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Titus HE, Xu H, Robinson AP, Patel PA, Chen Y, Fantini D, Eaton V, Karl M, Garrison ED, Rose IVL, Chiang MY, Podojil JR, Balabanov R, Liddelow SA, Miller RH, Popko B, Miller SD. Repurposing the cardiac glycoside digoxin to stimulate myelin regeneration in chemically-induced and immune-mediated mouse models of multiple sclerosis. Glia 2022; 70:1950-1970. [PMID: 35809238 PMCID: PMC9378523 DOI: 10.1002/glia.24231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 06/07/2022] [Accepted: 06/14/2022] [Indexed: 11/24/2022]
Abstract
Multiple sclerosis (MS) is a central nervous system (CNS) autoimmune disease characterized by inflammation, demyelination, and neurodegeneration. The ideal MS therapy would both specifically inhibit the underlying autoimmune response and promote repair/regeneration of myelin as well as maintenance of axonal integrity. Currently approved MS therapies consist of non-specific immunosuppressive molecules/antibodies which block activation or CNS homing of autoreactive T cells, but there are no approved therapies for stimulation of remyelination nor maintenance of axonal integrity. In an effort to repurpose an FDA-approved medication for myelin repair, we chose to examine the effectiveness of digoxin, a cardiac glycoside (Na+ /K+ ATPase inhibitor), originally identified as pro-myelinating in an in vitro screen. We found that digoxin regulated multiple genes in oligodendrocyte progenitor cells (OPCs) essential for oligodendrocyte (OL) differentiation in vitro, promoted OL differentiation both in vitro and in vivo in female naïve C57BL/6J (B6) mice, and stimulated recovery of myelinated axons in B6 mice following demyelination in the corpus callosum induced by cuprizone and spinal cord demyelination induced by lysophosphatidylcholine (LPC), respectively. More relevant to treatment of MS, we show that digoxin treatment of mice with established MOG35-55 -induced Th1/Th17-mediated chronic EAE combined with tolerance induced by the i.v. infusion of biodegradable poly(lactide-co-glycolide) nanoparticles coupled with MOG35-55 (PLG-MOG35-55 ) completely ameliorated clinical disease symptoms and stimulated recovery of OL lineage cell numbers. These findings provide critical pre-clinical evidence supporting future clinical trials of myelin-specific tolerance with myelin repair/regeneration drugs, such as digoxin, in MS patients.
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Affiliation(s)
- Haley E. Titus
- Department of Microbiology‐Immunology and the Interdepartmental Immunobiology CenterNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Huan Xu
- NeurologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Andrew P. Robinson
- Department of Microbiology‐Immunology and the Interdepartmental Immunobiology CenterNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Priyam A. Patel
- Quantitative Data Science Core Center for Genetic MedicineNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Yanan Chen
- NeurologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Damiano Fantini
- UrologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Valerie Eaton
- Department of Microbiology‐Immunology and the Interdepartmental Immunobiology CenterNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Molly Karl
- Department of Anatomy and Cell BiologyThe George Washington University School of Medicine and Health SciencesWashingtonDistrict of ColumbiaUSA
| | - Eric D. Garrison
- Department of Anatomy and Cell BiologyThe George Washington University School of Medicine and Health SciencesWashingtonDistrict of ColumbiaUSA
| | - Indigo V. L. Rose
- Neuroscience Institute and Departments of Neuroscience, & Physiology, and OphthalmologyNew York University Grossman School of MedicineNew YorkNew YorkUSA
| | - Ming Yi Chiang
- Department of Microbiology‐Immunology and the Interdepartmental Immunobiology CenterNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Joseph R. Podojil
- Department of Microbiology‐Immunology and the Interdepartmental Immunobiology CenterNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
- Cour Pharmaceutical Development CompanyNorthbrookIllinoisUSA
| | - Roumen Balabanov
- NeurologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Shane A. Liddelow
- Neuroscience Institute and Departments of Neuroscience, & Physiology, and OphthalmologyNew York University Grossman School of MedicineNew YorkNew YorkUSA
| | - Robert H. Miller
- Department of Anatomy and Cell BiologyThe George Washington University School of Medicine and Health SciencesWashingtonDistrict of ColumbiaUSA
| | - Brian Popko
- NeurologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Stephen D. Miller
- Department of Microbiology‐Immunology and the Interdepartmental Immunobiology CenterNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
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Titus HE, Chen Y, Podojil JR, Robinson AP, Balabanov R, Popko B, Miller SD. Pre-clinical and Clinical Implications of "Inside-Out" vs. "Outside-In" Paradigms in Multiple Sclerosis Etiopathogenesis. Front Cell Neurosci 2020; 14:599717. [PMID: 33192332 PMCID: PMC7654287 DOI: 10.3389/fncel.2020.599717] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 10/06/2020] [Indexed: 12/15/2022] Open
Abstract
Multiple Sclerosis (MS) is an immune-mediated neurological disorder, characterized by central nervous system (CNS) inflammation, oligodendrocyte loss, demyelination, and axonal degeneration. Although autoimmunity, inflammatory demyelination and neurodegeneration underlie MS, the initiating event has yet to be clarified. Effective disease modifying therapies need to both regulate the immune system and promote restoration of neuronal function, including remyelination. The challenge in developing an effective long-lived therapy for MS requires that three disease-associated targets be addressed: (1) self-tolerance must be re-established to specifically inhibit the underlying myelin-directed autoimmune pathogenic mechanisms; (2) neurons must be protected from inflammatory injury and degeneration; (3) myelin repair must be engendered by stimulating oligodendrocyte progenitors to remyelinate CNS neuronal axons. The combined use of chronic and relapsing remitting experimental autoimmune encephalomyelitis (C-EAE, R-EAE) (“outside-in”) as well as progressive diphtheria toxin A chain (DTA) and cuprizone autoimmune encephalitis (CAE) (“inside-out”) mouse models allow for the investigation and specific targeting of all three of these MS-associated disease parameters. The “outside-in” EAE models initiated by myelin-specific autoreactive CD4+ T cells allow for the evaluation of both myelin-specific tolerance in the absence or presence of neuroprotective and/or remyelinating agents. The “inside-out” mouse models of secondary inflammatory demyelination are triggered by toxin-induced oligodendrocyte loss or subtle myelin damage, which allows evaluation of novel therapeutics that could promote remyelination and neuroprotection in the CNS. Overall, utilizing these complementary pre-clinical MS models will open new avenues for developing therapeutic interventions, tackling MS from the “outside-in” and/or “inside-out”.
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Affiliation(s)
- Haley E Titus
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Yanan Chen
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Joseph R Podojil
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.,Cour Pharmaceutical Development Company, Inc., Northbrook, IL, United States
| | - Andrew P Robinson
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Roumen Balabanov
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Brian Popko
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Stephen D Miller
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.,Cour Pharmaceutical Development Company, Inc., Northbrook, IL, United States.,Interdepartmental Immunobiology Center, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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Bordone MP, Salman MM, Titus HE, Amini E, Andersen JV, Chakraborti B, Diuba AV, Dubouskaya TG, Ehrke E, Espindola de Freitas A, Braga de Freitas G, Gonçalves RA, Gupta D, Gupta R, Ha SR, Hemming IA, Jaggar M, Jakobsen E, Kumari P, Lakkappa N, Marsh APL, Mitlöhner J, Ogawa Y, Paidi RK, Ribeiro FC, Salamian A, Saleem S, Sharma S, Silva JM, Singh S, Sulakhiya K, Tefera TW, Vafadari B, Yadav A, Yamazaki R, Seidenbecher CI. The energetic brain - A review from students to students. J Neurochem 2019; 151:139-165. [PMID: 31318452 DOI: 10.1111/jnc.14829] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 07/03/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022]
Abstract
The past 20 years have resulted in unprecedented progress in understanding brain energy metabolism and its role in health and disease. In this review, which was initiated at the 14th International Society for Neurochemistry Advanced School, we address the basic concepts of brain energy metabolism and approach the question of why the brain has high energy expenditure. Our review illustrates that the vertebrate brain has a high need for energy because of the high number of neurons and the need to maintain a delicate interplay between energy metabolism, neurotransmission, and plasticity. Disturbances to the energetic balance, to mitochondria quality control or to glia-neuron metabolic interaction may lead to brain circuit malfunction or even severe disorders of the CNS. We cover neuronal energy consumption in neural transmission and basic ('housekeeping') cellular processes. Additionally, we describe the most common (glucose) and alternative sources of energy namely glutamate, lactate, ketone bodies, and medium chain fatty acids. We discuss the multifaceted role of non-neuronal cells in the transport of energy substrates from circulation (pericytes and astrocytes) and in the supply (astrocytes and microglia) and usage of different energy fuels. Finally, we address pathological consequences of disrupted energy homeostasis in the CNS.
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Affiliation(s)
- Melina Paula Bordone
- Facultad de Farmacia y Bioquímica, Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mootaz M Salman
- Department of Cell Biology, Harvard Medical School, and Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Haley E Titus
- Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Elham Amini
- Department of Medicine, University Kebangsaan Malaysia Medical Centre (HUKM), Cheras, Kuala Lumpur, Malaysia
| | - Jens V Andersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Artem V Diuba
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Tatsiana G Dubouskaya
- Institute of Biophysics and Cell Engineering, National Academy of Sciences of Belarus, Minsk, Belarus
| | - Eric Ehrke
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany
| | - Andiara Espindola de Freitas
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, California, USA
| | | | | | | | - Richa Gupta
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Sharon R Ha
- Baylor College of Medicine, Houston, Texas, USA
| | - Isabel A Hemming
- Brain Growth and Disease Laboratory, The Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia.,School of Medicine and Pharmacology, The University of Western Australia, Crawley, Australia
| | - Minal Jaggar
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Emil Jakobsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Punita Kumari
- Defense Institute of Physiology and allied sciences, Defense Research and Development Organization, Timarpur, Delhi, India
| | - Navya Lakkappa
- Department of Pharmacology, JSS college of Pharmacy, Ooty, India
| | - Ashley P L Marsh
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Jessica Mitlöhner
- Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany
| | - Yuki Ogawa
- The Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | | | | | - Ahmad Salamian
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Suraiya Saleem
- CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Sorabh Sharma
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Joana M Silva
- Life and Health Sciences Research Institute (ICVS), Medical School, University of Minho, Braga, Portugal
| | - Shripriya Singh
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Kunjbihari Sulakhiya
- Department of Pharmacy, Indira Gandhi National Tribal University, Amarkantak, India
| | - Tesfaye Wolde Tefera
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Behnam Vafadari
- Institute of environmental medicine, UNIKA-T, Technical University of Munich, Munich, Germany
| | - Anuradha Yadav
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Reiji Yamazaki
- Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.,Center for Behavioral Brain Sciences (CBBS), Otto von Guericke University, Magdeburg, Germany
| | - Constanze I Seidenbecher
- Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany.,Center for Behavioral Brain Sciences (CBBS), Otto von Guericke University, Magdeburg, Germany
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Titus HE, López-Juárez A, Silbak SH, Rizvi TA, Bogard M, Ratner N. Oligodendrocyte RasG12V expressed in its endogenous locus disrupts myelin structure through increased MAPK, nitric oxide, and notch signaling. Glia 2017; 65:1990-2002. [PMID: 28856719 DOI: 10.1002/glia.23209] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/18/2017] [Accepted: 08/04/2017] [Indexed: 01/28/2023]
Abstract
Costello syndrome (CS) is a gain of function Rasopathy caused by heterozygous activating mutations in the HRAS gene. Patients show brain dysfunction that can include abnormal brain white matter. Transgenic activation of HRas in the entire mouse oligodendrocyte lineage resulted in myelin defects and behavioral abnormalities, suggesting roles for disrupted myelin in CS brain dysfunction. Here, we studied a mouse model in which the endogenous HRas gene is conditionally replaced by mutant HRasG12V in mature oligodendrocytes, to separate effects in mature myelinating cells from developmental events. Increased myelin thickness due to decompaction was detectable within one month of HRasG12V expression in the corpus callosum of adult mice. Increases in active ERK and Nitric Oxide (NO) were present in HRas mutants and inhibition of NO synthase (NOS) or MEK each partially rescued myelin decompaction. In addition, genetic or pharmacologic inhibition of Notch signaling improved myelin compaction. Complete rescue of myelin structure required dual drug treatments combining MAPK, NO, or Notch inhibition; with MEK + NOS blockade producing the most robust effect. We suggest that individual or concomitant blockade of these pathways in CS patients may improve aspects of brain function.
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Affiliation(s)
- Haley E Titus
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
| | - Alejandro López-Juárez
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
| | - Sadiq H Silbak
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
| | - Tilat A Rizvi
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
| | - Madeleine Bogard
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
| | - Nancy Ratner
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
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López-Juárez A, Titus HE, Silbak SH, Pressler JW, Rizvi TA, Bogard M, Bennett MR, Ciraolo G, Williams MT, Vorhees CV, Ratner N. Oligodendrocyte Nf1 Controls Aberrant Notch Activation and Regulates Myelin Structure and Behavior. Cell Rep 2017; 19:545-557. [PMID: 28423318 PMCID: PMC5828008 DOI: 10.1016/j.celrep.2017.03.073] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 02/23/2017] [Accepted: 03/27/2017] [Indexed: 11/29/2022] Open
Abstract
The RASopathy neurofibromatosis type 1 (NF1) is one of the most common autosomal dominant genetic disorders. In NF1 patients, neurological issues may result from damaged myelin, and mice with a neurofibromin gene (Nf1) mutation show white matter (WM) defects including myelin decompaction. Using mouse genetics, we find that altered Nf1 gene-dose in mature oligodendrocytes results in progressive myelin defects and behavioral abnormalities mediated by aberrant Notch activation. Blocking Notch, upstream mitogen-activated protein kinase (MAPK), or nitric oxide signaling rescues myelin defects in hemizygous Nf1 mutants, and pharmacological gamma secretase inhibition rescues aberrant behavior with no effects in wild-type (WT) mice. Concomitant pathway inhibition rescues myelin abnormalities in homozygous mutants. Notch activation is also observed in Nf1+/− mouse brains, and cells containing active Notch are increased in NF1 patient WM. We thus identify Notch as an Nf1 effector regulating myelin structure and behavior in a RASopathy and suggest that inhibition of Notch signaling may be a therapeutic strategy for NF1.
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Affiliation(s)
- Alejandro López-Juárez
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Haley E Titus
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Sadiq H Silbak
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Joshua W Pressler
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Tilat A Rizvi
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Madeleine Bogard
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Michael R Bennett
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Georgianne Ciraolo
- Division of Pathology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Michael T Williams
- Division of Neurology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Charles V Vorhees
- Division of Neurology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Nancy Ratner
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA.
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Alvarez FJ, Bullinger KL, Titus HE, Nardelli P, Cope TC. Permanent reorganization of Ia afferent synapses on motoneurons after peripheral nerve injuries. Ann N Y Acad Sci 2010; 1198:231-41. [PMID: 20536938 DOI: 10.1111/j.1749-6632.2010.05459.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
After peripheral nerve injuries to a motor nerve, the axons of motoneurons and proprioceptors are disconnected from the periphery and monosynaptic connections from group I afferents and motoneurons become diminished in the spinal cord. Following successful reinnervation in the periphery, motor strength, proprioceptive sensory encoding, and Ia afferent synaptic transmission on motoneurons partially recover. Muscle stretch reflexes, however, never recover and motor behaviors remain uncoordinated. In this review, we summarize recent findings that suggest that lingering motor dysfunction might be in part related to decreased connectivity of Ia afferents centrally. First, sensory afferent synapses retract from lamina IX, causing a permanent relocation of the inputs to more distal locations and significant disconnection from motoneurons. Second, peripheral reconnection between proprioceptive afferents and muscle spindles is imperfect. As a result, a proportion of sensory afferents that retain central connections with motoneurons might not reconnect appropriately in the periphery. A hypothetical model is proposed in which the combined effect of peripheral and central reconnection deficits might explain the failure of muscle stretch to initiate or modulate firing of many homonymous motoneurons.
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Affiliation(s)
- Francisco J Alvarez
- Department of Neurosciences, Cell Biology and Physiology, Wright State University, Dayton, Ohio, USA.
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Titus HE, Costanzo DJ. Effects of puromycin on learning in the toad. Psychol Rep 1972; 30:627-30. [PMID: 5024944 DOI: 10.2466/pr0.1972.30.2.627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Toads were tested to determine whether puromycin could produce memory blockage of a learned aversion for stinging honeybees. Although the drug disrupted the learned aversion, there was evidence that the noxious consequences of puromycin itself produced a generalized aversion in the feeding situation which interacted with the effects on memory.
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Titus HE. Strongylus Contortus in a Herd of Angora Goats. J Comp Med Vet Arch 1900; 21:423. [PMID: 36393771 PMCID: PMC9346917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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