Biochemical Phenomena, Metabolism, and Nutrition Commons^™

The Hypothalamus For Whole-Body Physiology: From Metabolism To Aging, Tiemin Liu, Yong Xu, Chun-Xia Yi, Qingchun Tong, Dongsheng Cai

Children’s Nutrition Research Center Staff Publications

Obesity and aging are two important epidemic factors for metabolic syndrome and many other health issues, which contribute to devastating diseases such as cardiovascular diseases, stroke and cancers. The brain plays a central role in controlling metabolic physiology in that it integrates information from other metabolic organs, sends regulatory projections and orchestrates the whole-body function. Emerging studies suggest that brain dysfunction in sensing various internal cues or processing external cues may have profound effects on metabolic and other physiological functions. This review highlights brain dysfunction linked to genetic mutations, sex, brain inflammation, microbiota, stress as causes for whole-body pathophysiology, arguing …

Characterizing The Roles Of Cannabinoid Receptor 1 & 2 In Zebrafish Behavior, Metabolism, And Seizure-Induced Activity, Kayci Kimmons

Honors Theses

Epileptic disorders like Dravet Syndrome require novel studies to determine the most ideal treatment. New research linking the endocannabinoid system (ECS) to epileptic disorders is arising, but there is still much to be discovered about the function and regulatory impact of the endocannabinoid system and its receptors in epilepsies like Dravet. In this study, knockout models of larval and adult zebrafish (Danio rerio) were used to investigate the roles of cannabinoid receptors 1 & 2 in behavior, brain mitochondrial metabolism, and seizure-induced activity following exposure to THC and CBD. Larval zebrafish which lacked cannabinoid receptor 1 exhibited increased …

Severe Hypoxia Up-Regulates Gluconeogenesis In Daphnia, Morad C. Malek

Undergraduate Honors Theses

Hypoxia is a significant low oxygen state that has complex and diverse impacts on organisms. In aerobes, various adaptive responses to hypoxia are observed that vary depending on the level of oxygen depletion and previous adaptation, hence the continued attention to hypoxia as an important abiotic stressor. Adaptive responses to hypoxia are primarily governed by the hypoxia-inducible factors (HIFs), which activate downstream genetic pathways responsible for oxygen transport and metabolic plasticity. In aquatic habitats, oxygen availability can vary greatly over time and space. Therefore, aquatic organisms’ adaptation to hypoxia is likely pervasive, especially in genotypes originating from waterbodies prone to …

Targeting Metabolic Adaptations To Anti-Angiogenic Therapy In Ovarian Cancer, Deanna M. Glassman, Deanna Glassman

Dissertations and Theses (Open Access)

ABSTRACT

Background: Ovarian cancer is the most lethal gynecologic malignancy. Despite modest clinical improvements with anti-VEGF antibody (AVA) therapy, adaptive resistance is nearly ubiquitous and additional therapeutic options are limited. A dependence on glutamine metabolism, via the enzyme glutaminase (GLS), is a known mechanism of adaptive resistance.

Purpose: To assess the efficacy of a glutaminase inhibitor as a means of exploiting the metabolic vulnerability of glutamine dependence that develops as a result of adaptive resistance to AVA therapy.

Experimental Design: We used a glutaminase inhibitor (GLSi) synthesized at MD Anderson Cancer Center for all in vitro and in vivo experiments. …

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. …

Deletion Of Period Genes Exacerbates Diet-Induced Obesity In Female, But Not Male, Mice, Elizabeth Kantra

Theses and Dissertations--Biology

Sex differences in obesity in mice are mediated by differential responses of circadian rhythms to high-fat feeding in males and females. Other studies also showed circadian Period genes regulate diet-induced obesity in mice. In this study, we investigated the role of the Period genes in regulating sex differences in obesity. Male and female C57BL/6J wild type, Per1/2 KO, and Per1/2/3 KO mice were housed in 12L:12D and fed high-fat diet for 12 weeks. We found a striking sex difference in obesity such that disabling the Period genes exacerbated adiposity in female, but not male, mice. Increased adiposity in female Period …

A Cancer Ubiquitome Landscape Identifies Metabolic Reprogramming As Target Of Parkin Tumor Suppression, Ekta Agarwal, Aaron R Goldman, Hsin-Yao Tang, Andrew V Kossenkov, Jagadish C Ghosh, Lucia Languino, Valentina Vaira, David W Speicher, Dario C Altieri

Department of Cancer Biology Faculty Papers

Changes in metabolism that affect mitochondrial and glycolytic networks are hallmarks of cancer, but their impact in disease is still elusive. Using global proteomics and ubiquitome screens, we now show that Parkin, an E3 ubiquitin ligase and key effector of mitophagy altered in Parkinson's disease, shuts off mitochondrial dynamics and inhibits the non-oxidative phase of the pentose phosphate pathway. This blocks tumor cell movements, creates metabolic and oxidative stress, and inhibits primary and metastatic tumor growth. Uniformly down-regulated in cancer patients, Parkin tumor suppression requires its E3 ligase function, is reversed by antioxidants, and is independent of mitophagy. These data …

Deciphering An Agrp-Serotoninergic Neural Circuit In Distinct Control Of Energy Metabolism From Feeding, Yong Han, Guobin Xia, Dollada Srisai, Fantao Meng, Yanlin He, Yali Ran, Yang He, Monica Farias, Giang Hoang, István Tóth, Marcelo O Dietrich, Miao-Hsueh Chen, Yong Xu, Qi Wu

Children’s Nutrition Research Center Staff Publications

Contrasting to the established role of the hypothalamic agouti-related protein (AgRP) neurons in feeding regulation, the neural circuit and signaling mechanisms by which they control energy expenditure remains unclear. Here, we report that energy expenditure is regulated by a subgroup of AgRP neurons that send non-collateral projections to neurons within the dorsal lateral part of dorsal raphe nucleus (dlDRN) expressing the melanocortin 4 receptor (MC4R), which in turn innervate nearby serotonergic (5-HT) neurons. Genetic manipulations reveal a bi-directional control of energy expenditure by this circuit without affecting food intake. Fiber photometry and electrophysiological results indicate that the thermo-sensing MC4RdlDRN neurons …

Sirt3 Is Required For Liver Regeneration But Not For The Beneficial Effect Of Nicotinamide Riboside, Sarmistha Mukherjee, James Mo, Lauren M Paolella, Caroline E Perry, Jade Toth, Mindy M Hugo, Qingwei Chu, Qiang Tong, Karthikeyani Chellappa, Joseph A Baur

Children’s Nutrition Research Center Staff Publications

Liver regeneration is critical to survival after traumatic injuries, exposure to hepatotoxins, or surgical interventions, yet the underlying signaling and metabolic pathways remain unclear. In this study, we show that hepatocyte-specific loss of the mitochondrial deacetylase SIRT3 drastically impairs regeneration and worsens mitochondrial function after partial hepatectomy. Sirtuins, including SIRT3, require NAD as a cosubstrate. We previously showed that the NAD precursor nicotinamide riboside (NR) promotes liver regeneration, but whether this involves sirtuins has not been tested. Here, we show that despite their NAD dependence and critical roles in regeneration, neither SIRT3 nor its nuclear counterpart SIRT1 is required for …

Associations Between Lipoprotein Subfractions And Area And Density Of Abdominal Muscle And Intermuscular Adipose Tissue: The Multi-Ethnic Study Of Atherosclerosis, Megan M Marron, Matthew Allison, Alka M Kanaya, Britta Larsen, Alexis C Wood, David Herrington, Philip Greenland, Iva Miljkovic

Children’s Nutrition Research Center Staff Publications

Skeletal muscle quantity and quality decrease with older age, which is partly attributed to ectopic fat infiltration and has negative metabolic consequences. To inform efforts to preserve skeletal muscle with aging, a better understanding of biologic correlates of quantity and quality of muscle and intermuscular adipose tissue (IMAT) is needed. We used targeted lipidomics of lipoprotein subfractions among 947 Multi-Ethnic Study of Atherosclerosis participants to provide a detailed metabolic characterization of area and density of abdominal muscle and IMAT. Serum lipoprotein subfractions were measured at the first visit using 1H-Nuclear Magnetic Resonance spectroscopy. Muscle and IMAT area (cm

Therapeutic Potential Of A Ketogenic Diet In The Treatment Of Major Depressive Disorder, Jordan A. Murrin

Masters Theses, 2020-current

Major depressive disorder (MDD) is the second most common mental health condition and a leading cause of disability in the world. It is theorized that MDD develops from a combination of biological, psychological, and social stressors. The condition is typically treated using pharmaceuticals and psychotherapy. However, not all individuals with MDD have access to or choose to use these treatments, or may prefer to incorporate therapeutic lifestyle changes such as exercise, sleep, and healthy eating. Even with treatment, MDD can alter brain structure and function, leading to the development of comorbid mental health and chronic metabolic conditions like obesity, cardiovascular …

Disrupted Hypothalamic Crh Neuron Responsiveness Contributes To Diet-Induced Obesity, Canjun Zhu, Yuanzhong Xu, Zhiying Jiang, Jin Bin Tian, Ryan M Cassidy, Zhao-Lin Cai, Gang Shu, Yong Xu, Mingshan Xue, Benjamin R Arenkiel, Qingyan Jiang, Qingchun Tong

Children’s Nutrition Research Center Staff Publications

The current obesity epidemic mainly results from high-fat high-caloric diet (HFD) feeding and may also be contributed by chronic stress; however, the neural basis underlying stress-related diet-induced obesity remains unknown. Corticotropin-releasing hormone (CRH) neurons in the paraventricular hypothalamus (PVH), a known body weight-regulating region, represent one key group of stress-responsive neurons. Here, we found that HFD feeding blunted PVH CRH neuron response to nutritional challenges as well as stress stimuli and dexamethesone, which normally produce rapid activation and inhibition on these neurons, respectively. We generated mouse models with the activity of these neurons clamped at high or low levels, both …

Visualizing Metabolic Network Dynamics Through Time-Series Metabolomic Data., Lea F Buchweitz, James T Yurkovich, Christoph Blessing, Veronika Kohler, Fabian Schwarzkopf, Zachary A King, Laurence Yang, Freyr Jóhannsson, Ólafur E Sigurjónsson, Óttar Rolfsson, Julian Heinrich, Andreas Dräger

Articles, Abstracts, and Reports

BACKGROUND: New technologies have given rise to an abundance of -omics data, particularly metabolomic data. The scale of these data introduces new challenges for the interpretation and extraction of knowledge, requiring the development of innovative computational visualization methodologies. Here, we present GEM-Vis, an original method for the visualization of time-course metabolomic data within the context of metabolic network maps. We demonstrate the utility of the GEM-Vis method by examining previously published data for two cellular systems-the human platelet and erythrocyte under cold storage for use in transfusion medicine.

RESULTS: The results comprise two animated videos that allow for new insights …

Apoe As A Metabolic Regulator In Humans, Mice, And Astrocytes, Brandon C. Farmer

Theses and Dissertations--Physiology

Altered metabolic pathways appear to play central roles in the pathophysiology of late-onset Alzheimer’s disease (AD). Carrier status of the E4 allele of the APOE gene is the strongest genetic risk factor for late-onset AD, and increasing evidence suggests that E4 carriers may be at an increased risk for neurodegeneration based on inherent metabolic impairments. A new appreciation is forming for the role of APOE in cerebral metabolism, and how nutritional factors may impact this role. In chapter 1, the literature on nutritional interventions in E4 carriers aimed at mitigating disease risk is reviewed. Studies investigating the mechanism by which …

Mitochondrial Metabolism In Major Neurological Diseases, Zhengqiu Zhou, Grant L. Austin, Lyndsay E. A. Young, Lance A. Johnson, Ramon Sun

Molecular and Cellular Biochemistry Faculty Publications

Mitochondria are bilayer sub-cellular organelles that are an integral part of normal cellular physiology. They are responsible for producing the majority of a cell’s ATP, thus supplying energy for a variety of key cellular processes, especially in the brain. Although energy production is a key aspect of mitochondrial metabolism, its role extends far beyond energy production to cell signaling and epigenetic regulation–functions that contribute to cellular proliferation, differentiation, apoptosis, migration, and autophagy. Recent research on neurological disorders suggest a major metabolic component in disease pathophysiology, and mitochondria have been shown to be in the center of metabolic dysregulation and possibly …

Mitochondrial Reactive Oxygen Species In Lipotoxic Hearts Induces Post-Translational Modifications Of Akap121, Drp1 And Opa1 That Promote Mitochondrial Fission, Kensuke Tsushima, Heiko Bugger, Adam R. Wende, Jamie Soto, Gregory A. Jenson, Austin R. Tor, Rose Mcglauflin, Helena C. Kenny, Yuan Zhang, Rhonda Souvenir, Xiao X. Hu, Crystal L. Sloan, Renata O. Pereira, Vitor A. Lira, Kenneth W. Spitzer, Terry L. Sharp, Kooresh I. Shoghi, Genevieve C. Sparagna, Eva A. Rog-Zielinska, Peter Kohl, Oleh Khalimonchuk, Jean E. Schaffer, E. Dale Abel

Department of Biochemistry: Faculty Publications

Rationale: Cardiac lipotoxicity, characterized by increased uptake, oxidation and accumulation of lipid intermediates, contributes to cardiac dysfunction in obesity and diabetes. However, mechanisms linking lipid overload and mitochondrial dysfunction are incompletely understood.

Objective: To elucidate the mechanisms for mitochondrial adaptations to lipid overload in postnatal hearts in vivo.

Methods and Results: Using a transgenic mouse model of cardiac lipotoxicity overexpressing long-chain acyl-CoA synthetase 1 in cardiomyocytes, we show that modestly increased myocardial fatty acid uptake leads to mitochondrial structural remodeling with significant reduction in minimum diameter. This is associated with increased palmitoyl-carnitine oxidation and increased reactive oxygen species (ROS) generation …

Exploring Cancer Metabolism Using Stable Isotope-Resolved Metabolomics (Sirm), Ronald C. Bruntz, Andrew N. Lane, Richard M. Higashi, Teresa W. -M. Fan

Center for Environmental and Systems Biochemistry Faculty Publications

Metabolic reprogramming is a hallmark of cancer. The changes in metabolism are adaptive to permit proliferation, survival, and eventually metastasis in a harsh environment. Stable isotope-resolved metabolomics (SIRM) is an approach that uses advanced approaches of NMR and mass spectrometry to analyze the fate of individual atoms from stable isotope-enriched precursors to products to deduce metabolic pathways and networks. The approach can be applied to a wide range of biological systems, including human subjects. This review focuses on the applications of SIRM to cancer metabolism and its use in understanding drug actions.

Appetite Control With Relevance To Mitochondrial Biogenesis And Activation Of Post-Prandial Lipid Metabolism In Obesity Linked Diabetes, Ian J. Martins

Research outputs 2014 to 2021

In various communities in the developing and developed world the understanding of the ingestion of a healthy diet [1] and hepatic fat metabolism has become of critical importance to the treatment of obesity linked Type 2 diabetes that is now linked to various organ diseases [2]. In the developing world transition to healthy diets has become urgent to prevent insulin resistance [3,4] and the obesity pandemic [5-8]. The liver is the major organ for the metabolism of dietary fat and after consumption of a meal in healthy individuals the fat is rapidly metabolized by the liver. In obesity linked Type …

The Metabolism Of Alcohol: Risk And Protective Factors, Sydney E. Levan, Amy Adkins, Danielle Dick, Karen G. Chartier

UROP Posters

Purpose: Abstract for poster submission to VCU Poster Symposium for

Undergraduate Research and Creativity

Title: The Metabolism of Alcohol: Risk and Protective Factors

Background: In 2002, it was reported by the National Institutes of Health that

60.3% of college aged students (18-22) drank alcohol in the past month of being

asked, as compared to 51.9% of those not in college. They also found that 20% of

college students met the criteria for at least one alcohol use disorder (AUDs)1.

Many genes have been linked to an increased risk for AUDs and how individuals

with various ethnic backgrounds respond to alcohol. …

Effects Of Prior Acute Exercise On Circulating Cytokine Concentration Responses To A High-Fat Meal, Josef Brandauer, Rian Q. Landers-Ramos, Nathan T. Jenkins, Espen E. Spangenburg, James M. Hagberg, Steven J. Prior

Health Sciences Faculty Publications

High-fat meal consumption alters the circulating cytokine profile and contributes to cardiometabolic diseases. A prior bout of exercise can ameliorate the triglyceride response to a high-fat meal, but the interactive effects of exercise and high-fat meals on cytokines that mediate cardiometabolic risk are not fully understood. We investigated the effects of prior exercise on the responses of circulating tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), IL-8, leptin, retinol-binding protein 4 (RBP4), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1) to a high-fat meal. Ten healthy men were studied before …

Nerve, Muscle, Blood, Toil, Tears, And Sweat: England’S Pioneering Biophysicist, Soldier, And Statesman, Arshad Khan

Selected Works Temporary Series

No abstract provided.

Nerve, Muscle, Blood, Toil, Tears, And Sweat: England’S Pioneering Biophysicist, Soldier, And Statesman, Khan

Departmental Papers (Biology)

No abstract provided.

Role For Akt3/Protein Kinase Bγ In Attainment Of Normal Brain Size, Rachel M. Easton, Han Cho, Kristin Roovers, Diana W. Shineman

Dartmouth Scholarship

Studies of Drosophila and mammals have revealed the importance of insulin signaling through phosphatidylinositol 3-kinase and the serine/threonine kinase Akt/protein kinase B for the regulation of cell, organ, and organismal growth. In mammals, three highly conserved proteins, Akt1, Akt2, and Akt3, comprise the Akt family, of which the first two are required for normal growth and metabolism, respectively. Here we address the function of Akt3. Like Akt1, Akt3 is not required for the maintenance of normal carbohydrate metabolism but is essential for the attainment of normal organ size. However, in contrast to Akt1^−/− mice, which display a …