Insights Into the Hexose Liver Metabolism—Glucose Versus Fructose
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Fructose Metabolism from a Functional
SSE #174 Sports Science Exchange (2017) Vol. 28, No. 174, 1-5 FRUCTOSE METABOLISM FROM A FUNCTIONAL PERSPECTIVE: IMPLICATIONS FOR ATHLETES Luke Tappy, MD | Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Service of Endocrinology, Diabetes and Metabolism | Lausanne University Hospital, and Cardio-metabolic Center, Broye Hospital | Estavayer-le-lac, Switzerland • Fructose was originally a seasonal natural nutrient, mainly consumed in summer and fall in fruits and vegetables. In the industrial era, it became a permanent constituent of our diet, essentially a constituent of added sugars (sucrose, high-fructose corn syrup). • Fructose cannot be directly metabolized by most cells in our body. It has to be processed first in the gut, liver and kidneys, where it is converted into glucose, lactate and fatty acids. • Too much dietary fructose along with excess energy intake and low physical activity can cause hepatic insulin resistance, hypertriglyceridemia and increased hepatic fat content. GAT11LOGO_GSSI_vert_fc_grn • In exercising athletes, net carbohydrate oxidation increases with glucose ingestion in a dose-dependent manner until a plateau is reached at about 1g/min. The addition of fructose to glucose drinks can further increase carbohydrate oxidation. • During exercise, substantial amounts of fructose can be converted into lactate in splanchnic organs if available and released in the systemic circulation to be oxidized in contracting muscles. This “reverse fructose-lactate Cori cycle” provides additional energy substrate to muscle during exercise. • Conversion of fructose into glucose and lactate in splanchnic organs is associated with enhanced splanchnic energy expenditure, while muscle energy efficiency is minimally altered. • During recovery after exercise, glucose and fructose mutually enhance their gut absorption and their storage as glycogen in the liver. -
The Metabolism of Subcutaneous Adipose Tissue in the Immediate Postnatal Period of Human Newborns
Pediat. Res. 6: 211-218 (1972) Adipose tissue glucose metabolism /3-hydroxyacyl-CoA dehydrogenase neonates fatty acid catabolism phosphofructokinase The Metabolism of Subcutaneous Adipose Tissue in the Immediate Postnatal Period of Human Newborns. 2. Developmental Changes in the Metabolism of 14C-(U)-D-Glucose and in Enzyme Activities of Phosphofructo- kinase (PFK; EC. 2.7.1.11) and /3-Hydroxyacyl-CoA Dehydro- genase (HAD; EC. 1.1.1.35) M. NOVAK1351, E. MONKUS, H. WOLF, AND U. STAVE Department of Pediatrics, University of Miami School of Medicine, Miami, Florida, USA, Staedtische Kinderklinik, Kassel, West Germany, and Fels Research Institute, Yellow Springs, Ohio, USA Extract Changes in the in vitro metabolism of subcutaneous adipose tissue have been compared in normal human newborns from 2 hr to 2 weeks of age. A group of healthy adult volunteers was also included. Samples were obtained by using a needle biopsy tech- nique. More of the isotope from uC-(U)-D-glucose was incorporated into triglyc- erides (P < 0.05) and also oxidized by suspensions of adipose cells from infants 2-3 hr of age than in older infants (P < 0.01). The ratio of radioactivity in carbon dioxide to radioactivity in triglyceride was also significantly greater in 2- to 3-hr-old infants than in older neonates (P < 0.05). Thin layer chromatography of the total lipid ex- tract showed the greatest amount of radioactivity in the triglycerides, a small amount in 1,3-digiycerides and 1,2-diglycerides, and a trace in fatty acids and monogiyc- erides. These findings were compared with the developmental changes in two key enzymes: phosphofructokinase (PFK), which represents the glycolytic pathway, and (3-hydroxyacyl-coenzyme A (GoA) dehydrogenase (HAD), which is involved in the P oxidation of fatty acids. -
Fructose-Induced Increases in Expression of Intestinal Fructolytic and Gluconeogenic Genes Are Regulated by GLUT5 and KHK
Fructose-induced increases in expression of intestinal fructolytic and gluconeogenic genes are regulated by GLUT5 and KHK. Chirag Patel, Véronique Douard, Shiyan Yu, Phuntila Tharabenjasin, Nan Gao, Ronaldo P Ferraris To cite this version: Chirag Patel, Véronique Douard, Shiyan Yu, Phuntila Tharabenjasin, Nan Gao, et al.. Fructose- induced increases in expression of intestinal fructolytic and gluconeogenic genes are regulated by GLUT5 and KHK.. AJP - Regulatory, Integrative and Comparative Physiology, American Physio- logical Society, 2015, 309 (5), pp.R499-509. 10.1152/ajpregu.00128.2015. hal-01607831 HAL Id: hal-01607831 https://hal.archives-ouvertes.fr/hal-01607831 Submitted on 28 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Copyright Am J Physiol Regul Integr Comp Physiol 309: R499–R509, 2015. First published June 17, 2015; doi:10.1152/ajpregu.00128.2015. Fructose-induced increases in expression of intestinal fructolytic and gluconeogenic genes are regulated by GLUT5 and KHK Chirag Patel,1 Veronique Douard,1 Shiyan Yu,2 Phuntila Tharabenjasin,1 Nan Gao,2 and Ronaldo P. Ferraris1 1Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers University, Newark, New Jersey; and 2Department of Biological Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey Submitted 30 March 2015; accepted in final form 16 June 2015 Patel C, Douard V, Yu S, Tharabenjasin P, Gao N, Ferraris blood fructose is directly dependent on intestinal processing of RP. -
Chapter 12 Slides
11/15/17 CHAPTER 12: Carbohydrates: Structure and Function OUTLINE • 12.1 Role of Carbohydrates • 12.2 Monosaccharides • 12.3 Complex Carbohydrates • 12.4 Carbohydrate Catabolism • 12.5 Oligosaccharides as Cell Markers CHAPTER 12: Carbohydrates: Structure and Function WHAT ARE CARBOHYDRATES? • Glucose and its derivatives are carbohydrates: Ø Carbohydrates are simple organic molecules that have a shared basic chemical Formula: Cn(H2O)n Ø The name “carbo + hydrate” represents that Fact that they are made from CO2 and H2O by photosynthesis • About halF oF all earth’s solid carbon is Found in two polymers of glucose found in plants: Ø Starch = major energy storage molecule Ø Cellulose = major structural component oF the plant cell wall (aka. “fiber”) CHAPTER 12: Carbohydrates: Structure and Function THE SIMPLEST CARBOHYDRATES • Monosaccharides are carbohydrates that cannot be hydrolyZed into simpler carbohydrates: Ø These are the Fundamental building blocks For all other carbohydrates (oFten called “simple sugars”) Ø All have Formulas of based on the basic pattern: Cn(H2O)n • Monosaccharides have speciFic Functional groups: 1. An aldehyde OR a ketone (not both!) 2. Several (two or more) alcohol (-OH) groups 1 11/15/17 CHAPTER 12: Carbohydrates: Structure and Function STRUCTURE & NOMENCLATURE OF MONOSACCHARIDES • Monosaccharides are classiFied by two features: 1. Length of their main carbon chain (utilize standard IUPAC naming For # oF carbons) 2. Whether they contain an aldehyde or ketone group • Names always end with –ose • Two common hexoses: -
The Effect of 2-Desoxy-D-Glucose on Glycolysis and Respiration of Tumor and Normal Tissues
The Effect of 2-Desoxy-D-glucose on Glycolysis and Respiration of Tumor and Normal Tissues GLADYSE. WOODWARDANDMARIET. HUDSON (Biochemical Research Foundation, Newark, Delaware) Inhibition of metabolism by structural analogs end of each experiment. Reaction rates are expressed of metabolites is one of the newer concepts of of dry tissue/hour, and are based on the initial steady rate. chemotherapy. It seems possible that this concept The symbols, QCOJ.Qco2>an<l Q<v are used to express, re spectively, the rates of anaerobic glycolysis, aerobic glycolysis, might be applied to cancer by use of structural and respiration. The Q values as given in the tables are from analogs of glucose to inhibit the glycolysis of the single or duplicate determinations. tumor cell, since tumor tissue in contrast to most normal tissues possesses the ability to glycolyze RESULTS glucose at a high rate both anaerobically and EFFECTop 2DG ONGLYCOLYSIS aerobically (7). It was found that 2DG in the maximum concen 2-Desoxy-D-glucose (2DG) is a structural ana tration used with each tissue did not significantly log of glucose, differing from glucose only at the affect the endogenous glycolysis of any of the tis second carbon atom by the absence of one oxygen sues studied. Calculation of the degree of inhibi atom. This analog has been shown (2) to compete tion of glucose or fructose utilization, therefore, is with glucose in the yeast fermentation system and, based on the Q values from which the correspond thereby, to inhibit fermentation of glucose. In a ing blank Q value has been subtracted. -
Fatty Acid Biosynthesis
BI/CH 422/622 ANABOLISM OUTLINE: Photosynthesis Carbon Assimilation – Calvin Cycle Carbohydrate Biosynthesis in Animals Gluconeogenesis Glycogen Synthesis Pentose-Phosphate Pathway Regulation of Carbohydrate Metabolism Anaplerotic reactions Biosynthesis of Fatty Acids and Lipids Fatty Acids contrasts Diversification of fatty acids location & transport Eicosanoids Synthesis Prostaglandins and Thromboxane acetyl-CoA carboxylase Triacylglycerides fatty acid synthase ACP priming Membrane lipids 4 steps Glycerophospholipids Control of fatty acid metabolism Sphingolipids Isoprene lipids: Cholesterol ANABOLISM II: Biosynthesis of Fatty Acids & Lipids 1 ANABOLISM II: Biosynthesis of Fatty Acids & Lipids 1. Biosynthesis of fatty acids 2. Regulation of fatty acid degradation and synthesis 3. Assembly of fatty acids into triacylglycerol and phospholipids 4. Metabolism of isoprenes a. Ketone bodies and Isoprene biosynthesis b. Isoprene polymerization i. Cholesterol ii. Steroids & other molecules iii. Regulation iv. Role of cholesterol in human disease ANABOLISM II: Biosynthesis of Fatty Acids & Lipids Lipid Fat Biosynthesis Catabolism Fatty Acid Fatty Acid Degradation Synthesis Ketone body Isoprene Utilization Biosynthesis 2 Catabolism Fatty Acid Biosynthesis Anabolism • Contrast with Sugars – Lipids have have hydro-carbons not carbo-hydrates – more reduced=more energy – Long-term storage vs short-term storage – Lipids are essential for structure in ALL organisms: membrane phospholipids • Catabolism of fatty acids –produces acetyl-CoA –produces reducing -
Tricarboxylic Acid (TCA) Cycle Intermediates: Regulators of Immune Responses
life Review Tricarboxylic Acid (TCA) Cycle Intermediates: Regulators of Immune Responses Inseok Choi , Hyewon Son and Jea-Hyun Baek * School of Life Science, Handong Global University, Pohang, Gyeongbuk 37554, Korea; [email protected] (I.C.); [email protected] (H.S.) * Correspondence: [email protected]; Tel.: +82-54-260-1347 Abstract: The tricarboxylic acid cycle (TCA) is a series of chemical reactions used in aerobic organisms to generate energy via the oxidation of acetylcoenzyme A (CoA) derived from carbohydrates, fatty acids and proteins. In the eukaryotic system, the TCA cycle occurs completely in mitochondria, while the intermediates of the TCA cycle are retained inside mitochondria due to their polarity and hydrophilicity. Under cell stress conditions, mitochondria can become disrupted and release their contents, which act as danger signals in the cytosol. Of note, the TCA cycle intermediates may also leak from dysfunctioning mitochondria and regulate cellular processes. Increasing evidence shows that the metabolites of the TCA cycle are substantially involved in the regulation of immune responses. In this review, we aimed to provide a comprehensive systematic overview of the molecular mechanisms of each TCA cycle intermediate that may play key roles in regulating cellular immunity in cell stress and discuss its implication for immune activation and suppression. Keywords: Krebs cycle; tricarboxylic acid cycle; cellular immunity; immunometabolism 1. Introduction The tricarboxylic acid cycle (TCA, also known as the Krebs cycle or the citric acid Citation: Choi, I.; Son, H.; Baek, J.-H. Tricarboxylic Acid (TCA) Cycle cycle) is a series of chemical reactions used in aerobic organisms (pro- and eukaryotes) to Intermediates: Regulators of Immune generate energy via the oxidation of acetyl-coenzyme A (CoA) derived from carbohydrates, Responses. -
Fatty Acid Synthesis ANSC/NUTR 618 Lipids & Lipid Metabolism Fatty Acid Synthesis I
Handout 5 Fatty Acid Synthesis ANSC/NUTR 618 Lipids & Lipid Metabolism Fatty Acid Synthesis I. Overall concepts A. Definitions 1. De novo synthesis = synthesis from non-fatty acid precursors a. Carbohydrate precursors (glucose and lactate) 1) De novo fatty acid synthesis uses glucose absorbed from the diet rather than glucose synthesized by the liver. 2) De novo fatty acid synthesis uses lactate derived primarily from glucose metabolism in muscle and red blood cells. b. Amino acid precursors (e.g., alanine, branched-chain amino acids) 1) De novo fatty acid synthesis from amino acids is especially important during times of excess protein intake. 2) Use of amino acids for fatty acid synthesis may result in nitrogen overload (e.g., the Atkins diet). c. Short-chain organic acids (e.g., acetate, butyrate, and propionate) 1) The rumen of ruminants is a major site of short-chain fatty acid synthesis. 2) Only small amounts of acetate circulate in non-ruminants. 2. Lipogenesis = fatty acid or triacylglycerol synthesis a. From preformed fatty acids (from diet or de novo fatty acid synthesis) b. Requires source of carbon (from glucose or lactate) for glycerol backbone 3T3-L1 Preadipocytes at confluence. No lipid 3T3-L1 Adipocytes after 6 days of filling has yet occurred. differentiation. Dark spots are lipid droplets. 1 Handout 5 Fatty Acid Synthesis B. Tissue sites of de novo fatty acid biosynthesis 1. Liver. In birds, fish, humans, and rodents (approx. 50% of fatty acid biosynthesis). 2. Adipose tissue. All livestock species synthesize fatty acids in adipose tissue; rodents synthesize about 50% of their fatty acids in adipose tissue. -
Fructose and Mannose in Inborn Errors of Metabolism and Cancer
H OH metabolites OH Review Fructose and Mannose in Inborn Errors of Metabolism and Cancer Elizabeth L. Lieu †, Neil Kelekar †, Pratibha Bhalla † and Jiyeon Kim * Department of Biochemistry and Molecular Genetics, University of Illinois, Chicago, IL 60607, USA; [email protected] (E.L.L.); [email protected] (N.K.); [email protected] (P.B.) * Correspondence: [email protected] † These authors contributed equally to this work. Abstract: History suggests that tasteful properties of sugar have been domesticated as far back as 8000 BCE. With origins in New Guinea, the cultivation of sugar quickly spread over centuries of conquest and trade. The product, which quickly integrated into common foods and onto kitchen tables, is sucrose, which is made up of glucose and fructose dimers. While sugar is commonly associated with flavor, there is a myriad of biochemical properties that explain how sugars as biological molecules function in physiological contexts. Substantial research and reviews have been done on the role of glucose in disease. This review aims to describe the role of its isomers, fructose and mannose, in the context of inborn errors of metabolism and other metabolic diseases, such as cancer. While structurally similar, fructose and mannose give rise to very differing biochemical properties and understanding these differences will guide the development of more effective therapies for metabolic disease. We will discuss pathophysiology linked to perturbations in fructose and mannose metabolism, diagnostic tools, and treatment options of the diseases. Keywords: fructose and mannose; inborn errors of metabolism; cancer Citation: Lieu, E.L.; Kelekar, N.; Bhalla, P.; Kim, J. Fructose and Mannose in Inborn Errors of Metabolism and Cancer. -
Carbohydrate Metabolism I & II Central Aspects of Macronutrient
Carbohydrate Metabolism I & II - General concepts of glucose metabolism - - Glycolysis - -TCA - FScN4621W Xiaoli Chen, PhD Food Science and Nutrition University of Minnesota 1 Central Aspects of Macronutrient Metabolism Macronutrients (carbohydrate, lipid, protein) Catabolic metabolism Oxidation Metabolites (smaller molecules) Anabolic metabolism Energy (ATP) Synthesis of cellular components or energy stores Chemical Reactions Cellular Activities 2 Central Aspects of Macronutrient Metabolism High-energy compounds ◦ ATP (adenosine triphosphate) ◦ NADPH (reduced nicotinamide adenine dinucleotide phosphate) ◦ NADH (reduced nicotinamide adenine dinucleotide) ◦ FADH2 (reduced flavin adenine dinucleotide) Oxidation of macronutrients NADH NADPH FADH2 ATP and NADPH are required ATP for anabolic metabolism 3 1 Unit I General Concepts of Glucose Metabolism Metabolic pathways of glucose Glucose homeostasis Glucose transport in tissues Glucose metabolism in specific tissues 4 Overview Digestion, Absorption and Transport of Carbs ◦ Final products of digestion: ________, ________, and ________ Cellular fuels ◦ Glucose, fatty acids, ketone bodies, amino acids, other gluoconeogenic precursors (glycerol, lactate, propionate) Glucose: primary metabolic fuel in humans ◦ Provide 32% to 70% of the energy in diet of American population All tissues are able to use glucose as energy fuels ◦ Glucose has different metabolic fate in different tissues Physiological states determine glucose metabolic fate ◦ Fed/fasted – glucose is metabolized through distinct -
Beta (Β)-Oxidation of Fatty Acid and Its Associated Disorders
Vol. 5 (1), pp. 158-172, December, 2018 ©Global Science Research Journals International Journal of Clinical Biochemistry Author(s) retain the copyright of this article. http://www.globalscienceresearchjournals.org/ Review Article Beta (β)-Oxidation of Fatty Acid and its associated Disorders Satyam Prakash Assistant Professor, Dept. of Biochemistry, Janaki Medical College Teaching Hospital, Janakpur, Nepal Mobile: +977-9841603704, E-mail: [email protected] Accepted 18 December, 2018 The lipids of metabolic significance in the mammalian organisms include triacylglycerols, phospholipids and steroids, together with products of their metabolism such as long-chain fatty acids, glycerol and ketone bodies. The fatty acids which are present in the triacylglycerols in the reduced form are the most abundant source of energy and provide energy twice as much as carbohydrates and proteins. Fatty acids represent an important source of energy in periods of catabolic stress related to increased muscular activity, fasting or febrile illness, where as much as 80% of the energy for the heart, skeletal muscles and liver could be derived from them. The prime pathway for the degradation of fatty acids is mitochondrial fatty acid β-oxidation (FAO). The relationship of fat oxidation with the utilization of carbohydrate as a source of energy is complex and depends upon tissue, nutritional state, exercise, development and a variety of other influences such as infection and other pathological states. Inherited defects for most of the FAO enzymes have been identified and characterized in early infancy as acute life-threatening episodes of hypoketotic, hypoglycemic coma induced by fasting or febrile illness. Therefore, this review briefly highlights mitochondrial β-oxidation of fatty acids and associated disorders with clinical manifestations. -
Aerobic and Nitrate Respiration Routes of Carbohydrate Catabolism in Pseudomonas S Tut Zeri
AN ABSTRACT OF THE THESIS OF WILLIAM JAN SPANGLER for the Ph. D. in MICROBIOLOGY (Name) (Degree) (Major) thesis is presented Date 7 / `> /q6! Title AEROBIC AND NITRATE RESPIRATION ROUTES OF CAR- BOHYDRATE CATABOLISM IN PSEUDOMONAS STUTZERI Abstract approved ( Major professor) Pseudomonas stutzeri and other denitrifying bacteria are able to grow under anaerobic conditions, using nitrate -oxygen as the terminal hydrogen acceptor, in a manner analagous to classical aerobic respiration with free -molecular oxygen. This rather unique phenomenon is known as nitrate respiration. Nitrate respiration has been studied with respect to the nitrate reducing enzymes and carrier systems involved in the reduction sequence, but very little emphasis has been placed on the metabolic pathways which are associated with nitrate respiration. This study was carried out in an attempt to establish the metabolic pathways operative, both under aerobic con- ditions and during nitrate respiration, in order to determine whether there was any shift of pathways under conditions of nitrate respira- tion. Primary pathways were determined by the radiorespirometric method using specifically labelled glucose and gluconate. The results, based primarily on the rate of decarboxylation of the C -1 and C -4 positions of glucose, indicated the operation of the Entner- Doudoroff and pentose phosphate pathways under both aerobic condi- tions and conditions of nitrate respiration. Evolution of 14CO2 from the other labels of glucose, as well as incorporation of these labels into the cell, indicated that terminal pathways such as the tricar- boxylic acid cycle or glyoxalate cycle might also be operative under both conditions of oxygen relationship. The secondary pathways were studied using specifically labelled acetate.