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Hamed K, El-Fiky SA, M Gawish A, R H Mohamed H, Khalil WKB, Huang X, Hasan M, Zafar A, Caprioli G. Assessing the Efficacy of Fenugreek Saponin Nanoparticles in Attenuating Nicotine-Induced Hepatotoxicity in Male Rats. ACS OMEGA 2023; 8:42722-42731. [PMID: 38024695 PMCID: PMC10653053 DOI: 10.1021/acsomega.3c05526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/14/2023] [Indexed: 12/01/2023]
Abstract
During smoking, nicotine, the most bountiful compound in cigarettes, is absorbed into the body by the lungs and quickly metabolized in the liver, causing three major adverse impacts such as toxic, neoplastic, and immunomodulatory effects. Saponins extracted from several plants are reported to exhibit various biological actions, such as anticancer effects. So, the potential protective effect of fenugreek saponin and nanofenugreek saponin against toxicity induced by nicotine in male rats was investigated in this study. Animals were exposed to nicotine (1.5 mg/kg/day) and/or treated with fenugreek saponin (25, 50, and 100 mg/kg/day) and nanofenugreek saponin (20, 40, and 80 mg/kg/day). Comet assays, histopathological examination, and analyses for the expression levels of glutamate aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1) genes in liver tissues as well as the activity of glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were conducted. The results revealed that nicotine treatment induced a significant increase in DNA damage, decrease in the expression levels of (GLAST) and (GLT-1) genes, and increase in histopathological alterations in liver tissues. Moreover, nicotine treatment induced a significant reduction in the activity of antioxidant enzymes GPx and GST. On the other hand, administration of fenugreek saponin or nanofenugreek saponin with nicotine significantly decreased the DNA damage, increased the expression levels of (GLAST) and (GLT-1) genes, and decreased histopathological alterations in liver tissues. Additionally, a significant increase in the activities of GPx and GST was observed. The results suggested that DNA damage and histological injuries induced by nicotine were decreased by the administration of fenugreek saponin or nanofenugreek saponin; thus, fenugreek saponin and nanofenugreek saponin can be used as ameliorative agents against nicotine toxicity.
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Affiliation(s)
- Karima
A. Hamed
- Department
of Cell Biology, National Research Centre, 33 El-Bohous St, 12622 Dokki, Giza, P.O. 12622, Egypt
| | - Saima A. El-Fiky
- Department
of Cell Biology, National Research Centre, 33 El-Bohous St, 12622 Dokki, Giza, P.O. 12622, Egypt
| | - Azza M Gawish
- Department
of Zoology, Faculty of Science, Cairo University, Cairo 12622, Giza, Egypt
| | - Hanan R H Mohamed
- Department
of Zoology, Faculty of Science, Cairo University, Cairo 12622, Giza, Egypt
| | - Wagdy K. B. Khalil
- Department
of Zoology, Faculty of Science, Cairo University, Cairo 12622, Giza, Egypt
| | - Xue Huang
- School
of Chemistry and Chemical Engineering, Zhongkai
University of Agriculture and Engineering, Guangzhou 510225, P. R. China
| | - Murtaza Hasan
- Faculty
of Biological and Chemical Science, Department of Biotechnology, The Islamia University of Bahawalpur, Punjab 63100, Pakistan
- School
of Chemistry and Chemical Engineering, Zhongkai
University of Agriculture and Engineering, Guangzhou 510225, P. R. China
| | - Ayesha Zafar
- Department
of Biomedical Engineering, College of Future Technology, Peking University, Beijing 510225, P. R. China
| | - Giovanni Caprioli
- Chemistry
Interdisciplinary Project (CHip), School of Pharmacy, University of Camerino, Camerino 62032, Italy
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2
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Pradhan SS, Thota SM, Rajaratnam S, Bhagavatham SKS, Pulukool SK, Rathnakumar S, Phalguna KS, Dandamudi RB, Pargaonkar A, Joseph P, Joshy EV, Sivaramakrishnan V. Integrated multi-omics analysis of Huntington disease identifies pathways that modulate protein aggregation. Dis Model Mech 2022; 15:dmm049492. [PMID: 36052548 PMCID: PMC10655815 DOI: 10.1242/dmm.049492] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 08/15/2022] [Indexed: 11/20/2022] Open
Abstract
Huntington disease (HD) is a neurodegenerative disease associated with polyglutamine expansion in the protein huntingtin (HTT). Although the length of the polyglutamine repeat correlates with age at disease onset and severity, psychological, cognitive and behavioral complications point to the existence of disease modifiers. Mitochondrial dysfunction and metabolic deregulation are both associated with the HD but, despite multi-omics characterization of patients and model systems, their mechanisms have remained elusive. Systems analysis of multi-omics data and its validation by using a yeast model could help to elucidate pathways that modulate protein aggregation. Metabolomics analysis of HD patients and of a yeast model of HD was, therefore, carried out. Our analysis showed a considerable overlap of deregulated metabolic pathways. Further, the multi-omics analysis showed deregulated pathways common in human, mice and yeast model systems, and those that are unique to them. The deregulated pathways include metabolic pathways of various amino acids, glutathione metabolism, longevity, autophagy and mitophagy. The addition of certain metabolites as well as gene knockouts targeting the deregulated metabolic and autophagy pathways in the yeast model system showed that these pathways do modulate protein aggregation. Taken together, our results showed that the modulation of deregulated pathways influences protein aggregation in HD, and has implications for progression and prognosis. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Sai S. Pradhan
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Sai M. Thota
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Saiswaroop Rajaratnam
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Sai K. S. Bhagavatham
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Sujith K. Pulukool
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Sriram Rathnakumar
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Kanikaram S. Phalguna
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
| | - Rajesh B. Dandamudi
- Department of Chemistry, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh 515 134, India
| | - Ashish Pargaonkar
- Application Division, Agilent Technologies Ltd., Bengaluru 560048, India
| | - Prasanth Joseph
- Application Division, Agilent Technologies Ltd., Bengaluru 560048, India
| | - E. V. Joshy
- Department of Neurology, Sri Sathya Sai Institute of Higher Medical Sciences, Whitefield, Bengaluru, Karnataka 560066, India
| | - Venketesh Sivaramakrishnan
- Disease Biology Lab, Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Anantapur, Andhra Pradesh, India515134
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Piepgras J, Rohrbeck A, Just I, Bittner S, Ahnert-Hilger G, Höltje M. Enhancement of Phosphorylation and Transport Activity of the Neuronal Glutamate Transporter Excitatory Amino Acid Transporter 3 by C3bot and a 26mer C3bot Peptide. Front Cell Neurosci 2022; 16:860823. [PMID: 35783090 PMCID: PMC9240211 DOI: 10.3389/fncel.2022.860823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
In primary murine hippocampal neurons we investigated the regulation of EAAT3-mediated glutamate transport by the Clostridium botulinum C3 transferase C3bot and a 26mer peptide derived from full length protein. Incubation with either enzyme-competent C3bot or enzyme-deficient C3bot156–181 peptide resulted in the upregulation of glutamate uptake by up to 22% compared to untreated cells. A similar enhancement of glutamate transport was also achieved by the classical phorbol-ester-mediated activation of protein kinase C subtypes. Yet comparable, effects elicited by C3 preparations seemed not to rely on PKCα, γ, ε, or ζ activation. Blocking of tyrosine phosphorylation by tyrosine kinase inhibitors prevented the observed effect mediated by C3bot and C3bot 26mer. By using biochemical and molecular biological assays we could rule out that the observed C3bot and C3bot 26mer-mediated effects solely resulted from enhanced transporter expression or translocation to the neuronal surface but was rather mediated by transporter phosphorylation at tyrosine residues that was found to be significantly enhanced following incubation with either full length protein or the 26mer C3 peptide.
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Affiliation(s)
- Johannes Piepgras
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine-Main Neuroscience Network, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Astrid Rohrbeck
- Institute of Toxicology, Hannover Medical School, Hanover, Germany
| | - Ingo Just
- Institute of Toxicology, Hannover Medical School, Hanover, Germany
| | - Stefan Bittner
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine-Main Neuroscience Network, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Gudrun Ahnert-Hilger
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, University of Göttingen, Göttingen, Germany
| | - Markus Höltje
- Institut für Integrative Neuroanatomie, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- *Correspondence: Markus Höltje,
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4
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Mielnicka A, Michaluk P. Exocytosis in Astrocytes. Biomolecules 2021; 11:1367. [PMID: 34572580 PMCID: PMC8471187 DOI: 10.3390/biom11091367] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 12/17/2022] Open
Abstract
Until recently, astrocytes were thought to be a part of a simple "brain glue" providing only a supporting role for neurons. However, the discoveries of the last two decades have proven astrocytes to be dynamic partners participating in brain metabolism and actively influencing communication between neurons. The means of astrocyte-neuron communication are diverse, although regulated exocytosis has received the most attention but also caused the most debate. Similar to most of eukaryotic cells, astrocytes have a complex range of vesicular organelles which can undergo exocytosis as well as intricate molecular mechanisms that regulate this process. In this review, we focus on the components needed for regulated exocytosis to occur and summarise the knowledge about experimental evidence showing its presence in astrocytes.
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Affiliation(s)
| | - Piotr Michaluk
- BRAINCITY, Laboratory of Neurobiology, The Nencki Institute of Experimental Biology, PAS, 02-093 Warsaw, Poland;
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5
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Cocaine use disorder: A look at metabotropic glutamate receptors and glutamate transporters. Pharmacol Ther 2021; 221:107797. [DOI: 10.1016/j.pharmthera.2020.107797] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 11/04/2020] [Indexed: 01/08/2023]
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6
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Harre J, Heinkele L, Steffens M, Warnecke A, Lenarz T, Just I, Rohrbeck A. Potentiation of Brain-Derived Neurotrophic Factor-Induced Protection of Spiral Ganglion Neurons by C3 Exoenzyme/Rho Inhibitor. Front Cell Neurosci 2021; 15:602897. [PMID: 33776650 PMCID: PMC7991574 DOI: 10.3389/fncel.2021.602897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/19/2021] [Indexed: 11/17/2022] Open
Abstract
Preservation of the excitability of spiral ganglion neurons (SGN) may contribute to an improved speech perception after cochlear implantation. Thus, the application of exogenous neurotrophic factors such as the neurotrophin brain-derived neurotrophic factor (BDNF) to increase SGN survival in vitro and in vivo is a promising pharmacological approach in cochlear implant (CI) research. Due to the difficult pharmacokinetic profile of proteins such as BDNF, there is a quest for small molecules to mediate the survival of SGN or to increase the efficacy of BDNF. The C3 exoenzyme from Clostridium botulinum could be a potential new candidate for the protection and regeneration of SGN. Inhibition of the RhoA GTPase pathway which can be mediated by C3 is described as a promising strategy to enhance axonal regeneration and to exert pro-survival signals in neurons. Nanomolar concentrations of C3, its enzymatically inactive form C3E174Q, and a 26mer C-terminal peptide fragment covering amino acid 156–181 (C3156-181) potentiated the neuroprotective effect on SGN mediated by BDNF in vitro. The neuroprotective effect of C3/BDNF was reduced to the neuroprotective effect of BDNF alone after the treatment with wortmannin, an inhibitor of the phosphatidylinositol-3-kinase (PI3K).The exoenzyme C3 (wild-type and enzyme-deficient) and the C3 peptide fragment C3154–181 present novel biologically active compounds for the protection of the SGN. The exact underlying intracellular mechanisms that mediate the neuroprotective effect are not clarified yet, but the combination of BDNF (TrkB stimulation) and C3 exoenzyme (RhoA inhibition) can be used to protect SGN in vitro.
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Affiliation(s)
- Jennifer Harre
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 2177/1), Hannover, Germany
| | - Laura Heinkele
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Melanie Steffens
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 2177/1), Hannover, Germany
| | - Thomas Lenarz
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 2177/1), Hannover, Germany
| | - Ingo Just
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
| | - Astrid Rohrbeck
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
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7
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Adolf A, Rohrbeck A, Münster-Wandowski A, Johansson M, Kuhn HG, Kopp MA, Brommer B, Schwab JM, Just I, Ahnert-Hilger G, Höltje M. Release of astroglial vimentin by extracellular vesicles: Modulation of binding and internalization of C3 transferase in astrocytes and neurons. Glia 2018; 67:703-717. [PMID: 30485542 DOI: 10.1002/glia.23566] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/15/2018] [Accepted: 10/19/2018] [Indexed: 12/24/2022]
Abstract
Clostridium botulinum C3 transferase (C3bot) ADP-ribosylates rho proteins to change cellular functions in a variety of cell types including astrocytes and neurons. The intermediate filament protein vimentin as well as transmembrane integrins are involved in internalization of C3bot into cells. The exact contribution, however, of these proteins to binding of C3bot to the cell surface and subsequent cellular uptake remains to be unraveled. By comparing primary astrocyte cultures derived from wild-type with Vim-/- mice, we demonstrate that astrocytes lacking vimentin exhibited a delayed ADP-ribosylation of rhoA concurrent with a blunted morphological response. This functional impairment was rescued by the extracellular excess of recombinant vimentin. Binding assays using C3bot harboring a mutated integrin-binding RGD motif (C3bot-G89I) revealed the involvement of integrins in astrocyte binding of C3bot. Axonotrophic effects of C3bot are vimentin dependent and postulate an underlying mechanism entertaining a molecular cross-talk between astrocytes and neurons. We present functional evidence for astrocytic release of vimentin by exosomes using an in vitro scratch wound model. Exosomal vimentin+ particles released from wild-type astrocytes promote the interaction of C3bot with neuronal membranes. This effect vanished when culturing Vim-/- astrocytes. Specificity of these findings was confirmed by recombinant vimentin propagating enhanced binding of C3bot to synaptosomes from rat spinal cord and mouse brain. We hypothesize that vimentin+ exosomes released by reactive astrocytes provide a novel molecular mechanism constituting axonotrophic (neuroprotective) and plasticity augmenting effects of C3bot after spinal cord injury.
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Affiliation(s)
- Andrej Adolf
- Institute of Integrative Neuroanatomy, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Astrid Rohrbeck
- Institute of Toxicology, Hannover Medical School (MHH), Hanover, Germany
| | - Agnieszka Münster-Wandowski
- Institute of Integrative Neuroanatomy, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Malin Johansson
- Department of Clinical Neuroscience at Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden
| | - Hans-Georg Kuhn
- Department of Clinical Neuroscience at Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.,Department of Neurology and Experimental Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Marcel Alexander Kopp
- Department of Neurology and Experimental Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Berlin Institute of Health, QUEST - Center for Transforming Biomedical Research, Berlin, Germany
| | - Benedikt Brommer
- Department of Neurology and Experimental Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Jan Markus Schwab
- Department of Neurology and Experimental Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Paraplegiology (Spinal Cord Injury Division), Belford Spinal Cord Injury Center, Departments of Neurology, Neuroscience and Physical Medicine and Rehabilitation, The Neurological Institute, The Ohio State University, Wexner Medical Center, Columbus, Ohio
| | - Ingo Just
- Institute of Toxicology, Hannover Medical School (MHH), Hanover, Germany
| | - Gudrun Ahnert-Hilger
- Institute of Integrative Neuroanatomy, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Markus Höltje
- Institute of Integrative Neuroanatomy, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
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8
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Therapeutic use of botulinum toxin in pain treatment. Neuronal Signal 2018; 2:NS20180058. [PMID: 32714587 PMCID: PMC7373233 DOI: 10.1042/ns20180058] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 05/22/2018] [Accepted: 06/25/2018] [Indexed: 11/17/2022] Open
Abstract
Botulinum toxin is one of the most potent molecule known to mankind. A neurotoxin, with high affinity for cholinergic synapse, is effectively capable of inhibiting the release of acetylcholine. On the other hand, botulinum toxin is therapeutically used for several musculoskeletal disorders. Although most of the therapeutic effect of botulinum toxin is due to temporary skeletal muscle relaxation (mainly due to inhibition of the acetylcholine release), other effects on the nervous system are also investigated. One of the therapeutically investigated areas of the botulinum neurotoxin (BoNT) is the treatment of pain. At present, it is used for several chronic pain diseases, such as myofascial syndrome, headaches, arthritis, and neuropathic pain. Although the effect of botulinum toxin in pain is mainly due to its effect on cholinergic transmission in the somatic and autonomic nervous systems, research suggests that botulinum toxin can also provide benefits related to effects on cholinergic control of cholinergic nociceptive and antinociceptive systems. Furthermore, evidence suggests that botulinum toxin can also affect central nervous system (CNS). In summary, botulinum toxin holds great potential for pain treatments. It may be also useful for the pain treatments where other methods are ineffective with no side effect(s). Further studies will establish the exact analgesic mechanisms, efficacy, and complication of botulinum toxin in chronic pain disorders, and to some extent acute pain disorders.
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9
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Bohmbach K, Schwarz MK, Schoch S, Henneberger C. The structural and functional evidence for vesicular release from astrocytes in situ. Brain Res Bull 2017; 136:65-75. [PMID: 28122264 DOI: 10.1016/j.brainresbull.2017.01.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/17/2017] [Accepted: 01/19/2017] [Indexed: 12/31/2022]
Abstract
The concept of the tripartite synapse states that bi-directional signalling between perisynaptic astrocyte processes, presynaptic axonal boutons and postsynaptic neuronal structures defines the properties of synaptic information processing. Ca2+-dependent vesicular release from astrocytes, as one of the mechanisms of astrocyte-neuron communication, has attracted particular attention but has also been the subject of intense debate. In neurons, regulated vesicular release is a strongly coordinated process. It requires a complex release machinery comprised of many individual components ranging from vesicular neurotransmitter transporters and soluble NSF attachment protein receptors (SNARE) proteins to Ca2+-sensors and the proteins that spatially and temporally control exocytosis of synaptic vesicles. If astrocytes employ similar mechanisms to release neurotransmitters is less well understood. The aim of this review is therefore to discuss recent experimental evidence that sheds light on the central structural components responsible for vesicular release from astrocytes in situ.
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Affiliation(s)
- Kirsten Bohmbach
- Institute of Cellular Neurosciences, University of Bonn Medical School, Bonn, Germany.
| | - Martin K Schwarz
- Department of Epileptology, University of Bonn Medical School, Bonn, Germany
| | - Susanne Schoch
- Institute of Neuropathology, University of Bonn Medical School, Bonn, Germany
| | - Christian Henneberger
- Institute of Cellular Neurosciences, University of Bonn Medical School, Bonn, Germany; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Institute of Neurology, University College London, London, United Kingdom.
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10
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Nguyen LS, Lepleux M, Makhlouf M, Martin C, Fregeac J, Siquier-Pernet K, Philippe A, Feron F, Gepner B, Rougeulle C, Humeau Y, Colleaux L. Profiling olfactory stem cells from living patients identifies miRNAs relevant for autism pathophysiology. Mol Autism 2016; 7:1. [PMID: 26753090 PMCID: PMC4705753 DOI: 10.1186/s13229-015-0064-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 12/21/2015] [Indexed: 01/09/2023] Open
Abstract
Background Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders caused by the interaction between genetic vulnerability and environmental factors. MicroRNAs (miRNAs) are key posttranscriptional regulators involved in multiple aspects of brain development and function. Previous studies have investigated miRNAs expression in ASD using non-neural cells like lymphoblastoid cell lines (LCL) or postmortem tissues. However, the relevance of LCLs is questionable in the context of a neurodevelopmental disorder, and the impact of the cause of death and/or post-death handling of tissue likely contributes to the variations observed between studies on brain samples. Methods miRNA profiling using TLDA high-throughput real-time qPCR was performed on miRNAs extracted from olfactory mucosal stem cells (OMSCs) biopsied from eight patients and six controls. This tissue is considered as a closer tissue to neural stem cells that could be sampled in living patients and was never investigated for such a purpose before. Real-time PCR was used to validate a set of differentially expressed miRNAs, and bioinformatics analysis determined common pathways and gene targets. Luciferase assays and real-time PCR analysis were used to evaluate the effect of miRNAs misregulation on the expression and translation of several autism-related transcripts. Viral vector-mediated expression was used to evaluate the impact of miRNAs deregulation on neuronal or glial cells functions. Results We identified a signature of four miRNAs (miR-146a, miR-221, miR-654-5p, and miR-656) commonly deregulated in ASD. This signature is conserved in primary skin fibroblasts and may allow discriminating between ASD and intellectual disability samples. Putative target genes of the differentially expressed miRNAs were enriched for pathways previously associated to ASD, and altered levels of neuronal transcripts targeted by miR-146a, miR-221, and miR-656 were observed in patients’ cells. In the mouse brain, miR-146a, and miR-221 display strong neuronal expression in regions important for high cognitive functions, and we demonstrated that reproducing abnormal miR-146a expression in mouse primary cell cultures leads to impaired neuronal dendritic arborization and increased astrocyte glutamate uptake capacities. Conclusions While independent replication experiments are needed to clarify whether these four miRNAS could serve as early biomarkers of ASD, these findings may have important diagnostic implications. They also provide mechanistic connection between miRNA dysregulation and ASD pathophysiology and may open up new opportunities for therapeutic. Electronic supplementary material The online version of this article (doi:10.1186/s13229-015-0064-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lam Son Nguyen
- INSERM UMR 1163, Laboratory of Molecular and pathophysiological bases of cognitive disorders, Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, 24 boulevard du Montparnasse, 75015 Paris, France
| | - Marylin Lepleux
- Synapse in Cognition Laboratory, Institut Interdisciplinaire de NeuroSciences, Centre de génomique fonctionnelle, UMR 5297 CNRS - Université de Bordeaux, 146 rue Léo Saignat, 33077 Bordeaux, France
| | - Mélanie Makhlouf
- Epigénétique et Destin Cellulaire, Université Paris Diderot, UMR 7216, 75205 Paris, France
| | - Christelle Martin
- Synapse in Cognition Laboratory, Institut Interdisciplinaire de NeuroSciences, Centre de génomique fonctionnelle, UMR 5297 CNRS - Université de Bordeaux, 146 rue Léo Saignat, 33077 Bordeaux, France
| | - Julien Fregeac
- INSERM UMR 1163, Laboratory of Molecular and pathophysiological bases of cognitive disorders, Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, 24 boulevard du Montparnasse, 75015 Paris, France
| | - Karine Siquier-Pernet
- INSERM UMR 1163, Laboratory of Molecular and pathophysiological bases of cognitive disorders, Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, 24 boulevard du Montparnasse, 75015 Paris, France
| | - Anne Philippe
- INSERM UMR 1163, Laboratory of Molecular and pathophysiological bases of cognitive disorders, Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, 24 boulevard du Montparnasse, 75015 Paris, France
| | - François Feron
- Aix Marseille Université, NICN, CNRS UMR 7259, 13344 Marseille, France
| | - Bruno Gepner
- Aix Marseille Université, NICN, CNRS UMR 7259, 13344 Marseille, France
| | - Claire Rougeulle
- Epigénétique et Destin Cellulaire, Université Paris Diderot, UMR 7216, 75205 Paris, France
| | - Yann Humeau
- Synapse in Cognition Laboratory, Institut Interdisciplinaire de NeuroSciences, Centre de génomique fonctionnelle, UMR 5297 CNRS - Université de Bordeaux, 146 rue Léo Saignat, 33077 Bordeaux, France
| | - Laurence Colleaux
- INSERM UMR 1163, Laboratory of Molecular and pathophysiological bases of cognitive disorders, Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, 24 boulevard du Montparnasse, 75015 Paris, France
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Targeting glutamate homeostasis for potential treatment of nicotine dependence. Brain Res Bull 2015; 121:1-8. [PMID: 26589642 DOI: 10.1016/j.brainresbull.2015.11.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/06/2015] [Accepted: 11/09/2015] [Indexed: 01/06/2023]
Abstract
Several studies demonstrated that impairment in glutamatergic neurotransmission is linked to drug dependence and drug-seeking behavior. Increased extracellular glutamate concentration in mesocorticolimbic regions has been observed in animals developing nicotine dependence. Changes in glutamate release might be associated with stimulatory effect of nicotinic acetylcholine receptors (nAChRs) via nicotine exposure. We and others have shown increased extracellular glutamate concentration, which was associated with down regulation of the major glutamate transporter, glutamate transporter 1 (GLT-1), in brain reward regions of animals exposed to drug abuse, including nicotine and ethanol. Importantly, studies from our laboratory and others showed that upregulation of GLT-1 expression in the mesocorticolimbic brain regions may have potential therapeutic effects in drug dependence. In this review article, we discussed the effect of antagonizing presynaptic nAChRs in glutamate release, the upregulatory effect in GLT-1 expression and the role of glutamate receptors antagonists in the treatment of nicotine dependence.
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12
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Rohrbeck A, Stahl F, Höltje M, Hettwer T, Lindner P, Hagemann S, Pich A, Haastert-Talini K. C3-induced release of neurotrophic factors from Schwann cells - potential mechanism behind its regeneration promoting activity. Neurochem Int 2015; 90:232-45. [PMID: 26417907 DOI: 10.1016/j.neuint.2015.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/11/2015] [Accepted: 09/23/2015] [Indexed: 01/10/2023]
Abstract
Previous studies revealed a peripheral nerve regeneration (PNR)(1) promoting activity of Clostridium botulinum C3(2) exoenzyme or a 26(mer) C-terminal peptide fragment covering amino acids 156-181 (C3(156-181)),(3) when delivered as one-time injection at the lesion site. The current study was performed to 1) investigate if prolonged availability of C3 and C3(156-181) at the lesion site can further enhance PNR in vivo and to 2) elucidate effects of C3 and C3(156-181) on Schwann cells (SCs)(4)in vitro. For in vivo studies, 10 mm adult rat sciatic nerve gaps were reconstructed with the epineurial pouch technique or autologous nerve grafts. Epineurial pouches were filled with a hydrogel containing i) vehicle, ii) 40 μM C3 or iii) 40 μM C3(156-181). Sensory and motor functional recovery was monitored over 12 weeks and the outcome of PNR further analyzed by nerve morphometry. In vitro, we compared gene expression profiles (microarray analysis) and neurotrophic factor expression (western blot analysis) of untreated rat neonatal SCs with those treated with C3 or C3(156-181) for 72 h. Effects on neurotrophic factor expression levels were proven in adult human SCs. Unexpectedly, prolonged delivery of C3 and C3(156-181) at the lesion site did not increase the outcome of PNR. Regarding the potential mechanism underlying their previously detected PNR promoting action, however, 6 genes were found to be commonly altered in SCs upon treatment with C3 or C3(156-181). We demonstrate significant down-regulation of genes involved in glutamate uptake (Eaac1,(5)Grin2a(6)) and changes in neurotrophic factor expression (increase of FGF-2(7) and decrease of NGF(8)). Our microarray-based expression profiling revealed novel C3-regulated genes in SCs possibly involved in the axonotrophic (regeneration promoting) effects of C3 and C3(156-181). Detection of altered neurotrophic factor expression by C3 or C3(156-181) treated primary neonatal rat SCs and primary adult human SCs supports this hypothesis.
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Affiliation(s)
- Astrid Rohrbeck
- Institute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.
| | - Frank Stahl
- Institute for Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, D-30167 Hannover, Germany
| | - Markus Höltje
- Institute for Integrative Neuroanatomy, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Timo Hettwer
- Institute of Neuroanatomy, Hannover Medical School and Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Patrick Lindner
- Institute for Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, D-30167 Hannover, Germany
| | - Sandra Hagemann
- Institute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Andreas Pich
- Institute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Kirsten Haastert-Talini
- Institute of Neuroanatomy, Hannover Medical School and Carl-Neuberg-Str. 1, D-30625 Hannover, Germany; Center for Systems Neuroscience (ZSN), Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.
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13
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Abstract
Neuroglia, the "glue" that fills the space between neurons in the central nervous system, takes active part in nerve cell signaling. Neuroglial cells, astroglia, oligodendroglia, and microglia, are together about as numerous as neurons in the brain as a whole, and in the cerebral cortex grey matter, but the proportion varies widely among brain regions. Glial volume, however, is less than one-fifth of the tissue volume in grey matter. When stimulated by neurons or other cells, neuroglial cells release gliotransmitters by exocytosis, similar to neurotransmitter release from nerve endings, or by carrier-mediated transport or channel flux through the plasma membrane. Gliotransmitters include the common neurotransmitters glutamate and GABA, the nonstandard amino acid d-serine, the high-energy phosphate ATP, and l-lactate. The latter molecule is a "buffer" between glycolytic and oxidative metabolism as well as a signaling substance recently shown to act on specific lactate receptors in the brain. Complementing neurotransmission at a synapse, neuroglial transmission often implies diffusion of the transmitter over a longer distance and concurs with the concept of volume transmission. Transmission from glia modulates synaptic neurotransmission based on energetic and other local conditions in a volume of tissue surrounding the individual synapse. Neuroglial transmission appears to contribute significantly to brain functions such as memory, as well as to prevalent neuropathologies.
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Affiliation(s)
- Vidar Gundersen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Jon Storm-Mathisen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Linda Hildegard Bergersen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
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14
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Ashpole NM, Chawla AR, Martin MP, Brustovetsky T, Brustovetsky N, Hudmon A. Loss of calcium/calmodulin-dependent protein kinase II activity in cortical astrocytes decreases glutamate uptake and induces neurotoxic release of ATP. J Biol Chem 2013; 288:14599-14611. [PMID: 23543737 DOI: 10.1074/jbc.m113.466235] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The extent of calcium/calmodulin-dependent protein kinase II (CaMKII) inactivation in the brain after ischemia correlates with the extent of damage. We have previously shown that a loss of CaMKII activity in neurons is detrimental to neuronal viability by inducing excitotoxic glutamate release. In the current study we extend these findings to show that the ability of astrocytes to buffer extracellular glutamate is reduced when CaMKII is inhibited. Furthermore, CaMKII inhibition in astrocytes is associated with the rapid onset of intracellular calcium oscillations. Surprisingly, this rapid calcium influx is blocked by the N-type calcium channel antagonist, ω-conotoxin. Although the function of N-type calcium channels within astrocytes is controversial, these voltage-gated calcium channels have been linked to calcium-dependent vesicular gliotransmitter release. When extracellular glutamate and ATP levels are measured after CaMKII inhibition within our enriched astrocyte cultures, no alterations in glutamate levels are observed, whereas ATP levels in the extracellular environment significantly increase. Extracellular ATP accumulation associated with CaMKII inhibition contributes both to calcium oscillations within astrocytes and ultimately cortical neuron toxicity. Thus, a loss of CaMKII signaling within astrocytes dysregulates glutamate uptake and supports ATP release, two processes that would compromise neuronal survival after ischemic/excitotoxic insults.
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Affiliation(s)
- Nicole M Ashpole
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Aarti R Chawla
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Matthew P Martin
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Tatiana Brustovetsky
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Nickolay Brustovetsky
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Andy Hudmon
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
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15
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Abstract
Background: Two decades ago, botulinum neurotoxin (BoNT) type A was introduced to the commercial market. Subsequently, the toxin was approved by the FDA to address several neurological syndromes, involving muscle, nerve, and gland hyperactivity. These syndromes have typically been associated with abnormalities in cholinergic transmission. Despite the multiplicity of botulinal serotypes (designated as types A through G), therapeutic preparations are currently only available for BoNT types A and B. However, other BoNT serotypes are under study for possible clinical use and new clinical indications; Objective: To review the current research on botulinum neurotoxin serotypes A-G, and to analyze potential applications within basic science and clinical settings; Conclusions: The increasing understanding of botulinal neurotoxin pathophysiology, including the neurotoxin’s effects on specific neuronal populations, will help us in tailoring treatments for specific diagnoses, symptoms and patients. Scientists and clinicians should be aware of the full range of available data involving neurotoxin subtypes A-G.
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16
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Otsuka S, Adamson C, Sankar V, Gibbs KM, Kane-Goldsmith N, Ayer J, Babiarz J, Kalinski H, Ashush H, Alpert E, Lahav R, Feinstein E, Grumet M. Delayed intrathecal delivery of RhoA siRNA to the contused spinal cord inhibits allodynia, preserves white matter, and increases serotonergic fiber growth. J Neurotrauma 2012; 28:1063-76. [PMID: 21443453 DOI: 10.1089/neu.2010.1568] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
RhoA is a key regulator of the actin cytoskeleton that is upregulated after spinal cord injury (SCI). We analyzed different methods for siRNA delivery and developed siRNAs targeting RhoA (siRhoA) for SCI treatment. Cy 3.5-labeled siRNA delivered at the time of SCI yielded fluorescence in several cell types in the injury site. Intraspinal injections of chemically stabilized siRhoA into the spinal cord of injured rats reduced RhoA protein levels after 1 week and improved hindlimb walking over 6 weeks. To explore a less invasive route, we tested intrathecal injection of Cy 3.5-labeled siRNA via lumbar puncture 1 day after SCI, which resulted in robust uptake in the T9-T10 injury site. Lumbar injection of siRhoA 1 day after SCI reduced RhoA mRNA and protein levels 3 days after injection. Although siRhoA treatment did not yield significant improvement in locomotion, it decreased tactile hypersensitivity significantly compared to controls. Histological analysis at 8 weeks showed significant improvement in white matter sparing with siRhoA compared to control siRNA. siRhoA treatment also resulted in less accumulation of ED1+macrophages, increased PKC-γ immunoreactivity in the corticospinal tract rostral to the injury site, and increased serotonergic fiber growth 12 mm caudal to the contusion site. The ability of siRhoA to preserve white matter and promote serotonergic axonal regrowth caudal to the injury site is likely to suppress allodynia. This provides justification for considering clinical development of RhoA inhibitors to treat SCI sub-acutely to reduce allodynia, which occurs frequently in SCI patients.
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Affiliation(s)
- Seiji Otsuka
- W.M. Keck Center for Collaborative Neuroscience, Rutgers Stem Cell Research Center, Department of Cell Biology & Neuroscience, Rutgers, State University of New Jersey, Piscataway, New Jersey 08854-8082, USA
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17
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Ormel L, Stensrud MJ, Chaudhry FA, Gundersen V. A distinct set of synaptic-like microvesicles in atroglial cells contain VGLUT3. Glia 2012; 60:1289-300. [DOI: 10.1002/glia.22348] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 04/13/2012] [Indexed: 11/09/2022]
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18
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Abstract
Protocols are presented describing a unique in vitro injury model and how to culture and mature mouse, rat, and human astrocytes for its use. This injury model produces widespread injury and astrocyte reactivity that enable quantitative measurements of morphological, biochemical, and functional changes in rodent and human reactive astrocytes. To investigate structural and molecular mechanisms of reactivity in vitro, cultured astrocytes need to be purified and then in vitro "matured" to reach a highly differentiated state. This is achieved by culturing astrocytes on deformable collagen-coated membranes in the presence of adult-derived horse serum (HS), followed by its stepwise withdrawal. These in vitro matured, process-bearing, quiescent astrocytes are then subjected to mechanical stretch injury by an abrupt pressure pulse from a pressure control device that briefly deforms the culture well bottom. This inflicts a measured reproducible, widespread strain that induces reactivity and injury in rodent and human astrocytes. Cross-species comparisons are possible because mouse, rat, and human astrocytes are grown using essentially the same in vitro treatment regimen. Human astrocytes from fetal cerebral cortex are compared to those derived from cortical biopsies of epilepsy patients (ages 1-12 years old), with regard to growth, purity, and differentiation. This opens a unique opportunity for future studies on glial biology, maturation, and pathology of human astrocytes. Prototypical astrocyte proteins including GFAP, S100, aquaporin4, glutamate transporters, and tenascin are expressed in mouse, rat, and human in vitro matured astrocyte. Upon pressure-stretching, rodent and human astrocytes undergo dynamic morphological, gene expression, and protein changes that are characteristic for trauma-induced reactive astrogliosis.
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Affiliation(s)
- Ina-Beate Wanner
- Semel Institute for Neuroscience and Human Behavior, UCLA, Los Angeles, CA, USA.
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19
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Huelsenbeck SC, Rohrbeck A, Handreck A, Hellmich G, Kiaei E, Roettinger I, Grothe C, Just I, Haastert-Talini K. C3 peptide promotes axonal regeneration and functional motor recovery after peripheral nerve injury. Neurotherapeutics 2012; 9:185-98. [PMID: 21866396 PMCID: PMC3271155 DOI: 10.1007/s13311-011-0072-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Peripheral nerve injuries are frequently seen in trauma patients and due to delayed nerve repair, lifelong disabilities often follow this type of injury. Innovative therapies are needed to facilitate and expedite peripheral nerve regeneration. The purpose of this study was to determine the effects of a 1-time topical application of a 26-amino-acid fragment (C3(156-181)), derived from the Clostridium botulinum C3-exoenzyme, on peripheral nerve regeneration in 2 models of nerve injury and repair in adult rats. After sciatic nerve crush, different dosages of C3(156-181) dissolved in buffer or reference solutions (nerve growth factor or C3(bot)-wild-type protein) or vehicle-only were injected through an epineurial opening into the lesion sites. After 10-mm nerve autotransplantation, either 8.0 nmol/kg C3(156-181) or vehicle were injected into the proximal and distal suture sites. For a period of 3 to 10 postoperative weeks, C3(156-181)-treated animals showed a faster motor recovery than control animals. After crush injury, axonal outgrowth and elongation were activated and consequently resulted in faster motor recovery. The nerve autotransplantation model further elucidated that C3(156-181) treatment accounts for better axonal elongation into motor targets and reduced axonal sprouting, which are followed by enhanced axonal maturation and better axonal functionality. The effects of C3(156-181) are likely caused by a nonenzymatic down-regulation of active RhoA. Our results indicate the potential of C3(156-181) as a therapeutic agent for the topical treatment of peripheral nerve repair sites.
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Affiliation(s)
- Stefanie C. Huelsenbeck
- Hannover Medical School, Institute of Toxicology, Hannover, 30625 Germany
- Present Address: Institute of Toxicology, University Medical Center of the Johannes-Gutenberg-University Mainz, Mainz, 55131 Germany
| | - Astrid Rohrbeck
- Hannover Medical School, Institute of Toxicology, Hannover, 30625 Germany
| | - Annelie Handreck
- Hannover Medical School, Institute of Neuroanatomy, Hannover, 30625 Germany
| | - Gesa Hellmich
- Hannover Medical School, Institute of Neuroanatomy, Hannover, 30625 Germany
| | - Eghlima Kiaei
- Hannover Medical School, Institute of Neuroanatomy, Hannover, 30625 Germany
| | - Irene Roettinger
- Hannover Medical School, Institute of Neuroanatomy, Hannover, 30625 Germany
| | - Claudia Grothe
- Hannover Medical School, Institute of Neuroanatomy, Hannover, 30625 Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Ingo Just
- Hannover Medical School, Institute of Toxicology, Hannover, 30625 Germany
| | - Kirsten Haastert-Talini
- Hannover Medical School, Institute of Neuroanatomy, Hannover, 30625 Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
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20
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Piovesan EJ, Leite LDS, Teive HG, Kowacs PA, Mulinari RA, Radunz V, Utiumi M, Campos HG, Werneck LC. Botulinum toxin type-A effect as a preemptive treatment in a model of acute trigeminal pain: a pre-clinical double-blind and placebo-controlled study. ARQUIVOS DE NEURO-PSIQUIATRIA 2011; 69:56-63. [PMID: 21359424 DOI: 10.1590/s0004-282x2011000100012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Accepted: 08/17/2010] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to investigate if botulinum neurotoxin type-A (BoNT/A) had a preemptive antinociceptive effect in a formalin-induced orofacial pain model (FT). To test this hypothesis, male Rattus norvegicus were injected with isotonic saline solution 0.9% or BoNT/A administered as a 40 μl bolus, lateral to their nose, at 24 hours, 8, 15, 22, 29 or 36 days pre-FT. The procedures were repeated 42 days later. Influence on motor activity was assessed through the open-field test. Pain scores corresponded to the time spent rubbing and flicking the injected area. Animals pre-treated with BoNT/A at the first protocol (8 days subgroup) showed reduced inflammatory scores (p=0.011). For the other groups no significant results were observed at any phase. Motor activity was similar in both groups. BoNT/A showed to be effective preventing inflammatory pain up to eight days after the first treatment, an effect not reproduced on the second dose administration.
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Affiliation(s)
- Elcio Juliato Piovesan
- Unit of Headache, Neurology Division, Internal Medicine Department, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba PR, Brazil.
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21
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Razafimanjato H, Benzaria A, Taïeb N, Guo XJ, Vidal N, Di Scala C, Varini K, Maresca M. The ribotoxin deoxynivalenol affects the viability and functions of glial cells. Glia 2011; 59:1672-83. [PMID: 21748807 DOI: 10.1002/glia.21214] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 06/16/2011] [Indexed: 11/08/2022]
Abstract
Glial cells are responsible for maintaining brain homeostasis. Modification of the viability and functions of glial cells, including astrocytes and microglia, are associated with neuronal death and neurological diseases. Many toxins (heavy metals, pesticides, bacterial or viral toxins) are known to impact on brain cell viability and functions. Although recent publications suggest a potential link between environmental exposure of humans to mycotoxins and neurological diseases, data regarding the effects of fungal toxins on brain cells are scarce. In the present study, we looked at the impact of deoxynivalenol (DON), a fungal ribotoxin, on glial cells from animal and human origin. We found that DON decreased the viability of glial cells with a higher toxicity against microglial cells compared with astrocytes. In addition to cellular toxicity, DON affected key functions of glial cells. Thus, DON caused a biphasic effect on the neuroinflammatory response of microglia to lipopolysaccharide (LPS), while sublethal doses of DON increased the LPS-induced secretion of TNF-α and nitric oxide, toxic doses inhibited it. In addition to affecting microglial functions, sublethal doses of DON also suppressed the uptake of L-glutamate by astrocytes. This inhibition was associated with a modification of the expression of the glutamate transporters at the plasma membrane. Our results suggest that environmental ribotoxins such as DON could, at low doses, cause modifications of brain homeostasis and possibly participate in the etiology of neurological diseases in which alterations of the glia are involved.
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Affiliation(s)
- Helisoa Razafimanjato
- CRN2M, CNRS UMR 6231, INRA USC 2027, University of Aix-Marseille 2 and Aix-Marseille 3, Faculté des Sciences de St-Jérôme, 13397 Marseille Cedex 20, France
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22
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Clostridial C3 proteins: Recent approaches to improve neuronal growth and regeneration. Ann Anat 2011; 193:314-20. [DOI: 10.1016/j.aanat.2011.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 01/11/2011] [Accepted: 01/11/2011] [Indexed: 12/13/2022]
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23
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Hodges RR, Guilbert E, Shatos MA, Natarajan V, Dartt DA. Phospholipase D1, but not D2, regulates protein secretion via Rho/ROCK in a Ras/Raf-independent, MEK-dependent manner in rat lacrimal gland. Invest Ophthalmol Vis Sci 2011; 52:2199-210. [PMID: 21212180 DOI: 10.1167/iovs.10-6209] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE A prior study showed that cholinergic agonists activate phospholipase D (PLD). The purpose of this study was to determine whether cholinergic agonists use the PLD pathway to alter protein secretion and to identify the molecular signaling components of this pathway in rat lacrimal gland acini. METHODS Rat lacrimal gland acini were isolated by collagenase digestion. Presence and localization of PLD1 and -2 were determined by immunofluorescence and Western blot experiments. Acini were incubated with adenoviruses overnight or the inhibitors 1-butanol, Y-27632, or C3 exotoxin before stimulation with the cholinergic agonist carbachol (Cch, 10(-4) M) for 5 minutes. Western blot analysis was performed for 20 minutes, and protein secretion was measured spectrophotometrically. Activation of ERK, MEK, Pyk2, Ras, and Raf was determined by Western blot analysis. RESULTS 1-Butanol increased Cch-stimulated protein secretion and decreased ERK activity. Incubation with catalytically inactive PLD1, but not catalytically inactive mutant PLD2 adenovirus, also increased Cch-stimulated protein secretion and decreased ERK activity. Inhibition of Rho with C3 exotoxin and a dominant negative Rho adenovirus and inhibition of ROCK with Y-27632 inhibited Cch-stimulated PLD1 activity, increased protein secretion, and decreased ERK activity. The association of PLD1 and ROCK increased with Cch stimulation, as determined by immunoprecipitation. PMA-stimulated ERK activity was also inhibited by 1-butanol. 1-Butanol had no effect on Cch-stimulated Pyk2, Ras, and Raf activity, but decreased MEK activity. CONCLUSIONS Cholinergic agonists activate PLD1 through Rho and ROCK, which in turn activate MEK and ERK, which attenuate protein secretion in freshly isolated epithelial cells.
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Affiliation(s)
- Robin R Hodges
- Schepens Eye Research Institute, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA.
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24
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Just I, Rohrbeck A, Huelsenbeck SC, Hoeltje M. Therapeutic effects of Clostridium botulinum C3 exoenzyme. Naunyn Schmiedebergs Arch Pharmacol 2010; 383:247-52. [PMID: 21193903 DOI: 10.1007/s00210-010-0589-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 12/12/2010] [Indexed: 12/17/2022]
Abstract
C3 exoenzyme from Clostridium botulinum, specifically ADP-ribosylates small GTP-binding proteins RhoA, B, and C. ADP-ribosylation causes functional inactivation of Rho proteins resulting in cessation of the complete downstream signaling. Rho proteins are general regulators of a lot of essential cellular functions, among others, the neuronal growth cone. Rho activation, triggered by neuronal injury, inhibits neuronal repair mechanisms. To prevent the detrimental effect of active Rho in the recovery of injured neuronal systems, C3 has become a promising drug to inactivate RhoA in neurons. During the advancement of C3 to a drug candidate, it was found that ADP-ribosyltransferase activity of C3, in fact, is not essential for axonal and dendritic growth and branching. Rather, a peptide fragment of C3 covering the surface exposed ARTT loop from C3 (C3(154-182) peptide) is sufficient to induce growth and branching of neurons comparable to the effect of full-length C3. Whereas full-length C3 also acts on astrocytes and microglia to induce-at least in an in vitro model-inflammation and glial scar formation, C3(154-182) peptide is inert and seems only to act on neurons. In addition to its axono- and dendritotrophic effects on cultured primary hippocampal neurons, C3(154-182) peptide enhanced functional recovery and regeneration in a mouse model of spinal cord injury. Thus, in a proof-of-principle experiment, C3 peptide was shown to be efficacious in post-traumatic neuro-regeneration.
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Affiliation(s)
- Ingo Just
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30625 Hannover, Germany.
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25
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Boato F, Hendrix S, Huelsenbeck SC, Hofmann F, Große G, Djalali S, Klimaschewski L, Auer M, Just I, Ahnert-Hilger G, Höltje M. C3 peptide enhances recovery from spinal cord injury by improved regenerative growth of descending fiber tracts. J Cell Sci 2010; 123:1652-62. [DOI: 10.1242/jcs.066050] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Functional recovery and regeneration of corticospinal tract (CST) fibers following spinal cord injury by compression or dorsal hemisection in mice was monitored after application of the enzyme-deficient Clostridium botulinum C3-protein-derived 29-amino-acid fragment C3bot154-182. This peptide significantly improved locomotor restoration in both injury models as assessed by the open-field Basso Mouse Scale for locomotion test and Rotarod treadmill experiments. These data were supported by tracing studies showing an enhanced regenerative growth of CST fibers in treated animals as visualized by anterograde tracing. Additionally, C3bot154-182 stimulated regenerative growth of raphespinal fibers and improved serotonergic input to lumbar α-motoneurons. These in vivo data were confirmed by in vitro data, showing an enhanced axon outgrowth of α-motoneurons and hippocampal neurons cultivated on normal or growth-inhibitory substrates after application of C3bot154-182. The observed effects were probably caused by a non-enzymatic downregulation of active RhoA by the C3 peptide as indicated by pull-down experiments. By contrast, C3bot154-182 did not induce neurite outgrowth in primary cultures of dorsal root ganglion cells. In conclusion, C3bot154-182 represents a novel, promising tool to foster axonal protection and/or repair, as well as functional recovery after traumatic CNS injury.
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Affiliation(s)
- Francesco Boato
- Center for Anatomy, Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Sven Hendrix
- Center for Anatomy, Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
- Department of Morphology and BIOMED Institute, Hasselt University, Agoralaangebouw A, B-3590 Diepenbeek, Belgium
| | - Stefanie C. Huelsenbeck
- Institute of Toxicology, Hannover Medical School (MHH), Carl-Neuberg-Straße 1, D-30625 Hannover, Germany
| | - Fred Hofmann
- Institute of Toxicology, Hannover Medical School (MHH), Carl-Neuberg-Straße 1, D-30625 Hannover, Germany
| | - Gisela Große
- Center for Anatomy, Functional Cell Biology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Susann Djalali
- Center for Anatomy, Functional Cell Biology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Lars Klimaschewski
- Division of Neuroanatomy, Department of Anatomy, Histology and Embryology, Innsbruck Medical University, Müllerstraße 59, A-6020 Innsbruck, Austria
| | - Maria Auer
- Division of Neuroanatomy, Department of Anatomy, Histology and Embryology, Innsbruck Medical University, Müllerstraße 59, A-6020 Innsbruck, Austria
| | - Ingo Just
- Institute of Toxicology, Hannover Medical School (MHH), Carl-Neuberg-Straße 1, D-30625 Hannover, Germany
| | - Gudrun Ahnert-Hilger
- Center for Anatomy, Functional Cell Biology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Markus Höltje
- Center for Anatomy, Functional Cell Biology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
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Hayashida KI, Parker RA, Eisenach JC. Activation of glutamate transporters in the locus coeruleus paradoxically activates descending inhibition in rats. Brain Res 2010; 1317:80-6. [PMID: 20059984 DOI: 10.1016/j.brainres.2009.12.086] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 12/15/2009] [Accepted: 12/29/2009] [Indexed: 02/01/2023]
Abstract
Descending noradrenergic inhibition is an important endogenous pain-relief mechanism which can be activated by local glutamate signaling. In the present study, we examined the effect of glutamate transporter activation by riluzole in the regulation of activity of locus coeruleus (LC) neurons, which provide the major inhibitory descending noradrenergic projection to the spinal cord. Local injection of riluzole into the LC dose-dependently reduced hypersensitivity in rats after L5-L6 spinal nerve ligation (SNL). This anti-hypersensitivity effect of LC-injected riluzole was blocked by intrathecal administration of the alpha2-adrenoceptor antagonist idazoxan and intra-LC co-injection of the AMPA antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and the gap-junction blockers, carbenoxolone (CBX) and meclofenamic acid (MEC). In brainstem slices from normal rats, riluzole increased phosphorylated cAMP response element binding protein (pCREB) expressing nuclei in dopamine-beta-hydroxylase (DbetaH) containing cells in the LC. This riluzole-induced pCREB activation in LC neurons was also blocked by CNQX and CBX. In the primary astrocyte culture, riluzole enhanced glutamate-induced glutamate release. Contrary to expectations, these results suggest that activation of glutamate transporters in the LC results in increase of extracellular glutamate signaling, possibly via facilitation of glutamate release from astrocytes, and activation of LC neurons to induce descending inhibition, and that this paradoxical action of glutamate transporters in the LC requires gap-junction connections.
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Affiliation(s)
- Ken-ichiro Hayashida
- Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston Salem, NC 27157-1009, USA.
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27
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Jiang M, Bajpayee NS. Molecular mechanisms of go signaling. Neurosignals 2009; 17:23-41. [PMID: 19212138 DOI: 10.1159/000186688] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 04/09/2008] [Indexed: 12/26/2022] Open
Abstract
Go is the most abundant G protein in the central nervous system, where it comprises about 1% of membrane protein in mammalian brains. It functions to couple cell surface receptors to intercellular effectors, which is a critical process for cells to receive, interpret and respond to extracellular signals. Go protein belongs to the pertussis toxin-sensitive Gi/Go subfamily of G proteins. A number of G-protein-coupled receptors transmit stimuli to intercellular effectors through Go. Go regulates several cellular effectors, including ion channels, enzymes, and even small GTPases to modulate cellular function. This review summarizes some of the advances in Go research and proposes areas to be further addressed in exploring the functional role of Go.
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Affiliation(s)
- Meisheng Jiang
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA.
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28
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Liu HT, Akita T, Shimizu T, Sabirov RZ, Okada Y. Bradykinin-induced astrocyte-neuron signalling: glutamate release is mediated by ROS-activated volume-sensitive outwardly rectifying anion channels. J Physiol 2009; 587:2197-209. [PMID: 19188250 DOI: 10.1113/jphysiol.2008.165084] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Glial cells release gliotransmitters which signal to adjacent neurons and glial cells. Previous studies showed that in response to stimulation with bradykinin, glutamate is released from rat astrocytes and causes NMDA receptor-mediated elevation of intracellular Ca(2+) in adjacent neurons. Here, we investigate how bradykinin-induced glutamate release from mouse astrocytes signals to neighbouring neurons in co-cultures. Astrocyte-to-neuron signalling and bradykinin-induced glutamate release from mouse astrocytes were both inhibited by the anion channel blocker 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) and phloretin. Glutamate release was also sensitive to 4-(2-Butyl-6,7-dichlor-2-cyclopentylindan-1-on-5-yl) oxybutyric acid (DCPIB), a specific blocker of the volume-sensitive outwardly rectifying anion channel (VSOR). Astrocytes, but not neurons, responded to bradykinin with activation of whole-cell Cl- currents. Although astrocytes stimulated with bradykinin did not undergo cell swelling, the bradykinin-activated current exhibited properties typical of VSOR: outward rectification, inhibition by osmotic shrinkage, sensitivity to DIDS, phloretin and DCPIB, dependence on intracellular ATP, and permeability to glutamate. Bradykinin increased intracellular reactive oxygen species (ROS) in mouse astrocytes. Pretreatment of mouse astrocytes with either a ROS scavenger or an NAD(P)H oxidase inhibitor blocked bradykinin-induced activation of VSOR, glutamate release and astrocyte-to-neuron signalling. By contrast, pretreatment with BAPTA-AM or tetanus neurotoxin A failed to suppress bradykinin-induced glutamate release. Thus, VSOR activated by ROS in mouse astrocytes in response to stimulation with bradykinin, serves as the pathway for glutamate release to mediate astrocyte-to-neuron signalling. Since bradykinin is an initial mediator of inflammation, VSOR might play a role in glia-neuron communication in the brain during inflammation.
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Affiliation(s)
- Hong-Tao Liu
- Department of Cell Physiology, National Institute for Physiological Sciences, 38 Nishigonaka, Myodaiji-cho, Okazaki, Aichi 444-8585, Japan
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Darna M, Schmutz I, Richter K, Yelamanchili SV, Pendyala G, Höltje M, Albrecht U, Ahnert-Hilger G. Time of Day-dependent Sorting of the Vesicular Glutamate Transporter to the Plasma Membrane. J Biol Chem 2009; 284:4300-7. [DOI: 10.1074/jbc.m805480200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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30
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Höltje M, Djalali S, Hofmann F, Münster-Wandowski A, Hendrix S, Boato F, Dreger SC, Grosse G, Henneberger C, Grantyn R, Just I, Ahnert-Hilger G. A 29-amino acid fragment of Clostridium botulinum C3 protein enhances neuronal outgrowth, connectivity, and reinnervation. FASEB J 2008; 23:1115-26. [PMID: 19047066 DOI: 10.1096/fj.08-116855] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Small GTPases of the Rho family play versatile roles in the formation and development of axons and dendrites, effects often studied by the Rho-inactivating C3 transferase (C3bot) from Clostridium botulinum. Recently, we reported that transferase-deficient C3bot also exerted axonotrophic activity. Using overlapping peptides from the C3bot sequence, we identified a small peptide of 29 amino acids (covering residues 154-182) from the C-terminal region of C3bot that promotes both axonal and dendritic growth, as well as branching of hippocampal neurons, at submicromolar concentrations. Several C3bot constructs, including the short peptide, enhanced the number of axonal segments from mid- to higher-order segments. C3bot(154-182) also increased the number of synaptophysin-expressing terminals, up-regulated various synaptic proteins, and functionally increased the glutamate uptake. Staining against the vesicular glutamate and GABA transporters further revealed that the effect was attributable to a higher number of glutamatergic and GABAergic inputs on proximal dendrites of enhanced green fluorescent protein (EGFP)-transfected neurons. Using organotypical slice cultures, we also detected trophic effects of C3bot(154-182) on length and density of outgrowing fibers from the entorhinal cortex that were comparable to the effects elicited by full-length C3bot. In addition, an enhanced reinnervation was observed in a hippocampal-entorhinal lesion model. In summary, the neurotrophic effect of C3bot is executed by a C-terminal peptide fragment covering aa 154-182 of C3; it triggers dendritic and axonal growth and branching as well as increased synaptic connectivity. In contrast to full-length C3, this C3 peptide selectively acts on neurons but not on glial cells.
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Affiliation(s)
- Markus Höltje
- Centrum für Anatomie, AG Funktionelle Zellbiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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