Endocrine System Diseases Commons^™

Loss Of Bone Morphogenetic Protein-Binding Endothelial Regulator Causes Insulin Resistance, Hua Mao, Luge Li, Qiying Fan, Aude Angelini, Pradip K Saha, Huaizhu Wu, Christie M Ballantyne, Sean M Hartig, Liang Xie, Xinchun Pi

Faculty, Staff and Students Publications

Accumulating evidence suggests that chronic inflammation of metabolic tissues plays a causal role in obesity-induced insulin resistance. Yet, how specific endothelial factors impact metabolic tissues remains undefined. Bone morphogenetic protein (BMP)–binding endothelial regulator (BMPER) adapts endothelial cells to inflammatory stress in diverse organ microenvironments. Here, we demonstrate that BMPER is a driver of insulin sensitivity. Both global and endothelial cell-specific inducible knockout of BMPER cause hyperinsulinemia, glucose intolerance and insulin resistance without increasing inflammation in metabolic tissues in mice. BMPER can directly activate insulin signaling, which requires its internalization and interaction with Niemann-Pick C1 (NPC1), an integral membrane protein that …

Testosterone Therapy And Bone Quality In Men With Diabetes And Hypogonadism: Study Design And Protocol, Vittoria Russo, Georgia Colleluori, Rui Chen, Sanjay Mediwala, Clifford Qualls, Michael Liebschner, Dennis T Villareal, Reina Armamento-Villareal

Faculty, Staff and Students Publications

CONTEXT: Type 2 diabetes mellitus (T2D) is often accompanied by male hypogonadism and both conditions are associated with increased risk for fractures. Testosterone (T) has been shown to improve the bone health of hypogonadal men but has not been tested in patients who also have T2D in addition to low T. To date, there is no treatment that is specifically recommended for bone disease among patients with T2D. This study will evaluate the effect of T therapy on the bone health of male veterans with low T who also have T2D.

METHODS: This is a randomized double-blind placebo-controlled trial of …

Association Of Baseline Characteristics With Insulin Sensitivity And Β-Cell Function In The Glycemia Reduction Approaches In Diabetes: A Comparative Effectiveness (Grade) Study Cohort, Neda Rasouli, Naji Younes, Kristina M Utzschneider, Silvio E Inzucchi, Ashok Balasubramanyam, Andrea L Cherrington, Faramarz Ismail-Beigi, Robert M Cohen, Darin E Olson, Ralph A Defronzo, William H Herman, John M Lachin, Steven E Kahn

Faculty, Staff and Students Publications

OBJECTIVE: We investigated sex and racial differences in insulin sensitivity, β-cell function, and glycated hemoglobin (HbA

RESEARCH DESIGN AND METHODS: This is a cross-sectional analysis of baseline data from 3,108 GRADE (Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study) participants. All had type 2 diabetes diagnosedβ-cell function were evaluated using the HOMA of insulin sensitivity and estimates from oral glucose tolerance tests, including the Matsuda Index, insulinogenic index, C-peptide index, and oral disposition index (DI).

RESULTS: The cohort was 56.6 ± 10 years of age (mean ± SD), 63.8% male, with BMI 34.2 ± 6.7 kg/m

CONCLUSIONS: In the …

The E3 Ligase Traf4 Promotes Igf Signaling By Mediating Atypical Ubiquitination Of Irs-1, Wenjuan Yu, Ramesh Singh, Zhao Wang, Bert W O'Malley, Ping Yi

Faculty, Staff and Students Publications

Insulin-like growth factor (IGF) is a potent mitogen that activates the IGF receptor (IGFR)/insulin receptor substrate (IRS) axis, thus stimulating growth in normal cells and uncontrolled cell proliferation in cancer. Posttranslational modifications of IRS such as ubiquitination tightly control IGF signaling, and we previously identified IRS-1 as a potential substrate for the E3 ubiquitin ligase TRAF4 using an unbiased screen. Here we provide evidence that TRAF4-mediated ubiquitination of IRS-1 is physiologically relevant and crucial for IGF signal transduction. Through site-directed mutagenesis we found that TRAF4 promotes an atypical K29-linked ubiquitination at the C-terminal end of IRS-1. Its depletion abolishes AKT …

Mir-30a Targets Gene Networks That Promote Browning Of Human And Mouse Adipocytes, Pradip K Saha, Mark P Hamilton, Kimal Rajapakshe, Vasanta Putluri, Jessica B Felix, Peter Masschelin, Aaron R Cox, Mandeep Bajaj, Nagireddy Putluri, Cristian Coarfa, Sean M Hartig

Faculty, Staff and Students Publications

MicroRNA-30a (miR-30a) impacts adipocyte function, and its expression in white adipose tissue (WAT) correlates with insulin sensitivity in obesity. Bioinformatic analysis demonstrates that miR-30a expression contributes to 2% of all miRNA expression in human tissues. However, molecular mechanisms of miR-30a function in fat cells remain unclear. Here, we expanded our understanding of how miR-30a expression contributes to antidiabetic peroxisome proliferator-activated receptor-γ (PPARγ) agonist activity and metabolic functions in adipocytes. We found that WAT isolated from diabetic patients shows reduced miR-30a levels and diminished expression of the canonical PPARγ target genes ADIPOQ and FABP4 relative to lean counterparts. In human adipocytes, …

Glycemic Control And Infections Among Us Hemodialysis Patients With Diabetes Mellitus, Jinnie J Rhee, Yuanchao Zheng, Sai Liu, Maria E Montez-Rath, Richard J Hamill, Julie H Ishida, Wolfgang C Winkelmayer

Faculty, Staff and Students Publications

INTRODUCTION: Patients with diabetes mellitus (DM) on hemodialysis (HD) may be particularly vulnerable to infections.

METHODS: We used merged data from the United States Renal Data System and electronic health records data from a large US dialysis provider to retrospectively examine the association between glycemic control and infections in these patients. Adult patients with DM aged ≥18 years who initiated in-center maintenance HD treatment from 2006 to 2011 and survived >90 days were included. Quarterly mean time-averaged hemoglobin A1c (HbA1c) values were categorized into

RESULTS: In a cohort of 33,753 eligible patients, those with higher HbA1c levels had higher rates …

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 …

The Impact Of Diabetic Foot Ulcers And Unilateral Offloading Footwear On Gait In People With Diabetes, Erica Ling, Brian Lepow, He Zhou, Ana Enriquez, Ashley Mullen, Bijan Najafi

Faculty, Staff and Students Publications

BACKGROUND: Unilateral offloading footwear prescribed to patients with diabetic foot ulcers elevates one limb relative to the other, which may lead to limp and abnormal gait. This study investigated whether the unilateral foot ulcer and offloading combination negatively impacts gait function beyond diabetic peripheral neuropathy.

METHODS: Eighty-six participants were recruited in 3 groups: 12 with diabetic peripheral neuropathy and unilateral foot ulcers wearing offloading footwear (offloading group, age = 55.6 ± 9.5 years, BMI = 30.9 ± 4.5 kg/m

FINDINGS: The offloading group exhibited deteriorated gait function compared to the non-diabetic group (p < 0.005, Cohen's effect size d = 0.90-2.61). They also had decreased gait speed (p < 0.001, d = 1.79) and stride length (p < 0.001, d = 1.76), as well as increased gait cycle time (p < 0.001, d = 1.67) and limp (p < 0.050, d = 0.72-1.49) compared to the neuropathy group. The offloading group showed increased gait unsteadiness compared to the neuropathy group, but the difference did not reach statistical significance in our samples.

INTERPRETATION: This study demonstrated that while diabetic …

The Acute Effect Of Water Intake On Glucose Regulation In Low Drinkers, Adam David Seal

Graduate Theses and Dissertations

Previous evidence suggests the hormone arginine vasopressin (AVP) may be a modifiable factor contributing to hyperglycemia. Significant differences in urine concentration and copeptin, a marker for AVP, have been observed between low and high water drinkers. Purpose: The purpose was to investigate the acute effect of adequate water intake on glucose regulation in low drinkers. Methods: 7 healthy (5 males, 2 female) low drinkers were recruited using a water frequency questionnaire (WFQ), spot and 24-h urine sample (age 43±6 y, BMI 30.9±3, WFQ volume 823±403 mL∙d-1, 24 h Uosm 961±105 mmol∙kg-1, copeptin 8.17±3.05 pmol∙L-1). During two experimental protocols, participants remained …

Ethnic Differences In Maternal Adipokines During Normal Pregnancy, Xinhua Chen, Theresa O Scholl

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Two adipokines (adiponectin and resistin) have opposite relations with insulin resistance and inflammation. Our major focus was to determine whether there were detectable ethnic differences in maternal adipokines during pregnancy. We also explored the correlation of the adipokines with maternal glucose homeostasis, blood pressure and anthropometric parameters. Pregnant women (n = 1634) were from a large prospective cohort study in Camden NJ (African-American 36.8%; Hispanic 47.6%; Caucasian 15.6%). Serum adiponectin and resistin were measured at entry (week 16.8) and the 3rd trimester (week 30.7) using the Luminex xMapTechnology. Significant differences were observed among ethnic groups, controlling for confounding variables. African …

Metabolic Reprogramming Induced By Ketone Bodies Diminishes Pancreatic Cancer Cachexia, Surendra K. Shukla, Teklab Gebregiworgis, Vinee Purohit, Nina V. Chaika, Venugopal Gunda, Prakash Radhakrishnan, Kamiya Mehla, Iraklis I. Pipinos, Robert Powers, Fang Yu, Pankaj K. Singh

Robert Powers Publications

Background: Aberrant energy metabolism is a hallmark of cancer. To fulfill the increased energy requirements, tumor cells secrete cytokines/factors inducing muscle and fat degradation in cancer patients, a condition known as cancer cachexia. It accounts for nearly 20% of all cancer-related deaths. However, the mechanistic basis of cancer cachexia and therapies targeting cancer cachexia thus far remain elusive. A ketogenic diet, a high-fat and low-carbohydrate diet that elevates circulating levels of ketone bodies (i.e., acetoacetate, β-hydroxybutyrate, and acetone), serves as an alternative energy source. It has also been proposed that a ketogenic diet leads to systemic metabolic changes. Keeping in …