bluuebunny/crossref_metadata_2025 huggingface dataset:
1123-P: Analysis of Readmissions for Diabetic Ketoacidosis in Patients with Hidradenitis Suppurativa: A Nationwide Analysis
Authors: EDIGIN EHIZOGIE , SHAKA HAFEEZ , ESEATON PRECIOUS O. , ALMANI MUHAMMAD USMAN , KICHLOO ASIM , OJEMOLON PIUS E. , JAKHAR DEEPAK
Published: June 2021

Hidradenitis suppurativa (HS) is known to increase the risk of diabetes mellitus. This study aims to compare rates and outcomes of 30-day readmissions following admissions for type 1 diabetic ketoacidosis (T1DKA) in patients with and without co-existing Hidradenitis Suppurative (HS) in the United States.

We analyzed the 2018 National Readmission Database. We included index hospitalizations for all patients (aged≥18 years) with a principal diagnosis of T1DKA using ICD-10 codes. We further sub-stratified this group into those with and with a secondary diagnosis of HS. Chi-square tests and regression analysis were used to compare rates and outcomes of 30-day readmissions between both groups. We excluded elective and traumatic readmissions.

A total of 94,461 index hospitalizations for T1DKA, that were discharged alive, were included in the analysis. 109 (0.2%) of these, had co-existing HS. A total of 15,614 (16.5%) readmissions occurred within 30 days. Readmission rates were similar between HS and non-HS group (21.8% vs. 16.5%, p=0.328). HS group had a similar mean hospital length of stay (3.0 days vs. 2.9 days, p=0.645) and mean total hospital costs ($6,878 vs. $7,236, p=0.691) compared to the non-HS group. Readmissions for T1DKA in HS patients were associated with a total of 331 hospital days and $747,976 in hospital costs. T1DKA without coma was the most common reason for readmission in both groups.

HS patients admitted for T1DKA have a greater, but statistically non-significant rate of 30-day readmission, and similar readmission outcomes compared to non-HS patients admitted for TIDKA.

Disclosure

E. Edigin: None. H. Shaka: None. P. O. Eseaton: None. M. Almani: None. A. Kichloo: None. P. E. Ojemolon: None. D. Jakhar: None.
1125-P: Do Non-HLA Genes Contribute to Age of Type 1 Diabetes Onset in Monozygotic Twins?
Authors: TRIOLO TAYLOR M. , DONG FRAN , BRONCUCIA HALI C. , ONENGUT-GUMUSCU SUNA , STECK ANDREA , RICH STEPHEN S.
Published: June 2021

Development of islet autoimmunity (IA) and type 1 diabetes (T1D) are associated with high-risk HLA class II loci as well as non-HLA genes. Monozygotic (MZ) twins have a high rate of concordance to T1D progression after the first twin develops T1D, especially for those diagnosed at a young age. We analyzed 52 T1D-associated non-HLA SNPs from ImmunoChip data in 159 MZ twins from the Twin Family Study: 79 twin probands with T1D and their 80 unaffected cotwins/triplets (including one set of triplets). Subjects are enrolled into the Twin Study when the proband is diagnosed with T1D and cotwins are followed longitudinally for the development of IA and/or T1D. In the cotwins, we analyzed the association between each of the non-HLA SNPs and IA after adjusting for HLA DR3/4*0302. In the twin probands with T1D, we used a linear regression model to evaluate the association of non-HLA SNPs with diabetes age at onset after adjusting for HLA DR3/4*0302. Median (IQR) age of diagnosis of the twin probands was 9.9 (5.4-13.9) years and age of last visit for the cotwins was 17.5 (11.2-26.7) years. Of the 80 cotwins, 41 (51.3%) developed IA and 15 (18.8%) were diagnosed with T1D. After adjusting for HLA DR3/4*0302, SNPs in CTLA4 (rs3087243), IL2 (rs4505848), IKZF1 (rs62447205), and INS (rs7111341) were found to be associated with the development of IA in cotwin subjects (all p<0.04). After adjusting for HLA DR3/4*0302, SNPs in CTSH (rs3825932) and TYK2 (rs34536443) were found to be associated with younger age of diabetes onset in the twin probands (p<0.05). In this cohort of MZ twins, non-HLA SNPs in CTSH and TYK2, which function both in the immune system and in beta cells, were associated with younger age of onset in the twin probands. Further studies are needed to evaluate the specific role of these genes for immunity and T1D onset.

Disclosure

T. M. Triolo: None. F. Dong: None. H. C. Broncucia: None. S. Onengut-gumuscu: None. A. Steck: None. S. S. Rich: None.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (K12DK094712)
1127-P: Expression-Based Genome-Wide Association Study Links Osteopontin and Interleukin-1 Receptor Antagonist with Type 1 Diabetes
Authors: JIA XIAOFAN , TODA KYOKO , HE LING , MIAO DONGMEI , YAMADA SATORU , YU LIPING , KODAMA KEIICHI
Published: June 2021

Type 1 diabetes (T1D) is caused by autoimmune destruction of insulin-producing β-cells in the pancreatic islets. Islet autoantibodies (IAbs) are indicators of islet autoimmunity. However, IAbs do not fully meet the need for the prediction of future hyperglycemia and the rate of disease progression. We assumed that functional proteins associated with autoimmune cellular process are great sources for biomarkers. In an attempt to identify additional biomarkers, we performed an expression-based genome-wide association study (eGWAS) using microarray data from 169 arrays of the pancreatic islets of T1D rodents. We ranked all 16,099 protein-coding genes by the likelihood of finding repeated differential expression in the pancreatic islets. Our top 20 secreted proteins were screened using the serum samples from newly diagnosed children with diabetes. First, we screened 20 selected candidates with 170 sera including 100 T1D, and 50 type 2 diabetes (T2D) and 20 age matched healthy children. With 7 proteins showing significance, we further did validation study using the second set of 400 samples from newly diagnosed children with diabetes and age matched controls including 200 T1D, 100 T2D, and 100 age-matched controls. We identified 2 serum proteins were significantly changed in T1D vs. both control and T2D and 5 serum proteins were significantly changed in both T1D and T2D vs. control. Serum Osteopontin (OPN) levels were uniquely higher in T1D (p< 0.0001) with no difference between T2D and healthy control subjects. Serum Interleukin 1 receptor antagonist (IL-1RA) levels were lower in T1D compared with both T2D (p<0.001) and healthy subjects (p< 0.0001). Our results suggest that OPN and IL1RA could be the useful biomarkers of T1D in children.

Disclosure

X. Jia: None. K. Toda: None. L. He: None. D. Miao: None. S. Yamada: None. L. Yu: None. K. Kodama: None.

Funding

JDRF (2-SRA-2019-695-S-B)
114-LB: Metformin-Associated Lactic Acidosis Risk Assessment in Veterans on Continuous Oxygen Therapy
Authors: LUTZ-MCCAIN STACEY J. , DESANZO BETH E. , HERK BRANDON , MCLINDEN MEGHAN , DINARDO MONICA M. , CODARIO RONALD
Published: June 2021

Metformin is the most prescribed oral medication for type 2 diabetes in the US due to its low cost, efficacy in reducing insulin resistance, and overall safety profile. However, literature shows that metformin can cause a rare but serious side effect of lactic acidosis (LA) with an incidence of 0.03-0.06 per 1000 patients. Persons requiring continuous oxygen therapy (COT) may be at risk for LA associated with hypoxia and decreased tissue perfusion, but the risk of metformin associated lactic acidosis (MALA) in persons requiring COT is unclear. Due to lack of evidence, some clinicians may empirically discontinue metformin in patients on COT, compromising glycemic stability. The objective of this drug utilization evaluation was to determine the frequency of metformin use and incidence of MALA in patients receiving COT.

A retrospective review was conducted at a large regional Veterans Affairs Medical Center for patients with active prescriptions of metformin and supplemental oxygen therapy from 4/2017-4/2020. Of 578 unique patients identified, manual medical-record review was conducted for 6 patients who had serum lactate levels >4 mmol/L while using concomitant metformin and COT. All were white males with mean: age of 71, pH of 7.35, and eGFR of 56. No cases of LA or DKA were identified. In all cases, elevated lactate levels were attributed to advanced medical conditions including: COPD, sepsis, CHF, CKD, and liver disease. None had serum metformin levels drawn.

In conclusion, the association of elevated serum lactate among persons using concomitant metformin and COT was low and occurred in persons with advanced medical conditions. It could not be determined if metformin use was a contributing factor without metformin levels. These findings confirm the importance of clinical judgement when prescribing and continuing metformin for persons with advanced underlying medical conditions. Further study with serum metformin levels may help to better characterize the risk of MALA for persons on COT.

Disclosure

S. J. Lutz-mccain: None. B. E. Desanzo: None. B. Herk: None. M. Mclinden: None. M. M. Dinardo: None. R. Codario: None.
1140-P: Immune Dysregulation as a Consequence of Aberrant Glycemic Control in Diabetes Mellitus
Authors: SABAPATHY VIKRAM , DOGAN MURAT , VENKATADRI RAJKUMAR , ARBAB RAJIA , MA JENNIE Z. , BASU ANANDA , BASU RITA , SHARMA RAHUL
Published: June 2021

People with diabetes mellitus are more vulnerable to viral infections including influenza and the ongoing COVID-19 pandemic. Fatal pneumonia and cytokine storm is a contributor to the mortality. We hypothesized that aberrant glycemic control induces an immune dysregulation, which compromises the anti-viral immunity and promotes inflammation by altering the balance of the protective T-regulatory cells (Tregs) and IL-17 responses. Indeed, comparison of the peripheral blood lymphocytes in a limited cohort of healthy controls (HC; n=4) and people with diabetes (n=9) showed profound immune dysregulation. As compared to HC (66±21 x10^3/ml), the number of circulating Tregs were significantly (p<0.0001) reduced in diabetes group (15±2 x10^3/ml). Compared to HC, the proportion of IL-17 producing CD4 and CD8 T-cells was remarkably increased in the diabetes group at baseline as well as upon ex-vivo stimulation. A comparison of the ratio of IFNγ to IL-17 producing CD8 T-cells showed a significant bias towards reduced IFNγ and enhanced IL-17 production in the diabetes group (4.7±1.7) as compared to the HC (35±4). Similarly, comparison of the ratio of Tregs and Th1 to Th17 cells was also significantly biased towards reduced Treg and Th1 cells, and an exacerbated Th17 response in diabetes group as compared to the HC. Meta-analysis confirmed a significant positive correlation between HbA1c levels and the exacerbated IL-17 to IFNg ratios in CD4 (R2=0.7, p=0.0008) as well as CD8 (R2=0.6, p=0.002) cells.

In summary, altered glycemic control, as indicated by higher HbA1c levels, significantly correlates with compromised IFNg production in the CD8 and Th1 cells, which is important for anti-viral immunity, as well as a marked proinflammatory shift shown as reduced Tregs levels and enhanced IL-17 production by both CD4 and CD8 cells. This immune-dysregulation in diabetes may thus contribute to a greater susceptibility to viral infections and infection-induced pathology.

Disclosure

V. Sabapathy: Stock/Shareholder; Self; 10x Genomics, Apple, AstraZeneca, Bayer U. S., Gilead Sciences, Inc. M. Dogan: None. R. Venkatadri: None. R. Arbab: None. J. Z. Ma: None. A. Basu: None. R. Basu: None. R. Sharma: Other Relationship; Self; SlateBio Inc.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (R01DK104963); University of Virginia
1144-P: Chemical Assessment of Populations of Human Pancreatic Islets Isolated for Transplantation
Authors: RUBAKHIN STANISLAV , ROMANOVA ELENA V. , SWEEDLER JONATHAN V.
Published: June 2021

Clinical transplantation of human cadaveric islets is an important therapy for the treatment of T1D. Such transplantation has demonstrated safety and efficacy in academic and clinical trials. Quality control during all stages of islet isolation, handling, and transplantation is critical for success of the therapy. A variety of tests are used to assess cellular integrity, islet population purity, and potency. Unfortunately, most of applied tests are not evaluating individual pancreatic islet chemical compositions which are indicative of overall islets functional and health state. Here we describe the results of mass spectrometric (MS) assessment of populations of individual pancreatic islets received from seven donors including four T2D cases. Random sampling and MS analysis of 232 islet-like structures detected 150 islets (based on size, morphology, and visual inspection). Our findings correlate (R2=0.9) with data on sample purity for different batches provided by the ADI IsletCore. The classic pancreatic islet hormones are observed in the majority of islets. Peptide profiles are mostly dominated by insulin, although we observe a greater variability of insulin peaks than somatostatin- and glucagon-related signals by mass spectrometry. No significant differences in our results are observed between healthy and T2D-affected islets. Fast mass-spectrometry-based assessment allowed selection of representative individual islets for liquid chromatography-MS (LC-MS), which provides an in-depth chemical coverage. Using LC-MS, a number of histone-related peptides are detected significantly expanding analyte coverage. To increase the throughput of direct MS analysis of islets, we use our optically guided mass spectrometry approach to automate the localization and analysis of larger islet populations. Using this technology and MS detection, hundreds of islets can be profiled for presence of a variety of metabolites, lipids, and peptides during a several-hour timespan.

Disclosure

S. Rubakhin: None. E. V. Romanova: None. J. V. Sweedler: None.

Funding

American Diabetes Association/Pathway to Stop Diabetes (1-18-VSN-19 to J.V.S.)
1145-P: Association of Muscle Mass Loss and Diabetes Development in Liver Allograft Recipients
Authors: LEE SEJEONG , KIM HAE KYUNG , KIM YOUNG-EUN , LEE MINYOUNG , JOO DONG JIN , KIM MYOUNG SOO , KANG EUN SEOK
Published: June 2021

There has been increased recognition of the importance of post transplantation diabetes mellitus (PTDM), which is one of the most frequent complications after liver transplantation. Patients with end-stage liver diseases requiring transplantation are prone to be sarcopenic but the association between sarcopenia and PTDM remains inconclusive. We investigated the effect of postoperative muscle mass loss on the risk of PTDM development by measuring muscle area using computed tomography (CT) in Liver Allograft Recipients before and after transplantation. A total of five hundred patients who received liver transplantation between 2005 and 2020 were included from tertiary care hospital. Skeletal muscle area (cm2) at the level of vertebra L3-L5 was measured using CT scans performed before and 1 year after the transplantation, and the area was normalized to height squared (m2). Cox proportional hazard model was used to investigate the associations between the change in the muscle area after the transplantation (Δmuscle area) and the incidence of PTDM. Patients were divided into two groups (with muscle loss and without muscle loss). During the study follow-up period (median 4.9 years), PTDM occurred in 165 patients (33%). Muscle depletion was significantly associated with the increased risk of incident PTDM after adjustment for age, BMI, model for end-stage liver disease score and fasting blood glucose after liver transplantation (hazard ratio, 1.47; 95% confidence interval, 1.23-1.76; p<0.001). Δmuscle area predicted PTDM development with a receiver operating characteristic area under the curve of 0.633 (95% confidence interval, 0.573-0.694). The cumulative incidence of PTDM was significantly higher in the patients with muscle loss than in the patients without muscle loss (P=0.026). The muscle depletion after liver transplantation is associated with the increased risk of PTDM development.

Disclosure

S. Lee: None. H. Kim: None. Y. Kim: None. M. Lee: None. D. Joo: None. M. Kim: None. E. Kang: None.
1150-P: A Hyperhomocysteinemia-Inducing Diet Alters Gut Microbiome and Glucose Homeostasis
Authors: CHENG CHAK KWONG , WANG CHENGUANG , HUANG YU
Published: June 2021

Hyperhomocysteinemia (HHcy) is a risk factor for higher mortality in type 2 diabetic patients. A high methionine low folate (HMLF) diet chronically induces HHcy by causing homocysteine (Hcy) accumulation in systemic circulation. A higher systemic Hcy level is clinically associated with the incidence of diabetes mellitus. However, whether HHcy negatively impacts on glucose metabolism and insulin sensitivity remains inconclusive and contradictory. Meanwhile, very few studies have focused on the direct impact of HMLF diet on glucose homeostasis, and that on the gut flora. To understand the impact of HMLF diet, C57BL/6 mice were fed a HMLF diet for 8 consecutive weeks. HMLF diet feeding successfully induced HHcy, caused progressive body weight loss, and slightly impaired glucose homeostasis, as revealed by slight glucose intolerance and insulin resistance, in C57BL/6 mice. Of noted, HMLF diet feeding altered the gut microbiome profile that the relative abundance of porphyromonadaceae family of bacteria was enriched in diet-induced HHcy mice. Interestingly, a previous study correlated the higher frequency of porphyromonadaceae with the development of GLP-1 resistance, implying that HMLF diet might prompt the development of GLP-1 resistance. GLP-1 resistance results in the impairment on glucose-induced insulin secretion. These results provide novel insights into the roles of impaired glucose homeostasis and gut microbiome in the pathogenesis of HHcy-related complications. In short, an improper dietary pattern might impair glucose homeostasis by altering the gut microbiome profile.

Disclosure

C. Cheng: None. C. Wang: None. Y. Huang: None.

Funding

Chinese University of Hong Kong (4930709); Hong Kong Research Grants Council Senior Research Fellow Scheme 2020/21 (SRFS2021-4S04)
1155-P: Neurocircuits Controlling Adaptive Thermogenesis Rely on Skin Detection of External Temperatures through Calcitonin Gene-Related Peptide Expressing Spinal Neurons
Authors: RIERA CELINE
Published: June 2021

Heat-sensory neurons arising from the dorsal root ganglia (DRG) play a pivotal role in the detection of cutaneous temperature and transmission of external signals to the brain, ensuring the maintenance of thermoregulation. However, whether these thermoreceptor neurons contribute to adaptive thermogenesis has remained elusive. We show that genetic ablation of heat sensing Calcitonin Gene-Related Peptide α (CGRPα) neurons promotes resistance to weight gain upon high fat diet (HFD) feeding and increases energy expenditure in mice. Mechanistically, we find that loss of CGRPα-expressing sensory neurons is associated with reduced lipid deposition in adipose tissue, enhanced expression of fatty-acid oxidation genes, higher ex-vivo lipolysis in primary white adipocytes and enhanced mitochondrial respiration from iBAT. Remarkably, mice lacking CGRPα sensory neurons manifest increased tail cutaneous vasoconstriction at room temperature. This exacerbated cold perception was not associated with reduced core temperature, suggesting that heat production and heat conservation mechanisms are engaged. Specific denervation of CGRPα neurons in intrascapular BAT did not contribute to the increased metabolic rate observed upon global sensory denervation. Taken together, these findings highlight an important role for cutaneous thermoreceptors in regulating energy metabolism, by triggering counter-regulatory responses involving energy dissipation processes including lipid fuel utilization and cutaneous vasodilation.

Disclosure

C. Riera: None.

Funding

American Diabetes Association/Pathway to Stop Diabetes (1-15-INI-12 to C.R.)
1171-P: HORMAD1, a Novel Hypoxia-Inducible Factor-1 Target, Is Upregulated in Maternal Overnutrition-Induced Nonalcoholic Steatohepatitis (NASH)/Hepatocellular Carcinoma
Authors: TAKIYAMA TAKAO , BESSHO RYOICHI , KITSUNAI HIROYA , TAKEDA YASUTAKA , SAKAGAMI HIDEMITSU , SERA TOSHIHIRO , NAKAMURA MASANORI , HORIKE SHIN-ICHI , NISHIKAWA YUJI , TAKIYAMA YUMI
Published: June 2021

We investigated whether overnutrition during pregnancy were associated with the changes in gene expressions, oxygen metabolism, and vascular and hepatic parenchymal remodeling in fetal livers at mid gestational days E14.5 of dams fed a control diet (CD group) or a high-fat diet (HFD group) during pregnancy. Synchrotron-based phase-contrast micro-CT demonstrated embryos of HFD group showed hepatomegaly accompanied with the same size umbilical vein and less portal branching, which might result in liver hypoxia. Correspondingly, fetal livers of HFD group increased the expression of HIF-1alpha. To identify genes and pathways targeted by maternal overnutrition in fetal livers, we assayed mRNA levels with microarray. We identified 430 differentially expressed genes (DEGs) including 146 upregulated- and 284 downregulated genes in fetal livers of HFD group compared with those of CD group. The up-regulated DEGs were significantly enriched in DNA alkylation, bile secretion, and the down-regulated DEGs mainly enriched in neuronal system, cell maturation. Among upregulated DEGs, a cancer/testis antigen HORMAD1 was induced by hypoxia up to 30-fold compared with that in normoxia in primary mouse hepatocytes (PMH), and the genetic inhibition of HIF-1alpha by siRNAs abolished the stimulatory effect of hypoxia on Hormad1 expression. In addition, we found three putative hypoxia response elements within the mouse Hormad1gene. Interestingly, the tumor suppressor WW domain-containing oxidoreductase (WWOX), which inhibits the activity of HIF-1alpha, were remarkably decreased in hypoxia in PMH. Finally, HORMAD1 protein was upregulated in fetal livers and NASH-based HCC in offspring of HFD group at 15 weeks old. Our results suggest that WWOX-HIF-1alpha-HORMAD1 pathway might be involved in the development of NAFLD in offspring of obese and/or diabetic pregnant woman, and be an important therapeutic target of NASH/HCC.

Disclosure

T. Takiyama: None. Y. Takiyama: Other Relationship; Self; Gilead Sciences, Inc., Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Mochida Pharmaceutical Co., Ltd., Roche Diabetes Care, Taisho Pharmaceutical Co., Ltd. R. Bessho: None. H. Kitsunai: None. Y. Takeda: None. H. Sakagami: None. T. Sera: None. M. Nakamura: None. S. Horike: None. Y. Nishikawa: None.
1173-P: Sex Differences in NASH Pathways Informed by Multiomics
Authors: BLENCOWE MONTGOMERY , NORHEIM FRODE , SALEEM ZARA , HSU NEIL S. , HUI SIMON , PAN CALVIN , KRISHNAN KARTHICKEYAN CHELLA , EDILLOR CHANTLE , YANG XIA , LUSIS ALDONS
Published: June 2021

Nonalcoholic fatty liver disease (NAFLD) has presented itself as a significant health burden, with increasing prevalence globally and evidence of a sexually dimorphic disease course. Particularly, it is of critical importance to understand the latter stage of disease, nonalcoholic steatohepatitis (NASH) with fibrosis, which is more prevalent and severe in males, in order to provide better prevention, treatment, and biomarker options to reduce the health burden. Our mechanistic understanding of NASH progression is far from elucidated, and thus, we present a multi-omics pathway and network analysis utilizing genomic, transcriptomic, and lipidomic data from the Hybrid Mouse Diversity Panel (HMDP) to uncover key biological processes and key driver genes causal to liver fibrosis and to dissect sex differences. Analyzing these multi-omics datasets by sex, we present mechanistic differences important to fibrosis development between males and females. We find that males present with greater enrichment of immune processes as well as abnormalities in protein and lipid metabolism, whereas females present with significant abnormalities linked with carbohydrate metabolism processes, suggesting differential causal mechanisms of fibrosis progression between sexes. Comparing males and females, we also find consistent processes such as extracellular matrix development, clearly vital for fibrosis to develop. Using gene regulatory network analysis of the liver tissue, we further identified key network genes driving the sex-specific processes as well as those consistent between sexes that are important for liver fibrosis. Our multi-omics integrative studies offer comprehensive understanding of NASH in a sex-specific manner.

Disclosure

M. Blencowe: None. A. Lusis: None. F. Norheim: None. Z. Saleem: None. N. S. Hsu: None. S. Hui: None. C. Pan: None. K. Chella krishnan: None. C. Edillor: None. X. Yang: None.

Funding

National Institutes of Health (R01DK117850)
1177-P: The Reduction in Hepatic Steatosis after Cushing’s Syndrome Treatment Is a Marker of Improving Glycemia
Authors: PIERCE ANNE , SATER ZAHRAA A. , CYPESS AARON M.
Published: June 2021

Cushing Syndrome (CS) is characterized by cortisol excess that leads to impaired glucose tolerance and obesity. CT imaging shows 20% of CS patients have nonalcoholic steatohepatitis (NASH). While the gold standard diagnostic test for NASH is liver biopsy, it has too much risk for CS patients. This study evaluated the ability of noninvasive, magnetic resonance spectroscopy (MRS) to measure liver fat percentage in CS patients and followed temporal changes in metabolic parameters before and after successful treatment. The primary outcome was protein density fat fraction (PDFF) by MRS at 3 timepoints: baseline, 6 months, and 12 months after treatment, which consisted of surgery as indicated based on ACTH source. The diagnosis was confirmed if there was histology consistent with corticotrope adenoma, adrenal tumor, or an ectopic source. We prospectively studied 41 consecutive patients: 85% female; 44±1.8 y; 32.6±1.5 kg/m²; urine cortisol excretion 2242.7±1806.3 [nl 3.5-45.0 mcg/24h]). Each underwent MRS at 3T where NASH was defined as >5% PDFF. A1c and BMI were measured. Changes over time were evaluated using Wilcoxon signed-rank test, and correlation among variables was done with Spearman’s rank test. At baseline, mean PDFF was 10.4±1.7 and correlated positively with BMI (r=0.57, P<0.001). NASH was present in 32% of patients. PDFF reductions were similar after 6 and 12 months of treatment (-52%, P=0.001 and -50%, P=0.02); rates of NASH declined to 13% and 11%; BMI decreased (-9%; P=0.002 and -12%, P<0.001). A1c was lower at 12 months (6.2±1.1 to 5.6±0.5, P<0.001). The reduction in liver fat correlated with changes in visceral fat mass (r=0.70, P<0.001).

In summary, MRS-PDFF was effective at diagnosing NASH in CS. Physiologically, definitive treatment of CS reduced liver fat by 6 months after normalization of cortisol and also preceded the improvement in A1c. These results suggest that liver insulin resistance due to fat accumulation has an important role in diabetes pathophysiology in CS.

Disclosure

A. Pierce: None. Z. A. Sater: None. A. M. Cypess: None.
1189-P: Ankyrin-B Modulates the Integrity and Bioenergetic Capacity of Skeletal Muscle Fibers
Authors: VOOS KAYLEIGH , TZENG JOYCE , LORENZO DAMARIS
Published: June 2021

Ankyrin-B (AnkB) is a cytoskeletal protein that positions and stabilizes specialized membrane-associated protein complexes. AnkB also associates with organelles and facilitates their dynamics across cell types. AnkB variants have been linked to higher risk for obesity and type 2 diabetes (T2D) in humans and mice. In skeletal muscle (SKM), AnkB localizes to costameres and acts as a scaffold to β-dystroglycan/dystrophin complexes. This protein complex has been demonstrated to be essential for SKM integrity and exercise injury protection. However, besides this structural role, our findings suggest that AnkB associates with mitochondria in SKM and likely plays important roles in SKM bioenergetics. We found that non-obese young mice lacking AnkB solely in SKM (SKM-AnkB KO) develop early signs of myofibrillar disorganization and fibrosis and display reduced physical activity without changes in body weight, fasting glucose levels, or peripheral insulin response. In contrast, SKM-AnkB KO mice are more susceptible to the metabolic effects of a HFD, manifested as lower insulin sensitivity and further reductions in physical activity. Our findings suggest that loss of myofibril organization synergizes with changes in mitochondrial function to worsen SKM bioenergetics and insulin action. These physiological alterations are in agreement with our RNA-seq and proteomics studies, which implicate AnkB in the regulation of SKM oxidative capacity, protein translation, and cellular responses to stress and nutrient availability. We will discuss our ongoing efforts to uncover the mechanistic basis of these metabolic impairments cause by AnkB deficits.

Disclosure

K. Voos: None. J. Tzeng: None. D. Lorenzo: None.

Funding

American Diabetes Association (1-19-JDF-081 to D.L.)
119-OR: Ankyrin-B Modulates Lipid Metabolism in Brown Adipocytes
Authors: AGUILLARD ASHLEY , TZENG JOYCE , LORENZO DAMARIS
Published: June 2021

Human variants in the membrane adaptor ankyrin-B (AnkB) present at frequencies from 0.05 to 7% across different ethnicities have been linked to obesity and type 2 diabetes (T2D). We reported that knock-in mice bearing T2D-linked human AnkB variants develop age- or diet-dependent obesity and insulin resistance (IR). We also found that conditional loss of AnkB in both white (WAT) and brown (BAT) adipose tissue (AT) in mice (AT-AnkB KO) results in age-dependent obesity with WAT hypertrophy, lipotoxicity, systemic inflammation, and IR. We delineated that defects in the internalization of the glucose transporter GLUT4 in WAT, which resulted from deficits in AnkB, caused cell-autonomous WAT hyperplasia and ectopic lipid deposition in peripheral tissues. AT-AnkB KO mice also exhibit lower energy expenditure (EE) before the onset of obesity, which is concomitant with reduced BAT mitochondrial content and brown adipocyte whitening. However, whether primary BAT dysfunction caused by AnkB deficits contribute to metabolic syndrome in these mice and the roles of AnkB in BAT is unknown. Here, we present evidence of a cell-autonomous role of AnkB in lipid metabolism in brown adipocytes. Histological and electron microscopy analyses suggest that conditional AnkB loss in BAT of non-obese mice (BAT-AnkB KO) causes lipid accumulation in BAT characterized by an increase in surface area covered by lipid droplets, a shift towards larger lipid droplets, and a corresponding decrease in mitochondrial content. Differentiated brown adipocytes from mice with total AnkB deficiency (AnkB KO) or from BAT-AnkB KO mice phenocopy the in vivo changes in lipid and mitochondria content, which corresponds with changes in associated gene expression. We will discuss our latest results combining physiology, transcriptomic, proteomic, and cellular analysis that shed light into the pathways modulated by AnkB in BAT and their contribution to systemic metabolic regulation.

Disclosure

A. Aguillard: None. J. Tzeng: None. D. Lorenzo: None.

Funding

National Institutes of Health (3P30DK072476-13S1)
1196-P: Perineuronal Nets in MeA and Arc Are Influenced by Gonadectomy
Authors: ZHANG NAN , XU YONG
Published: June 2021

Background: Recent studies reveal perineuronal nets (PNNs), extracellular matrix specializations that restrict the plasticity of neurons, are influenced by pubertal status. Here we show that PNN are changed by gonadectomy (GDX) both in male and female mice in medial amygdala (MeA) and arcuate nucleus (Arc).

Method: 49 wild type mice are divided into 16 groups by sex, gonadectomy, diet, nutritional status (fed or fasted groups). Fat and lean body mass were assessed by QMR at baseline and before perfusion. Body weight, food intake, and blood glucose were measured weekly for five weeks. Images were captured in MeA, Arc, paraventricular hypothalamus (PVH), anterior hypothalamus (AH), and an intense WFA positive radial area near PVH, which we named ‘periPVH’ after labelling of Wisteria floribunda agglutinin (WFA).

Results: In MeA region, female mice have significantly lower total fluorescence intensity (TFI) (Estimate, 95% Confidence Interval: –448887.02, –578807.10 – –318966.94; p <0.0001) and total number of PNNs (–319.67, –379.34258 – –259.99075: p<0.0001) than male mice. Notably, in female, OVX mice have lower mean fluorescence intensity (MFI) (Mean ± SD: 14.5 ± 3.3 vs. 19.6 ± 4.1; p = 0.003) and TFI (64907.8 (58406.6–96971.3) vs. 123613.9 (83545.9–149131.5); p = 0.015) than sham mice, while the total number of PNNs (Mean ± SD: 63 ± 23 vs. 55 ± 3; p = 0.391) shows no significant difference. Male castration mice have lower total number of PNNs (382 ± 141 vs. 55 ± 22; p <0.0001) and TFI (439343.5 (366431.4–787461.9) vs. 168416.3 (141273.0–258020.8); p <0.0001) than sham mice, while the MFI shows no significant difference. In Arc, mice experiencing GDX have significantly lower MFI (–3.63, –5.61303 – –1.63967; p <0.001), TFI (–28525.8, –45357.46 – –11694.16; P<0.01) or total number of PNNs (–15.3, –29.24 – –1.41; p =0.036) than mice not. PVH, AH, and periPVH don’t show associations with sex, GDX, diet or nutritional status in our observation.

Summary: Our novel discovery indicates the potential role PNN might play in sex hormone regulation in brain.

Disclosure

N. Zhang: None. Y. Xu: None.

Funding

National Institutes of Health (R01DK117281)
1202-P: Hepatic NgBR Is a Potential Resilience Factor for Preventing Obesity-Caused Insulin Resistance
Authors: HU WENQUAN , WANG XIANG , MIAO QING
Published: June 2021

Adiponectin is an adipocyte-secreted protein hormone and prevents the development of insulin resistance. The adiponectin-mediated activation of AMP-activated protein kinase (AMPK) pathway is essential for decreasing the expression of hepatic gluconeogenic enzymes and enhancing the hepatic effects of insulin. However, the resilience factors required to maintain adiponectin-mediated AMPK activation signaling in the liver remain unclear. Recent studies from our laboratory suggest that NgBR plays a previously unrecognized role in preserving AMPK activation. The loss of NgBR in the obesity liver impairs adiponectin-dependent gluconeogenesis and insulin sensitivity. NgBR hepatocyte-specific knockout (hepKO) mice resemble many features of prediabetes, such as moderately increased fasting blood glucose levels and insulin resistance, as well as facilitating the high-fat diet (HFD)-induced onset of T2D. NgBR was identified as a cell surface receptor for soluble Nogo-B (sNogo-B). Also, NgBR binds the farnesylated form of liver kinase B1 (LKB1-farn), a key regulator of AMPK. NgBR depletion in hepatocytes abolishes the localization of LKB1 in the plasma membrane and impairs AMPK activation, the critical signal for adiponectin-mediated insulin sensitivity. NgBR expression is decreased in the liver of diabetic mice. Similar changes also occur in diabetes patients. The NgBR transcript level is reduced in T2D obese patients’ liver compared to non-T2D obese and lean subjects. Additional in vitro studies show that NgBR deficiency in hepatocyte prevents AMPK activation induced by AdipoRon (an agonist of adiponectin receptor) and increases the gluconeogenesis. Our data suggest that NgBR is a potential resilience factor required for preserving adiponectin-mediated insulin sensitivity and preventing the onset of obesity-caused T2D, and disruption of the NgBR-dependent regulation system leads to impairing gluconeogenesis regulation and insulin sensitivity in the liver.

Disclosure

W. Hu: None. X. Wang: None. Q. Miao: None.

Funding

National Institutes of Health (R01DK112971)
1206-P: Effects of Short-Term Administration of Delta-9-tetrahydrocannabinol on Metabolic Parameters of C57bl/6 Mice
Authors: KURJAN EMILY , OLSON LAWRENCE K. , ALSHAARAWY OMAYMA
Published: June 2021

Cancer and HIV-related cachexias are among the qualifying conditions for medical cannabis use. Although effective to alleviate nausea and vomiting, clinical trials demonstrated little to no impact of cannabinoids on weight gain in patients. Consistent with this, cannabis users have a lower prevalence of obesity in epidemiological studies. Since cannabinoid-1 receptors (CB1R) regulate food intake and adipose tissue thermogenesis, we studied the metabolic effects of a low dose of delta-9-tetrahydrocannabinol (THC), a CB1R agonist and the main bioactive chemical in cannabis, in 8-week old male mice maintained on a 10%-fat-calorie diet. Mice received daily intraperitoneal injections of THC (3 mg/Kg, n = 15) or vehicle (n = 12) just before the dark cycle for 7 days. THC-treated mice gained an average of 1.6 grams compared to 2.6 grams gained by the vehicle-treated mice (p = 0.03). Despite the attenuated weight gain, automated home cage phenotyping revealed an increase in food intake in the 90 minutes after injections in the THC-treated mice (mean = 0.78 vs. 0.53 grams; p = 0.001). No differences, however, were detected in overall light (p = 0.39) or dark-cycle food intake (p = 0.07). THC-treated mice also showed reduced locomotor activity in the dark cycle compared to vehicle-treated mice (p <0.001). There were no robust differences in indirect calorimetry parameters between groups in the dark cycle, whereas the respiratory exchange rates were lower among THC-treated mice during the light cycle (p = 0.01). Gene expression studies revealed reduced CB1R mRNA levels in brown adipose (mean = 0.61; p = 0.02) and liver (mean = 0.30; p = 0.04) of THC-treated mice.

In summary, administration of a low dose of THC was associated with attenuated weight gain in male C57BL/6 mice, possibly through downregulation of CB1R in metabolically active tissues. Future studies will elucidate the effects of chronic THC administration on CB1R expression and thermogenesis under high fat feeding and obesity.

Disclosure

E. Kurjan: n/a. L. K. Olson: None. O. Alshaarawy: None.

Funding

National Institutes of Health (R00AT009156)
1227-P: Association between Fat-to-Muscle Ratio and Insulin Resistance in Adults with Impaired Fasting Glucose
Authors: LAI YUN-JU
Published: June 2021

Background: Body composition measurements are useful for assessing cardiometabolic risk. But the associations of the fat-to-muscle ratio with insulin resistance was not well investigated.

Methods: Adults with impaired fasting glucose were recruited from a community hospital in Taiwan during 2017. Demographics, lifestyle features, and medical history were gathered by well-trained interviewers. All participants underwent comprehensive physical examinations, including a biochemical assay of venous blood specimens and urine samples after an 8-hour overnight fast. Fat-to-muscle ratio was measured using whole-body dual-energy X-ray absorptiometry and calculated as follows: total fat mass (g) divided by total lean mass (g). The homeostasis model assessment for IR (HOMA-IR) was used to evaluate insulin resistance and was calculated as follows: [fasting plasma glucose level (mg/dL) × fasting plasma insulin level (uIU/mL)]/405. Multivariable logistic regression analysis was employed to explore the relation between fat-to-muscle ratio and insulin resistance.

Results: Among 234 participants, the proportion of women was 50.1%, and the mean age was 64.2 ± 10.0 years. The fat-to-muscle ratio significantly differed between men and women (0.38 ± 0.12 vs. 0.62 ± 0.16, respectively, P < 0.001). Insulin resistance is significantly associated with fat-to-muscle ratio increased (P<0.001). The multivariable-adjusted odds ratio of fat-to-muscle ratio for insulin resistance (HOMA-IR ≥ 3) were 65.38 [95% confidence interval (CI): 4.03- >999.999] in men, and 12.73 (95% CI: 2.64- 61.41) in women.

Conclusions: The current study revealed that a high fat-to-muscle ratio was significantly associated with increased risk of insulin resistance in adults with impaired fasting glucose.

Disclosure

Y. Lai: None.
123-OR: Deletion of Both Pcsk1 And Pcsk2 in Beta Cells: Lack of Mature Insulin Drives Beta-Cell Expansion and Dysfunction, but Not Severe Diabetes in Mice
Authors: TAYLOR AUSTIN , CHEN YI-CHUN , PASULA DANIEL , LUCIANI DAN S. , VERCHERE BRUCE
Published: June 2021

Proinsulin (PI) is processed to mature insulin by prohormone convertases 1/3 (Pcsk1) and 2 (Pcsk2). In individuals with T1D and T2D, there is an increase in the circulating PI:insulin ratio. We hypothesized that β-cell Pcsk1 and Pcsk2 deletion would result in β-cell dysfunction, loss of insulin production, and marked hyperglycemia.

Single Pcsk1flox/flox Ins1cre/+ (Pcsk1βKO), Pcsk2flox/flox Ins1cre/+ (Pcsk2βKO), and double Pcsk1flox/flox Pcsk2flox/flox Ins1cre/+ (DPCβKO) β-cell prohormone convertase knockout mice were generated (with respective Pcsk1+/+ Pcsk2+/+ Ins1cre/+ controls) and monitored until 30 weeks old. Pcsk2βKO mice displayed no glycemic phenotype, while Pcsk1βKO mice displayed mild hyperglycemia and impaired glucose tolerance by 26 weeks of age. DPCβKO mice displayed mild hyperglycemia (10.1±1.6 vs. 12.3±2.1 mM; p=0.006) and marked glucose intolerance by 10 weeks of age (AUC: 418±135 vs. 1485±360; p<0.0001). No animals displayed obesity relative to controls. Insulin+ pancreas area was doubled in DPCβKO male mice (p=0.0004) and DPCβKO islets showed early glucose-induced Ca2+ influx and loss of oscillatory Ca2+ flux. Pcsk2βKO islets had unaltered mature insulin, while Pcsk1βKO islets had reduced mature insulin. DPCβKO islets contained no detectable mature insulin by western blot. In contrast, Pcsk2βKO islets had markedly reduced mature islet amyloid polypeptide (IAPP), while Pcsk1βKO islets contained normal mature IAPP levels.

Our results suggest that complete loss of β-cell prohormone processing, including PI processing, can drive β-cell dysfunction and expansion, but only mild diabetes and glucose intolerance. Although Pcsk2 deletion in β cells does not impact glycemia or PI processing, it is required for normal proIAPP processing. In total, our data support the idea that altered β-cell prohormone processing does not impact obesity but can contribute to the pathogenesis of diabetes via β-cell dysfunction.

Disclosure

A. Taylor: None. Y. Chen: None. D. Pasula: None. D. S. Luciani: None. B. Verchere: Advisory Panel; Self; Integrated Nanotherapeutics Inc., Sirona Biochem, Stock/Shareholder; Self; Integrated Nanotherapeutics Inc.

Funding

Canadian Institutes of Health Research
1237-P: Generation of Targeted Nanoparticles for ß-Cell-Selective Delivery of Antioxidant Drugs
Authors: NOVAK ALISSA , CHAKRAVARTHULA TANMAYE NALLAN , CROWDER JUSTIN , ALVES NATHAN J. , BROICHHAGEN JOHANNES , HODSON DAVID , BEDWELL AMANDA , LINNEMANN AMELIA K.
Published: June 2021

β-cells are highly metabolic and vulnerable to a variety of exogenous stressors, many of which elicit the generation of reactive oxygen species (ROS). Endogenous adaptive responses can restore homeostasis after excessive ROS elevation. If the endogenous adaptive response fails, ROS accumulation can cause damage to DNA, proteins, and organelles, ultimately leading to apoptosis. A wealth of evidence supports that ROS accumulation contributes to β-cell dysfunction and destruction during diabetes development. These findings suggest that stimulating the antioxidant response could prevent or treat diabetes. However, limitations exist in that persistent systemic activation of the antioxidant response can perturb the normal second messenger function of ROS, and that exogenous antioxidants have poor bioavailability and lack specificity. To overcome these obstacles, we developed β-cell targeted nanoparticles to selectively deliver antioxidants to β-cells. We conjugated modified Exendin-4 (Ex4) to an amphiphilic polymer, allowing us to generate lipid nanoparticles to deliver small hydrophobic compounds to GLP-1R expressing cells. We assessed β-cell targeting of our nanoparticles using isolated islets from mice expressing tdTomato selectively in the β-cell. Isolated islets were treated with nanoparticles containing a lipid intercalating dye, DiO, and we observed selective DiO accumulation in tdTomato positive cells. We also performed in vivo imaging of live mice injected with targeted or non-targeted nanoparticles containing a near-IR lipid intercalating dye. These experiments demonstrated selective retention of targeted nanoparticles both systemically and in the pancreata of animals 1 hour after tail vein injection. Collectively, we provide evidence that Ex4 coated micelles are selective to β-cells. Future experiments will explore this targeted approach to deliver drugs to stimulate the antioxidant response and reduce β-cell apoptosis under diabetogenic conditions.

Disclosure

A. Novak: None. T. Nallan chakravarthula: None. J. Crowder: None. N. J. Alves: None. J. Broichhagen: None. D. Hodson: None. A. Bedwell: None. A. K. Linnemann: None.
1252-P: Alteration of Alternative Splicing of RYR2 Modulates Insulin Biosynthesis in Pancreatic ß-Cells
Authors: MAKINO MAI , ITAYA-HIRONAKA ASAKO , YAMAUCHI AKIYO , SAKURAMOTO-TSUCHIDA SUMIYO , TAKEDA YOSHINORI , UCHIYAMA TOMOKO , TAKASAWA SHIN
Published: June 2021

In pancreatic β cells, intracellular Ca2+ is essential for insulin biosynthesis. Ryanodine receptors (Ryrs) mediate Ca2+ mobilization from the endoplasmic reticulum. Previously we found that type 2 Ryr (Ryr2; originally called cardiac-type) of three isoforms from separate genes was expressed in pancreatic β cells and that Ryr2 mRNA expressed in the pancreatic β cells was deficient in the region of exon 75, unlike that expressed in the heart. This alternative splicing occurred tissue-specifically, which is presumably due to a unique splice donor site “gg” in intron 75 of Ryr2 gene. In order to clarify the role of the tissue-specific splice variant of Ryr2 on insulin biosynthesis, we constructed the homozygous genome-modified pancreatic β cells which express cardiac RYR2 by changing the splice donor “gg” of RYR2 gene to “gt” in human 1.1B4 pancreatic β cells using the CRISPR/Cas9 system. Insulin content in the culture medium and insulin mRNA level were measured by ELISA and real-time RT-PCR, respectively. The results showed that both insulin and insulin mRNA levels were significantly lower in the genome-modified cells than those in parental 1.1B4 cells. We examined the effect of complementation of Ryr2 by introducing the rat cardiac-type or islet-type Ryr2 expression vector into each cell. Real-time RT-PCR analysis showed that the expression of insulin mRNA was significantly increased in the cells transfected with the islet-type Ryr2 expression vector, whereas that in the cells transfected with the cardiac-type Ryr2 expression vector was not increased. Furthermore, the result of luciferase assay showed that the promoter activity of insulin gene was not decreased in the genome-modified cells as compared with the parental 1.1B4 cells.

In conclusion, those results indicate that exon 75-deficient Ryr2 could be important in the post-transcriptional step of insulin biosynthesis via Ca2+ signaling in pancreatic β cells.

Disclosure

M. Makino: None. A. Itaya-hironaka: None. A. Yamauchi: None. S. Sakuramoto-tsuchida: None. Y. Takeda: None. T. Uchiyama: None. S. Takasawa: None.

Funding

Japan Society for the Promotion of Science (JP19K16543)