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Energy Metabolism: The chemical reactions involved in the production and utilization of various forms of energy in cells.

What is Metabolism?

JoVE 10725

Metabolism represents all of the chemical activity in a cell, including reactions that build molecules (anabolism) and those that break molecules down (catabolism). Anabolic reactions require energy, whereas catabolic reactions provide it. Thus, metabolism describes how cells transform energy through a variety of chemical reactions, which are often made more efficient with the help of enzymes. Metabolism is the management of energy in cells and provides three key functions: converting food into energy to run various cellular processes, producing energy to build cell components, and removing waste products. To produce energy, macromolecules from food must be broken down into smaller molecules—through a catabolic pathway. This, in turn, provides energy to construct larger molecules from smaller building blocks—through an anabolic pathway. In other words, the potential energy in food—comprised of the chemical energy stored in the bonds between atoms—can be converted into kinetic energy that can be used for cellular reactions. Enzymes are essential molecular tools in metabolic pathways, as they greatly speed up many chemical reactions by reducing the amount of required energy. Catabolism is the breakdown of macromolecules for any purpose. This inc

 Core: Metabolism

Energy-requiring Steps of Glycolysis

JoVE 10738

Glucose is the source of nearly all energy used by organisms. The first step of converting glucose into usable energy is called glycolysis. Glycolysis occurs in the cytosol of the cell over two phases: an energy-requiring phase and an energy-releasing phase. Over the first three steps, glucose is converted into different forms and attaches to two phosphate groups donated by two ATP molecules, resulting in an unstable sugar. In the next two stages, the unstable sugar splits into two sugar isomers which are either converted or used directly in the next phase of glycolysis. First, glucose receives a phosphate group from ATP converting it into a more reactive form (glucose 6-phosphate). Because glucose attached to the negatively-charged phosphate cannot cross the hydrophobic cell membrane, the addition of a phosphate group also traps glucose inside the cell. Next, the more reactive form of glucose is converted into one of its isomers, fructose 6-phosphate, which is required for subsequent energy-requiring steps of glycolysis. Fructose 6-phosphate then receives a phosphate group from a second ATP molecule. This converts fructose 6-phosphate into fructose 1,6-bisphosphate, an unstable sugar. This unstable sugar splits into two distinct three-carbon sugar isomers, glyceraldehyde 3-phosphate and DHAP. Glyceraldehyde 3-phosphate can be directly use

 Core: Cellular Respiration

What are Carbohydrates?

JoVE 10680

Carbohydrates are essential biological molecules made of carbon, hydrogen, and oxygen atoms, often in the ratio of 1:2:1. They occur as simple or complex structures and are essential for energy metabolism and storage.

All carbohydrates are sugars, also called saccharides. However, depending on their length and complexity carbohydrates can be classified as monosaccharides, disaccharides, and polysaccharides. Monosaccharides are also called simple sugars. Polysaccharides are referred to as complex carbohydrates. They are polymers, as they are built from repeating units of simple sugars. One of the simplest sugars is glucose. It is made of six carbons, 12 hydrogens, and six oxygens (i.e., C6H12O6). Glucose has a single sugar unit and is, therefore, a monosaccharide. Even such a simple molecule has several variants (isomers), depending on the orientation of individual atoms in space. For instance, if the hydroxyl (-OH) group on carbon number five points to the right, we speak of D-Glucose, if it points to the left, it is L-Glucose. The two molecules are enantiomers, mirror images of each other. The representation of a molecule as a ring structure is called Haworth projection. It reveals another option to arrange the atoms in a glucose molecule. Identify the carbon that previously carried the carboxyl group (

 Core: Macromolecules

The Use of Magnetic Resonance Spectroscopy as a Tool for the Measurement of Bi-hemispheric Transcranial Electric Stimulation Effects on Primary Motor Cortex Metabolism

1Department of Psychology, University of Montréal, 2Montreal Neurological Institute, McGill University, 3Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota

JoVE 51631

 Neuroscience

Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging

1Department of Nuclear Medicine, Klinikum rechts der Isar, Technische Universität München, 2Department of Chemistry, Technische Universität München, 3GE Global Research, 4Zentralinstitut für Medizintechnik der Technischen Universität München (IMETUM), Technische Universität München, 5Institute for Biological and Medical Imaging (IBMI), Helmholtz Zentrum München, 6IDG Institute of Developmental Genetics, Helmholtz Zentrum München

JoVE 54751

 Cancer Research

A Fluorescence-based Assay for Characterization and Quantification of Lipid Droplet Formation in Human Intestinal Organoids

1Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht University, 2Regenerative Medicine Center, University Medical Center Utrecht, Utrecht University, 3Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University

JoVE 60150

 Medicine

Monitoring Astrocyte Reactivity and Proliferation in Vitro Under Ischemic-Like Conditions

1Department of Neuroscience, School of Medicine, Universidad Central del Caribe, 2Department of Biochemistry, School of Medicine, Universidad Central del Caribe, 3Department of Pharmacology and Toxicology, Medical Sciences, Campus, University of Puerto Rico

JoVE 55108

 Neuroscience

Whole Body and Regional Quantification of Active Human Brown Adipose Tissue Using 18F-FDG PET/CT

1Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 2National Cancer Institute, National Institutes of Health, 3Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School

JoVE 58469

 Medicine

Preparation of Mitochondria from Ovarian Cancer Tissues and Control Ovarian Tissues for Quantitative Proteomics Analysis

1Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, 2Hunan Engineering Laboratory for Structural Biology and Drug Design, Xiangya Hospital, Central South University, 3State Local Joint Engineering Laboratory for Anticancer Drugs, Xiangya Hospital, Central South University, 4National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, 5Department of Obstetrics and Gynecology, Xiangya Hospital, Central South University

Video Coming Soon

JoVE 60435

 JoVE In-Press

Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice

1University of Ottawa Heart Institute, 2Department of Cellular and Molecular Medicine, University of Ottawa, 3Translational Medicine Program, The Hospital for Sick Children, 4Department of Laboratory Medicine and Pathobiology, University of Toronto, 5Banting and Best Diabetes Centre, University of Toronto

Video Coming Soon

JoVE 60174

 JoVE In-Press

Purification of Extracellular Trypanosomes, Including African, from Blood by Anion-Exchangers (Diethylaminoethyl-cellulose Columns)

1Univ. Bordeaux UMR INTERTRYP 177 IRD CIRAD, 2IRD UMR 177 INTERTRYP CIRAD, 3CNRS, UMR 5234, Microbiologie Fondamentale et Pathogénicité, Univ. Bordeaux, 4Centre Hospitalier Université Bordeaux

JoVE 58415

 Immunology and Infection

Measuring and Interpreting Oxygen Consumption Rates in Whole Fly Head Segments

1Munich Center of Integrated Protein Science and Biomedical Center, Ludwig-Maximilians University of Munich, 2Laboratory for Metabolism and Epigenetics in Aging, Leibniz Institute for Farm Animal Biology (FBN), 3German Mouse Clinic, Helmholtz Zentrum Munich, German Research Center for Environment and Health (GmbH), 4German Center for Diabetes Research (DZD), 5Chair of Experimental Genetics, School of Life Science Weihenstephan, Technische Universität München, 6Laboratory for Metabolism and Epigenetics in Brain Aging, Institute of Neuroregeneration & Neurorehabilitation of Qingdao University, 7Molecular Biology Division, Biomedical Center, Faculty of Medicine, Ludwig-Maximilians University of Munich

JoVE 58601

 Biochemistry

Measurement of Energy Metabolism in Explanted Retinal Tissue Using Extracellular Flux Analysis

1Division of Metabolism, Endocrinology and Lipid Research, Department of Medicine, Washington University School of Medicine, 2Department of Biomedical Engineering, Washington University in Saint Louis, 3Department of Ophthalmology and Visual Science, Washington University School of Medicine

JoVE 58626

 Biology

Isolation of Primary Mouse Hepatocytes for Nascent Protein Synthesis Analysis by Non-radioactive L-azidohomoalanine Labeling Method

1Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, 2Division of Endocrinology, Cincinnati Children's Hospital Medical Center, 3Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 4Department of Pediatrics, College of Medicine, University of Cincinnati

JoVE 58323

 Medicine

New Application of an Atmospheric Pressure Plasma Jet as a Neuro-protective Agent Against Glucose Deprivation-induced Injury of SH-SY5Y Cells

1Department of Pathophysiology, Beijing Neurosurgical Institute/Beijing Tiantan Hospital, Capital Medical University, 2School of Physics, Beijing Institute of Technology, 3Beijing Key Laboratory of Central Nervous System Injury, Beijing Neurosurgical Institute, Beijing Tiantan Hospital, Capital Medical University, 4Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing Tiantan Hospital, Capital Medical University, 5China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University

JoVE 56323

 Engineering
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