bluuebunny/crossref_metadata_2025 huggingface dataset:
172-OR: Lineage Tracing of Vasculogenic Fibroblasts In Vivo and Their Significance in the Rescue of Diabetic Ischemic Tissue
Authors: SINGH KANHAIYA , VERMA SUMIT S. , ROY SASHWATI , SEN CHANDAN K. , KUMAR MANISHEKHAR
Published: June 2024

Our recent work reported on the identification of the vasculogenic fibroblast (VF) that is capable of generating new blood vessels during tissue repair (Pal et al. Nat Com, 2023). While these cells are physiologic and injury-inducible, the generation of VF is blunted under conditions of diabetes. Such barrier may be overcome by the inhibition of fibroblast miR-200b using tissue nanotransfection technology (PMIDs: 28785092, 34837085, 35819852, 36380587). To understand the mechanisms underlying VF function and significance, in this work we developed miR-200b-429fl/fl COL1A2creER GT(ROSA)mT/mG mice. In these mice, miR-200b regions in fibroblasts (COL1A2+ cells) are knocked out in response to tamoxifen. To gain insight into the significance of VF in vivo, ischemic hind limb studies were performed. Tamoxifen treatment not only led to Cre excision of miR-200b-429 in these mice, but also induced the constitutive expression of ROSA driven tdTomato in fibroblasts with onset of permanent GFP expression. Significant lowering of miR-200b was noted in laser capture dissected dermal fibroblast tissue elements from the wound-edge of tamoxifen treated mice (n=4). Tamoxifen treatment led to significantly enhanced perfusion in animals subjected to ischemic injury as determined by laser speckle perfusion imaging (Perimed Inc.) (n=8). This rescue was associated with increased abundance of GFP+CD31+ VF (n=5) which accounted for 26% of all CD31+ vascular cells in the laser captured blood vessels (n=9). Thus, targeted lowering of miR-200b abundance within fibroblasts resulted in substantial augmentation of VF in vivo which was associated with improved blood flow.

Disclosure

K. Singh: None. S.S. Verma: None. S. Roy: None. C.K. Sen: Consultant; SouthWest Technologies. Board Member; VisopalExo. Consultant; Vomaris Inc. M. Kumar: None.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (DK136814, DK128845, DK135447, DK125835); Department of Defense (W81XWH-21-1-0033, W81XWH-22-1-0146)
1724-P: DNA Damage Vulnerability of Immature Beta Cells
Authors: VARGHESE SNEHA S. , HERNANDEZ-DE LA PENA ALESSANDRO G. , BHATTACHARYA SUPRIYO , DHAWAN SANGEETA
Published: June 2024

Introduction & Objective: A healthy reserve of functional β-cells is crucial for maintaining glucose homeostasis and is disrupted in diabetes. Most of this reserve is established in early neonatal life via replication, following which β-cells exit cell-cycle and undergo functional maturation. Although the process of replication is extremely vulnerable to DNA damage and consequent genomic instability, the extent and impact of such vulnerabilities on β-cell maturation and subsequent viability is not clear. Here, we sought to determine the DNA damage vulnerability of replicating β-cells in the neonatal growth phase.

Methods: We quantified β-cell replication (Ki67, pHH3) and DNA damage (ɣH2AX) in early (p7) and late (p21) neonatal B6 mice (N=8 animals/ group). We acquired super-resolution 3D images of DNA damage foci and cohesins (modulators of genomic stability) in replicating β-cells using the Zeiss Elyra 7 Lattice SIM^2 and LSM880 with Airyscan, and analyzed using the Imaris software.

Results: Our data revealed that while the overall number of β-cells with DNA damage decreased as replication declined from p7 to p21, ~20% of replicating β-cells at each stage harbored DNA damage. Notably, the G2 phase had the highest density of DNA damage foci, which were resolved by the M phase. Single-cell RNA-seq of murine neonatal islets showed the enrichment of DNA damage repair pathways in replicating β-cells.

Conclusion: Collectively, our data establish the high DNA damage vulnerability of neonatal β-cells and suggest the existence of robust mechanisms that assist the resolution of DNA damage with cell cycle progression to maintain genomic stability.

Disclosure

S.S. Varghese: None. A.G. Hernandez-De La Pena: None. S. Bhattacharya: None. S. Dhawan: None.

Funding

Postdoctoral Fellowship from California Institute of Regenerative Medicine (EDU4-12772); NIH-National Institute of Diabetes and Digestive and Kidney Diseases (R01DK120523)
1748-P: NMDA Receptor Is Involved in Amplification Effects of Glycine on Insulin Secretion
Authors: WANG ZIWEI , MENG SHI , HAN DONGNA , LI CHANGHONG , ZHANG JUNQING
Published: June 2024

The NMDA receptor plays a crucial role in the central nervous system. Glutamate acts as its agonist, while glycine and D-serine play a co-agonist role. Recent studies have indicated that β-cells express the NMDA receptor, and it regulates insulin secretion, but the detailed mechanism is still unclear. Mouse islets were perifused in response to 10 mM glucose stimulation, a ramp of glutamate and glycine (0 to 10 mM) was administered either alone or on top of glucose. The ramp of glutamate and glycine alone have no effects on insulin secretion in perifused mouse islets. However, glycine ramp, not glutamate and D-serine ramp, can potentiate the 10 mM glucose-stimulated insulin secretion (GSIS). Glycine transporter 1, 2 and glycine receptor inhibitors, such as strychnine (5 µM), org25543 (10 µM), and the combination of org25543 (10 µM) and org24598 (10 µM), cannot block the potentiation effects of glycine to GSIS. The NMDA receptor inhibitor, MK801 (10 µM), enhanced the ability of glycine to augment GSIS, resulting in a leftward shift of the glycine amplification curve. Remarkably, D-serine and MK801 significantly enhanced the insulin secretion driven by 10 mM glucose, although glycine no longer exhibited its enhancing effects on GSIS. The synergistic effects of D-serine and MK801 on glucose ramp (0 to 25 mM) stimulated insulin secretion were examined. The combination resulted in an increase in the maximum insulin secretion induced by the glucose ramp, while the threshold remained unchanged. In vivo tests demonstrated that glycine improved glucose tolerance by increasing baseline insulin secretion. Our study has shown that glycine enhances GSIS through the involvement of the NMDA receptor pathway. In contrast to the central nervous system, the NMDA receptor in islets is no longer responsive to stimulation by glutamate. However, it still exhibits a robust response to glycine. While the NMDA receptor is present in islets, it may be regulated and sensed differently compared to the central nervous system.

Disclosure

Z. Wang: None. S. Meng: Employee; Nanjing Ascendrare Pharmaceutical Technology. D. Han: Employee; Nanjing Ascendrare Pharmaceutical Technology. C. Li: Employee; Hua Medicine (Shanghai) LTD., Nanjing AscendRare Pharmaceutical Technology. J. Zhang: None.

Funding

National Natural Science Foundation of China (81970701)
1749-P: Deficient Mitochondrial Activation in Type 2 Diabetic Human ß-Cells during Insulin Secretion
Authors: GERENCSER AKOS A.
Published: June 2024

Glucose and cellular energy metabolism are central components of glucose sensing in pancreatic β-cells. Conceptually, β-cells operate by converting the rate of glucose metabolism into the rate of insulin secretion. We have identified a novel activation mechanism in healthy human β-cell mitochondria that plays a central role in setting this rate of metabolism during glucose-stimulated insulin secretion (GSIS). Using live islets and dispersed islet cell cultures originating from type 2 diabetic (T2D) and nondiabetic human cadavers, here we show the failure of this activation mechanism and a loss of bioenergetic control in β-cells from T2D individuals. Modular kinetic analysis of oxidative phosphorylation was used to measure pathway activities based on monitoring cell respiration, mitochondrial membrane potential (ΔψM) and NADH/NAD+. We observed an energization-dependent activation of glucose oxidation during GSIS in nondiabetic β-cells, and localized this to intramitochondrial NADH-producing pathways, excluding Ca2+-dependent activation. In T2D β-cells the activation of this activation was impaired. Chronic culturing of nondiabetic β-cells at elevated glucose concentration or in the presence of methylglyoxal recapitulated the suppression of activation observed in T2D β-cells. In high glucose-cultured nondiabetic and in standard-cultured T2D β-cells the magnitude of GSIS was highly variable between individuals, and often increased. GSIS correlated well and was predicted by ΔψM in nondiabetic β-cells, but this bioenergetic fine control was lost in T2D suggesting a rearrangement of stimulus-secretion coupling in T2D, where the role energetics reduces to permissive, and other coupling pathways become dominant with kinetic properties different from nondiabetic.

Disclosure

A.A. Gerencser: None.

Funding

National Institutes of Health (R01DK135807)
175-OR: Level 3 Hypoglycemia in Diabetes—An Age-Old but Not (Just) Old-Age Problem (iNPHORM, USA)
Authors: RATZKI-LEEWING ALEXANDRIA , BLACK JASON E. , ZOU GUANGYONG , RYAN BRIDGET L. , HARRIS STEWART B.
Published: June 2024

Introduction & Objective: Whether advanced age increases Level 3 severe hypoglycemia (SH) rates remains surprisingly unresolved by research, despite its often-presumed association. Leveraging iNPHORM data, we aimed to address this gap.

Methods: Adults (≥18 y.o.) with T1DM or T2DM on insulin and/or secretagogues were recruited from a US-wide, probability-based internet panel. Prospective data were captured via an online screener, baseline, and 12 monthly follow-up questionnaires. For complete cases with ≥1 follow-up, we estimated the total (unadjusted) population-average effect of age on annualized Level 3 SH rates by diabetes type using negative binomial regression with generalized estimating equations. An interaction term tested subgroup effects by age <65 vs ≥65 y.o. (α=0.05).

Results: N=978 were analyzed (T1DM: 16.7%; male: 49.6%; retention rate: 80.1%). The mean age was 51.0 (SD:14.3) (T1DM: 44.6 [SD:13.8]; T2DM: 52.2 [SD:14.1]) years; 20.4% (T1DM: 9.8%; T2DM: 22.5%) were ≥65 y.o. Level 3 SH incidence proportions were 44.2% (≥65 y.o.: 43.8%) in T1DM, and 31.8% (≥65 y.o.: 16.4%) in T2DM. Rates were 3.6 events per person-year (EPPY) (≥65 y.o.: 2.0 EPPY) in T1DM, and 5.3 EPPY (≥65 y.o.: 0.8 EPPY) in T2DM. The interaction term (<65 vs ≥65 y.o.) was statistically significant for T1DM (p=0.03) and T2DM (p<0.001). In T1DM, a 5-year increase in age reduced Level 3 SH rates by 23% (95%CI: 16%-30%, p<0.001) for those <65 y.o., and increased rates by 51% (95%CI: -15%-170%, p=0.16) for those ≥65 y.o. In T2DM, event rates decreased by 41% (95%CI: 38%-43%, p<0.001) for those <65 y.o., and increased by 21% (95%CI: -7%-57%, p=0.15) for those ≥65 y.o.

Conclusion: Level 3 SH rates declined with age until 65 y.o., when rates began to increase. Our results emphasize the need for age-specific hypoglycemia prevention. Clinical efforts should address the impact of advancing age among older adults, particularly those with T1DM; yet interventions targeting young adults, especially with T2DM, should not be overlooked.

Disclosure

A. Ratzki-Leewing: Research Support; Sanofi. Advisory Panel; Dexcom, Inc. Consultant; Abbott. Advisory Panel; Sanofi-Aventis U.S. Other Relationship; American Diabetes Association. Consultant; Novo Nordisk, Eli Lilly and Company. J.E. Black: None. G. Zou: None. B.L. Ryan: None. S.B. Harris: Consultant; Abbott. Research Support; Boehringer-Ingelheim. Consultant; Dexcom, Inc. Advisory Panel; Eli Lilly and Company. Consultant; Eli Lilly and Company, Novo Nordisk, Sanofi. Research Support; Novartis AG. Consultant; Bayer Inc.

Funding

The iNPHORM study was funded through an investigator-initiated grant from Sanofi Global.
1756-P: Dynorphin Expression in Beta-Cells—Insights into Regulation
Authors: MOVAHED MIRANDA , BLANDINO-ROSANO MANUEL
Published: June 2024

The expression of dynorphin within beta-cells, an endogenous opioid peptide predominantly expressed in the CNS and involved in stress response, pain, and addiction, has intrigued researchers for over two decades. Yet, its functional implications in islet physiology remain incompletely elucidated. Genetically, the Pdyn gene is prominently upregulated in beta-cells under high-fat diet conditions and in human beta-cells affected by Type 2 Diabetes, emphasizing its potential relevance in metabolic disorders. This comprehensive investigation elucidates the regulatory mechanisms and developmental dynamics of dynorphin within this specific subset of beta-cells. Our investigation revealed a developmental progression in dynorphin expression, with undetectable levels at birth gradually escalating with advancing age. Notably, dynorphin expression was heterogeneous within beta-cells, manifesting in approximately 15% of beta-cells at two months. In vitro studies show that an increase in glucose levels notably correlates with increased dynorphin expression specifically in beta-cells already expressing dynorphin, unveiling a critical interplay where cAMP, Ca2+ and Creb signaling cascades emerge as pivotal regulators governing dynorphin expression within this subset of beta-cells. Furthermore, our findings show the synergistic effect of palmitate in conjunction with high glucose, amplifying dynorphin levels in these specific beta-cells expressing dynorphin. This selective interaction underscores the complex interrelationship between nutrient exposure and dynorphin expression, offering intriguing insights into the responses of a subset of beta-cells to diverse dietary components.

Disclosure

M. Movahed: None. M. Blandino-Rosano: None.

Funding

1R01DK132095
1760-P: The Role of Branched-Chain Amino Acids in Augmenting Insulin Secretion in Human Islets at Different Glucose Concentrations
Authors: HOR CHENG KOH , CHAN JAMES C.Y.
Published: June 2024

Nutrient sensing is an important feature of pancreatic islets to manage glucose homeostasis. Islets are highly responsive to glucose yet are significantly less sensitive to individual amino acids. Conversely, combinations of ingested amino acids may augment insulin secretion when given with glucose. We explored the insulinotropic effect of different amino acid combinations when co-administered with low (3 mM) and high (11 m) glucose levels.

Batch incubations were performed with islets from healthy and lean (BMI < 25 kg/m2) Caucasians. Islets were starved at 3 mM glucose before being sequentially treated with amino acids in conjunction with low and high glucose, followed by KCl. Insulin secretion was analysed using ELISA and normalized by islet equivalent (IEQ) counts.

When BCAA is given with low glucose, insulin secretion significantly increases, comparable to high glucose alone. When given with high glucose, BCAA had no insulinotropic effects. Other combinations did not result in a significant increase in insulin secretion at both low and high glucose. In summary, our data examines the insulinotropic effect of different amino acid combinations at high and low glucose respectively, representing fasted and fed states.

Disclosure

K. Hor Cheng: None. J.C.Y. Chan: None.
1762-P: The Dynamic Role of PPAR-γ and Related Pathways in Beta Cells during Type 2 Diabetes Mellitus Progression
Authors: XIAO YU , SHI JIANXIANG , ADAMA MAHARANA PRATHAP R. , KIM GRACE J. , WELCH MEGHAN , JIANG YINAN
Published: June 2024

Type 2 Diabetes (T2D) is characterized by peripheral insulin resistance, deteriorating beta-cell function and eventual beta-cell failure. The role of Peroxisome proliferator-activated receptor γ (PPAR-γ) in beta-cells, as opposed to its role in peripheral cells in glucose metabolism, is not well understood during T2D progression. Here, we utilized S961, a specific insulin receptor inhibitor, to induce glucose intolerance and hyperglycemia in mice, thereby simulating the stages of T2D progression. Using beta-cell-specific knockouts of PPAR-γ, WNT5A and SMAD7, we explored the molecular mechanisms through which PPAR-γ and related signaling pathways affect beta-cell proliferation, insulin secretion, and dysfunction in T2D. Our results indicated an initial increase in PPAR-γ expression in beta-cells of pre-diabetic patients, followed by a reduction in diabetic patients. In mice, PPAR-γ expression in beta-cells rose after 7 days of S961 treatment (paralleling pre-diabetic conditions) but fell after 14 days (reflecting diabetic conditions). Conversely, SMAD7 levels in beta-cells were stably minimal initially but increased in later stages in both mice and diabetic patients. Assisted with single-cell RNA sequencing, we found that S961-treated mice experienced an upregulation in the TGF-β signaling cascade in beta-cells, leading to the activation of pSMAD3, which subsequently upregulated PPAR-γ, enhancing beta-cell proliferation and secretion. However, prolonged S961 exposure and the direct effects of hyperglycemia augmented SMAD7 levels, which inhibited SMAD signaling, resulting in reduced PPAR-γ, compromised beta-cell functionality and the onset of diabetes. This late upregulation of SMAD7 was likely mediated through WNT5A/Smarf2/ubiquitin signaling, which was progressively altered during T2D progression. Our findings underscore the intricate interplay of PPAR-γ and related pathways in beta-cells during T2D pathogenesis.

Disclosure

Y. Xiao: None. J. Shi: None. M.R. Adama: None. G.J. Kim: None. M. Welch: None. Y. Jiang: None.

Funding

Internal grants
1769-P: Empowering Islet Biology—Advancing Scientific Rigor and Reproducibility, Resource Discoveries, and Effective AI/ML Collaboration via dkNET
Authors: CHEN SHUIBING
Published: June 2024

The NIDDK Information Network (dkNET; dknet.org) is an open community resource for researchers supported by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), including islet biology investigators. The primary objective is to provide tools, access to diverse resources, and training modules to foster scientific rigor and reproducibility, and collaboration among researchers. dkNET offers various services such as Resource Reports for finding resources and tracking the use and performance of resources (antibodies, model organisms, cell lines, plasmids, biosamples, software tools, and protocols) through the use of Research Resource Identifiers (RRIDs); FAIR Data Resources that provide guidance to meet NIH’s most recent data management and sharing mandates; and the Hypothesis Center that provides tutorials enabling researchers to utilize online datasets and analytics and visualization tools. Building on its success, dkNET is extending its services to provide Artificial Intelligence (AI)/Machine Learning (ML) techniques and cloud computing resources to the NIDDK research community to fully leverage data assets cataloged by dkNET to explore and develop hypotheses. A successful pilot use case, powered by Texera, has been developed to apply machine learning tools to identify the key factors controlling aging of human endocrine cells.

Disclosure

S. Chen: None.

Funding

NIH NIDDK (U24DK09777)
1770-P: Gymnemic Acid Functions as NFE2L2 Activator to Enhance Antioxidant Defense against Cellular Stress Caused by Inflammation and Hypoxia in Human Pancreatic Islets
Authors: KUNCHA JAYACHANDRA , DARDEN CARLY , KIRKLAND JEFFREY , MATTKE JORDAN D. , LAWRENCE MICHAEL C. , NAZIRUDDIN BASHOO
Published: June 2024

Introduction & Objective: Increasing the mass of pancreatic beta cells through neogenesis and proliferation while protecting islets from oxidative stress and inflammation is a possible therapeutic strategy for treating all types of diabetes. We examined the effect of the natural phytocompound Gymnemic Acid I (GA) on human pancreatic islets to reduce oxidative stress and inflammation.

Methods: Human pancreatic islets were exposed to various stress-induced, well-established models like hypoxia and cytokine cocktails (CC) with or without GA. Flow cytometry, Luminex assay, and RT-qPCR techniques were used to assess the oxidative stress and inflammatory markers. All the results were statistically compared with appropriate experimental controls.

Results: Treatment with GA maintained islet viability for >24 h and significantly increased (P<0.024) insulin secretion assessed by GSIS and substantially (P<0.05) upregulated beta-cell functional genes (PCSK1, SLC2A, GCK). Reactive oxygen species (ROS), hypoxia, and CC-induced cell death were all substantially reduced by GA treatment. Additionally, inflammatory, pro-apoptotic genes (HIF1A, CCL5, IL-6, INFb1, IP10, CASP3) and secretory cytokine production were considerably (P<0.05) downregulated. It protected the islets by making it easier for the transcription factor NFE2L2 to bind ARE which in turn led to a significant (P<0.05) upregulation of promotor regions encoding cytoprotective and antioxidant genes (HOMOX1, SOD1, CAT, NQO1, BCL2).

Conclusion: GA functions as an NFE2L2 activator or stabilizer, protecting and extending the viability of islets. It has improved islet function by boosting endogenous antioxidant defense enzymes, preventing oxidative damage and apoptosis in response to cellular stress driven by inflammation, hypoxia, or both. GA can serve as a treatment for improving human islet survival and function.

Disclosure

J. Kuncha: None. C. Darden: None. J. Kirkland: None. J.D. Mattke: None. M.C. Lawrence: None. B. Naziruddin: None.
1779-LB: Hospitalization for Hypoglycemia and Its Risk Factors among Patients with Diabetes and Cognitive Impairment
Authors: TANG HUILIN , LU YING , DONAHOO WILLIAM T. , DEKOSKY STEVEN T. , BIAN JIANG , GUO JINGCHUAN
Published: June 2024

Introduction: Hypoglycemia is the most common serious adverse effect of diabetes treatments and a major cause of hospitalization, with an increased risk in the presence of cognitive impairment. This study aimed to identify risk factors associated with hospitalization for hypoglycemia in patients with diabetes and cognitive impairment.

Methods: Using 2012-2020 electronic health records data from University of Florida Health, we included patients with diabetes and cognitive impairment aged ≥50 years. The outcome was the first occurrence of hospitalization for hypoglycemia. Baseline variables include demographics, comorbidities, and comedications. Multivariate logistic regression was employed to calculate the adjusted odds ratio (AOR) and 95% confidence interval (CI) of hospitalization for hypoglycemia associated with baseline risk factors.

Results: This study included 3,263 patients diagnosed with both diabetes and cognitive impairment, with a mean age of 71.8 years. Female and non-Hispanic Black population accounted for 55.8% and 36.1%, respectively. In a median follow-up period of 1.95 years (Interquartile range, 0.97-3.55), 12.6% (410 patients) experienced hospitalization for hypoglycemia. Compared with those with HbA1c of 7-7.9%, the AOR of hospitalization for hypoglycemia was 0.64 (95% CI 0.34-1.19), 0.89 (0.52-1.52), 2.19 (1.20-3.98), and 2.26 (1.24-4.10) among those with HbA1c <6, 6-6.9, 8-8.9, and ≥9%, respectively, in the multivariable logistic regression model. Additionally, prior hypoglycemia (AOR, 5.58, 95%CI, 2.67-11.67), chronic kidney disease (1.65; 1.08-2.53), and insulin use (2.25; 1.37-3.70) were independent risk factors for hospitalization for hypoglycemia.

Conclusion: We identified several risk factors associated with hospitalization for hypoglycemia among patients with diabetes and cognitive impairment, offering insights into the identification of high-risk patients and potential preventive strategies.

Disclosure

H. Tang: None. Y. Lu: None. W.T. Donahoo: None. S.T. DeKosky: Advisory Panel; Acumen Pharmaceuticals, Cognition Therapeutics. Consultant; Eisai Inc., Novo Nordisk. Other Relationship; Prevail Pharmaceuticals, Vaccinex. Consultant; Biogen. Advisory Panel; Otsuka America Pharmaceutical, Inc. J. Bian: None. J. Guo: None.
1782-LB: Treatment Efficacy of Diabetic Kidney Disease with a Novel Specific Cathepsin L Inhibitor
Authors: ZHAO MIAOMIAO , LI MING-JIA , LI XIAO-YA , YANG JIN-KUI
Published: June 2024

Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease (ESKD), yet there are no specific drugs for DKD. In previous research, we found that the lysosomal enzyme Cathepsin L (CTSL) is upregulated in diabetic patients, and high glucose levels can activate CTSL protein function (eLife, accepted). We also discovered the important role and mechanism of CTSL in COVID-19 infection (PMID: 33774649, 35668062). Previous studies have shown that CTSL activation can lead to podocyte fusion and detachment, resulting in proteinuria. Broad-spectrum cathepsin inhibitors protect renal function in animals and prevent proteinuria. However, current cathepsin inhibitors have non-specific targets and result in significant side effects, making them unsuitable for human use. Here, we developed a novel CTSL inhibitor (US Patent No: US11858905B1) that specifically targets CTSL without significant side effects. We confirmed in db/db mice (with early-stage DKD phenotype) and BKS-db-eNos-/- mice (with late-stage DKD phenotype) that: 1. Acute administration for 3 days at a dose of 1000mg/kg showed no significant toxicity; chronic administration for 16 weeks at a dose of 20mg/kg showed no significant toxicity and reduced the mice’s water and food intake. 2. Chronic administration for 16 weeks improved markers of kidney damage in db/db mice and BKS-db-eNos-/- mice, such as urine albumin creatine ratio, urine NGAL creatine ratio, and urine Kim-1 creatine ratio. 3. Pathological results showed a significant reduction in glomerular volume, renal interstitial inflammation, and PASM staining indicated a significant improvement in glomerular sclerosis with the use of the novel CTSL inhibitor. Masson staining suggested a significant improvement in renal interstitial fibrosis with the CTSL inhibitor. Our study demonstrates the significant improvement in diabetic kidney disease treatment with the novel CTSL inhibitor.

Disclosure

M. Zhao: None. M. Li: None. X. Li: None. J. Yang: None.
1785-LB: Potential Noninvasive Markers Predicting Diabetic Kidney Disease Development
Authors: WU JIANBO
Published: June 2024

Introduction: Diabetic kidney disease (DKD) is one common microvascular complication of diabetes. When the kidney is damaged, it may communicate abnormally with cells in the blood system. Renipuncture is invasive and traumatic for patients, and a noninvasive panel that predicting DKD occurrence or progression needs to be identified.

Method: The single-cell RNA sequencing (scRNA-seq) dataset (GSE183279) comprise kidney samples from normal individuals (n=18) and patients with DKD (n=12). The bulk RNA sequencing (RNA-seq) dataset (GSE96804) consist of renal glomerular tissue samples from normal individuals (n=20) and DKD patients (n=41). The proteomics data (PXD047872) include serum samples from normal, diabetic mellitus, early-stage and late-stage diabetic nephropathy. In brief, we utilize "Seurat" package in R (version 4.3.1) to analyze the scRNA-seq data, Tensor-cell2cell to identify intercellular communication, and ClusterGVis package to extract protein expression matrices.

Results: By integrating bulk-seq and scRNA-seq, we have identified 5 critical receptor-ligand pairs and 17 hub genes, emphasizing the vital role of integrin-mediated cell interactions in DKD's pathogenesis. By Integrating the serum protein data and scRNA-seq, we have identified 7 significantly upregulated proteins and 3 significantly downregulated proteins in DKD group.

Conclusion: These findings set a foundation for future clinical applications. We will verify these markers in clinical samples and confirm their functions for the kidney in the future.

Disclosure

J. Wu: None.

Funding

This research was funded by National Natural Science Foundation project (82370823, 82370356); Beijing Tongzhou District Science and Technology Plan Project (JCQN2023001, KJ2023SS011).
1787-LB: Pathological Characteristics of Ferroptosis in Diabetic Kidney Disease
Authors: LI MIN , ZHOU YARU , GAO QIAN
Published: June 2024

Introduction & Objective: Diabetes kidney disease (DKD) is common complication of diabetes and it is currently considered as the primary cause of end-stage renal disease. Ferroptosis is a newly defined regulatory cell death caused by iron-dependent lipid peroxidation, and it plays a key role in the development of DKD. This study was aimed to examine in vivo the involvement of ferroptosis in diabetes-related pathological changes in the kidney.

Methods: 30 DKD patients diagnosed with renal tissue pathology from the Third Hospital of Hebei Medical University and 10 healthy controls were selected for H&E, PASM staining, and immunohistochemical staining to evaluate pathological changes such as renal inflammation and fibrosis, as well as changes in the expression of iron death related proteins; At the same time, general statistical data and clinical test data of each group of patients were collected, and further logistic regression analysis and receiver operating characteristic curve (ROC) analysis were performed to explore independent risk factors and diagnostic efficacy of DKD.

Results: The expressions of iron death-related proteins GPX4, ACSL4, FTH and FTL were increased in renal tissues of DKD patients, while the expressions of Nrf2 and TfR1 were decreased.And the expression levels of Nrf2 and ACSL4 proteins in kidney tissue are influential factors for the occurrence of DKD, and have high diagnostic efficacy for DKD.

Conclusion: The current study showed that ferroptosis contributes to diabetes-related pathological changes in the kidney, and we demonstrated that ferroptosis was involved in the development of DKD.

Disclosure

M. Li: None. Y. Zhou: None. Q. Gao: None.

Funding

Project of Hebei Provincial Health Commission (20230093)
1798-LB: STK25 Promotes Diabetic Atherosclerotic Plaque Formation via Septin2 Regulating Mitophagy
Authors: WANG DI , WANG LU , WANG YAN , YANG LONGYAN
Published: June 2024

Introduction & Objective: Serine/Threonine protein kinase 25 (STK25) was reported to regulate lipid accumulation and activation of inflammatory and fibrotic pathways as well as oxidative and endoplasmic reticulum stress in human aortic endothelial cell. However, the direct substrate of STK25 in endothelial cells is not clear, and the mechanism of STK25 and its substrate in the diabetic atherosclerosis remained unknown. This study aimed to explore the substrate and potential mechanism of STK25 in the formation of diabetic atherosclerotic plaque.

Method: Male C57BL/6J mice were intraperitoneal injection of streptozotocin and tail-vein injection of the rAAV8-PCSK9 virus (5 ×1010 genome copies) or negative control to establish an diabetic atherosclerosis model. Thereafter, mice were fed a western-type diet. Morphological observation, blood triglyceride and cholesterol analysis, oil red O staining, immunofluorescent staining, electron microscope, real-time PCR, co-immunoprecipitation, and Western Blot were performed. Human aortic endothelial cells subjected to different concentrations of low density lipoprotein (LDL) was applied for assessing the related mechanism.

Result: STK25 increased, the endothelial barrier function was impaired, and mitophagy of aortic endothelial cells decreased in vivo and in vitro. While the silencing of STK25 reduces lipid accumulation and improve the mitophagy in aortic endothelial cells. And LC/MS and Co-IP showed that Septin2 had interaction with STK25. Moreover, STK25 regulates mitophagy of endothelial cell through phosphorylation of Septin2.

Conclusion: Together, we provide several lines of evidence that STK25 promoted diabetic atherosclerotic plaque formation, which is accounted for at least partly via septin2 regulating mitophagy.

Disclosure

D. Wang: None. L. Wang: None. Y. Wang: None. L. Yang: None.

Funding

Beijing Luhe Hospital Capital Medical University, Youth Research Incubation Project (LHYY2023-JC207)
180-OR: Glycemic Markers Are Differentially Associated with Cardiovascular Imaging and Outcomes in Long-Duration Type 1 Diabetes
Authors: GREGORY YU MARC , VISHVA TEJA JANGOLLA SURYA , ZIEMNIAK NOLAN A. , VIEBRANZ ELIZABETH R. , SHAH HETAL , KING GEORGE L.
Published: June 2024

Cardiovascular disease (CVD) is a major cause of mortality in type 1 diabetes (T1D). While glycemic control is related to CVD outcomes in T1D, there is a lack of information on the risk of glycemic excursions and comparative contributions of glycemic markers to CVD in aging populations with T1D. Among the Joslin “Medalists” with T1D≥50 years (n=1043), mean historical HbA1c was obtained across longitudinal visits (median 4.1 years), while a single consecutive 14-day block of continuous glucose monitoring (CGM) data was remotely obtained from a subset of Medalist CGM users (n=110). Additionally, Medalists underwent coronary artery calcification scans (CAC; n=153) and cardiac magnetic resonance imaging of left ventricular (LV) structure and function (CMR; n=111). In the overall cohort, HbA1c was associated with CVD (p<0.001). CGM metrics for hyperglycemia (mean glucose, p=0.03; glucose management indicator, p=0.03; and time above range>180 mg/dL, p=0.02), but not hypoglycemia or day-to-day glycemic variability, were associated with LV remodeling. Plasma assays for advanced glycation end-products (AGEs; n=200), N-carboxyethyl-lysine (CEL), N-carboxymethyl-lysine (CML), and methylglyoxal-derived hydroimidazolone (MGH1), showed associations with CVD (p=0.04, p=0.04, and p=0.01, respectively); CAC (p=0.05, p=0.01, and p=0.01, respectively); and LV remodeling (p=0.09, p=0.05, and p=0.04, respectively). The association of CEL with CVD replicated in a separate Medalist subset (n=311) with self-reported CVD data (p=0.01). These findings indicated that glycemic parameters assessing long-term, irreversible markers of hyperglycemia (AGEs) are the strongest drivers of CVD in people with long-duration T1D, as compared to hypoglycemia or day-to-day glycemic variability. Our results highlight the need for glycemic control in aging populations with T1D, even after other risk factors like hyperlipidemia and hypertension have been controlled.

Disclosure

M. Yu: None. S. Jangolla: None. N.A. Ziemniak: None. E.R. Viebranz: None. H. Shah: None. G.L. King: None.

Funding

American Diabetes Association (9-18-CVD1-005); Mary K. Iacocca FoundationThomas J. Beatson Foundation; National Heart, Lung, and Blood Institute (R01 HL161864-02)
1800-LB: Reprogramming of Macrophage Metabolism by Pyruvate Dehydrogenase Attenuates Atherosclerosis through Mitigation of iNOS-Induced Foam Cell Formation
Authors: JEON JAE-HAN , KIM MI-KYUNG , LEE IN-KYU
Published: June 2024

Background: Prior transcriptomic analyses have illuminated a correlation between the upregulation of glycolysis, induced by oxidized low-density lipoprotein (ox-LDL), and the extent of foam cell formation. This study aimed to elucidate the impact of metabolic redirection via pyruvate dehydrogenase complex (PDH) in macrophages on the formation of foam cells and the progression of atherosclerosis.

Methods: We employed a mouse model wherein bone marrow cells from either wild-type or PDK 2/4-knockout mice were transplanted into lethally irradiated LDL receptor-deficient (LDLR-/-) mice, which were subsequently maintained on a Western diet (WD) for 18 weeks. Additionally, bone marrow-derived macrophages (BMDMs) were isolated, treated with a PDK inhibitor, and then stimulated with ox-LDL for 24 hours.

Results: Evaluation of atherosclerotic lesions via Oil-Red-O staining demonstrated that mice transplanted with PDK2/4-deficient bone marrow and fed a WD exhibited a reduction in plaque formation. The administration of the PDK inhibitor curtailed ox-LDL-induced M1 macrophage polarization, as evidenced by decreased Nos2 expression, alongside a notable reduction in nitric oxide production by the treated BMDMs.

Conclusion: Modulation of macrophage metabolism through PDH activation can mitigate atherosclerosis by inhibiting iNOS-induced foam cell formation. These observations underscore the potential of targeting PDK as a therapeutic strategy for atherosclerosis.

Disclosure

J. Jeon: None. M. Kim: None. I. Lee: None.
1803-LB: Improving Diabetic Foot Ulcer Management with Electrochemical Skin Conductance
Authors: VITTRANT BENJAMIN , GAUTIER JEAN-FRANÇOIS , RIVELINE JEAN-PIERRE , POTIER LOUIS , BOURRON OLIVIER , BRUNSWICK PHILIPPE , BAUDUCEAU BERNARD , DEVILLE KARINE , CRITON ALINE
Published: June 2024

Introduction: Addressing the challenges in diabetic foot ulcer (DFU) management is critical, given the high morbidity, mortality, and healthcare costs associated with this devastating complication of diabetes. This study introduces an innovative strategy for DFU risk stratification using Electrochemical Skin Conductance (ESC) measurements from the Sudoscan device. It is a quick, non-invasive, painless, reproducible technique that does not require fasting or stopping treatment.

Methods: The study involved 2157 diabetic patients from four French hospitals, evaluating the association between ESC measures and DFU risk stratification scores based on 10g monofilament testing.

Results: Multivariate analysis affirmed the association, independently of others covariate (age, sex), between the ESC and the DFU grades. ROC curve analysis demonstrated good predictive power for DFU grades 3, 2, and 1 (AUC=0.82/0.62/0.62.) but revealed limitations for grade 0 (AUC=0.34) due to the wide range of ESC values. Heatmap analysis showcased ESC's granularity within low-grade patients, suggesting potential subgroups not captured by the standard grading system.

Conclusion: With a quantifiable association between ESC measures and high DFU grades while revealing differences for low DFU grade, this approach offers an avenue for improving precision in risk assessment at early and reversible diabetic peripheral neuropathy stages therefore fostering early clinical intervention.

Healthcare Equity: The standardized and objective nature of ESC measurements while having a low cost contributes to more equitable healthcare delivery. By reducing disparities in risk identification, this approach ensures consistent and accurate assessments, regardless of geographical location or healthcare provider.

Disclosure

B. Vittrant: Employee; Withings. J. Gautier: Board Member; Sanofi. Other Relationship; Sanofi. Speaker's Bureau; AstraZeneca, Novo Nordisk. Research Support; Novo Nordisk. Advisory Panel; Pfizer Inc. J. Riveline: Board Member; Abbott, Novo Nordisk A/S, Sanofi, Eli Lilly and Company, Medtronic, Dexcom, Inc., Insulet Corporation, Air Liquide, AstraZeneca. L. Potier: Research Support; Abbott. Consultant; AstraZeneca, Bayer Inc., Eli Lilly and Company, Novo Nordisk, Sanofi, Boehringer-Ingelheim. O. Bourron: Speaker's Bureau; Novo Nordisk, Sanofi, Lilly Diabetes, AstraZeneca, Bayer Inc. Research Support; Withings. P. Brunswick: Consultant; Impeto medical. B. Bauduceau: Consultant; Lilly Diabetes, Boehringer-Ingelheim, AstraZeneca. A. Criton: Employee; Withings.
1805-LB: Attenuation of Niacin-Induced Skin Flushing Response—A Potential Clinical Adjunctive Diagnostic Instrument for Diabetic Peripheral Neuropathy
Authors: JIANG TIANYUAN , LIU FANG
Published: June 2024

Objectives: Explore the potential of using niacin-induced skin flushing response (NSFR) as a diagnostic method for diabetic peripheral neuropathy (DPN) based on the microangiopathic characteristics of DPN.

Methods: This study involved 114 diabetic patients (51 with DPN, 59 without DPN, and 4 with an undetermined diagnosis) and 91 healthy controls(HC). DPN was assessed through clinical symptoms and/or signs, quantitative sensory tests, and electromyography. NSFR is detected using a modified 6-chamber sandwich patch and six different concentrations of aqueous methyl nicotinate (AMN). The sum of the 6 AMN concentrations' flushing area scores within 10 minutes after reaction were calculated and defined as the total NSFR score.

Results: NSFR to gradient concentration stimulation of AMN is reduced and delayed in diabetes patients compared to HCs, and the total NSFR score was significantly decreased (6827.3 (5038.45) vs. 10680 (5060.2)mm2, P < 0.001). The decline in NSFR was more pronounced in diabetes patients with DPN compared to those without DPN (4517.9 (3909.3) vs. 8896.5 (5179.7)mm2, P < 0.001). The association between NSFR and diabetic neuropathy was further evaluated using a multinomial logistic regression model. After adjusting for covariates that might affect NSFR or neuropathy (including age, sex, diabetes duration, BMI, fasting C-peptide, and HbA1c), NSFR was still independently associated with diabetic neuropathy (odds ratio: 0.903 (95% CI: 0.843-0.968), P=0.004). The optimal cut-off point of total NSFR score to distinguish diabetic neuropathy from non-diabetic neuropathy was 8530mm2, with a sensitivity of 88.2% and a specificity of 49.2%.

Conclusions: NSFR reduction is closely and independently associated with the existence of peripheral neuropathy in diabetic patients, and has great potential as an auxiliary tool in diagnosing diabetic peripheral neuropathy.

Disclosure

T. Jiang: None. F. Liu: None.

Funding

National Natural Science Foundation of China (82170827); Natural Science Foundation of Shanghai Science and Technology Commission(22ZR1450100); Shanghai Science and Technology Innovation Action Plan - Yangtze River Delta Region Collaboration Project(22002400600)
1812-LB: Association of Plasma Ceramides with Progression to Diabetes in the Diabetes Prevention Program (DPP) and Outcomes Study (DPPOS)
Authors: ASUZU PEACE , STENTZ FRANKIE B. , WAN JIM Y. , MANDAL NAWAJES , DAGOGO-JACK SAMUEL , PREVENTION PROGRAM RESEARCH GROUP DIABETES
Published: June 2024

Objective: Ceramides (CER) have been implicated in the pathogenesis of type 2 diabetes (T2D). Here, we assessed baseline plasma CER profiles in relation to incident T2D in the DPP/DPPOS.

Methods: Adults at high risk for T2D were randomized in DPP to intensive lifestyle, metformin, or placebo to compare their effects on diabetes incidence, and followed long-term in DPPOS. For this DPP ancillary study, we evaluated 198 randomly selected participants from the DPP placebo group, comprising 100 who had progressed to T2D (P) by DPPOS Year 11 (~15 years after randomization) and 98 non-progressors (NP), frequency matched by sex, age group and race/ethnicity. Plasma levels of 30 CER species, including 10 monohexosylceramides (MHC) and 10 lactosylceramides (LAC), were assayed in DPP baseline specimens using LC-MS/MS.

Results: At DPP baseline, mean (+ SD) age (51.6 + 8.5 y vs 51.4 + 9.0 y), BMI (34.5 + 7.7 kg/m2 vs. 34.1 + 6. 1 kg/m2), waist circumference, lipids, hsCRP and adiponectin levels were similar, but fasting plasma glucose (FPG) (110 + 8.8 mg/dl vs 104 + 6.3 mg/dl, P<0.0001) and 2-hour plasma glucose (2hPG) (167+ 15.8 mg/dl vs 160 + 16.4 mg/dl, P=0.0007) were higher in P vs. NP. Baseline levels of total CER, long-chain CER C20:0 - C26:0 and MHC C22:0 were higher, and LAC C18:0, C20:0 and C26:1 were lower, in P vs. NP, adjusted for age, race, sex, BMI, FPG and 2hPG (P’s = 0.02 to <0.0001). The ratios of CER C26:0/C26:1 (P=0.005) and MHC C24:0/C24:1 (P= 0.008) were higher in P vs. NP. In logistic regression models, baseline plasma ratios of CER C26:0/C26:1 predicted incident T2D: OR 1.26 per 0.1 unit, 95% CI 1.09-1.49, P=0.004, adjusted for baseline age, race, sex, BMI, FPG, and 2hPG

Conclusion: Higher baseline plasma levels of long-chain CER and MHC, and lower levels of LAC, were associated with incident T2D during ~15 years of follow-up in the DPP/DPPOS. The saturated-to-unsaturated CER C26:0/C26:1 ratio is a potential biomarker of incident T2D risk among individuals with pre-diabetes.

Disclosure

P. Asuzu: None. F.B. Stentz: None. J.Y. Wan: None. N. Mandal: None. S. Dagogo-Jack: Consultant; Merck Sharp & Dohme Corp., Medtronic, Bayer Inc. Stock/Shareholder; Aerami.
1817-LB: Association between the Neutrophil Percentage–to–Albumin Ratio and Mortality in Patients with Diabetic Foot Ulcer
Authors: ZHU HONG
Published: June 2024

Objective: Diabetic foot ulcer (DFU) is a common complication of diabetes mellitus, and it is also the main cause of infection, hospitalization, amputation and even death in patients with DFU. Neutrophil percentage-to-albumin ratio (NPAR) has been proved to be a predictor of death in many diseases. The aim of this study is to investigate the relationship between NPAR and mortality in patients with DFU.

Methods: This study included 1719 participants with DFU. The cutoff value of NPAR was determined according to the receiver operating characteristic (ROC) curve, and then the patients were divided into two groups: low NPAR group and high NPAR group. Cox proportional hazard regression was used to evaluate the association between NPAR and the risk of death in DFU patients. The difference in survival between groups was evaluated using Kaplan-Meier analysis and the log-rank test. Subgroup analyses were performed to determine whether there were differences in the effects of NPAR in different subgroups.

Results: The median age of all participants was 68 years old, and 61.1% of participants were males. By the end of follow-up, a total of 715 patients with DFU died. Patients with higher NPAR exhibited a significantly lower overall survival rate (P <0.001). The median survival in lower NPAR group is 119 months, compared to only 69 months in the high NPAR group. In multivariate Cox regression analysis, higher NPAR was an independent risk factor in patients with DFU compared with lower NPAR [adjusted hazard ratio (HR): 1.56; 95% confidence interval (CI): 1.29 - 1.89, P <0.001]. There was no statistically significant interaction between NPAR and any of the other DFU risk variables in the subgroup analysis. Conclusions NPAR is an independent predictor of the risk of mortality in patients with DFU. Higher NPAR is associated with increased mortality.

Keywords: Percentage of neutrophils; Albumin; Diabetic foot ulcer; Mortality

Disclosure

H. Zhu: None.
1819-LB: A Health Communication Assessment of Oral Self-Care Contents in Web-Based Education Materials for People with Diabetes
Authors: ZHANG YUQING , BERGER KIMBERLY , LEVEILLE SUZANNE
Published: June 2024

Introduction & Objective: Periodontal disease is the most prevalent diabetes complication affecting more than half of the diabetes population. However, it is unclear to what extent oral self-care recommendations have been incorporated into diabetes patient education websites, and, if available, how clear these are for patients to prevent and control oral complications of diabetes. This study aimed to evaluate availability and clarity of web-based oral self-care content for people with diabetes (PWD).

Methods: Google and Bing searches with keywords, “diabetes information for patients”, “living with diabetes”, and “diabetes self-management”, were performed. The first three pages of search results were reviewed excluding sponsored websites. We examined publicly available health information websites linked to major medical centers, health systems or government agencies, and excluded commercial websites. We assessed oral health information webpages for clarity and actionability using the CDC’s Community Communication Index (CCI).

Results: After eliminating duplicates, 52 diabetes education websites were assessed. Two-thirds had no information about oral health and one-fifth included minimal content such as statements about need for regular dental checkups. Seven websites had full pages on oral health information and were assessed using the CCI, with an average score of 77 (Range 64-88).

Conclusion: Although there are many websites providing patient education information on diabetes, only one-third include information about oral health. There is great need for reliable, accessible, and easy to use web-based patient education material to improve oral health awareness and behaviors, equipping PWD with the necessary knowledge and skills to practice optimal oral self-care.

Disclosure

Y. Zhang: None. K. Berger: None. S. Leveille: None.

Funding

American Diabetes Association (ADA 11-22-JDFHD-06)