Endocrinology, Diabetes, and Metabolism Commons^™

Metabolic Flexibility Across The Spectrum Of Glycemic Regulation In Youth, Fida Bacha, Sara Klinepeter Bartz, Maurice Puyau, Anne Adolph, Susan Sharma

Children’s Nutrition Research Center Staff Publications

BACKGROUNDMetabolic flexibility (MF) refers to the relative ability to utilize lipid and carbohydrate substrates and to transition between them. It is not clear whether MF is impaired in obese youth and what the determining factors are.METHODSWe investigated the determinants of MF (increased respiratory exchange ratio [ΔRER] under insulin-stimulated conditions) in pubertal youth (n = 104; 15.6 ± 1.8 years) with obesity across the spectrum of glucose tolerance compared with normal weight (NW) controls, including body composition (fat-free mass [FFM], %body fat), visceral adipose fat (VAT) (MRI), glycemia, and insulin sensitivity (IS) [3-hour hyperinsulinemic-euglycemic clamp with measurement of lipolysis ([2H5] glycerol), …

Intestinal Stem Cell-Derived Enteroids From Morbidly Obese Patients Preserve Obesity-Related Phenotypes: Elevated Glucose Absorption And Gluconeogenesis, Nesrin M Hasan, Kelli F Johnson, Jianyi Yin, Nicholas W Baetz, Lea Fayad, Vadim Sherman, Sarah E Blutt, Mary K Estes, Vivek Kumbhari, Nicholas C Zachos, Olga Kovbasnjuk

Faculty, Staff and Students Publications

OBJECTIVE: The mechanisms behind the efficacy of bariatric surgery (BS) for treating obesity and type 2 diabetes, particularly with respect to the influence of the small bowel, remain poorly understood. In vitro and animal models are suboptimal with respect to their ability to replicate the human intestinal epithelium under conditions induced by obesity. Human enteroids have the potential to accelerate the development of less invasive anti-obesity therapeutics if they can recapitulate the pathophysiology of obesity. Our aim was to determine whether adult stem cell-derived enteroids preserve obesity-characteristic patient-specific abnormalities in carbohydrate absorption and metabolism.

METHODS: We established 24 enteroid lines …

Glycemic Variability In Patients With Stage Ii-Iii Colon Cancer, Natalie Mandolfo

Theses & Dissertations

Patients with cancer experience metabolic changes such as hypoglycemia, hyperglycemia, and glycemic variability; collectively termed malglycemia. Glycemic variability, defined as fluctuations in glucose, is a marker of metabolic instability. Higher glycemic variability is associated with adverse health outcomes in the general population and in those with diabetes. Little is known about glycemic variability in patients with cancer, especially those with solid tumor malignancies. Glycemic variability is associated with increased infection, shorter periods of remission, and higher mortality in patients with hematological cancer. This body of work describes the concept and measurement of glycemic variability to assess glycemic control in patients …

Stat1 Dissociates Adipose Tissue Inflammation From Insulin Sensitivity In Obesity, Aaron R Cox, Natasha Chernis, David A Bader, Pradip K Saha, Peter M Masschelin, Jessica B Felix, Robert Sharp, Zeqin Lian, Vasanta Putluri, Kimal Rajapakshe, Kang Ho Kim, Dennis T Villareal, Reina Armamento-Villareal, Huaizhu Wu, Cristian Coarfa, Nagireddy Putluri, Sean M Hartig

Faculty, Staff and Students Publications

Obesity fosters low-grade inflammation in white adipose tissue (WAT) that may contribute to the insulin resistance that characterizes type 2 diabetes. However, the causal relationship of these events remains unclear. The established dominance of STAT1 function in the immune response suggests an obligate link between inflammation and the comorbidities of obesity. To this end, we sought to determine how STAT1 activity in white adipocytes affects insulin sensitivity. STAT1 expression in WAT inversely correlated with fasting plasma glucose in both obese mice and humans. Metabolomic and gene expression profiling established STAT1 deletion in adipocytes (STAT1a-KO) enhanced mitochondrial function …

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Estrogen Receptor-Α Expressing Neurons In The Ventrolateral Vmh Regulate Glucose Balance, Yanlin He, Pingwen Xu, Chunmei Wang, Yan Xia, Meng Yu, Yongjie Yang, Kaifan Yu, Xing Cai, Na Qu, Kenji Saito, Julia Wang, Ilirjana Hyseni, Matthew Robertson, Badrajee Piyarathna, Min Gao, Sohaib A Khan, Feng Liu, Rui Chen, Cristian Coarfa, Zhongming Zhao, Qingchun Tong, Zheng Sun, Yong Xu

Children’s Nutrition Research Center Staff Publications

Brain glucose-sensing neurons detect glucose fluctuations and prevent severe hypoglycemia, but mechanisms mediating functions of these glucose-sensing neurons are unclear. Here we report that estrogen receptor-α (ERα)-expressing neurons in the ventrolateral subdivision of the ventromedial hypothalamic nucleus (vlVMH) can sense glucose fluctuations, being glucose-inhibited neurons (GI-ERαvlVMH) or glucose-excited neurons (GE-ERαvlVMH). Hypoglycemia activates GI-ERαvlVMH neurons via the anoctamin 4 channel, and inhibits GE-ERαvlVMH neurons through opening the ATP-sensitive potassium channel. Further, we show that GI-ERαvlVMH neurons preferentially project to the medioposterior arcuate nucleus of the hypothalamus (mpARH) and GE-ERαvlVMH neurons preferentially project to the dorsal Raphe nuclei (DRN). Activation of ERαvlVMH …

Metabolic-Sensing Of The Skeletal Muscle Clock Coordinates Fuel Oxidation, Hongshan Yin, Weini Li, Somik Chatterjee, Xuekai Xiong, Pradip Saha, Vijay Yechoor, Ke Ma

Faculty, Staff and Students Publications

Circadian clock confers temporal control in metabolism, with its disruption leading to the development of insulin resistance. Metabolic substrate utilization in skeletal muscle is coordinated with diurnal nutrient cycles. However, whether the molecular clock is involved in this coordination is largely unknown. Using a myocyte-selective genetic ablation mouse model of the essential clock activator Bmal1, here we identify muscle-intrinsic clock as a sensor of feeding cues to orchestrate skeletal muscle oxidation required for global nutrient flux. Bmal1 in skeletal muscle responds robustly to feeding in vivo and insulin induces its expression. Muscle Bmal1 deficiency impaired the transcriptional control of glucose …

Metabolic Dysregulation In The Atp7b-/- Wilson's Disease Mouse Model, Clavia Ruth Wooton-Kee, Matthew Robertson, Ying Zhou, Bingning Dong, Zhen Sun, Kang Ho Kim, Hailan Liu, Yong Xu, Nagireddy Putluri, Pradip Saha, Cristian Coarfa, David D Moore, Alli M Nuotio-Antar

Faculty, Staff and Students Publications

Inactivating mutations in the copper transporter Atp7b result in Wilson’s disease. The Atp7b−/− mouse develops hallmarks of Wilson’s disease. The activity of several nuclear receptors decreased in Atp7b−/− mice, and nuclear receptors are critical for maintaining metabolic homeostasis. Therefore, we anticipated that Atp7b−/− mice would exhibit altered progression of diet-induced obesity, fatty liver, and insulin resistance. Following 10 wk on a chow or Western-type diet (40% kcal fat), parameters of glucose and lipid homeostasis were measured. Hepatic metabolites were measured by liquid chromatography–mass spectrometry and correlated with transcriptomic data. Atp7b−/− mice fed a chow diet presented …

Malignant Insulinoma With Multiple Liver Metastases And Hypercalcitoninemia In A Patient With Type 2 Diabetes Mellitus Presenting As Recurrent Episodes Of Diaphoresis Due To Severe Hypoglycemia, Marco Ciacciarelli, Gianluca Caruso, Marco Rengo, Piero Maceroni, Carmen Misurale, Eleonora D'Armiento, Cristina Napoli, Alberto Lombardini, Umberto Ceratti, Ruben Manuel Luciano Colunga Biancatelli, Leonardo Calvosa, Romina Milanese, Sonia Ferri, Teresa Massaro, Andrea Larusso, Veronica Sorrentino, Vincenzo Petrozza

Bioelectrics Publications

Insulinoma is an insulin-producing pancreatic neuroendocrine tumor that can be malignant in about 10% of cases. Locoregional invasion, lymph node metastases, or remote metastases are the main criteria of malignant insulinoma. Its incidence in patients with pre-existing diabetes mellitus (DM) is exceptionally rare. In this report, we describe a 66-year-old man with long-standing type 2 DM who presented with recurrent episodes of diaphoresis due to severe hypoglycemia despite the withdrawal of insulin therapy, hypercalcitoninemia, and biochemical and radiological findings suggestive of metastatic malignant insulinoma. Unfortunately, after few days of diazoxide treatment, edema, hypotension, oliguria, and water retention were observed, patient’s …

Nighttime Melatonin Administration And Insulin Sensitivity, Albert Mchugh, Cynthia Cheng, Md, Phd

Phase 1

Introduction: Previous studies have shown melatonin effects on insulin sensitivity, but with conflicting results. The inconsistency between these studies may be due to differences in melatonin dosage and subject age. Low melatonin dosages, generally <5 mg, have been used in prior research. We studied the effect of melatonin 9 mg for 6 weeks on insulin resistance, peripheral microvascular function, and sleep in non-diabetic, non-hypertensive middle-aged and geriatric patients.

Methods: Subjects with a history of hypertension or diabetes were excluded from the study. The geriatric cohort included 5 subjects 60-80 years old while the younger cohort was comprised of 14 subjects age 27-45 years old. Fifteen subjects were randomized to the melatonin treatment group and took 9 mg of controlled-release melatonin by mouth 30 minutes before bedtime for 6 weeks; the four subjects in …

Detection Of Human Plasma Glucose Using A Self-Powered Glucose Biosensor, Gymama Slaughter, Tanmay Kulkarni

Bioelectrics Publications

This work presents the characterization of a self-powered glucose biosensor using individual sequential assays of human plasma glucose obtained from diabetic patients. The self-powered glucose biosensor is exploited to optimize the assay parameters for sensing plasma glucose levels. In particular, the biofuel cell component of the system at pH 7.4, 37 °C generates a power density directly proportional to plasma glucose and exhibited a maximum power density of 0.462 mW·cm⁻² at a cell voltage of 0.213 V in 5 mM plasma glucose. Plasma glucose is further sensed by monitoring the charge/discharge frequency (Hz) of the integrated capacitor functioning as …

The Effect Of Dehydration On Metabolism And Energy Substrate Utilization, Zachary Robert Lewis

Graduate Theses and Dissertations

The purpose of this study was to measure hormonal and metabolic markers in humans to see if simulating dehydration would emulate measures that are seen in prediabetic humans. 60 volunteers were divided into equal categories by sex and body mass index of normal or overweight. Participants completed two oral glucose tolerance tests (OGTT) after being intravenously infused with a isotonic or hypertonic saline solution for 120 minutes in a counter balanced order. All trials began with a euhydrated subject with a urine specific gravity (USG)

The Dual Role Of Group V Secretory Phospholipase A2 In Pancreatic Β-Cells, Preetha Shridas, Victoria P. Noffsinger, Andrea C. Trumbauer, Nancy R. Webb

Saha Cardiovascular Research Center Faculty Publications

Purpose

Group X (GX) and group V (GV) secretory phospholipase A₂ (sPLA₂) potently release arachidonic acid (AA) from the plasma membrane of intact cells. We previously demonstrated that GX sPLA₂ negatively regulates glucose-stimulated insulin secretion (GSIS) by a prostaglandin E2 (PGE2)-dependent mechanism. In this study we investigated whether GV sPLA₂ similarly regulates GSIS.

Methods

GSIS and pancreatic islet-size were assessed in wild-type (WT) and GV sPLA₂-knock out (GV KO) mice. GSIS was also assessed ex vivo in isolated islets and in vitro using MIN6 pancreatic beta cell lines with or without GV sPLA …

The Role Of Progesterone Receptor Membrane Component 1 In Receptor Trafficking And Disease, Kaia K. Hampton

Theses and Dissertations--Pharmacology and Nutritional Sciences

The progesterone receptor membrane component 1 (PGRMC1) is a multifunctional protein with a heme-binding domain that promotes cellular signaling via receptor trafficking, and is essential for some elements of tumor growth and metastasis. PGRMC1 is upregulated in breast, colon, lung and thyroid tumors. We expanded the analysis of PGRMC1 in the clinical setting, and report the first analysis of PGRMC1 in human oral cavity and ovarian tumors and found PGRMC1 to correlate with lung and ovarian cancer patient survival. Furthermore, we discovered a specific role for PGRMC1 in cancer stem cell viability. PGRMC1 directly associates with the epidermal growth factor …

Effects Of Nox-1 Inhibition On Real-Time Blood Nitric Oxide And Hydrogen Peroxide In Acute Hyperglycemia, Ashley Mawhinney

PCOM Biomedical Studies Student Scholarship

Hyperglycemia has been associated with vascular endothelial dysfunction in part by a reduction in nitric oxide (NO) production and increased oxidative stress (e.g., increased superoxide (SO) and hydrogen peroxide (H₂O₂). Endothelial-derived NO can be significantly reduced by increased SO/H₂O₂ in part by the activation of NADPH oxidase during hyperglycemia. Of the 7 NADPH oxidase isoforms, NADPH oxidase isoform 1 (NOX1) is mainly expressed in the vasculature and may play a major role in hyperglycemia induced oxidative stress and vascular endothelial dysfunction. This hypothesis was tested by measuring blood NO and H2O2 levels in …

Genetic Modification Of Human Mesenchymal Stem Cells Helps To Reduce Adiposity And Improve Glucose Tolerance In An Obese Diabetic Mouse Model., Sabyasachi Sen, Cleyton C Domingues, Carol Rouphael, Cyril Chou, Chul Kim, Nagendra Yadava

Medicine Faculty Publications

INTRODUCTION: Human mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into fat, muscle, bone and cartilage cells. Exposure of subcutaneous abdominal adipose tissue derived AD-MSCs to high glucose (HG) leads to superoxide accumulation and up-regulation of inflammatory molecules. Our aim was to inquire how HG exposure affects MSCs differentiation and whether the mechanism is reversible.

METHODS: We exposed human adipose tissue derived MSCs to HG (25 mM) and compared it to normal glucose (NG, 5.5 mM) exposed cells at 7, 10 and 14 days. We examined mitochondrial superoxide accumulation (Mitosox-Red), cellular oxygen consumption rate (OCR, Seahorse) and gene …

Increasing Adipocyte Lipoprotein Lipase Improves Glucose Metabolism In High Fat Diet-Induced Obesity, R. Grace Walton, Beibei Zhu, Resat Unal, Michael Spencer, Manjula Sunkara, Andrew J. Morris, Richard Charnigo, Wendy S. Katz, Alan Daugherty, Deborah A. Howatt, Philip A. Kern, Brian S. Finlin

Barnstable Brown Diabetes Center Faculty Publications

Lipid accumulation in liver and skeletal muscle contributes to co-morbidities associated with diabetes and obesity. We made a transgenic mouse in which the adiponectin (Adipoq) promoter drives expression of lipoprotein lipase (LPL) in adipocytes to potentially increase adipose tissue lipid storage. These mice (Adipoq-LPL) have improved glucose and insulin tolerance as well as increased energy expenditure when challenged with a high fat diet (HFD). To identify the mechanism(s) involved, we determined whether the Adipoq-LPL mice diverted dietary lipid to adipose tissue to reduce peripheral lipotoxicity, but we found no evidence for this. Instead, characterization …

Diabetes Self-Management Education For Adolescent Patients: The Importance Of A Developmentally Sensitive Approach, Laura Mumme

Senior Honors Theses

The attention of healthcare providers to the developmental level of adolescent patients with type one diabetes (T1D) maximizes effective patient education and glycemic control. Due to the dynamic changes that occur in the mind and body during adolescence, self-care for adolescent T1D patients is overwhelming as it envelopes activities of everyday life. The disease process and the unique aspects of adolescence in relation to T1D are important for caregivers to consider. Developmentally appropriate teaching during the initial onset of the disease must inform the patient and the patient’s family of the basics of the disease process and the daily care …

Association Of Demographic Characteristics With Gestational Diabetes Mellitus And Gestational Hypertension In Ohio During 2012, Jared D. Klein

Master of Public Health Program Student Publications

Background: Gestational Diabetes Mellitus (GDM) and Gestational Hypertension (GHTN) are serious conditions that can arise during pregnancy. Both of these disorders can cause detrimental health effects to both mother and newborn. Methods: Ohio vital statistics birth data was obtained from Public Health- Dayton and Montgomery County. The data set included 137,268 women who gave birth during 2012 in Ohio and had a known GDM and/or GHTN status. IBM Statistical Package for Social Sciences for Mac Version 20 (SPSS, IBM, 2011) was used to analyze the data. Descriptive statistics, odds ratios, chi-square analyses, and multivariate logistic forward stepwise regressions were calculated …

Regulation Of Glucose Homeostasis By The Phlpp1 Phosphatase, Kara L. Larson

Theses and Dissertations--Molecular and Cellular Biochemistry

Type 2 diabetes mellitus is a metabolic disease that affects one in ten people in the United States. It is caused by a combination of genetics and lifestyle factors. Disease progression begins with insulin resistance in peripheral tissues followed by pancreatic beta-cell failure. The mechanisms behind disease progression are not completely understood. PH domain leucine rich repeat protein phosphatase 1 (PHLPP1) is a known regulator of Akt and other members of the AGC kinase family. Akt has been established to play a role in numerous metabolic signaling pathways, including insulin action. It is hypothesized that as a regulator of Akt, …

Cardiac Fibroblast-Dependent Extracellular Matrix Accumulation Is Associated With Diastolic Stiffness In Type 2 Diabetes., Kirk R. Hutchinson, C. Kevin Lord, T. Aaron West, James A. Stewart

CAS Publications

Cardiovascular complications are a leading cause of death in patients with type 2 diabetes mellitus (T2DM). Diastolic dysfunction is one of the earliest manifestations of diabetes-induced changes in left ventricular (LV) function, and results from a reduced rate of relaxation and increased stiffness. The mechanisms responsible for increased stiffness are not completely understood. Chronic hyperglycemia, advanced glycation endproducts (AGEs), and increased levels of proinflammatory and profibrotic cytokines are molecular pathways known to be involved in regulating extracellular matrix (ECM) synthesis and accumulation resulting in increased LV diastolic stiffness. Experiments were conducted using a genetically-induced mouse model of T2DM generated by …

Lipid Targets In Clinical Practice: Successes, Failures And Lessons To Be Learned, M Dunne, Oscar Mac Ananey, V Maher

Articles

Abstract

INTRODUCTION:

Optimal risk factor control is integral to managing patients with proven coronary heart disease (CHD+) and for those at risk of coronary heart disease (CHD-). The primary aim of the study was to assess the success rate of reaching lipid risk factor targets in a multiple risk factor clinic.

METHODS:

A retrospective audit was conducted in 488 patients (CHD+, n = 112; CHD-, n = 376) who attended the Cardiovascular Risk Factor Clinic at Tallaght Hospital, Dublin in 2009 and 2010.

RESULTS:

Risk factor targets achieved in CHD+ and CHD- patients were LDLc (54/62 %), HDLc (67/67 %), …

Is Bisphenol-A Exposure During Pregnancy Associated With Blood Glucose Levels Or Diagnosis Of Gestational Diabetes?, Candace A. Robledo, Jennifer D. Peck, Julie A. Stoner, Hélène Carabin, Linda Cowan, Holger M. Koch, Jean R. Goodman

School of Medicine Publications

Recent epidemiological studies indicate bisphenol A (BPA), an estrogenic chemical used in production of epoxy, polycarbonate, and plastic may increase risk of insulin resistance and type 2 diabetes. Exposure to BPA during pregnancy may contribute to development of gestational diabetes mellitus (GDM), a precursor to type 2 diabetes in women. This pilot study examined the association between BPA exposure, fasting blood glucose levels (FBG), and GDM diagnosis during pregnancy. Banked urine samples from 22 cases of GDM and 72 controls were analyzed for total (free BPA + conjugates) urinary BPA concentrations (μg/L). FBG levels (mg/dl) were obtained from 1-h 50-g …

Transfusion Of Cxcr4-Primed Endothelial Progenitor Cells Reduces Cerebral Ischemic Damage And Promotes Repair In Db/Db Diabetic Mice, Ji Chen, Jianying Chen, Shuzhen Chen, Cheng Zhang, Liangqing Zhang, Xiang Xiao, Avik Das, Yuhui Zhao, Bin Yuan, Mariana Morris, Bin Zhao, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

This study investigated the role of stromal cell-derived factor-1α (SDF-1α)/CXC chemokine receptor 4 (CXCR4) axis in brain and endothelial progenitor cells (EPCs), and explored the efficacy of CXCR4 primed EPCs in treating ischemic stroke in diabetes. The db/db diabetic and db/+ mice were used in this study. Levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were measured. Brain SDF-1α and CXCR4 expression were quantified at basal and after middle cerebral artery occlusion (MCAO). In in vitro study, EPCs were transfected with adenovirus carrying null (Ad-null) or CXCR4 (Ad-CXCR4) followed with high glucose (HG) treatment for 4 days. For pathway block …