GENERAL ANESTHETIC SITES ON LIGAND-GATED ION CHANNELS
W Keith
Massachusetts General Hospitalcity: Boston country: United States (us)
Grant 5P01GM058448-13 from National Institute Of General Medical Sciences
Abstract: Some 25 million patients are given general anesthesia each year in the USA using agents with very low therapeutic indices. The molecular mechanisms of general anesthesia remain unknown, hampering the design of improved agents. General anesthetics act on a superfamily of ligand-gated channels which include inhibitory anion channels gated by GABA and glycine, and excitatory cation channels gated by serotonin and acetylcholine. This PPG focuses on the ability of general anesthetics to enhance the activity of the inhibitory GABAA receptor (GABAAR) and to inhibit, and in some cases enhance, the excitatory neuronal nicotinic acetylcholine (nAcChoR) and serotonin (5HT3R) receptors. The overall hypothesis is that the various actions of general anesthetics are mediated by a number of binding sites on these receptors that their location and affinity varies with the anesthetic´s structure and the receptor´s conformation. The overall Aims of the PPG are to (i) locate the anesthetic binding sites on the GABAA, nAcChoR and 5-HT3 receptors using anesthetic photolabels, and (ii) define how their occupancy allosterically modulates receptor function using rapid perfusion patch clamp techniques. Project 1 will locate sites of etomidate, propofol and barbiturate photolabels on equilibrium states of GABAAR and nAcChoRs. Project 2 focuses on the interaction of anesthetics with receptors during gating using in parallel electrophysiological and time-resolved photolabeling. Project 3 will define in detail the kinetic mechanisms of anesthetic action on GABAARs using rapid perfusion patch clamp techniques in wild type and mutated receptors, incorporating the photolabeling results to guide mutagenesis and interpretation. A Synthetic Chemistry Core develops and supplies novel photoaffinity general anesthetics. A Protein Chemistry Core locates the sites of photoincorporation and develops homology models of receptors to guide mutagenesis work. A Protein Production Core supplies large quantities of heterologously expressed, purified and reconstituted neuronal receptors for photolabeling
Project start date: 1998-12-01
Project end date: 2014-08-31
Budget start date: 1-SEP-2011
Budget end date: 31-AUG-2012
PFA/PA: PA-07-030
5P01GM058448-13 (2011): $1837153
Sponsored Links Excellgen http://Excellgen.com
CORE D: PROTEIN PRODUCTION CORE
W Keith
Massachusetts General Hospitalcity: Boston country: United States (us)
Abstract: The Protein Production Core´s mission is to produce heterologously expressed, purified and reconstituted human neuronal receptors in the large quantities required for photolabeling and sequencing. This is a challenging resource-intensive objective best handled by a central facility. During the four years of its existence, the Core has thoroughly developed several inducible mammalian cell lines capable of expressing a number of Cys-loop ligand-gated ion channel receptors bearing accessible purification epitopes. With such cell lines the successive steps of solubilization, purification and reconstitution have been optimized. Two receptors are now in production in such cell lines, and it is proposed to developed three more. Using its Bioreactor facility, the Core is now in a position to routinely fulfill its overall specific aim of supplying Projects 1 & 2 with the milligram quantities of well characterized, purified receptors functionally reconstituted into defined lipid bilayers that are required for photolabeling studies. The specific receptors to be produced in this way are all human neuronal members of the Cys-loop superfamily. The primary focus is on the inhibitory receptors, specifically the following GABAA receptors synaptic receptors composed of subunits aip3y2L extrasynaptic receptors composed of subunits a4p36, and aipS receptors to act as controls. The representative excitatory receptors in the Cys-loop superfamily will be the neuronal nicotinic a4p2 receptor and the 5-HT3A receptor. A subsidiary goal is to support the needs of investigators involved in electrophysiological studies (Raines and Forman). They will be able to achieve efficiencies by using the Core´s resources both for the more straightfonward establishment of stable cell lines and for the development of mutants, although the primary responsibility remains with the investigator thereafter. This latter service will not detract from the Core´s main labor-intensive goal of developing stable, inducible cell lines and over- expressing human neuronal receptors for photolabeling and biochemical studies. The Core will be situated in the Mallinckrodt Pharmacology Laboratory at MGH. RELEVANCE (See instructions)
Keywords: Affinity Chromatography; Agonist; Antibody Affinity; base; Biochemical; Bioreactors; Brain; Cell Line; Core Facility; design; design and construction; Development; Epitopes; Equilibrium; experience; Gated Ion Channel; General anesthetic drugs; Goals; Human; Instruction; Laboratories; Lead; Ligands; Lipid Bilayers; Mammalian Cell; member; milligram; Minor; Mission; mutant; Mutation; Neurons; Pharmacology; Positioning Attribute; Production; programs; Proteins; receptor; reconstitution; Research Personnel; Resources; Services; Site; stable cell line; Synaptic Receptors; Techniques; Terminology; Tetanus Helper Peptide; Time
Budget start date: 1-SEP-2011
Budget end date: 31-AUG-2012
5P01GM058448-13_6854 (2011): $373748
CORE B: SYNTHETIC CHEMISTRY CORE
W Keith
Massachusetts General Hospitalcity: Boston country: United States (us)
Abstract: The goal of the Chemistry Core is to provide a complete support of the PPG activities in terms of access to synthetic molecular probes to be used for the investigation of general anesthetic binding sites of ligand-gated receptors of y-aminobutyric acid (GABAA) acetylcholine and serotonin . The probes will represent analogs of four major classes of anesthetics that interact with these receptors, and will be used for studying the corresponding multiple binding sites on these receptors. The most important aspects of our structural and synthetic design is to produce photoactivatable analogs with minimal structure alteration to retain high binding affinity and to ensure the analogous modes of binding to those of the parent molecules, and to permit synthesis of the radiolabeled molecules with the highest specific radioactivity possible. We will synthesize analogs of the following groups of receptor ligands (i) propofol, a GABAA receptor ligand and a potent clinically used general anesthetic; (ii) barbituric acid, a ligand of GABAA and nicotinic acetylcholine receptors; (iii) long-chain aliphatic and aromatic alcohols, ligands that have binding sites on all members of the superfamily; and (iv) etomidate, another potent ligand that binds in the anesthetic site of GABAA receptors. In addition, when needed, we will resynthesize any needed ligand that has previously been used by the PPG. The leadership of the Core has been assumed by Dr. Bruzik in Chicago. A small part of the Core remains at MGH for the distribution and maintenance of stocks of existing photolabels. Administratively, the Core is structured with the Program Director as PI and a subcontract to the University of Illinois, Chicago. RELEVANCE (See Instmctions)
Keywords: Acetylcholine; Affinity; Alcohols; Aminobutyric Acids; analog; Anesthetics; Barbiturates; barbituric acid; barbituric acid salt; base; Binding (Molecular Function); Binding Sites; Chemistry; Chicago; Cholinergic Receptors; Data; design; Diazomethane; Ensure; Etomidate; Gated Ion Channel; General anesthetic drugs; Goals; I125 isotope; Illinois; Investigation; Label; Leadership; Length; Ligand Binding; Ligands; Maintenance; Maps; member; Modeling; Modification; Molecular Probes; New Agents; Nicotinic Receptors; Parents; Pentobarbital; Pharmacology; pharmacophore; Phenobarbital; Positioning Attribute; programs; Propofol; Radioactivity; Radiolabeled; radiotracer; Reagent; receptor; Serotonin; Site; Structure; Synthesis Chemistry; Tritium; Universities
Budget start date: 1-SEP-2011
Budget end date: 31-AUG-2012
5P01GM058448-13_6852 (2011): $157779
PROJECT 2: ACTION OF GENERAL ANESTHETICS ON TRANSIENT STATES OF LIGAND-GATED ION
W Keith
Massachusetts General Hospitalcity: Boston country: United States (us)
Abstract: instnjctions) The overall aim is to gain a better understanding of the manner in which general anesthetics interact with the activated states of the ligand-gated ion channels of the Cys-loop superfamily. The overall hypothesis is that general anesthetics interact with these channels at allosteric sites whose properties vary with the channel´s conformational state. A given binding site´s size and affinity for anesthetics varies with time as the receptor changes its conformation following addition of agonist. The approach is structured to encourage a tight integration between kinetic and structural approaches with kinetic studies generating hypotheses about the relative affinity of anesthetics for specific transient conformational states and time-resolved freeze quenched photolabeling being used to detemriine the degree of photoincorporation and to locate anesthetic sites. Aims 1 and 2 probe the mechanisms and binding sites involved in anesthetic enhancement of agonist- induced ion currents. Aim 1 addresses this issue for the cationic members of the family where only the smallest anesthetics enhance currents. The specific hypothesis to be tested is that the enhancing site increases in size as the receptor passes from the closed to the open and then desensitized states. The kinetics of this are most easily dissected on the slowest member of the superfamily, the human neuronal 5 HT3AR. Aim 2 will locate the enhancing site in human neuronal GABAARs in collaboration with Project 3 and using photoactivable anesthetics from the etomidate, propofol, barbiturate and alcohol families. The second part of this aim asks whether the site at which etomidate itself activates GABA currents is the same as that which enhances agonist-induced currents. Aim 3 explores the role of binding sites at the subunit interface vs. those in the ion channel in inhibition and enhancement using probes specifically designed for the task. This work will use the Torpedo acetylcholine receptor because its known structure will facilitate interpretation. In each aim, the receptor chosen is that best suited to answering the question. Photolabels and purified, heterologously expressed receptors will be provided by the Synthetic Chemistry and Protein Production Cores respectively, and sequencing by the Protein Chemistry Core. RELEVANCE (See instructions)
Keywords: Acetylcholine; Address; Affect; Affinity; Agonist; Alcohols; Allosteric Site; Amino Acids; Anesthetics; Barbiturates; barbituric acid salt; Binding (Molecular Function); Binding Sites; Cations; Cholinergic Receptors; Collaborations; Core Protein; design; Dissection; Enhancers; Etomidate; Excision; Family; Family member; Freezing; gamma-Aminobutyric Acid; Gated Ion Channel; General Anesthesia; General anesthetic drugs; Goals; Human; Instruction; Ion Channel; Ions; Kinetics; Left; Ligands; member; Modeling; Molecular Conformation; Neurons; Nicotinic Receptors; Pharmacology; Production; programs; Property; Propofol; Protein Chemistry; Publishing; receptor; receptor function; Relative (related person); research study; Residencies; Role; serotonin receptor; Site; Structure; Synthesis Chemistry; synthetic protein; Testing; Time; Torpedo; Work
Budget start date: 1-SEP-2011
Budget end date: 31-AUG-2012
5P01GM058448-13_6849 (2011): $472631
CORE A: SCIENTIFIC AND ADMINISTRATIVE CORE
W Keith
Massachusetts General Hospitalcity: Boston country: United States (us)
Keywords: Gated Ion Channel; General anesthetic drugs; Individual; Ligands; meetings; Occupational activity of managing finances; Office of Administrative Management; Site; Time
Budget start date: 1-SEP-2011
Budget end date: 31-AUG-2012
5P01GM058448-13_6851 (2011): $42769
Grants awarded to W Keith
BASIC SCIENCE RESEARCH TRAINING FOR ANESTHETISTS
W Keith
Massachusetts General Hospitalcity: Boston country: United States (us)
Grant 5T32GM007592-34 from National Institute Of General Medical Sciences
Abstract: We seek to continue a basic science research training program for anesthetists, now in its thirtieth year, in order to broaden the academic base of anesthesia through the development of physicians with basic science skills. We offer a group of carefully selected anesthetists the opportunity to join one of the basic science programs at Harvard Medical School or the Massachusetts Institute of Technology to work with an outstanding fundamental investigator in a wide range of subjects for a period of not less than two years. These subjects include, but are not limited to, pharmacology, neurobiology, molecular biology, toxicology, physiology, biochemistry, endocrinology, metabolism, biophysics and bioengineering. Special efforts will be made to attract minority applicants. This is a tutorial program, individualized to meet the needs and interests of each trainee. In addition to laboratory work, course work will be required. Some trainees will already have research training; for them refresher courses may be necessary. Others will need more extensive course work, and in the past some of these have elected to enroll in an appropriate graduate school program at Harvard or MIT. The overall objective is to produce a cadre of anesthesiologists, well trained in laboratory science and knowledgeable in their area of expertise, who will have the ability to continue on to independent research careers in problems of importance to anesthesia and the basic sciences upon which it rests. We have an outstanding track record of producing researchers who continue in academic medicine and who are successful at obtaining their own funding
Keywords: Basic Science; Research Training
Project start date: 1978-07-01
Project end date: 2013-06-30
Budget start date: 1-JUL-2011
Budget end date: 30-JUN-2012
PFA/PA: PA-06-468
5T32GM007592-34 (2011): $413713
NEUROIMMUNE MECHANISMS OF DEPRESSIVE-LIKE BEHAVIOR DURING AGING
W Keith, Professor Of Immunophysiology
University Of Illinois Urbana-champaigncity: Champaign country: United States (us)
Grant 5R01AG029573-05 from National Institute On Aging
Abstract: Inflammation is now recognized to be responsible for major health problems of the aging population, contributing to costly diseases such as obesity, the metabolic syndrome, heart disease and insulin resistance in type-2 diabetes. The chronic process of even healthy aging is also associated with development of low grade inflammation. However, age-related changes in inflammation have mainly been considered in relation to systemic disorders. We and others have now collected substantial evidence to show that this inflammation status, as defined by the overexpression of proinflammatory cytokines, is not restricted to the periphery but is also found in the brain. Brain inflammation causes symptoms of sickness that are usually associated with microbial infections, which is likely to make an important contribution to the comorbid behavioral and psychological disturbances that occur in the elderly. Indeed, one in five individuals over the age of 65 suffer from depressive disorders, which is more than twice the prevalence found in the general population. A likely mechanism for the increased prevalence of depressive disorders during aging is a reduction in the synthesis of serotonin, a key neurotransmitter in the regulation of mood, caused by proinflammatory cytokines acting in the brain. This action is mediated by immune-induced activation of the tryptophan-degrading enzyme, indoleamine 2,3 dioxygenase (IDO). This process decreases the bioavailability of tryptophan for the synthesis of serotonin. Our preliminary data indicate that peripheral immune activation activates IDO and induces depressive-like behavioral alterations, and these effects are exacerbated in aged compared to adult mice. Based on this evidence, we propose that peripheral immune activation precipitates the occurrence of mood disorders in aged individuals. We propose to test this hypothesis in aged mice exposed to both acute and chronic peripheral immune activation, two events that we have already shown to increase brain IDO activity. In the first objective, we will determine whether the depressive-like behavioral alterations that develop in response to both acute and chronic peripheral immune activation are exacerbated in aged mice. In the second objective, we will assess the role of increases in peripheral and brain IDO, as well as brain tryptophan and serotonin, in these behavioral changes, whereas the third objective will determine the contribution of brain glial cells to the age-associated increase in brain IDO. We will then use novel pharmacological approaches to determine if targeting brain inflammation (Objective 4) or brain IDO (Objective 5) attenuates the functional consequences of aging on development of depressive like behavior. These exciting experiments will be the first to use integrative neuroimmune approaches to evaluate IDO as the critical mediator between the age-related increase in peripheral and brain inflammation and the increased prevalence of mood disorders in aged individuals
Keywords: Acute; Adult; Affect; Age; age related; aged; Aging; aging brain; aging population; Aging-Related Process; Anhedonia; Anxiety; Attenuated; base; Behavior; Behavioral; Biological Availability; Brain; C-reactive protein; Calmette-Guerin Bacillus; Cancer Patient; Cardiovascular Diseases; Cells; Chronic; Clinical; cytokine; Data; Depressed mood; Depressive disorder; depressive symptoms; Desire for food; Development; Dioxygenases; Disease; Disease Resistance; Elderly; Encephalitis; Enzymes; Event; Experimental Models; falls; Fatigue; Feeling suicidal; General Population; Goals; Health; healthy aging; Heart Diseases; Hepatitis C; Human; hypomania; Immune; immune activation; Immune response; Immune system; Immunity; Immunocompetence; Immunotherapy; Individual; indoleamine; Infection; Inflammation; Inflammatory; Injection of therapeutic agent; innovation; Insulin Resistance; Interferons; Interleukin-1; Interleukin-2; Kynurenine; Laboratories; Lead; Life; macrophage; Malignant Neoplasms; Mediating; Mediator of activation protein; Mental Depression; Metabolic syndrome; Metabolism; Metastatic Melanoma; microbial; Microglia; Molecular; Mood Disorders; mood regulation; Mus; neurobiological mechanism; Neuroglia; Neuroimmunomodulation; neuroinflammation; neuropathology; neurotransmission; Neurotransmitters; Non-Insulin-Dependent Diabetes Mellitus; normal aging; novel; novel therapeutics; Obesity; older patient; overexpression; Pathogenesis; Patients; Pattern; Peripheral; Plasma; Play; Population; Prevalence; prevent; Process; programs; psychologic; Psychopathology; Recording of previous events; Renal carcinoma; Research; Research Personnel; research study; response; Rheumatoid Arthritis; Role; Serotonin; Serum; Signal Transduction; Sleep; Staging; Symptoms; T-Lymphocyte; Testing; Tryptophan; Tryptophan Metabolism Pathway; Tumor Necrosis Factor-alpha
Project start date: 2007-04-01
Project end date: 2012-03-31
Budget start date: 1-APR-2011
Budget end date: 31-MAR-2012
5R01AG029573-05 (2011): $597835
NEUROPROTECTION BY A NUCLEAR CARBONIC ANHYDRASE IN C. ELEGANS
W Keith, Asscociate Prof Of Medicine
University Of Rochestercity: Rochester country: United States (us)
Grant 5R01NS064945-02 from National Institute Of Neurological Disorders And Stroke
Abstract: Carbonic anhydrase (CA) catalyzes the conversion of CO2 to a proton (H+) and bicarbonate (HCO3-) and is involved in many physiologic and pathophysiologic processes. Our preliminary data demonstrate that the nematode C. elegans expresses a CA that selectively localizes to the cell nucleus, is induced by hypoxia, and when lost results in neurodegeneration (ie dysfunction followed by cell death). This is the first example of a classic a-CA that is targeted to the nucleus in any organism. Our central hypothesis is that nuclear CA (NCA) activity protects neurons from hypoxic stress by buffering nuclear pH. We have developed a set of tools that will allow us to study neurodegeneration in a stain that is deficient in NCA and to assess whether its activity is significant for physiologic responses to hypoxia. We will also study signaling processes that are relevant to NCA expression. Finally, using novel genetically-encoded biosensors we will test whether nuclear CA can buffer pH in neuronal nuclei and what effect this has on nuclear redox status (or oxidative stress, which follows hypoxia). All of these approaches will utilize integrative physiologic techniques in live worms. These experiments are geared toward defining the mechanism whereby nuclear CA promotes cell function and viability. A second goal of this proposal is to test whether nuclear CA activity protects mammalian neurons during ischemia. Preliminary evidence demonstrates that transgenic expression of the nematode nuclear CA in mammalian cortical neurons is protective during oxygen-glucose deprivation and hypoxia. In addition to pursuing these studies, the cortical cell culture model will be used as a tissue source for a biochemical approach to identifying a predicted endogenous mammalian NCA. There are currently two candidate genes that are induced by hypoxia and cell stress, respectively, that will be examined using immunologic techniques and recombinant expression assays. In addition, a mouse middle cerebral artery ligation stroke model will be used to determine whether endogenous NCA activity is regulated by hypoxia in an intact brain, with a focus on our two candidate gene products. We hypothesize that worms require a dedicated nuclear CA because of their constant exposure to the environment, but that mammals express or target a CA to the nucleus only under stress conditions. The experiments proposed in this application are focused on defining a novel neuroprotective mechanism that involves pH and electrolyte homeostasis in the cell nucleus mediated by nuclear CA, and as such bridges two relatively diverse, but extremely significant, areas of biology. We have identified an a-carbonic anhydrase in the genetic model organism C. elegans that regulates neuronal cell death decisions that occur in response to stress, and in particular hypoxia, by buffering the pH of the nucleus. Nuclear pH regulation is a novel mechanism for protecting neurons against ischemia and/or oxidative stress such as occurs in neurodegenerative disease. This application is focused on understanding the mechanism behind nuclear CAs protective effects in nematodes and translating these findings to mammals as a way of targeting cognitive impairment
Keywords: Ablation; Address; Anabolism; Animal Model; Area; Attenuated; Automobile Driving; Behavioral Assay; Bicarbonates; Biochemical; Biological Assay; Biology; Biosensor; bone; Brain; Buffers; Caenorhabditis elegans; Candidate Disease Gene; Carbon Dioxide; carbonate dehydratase; Catalytic Domain; Cell Culture Techniques; Cell Death; Cell Nucleus; Cell physiology; Cell Survival; Cells; cellular imaging; Cellular Morphology; Cellular Stress; Cerebrum; computerized data processing; Cytoplasm; Data; deprivation; design; Disease; Electrolytes; Environment; Equilibrium; Exposure to; Fatty acid glycerol esters; Functional disorder; Gene Expression Regulation; Genetic; Genetic Models; Glucose; Goals; Homeostasis; Human; Hypoxia; Hypoxia Inducible Factor; Immunologic Techniques; Impaired cognition; improved; Injury; Ischemia; Label; Lesion; Life; Ligation; loss of function; Mammals; man; Measures; Mediating; Memory; middle cerebral artery; Minerals; Modeling; Molecular; mouse model; Mus; mutant; Nematoda; Nerve Degeneration; Nervous system structure; Neurodegenerative Disorders; neuron loss; Neurons; neuroprotection; novel; Nuclear; Organism; Orthologous Gene; Output; overexpression; Oxidation-Reduction; Oxidative Stress; Oxygen; pH Homeostasis; Phenotype; Physiological; Physiological Processes; preconditioning; Process; Promotor (Genetics); protective effect; Proteins; Protons; public health relevance; Recombinants; Regulation; Reporter; research study; Respiration; response; Role; Signal Transduction; Slice; Source; Staining method; Stains; Stress; stress management; stroke; sugar; synaptic function; Techniques; Testing; therapeutic target; Tissues; tool; Transgenes; Transgenic Organisms; Translating; Tumor Markers; Variant; Work
Project start date: 2010-09-01
Project end date: 2015-05-31
Budget start date: 1-JUN-2011
Budget end date: 31-MAY-2012
PFA/PA: PA-10-067
5R01NS064945-02 (2011): $327994
C. ELEGANS AND MITOCHONDRIAL K+ CHANNELS
W Keith, Assistant Professor
University Of Rochestercity: Rochester country: United States (us)
Grant 5R01GM087483-02 from National Institute Of General Medical Sciences
Abstract: Acute myocardial infarction is a leading cause of death throughout the world, while stroke is the third leading cause of death in the United States. Ischemia-reperfusion injury associated with these conditions can lead to permanent tissue damage or neurologic deficits. It is well recognized that non-lethal exposure to ischemia for short periods of time however, elicits a proadaptive response that protects cells from subsequent ischemic injury in a process referred to as preconditioning. Mitochondria are central to the pathogenesis of ischemia- perfusion injury and are believed to be a major target for preconditioning. In particular, ion channels in the inner mitochondrial membrane that transport potassium (KATP and KCa channels) are believed to attenuate the mitochondrial cell death response following preconditioning. The molecular identity of these channels is controversial. The major goal of this proposal is to unambiguously identify the mitochondrial KATP and KCa channels, and a second goal is to identify signaling processes that regulate channel activity in the mitochondria in response to preconditioning. The experiments designed to meet these goals will be carried out in the nematode C. elegans. It has recently been shown that preconditioning can protect this genetic model organism from hypoxic injury and death. Moreover, we have found that C. elegans express functional KATP and KCa channels in their mitochondria. We propose to combine the strengths of two investigators, one with extensive experience in mitochondrial bioenergetics and cardiovascular physiology, and the other in nematode ion channel physiology, to test the hypothesis that KATP and KCa channel regulation is an evolutionarily conserved mechanism that contributes to preconditioning in C. elegans. We will utilize the vast array of genetic resources available in C. elegans to screen strains containing mutations in candidate genes for channel activity in purified mitochondria, for channel regulation via conserved signaling pathways, and for their ability to be preconditioned. The results from these experiments will improve our ability to develop protective therapeutics targeted at channels or upstream regulators and designed to mimic the effects of preconditioning in mammals. Reduced oxygen availability causes cellular damage and death, particularly in neurons (via stroke) or cardiac myocytes (via heart attack). However, brief sub-lethal exposure to low oxygen can lead to proadaptive mechanisms that protect against subsequent decreases in oxygen. This process is called "preconditioning" and acts as an evolutionarily conserved early warning system in all cell types and organisms examined so far. We propose to determine the molecular identity of membrane ion transporters that have been implicated in this proadaptive conditioning via their function in the mitochondria and to study their regulation using the genetic model organism C. elegans. The identification of these molecules will help in the development of new therapies for heart attack and stroke
Keywords: Acute myocardial infarct; Acute myocardial infarction; Address; Adenosine Cyclic Monophosphate-Dependent Protein Kinases; Anesthestic Drugs; Anesthetic Agents; Anesthetic Drugs; Anesthetics; Animal Model; Animal Models and Related Studies; Apoplexy; Atpenin A 5; atpenin A5; Attenuated; Autoregulation; Bioenergetic; Bioenergetics; biological signal transduction; Blood Vessels; Body Tissues; brain attack; C elegans; C.elegans; Caenorhabditis elegans; cAMP-Dependent Protein Kinases; Candidate Disease Gene; Candidate Gene; Cardiac; cardiac infarct; Cardiac infarction; Cardiac Myocytes; Cardiocyte; cardiomyocyte; cardiovascular function; Cardiovascular Physiology; Cause of Death; Cell Communication and Signaling; Cell Death; Cell Signaling; cell type; Cells; Cerebral Stroke; cerebral vascular accident; Cerebrovascular accident; Cerebrovascular Apoplexy; Cerebrovascular Stroke; Cessation of life; Chimera Protein; Chimeric Proteins; clinical data repository; clinical data warehouse; Complex; computerized data processing; conditioning; coronary attack; coronary infarct; coronary infarction; Cyclic AMP-Dependent Protein Kinases; Data; Data Banks; Data Bases; data processing; data repository; Databank, Electronic; Databanks; Database, Electronic; Databases; Death; design; designing; Development; DNA Alteration; DNA mutation; experience; experiment; experimental research; experimental study; Exposure to; fumarate hydrogenase; Fumarate Reductase; Fusion Protein; Gene Alteration; Gene Mutation; Genes; Genetic; Genetic Alteration; Genetic Change; Genetic defect; Genetic Models; Genetic mutation; genetic resource; genome mutation; Goals; heart attack; heart infarct; heart infarction; Heart myocyte; heavy metal lead; heavy metal Pb; Homeostasis; Hypoxia; Hypoxic; improved; Injury; Inner mitochondrial membrane; Intracellular Communication and Signaling; Investigators; Ion Channel; Ion Channels, Potassium; Ionic Channels; Ions; Ischemia; Ischemia-Reperfusion Injury; Ischemic Preconditioning; K channel; K element; Knockout Mice; Laboratories; Lead; Life; living system; Malonates; Mammalia; Mammals; Mammals, General; Measures; Mediator; Mediator of Activation; Mediator of activation protein; meetings; Membrane; Membrane Channels; membrane structure; Membrane Transport; Mice, Knock-out; Mice, Knockout; Mitochondria; mitochondrial; Mitochondrial Proteins; model organism; Modeling; Molecular; Morbidity; Morbidity - disease rate; Mortality; Mortality Vital Statistics; Muscle Cells, Cardiac; Muscle Cells, Heart; mutant; Mutation; Myocardial Infarct; Myocardial Infarction; Myocytes, Cardiac; necrocytosis; Nematoda; Nematodes; Nerve Cells; Nerve Unit; Neural Cell; Neurocyte; Neurologic Deficit; neuronal; Neurons; novel; Null Mouse; O element; O2 element; Organism; Ortholog; Orthologous Gene; Oxygen; Oxygen Deficiency; Pathogenesis; Pb element; Perfusion; Physiological Homeostasis; Physiology; PKA; Potassium; Potassium Channel; preconditioning; Preconditionings, Ischemic; Process; Production; Protein Kinase A; public health relevance; Reagent; Regulation; relational database; reperfusion; Reperfusion Damage; Reperfusion Injury; Reperfusion Therapy; Research Personnel; research study; Researchers; response; Role; roundworm; SDH; Sequence Alteration; Signal Pathway; signal processing; Signal Transduction; Signal Transduction Systems; Signaling; Signaling Molecule; social role; stroke; Stroke; Succinate Dehydrogenase; Succinic Dehydrogenase; Succinic Oxidase; Surface; System; System, LOINC Axis 4; Testing; therapeutic target; Time; Tissues; trafficking; Transmembrane Transport; United States; vascular; Vascular Accident, Brain
Relevance: NARRATIVE: Reduced oxygen availability causes cellular damage and death, particularly in neurons (via stroke) or cardiac myocytes (via heart attack). However, brief sub-lethal exposure to low oxygen can lead to proadaptive mechanisms that protect against subsequent decreases in oxygen. This process is called "preconditioning" and acts as an evolutionarily conserved early warning system in all cell types and organisms examined so far. We propose to determine the molecular identity of membrane ion transporters that have been implicated in this proadaptive conditioning via their function in the mitochondria and to study their regulation using the genetic model organism C. elegans. The identification of these molecules will help in the development of new therapies for heart attack and stroke
Project start date: 2010-01-01
Project end date: 2013-12-31
Budget start date: 1-JAN-2011
Budget end date: 31-DEC-2011
PFA/PA: PA-07-070
5R01GM087483-02 (2011): $276750
5R01GM087483-03 (2012): $275319