Higher Insulin Research Articles

The association of objective daytime sleepiness with impaired glucose metabolism in patients with obstructive sleep apnea: a multi-omics study.

To examine the joint effect of obstructive sleep apnea (OSA) and objective excessive daytime sleepiness (EDS) on glucose metabolism and the underlying mechanisms. We included 127 patients with OSA. The multiple sleep latency test (MSLT) and Epworth sleepiness scale (ESS) were used to assess objective and subjective EDS, respectively. Disordered glucose metabolism was defined as either a physician diagnosis or having fasting blood glucose levels ≥ 5.6 mmol/L. Values of fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) higher than the median values of our sample were defined as high fasting insulin and insulin resistance. Serum metabolomics and fecal microbiota were used to explore underlying mechanisms. Lower MSLT values were associated with higher levels of fasting blood glucose, fasting insulin, and HOMA-IR. Furthermore, objective EDS was associated with increased odds of disordered glucose metabolism, elevated fasting insulin, and insulin resistance. Dysregulation of serum valine degradation and dysbiosis of fecal Bacteroides thetaiotaomicron were associated with impaired glucose metabolism in OSA with objective EDS. No association between subjective EDS and impaired glucose metabolism was observed. OSA with objective, but not subjective, EDS is associated with an increased risk of disordered glucose metabolism and insulin resistance. Dysregulation of valine degradation and dysbiosis of Bacteroides thetaiotaomicron appear to link objective EDS and disordered glucose metabolism in OSA.

Bioinspired orthogonal-shaped protein-biometal nanocrystals enable oral protein absorption.

With the growing number of marketed biological drugs, the development of technological strategies for their oral systemic absorption, becomes increasingly important. The harsh gastrointestinal environment and low permeability of the intestinal epithelium, represent a huge challenge for their systemic delivery. Herein, bioinspired in the physiological insulin-Zn interaction, the design of orthogonal-shaped protein-biometal hybrid nanocrystals, further enveloped by a bilayer of functional biomaterials, is reported. The nanocrystals exhibited a size of 80 nm, a neutral surface charge and a high insulin loading. In vitro studies showed the capacity of the nanocomplexes to control the release of the associated insulin, while preserving its stability. In vivo evaluation showed sustained blood glucose reductions in both healthy and diabetic rats (up to 40 % and 80 %, respectively), while chronic immunotoxicity studies in mice indicated no toxicity effect. Preliminary efficacy studies in healthy awake pigs following oral capsule administration showed over 20 % absolute bioavailability.

Associations of physiologic subtypes based on HOMA2 indices of β-cell function and insulin sensitivity with the risk of kidney function decline, cardiovascular disease, and all-cause mortality from the 4C study

BackgroundPrevious studies have been limited by their inability to differentiate between the effects of insulin sensitivity and β-cell function on the risk of kidney function decline, cardiovascular disease (CVD), and all-cause mortality. To address this knowledge gap, we aimed to investigate whether the physiological subtypes based on homeostasis model assessment-2 (HOMA2) indices of β-cell function (HOMA2-B) and insulin sensitivity (HOMA2-S) could be used to identify individuals with subsequently high or low of clinical outcome risk.MethodsThis retrospective cohort study included 7,317 participants with a follow-up of up to 5 years. Based on HOMA2 indices, participants were categorized into four physiologic subtypes: the normal phenotype (high insulin sensitivity and high β-cell function), the insulinopenic phenotype (high insulin sensitivity and low β-cell function), the hyperinsulinaemic phenotype (low insulin sensitivity and high β-cell function), and the classical phenotype (low insulin sensitivity and low β-cell function). The outcomes included kidney function decline, CVD events (fatal and nonfatal), and all-cause mortality. Cox regression models were used to calculate hazard ratios (HRs) for outcomes, and spline models were used to examine the dose-dependent associations of HOMA2-B and HOMA2-S with outcomes.ResultsA total of 1,488 (20.3%) were classified as normal, 2,179 (29.8%) as insulinopenic, 2,173 (29.7%) as hyperinsulinemic, and 1,477 (20.2%) as classical subtypes. Compared with other physiological subtypes, the classical subtype presented the highest risk of kidney function decline (classical vs. normal HR 11.50, 95% CI 4.31–30.67). The hyperinsulinemic subtype had the highest risk of CVD and all-cause mortality (hyperinsulinemic vs. normal: fatal CVD, HR 6.56, 95% CI 3.09–13.92; all-cause mortality, HR 4.56, 95% CI 2.97–7.00). Spline analyses indicated the dose-dependent associations of HOMA2-B and HOMA2-S with outcomes.ConclusionsThe classical subtype had the strongest correlation with the risk of kidney function decline, and the hyperinsulinemic subtype had the highest risk of CVD and all-cause mortality, which should be considered for interventions with precision medicine.Graphical abstract

The effect of the endothelin receptor antagonist atrasentan on insulin resistance in phenotypic clusters of patients with type 2 diabetes and chronic kidney disease.

Type 2 diabetes (T2D) patients with a clinical phenotype characterized by a high degree of insulin resistance are at increased risk of chronic kidney disease (CKD). We previously demonstrated that the endothelin receptor antagonist (ERA) atrasentan reduced insulin resistance in T2D. In this study, we compared the effect of atrasentan on insulin resistance across different phenotypic clusters of patients with T2D. We performed a post hoc analysis of the SONAR trial, a randomized, placebo-controlled trial of the ERA atrasentan in patients with T2D and CKD. Patients were stratified into four previously identified phenotypic clusters: severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD), mild obesity-related diabetes (MOD) and mild age-related diabetes (MARD). Changes in insulin resistance, assessed by HOMA-IR, were compared between the phenotypic clusters using a mixed effects model. In total, 931 patients were included in the analysis. In the overall population, atrasentan compared to placebo reduced HOMA-IR by 12.9% [95%CI 3.5,21.4]. This effect of atrasentan was more pronounced in clusters characterized by insulin resistance or deficiency: (SIRD cluster 26.2% [95% CI 3.8,43.3] and SIDD cluster 18.5% [95%CI -3.8,35.9]), although the latter did not reach statistical significance. The effect of atrasentan compared to placebo was less pronounced in the other two clusters (MARD 12.2% [95% CI -1.7,24.12] and MOD -5.3% [95% CI -28.9,13.9]). Atrasentan significantly improved insulin sensitivity in patients with T2D and CKD, especially in those characterized by high insulin resistance (SIRD cluster). Further studies are warranted to investigate the long-term clinical outcomes of atrasentan treatment in these distinct phenotypic clusters.

Study on the Mechanism of Raspberry (Rubi fructus)in Treating Type 2 Diabetes Based on UPLC-Q-Exactive Orbitrap MS, Network Pharmacology, and Experimental Validation.

The aim of this study is to analyze the chemical composition of raspberry using liquid chromatography-mass spectrometry (LC-MS) technology, predict the potential effects of raspberry in treating type 2 diabetes through network pharmacology, and conduct preliminary validation through invitro experiments. A Waters CORTECS C18 column (3.0 mm × 100 mm, 2.7 μm) was used; mobile phase A consisted of 0.1% formic acid in water and mobile phase B consisted of 0.1% formic acid in acetonitrile. Gradient elution was performed with full-scan mode in both positive and negative ion modes, covering a mass range of m/z 100-1500. The chemical components of raspberry were analyzed and identified based on secondary spectra from databases and relevant literature. The disease targets related to type 2 diabetes were searched, and protein-protein interaction network analysis as well as gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted on the intersecting targets of the active components of raspberry and the disease. HepG2 cells were used for experimental validation, with high glucose-induced insulin resistance models established. The CCK-8 method was employed to assess the effects of raspberry on cell proliferation, while Western blotting was used to measure the expression of proteins related to the AGE/RAGE signaling pathway. A total of 47 components were identified, including 10 organic acids, 15 flavonoids, 12 phenols, 2 alkaloids, 4 terpenoids, 1 miscellaneous compound, 1 stilbene, 1 steroid and its derivatives, and 1 diterpenoid. Through database screening, seven active components were identified: kaempferol, epicatechin, ellagic acid, crocetin, stigmasterol, fisetin, and isorhamnetin. KEGG and GO results indicated that the therapeutic effects of raspberry on type 2 diabetes may be related to the advanced glycation end product (AGE)- receptor for advanced glycation end product (RAGE) signaling pathway. Establishment of an insulin resistance model in HepG2 cells demonstrated that, compared to the control group, the raspberry treatment group upregulated p53 protein expression while downregulating the expression of RAGE, Akt1, and Caspase-3 proteins. This study preliminarily elucidates that the therapeutic effects of raspberry in treating type 2 diabetes may be mediated through the inhibition of the AGE-RAGE signaling pathway, providing important references for the study of the pharmacological basis and clinical application of raspberry.

Impaired suppression of fatty acid release by insulin is a strong predictor of reduced whole-body insulin-mediated glucose uptake and skeletal muscle insulin receptor activation.

To examine factors underlying why most, but not all, adults with obesity exhibit impaired insulin-mediated glucose uptake, we compared: (1) adipose tissue fatty acid (FA) release, (2) skeletal muscle lipid droplet (LD) characteristics, and (3) insulin signalling events, in skeletal muscle of adults with obesity with relatively high versus low insulin-mediated glucose uptake. Seventeen adults with obesity (BMI: 36 ± 3 kg/m2) completed a 2 h hyperinsulinemic-euglycemic clamp with stable isotope tracer infusions to measure glucose rate of disappearance (glucose Rd) and FA rate of appearance (FA Ra). Skeletal muscle biopsies were collected at baseline and 30 min into the insulin infusion. Participants were stratified into HIGH (n = 7) and LOW (n = 10) insulin sensitivity cohorts by their glucose Rd during the hyperinsulinemic clamp (LOW< 400; HIGH >550 nmol/kgFFM/min/[μU/mL]). Insulin-mediated suppression of FA Ra was lower in LOW compared with HIGH (p < 0.01). In skeletal muscle, total intramyocellular lipid content did not differ between cohorts. However, the size of LDs in the subsarcolemmal region (SS) of type II muscle fibres was larger in LOW compared with HIGH (p = 0.01). Additionally, insulin receptor-β (IRβ) interactions with regulatory proteins CD36 and Fyn were lower in LOW versus HIGH (p < 0.01), which aligned with attenuated insulin-mediated Tyr phosphorylation of IRβ and downstream insulin-signalling proteins in LOW. Collectively, reduced ability for insulin to suppress FA mobilization, with accompanying modifications in intramyocellular LD size and distribution, and diminished IRβ interaction with key regulatory proteins may be key contributors to impaired insulin-mediated glucose uptake commonly found in adults with obesity.

Rare variation in LMNA underlies polycystic ovary syndrome (PCOS) pathogenesis in two independent cohorts.

Polycystic ovary syndrome (PCOS) is a common, heritable endocrinopathy that is a common cause of anovulatory infertility in reproductive age women. Variants in LMNA cause partial lipodystrophy, a syndrome with overlapping features to PCOS. We tested the hypothesis that rare variation in LMNA contributes to PCOS pathogenesis and selects a lipodystrophy-like subtype of PCOS. We sequenced LMNA by targeted sequencing a discovery cohort of 811 PCOS patients and 164 healthy controls. We then analyzed LMNA from whole-exome sequencing (WES) of a replication cohort of 718 PCOS patients and 281 healthy controls. Variation in the LMNA gene, hormone and lipid profiles of participants. In the discovery cohort, we identified 8 missense variants in 15/811 cases, and 1 variant in 1/172 reproductively healthy controls. There is strong evidence for association between the variants and PCOS compared to gnomAD non-Finnish European population controls (χ2=17, p=3.7x10-5, OR=2.9). In the replication cohort, we identified 11 unique variants in 15/718 cases, and 1 variant in 281 reproductively healthy controls. Again, there is strong evidence for association with population controls (χ2=30.5, p=3.4x10-8, OR= 4.0). In both the discovery and replication cohorts, variants in LMNA identify women with PCOS with high triglycerides and extreme insulin resistance. Rare missense variation in LMNA is reproducibly associated with PCOS and identifies some individuals with lipodystrophy-like features. The overlap between this PCOS phenotype and genetic partial lipodystrophy syndromes warrants further investigation into additional lipodystrophy genes and their potential in PCOS etiology.

Liver magnetic resonance imaging, non-alcoholic fatty liver disease and metabolic syndrome risk in pre-pubertal Mexican boys.

Rising global pediatric obesity rates, increase non-alcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS) prevalence, with MetS being a NAFLD risk factor. NAFLD can be asymptomatic, with liver function tests insensitive to mild disease, and liver biopsy, risking complications. Thus, we investigated multiparametric MRI (mpMRI) metrics of liver fat (proton density fat fraction, PDFF) and disease activity (fibro-inflammation; iron-corrected T1, cT1), in a Hispanic pre-pubertal pediatric cohort, with increased risk of NAFLD. Pre-pubertal boys (n = 81) of varying Body-Mass Index (BMI) were recruited in Mexico City. Most children (81%) had normal liver transaminase levels, 38% had high BMI, and 14% had ≥ 3 MetS risk factors. Applying mpMRI thresholds, 12%, 7% and 4% of the cohort had NAFLD, NASH and high-risk NASH respectively. Participants with ≥ 3 MetS risk factors had higher cT1 (834ms vs. 737ms, p = 0.004) and PDFF (8.7% vs. 2.2%, p < 0.001) compared to those without risk factors. Those with elevated cT1 tended to have high BMI and high insulin (p = 0.005), HOMA-IR (p = 0.005) and leptin (p < 0.001). The significant association of increased risk of MetS with abnormal mpMRI, particularly cT1, proposes the potential of using mpMRI for routine pediatric NAFLD screening of high-risk (high BMI, high MetS risk score) populations.

Decreased Insulin and Interleukin-6 Levels in Rattus Norvegicus Model of Polycystic Ovary Syndrome-Insulin Resistance Treated with a High Protein Diet

Hypercaloric in women of childbearing age is one of the causes of polycystic ovary syndrome (PCOS) with insulin resistance. Increased inflammation (tumor factor necrosis-α (TNF-α) and interleukin-6 (IL-6)) is the impact of endocrine and metabolic disorders involved due to metabolic syndrome, obesity, and diabetes mellitus. This study aims to evaluate whether a high-protein diet can reduce insulin and interleukin-6 levels, which are key indicators of polycystic ovary syndrome, and whether these changes can help in the treatment of the syndrome. This study used a prepost test only control design, true experimental, with a total sample of 6 female Rattus norvegicus rats aged 2–3 years (150–200 g). It consists of 4 groups, namely the negative control group (K-), the positive control group (K+), the treatment group (P), and the group without treatment (P-). The study examined the rat blood serum ELISA measurement of insulin and IL-6 levels. Anova test results of IL-6 levels (p = 0.002). Post-hoc test results of group K- and group P (p = 0.002), group K + and group P (p = 0.037), group K- and group K + (p = 0.437). The Anova test results of insulin levels between groups found a significant difference (p = 0.001). Post-hoc test of insulin levels of group K- and group P (p = 0.002), group K- and group K+ (p = 0.000), and group K+ with group P (p = 0.356). In group K and group P, the results of the ANOVA and post hoc tests on IL-6 levels and insulin levels with the provision of a high-protein diet show significant differences. This study suggests that a high-protein diet may be an effective therapeutic alternative in reducing the symptoms of polycystic ovary syndrome, especially in controlling high insulin and interleukin-6 levels.

The Potential of Dehydrated Geniotrigona thoracica Stingless Bee Honey against Metabolic Syndrome in Rats Induced by a High-Carbohydrate, High-Fat Diet

Background/Objectives: Metabolic syndrome (MS) is diagnosed when at least three out of five key risk factors are present: obesity, high blood pressure, insulin resistance, high triglycerides (TG) and low high-density lipoprotein (HDL). MS is often associated with chronic low-grade inflammation. Recent studies have shown that raw stingless bee honey (SBH) can alleviate MS risk factors. However, the high moisture content in raw SBH predisposes it to fermentation, which can degrade its quality. Therefore, dehydrating SBH is necessary to prevent the fermentation process. This study aimed to compare the effects of dehydrated (DeGT) and raw (RGT) SBH from Geniotrigona thoracica species on high-carbohydrate, high-fat diet (HCHF)-induced MS in rats. Methods: Twenty-four male Wistar rats were divided into four groups: control (C), HCHF-induced MS without treatment (MS), HCHF-induced MS treated with DeGT (MS+DeGT) and HCHF-induced MS treated with RGT (MS+RGT). Group C received standard rat chow, while the other groups were fed with HCHF diet for 16 weeks. In the final eight weeks, two HCHF-induced groups received their respective SBH treatments. Results: Both DeGT and RGT treatments reduced energy intake, fat mass, high blood pressure, inflammatory (tumour necrosis factor-alpha (TNF-α)) and obesity (the leptin/adiponectin (L/A) ratio, corticosterone, 11 beta-hydroxysteroid dehydrogenase type-1 (11βHSD1)) markers, as well as prevented histomorphometry changes (prevented adipocyte hypertrophy, increased the Bowman’s space area and glomerular atrophy). Additionally, DeGT increased serum HDL levels, while RGT reduced serum TG, leptin and other inflammatory markers (interleukin-6 (IL-6) and interleukin-1 beta (IL-1β)), as well as hepatosteatosis. Conclusions: While DeGT demonstrates potential as a preventive agent for MS, RGT exhibited more pronounced anti-MS effects in this study.

MCM proteins are up-regulated in placentas of women with reduced insulin sensitivity.

In the first trimester of pregnancy the human placenta grows rapidly, making it sensitive to changes in the intrauterine environment. To test whether exposure to an environment in utero often associated with obesity modifies placental proteome and function, we performed untargeted proteomics (LC-MS/MS) in placentas from 19 women (gestational age 35-48 days, i.e. 5+0-6+6 weeks). Maternal clinical traits (body mass index, leptin, glucose, C-peptide and insulin sensitivity) and gestational age were recorded. DNA replication and cell cycle pathways were enriched in the proteome of placentas of women with low maternal insulin sensitivity. Driving these pathways were the minichromosome maintenance (MCM) proteins MCM2, MCM3, MCM4, MCM5, MCM6 and MCM7 (MCM-complex). These proteins are part of the pre-replicative complex and participate in DNA damage repair. Indeed, MCM6 and γH2AX (DNA-damage marker) protein levels correlated in first trimester placental tissue (r = 0.514, P<0.01). MCM6 and γH2AX co-localized to nuclei of villous cytotrophoblast cells, the proliferative cell type of the placenta, suggesting increased DNA damage in this cell type. To mimic key features of the intrauterine obesogenic environment, a first trimester trophoblast cell line, i.e., ACH-3P, was exposed to high insulin (10 nM) or low oxygen tension (2.5% O2). There was a significant correlation between MCM6 and γH2AX protein levels, but these were independent of insulin or oxygen exposure. These findings show that chronic exposure in utero to reduced maternal insulin sensitivity during early pregnancy induces changes in the early first trimester placental proteome. Pathways related to DNA replication, cell cycle and DNA damage repair appear especially sensitive to such an in utero environment.

Efeitos da atividade física em crianças e adolescentes com síndrome metabólica: uma revisão sistemática

Introduction: evidence demonstrates that regular physical exercise has beneficial effects in the prevention and treatment of high blood pressure, insulin resistance, diabetes, dyslipidemia and obesity in the population. Objective: To evaluate the impact of physical activity on children and adolescents with metabolic syndrome. Methods: Data surveys. Medline (Pubmed), Cochrane Library, LILACS/VHL. Study selection. Cross-sectional studies (2008-2022) that evaluated the ability of physical training to reduce at least one of the following outcomes: HDL-C; triglycerides; HOMA-IR, Fasting Glucose, systolic blood pressure (SBP); diastolic blood pressure (DBP), Body Mass Index (BMI); 2) Intervention (modality, intervention period, weekly session and duration, weekly frequency, intensity, number of sets and repetitions); in children and adolescents classified as having metabolic syndrome. Data extraction and analysis. Two independent reviewers extracted the data and assessed the quality of the included studies. The differences (physical training group minus control group) in the evaluated results were analyzed using (mean values and standard deviation of pre- and post-intervention, and difference between means). Results. Of the 1,961 articles retrieved, 03 studies were included. This review showed that the practice of physical activity, in general, was associated with a reduction in HDL-C levels (before 44.21 mg/dL (± 9.6), after 42.13 mg/dL (± 7. 76), but was associated with reductions in TG levels (before 113.87 mg/dL after 87.53 mg/dL (26.34). AND HOMA (before 2.54 mg/dL after 2.61 mg /dL) Fasting glucose (before 79.86 mg/dL (±9.22) after 82.43 mg/dL (±8.31). Physical activity is associated with reduced HDL-C levels. Conclusion: seems likely that physical training can play an important role in preventing or delaying metabolic syndrome. We emphasize the need for future intervention studies that investigate the effects of physical activity with greater methodological quality. Keywords: Children; adolescent; physical activity; metabolic syndrome.

12615 Extremely High-dose Insulin Requirement In A Child With Covid-19 Infection

Abstract Disclosure: R. Pratibha: None. T.R. Langner: None. Background: COVID-19 infection has been associated with new diagnosis of diabetes, worsening of hyperglycemia, and increased frequency and severity of diabetic ketoacidosis (DKA) in type 1 diabetes (DM) patients. Stress- related and steroid induced hyperglycemia are also well described during COVID infection with poor glycemic control being linked to more severe SARS-CoV-2 infection outcomes. While insulin needs increase during infection, extremely high insulin requirement is uncommon and not described in the pediatric population. We present here a case of mild COVID infection with transient markedly high insulin requirements. Clinical Case A 16-year-old-African-American- female with history of fairly well controlled type 2 diabetes mellitus on closed loop system insulin pump (Omnipod) with continuous glucose monitor (CGM), was admitted with COVID-19, aspiration pneumonia and hyperglycemia. She had been diagnosed 10 months prior with Hemoglobin A1c (HbA1c) of 11.4% and mild diabetic ketoacidosis (DKA). Diabetes antibodies were negative. Four months prior to admission her HbA1c was 7.8%. Upon this hospitalization she had no hypoxemia or respiratory failure and did not need steroids. Procalcitonin level 0.09 ng/mL was normal. Developmental delay, non-ambulatory and non-verbal status, an underlying mitochondrial neurological disease with G tube and ventilator dependence added to the medical complexity. HbA1c (8.1%) and Fructosamine 316 (n 200-285 mcmol/L) were not indicative of poor control. While her pneumonia resolved promptly, blood sugar (BG) elevation prolonged her hospitalization. She was not in DKA. Despite increasing her basal rate by 50% and an additional 20% higher temporary basal rate via her insulin pump there was little response. She was switched to Insulin drip by the 7th day. Her Insulin rate had increased to 26 units per hour (at 0.64 Units/Kg/hour) by day 8. This high insulin-dose need lasted for around 36 hours, before gradually reducing over a week. She has a history of recurrent pancreatitis. Lipase 335 U/L was elevated initially but started reducing within 2 days and had normalized by day 13. She was transitioned back to her pump although at higher basal rate than the previous home regimen, by 14th day. Conclusion While a constellation of factors such as stress, steroids, underlying poor glycemic control may cause hyperglycemia in COVID-19, these do not explain the high insulin demand in our patient. COVID infection with impaired insulin secretion, mild pancreatitis may have contributed to the brief remarkably high-dose insulin requirement, but it appears to be increased insulin resistance which could possibly explain the transient derangement. To our knowledge this has previously not been described in a pediatric diabetic patient. Presentation: 6/3/2024

6588 Insulin Autoimmune Syndrome Presenting with Severe Insulin Resistance and Recurrent Diabetic Ketoacidosis

Abstract Disclosure: E. Looi: None. R. Rosenberg: None. S. Sugar: None. H. Stone: None. A.W. Michels: None. D. Saxon: None. Background: Insulin autoimmune syndrome (IAS) is a rare cause of severe insulin resistance and is typically associated with intermittent hypoglycemia due to insulin antibodies (IA) with high binding capacity and low insulin affinity. However, consideration should be given for atypical presentation of IAS or co-presentation of IAS with type B insulin resistance syndrome (TBIRS) in the absence of hypoglycemia, as described in this case. Case: A 78-year-old African American female (BMI 21 kg/m2) with poorly controlled type 2 diabetes (A1c 11%) experienced recurrent episodes of diabetic ketoacidosis (DKA) despite adherence to escalating insulin doses (310 units daily, 5 u/kg/day). She was referred to endocrinology and continuous glucose monitoring revealed consistently elevated glucose levels (300-400 mg/dL) without hypoglycemia. She had normal renal function, hepatic function, and lipid panel. During a subsequent hospitalization, she required insulin drip rates of 50-70 u/hr. Insulin resistance workup revealed significantly elevated IA level (8.346, normal ≤ 0.010) measured using a fluid-phase radiobinding assay with high insulin binding capacity (1040 U insulin-binding/L blood) and low insulin binding affinity (1.9x107 M), which supported the diagnosis of IAS. Rheumatologic workup for other autoimmune diseases was negative. Due to recurrent DKA episodes, severe insulin resistance without obvious alternative cause, and lack of hypoglycemic events despite low IA binding affinity, co-morbid TBIRS was considered. As there are no commercially available insulin receptor antibody (IRAb) assays, diagnosis could not be confirmed before her condition worsened, and she was admitted for another episode of DKA within a week of being discharged. Due to clinical deterioration and high suspicion for IAS ± TBIRS, treatment with a combination of immunosuppressive agents was initiated in accordance with an NIH protocol (Klubo-Gwiezdzinska J, et al. 2018). Intravenous immune globulin (0.5g/kg/day) was administered over 2 days which resulted in a brief reprieve and followed by significant relapse. Two doses of rituximab (750 mg/m2) and 2 steroid pulses (dexamethasone 40 mg PO daily for 4 days) were then administered 2 weeks apart. Cyclophosphamide 100 mg daily was also started. Her hyperglycemia and insulin requirements subsequently improved, and she was eventually discharged with good glycemic control on a total daily dose of 40 units of insulin (0.5 u/kg/day), an 87.1% reduction in daily insulin requirement. Conclusion: This case demonstrates that IAS - although classically associated with hypoglycemic episodes - may also present with severe insulin resistance and recurrent DKA without hypoglycemia. Whether characterized by high IA binding capacity and affinity or coexisting with IRAb, a combination of immunosuppressants proved effective in treating both TBIRS and IAS in this instance. Presentation: 6/3/2024

7260 Nuclear Corepressor 1 (NCoR1) plays important role in the regulation of insulin gene transcription in mouse Min6 pancreatic beta cells

Abstract Disclosure: H. Shimizu: None. Y. Horibata: None. I. Amano: None. M.J. Ritter: None. M. Ohyama: None. M. Domae: None. H. Sugimoto: None. A.N. Hollenberg: None. Background: Nuclear Corepressor 1 (NCoR1) is a transcriptional corepressor which has been recognized as an important player in the regulation of hepatic lipogenesis and hematopoiesis in mouse embryo. NCoR1 is also widely expressed in mouse insulin sensitive organs, for instance adipocyte, skeletal muscle, and hepatocytes. Mouse genetic deletion strategies of either NCoR1 or SMRT(NCoR2; an ortholog corepressor of NCoR1) demonstrated that each corepressor effects the insulin sensitivity in the tissues. However, the role of each corepressor in pancreatic beta cell is not still elucidated. Methods: To clarify this, we took the gene-targeting strategy for NCoR1 using CRISPR Cas-9 and made the pancreatic beta Min6 clone which lacks NCoR1 protein (Min6-NCoR1KO; NKO cells). For this study, wild type Min6 cells (WT) and NKO cells were cultured in the Dulbecco's DMEM medium with 10% fetal bovine serum for 4-5 days, and the expression analyses compared between two cell types were performed. Results: Both comprehensive proteomics and following expression analyses compared between WT and NKO cells demonstrated that NKO cells have significantly lower expression level of insulin (INS-1 and INS-2), accompanied with high expression of histone deacetylase 6 (HDAC6). For further analyses, we also made the Min6 clone which lacks SMRT(Min6-SMRTKO; SKO cells). Interestingly, SKO cell had higher insulin and lower HDAC6 levels, accompanied with significant up-regulation of NCoR1. Conclusion: Taken together, these data indicate that NCoR1 has dominant effects in the regulation of both histone deacetylation and insulin gene transcription in Min6 cells. Further investigations for the function of NCoR1 in the insulin gene transcription observed in Min6 cells will be needed. Presentation: 6/2/2024

7943 In Obese C57Bl6 Male Mice, Weight Loss due to Caloric Restriction Reduced Bone Morphology but Improved Components of Systemic Metabolism

Abstract Disclosure: C. Chlebek: None. C. McAndrews: None. S.N. Costa: None. C.J. Rosen: None. Obesity and calorie restriction individually alter systemic cellular metabolism and affect musculoskeletal tissue health. Obesity reduces trabecular and cortical bone quality. Clinically, obese patients are advised to lose weight, despite the negative effects of calorie restriction on bone in nonobese preclinical models. Little is known about bone quality following weight loss in obese preclinical models. We hypothesized that in obese models, caloric restriction would further worsen bone quality. To induce obesity, male C57Bl6 mice (8 weeks old) received 60% high fat diet for 12 weeks (high fat feeding phase). Following obesity induction, the HFD-CR group was acclimated to control low fat diet for 2 wks and then underwent 30% caloric restriction for 8 wks (caloric restriction feeding phase). The HFD group received 60% kcal high fat diet from ages 8 to 30 wks. LFD mice received control low fat 10% kcal diet for the study duration. Mice were euthanized at 30 wks of age. Body weight, body composition, and bone mineral density were recorded at baseline and at the end of each diet. Glucose and insulin tolerance were recorded at the end of the high fat and caloric restriction feeding phases. At euthanasia, cortical and trabecular bone morphology (µCT) were assessed.Adverse metabolic parameters worsened with high fat feeding but improved by caloric restriction. Compared to LFD animals, HFD and HFD-CR mice gained body weight, fat mass, and lean mass during the high fat feeding phase. After the caloric restriction feeding phase, body weight, fat mass, and lean mass were reduced in HFD-CR compared to both HFD and LFD controls (p &amp;lt; 0.0001). After 12 weeks of high fat feeding, glucose and insulin tolerance were reduced in HFD and HFD-CR mice compared to LFD (p &amp;lt; 0.0001). Caloric restriction improved both glucose and insulin tolerance in HFD-CR mice compared to both HFD and LFD animals (p &amp;lt; 0.0001). Caloric restriction improved areal bone mineral density, but at euthanasia, HFD-CR mice had worse bone morphology compared to LFD or HFD animals. Although areal bone mineral density (aBMD) was reduced by the high fat feeding phase, HFD-CR and LFD aBMD was not different at the end of the study (p &amp;lt; 0.0001). At euthanasia, HFD-CR mice had reduced cortical area and cortical thickness (p &amp;lt; 0.05). Marrow area and moment of inertia were not different between diets. Compared to LFD, both HFD and HFD-CR mice had reduced tibial bone volume fraction (p &amp;lt; 0.05). HFD-CR animals had smaller trabecular thickness (p &amp;lt; 0.05) and greater trabecular number (p &amp;lt; 0.01) compared to HFD mice. Despite improvements in components of systemic metabolism, caloric restriction in obese preclinical models reduced bone morphology in both trabecular and cortical compartments. This work will improve our understanding of the musculoskeletal system following caloric restriction in obese models and will aid in nutritional counseling for obese patients. Presentation: 6/1/2024

9179 Type 2 Diabetes Alters Metabolic Fuel Selection During Intermittent Fasting

Abstract Disclosure: M.O. Conn: None. D.M. Marko: None. J.D. Schertzer: None. Type 2 Diabetes Alters Metabolic Fuel Selection During Intermittent Fasting Diabetes is characterized by elevated blood glucose resulting from defective insulin secretion and/or insulin resistance. Intermittent fasting, a popular weight loss strategy involving periodic reduction of caloric intake, can improve glycemia. Fasting shifts metabolism from carbohydrates to free fatty acids and ketones. However, high blood insulin can inhibit lipolysis and alter metabolic substrate selection in prediabetes, resulting in muscle catabolism to maintain energy homeostasis. Clinical studies have observed a significant decrease in muscle mass in subjects with obesity and diabetes. Our research aims to characterize lean mass versus fat loss after intermittent fasting in a mouse model of obesity and type 2 diabetes (T2D) and investigate the role of muscle alanine catabolism. We hypothesized that intermittent fasting would promote less lipolysis and more muscle alanine catabolism, causing more muscle loss in diabetic mice than controls. We compared male db/db mice manifesting obesity, hyperglycemia, and hyperinsulinemia to age-matched db/+ (control) mice. Our lab established a 5:2 repeated fasting protocol of ad-libitum access to food for 5 days a week and 2 days of fasting on non-consecutive days. Blood glucose was monitored weekly in fed and fasted states to assess glycemic control. While intermittent fasting lowered fasted blood glucose in both groups, no significant body weight or metabolic tissue mass changes were observed. Metabolic cage data demonstrated increased reliance on fat-based substrates for energy in control mice that underwent intermittent fasting during feeding and fasting periods. Diabetic mice did not show significant changes in the fasted state, but intermittent fasting led to increased reliance on carbohydrate oxidation during re-feeding periods, indicating impaired metabolic flexibility. After 10 weeks, the mice were sacrificed, and metabolic tissue histology (adipose, liver, skeletal muscle) will be performed. We will also analyze serum markers (alanine, fatty acids, glycerol, glucose, insulin) and the activity of the metabolic enzyme alanine transaminase (ALT) in the muscle and liver. This experiment will improve our understanding of how lipolysis and protein breakdown in muscle regulate lean mass versus fat mass loss in obesity and T2D, leading to more effective tailoring of fasting to specific populations. Presentation: 6/3/2024

5104 Ectopic Insulinoma- a Rare Presentation of a Rare Tumor

Abstract Disclosure: O. Lavrynenko: None. A. DeMarsilis: None. C. Jiang: None. R. Middelbeek: None. H. Rosen: None. M.E. Patti: None. Background. Insulinoma is a rare, functioning neuroendocrine tumor (NET) typically localized within the pancreas, that secretes insulin, resulting in hypoglycemia. Ectopic insulinoma is even more rare than pancreatic insulinoma and is more difficult to diagnose. Case report. This 31-year-old previously healthy woman, who had an uncomplicated pregnancy and a healthy baby in October 2021, presented with intermittent hypoglycemia for more than 8 months. She denied any prior use of insulin or antidiabetic medications and was not currently taking any medications at all. There is no history of bariatric or other GI surgery. While nursing her baby in early 2022, she was noted to have a capillary blood glucose (BG) between 20-30 mg/dl, and reported both adrenergic and neuroglycopenic symptoms of hypoglycemia; these usually occurred in the morning or before lunch, especially if lunch was delayed. She wore a Libre CGM which revealed episodic hypoglycemia, which correlated with her timeline of symptoms. She reported weight gain of 8 lbs during this period. Laboratory data obtained after a 10-12 hour fast revealed hypoglycemia (venous glucose 39 mg/dL) with inappropriately high plasma insulin (42.3 mIU/ml), C- peptide (3.78 ng/ml), and proinsulin (99 pmol/L). Beta-hydroxybutyrate was 0.05 mmol/L (reference &amp;lt;0.28) and insulin autoantibody and sulfonylurea screen were negative. Various imaging modalities for localization revealed a solitary omental mass outside the pancreas consistent with extra-pancreatic insulinoma. No pancreatic lesion or other findings were observed with MRCP, CT C/A/P or endoscopic ultrasound. The patient underwent CT-guided biopsy of the omental mass, which confirmed a well-differentiated NET, consistent with insulinoma. Due to persistent hypoglycemia, she was started on corn starch and diazoxide. She subsequently underwent laparoscopic resection of the mass. Postoperative pathology revealed a well-differentiated NET staining positive for insulin, consistent with an extra-pancreatic insulinoma. Following surgical resection of the insulinoma, her hypoglycemia resolved even off corn starch and diazoxide. Conclusion. Ectopic insulinoma is a rare insulin-secreting NET. Only 28 ectopic insulinomas have been described in the literature to date1. We describe a patient with symptomatic hypoglycemia who was found to have an omental neuroendocrine tumor; hypoglycemia completely resolved after laparoscopic enucleation of the ectopic insulinoma. 1Fernando Guerrero-Pérez, Nuria Vialarrasa, Lidia V. Huanuco et. al. Ectopic Insulinoma: a systemic review: Reviews in Endocrine and Metabolic Disorders, 2023 Presentation: 6/1/2024

7378 Glargine Induced Neuroglycopenia in Patients with End-Stage Renal Disease: Importance of Insulin Regimen Optimization in Haemodialysis Patients

Abstract Disclosure: M. Shrivastava: None. L. Kaur: None. B. Armendariz: None. R. Kaur: None. A. Shetty: None. In patients with end stage renal disease (ESRD), hypoglycemia accounts for up to 3.6% of all the admissions with mortality rates of up to 30%. A combination of impaired insulin clearance, changes in glucose metabolism and dialysis process makes the patients with end stage renal disease vulnerable to neuroglycopenia.Case description:53 year old female with past medical history of insulin dependent type 2 diabetes mellitus, ESRD secondary to diabetes, on hemodialysis(HD) thrice weekly since two years, presented to the emergency with altered mental status, respiratory distress, tachycardia. Lab work revealed blood glucose(BG) of 23 mg/dl, HbA1c of 8.4%, eGFR of 6, and arterial blood gas showed hypercapnic respiratory acidosis. Patient received dextrose, with no improvement of symptoms. Eventually she developed acute hypercapnic respiratory failure requiring endotracheal intubation with mechanical ventilation, and was transferred to the ICU. As per family, a night prior to presentation, last recorded BG after dinner was 253 mg/dl, she took her night time glargine, which was recently increased by her primary care for poorly controlled HbA1c levels. Brain MRI and long term EEG monitoring findings were consistent with underlying extensive brain injury secondary to prolonged hypoglycemia. Unfortunately, the patient's condition did not improve despite HD and BG correction, eventually she underwent compassionate extubation. Case Discussion:The insulin requirements in ESRD patients are reduced by approximately 50%, regardless of residual insulin secretion. Malnutrition and acidosis reduce hepatic glycogen stores and availability of gluconeogenic precursor, expected compensatory renal gluconeogenesis is compromised by decreased renal function causing hypoglycemia, which is further worsened by inappropriately high plasma insulin levels caused by reduced renal insulin breakdown. Diabetes mellitus patients with ESRD are frequently managed with basal-bolus insulin regimen, and HD up to thrice weekly, leaving them without HD for up to 3 days especially over the weekend. This can result in accumulation of insulin metabolites causing delayed insulin clearance as seen in our patient. In such cases even long acting insulin, such as glargine, can have compounding effects, which could possibly cause fatal complications such as neuroglycopenia. In such patients continuous glucose monitor use with tapering dose glargine regimen may help eliminate this compounding effect. Conclusion: Neuroglycopenia is a rare manifestation of diabetes mellitus with ESRD. Compromised renal gluconeogenesis and impaired insulin clearance can cause inappropriately high plasma levels of insulin. In such patients continuous glucose monitoring along with tapering dose of long acting insulin should be utilized for proper glycemic control to limit compounded effect of insulin metabolite accumulation. Presentation: 6/3/2024

5175 A Rare Case of Type B Insulin Resistance Syndrome

Abstract Disclosure: S. Fatima: None. A. Champion: None. S. Ward: None. Q. Aziz: None. K.E. Izuora: None. Introduction: Severe insulin resistance may be defined as a severely diminished response to insulin’s biological effects and is characterized by substantial hyperinsulinemia and impaired glucose response to endogenous and exogenous insulin. We hereby present a rare case of Type B Insulin Resistance Syndrome (TBIRS). Case:40-years old female with history of systemic lupus erythematosus (SLE), diabetes mellitus was admitted with multiple rheumatologic complaints, including arthralgias, oral ulcers, skin rash, and hair loss secondary to SLE flare. Endocrinology was consulted for diabetes management. Her HbA1c had increased from 7.3% to 11.6% in 3 months despite taking Glargine 45 units daily, Lispro 15 units pre-meals and metformin. She noticed 80 lbs weight loss for past 6 months. Her BMI was 26 and exam showed acanthosis of neck, armpits, groin, hair loss on scalp, multiple genital ulcers, and facial rash. She was noted to have refractory hyperglycemia despite high insulin doses. By 14th day of hospitalization, she was on 287 units of insulin (3.4units/kg) daily. We suspected TBIRS in the setting of SLE. Metformin and pioglitazone were started. Further testing showed insulin level 152mIU/ml (2.6-14.9mIU/ml), C-peptide 1.7 ng/ml (1.1-4.4 ng/ml), islet-cell antibody negative, GAD-65 antibody &amp;lt;5 u/ml, insulin antibody 6.5 uU/ml, IGF-1 14 (79-259 ng/ml), adiponectin 13.3 (2.4-17.9 ug/ml), testosterone 7 (8-60 ng/dl), free testosterone &amp;lt;0.2 (0-4.2 pg/ml), total cholesterol 200 mg/dl (&amp;lt;200 mg/dl), triglycerides 85 mg/dl (&amp;lt;150 mg/dl), LDL 154 mg/dl (&amp;lt;100 mg/dl), HDL 29 mg/dl (&amp;gt;60 mg/dl). She was transferred to National Institute of Health for further care. She was confirmed to have TBIRS by insulin receptor antibody testing, started on regular insulin U500 initially, and then switched to IV insulin drip requiring up to 1700 units of insulin per hour. She received methylprednisolone, cyclophosphamide (2 doses), rituximab (2 doses), hydroxychloroquine and IV immunoglobulin. Her stay was complicated by hemophagocytic lymphohistiocytosis. She was discharged on U-500 Regular insulin, 1000 units with breakfast and 500 units with lunch, Prednisone 60 mg daily and Hydroxychloroquine. Two months later she was found unresponsive at home secondary to hypoglycemic seizures. She required dextrose drip and was discharged on Glargine 16 units and Lispro 6 units with meals. Conclusion: TBIRS is caused by a highly specific polyclonal autoantibody against the cell surface insulin receptor that decreases the cellular insulin response and causes refractory hyperglycemia. About 100 cases have been reported in literature. 60% of the cases are associated with SLE. The goal of therapy is to reverse the hypercatabolic state with high doses of insulin and to eliminate the autoantibodies with immunosuppressive therapy. The most common cause of mortality is hypoglycemia. Presentation: 6/3/2024