Biochemical Phenomena, Metabolism, and Nutrition Commons^™

N-Acetylaspartate From Fat Cells Regulates Postprandial Body Temperature, Jessica B Felix, Pradip K Saha, Evelyn L De Groot, Lin Tan, Robert Sharp, Elizabeth S Anaya, Yafang Li, Holly Quang, Nooshin Saidi, Layla Abushamat, Christie M Ballantyne, Christopher I Amos, Philip L Lorenzi, Samuel Klein, Xia Gao, Sean M Hartig

Faculty, Staff and Students Publications

N-acetylaspartate (NAA), the brain’s second most abundant metabolite, provides essential substrates for myelination through its hydrolysis1. However, the physiological roles of NAA in other tissues remain unknown. Here, we show that aspartoacylase (ASPA) expression in white adipose tissue (WAT) governs blood NAA levels for postprandial body temperature regulation. Genetic ablation of Aspa in mice resulted in systemically elevated NAA levels, and the ensuing accumulation in WAT stimulated pyrimidine production. Stable isotope tracing confirmed higher incorporation of glucose-derived carbon into pyrimidine metabolites in Aspa knockout cells. Additionally, serum NAA levels positively correlated with the abundance of the pyrimidine …

The Small Gtpase Rap1 In Pomc Neurons Regulates Leptin Actions And Glucose Metabolism, Kentaro Kaneko, Weisheng Lu, Yong Xu, Alexei Morozov, Makoto Fukuda

Faculty, Staff and Students Publications

The hypothalamic leptin-proopiomelanocortin (POMC) pathway is critical for regulating metabolism. POMC neurons in the arcuate nucleus respond to leptin and play a pivotal role in mediating energy and glucose balance. However, during diet-induced obesity (DIO), these neurons often develop resistance to exogenous leptin. Recently, the small GTPase Rap1 has been implicated as an inhibitor of neuronal leptin signaling; however, its specific role within POMC neurons remains unexplored. We generated tamoxifen-inducible, POMC neuron-specific Rap1 knockout mice to selectively delete both Rap1a and Rap1b isoforms in POMC neurons. By analyzing these mice through metabolic phenotyping, immunohistochemistry, and biochemical assays, we show that …

Fetal Sex Effects On Maternal Health Can Now Be Tested Via Randomization: A First-In-Class Illustration In Cows On Glucoregulatory Outcomes, Aridany Suarez-Trujillo, Colby J Vorland, Griffin T Nicholls, Daniella E Chusyd, Chelsie Parker, Lilian Golzarri-Arroyo, Sophia Swann, Bethany J Funnell, Kara R Stewart, David B Allison

Children’s Nutrition Research Center Staff Publications

Background: The maternal-offspring relationship, such as whether fetal sex influences maternal health, is essential to explore to advance prenatal and maternal health. While associations exist between fetal sex and maternal health outcomes, it is unclear whether these reflect a causal relationship.

Objective: To demonstrate that fetal sex can be randomly assigned to test the causal effect of fetal sex on maternal outcomes.

Methods: Holstein dairy cows were stratified and randomized using sealed opaque envelopes to be artificially inseminated with either X- or Y-sorted bull semen until 40 cows became pregnant. Monthly body weight measurements were recorded, and an intravenous glucose …

Translational Potential Of Mouse Models Of Human Metabolic Disease, I Sadaf Farooqi, Yong Xu

Children’s Nutrition Research Center Staff Publications

Obesity causes significant morbidity and mortality globally. Research in the last three decades has delivered a step-change in our understanding of the fundamental mechanisms that regulate energy homeostasis, building on foundational discoveries in mouse models of metabolic disease. However, not all findings made in rodents have translated to humans, hampering drug discovery in this field. Here, we review how studies in mice and humans have informed our current framework for understanding energy homeostasis, discuss their challenges and limitations, and offer a perspective on how human studies may play an increasingly important role in the discovery of disease mechanisms and identification …

Mitochondria Regulate Proliferation In Adult Cardiac Myocytes, Gregory B Waypa, Kimberly A Smith, Paul T Mungai, Vincent J Dudley, Kathryn A Helmin, Benjamin D Singer, Clara Bien Peek, Joseph Bass, Lauren Nelson, Sanjiv J Shah, Gaston Ofman, J Andrew Wasserstrom, William A Muller, Alexander V Misharin, G R Scott Budinger, Hiam Abdala-Valencia, Navdeep S Chandel, Danijela Dokic, Elizabeth Bartom, Shuang Zhang, Yuki Tatekoshi, Amir Mahmoodzadeh, Hossein Ardehali, Edward B Thorp, Paul T Schumacker

Faculty, Staff and Student Publications

Newborn mammalian cardiomyocytes quickly transition from a fetal to an adult phenotype that utilizes mitochondrial oxidative phosphorylation but loses mitotic capacity. We tested whether forced reversal of adult cardiomyocytes back to a fetal glycolytic phenotype would restore proliferative capacity. We deleted Uqcrfs1 (mitochondrial Rieske iron-sulfur protein, RISP) in hearts of adult mice. As RISP protein decreased, heart mitochondrial function declined, and glucose utilization increased. Simultaneously, the hearts underwent hyperplastic remodeling during which cardiomyocyte number doubled without cellular hypertrophy. Cellular energy supply was preserved, AMPK activation was absent, and mTOR activation was evident. In ischemic hearts with RISP deletion, new cardiomyocytes …

An Estrogen Receptor Α-Derived Peptide Improves Glucose Homeostasis During Obesity, Wanbao Yang, Wen Jiang, Wang Liao, Hui Yan, Weiqi Ai, Quan Pan, Wesley A Brashear, Yong Xu, Ling He, Shaodong Guo

Faculty, Staff and Students Publications

Estrogen receptor α (ERα) plays a crucial role in regulating glucose and energy homeostasis during type 2 diabetes mellitus (T2DM). However, the underlying mechanisms remain incompletely understood. Here we find a ligand-independent effect of ERα on the regulation of glucose homeostasis. Deficiency of ERα in the liver impairs glucose homeostasis in male, female, and ovariectomized (OVX) female mice. Mechanistic studies reveal that ERα promotes hepatic insulin sensitivity by suppressing ubiquitination-induced IRS1 degradation. The ERα 1-280 domain mediates the ligand-independent effect of ERα on insulin sensitivity. Furthermore, we identify a peptide based on ERα 1-280 domain and find that ERα-derived peptide …

Glycemia And Gluconeogenesis With Metformin And Liraglutide: A Randomized Trial In Youth-Onset Type 2 Diabetes, Katrina B Dietsche, Sheela N Magge, Sydney A Dixon, Faith S Davis, Andrea Krenek, Aruba Chowdhury, Lilian Mabundo, Michael Stagliano, Amber B Courville, Shanna Yang, Sara Turner, Hongyi Cai, Kannan Kasturi, Arthur S Sherman, Joon Ha, Eileen Shouppe, Mary Walter, Peter J Walter, Kong Y Chen, Robert J Brychta, Cody Peer, Yi Zeng, William Figg, Fran Cogen, D Elizabeth Estrada, Shaji Chacko, Stephanie T Chung

Children’s Nutrition Research Center Staff Publications

OBJECTIVE: Elevated rates of gluconeogenesis are an early pathogenic feature of youth-onset type 2 diabetes (Y-T2D), but targeted first-line therapies are suboptimal, especially in African American (AA) youth. We evaluated glucose-lowering mechanisms of metformin and liraglutide by measuring rates of gluconeogenesis and β-cell function after therapy in AA Y-T2D.

METHODS: In this parallel randomized clinical trial, 22 youth with Y-T2D-age 15.3 ± 2.1 years (mean ± SD), 68% female, body mass index (BMI) 40.1 ± 7.9 kg/m2, duration of diagnosis 1.8 ± 1.3 years-were randomized to metformin alone (Met) or metformin + liraglutide (Lira) (Met + Lira) and evaluated before …

Increased Plasma Branched Short-Chain Fatty Acids And Improved Glucose Homeostasis: The Microbiome And Insulin Longitudinal Evaluation Study (Miles), Arianne Aslamy, Alexis C Wood, Elizabeth T Jensen, Alain G Bertoni, Patricia A Sheridan, Kari E Wong, Gautam Ramesh, Jerome I Rotter, Yii-Der I Chen, Mark O Goodarzi

Faculty, Staff and Students Publications

Short-chain fatty acids (SCFAs) have been extensively studied for potential beneficial roles in glucose homeostasis and risk of diabetes; however, most of this research has focused on butyrate, acetate, and propionate. The effect on metabolism of branched SCFAs (BSCFAs; isobutyrate, isovalerate, and methylbutyrate) is largely unknown. In a cohort of 219 non-Hispanic White participants and 126 African American participants, we examined the association of BSCFA with dysglycemia (prediabetes and diabetes) and oral glucose tolerance test-based measures of glucose and insulin homeostasis, as well as with demographic, anthropometric, lifestyle, and lipid traits, and other SCFAs. We observed a bimodal distribution of …

Adverse Metabolic Phenotypes In Parenterally Fed Neonatal Pigs Do Not Persist Into Adolescence, Sarah K Elefson, Barbara Stoll, Teresa A Davis, Marta L Fiorotto, Samer W El-Kadi, Kenneth Genovese, Thomas Thymann, Per T Sangild, Douglas G Burrin

Faculty, Staff and Students Publications

BACKGROUND: Nutrition during fetal and neonatal life is an important determinant for the risk of adult-onset diseases, especially type 2 diabetes and obesity.

OBJECTIVES: We aimed to determine whether total parenteral nutrition (TPN) compared with enteral formula feeding [enteral nutrition (EN)] in term piglets during the first 2 wk after birth would increase the long-term (5-mo) development of metabolic syndrome phenotypes with adverse glucose homeostasis, fatty liver disease, and obesity.

METHODS: Neonatal female pigs were administered TPN (n = 12) or fed enterally with a liquid enteral milk-replacer formula (EN, n = 12) for 14 d. After transitioning TPN pigs …

Glucose Metabolism In Posterior Cingulate Cortex Has Supplementary Value To Predict The Progression Of Cognitively Unimpaired To Dementia Due To Alzheimer’S Disease: An Exploratory Study Of 18f-Fdg-Pet, Qi Zhang, Chunqiu Fan, Luyao Wang, Taoran Li, Min Wang, Ying Han, Jiehui Jiang, Alzheimer’S Disease Neuroimaging Initiative

Faculty, Staff and Student Publications

Amyloid-β (Aβ) and tau are important biomarkers to predict the progression of cognitively unimpaired (CU) to dementia due to Alzheimer's disease (AD), according to the diagnosis framework from the US National Institute on Aging and the Alzheimer's Association (NIA-AA). However, it is clinically difficult to predict those subjects who were already with Aβ positive (A +) or tau positive (T +). As a typical characteristic of neurodegeneration in the diagnosis framework, the hypometabolism of the posterior cingulate cortex (PCC) has significant clinical value in the early prediction and prevention of AD. In this paper, we proposed the glucose metabolism in …

Leptin Reduction As A Required Component For Weight Loss, Shangang Zhao, Na Li, Wei Xiong, Guannan Li, Sijia He, Zhuzhen Zhang, Qingzhang Zhu, Nisi Jiang, Christian Ikejiofor, Yi Zhu, May-Yun Wang, Xianlin Han, Ningyang Zhang, Carolina Solis-Herrera, Christine Kusminski, Zhiqiang An, Joel K Elmquist, Philipp E Scherer

Faculty, Staff and Students Publications

Partial leptin reduction can induce significant weight loss, while weight loss contributes to partial leptin reduction. The cause-and-effect relationship between leptin reduction and weight loss remains to be further elucidated. Here, we show that FGF21 and the glucagon-like peptide 1 receptor (GLP-1R) agonist liraglutide rapidly induced a reduction in leptin. This leptin reduction contributed to the beneficial effects of GLP-1R agonism in metabolic health, as transgenically maintaining leptin levels during treatment partially curtailed the beneficial effects seen with these agonists. Moreover, a higher degree of leptin reduction during treatment, induced by including a leptin neutralizing antibody with either FGF21 or …

Associations Between Avocado Intake And Measures Of Glucose And Insulin Homeostasis In Hispanic Individuals With And Without Type 2 Diabetes: Results From The Hispanic Community Health Study/Study Of Latinos (Hchs/Sol), Mackenzie K Senn, Mark O Goodarzi, Gautam Ramesh, Matthew A Allison, Mariaelisa Graff, Kristin L Young, Gregory A Talavera, Amanda C Mcclain, Tanya P Garcia, Jerome I Rotter, Alexis C Wood

Faculty, Staff and Students Publications

BACKGROUND AND AIMS: To investigate associations between avocado intake and glycemia in adults with Hispanic/Latino ancestry.

METHODS AND RESULTS: The associations of avocado intake with measures of insulin and glucose homeostasis were evaluated in a cross-sectional analysis of up to 14,591 Hispanic/Latino adults, using measures of: average glucose levels (hemoglobin A1c; HbA1c), fasting glucose and insulin, glucose and insulin levels after an oral glucose tolerance test (OGTT), and calculated measures of insulin resistance (HOMA-IR, and HOMA-%β), and insulinogenic index. Associations were assessed using multivariable linear regression models, which controlled for sociodemographic factors and health behaviors, and which were stratified by …

Tfeb And Tfe3 Control Glucose Homeostasis By Regulating Insulin Gene Expression, Adrien Pasquier, Nunzia Pastore, Luca D'Orsi, Rita Colonna, Alessandra Esposito, Veronica Maffia, Rossella De Cegli, Margherita Mutarelli, Susanna Ambrosio, Gennaro Tufano, Antonio Grimaldi, Marcella Cesana, Davide Cacchiarelli, Nathalie Delalleau, Gennaro Napolitano, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

To fulfill their function, pancreatic beta cells require precise nutrient-sensing mechanisms that control insulin production. Transcription factor EB (TFEB) and its homolog TFE3 have emerged as crucial regulators of the adaptive response of cell metabolism to environmental cues. Here, we show that TFEB and TFE3 regulate beta-cell function and insulin gene expression in response to variations in nutrient availability. We found that nutrient deprivation in beta cells promoted TFEB/TFE3 activation, which resulted in suppression of insulin gene expression. TFEB overexpression was sufficient to inhibit insulin transcription, whereas beta cells depleted of both TFEB and TFE3 failed to suppress insulin gene …

Endogenous Renal Adiponectin Drives Gluconeogenesis Through Enhancing Pyruvate And Fatty Acid Utilization, Toshiharu Onodera, May-Yun Wang, Joseph M Rutkowski, Stanislaw Deja, Shiuhwei Chen, Michael S Balzer, Dae-Seok Kim, Xuenan Sun, Yu A An, Bianca C Field, Charlotte Lee, Ei-Ichi Matsuo, Monika Mizerska, Ina Sanjana, Naoto Fujiwara, Christine M Kusminski, Ruth Gordillo, Laurent Gautron, Denise K Marciano, Ming Chang Hu, Shawn C Burgess, Katalin Susztak, Orson W Moe, Philipp E Scherer

Faculty, Staff and Student Publications

Adiponectin is a secretory protein, primarily produced in adipocytes. However, low but detectable expression of adiponectin can be observed in cell types beyond adipocytes, particularly in kidney tubular cells, but its local renal role is unknown. We assessed the impact of renal adiponectin by utilizing male inducible kidney tubular cell-specific adiponectin overexpression or knockout mice. Kidney-specific adiponectin overexpression induces a doubling of phosphoenolpyruvate carboxylase expression and enhanced pyruvate-mediated glucose production, tricarboxylic acid cycle intermediates and an upregulation of fatty acid oxidation (FAO). Inhibition of FAO reduces the adiponectin-induced enhancement of glucose production, highlighting the role of FAO in the induction …

Associations Between Metabolomic Biomarkers Of Avocado Intake And Glycemia In The Multi-Ethnic Study Of Atherosclerosis, Alexis C Wood, Mark O Goodarzi, Mackenzie K Senn, Meghana D Gadgil, Goncalo Graca, Matthew A Allison, Ioanna Tzoulaki, Michael Y Mi, Philip Greenland, Timothy Ebbels, Paul Elliott, Russell P Tracy, David M Herrington, Jerome I Rotter

Faculty, Staff and Students Publications

BACKGROUND: Avocado consumption is linked to better glucose homeostasis, but small associations suggest potential population heterogeneity. Metabolomic data capture the effects of food intake after digestion and metabolism, thus accounting for individual differences in these processes.

OBJECTIVES: To identify metabolomic biomarkers of avocado intake and to examine their associations with glycemia.

METHODS: Baseline data from 6224 multi-ethnic older adults (62% female) included self-reported avocado intake, fasting glucose and insulin, and untargeted plasma proton nuclear magnetic resonance metabolomic features (metabolomic data were available for a randomly selected subset; N = 3438). Subsequently, incident type 2 diabetes (T2D) was assessed over an …

Mapping The Metabolic Reprogramming Induced By Sodium-Glucose Cotransporter 2 Inhibition, Aviram Kogot-Levin, Yael Riahi, Ifat Abramovich, Ofri Mosenzon, Bella Agranovich, Liat Kadosh, Rachel Ben-Haroush Schyr, Doron Kleiman, Liad Hinden, Erol Cerasi, Danny Ben-Zvi, Ernesto Bernal-Mizrachi, Joseph Tam, Eyal Gottlieb, Gil Leibowitz

Faculty, Staff and Student Publications

Diabetes is associated with increased risk for kidney disease, heart failure, and mortality. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) prevent these adverse outcomes; however, the mechanisms involved are not clear. We generated a roadmap of the metabolic alterations that occur in different organs in diabetes and in response to SGLT2i. In vivo metabolic labeling with 13C-glucose in normoglycemic and diabetic mice treated with or without dapagliflozin, followed by metabolomics and metabolic flux analyses, showed that, in diabetes, glycolysis and glucose oxidation are impaired in the kidney, liver, and heart. Treatment with dapagliflozin failed to rescue glycolysis. SGLT2 inhibition increased glucose oxidation …

Cerebral Microdialysis And Glucopenia In Traumatic Brain Injury: A Review, Himanshu Sharma, John P Mcginnis, Katherine E Kabotyanski, Shankar P Gopinath, Jerry C Goodman, Claudia Robertson, Jovany Cruz Navarro

Faculty, Staff and Students Publications

Traditionally, intracranial pressure (ICP) and partial brain tissue oxygenation (PbtO2) have been the primary invasive intracranial measurements used to guide management in patients with severe traumatic brain injury (TBI). After injury however, the brain develops an increased metabolic demand which may require an increment in the oxidative metabolism of glucose. Simultaneously, metabolic, and electrical dysfunction can lead to an inability to meet these demands, even in the absence of ischemia or increased intracranial pressure. Cerebral microdialysis provides the ability to accurately measure local concentrations of various solutes including lactate, pyruvate, glycerol and glucose. Experimental and clinical data demonstrate that such …

Metabolic Foundations Of Exercise-Induced Cardiac Growth., Kyle Fulghum

Electronic Theses and Dissertations

Regular aerobic exercise promotes physiological cardiac growth, which is an adaptive response thought to enable the heart to meet higher physical demands. Cardiac growth involves coordination of catabolic and anabolic activities to support ATP generation, macromolecule biosynthesis, and myocyte hypertrophy. Although previous studies suggest that exercise-induced reductions in cardiac glycolysis are critical for physiological myocyte hypertrophy, it remains unclear how exercise influences the many interlinked pathways of metabolism that support adaptive remodeling of the heart. In this thesis project, we tested the general hypothesis that aerobic exercise promotes physiological cardiac growth by coordinating myocardial metabolism to promote glucose-supported anabolic pathway …

Haploinsufficiency Of Cyp8b1 Associates With Increased Insulin Sensitivity In Humans, Shiqi Zhong, Raphael Chèvre, David Castaño Mayan, Maria Corlianò, Blake J Cochran, Kai Ping Sem, Theo H Van Dijk, Jianhe Peng, Liang Juin Tan, Siddesh V Hartimath, Boominathan Ramasamy, Peter Cheng, Albert K Groen, Folkert Kuipers, Julian L Goggi, Chester Drum, Rob M Van Dam, Ru San Tan, Kerry-Anne Rye, Michael R Hayden, Ching-Yu Cheng, Shaji Chacko, Jason Flannick, Xueling Sim, Hong Chang Tan, Roshni R Singaraja

Children’s Nutrition Research Center Staff Publications

BACKGROUND

Cytochrome P450 family 8 subfamily B member 1 (CYP8B1) generates 12α-hydroxylated bile acids (BAs) that are associated with insulin resistance in humans.

METHODS

To determine whether reduced CYP8B1 activity improves insulin sensitivity, we sequenced CYP8B1 in individuals without diabetes and identified carriers of complete loss-of-function (CLOF) mutations utilizing functional assays.

RESULTS

Mutation carriers had lower plasma 12α-hydroxylated/non–12α-hydroxylated BA and cholic acid (CA)/chenodeoxycholic acid (CDCA) ratios compared with age-, sex-, and BMI-matched controls. During insulin clamps, hepatic glucose production was suppressed to a similar magnitude by insulin, but glucose infusion rates to maintain euglycemia were higher in mutation carriers, indicating …

An Integrated Proteomic And Glycoproteomic Investigation Reveals Alterations In The N-Glycoproteomic Network Induced By 2-Deoxy-D-Glucose In Colorectal Cancer Cells, Cheng Ma, Hong-Yuan Tsai, Qi Zhang, Lakmini Senavirathna, Lian Li, Lih-Shen Chin, Ru Chen, Sheng Pan

Faculty, Staff and Students Publications

As a well-known glycolysis inhibitor for anticancer treatment, 2-Deoxy-D-glucose (2DG) inhibits the growth and survival of cancer cells by interfering with the ATP produced by the metabolism of D-glucose. In addition, 2DG inhibits protein glycosylation in vivo by competing with D-mannose, leading to endoplasmic reticulum (ER) stress and unfolded protein responses in cancer cells. However, the molecular details underlying the impact of 2DG on protein glycosylation remain largely elusive. With an integrated approach to glycoproteomics and proteomics, we characterized the 2DG-induced alterations in N-glycosylation, as well as the cascading impacts on the whole proteome using the HT29 colorectal cancer …

French-Fried Potato Consumption And Energy Balance: A Randomized Controlled Trial, Daniel L Smith, Rebecca L Hanson, Stephanie L Dickinson, Xiwei Chen, Amy M Goss, John B Cleek, W Timothy Garvey, David B Allison

Children’s Nutrition Research Center Staff Publications

Background: Epidemiologic observations suggest increased potato consumption correlates with weight gain, adiposity, and diabetes risk, whereas nut consumption is associated with weight control and metabolic health. Randomized controlled trial (RCT) data indicate humans respond to changes in energy intake in single dietary components and compensate for extra energy consumed.

Objectives: We completed an RCT testing whether increased daily potato consumption influences energy balance [specifically, fat mass (FM)] compared with calorie-matched almond consumption.

Methods: A 30-d RCT of 180 adults prescribed calorie-matched (300 kcal/d, n = 60 participants/group) than consumed 1 of the following: 1) almonds (almond group), 2) French fries …

Fibroblast Growth Factor 15/19 Expression, Regulation, And Function: An Overview, Greg Guthrie, Caitlin Vonderohe, Douglas Burrin

Children’s Nutrition Research Center Staff Publications

Since the discovery of fibroblast growth factor (FGF)-19 over 20 years ago, our understanding of the peptide and its role in human biology has moved forward significantly. A member of a superfamily of paracrine growth factors regulating embryonic development, FGF19 is unique in that it is a dietary-responsive endocrine hormone linked with bile acid homeostasis, glucose and lipid metabolism, energy expenditure, and protein synthesis during the fed to fasted state. FGF19 achieves this through targeting multiple tissues and signaling pathways within those tissues. The diverse functional capabilities of FGF19 is due to the unique structural characteristics of the protein and …

Protein Tyrosine Phosphatase Receptor Δ Serves As The Orexigenic Asprosin Receptor, Ila Mishra, Wei Rose Xie, Juan C Bournat, Yang He, Chunmei Wang, Elizabeth Sabath Silva, Hailan Liu, Zhiqiang Ku, Yinghua Chen, Bernadette O Erokwu, Peilin Jia, Zhongming Zhao, Zhiqiang An, Chris A Flask, Yanlin He, Yong Xu, Atul R Chopra

Faculty, Staff and Student Publications

Asprosin is a fasting-induced glucogenic and centrally acting orexigenic hormone. The olfactory receptor Olfr734 is known to be the hepatic receptor for asprosin that mediates its effects on glucose production, but the receptor for asprosin's orexigenic function has been unclear. Here, we have identified protein tyrosine phosphatase receptor δ (Ptprd) as the orexigenic receptor for asprosin. Asprosin functions as a high-affinity Ptprd ligand in hypothalamic AgRP neurons, regulating the activity of this circuit in a cell-autonomous manner. Genetic ablation of Ptprd results in a strong loss of appetite, leanness, and an inability to respond to the orexigenic effects of asprosin. …

Examining 24-Hour Activity And Sleep Behaviors And Related Determinants In Latino Adolescents And Young Adults With Obesity, Erica G Soltero, Neeku Navabi, Kiley B Vander Wyst, Edith Hernandez, Felipe G Castro, Stephanie L Ayers, Jenny Mendez, Gabriel Q Shaibi

Children’s Nutrition Research Center Staff Publications

Background.

Few studies have examined 24-hour activity and sleep behaviors and their contribution to type 2 diabetes (T2D) in Latino adolescents and young adults with obesity.

Aim.

This study included quantitative data on T2D risk and 24-hour activity and sleep behaviors and qualitative data on individual, social, and environmental behavioral determinants.

Method.

A 7 day, 24-hour, wrist-worn accelerometer protocol assessed moderate-to-vigorous physical activity (PA), sedentary behaviors (SB), sleep, and sleep regularity, in adolescents (N = 38; 12–16 years) and young adults (N = 22; 18–22 years). T2D-related outcomes included adiposity (BMI, BF%, waist circumference), fasting, and 2-hour glucose. …

Gabra5 Plays A Sexually Dimorphic Role In Pomc Neuron Activity And Glucose Balance, Zhou Pei, Yang He, Jonathan C Bean, Yongjie Yang, Hailan Liu, Meng Yu, Kaifan Yu, Ilirjana Hyseni, Xing Cai, Hesong Liu, Na Qu, Longlong Tu, Kristine M Conde, Mengjie Wang, Yongxiang Li, Na Yin, Nan Zhang, Junying Han, Camille Hs Potts, Nikolas A Scarcelli, Zili Yan, Pingwen Xu, Qi Wu, Yanlin He, Yong Xu, Chunmei Wang

Children’s Nutrition Research Center Staff Publications

Pro-opiomelanocortin (POMC) neurons are important for the regulation of body weight and glucose balance. The inhibitory tone to POMC neurons is mediated primarily by the GABA receptors. However, the detailed mechanisms and functions of GABA receptors are not well understood. The α5 subunit of GABAA receptor, Gabra5, is reported to regulate feeding, and we found that Gabra5 is highly expressed in POMC neurons. To explore the function of Gabra5 in POMC neurons, we knocked down Gabra5 specifically from mature hypothalamic POMC neurons using the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 strategy. This POMC-specific knock-down of Gabra5 did not affect …

Endothelium-Specific Depletion Of Lrp1 Improves Glucose Homeostasis Through Inducing Osteocalcin, Hua Mao, Luge Li, Qiying Fan, Aude Angelini, Pradip K Saha, Cristian Coarfa, Kimal Rajapakshe, Dimuthu Perera, Jizhong Cheng, Huaizhu Wu, Christie M Ballantyne, Zheng Sun, Liang Xie, Xinchun Pi

Faculty, Staff and Students Publications

The vascular endothelium is present within metabolic organs and actively regulates energy metabolism. Here we show osteocalcin, recognized as a bone-secreted metabolic hormone, is expressed in mouse primary endothelial cells isolated from heart, lung and liver. In human osteocalcin promoter-driven green fluorescent protein transgenic mice, green fluorescent protein signals are enriched in endothelial cells lining aorta, small vessels and capillaries and abundant in aorta, skeletal muscle and eye of adult mice. The depletion of lipoprotein receptor-related protein 1 induces osteocalcin through a Forkhead box O -dependent pathway in endothelial cells. Whereas depletion of osteocalcin abolishes the glucose-lowering effect of low-density …

Adipose Tissue Hyaluronan Production Improves Systemic Glucose Homeostasis And Primes Adipocytes For Cl 316,243-Stimulated Lipolysis, Yi Zhu, Na Li, Mingyang Huang, Mason Bartels, Sophie Dogné, Shangang Zhao, Xi Chen, Clair Crewe, Leon Straub, Lavanya Vishvanath, Zhuzhen Zhang, Mengle Shao, Yongjie Yang, Christy M Gliniak, Ruth Gordillo, Gordon I Smith, William L Holland, Rana K Gupta, Bingning Dong, Nathalie Caron, Yong Xu, Yucel Akgul, Samuel Klein, Philipp E Scherer

Faculty, Staff and Students Publications

Plasma hyaluronan (HA) increases systemically in type 2 diabetes (T2D) and the HA synthesis inhibitor, 4-Methylumbelliferone, has been proposed to treat the disease. However, HA is also implicated in normal physiology. Therefore, we generated a Hyaluronan Synthase 2 transgenic mouse line, driven by a tet-response element promoter to understand the role of HA in systemic metabolism. To our surprise, adipocyte-specific overproduction of HA leads to smaller adipocytes and protects mice from high-fat-high-sucrose-diet-induced obesity and glucose intolerance. Adipocytes also have more free glycerol that can be released upon beta3 adrenergic stimulation. Improvements in glucose tolerance were not linked to increased plasma …

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 …

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 …