves were constructed from time of DBC start. Follow up was ascertained via query of the data warehouse underlying our health system EMR. The most recent encounter date was assigned as censoring date when date of death was absent.

Results: All DBC participants (n=366) and controls (n=366) in the original cohort were included. Demographics, pre-post A1C and mortality outcomes are shown on table 1. At an average of 5.5 years of follow up, the overall mortality rate was 10% and not significantly different. In patients over 60 with A1C >= 12.0, DBC participants experienced borderline improved survival (p = 0.06 by Log-Rank test).

Conclusion: Participation in DBC, a DCM intervention, was not associated with an overall mortality benefit but older patients with markedly elevated A1C may have experienced improved survival compared to matched controls.

Disclosure

A.R. Montero: None. J. Nam: None. C.M. Nassar: None. M.F. Magee: Research Support; Medtronic. Other Relationship; Lilly Diabetes.
546-P: Impact of Virtual Patient Simulation on Improving Obesity Management With and Without Type 2 Diabetes by Primary Care Providers
Authors: LARKIN AMY , LE ANNE
Published: June 2024

Introduction: Impact of online, virtual patient simulation (VPS)-based continuing medical education (CME) on primary care physician (PCP) performance related to management of obesity in patients with and without T2D was assessed.

Methods: The VPS included two different patient scenarios. Tailored clinical guidance (CG) was shown after each clinical decision, followed by the opportunity to modify to their decisions. Data were collected post-CG and compared with each user’s baseline (pre-CG) using a McNemar’s test. Data collected March 2023 through June 2023.

Results: 624 PCPs were included. Case 1 (48 YO Obese Female with history of T2D, hypertension, and hyperlipidemia): Ordering tests: 13% absolute improvement (P<.001; baseline 40%); Making diagnoses: 33% absolute improvement (P<.001; baseline 0%); Ordering comprehensive treatment plans: 28% absolute improvement (P<.001; baseline 19%). Rationales for not prescribing therapy included not sure who to treat or when to use pharmacotherapy (41%), concerns with past obesity drugs (37%), and poor safety profiles (21%). Case 2 (55 YO obese male following-up on recent labs): Ordering tests: 10% absolute improvement (P<.001; baseline 42%); Making diagnoses: 38% absolute improvement (P<.001; baseline 26%); Ordering comprehensive treatment plans: 23% absolute improvement (P<.001; baseline 12%). Rationales for not prescribing therapy included not sure who to treat or when to use pharmacotherapy (39%), concerns with past obesity drugs (37%), and poor safety profiles (25%). Continued Gaps: Approximately half of PCPs have continued gaps in ordering tests to screen or monitor metabolic conditions, as well as making an obesity diagnosis. Over half of PCPs failed to comprehensively treat obesity.

Conclusion: VPS can improve evidence-based clinical decisions by PCPs related to comprehensive management of obesity in patients with and without T2D.

Disclosure

A. Larkin: None. A. Le: None.

Funding

Developed through an independent educational grant from Lilly.