1
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Wilson EL, Yu Y, Leal NS, Woodward JA, Patikas N, Morris JL, Field SF, Plumbly W, Paupe V, Chowdhury SR, Antrobus R, Lindop GE, Adia YM, Loh SHY, Prudent J, Martins LM, Metzakopian E. Genome-wide CRISPR/Cas9 screen shows that loss of GET4 increases mitochondria-endoplasmic reticulum contact sites and is neuroprotective. Cell Death Dis 2024; 15:203. [PMID: 38467609 PMCID: PMC10928201 DOI: 10.1038/s41419-024-06568-y] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 02/13/2024] [Accepted: 02/19/2024] [Indexed: 03/13/2024]
Abstract
Organelles form membrane contact sites between each other, allowing for the transfer of molecules and signals. Mitochondria-endoplasmic reticulum (ER) contact sites (MERCS) are cellular subdomains characterized by close apposition of mitochondria and ER membranes. They have been implicated in many diseases, including neurodegenerative, metabolic, and cardiac diseases. Although MERCS have been extensively studied, much remains to be explored. To uncover novel regulators of MERCS, we conducted a genome-wide, flow cytometry-based screen using an engineered MERCS reporter cell line. We found 410 genes whose downregulation promotes MERCS and 230 genes whose downregulation decreases MERCS. From these, 29 genes were selected from each population for arrayed screening and 25 were validated from the high population and 13 from the low population. GET4 and BAG6 were highlighted as the top 2 genes that upon suppression increased MERCS from both the pooled and arrayed screens, and these were subjected to further investigation. Multiple microscopy analyses confirmed that loss of GET4 or BAG6 increased MERCS. GET4 and BAG6 were also observed to interact with the known MERCS proteins, inositol 1,4,5-trisphosphate receptors (IP3R) and glucose-regulated protein 75 (GRP75). In addition, we found that loss of GET4 increased mitochondrial calcium uptake upon ER-Ca2+ release and mitochondrial respiration. Finally, we show that loss of GET4 rescues motor ability, improves lifespan and prevents neurodegeneration in a Drosophila model of Alzheimer's disease (Aβ42Arc). Together, these results suggest that GET4 is involved in decreasing MERCS and that its loss is neuroprotective.
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Affiliation(s)
- Emma L Wilson
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Yizhou Yu
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Nuno S Leal
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - James A Woodward
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Nikolaos Patikas
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
| | - Jordan L Morris
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Sarah F Field
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
| | - William Plumbly
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
| | - Vincent Paupe
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Suvagata R Chowdhury
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Rd, Cambridge, CB2 0XY, UK
| | - Georgina E Lindop
- Cambridge Advanced Imaging Centre, University of Cambridge, Anatomy Building, Downing Site, Cambridge, CB2 3DY, UK
| | - Yusuf M Adia
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Samantha H Y Loh
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Julien Prudent
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK.
| | - L Miguel Martins
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK.
| | - Emmanouil Metzakopian
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK.
- bit bio, The Dorothy Hodgkin Building, Babraham Research Campus, Cambridge, CB22 3FH, UK.
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2
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Janer A, Morris JL, Krols M, Antonicka H, Aaltonen MJ, Lin ZY, Anand H, Gingras AC, Prudent J, Shoubridge EA. ESYT1 tethers the ER to mitochondria and is required for mitochondrial lipid and calcium homeostasis. Life Sci Alliance 2024; 7:e202302335. [PMID: 37931956 PMCID: PMC10627786 DOI: 10.26508/lsa.202302335] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/08/2023] Open
Abstract
Mitochondria interact with the ER at structurally and functionally specialized membrane contact sites known as mitochondria-ER contact sites (MERCs). Combining proximity labelling (BioID), co-immunoprecipitation, confocal microscopy and subcellular fractionation, we found that the ER resident SMP-domain protein ESYT1 was enriched at MERCs, where it forms a complex with the outer mitochondrial membrane protein SYNJ2BP. BioID analyses using ER-targeted, outer mitochondrial membrane-targeted, and MERC-targeted baits, confirmed the presence of this complex at MERCs and the specificity of the interaction. Deletion of ESYT1 or SYNJ2BP reduced the number and length of MERCs. Loss of the ESYT1-SYNJ2BP complex impaired ER to mitochondria calcium flux and provoked a significant alteration of the mitochondrial lipidome, most prominently a reduction of cardiolipins and phosphatidylethanolamines. Both phenotypes were rescued by reexpression of WT ESYT1 and an artificial mitochondria-ER tether. Together, these results reveal a novel function for ESYT1 in mitochondrial and cellular homeostasis through its role in the regulation of MERCs.
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Affiliation(s)
- Alexandre Janer
- https://ror.org/01pxwe438 Department of Human Genetics, McGill University, Montreal, Canada
- https://ror.org/01pxwe438 Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Jordan L Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Michiel Krols
- https://ror.org/01pxwe438 Montreal Neurological Institute, McGill University, Montreal, Canada
- https://ror.org/01pxwe438 Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
| | - Hana Antonicka
- https://ror.org/01pxwe438 Department of Human Genetics, McGill University, Montreal, Canada
- https://ror.org/01pxwe438 Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Mari J Aaltonen
- https://ror.org/01pxwe438 Department of Human Genetics, McGill University, Montreal, Canada
- https://ror.org/01pxwe438 Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Zhen-Yuan Lin
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Hanish Anand
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Eric A Shoubridge
- https://ror.org/01pxwe438 Department of Human Genetics, McGill University, Montreal, Canada
- https://ror.org/01pxwe438 Montreal Neurological Institute, McGill University, Montreal, Canada
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3
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Xue Y, Morris JL, Yang K, Fu Z, Zhu X, Johnson F, Meehan B, Witkowski L, Yasmeen A, Golenar T, Coatham M, Morin G, Monast A, Pilon V, Fiset PO, Jung S, Gonzalez AV, Camilleri-Broet S, Fu L, Postovit LM, Spicer J, Gotlieb WH, Guiot MC, Rak J, Park M, Lockwood W, Foulkes WD, Prudent J, Huang S. Author Correction: SMARCA4/2 loss inhibits chemotherapy-induced apoptosis by restricting IP3R3-mediated Ca 2+ flux to mitochondria. Nat Commun 2023; 14:1552. [PMID: 36944611 PMCID: PMC10030806 DOI: 10.1038/s41467-023-37144-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023] Open
Affiliation(s)
- Yibo Xue
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Division of Medical Genetics, McGill University Health Centre, and Cancer Research Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
| | - Jordan L Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Kangning Yang
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Zheng Fu
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Xianbing Zhu
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Fraser Johnson
- Department of Integrative Oncology, British Columbia Cancer Agency, Vancouver, BC, Canada
- Interdisciplinary Oncology Program, University of British Columbia, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Brian Meehan
- Department of Pediatrics, Research Institute of the McGill University Health Centre, Montreal Children's Hospital, McGill University, Montreal, QC, Canada
| | - Leora Witkowski
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Department of Specialized Medicine, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Amber Yasmeen
- Division of Gynecologic Oncology, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Tunde Golenar
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Mackenzie Coatham
- Department of Oncology, Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada
| | - Geneviève Morin
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Anie Monast
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Virginie Pilon
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | | | - Sungmi Jung
- Department of Pathology, McGill University Health Centre, Montreal, QC, Canada
| | - Anne V Gonzalez
- Department of Medicine, Division of Respiratory Medicine, McGill University Health Centre, Montreal Chest Institute, Montreal, QC, Canada
| | | | - Lili Fu
- Department of Pathology, McGill University Health Centre, Montreal, QC, Canada
| | - Lynne-Marie Postovit
- Department of Oncology, Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - Jonathan Spicer
- Department of Surgery, McGill University Health Center, Montreal, QC, Canada
| | - Walter H Gotlieb
- Division of Gynecologic Oncology, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Marie-Christine Guiot
- Department of Pathology, Montreal Neurological Hospital/Institute, McGill University Health Centre, Montreal, QC, Canada
| | - Janusz Rak
- Department of Pediatrics, Research Institute of the McGill University Health Centre, Montreal Children's Hospital, McGill University, Montreal, QC, Canada
| | - Morag Park
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - William Lockwood
- Department of Integrative Oncology, British Columbia Cancer Agency, Vancouver, BC, Canada
- Interdisciplinary Oncology Program, University of British Columbia, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - William D Foulkes
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Division of Medical Genetics, McGill University Health Centre, and Cancer Research Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
- Department of Specialized Medicine, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
| | - Sidong Huang
- Department of Biochemistry, McGill University, Montreal, QC, Canada.
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada.
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4
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Zecchini V, Paupe V, Herranz-Montoya I, Janssen J, Wortel IMN, Morris JL, Ferguson A, Chowdury SR, Segarra-Mondejar M, Costa ASH, Pereira GC, Tronci L, Young T, Nikitopoulou E, Yang M, Bihary D, Caicci F, Nagashima S, Speed A, Bokea K, Baig Z, Samarajiwa S, Tran M, Mitchell T, Johnson M, Prudent J, Frezza C. Fumarate induces vesicular release of mtDNA to drive innate immunity. Nature 2023; 615:499-506. [PMID: 36890229 PMCID: PMC10017517 DOI: 10.1038/s41586-023-05770-w] [Citation(s) in RCA: 59] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 01/30/2023] [Indexed: 03/10/2023]
Abstract
Mutations in fumarate hydratase (FH) cause hereditary leiomyomatosis and renal cell carcinoma1. Loss of FH in the kidney elicits several oncogenic signalling cascades through the accumulation of the oncometabolite fumarate2. However, although the long-term consequences of FH loss have been described, the acute response has not so far been investigated. Here we generated an inducible mouse model to study the chronology of FH loss in the kidney. We show that loss of FH leads to early alterations of mitochondrial morphology and the release of mitochondrial DNA (mtDNA) into the cytosol, where it triggers the activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING)-TANK-binding kinase 1 (TBK1) pathway and stimulates an inflammatory response that is also partially dependent on retinoic-acid-inducible gene I (RIG-I). Mechanistically, we show that this phenotype is mediated by fumarate and occurs selectively through mitochondrial-derived vesicles in a manner that depends on sorting nexin 9 (SNX9). These results reveal that increased levels of intracellular fumarate induce a remodelling of the mitochondrial network and the generation of mitochondrial-derived vesicles, which allows the release of mtDNAin the cytosol and subsequent activation of the innate immune response.
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Affiliation(s)
- Vincent Zecchini
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
| | - Vincent Paupe
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Irene Herranz-Montoya
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- Molecular Oncology Programme, Growth Factors, Nutrients and Cancer Group Centro Nacional de Investigaciones Oncológicas (CNIO), Madrid, Spain
| | - Joëlle Janssen
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Inge M N Wortel
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- Department of Data Science, Institute for Computing and Information Sciences, Radboud University, Nijmegen, The Netherlands
| | - Jordan L Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Ashley Ferguson
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
| | - Suvagata Roy Chowdury
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Marc Segarra-Mondejar
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- CECAD Research Centre, University of Cologne, Cologne, Germany
| | - Ana S H Costa
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- Matterworks, Somerville, MA, USA
| | - Gonçalo C Pereira
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Laura Tronci
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- Cogentech SRL Benefit Corporation, Milan, Italy
| | - Timothy Young
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
| | | | - Ming Yang
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- CECAD Research Centre, University of Cologne, Cologne, Germany
| | - Dóra Bihary
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
- VIB KU Leuven Center for Cancer Biology, Leuven, Belgium
| | | | - Shun Nagashima
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
- Laboratory of Regenerative Medicine, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Alyson Speed
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
| | - Kalliopi Bokea
- Department of Surgical Biotechnology, Division of Surgery and Interventional Science, UCL, London, UK
| | - Zara Baig
- Division of Infection and Immunity, Institute of Immunity and Transplantation, UCL, London, UK
| | - Shamith Samarajiwa
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK
| | - Maxine Tran
- Department of Surgical Biotechnology, Division of Surgery and Interventional Science, UCL, London, UK
| | - Thomas Mitchell
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK
- Department of Surgery, University of Cambridge, Cambridge, UK
| | - Mark Johnson
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
| | - Christian Frezza
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, UK.
- CECAD Research Centre, University of Cologne, Cologne, Germany.
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5
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Miljkovic JL, Burger N, Gawel JM, Mulvey JF, Norman AAI, Nishimura T, Tsujihata Y, Logan A, Sauchanka O, Caldwell ST, Morris JL, Prime TA, Warrington S, Prudent J, Bates GR, Aksentijević D, Prag HA, James AM, Krieg T, Hartley RC, Murphy MP. Rapid and selective generation of H 2S within mitochondria protects against cardiac ischemia-reperfusion injury. Redox Biol 2022; 55:102429. [PMID: 35961099 PMCID: PMC9382561 DOI: 10.1016/j.redox.2022.102429] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/22/2022] [Accepted: 08/01/2022] [Indexed: 02/02/2023] Open
Abstract
Mitochondria-targeted H2S donors are thought to protect against acute ischemia-reperfusion (IR) injury by releasing H2S that decreases oxidative damage. However, the rate of H2S release by current donors is too slow to be effective upon administration following reperfusion. To overcome this limitation here we develop a mitochondria-targeted agent, MitoPerSulf that very rapidly releases H2S within mitochondria. MitoPerSulf is quickly taken up by mitochondria, where it reacts with endogenous thiols to generate a persulfide intermediate that releases H2S. MitoPerSulf is acutely protective against cardiac IR injury in mice, due to the acute generation of H2S that inhibits respiration at cytochrome c oxidase thereby preventing mitochondrial superoxide production by lowering the membrane potential. Mitochondria-targeted agents that rapidly generate H2S are a new class of therapy for the acute treatment of IR injury.
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Affiliation(s)
- Jan Lj Miljkovic
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Nils Burger
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Justyna M Gawel
- School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK
| | - John F Mulvey
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | | | - Takanori Nishimura
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK; Innovative Biology Laboratories, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 251-8555, Japan
| | - Yoshiyuki Tsujihata
- Innovative Biology Laboratories, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 251-8555, Japan
| | - Angela Logan
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Olga Sauchanka
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | | | - Jordan L Morris
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Tracy A Prime
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | | | - Julien Prudent
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Georgina R Bates
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Dunja Aksentijević
- Centre for Biochemical Pharmacology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London, United Kingdom
| | - Hiran A Prag
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK; Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Andrew M James
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK
| | - Thomas Krieg
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | | | - Michael P Murphy
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, CB2 0XY, UK; Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK.
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6
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Lurette O, Guedouari H, Morris JL, Martín-Jiménez R, Robichaud JP, Hamel-Côté G, Khan M, Dauphinee N, Pichaud N, Prudent J, Hebert-Chatelain E. Mitochondrial matrix-localized Src kinase regulates mitochondrial morphology. Cell Mol Life Sci 2022; 79:327. [PMID: 35637383 PMCID: PMC9151517 DOI: 10.1007/s00018-022-04325-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 11/15/2021] [Revised: 04/19/2022] [Accepted: 04/22/2022] [Indexed: 02/02/2023]
Abstract
The architecture of mitochondria adapts to physiological contexts: while mitochondrial fragmentation is usually associated to quality control and cell death, mitochondrial elongation often enhances cell survival during stress. Understanding how these events are regulated is important to elucidate how mitochondrial dynamics control cell fate. Here, we show that the tyrosine kinase Src regulates mitochondrial morphology. Deletion of Src increased mitochondrial size and reduced cellular respiration independently of mitochondrial mass, mitochondrial membrane potential or ATP levels. Re-expression of Src targeted to the mitochondrial matrix, but not of Src targeted to the plasma membrane, rescued mitochondrial morphology in a kinase activity-dependent manner. These findings highlight a novel function for Src in the control of mitochondrial dynamics.
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Affiliation(s)
- Olivier Lurette
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Hala Guedouari
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Jordan L. Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY UK
| | - Rebeca Martín-Jiménez
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Julie-Pier Robichaud
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Geneviève Hamel-Côté
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Mehtab Khan
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Nicholas Dauphinee
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
| | - Nicolas Pichaud
- Department of Chemistry and Biochemistry, University of Moncton, Moncton, NB Canada
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY UK
| | - Etienne Hebert-Chatelain
- Canada Research Chair in Mitochondrial Signaling and Physiopathology, Moncton, NB Canada ,Department of Biology, University of Moncton, Moncton, NB Canada
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7
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Xue Y, Morris JL, Yang K, Fu Z, Zhu X, Johnson F, Meehan B, Witkowski L, Yasmeen A, Golenar T, Coatham M, Morin G, Monast A, Pilon V, Fiset PO, Jung S, Gonzalez AV, Camilleri-Broet S, Fu L, Postovit LM, Spicer J, Gotlieb WH, Guiot MC, Rak J, Park M, Lockwood W, Foulkes WD, Prudent J, Huang S. SMARCA4/2 loss inhibits chemotherapy-induced apoptosis by restricting IP3R3-mediated Ca 2+ flux to mitochondria. Nat Commun 2021; 12:5404. [PMID: 34518526 PMCID: PMC8438089 DOI: 10.1038/s41467-021-25260-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [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: 08/19/2020] [Accepted: 07/27/2021] [Indexed: 12/25/2022] Open
Abstract
Inactivating mutations in SMARCA4 and concurrent epigenetic silencing of SMARCA2 characterize subsets of ovarian and lung cancers. Concomitant loss of these key subunits of SWI/SNF chromatin remodeling complexes in both cancers is associated with chemotherapy resistance and poor prognosis. Here, we discover that SMARCA4/2 loss inhibits chemotherapy-induced apoptosis through disrupting intracellular organelle calcium ion (Ca2+) release in these cancers. By restricting chromatin accessibility to ITPR3, encoding Ca2+ channel IP3R3, SMARCA4/2 deficiency causes reduced IP3R3 expression leading to impaired Ca2+ transfer from the endoplasmic reticulum to mitochondria required for apoptosis induction. Reactivation of SMARCA2 by a histone deacetylase inhibitor rescues IP3R3 expression and enhances cisplatin response in SMARCA4/2-deficient cancer cells both in vitro and in vivo. Our findings elucidate the contribution of SMARCA4/2 to Ca2+-dependent apoptosis induction, which may be exploited to enhance chemotherapy response in SMARCA4/2-deficient cancers.
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Affiliation(s)
- Yibo Xue
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Division of Medical Genetics, McGill University Health Centre, and Cancer Research Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
| | - Jordan L Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Kangning Yang
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Zheng Fu
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Xianbing Zhu
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Fraser Johnson
- Department of Integrative Oncology, British Columbia Cancer Agency, Vancouver, BC, Canada
- Interdisciplinary Oncology Program, University of British Columbia, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Brian Meehan
- Department of Pediatrics, Research Institute of the McGill University Health Centre, Montreal Children's Hospital, McGill University, Montreal, QC, Canada
| | - Leora Witkowski
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Department of Specialized Medicine, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Amber Yasmeen
- Division of Gynecologic Oncology, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Tunde Golenar
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Mackenzie Coatham
- Department of Oncology, Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada
| | - Geneviève Morin
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Anie Monast
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - Virginie Pilon
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | | | - Sungmi Jung
- Department of Pathology, McGill University Health Centre, Montreal, QC, Canada
| | - Anne V Gonzalez
- Department of Medicine, Division of Respiratory Medicine, McGill University Health Centre, Montreal Chest Institute, Montreal, QC, Canada
| | | | - Lili Fu
- Department of Pathology, McGill University Health Centre, Montreal, QC, Canada
| | - Lynne-Marie Postovit
- Department of Oncology, Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - Jonathan Spicer
- Department of Surgery, McGill University Health Center, Montreal, QC, Canada
| | - Walter H Gotlieb
- Division of Gynecologic Oncology, Segal Cancer Center, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Marie-Christine Guiot
- Department of Pathology, Montreal Neurological Hospital/Institute, McGill University Health Centre, Montreal, QC, Canada
| | - Janusz Rak
- Department of Pediatrics, Research Institute of the McGill University Health Centre, Montreal Children's Hospital, McGill University, Montreal, QC, Canada
| | - Morag Park
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | - William Lockwood
- Department of Integrative Oncology, British Columbia Cancer Agency, Vancouver, BC, Canada
- Interdisciplinary Oncology Program, University of British Columbia, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - William D Foulkes
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Division of Medical Genetics, McGill University Health Centre, and Cancer Research Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
- Department of Specialized Medicine, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
| | - Sidong Huang
- Department of Biochemistry, McGill University, Montreal, QC, Canada.
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada.
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8
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Tábara LC, Morris JL, Prudent J. The Complex Dance of Organelles during Mitochondrial Division. Trends Cell Biol 2021; 31:241-253. [PMID: 33446409 DOI: 10.1016/j.tcb.2020.12.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [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: 08/31/2020] [Revised: 11/28/2020] [Accepted: 12/07/2020] [Indexed: 12/17/2022]
Abstract
Mitochondria are dynamic organelles that undergo cycles of fission and fusion events depending on cellular requirements. During mitochondrial division, the GTPase dynamin-related protein-1 is recruited to endoplasmic reticulum (ER)-induced mitochondrial constriction sites where it drives fission. However, the events required to complete scission of mitochondrial membranes are not well understood. Here, we emphasize the recently described roles for Golgi-derived phosphatidylinositol 4-phosphate (PI4P)-containing vesicles in the last steps of mitochondrial division. We then propose how trans-Golgi network vesicles at mitochondria-ER contact sites and PI4P generation could mechanistically execute mitochondrial division, by recruiting PI4P effectors and/or the actin nucleation machinery. Finally, we speculate on mechanisms to explain why such a complex dance of different organelles is required to facilitate the remodelling of mitochondrial membranes.
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Affiliation(s)
- Luis-Carlos Tábara
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Jordan L Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
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9
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Morris JL, Baniak L, Belcher SM, Imes C, Luyster F, Scott PW, Sereika S, Chasens ER. 1056 Perceived Financial Difficulty Predicts Sleep Quality In Participants With Type 2 Diabetes And Obstructive Sleep Apnea. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.1052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
People with multiple chronic conditions such as type 2 diabetes (T2D) and obstructive sleep apnea (OSA) are at increased risk for poor sleep quality. It is unclear if social determinants of health (SDoH) such as race, perceived financial difficulty, education, gender, and marital status are associated with sleep quality in this population. The purpose of this cross-sectional secondary analysis of data from the Diabetes Sleep Treatment Trial was to explore SDoH and disease severity as predictors of sleep quality in persons with both OSA and T2D.
Methods
Disease severity was measured by Apnea-Hypopnea Index [(AHI) ≥ 5] and A1C for glycemic control. SDoH included perceived financial difficulty (none/moderate-severe), race (White/African American), sex (f/m), marital status (no/yes), education (≤ or > 2 years post high school), and age. Sleep quality was measured by Pittsburgh Sleep Quality Index (PSQI). Correlations and linear regression modeling investigated associations between SDoH and disease severity on sleep quality. Post-hoc correlations were explored for significant relations among SDoH.
Results
The sample (N = 229) was middle-aged (57.6 ± 10.0; 66 % White and 34% African American; and 54 % men vs. 46% women. Participants carried a high burden of disease (mean AHI = 20.7±18.1, mean A1C = 7.9 %±1.7%). Disease severity was not significantly associated with sleep quality (all p >.05). The perception of worse financial difficulty was the only SDoH that predicted worse sleep quality (b=-1.54, p=.015). Characteristics significantly associated with worse financial difficulty were being African American, female, ≤ 2 years post high school, and younger (all p<.01).
Conclusion
Financial difficulty may be a more important predictor of subjective measures of sleep quality than disease severity in patients with OSA and T2D. Researchers and clinicians should be aware of these characteristics as potential markers of vulnerability to poor sleep quality in this population.
Support
The National Institute of Diabetes and Digestive and Kidney Diseases (R01DK096028) and through the Clinical +Translational Research Institute grants UL1TR001857 and UL1TR000005.
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Affiliation(s)
- J L Morris
- University of Pittsburgh, Pittsburgh, PA
| | - L Baniak
- VA Pittsburgh Healthcare System, Pittsburgh, PA
| | | | - C Imes
- University of Pittsburgh, Pittsburgh, PA
| | - F Luyster
- University of Pittsburgh, Pittsburgh, PA
| | - P W Scott
- University of Pittsburgh, Pittsburgh, PA
| | - S Sereika
- University of Pittsburgh, Pittsburgh, PA
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10
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Dobson GP, Letson HL, Grant A, McEwen P, Hazratwala K, Wilkinson M, Morris JL. Defining the osteoarthritis patient: back to the future. Osteoarthritis Cartilage 2018; 26:1003-1007. [PMID: 29775734 DOI: 10.1016/j.joca.2018.04.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/30/2018] [Accepted: 04/09/2018] [Indexed: 02/08/2023]
Abstract
The history of osteoarthritis (OA) is important because it can help broaden our perspective on past and present controversies. The naming of OA, beginning with Heberden's nodes, is itself a fascinating story. According to Albert Hoffa, R. Llewellyn Jones and Archibald Edward Garrod, the name OA was introduced in the mid-nineteenth century by surgeon Richard von Volkmann who distinguished it from rheumatoid arthritis and gout. Others preferred the terms 'chronical rheumatism', 'senile arthritis', 'hypertrophic arthritis' or 'arthritis deformans'. A similar narrative applies to the concept of OA affecting the whole joint vs the 'wear-and-tear' hypothesis, inflammation and the role of the central nervous system (CNS). In the late nineteenth and early twentieth centuries, the Garrods (father and son) and Hermann Senator argued that OA was a whole joint disease, and that inflammation played a major role in its progression. Garrod Jnr and John Spender also linked OA to a neurogenic lesion 'outside the joint'. The remaining twentieth century was no less dynamic, with major advances in basic science, diagnostics, treatments, surgical interventions and technologies. Today, OA is characterized as a multi-disease with inflammation, immune and CNS dysfunction playing central roles in whole joint damage, injury progression, pain and disability. In the current 'omics' era (genomics, proteomics and metabolomics), we owe a great debt to past physicians and surgeons who dared to think 'outside-the-box' to explain and treat OA. Over 130 years later, despite these developments, we still don't fully understand the underlying complexities of OA, and we still don't have a cure.
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Affiliation(s)
- G P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| | - H L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| | - A Grant
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia; Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| | - P McEwen
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia.
| | - K Hazratwala
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia.
| | - M Wilkinson
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia.
| | - J L Morris
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia; Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
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11
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Graves LY, Imes CC, Morris JL, Williams E, Yang K, Chasens ER. 0967 Sleep Duration in Older Adult Men Predictive of Depression. Sleep 2018. [DOI: 10.1093/sleep/zsy061.966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- L Y Graves
- University of Pittsburgh, Pittsburgh, PA
| | - C C Imes
- University of Pittsburgh, Pittsburgh, PA
| | - J L Morris
- University of Pittsburgh, Pittsburgh, PA
| | - E Williams
- University of Pittsburgh, Pittsburgh, PA
| | - K Yang
- Rutgers, The State University of New Jersey, Newark, NJ
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12
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Chasens ER, Atwood CW, Baniak LM, Burke LE, Korytkowski M, Morris JL, Sereika SM, Strollo PJ. 1014 INSOMNIA AND GLUCOSE CONTROL IN ADULTS WITH TYPE 2 DIABETES. Sleep 2017. [DOI: 10.1093/sleepj/zsx050.1013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Morris JL, Atwood C, Burke L, Baniak L, Korytkowski M, Sereika S, Strollo PJ, Chasens E. 1063 THE EFFECT OF SLEEP QUALITY ON INTIMATE RELATIONSHIPS AND SEXUAL ACTIVITY IN MEN AND WOMEN WITH TYPE 2 DIABETES. Sleep 2017. [DOI: 10.1093/sleepj/zsx050.1062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14
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Rathore S, Stables RH, Pauriah M, Hakeem A, Mills JD, Palmer ND, Perry R, Morris JL. 032 Impact of length and hydrophilic coating of the introducer sheath on radial artery spasm during transradial coronary intervention: a randomised study. Heart 2015. [DOI: 10.1136/hrt.2010.195958.6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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15
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Rathore S, Stables RH, Pauriah M, Hakeem M, Mills JD, Palmer ND, Perry RA, Morris JL. 034 A randomised comparison of TR band and Radistop haemostatic compression devices after transradial coronary intervention. Heart 2010. [DOI: 10.1136/hrt.2010.195958.8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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16
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Ramos-Montañez S, Tsui HCT, Wayne KJ, Morris JL, Peters LE, Zhang F, Kazmierczak KM, Sham LT, Winkler ME. Polymorphism and regulation of the spxB (pyruvate oxidase) virulence factor gene by a CBS-HotDog domain protein (SpxR) in serotype 2 Streptococcus pneumoniae. Mol Microbiol 2007; 67:729-46. [PMID: 18179423 DOI: 10.1111/j.1365-2958.2007.06082.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
spxB-encoded pyruvate oxidase is a major virulence factor of Streptococcus pneumoniae. During aerobic growth, SpxB synthesizes H2O2 and acetyl phosphate, which play roles in metabolism, signalling, and oxidative stress. We report here the first cis- and trans-acting regulatory elements for spxB transcription. These elements were identified in a genetic screen for spontaneous mutations that caused colonies of strain D39 to change from a semitransparent to an opaque appearance. Six of the seven opaque colonies recovered (frequency approximately 3 x 10(-5)) were impaired for SpxB function or expression. Two mutations changed amino acids in SpxB likely required for cofactor or subunit binding. One mutation defined a cis-acting adjacent direct repeat required for optimal spxB transcription. The other three spontaneous mutations created the same frameshift near the start of the trans-acting spxR regulatory gene. The SpxR protein contains helix-turn-helix, CBS and HotDog domains implicated in binding DNA, adenosyl compounds, and CoA-containing compounds respectively, and suggest that SpxR positively regulates spxB transcription in response to energy and metabolic state. Microarray analyses unexpectedly demonstrated that SpxR also positively regulates the strH exoglycosidase gene, which, like spxB, has been implicated in colonization. Finally, SpxR is required for full virulence in a murine model of infection.
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17
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Velavan P, Morris JL. Broad complex tachycardia caused by adrenal tumour and atrial septal defect. J Postgrad Med 2005; 51:337-8. [PMID: 16388187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
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18
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Jobling P, Gibbins IL, Lewis RJ, Morris JL. Differential expression of calcium channels in sympathetic and parasympathetic preganglionic inputs to neurons in paracervical ganglia of guinea-pigs. Neuroscience 2004; 127:455-66. [PMID: 15262335 DOI: 10.1016/j.neuroscience.2004.05.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Revised: 04/27/2004] [Accepted: 05/05/2004] [Indexed: 11/24/2022]
Abstract
Neurons in pelvic ganglia receive nicotinic excitatory post-synaptic potentials (EPSPs) from sacral preganglionic neurons via the pelvic nerve, lumbar preganglionic neurons via the hypogastric nerve or both. We tested the effect of a range of calcium channel antagonists on EPSPs evoked in paracervical ganglia of female guinea-pigs after pelvic or hypogastric nerve stimulation. omega-Conotoxin GVIA (CTX GVIA, 100 nM) or the novel N-type calcium channel antagonist, CTX CVID (100 nM) reduced the amplitude of EPSPs evoked after pelvic nerve stimulation by 50-75% but had no effect on EPSPs evoked by hypogastric nerve stimulation. Combined addition of CTX GVIA and CTX CVID was no more effective than either antagonist alone. EPSPs evoked by stimulating either nerve trunk were not inhibited by the P/Q calcium channel antagonist, omega-agatoxin IVA (100 nM), nor the L-type calcium channel antagonist, nifedipine (30 microM). SNX 482 (300 nM), an antagonist at some R-type calcium channels, inhibited EPSPs after hypogastric nerve stimulation by 20% but had little effect on EPSPs after pelvic nerve stimulation. Amiloride (100 microM) inhibited EPSPs after stimulation of either trunk by 40%, while nickel (100 microM) was ineffective. CTX GVIA or CTX CVID (100 nM) also slowed the rate of action potential repolarization and reduced afterhyperpolarization amplitude in paracervical neurons. Thus, release of transmitter from the terminals of sacral preganglionic neurons is largely dependent on calcium influx through N-type calcium channels, although an unknown calcium channel which is resistant to selective antagonists also contributes to release. Release of transmitter from lumbar preganglionic neurons does not require calcium entry through either conventional N-type calcium channels or the variant CTX CVID-sensitive N-type calcium channel and seems to be mediated largely by a novel calcium channel.
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Affiliation(s)
- P Jobling
- Department of Anatomy and Histology, Centre for Neuroscience, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia.
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19
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Keadle TL, Morris JL, Pepose JS, Stuart PM. CD4(+) and CD8(+) cells are key participants in the development of recurrent herpetic stromal keratitis in mice. Microb Pathog 2002; 32:255-62. [PMID: 12137752 DOI: 10.1006/mpat.2002.0506] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ocular herpes simplex virus (HSV) infection results in an immune-mediated inflammation of the corneal stroma known as herpetic stromal keratitis (HSK). Recurrent HSK is a common cause of virus-induced corneal blindness in humans. The role of CD4(+) and CD8(+) T cell subsets in the disease pathogenesis is ill defined and varies with the virus strain and host genetic background. To examine the contribution of T cell subsets to corneal disease, we studied the development of recurrent HSK in CD4 or CD8 gene knockout (KO) mice ocularly infected with HSV-1 McKrae strain. Following UV-B induced viral reactivation, corneal opacity in latently infected BALB/c (HSV sensitive) CD4 and CD8 KO mice was reduced compared to infected BALB/c mice with normal genotype. In contrast, opacity in C57BL/6 (HSV resistant) CD4 and CD8 KO latent mice did not differ from genetically normal latent mice. Virus-induced corneal opacity was not demonstrable in C57BL/6 CD4/CD8 double KO mice. Increased viral shedding, measured by reactivation rate, days shedding or viral titers, occurred in CD4 KO mice of both strains. Our findings indicate that both CD4(+) and CD8(+) cells play a role in the immunopathogenesis of recurrent HSK, and their role is dependent upon the host genetic profile.
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Affiliation(s)
- T L Keadle
- Washington University School Medicine, Department of Ophthalmology and Visual Sciences, Box 8096, 660 S. Euclid, St. Louis, MO, 63110, US.
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20
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Hutton JT, Morris JL. Vision in Parkinson's disease. Adv Neurol 2002; 86:279-88. [PMID: 11553987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Affiliation(s)
- J T Hutton
- Neurology Research and Education Center, Covenant Health System, Lubbock, Texas 79410, USA
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21
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Shimizu T, Morris JL, Gibbins IL. Expression of immunoreactivity to neurokinin-1 receptor by subsets of cranial parasympathetic neurons: correlation with neuropeptides, nitric oxide synthase, and pathways. Exp Neurol 2001; 172:293-306. [PMID: 11716554 DOI: 10.1006/exnr.2001.7799] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined the patterns of coexistence of immunoreactivity to the neurokinin-1 (NK(1)) tachykinin receptor, nitric oxide synthase, and neuropeptides in the sphenopalatine and otic ganglia of guinea pigs using a combination of multiple-labeling immunohistochemistry and pathway tracing in vitro. Most neurons had immunoreactivity to vasoactive intestinal peptide (85-96%) and neuropeptide Y (60%). Subpopulations of vasoactive intestinal peptide-immunoreactive neurons also had immunoreactivity to nitric oxide synthase (37-48%) or enkephalin (25-35%), but these formed mutually exclusive populations. Almost all neurons expressing NK(1) receptor immunoreactivity contained immunoreactivity to enkephalin, vasoactive intestinal peptide, and neuropeptide Y, but not nitric oxide synthase. Using a combination of retrograde axonal tracing and axonal crushing, we found that most neurons with immunoreactivity to nitric oxide synthase projected along the nasopalatine and ethmoidal nerves to the nasal mucosa. In contrast, most neurons with immunoreactivity to enkephalin followed the zygomatic nerve to the facial skin and lacrimal gland. Based on their peptide content, we conclude that the neurons with immunoreactivity to enkephalin and NK(1) receptor projected selectively to the skin. In both the sphenopalatine and the otic ganglia, about half of the neurons with NK(1) receptor immunoreactivity were surrounded by varicose nerve fibers with substance P immunoreactivity. Many of these fibers are likely to have originated in the trigeminal ganglion. Taken together, these observations establish a strong anatomical basis for a range of interactions between trigeminal and cranial parasympathetic pathways that may underlie pathophysiological conditions such as trigeminal neuralgia.
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Affiliation(s)
- T Shimizu
- Department of Anatomy & Histology, Flinders University of South Australia, Adelaide, South Australia, 5001, Australia
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22
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Abstract
The role of the soluble NSF attachment protein receptor (SNARE) protein complex in release of multiple cotransmitters from autonomic vasodilator neurons was examined in isolated segments of guinea pig uterine arteries treated with botulinum neurotoxin A (BoNTA; 50 nM). Western blotting of protein extracts from uterine arteries demonstrated partial cleavage of synaptosomal-associated protein of 25 kDa (SNAP-25) to a NH2-terminal fragment of approximately 24 kDa by BoNTA. BoNTA reduced the amplitude (by 70-80%) of isometric contractions of arteries in response to repeated electrical stimulation of sympathetic axons at 1 or 10 Hz. The amplitude of neurogenic relaxations mediated by neuronal nitric oxide (NO) was not affected by BoNTA, whereas the duration of peptide-mediated neurogenic relaxations to stimulation at 10 Hz was reduced (67% reduction in integrated responses). In contrast, presynaptic cholinergic inhibition of neurogenic relaxations was abolished by BoNTA. These results demonstrate that the SNARE complex has differential involvement in release of cotransmitters from the same autonomic neurons: NO release is not dependent on synaptic vesicle exocytosis, acetylcholine release from small vesicles is highly dependent on the SNARE complex, and neuropeptide release from large vesicles involves SNARE proteins that may interact differently with regulatory factors such as calcium.
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Affiliation(s)
- J L Morris
- Department of Anatomy and Histology, Centre for Neuroscience, Flinders University, Adelaide SA 5001, Australia.
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23
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Morris JL, Anderson RL, Gibbins IL. Neuropeptide Y immunoreactivity in cutaneous sympathetic and sensory neurons during development of the guinea pig. J Comp Neurol 2001; 437:321-34. [PMID: 11494259 DOI: 10.1002/cne.1286] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Different levels of the cutaneous vasculature are innervated selectively by subpopulations of sympathetic neurons distinguished by the presence or absence of immunoreactivity (-IR) for neuropeptide Y (NPY). This study used multiple-labelling immunohistochemistry to examine the appearance of NPY-IR in neurons innervating cutaneous vessels in the ear pinna of embryonic, fetal, and neonatal guinea pigs. NPY-immunoreactive axons were detected in the ear bud at embryonic day 25. However, these axons lacked IR for tyrosine hydroxylase (TH) and often ran in bundles with substance P (SP)-immunoreactive axons close to the epidermis. Many neuronal somata in the cervical dorsal root ganglia (DRG) at late embryonic stages contained NPY-IR with or without SP-IR, but no NPY-IR was detected in DRG or subepidermal axons by late fetal stages. IR for calcitonin gene-related peptide increased in DRG neurons from midfetal to late fetal stages, after the decrease in NPY-IR. Populations of TH-IR neurons with or without NPY-IR were present in the superior cervical ganglion (SCG) from midembryonic stages. TH-immunoreactive axons were not detected in the ear pinna until midfetal stages, when axons with TH-IR and NPY-IR innervated proximal arteries and TH-immunoreactive axons without NPY-IR innervated distal vessels. Vasoactive intestinal peptide-IR was detected transiently in most fetal SCG neurons with TH-IR and NPY-IR but was not detected in cutaneous axons. These results demonstrate that selective expression of NPY by subpopulations of sympathetic neurons occurs prior to innervation of their targets. This suggests that target contact is not required to establish appropriate patterns of expression of peptide neurotransmitters by cutaneous sympathetic neurons.
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MESH Headings
- Aging/physiology
- Animals
- Animals, Newborn/embryology
- Animals, Newborn/growth & development
- Animals, Newborn/metabolism
- Blood Vessels/embryology
- Blood Vessels/innervation
- Blood Vessels/metabolism
- Cervical Vertebrae
- Ear/blood supply
- Ear/embryology
- Ear/innervation
- Ganglia, Spinal/cytology
- Ganglia, Spinal/embryology
- Ganglia, Spinal/metabolism
- Guinea Pigs/anatomy & histology
- Guinea Pigs/embryology
- Guinea Pigs/growth & development
- Immunohistochemistry
- Neurons, Afferent/cytology
- Neurons, Afferent/metabolism
- Neuropeptide Y/metabolism
- Skin/blood supply
- Skin/embryology
- Skin/innervation
- Superior Cervical Ganglion/cytology
- Superior Cervical Ganglion/embryology
- Superior Cervical Ganglion/metabolism
- Sympathetic Fibers, Postganglionic/cytology
- Sympathetic Fibers, Postganglionic/embryology
- Sympathetic Fibers, Postganglionic/metabolism
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Affiliation(s)
- J L Morris
- Department of Anatomy and Histology, Flinders University, Adelaide, South Australia 5001, Australia.
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Hutton JT, Metman LV, Chase TN, Juncos JL, Koller WC, Pahwa R, LeWitt PA, Samii A, Tsui JK, Calne DB, Waters CH, Calabrese VP, Bennett JP, Barrett R, Morris JL. Transdermal dopaminergic D(2) receptor agonist therapy in Parkinson's disease with N-0923 TDS: a double-blind, placebo-controlled study. Mov Disord 2001; 16:459-63. [PMID: 11391739 DOI: 10.1002/mds.1085] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
N-0923 is a non-ergot, dopaminergic D(2) agonist designed to be transdermally available. It has anti-parkinsonian effects when infused intravenously. An adhesive matrix patch was developed to deliver N-0923 transdermally (N-0923 TDS). In this phase II trial, we evaluated the effectiveness of various doses of N-0923 TDS at replacing levodopa. Eighty-five Parkinson's disease (PD) patients were randomized to placebo or one of four doses of N-0923 TDS for 21 days. Change in daily levodopa dose was the primary efficacy measure. Significantly greater reductions in levodopa dose were achieved as compared to placebo for the two highest doses of N-0923 TDS. Patients treated with 33.5 mg and 67 mg N-0923 TDS decreased levodopa use by 26% and 28%, vs. 7% for placebo. N-0923 TDS was safe and well tolerated.
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Affiliation(s)
- J T Hutton
- Neurology Research & Education Center, Covenant Medical Center-Lakeside, 4102 24th St., Lubbock, TX 79410, USA.
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Abstract
The coeliac ganglion of guinea pigs displays a unique topographical arrangement of neurochemically and functionally distinct populations of sympathetic neurons. The authors used multiple-labeling immunohistochemistry to investigate the neurochemical differentiation of these neurons during embryonic and fetal development. Sympathoadrenal precursors, located on either side of the abdominal aorta, were intensely immunoreactive for tyrosine hydroxylase (TH-IR), neurofilament, and the human natural killer 1 antibody at midembryonic stages (Carnegie stages 16-19). During late embryonic stages (stages 20-23), a single bilobed ganglion had formed. At this time, neuropeptide Y immunoreactivity (NPY-IR) was widely expressed in sympathetic neurons (with moderate TH-IR) and chromaffin cells (with intense TH-IR). The onset of somatostatin (Som-IR) expression followed that of NPY-IR and was restricted to sympathetic neurons. However, at late embryonic stages, most TH-IR neurons with Som-IR also expressed NPY-IR (a combination of peptides not found in the mature coeliac ganglion). Between late embryonic stages and the end of the early fetal period, there was a significant increase in the proportion of neurons in lateral regions that had both NPY-IR and TH-IR. At the same time, there was an increase in the proportion of neurons in medial regions that had both Som-IR and TH-IR. Neurons expressing both Som-IR and TH-IR were rarely observed in lateral regions of the coeliac ganglion. Thus, a clear topography within the coeliac ganglion is established during late embryonic and early fetal stages of development and reflects that found in the mature animal by the end of the early fetal period.
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Affiliation(s)
- R L Anderson
- Department of Anatomy and Histology, The Flinders University of South Australia, Adelaide, South Australia 5001, Australia.
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Morris JL, Lindberg CE, Gibbins IL. Different levels of immunoreactivity for synaptosomal-associated protein of 25 kDa in vasoconstrictor and vasodilator axons of guinea-pigs. Neurosci Lett 2000; 294:167-70. [PMID: 11072141 DOI: 10.1016/s0304-3940(00)01568-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Immunoreactivity (IR) for synaptosomal-associated protein of 25 kDa (SNAP-25) was examined in axons of autonomic vasoconstrictor and vasodilator neurons innervating the lingual and uterine arteries of guinea-pigs. Polyacrylamide gel electrophoresis and immunoblotting of protein extracts demonstrated a SNAP-25-IR band at 25 kDa in both arteries. Quantitative confocal microscopy demonstrated significantly higher levels of SNAP-25-IR in varicosities with IR for vasoactive intestinal peptide (VIP) than in adjacent axons with IR for tyrosine hydroxylase (TH). Levels of SNAP-25-IR in TH-IR axons, relative to adjacent VIP-IR axons, were significantly higher in the lingual artery than the uterine artery. These differences in IR for SNAP-25, a protein considered essential for calcium-dependent exocytosis of neurotransmitters, raise the possibility that mechanisms of transmitter release may vary between different classes of autonomic neurons.
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Affiliation(s)
- J L Morris
- Department of Anatomy and Histology, Centre for Neuroscience, School of Medicine, Flinders University, G.P.O. Box 2100, S.A. 5001, Adelaide, Australia.
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Abstract
BACKGROUND The aim of this work was to study changes in end-diastolic volume 6 months after Q-wave and non-Q-wave anterior ST-elevation myocardial infarction by echocardiography. Ventricular dilation after anterior Q-wave myocardial infarction is well-recognized. However, there is a dearth of information about the natural history of ventricular volumes after non-Q-wave myocardial infarction. METHODS One hundred ninety patients receiving thrombolytic therapy after anterior ST-elevation myocardial infarction were studied. All patients had 2D echocardiograms and 12-lead electrocardiograms recorded within 24 hours of symptoms and at 3, 42, and 180 days later. In addition, a further electrocardiogram was recorded on day 7 to assess patients for the presence of Q waves. Peak creatine kinase over the first 3 days of admission was recorded. End-diastolic volume index was the study end point. RESULTS Peak creatine kinase was strongly associated with ventricular dilation in both groups (P <.001). Mean end-diastolic volume in the Q-wave group increased significantly from day 1 to 6 months (P <.05) but did not alter after non-Q-wave infarction. However, when patients were selected on predefined criteria for significant change in ventricular dilation (>10 mL/m(2)), then 35% of those with and 15% of those without Q waves fell into this category. Within this group, the increase in end-diastolic volume followed a similar pattern, with the maximum percentage increase occurring between day 1 and 6 weeks. CONCLUSIONS In the postthrombolytic group of anterior ST-elevation myocardial infarction, a minority of patients without Q-wave development also undergo significant ventricular dilation.
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Affiliation(s)
- A G Zaman
- University Hospital of Wales, Cardiff, United Kingdom.
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Abstract
In this article, we review the immunohistochemical evidence for the pathway-specific expression of co-existing neuropeptides in autonomic vasomotor neurons, and examine the functional significance of these expression patterns for the autonomic regulation of the vasculature. Most final motor neurons in autonomic vasomotor pathways contain neuropeptides in addition to non-peptide co-transmitters such as catecholamines, acetylcholine and nitric oxide. Neuropeptides also occur in preganglionic vasomotor neurons. The precise combinations of neuropeptides expressed by neurons in vasomotor pathways vary with species, vascular bed, and the level within the vascular bed. This applies to both vasoconstrictor and vasodilator pathways. There is a similar degree of variation in the expression of neuropeptide receptors in the vasculature. Consequently, the contributions of different peptides to autonomic vasomotor control are closely matched to the functional requirements of specific vascular beds. This arrangement allows for a high degree of precision in vascular control in normal conditions and has the potential for considerable plasticity under pathophysiological conditions.
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Affiliation(s)
- I L Gibbins
- Department of Anatomy and Histology, and Centre for Neuroscience, School of Medicine, Flinders University, GPO Box 2100, S.A. 5001, Adelaide, Australia.
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Abstract
In this article, we provide a short review of the structure and synaptic organisation of the final motor neurons in the sympathetic ganglia of mammals. Combinations of pathway tracing, multiple-labelling immunofluorescence and intracellular dye injection have shown that neurons in different functional pathways differ not only in their patterns of neuropeptide expression, but also in the size of their cell bodies and dendritic fields. Thus, vasoconstrictor neurons consistently are smaller than any other major functional class of neurons. Serial section ultrastructural analysis of dye filled neurons, together with electron microscopic and confocal microscopic analysis of immunolabelled synaptic inputs to sympathetic final motor neurons indicate that synapses are rare and randomly distributed over the surface of the neurons. The total number of synapses is simply proportional to the total surface area of the neurons. Many terminal boutons of peptide-containing preganglionic neurons do not make conventional synapses with target neurons. Furthermore, there is a spatial mismatch in the distribution of peptide-containing terminals and neurons expressing receptors for the corresponding peptides. Together, these results suggest that there are likely to be significant differences in the ways that the final sympathetic motor neurons in distinct functional pathways integrate their synaptic inputs. In at least some pathways, heterosynaptic actions of neuropeptides probably contribute to subtle modulation of ganglionic transmission.
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Affiliation(s)
- I L Gibbins
- Department of Anatomy and Histology, Centre for Neuroscience, Flinders University of South Australia, GPO Box 2100, SA 5001, Adelaide, Australia.
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Rosen DA, Morris JL, Rosen KR, Nelson ER, Steelman RJ, Gustafson RA, Wilhelm JA, Chang CT, Thackara JW, Frye RF. Nalmefene to prevent epidural narcotic side effects in pediatric patients: a pharmacokinetic and safety study. Pharmacotherapy 2000; 20:745-9. [PMID: 10907964 DOI: 10.1592/phco.20.9.745.35207] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
STUDY OBJECTIVE To determine the pharmacokinetics and preliminary efficacy of nalmefene in children in preventing epidural-induced narcotic side effects. DESIGN Double-blind, placebo-controlled study. SETTING University-affiliated children's hospital. PATIENTS Thirty-four children (aged 2-12 yrs) undergoing cardiothoracic surgery with epidural anesthesia. INTERVENTIONS Patients were randomized to receive intravenous bolus nalmefene 1 microg/kg or placebo. MEASUREMENTS AND MAIN RESULTS Six blood samples (one before nalmefene administration and five from 13 randomly designated time points) from each patient were assayed to determine plasma nalmefene concentrations. Patients were assessed for pain, nausea, vomiting, and urinary retention for 24 hours after administration. Concentration-time data were analyzed by a limited sampling strategy with adult pharmacokinetic parameters used as Bayesian priors. A two-compartment, first-order model was fitted to the data using ADAPT II. Pharmacokinetic parameter estimates in these patients were similar to values reported in adults. The initial disposition half-life (t(1/2alpha)) was 0.36+/-0.11 hour, the terminal elimination half-life (t(1/2beta)) 8.7+/-2.3 hours, clearance 0.729+/-0.172 L/kg/hr, and steady-state volume of distribution 7.21+/-2.49 L/kg. Ability to prevent epidural narcotic-induced side effects could not be documented at the 1-microg/kg dose. No statistically significant differences were noted between study and placebo groups with regard to pain, nausea, vomiting, or urinary retention. CONCLUSION Nalmefene has similar pharmacokinetics in children as in adults. It was administered safely to these patients and did not produce unmanageable pain.
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Hutton JT, Tolosa ES, Capildeo R, Morris JL. Levodopa-treated Parkinson disease has better long-term outcome than previously predicted. Arch Neurol 2000; 57:758-9. [PMID: 10815149 DOI: 10.1001/archneur.57.5.758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Abstract
Eutectic mixture of local anesthetics (EMLA; Astra Pharmaceuticals, Wayne, PA) has been shown to reduce the pain of blood draws in children. We investigated the use of EMLA versus IV morphine for providing analgesia during chest tube removal (CTR) in children. One hundred twenty pediatric cardiothoracic surgery patients were enrolled. Patients were randomly assigned to receive either morphine (0.1 mg/kg up to 10 mg IV 30 min before CTR) or EMLA cream (5 g per chest tube cutaneously 3 h before CTR). A single, trained observer rated the patient's pain before, during, and after CTR using a 10-cm visual analog scale. The sites were evaluated for adverse effect. Methylhemoglobin levels were monitored in infants. Before CTR, the pain scores of the children who received morphine were rated lower than those who received EMLA (P < 0.01). During CTR, there was no difference in the pain score between the morphine or EMLA group. The change from baseline pain score in the morphine group was significantly larger than in the EMLA group (P < 0.01). We conclude that EMLA is safe and useful for blunting the pain of CTR.
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Affiliation(s)
- D A Rosen
- Department of Anesthesia, West Virginia University Children's Hospital, West Virginia University, Morgantown, WV 26506-9134, USA
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Abstract
The hamster cheek pouch and its retractor muscle have provided valuable insights into microvascular physiology of an epithelial tissue and striated muscle, respectively. Nevertheless, the innervation of these vascular beds has not been resolved. This study has investigated the nature of autonomic and sensory innervation of these vascular beds and has tested whether it varies within or between tissues. Multiple-labelling immunohistochemistry identified autonomic and peptide-containing sensory nerve fibres. Presumptive sympathetic vasoconstrictor axons with immunoreactivity (IR) for tyrosine hydroxylase (TH) and neuropeptide Y (NPY) innervated feed arteries and arterioles (but not veins or venules) of the retractor and anterior (muscular) cheek pouch; these axons were absent from the posterior (epithelial) region of the cheek pouch, as confirmed by catecholamine fluorescence. Presumptive autonomic vasodilator axons with IR for vasoactive intestinal peptide (VIP) consistently innervated feed arteries and proximal arterioles of the cheek pouch, but generally not those of the retractor muscle nor distal arterioles of either tissue. Sparse presumptive sensory axons with IR for calcitonin gene-related peptide (CGRP) and substance P were found near arterial and venous vessels in all regions of the cheek pouch and retractor muscle; CGRP-IR was also located in motor end plates associated with striated muscle fibres. Such regional differences in vascular innervation by autonomic and sensory neurons may selectively effect local and regional control of blood flow between and within vascular beds.
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Affiliation(s)
- D J Grasby
- Department of Anatomy and Histology, and Centre for Neuroscience, School of Medicine, Flinders University of South Australia, Adelaide, S.A., Australia
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Morris JL, Zhu BS, Gibbins IL, Blessing WW. Subpopulations of sympathetic neurons project to specific vascular targets in the pinna of the rabbit ear. J Comp Neurol 1999; 412:147-60. [PMID: 10440716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
We have characterised sympathetic neurons projecting to a range of cutaneous and striated muscle vascular targets in the pinna of the rabbit ear by examining neurotransmitter-related enzymes and peptides in perivascular axons and in somata identified by retrograde axonal tracing. Fast Blue was injected into one of seven sites in each pinna (n = 21 pinnae). The soma cross-sectional area and immunoreactivity (IR) for tyrosine hydroxylase (TH) and neuropeptide Y (NPY) were determined for each of 2,041 retrogradely labelled neurons in the ipsilateral superior cervical ganglion (SCG) or stellate ganglion (StG). Larger neurons in the SCG with TH-IR but not NPY-IR projected predominantly to veins along the medial edge of the pinna. Larger neurons in the StG with TH-IR but not NPY-IR projected predominantly to arteries and veins in the tip and lateral edge of the pinna. Smaller neurons in the SCG with IR to both TH and NPY projected predominantly to arteries in the striated muscles at the base of the ear. The smallest retrogradely labelled neurons in the SCG or StG lacked TH-IR but contained NPY-IR and projected almost exclusively to arterial vessels in the lateral muscle at the base of the ear. Thus, somata of sympathetic neurons projecting to cutaneous versus striated muscle vessels or to different regions of the cutaneous bed could be distinguished by a combination of location, size, and immunohistochemical profile. Consequently, regulation of blood flow within the rabbit ear is likely to involve coordination between neuronal pathways containing neurochemically and morphologically distinct populations of sympathetic neurons.
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Affiliation(s)
- J L Morris
- Department of Anatomy and Histology, Flinders University of South Australia, Adelaide, South Australia 5001, Australia.
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Abstract
This study has characterized constrictions of small cutaneous arteries in the guinea pig ear in response to electrical stimulation of the cervical sympathetic nerve (SNS) in vivo. Video microscopy and on-line image analysis were used to examine diameter changes of ear arteries (80-140 micrometers resting diameter) in anesthetized guinea pigs. Trains of 50-300 impulses, but not single pulses or short trains, produced frequency-dependent (2-20 Hz) constrictions. The purinoceptor antagonist suramin (30 microM) greatly reduced constrictions produced by exogenous ATP but did not affect constrictions produced by SNS at 10 Hz or exogenous norepinephrine. The alpha(2)-adrenoceptor antagonist yohimbine (1 microM) enhanced the peak amplitude of sympathetic constrictions at lower stimulation frequencies (1-5 Hz). The amplitude of constrictions to SNS at 10 Hz was reduced, and the latency of constrictions was increased by the alpha(1)-adrenoceptor antagonist prazosin (1 microM). Constrictions to SNS at 10 Hz remaining after prazosin treatment were reduced in amplitude by dihydroergotamine (2 microM) and were attenuated further by the neuropeptide Y Y(1)-receptor antagonist 1229U91 (0.3 microM). Thus norepinephrine and neuropeptide Y act as cotransmitters to mediate sympathetic constriction of small ear arteries at higher stimulation frequencies (10 Hz), but ATP does not seem to contribute directly to these constrictions.
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Affiliation(s)
- J L Morris
- Centre for Neuroscience and Department of Anatomy and Histology, School of Medicine, Flinders University of South Australia, Adelaide, South Australia 5001, Australia.
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Morris RS, Karande VC, Dudkiewicz A, Morris JL, Gleicher N. Octreotide is not useful for clomiphene citrate resistance in patients with polycystic ovary syndrome but may reduce the likelihood of ovarian hyperstimulation syndrome. Fertil Steril 1999; 71:452-6. [PMID: 10065781 DOI: 10.1016/s0015-0282(98)00475-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To determine whether octreotide is effective for ovulation induction in patients with polycystic ovary syndrome (PCOS) and clomiphene citrate resistance or for reduction of the risk of ovarian hyperstimulation syndrome (OHSS) with gonadotropin therapy. DESIGN Prospective, double-blind, placebo-controlled, crossover trial. SETTING Private infertility practice. PATIENT(S) Twelve patients with PCOS undergoing therapy for infertility. INTERVENTION(S) The patients were assigned randomly to receive either octreotide or placebo. Those with clomiphene citrate-resistant PCOS received clomiphene citrate, 150 mg. Patients at risk for the development of OHSS received urinary FSH for ovulation induction. MAIN OUTCOME MEASURE(S) Ovulation, pregnancy, the development of OHSS, and levels of fasting insulin, insulin-like growth factor 1, insulin-like growth factor binding proteins 1 and 3, testosterone, androstenedione, DHEAS, E2, LH, and FSH. RESULT(S) Octreotide significantly reduced levels of fasting insulin, insulin-like growth factor 1, and LH in both clomiphene citrate- and urinary FSH-stimulated cycles. Levels of insulin-like growth factor binding protein 3 were increased. Two of six clomiphene citrate-stimulated cycles reached ovulation with the use of either octreotide or placebo. In urinary FSH-stimulated cycles, patients who received octreotide had significantly lower E2 levels at the time of hCG administration and fewer mature follicles. No cases of OHSS occurred in either group. One pregnancy occurred in each group. CONCLUSION(S) Octreotide was no more effective than placebo for clomiphene citrate resistance in patients with PCOS, but it did reduce E2 levels and follicle numbers when combined with urinary FSH. Thus, octreotide may reduce the incidence of OHSS in patients with PCOS.
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Affiliation(s)
- R S Morris
- Division of Reproductive Endocrinology, Center for Human Reproduction, Chicago, Illinois 60610, USA.
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Morris JL, Cunnane TC, Hirst GD. Regional differences in sympathetic neurotransmission to cutaneous arteries in the guinea-pig isolated ear. J Auton Nerv Syst 1998; 73:115-24. [PMID: 9862386 DOI: 10.1016/s0165-1838(98)00122-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The effects of sympathetic nerve stimulation on different cutaneous arteries were examined in arteries isolated from guinea-pig ears, by measuring membrane potential changes in smooth muscle cells in response to electrical field stimulation. Resting membrane potential (RMP) was similar in proximal (main ear artery) and distal (3rd or 4th branch order) cutaneous arteries (mean -71 mV). Single stimuli evoked excitatory junction potentials (EJPs) in all arteries. The EJPs in proximal arteries were twice the amplitude, and the time constant of EJP decay was almost half the value, compared with distal cutaneous arteries. EJP amplitude was reduced by > 90% by suramin (30 microM) or alpha,beta,methylene-ATP (alpha,beta,m-ATP)(1 microM) in all proximal, and most distal arteries. Residual responses in distal arteries were resistant to tetrodotoxin. The N-type calcium channel blocker, omega-conotoxin GVIA (30 nM), reduced EJP amplitude by 70-100% in both proximal and distal arteries. Successive EJPs evoked by trains of stimuli at 1 to 5 Hz were depressed in amplitude in proximal arteries, but showed facilitation in distal arteries. EJP depression in proximal arteries was reversed to facilitation by the alpha2-adrenoceptor antagonist, yohimbine (30 nM). Trains of stimuli delivered at 10-20 Hz produced summation of EJPs and active membrane responses in 30% of proximal arteries. Active responses were never detected in distal arteries. Slow depolarizations following the EJPs were detected in most arteries after trains of stimuli, and were abolished by prazosin (0.3 microM) or omega-conotoxin GVIA (30 nM). The density of the perivascular plexus of axons innervating proximal arteries, demonstrated with catecholamine fluorescence histochemistry, was twice that in distal cutaneous arteries. These regional differences in sympathetic neurotransmission suggest that cutaneous vasoconstriction in response to thermoregulatory stimuli, which occurs predominantly in distal cutaneous segments, is likely to be qualitatively different from cutaneous vasoconstriction of proximal arteries in response to other physiological stimuli.
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Affiliation(s)
- J L Morris
- Department of Anatomy and Histology, Centre for Neuroscience, Flinders University of South Australia, Adelaide, Australia.
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Abstract
Coronary artery perforation is an unusual but well recognised complication of Percutaneous Transluminal Coronary Angioplasty (PTCA) and coronary atherectomy and may lead to hemopericardium and cardiac tamponade. If the perforation cannot be sealed by prolonged inflation with a perfusion balloon catheter, emergency cardiac surgery is usually necessary. This case report describes the potential use of a "covered" coronary artery stent for sealing perforations in the coronary circulation.
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Morris JL, Grasby DJ, Anderson RL, Gibbins IL. Neurochemical distinction between skeletal muscle vasodilator neurons and pelvic vasodilator neurons in guinea-pigs. J Auton Nerv Syst 1998; 71:64-8. [PMID: 9722196 DOI: 10.1016/s0165-1838(98)00056-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This study sets out to compare the combinations of potential vasodilator transmitters expressed by sympathetic and pelvic vasodilator neurons of guinea-pigs. Triple-labelling fluorescence immunohistochemistry was used to examine immunoreactivity (IR) to vasoactive intestinal peptide (VIP), nitric oxide synthase (NOS) and calcitonin gene-related peptide (CGRP) in lumbar sympathetic ganglia, and in perivascular axons supplying hindlimb skeletal muscles or pelvic viscera. Only 0.2% of VIP-IR nerve cell bodies in lumbar sympathetic ganglia (n = 4632 VIP-IR nerve cell profiles) contained NOS-IR, and one VIP-IR neuron contained CGRP-IR. The VIP-IR perivascular axons along the common and external iliac arteries, femoral artery and arteries to hindlimb muscles lacked NOS-IR and CGRP-IR. In contrast, all VIP-IR perivascular axons projecting from pelvic ganglia to the main uterine artery, and half of the VIP-IR axons along the internal iliac artery, contained NOS-IR and CGRP-IR. Thus, the neurochemical content of sympathetic vasodilator neurons to skeletal muscle arteries was clearly distinguishable from that of pelvic vasodilator neurons to the uterine vasculature. Furthermore, the autonomic dilation in each vascular bed is likely to be qualitatively different, and matched to the functional requirements of each target organ.
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Affiliation(s)
- J L Morris
- Centre for Neuroscience and Department of Anatomy and Histology, Flinders University of South Australia, Adelaide, Australia.
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Abstract
We have combined retrograde axonal tracing using Fast Blue and Dil, with immunohistochemistry, to estimate the maximum size of peripheral fields of identified sympathetic vasoconstrictor neurons projecting to guinea-pig ear tips. Many neurons in the superior cervical ganglia were labelled with both Fast Blue and Dil after dye injections up to 7 mm apart. Few neurons were labelled when dye injections were 8-10 mm apart. Neurons labelled with both Dil and Fast Blue after dye injections 5-7 mm apart had, on average, larger somata (436 +/- 84 microm2, mean +/- SEM, n = 47) than neurons labelled with Dil only (388 +/- 11 microm2, n = 147). Typically, 50-100 neurons innervated a region of vasculature 1 mm in diameter. We conclude that sympathetic vasoconstrictor neurons branch widely before converging on to their target blood vessels. Progressive recruitment of vasoconstrictor neurons with increasing field size would provide an efficient mechanism for graded neural control of the circulation.
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Affiliation(s)
- I L Gibbins
- Department of Anatomy and Histology, Flinders University of South Australia, Adelaide, Australia.
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Abstract
Here we describe the localization of a potent vasodilator, calcitonin gene-related peptide (CGRP), in pelvic autonomic neurons containing four other inhibitory transmitters: vasoactive intestinal peptide (VIP), neuropeptide Y, nitric oxide and acetylcholine. These neurons mediate endothelium-independent vasodilation by releasing nitric oxide and one or more neuropeptides. Sixty percent of nerve cell bodies in guinea-pig paracervical ganglia with immunoreactivity (IR) for VIP, choline acetyltransferase (ChAT) and nitric oxide synthase (NOS), also contained IR for CGRP. Furthermore, many VIP-IR varicose nerve terminals at the adventitia-medial junction of the guinea-pig uterine artery contained IR for CGRP, ChAT and NOS. Both alpha-hCGRP and beta-hCGRP were potent dilators of the uterine artery (pD2 values 8.1, 8.3, respectively), but 1 microM hCGRP(8-37) did not antagonize dilations produced by either agonist. Dilations produced by alpha-hCGRP were unaffected by removal of the endothelium. Taken together with results of our previous studies, we propose that CGRP can contribute directly to autonomic vasodilation, possibly via CGRP2 receptors on smooth muscle cells, and that CGRP is the fifth inhibitory transmitter co-existing in pelvic vasodilator neurons.
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Affiliation(s)
- R L Anderson
- Department of Anatomy and Histology, School of Medicine, Flinders University of South Australia, Adelaide, Australia
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Morris JL, Kondo M, Gibbins IL. Selective innervation of different target tissues in guinea-pig cranial exocrine glands by sub-populations of parasympathetic and sympathetic neurons. J Auton Nerv Syst 1997; 66:75-86. [PMID: 9334996 DOI: 10.1016/s0165-1838(97)00070-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study has used multiple-labelling immunohistochemistry and quantitative analysis to examine the projections of subpopulations of parasympathetic and sympathetic neurons to different vascular and secretory structures in five cranial exocrine glands of guinea-pigs. Multiple subpopulations of parasympathetic axons, identified by immunoreactivity (IR) for various combinations of peptides, innervated arteries, arterioles, ducts and acini in sublingual, submandibular, parotid, lacrimal and zygomatic glands, although axons were absent from ducts in the parotid gland. Most parasympathetic axons contained IR for vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY), with or without enkephalin (Enk). The proportion of parasympathetic axons that contained Enk-IR varied greatly between target tissues and glands: Enk-IR was more common in axons supplying secretory ducts, acini and arterioles than in axons innervating more proximal arteries; Enk-IR was less common in axons supplying the lacrimal gland than axons supplying the submandibular, lacrimal and zygomatic glands. Sympathetic axons with IR for tyrosine hydroxylase (TH) innervated arterial vessels in all glands, but innervated secretory structures only in the salivary glands. Sympathetic axons supplying proximal arterial segments often contained NPY-IR and sometimes also contained IR for dynorphin. Dynorphin-IR was more common in axons in the parotid, lacrimal and zygomatic glands than in the sublingual and submandibular glands. In contrast, axons supplying arterioles, ducts and acini lacked peptide IR. These results indicate that neuronal pathways regulating proximal arteries in cranial exocrine glands are different from the neuronal pathways regulating arterioles and acini, and may be different from neurons projecting to proximal secretory ducts. Furthermore, the peptides enkephalin, NPY and dynorphin are likely to make variable contributions to autonomic neurotransmission in different arterial segments and in different cranial exocrine glands.
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Affiliation(s)
- J L Morris
- Centre for Neuroscience, School of Medicine, Flinders University of South Australia, Adelaide, Australia.
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Grasby DJ, Gibbins IL, Morris JL. Projections of sympathetic non-noradrenergic neurons to skeletal muscle arteries in guinea-pig limbs vary with the metabolic character of muscles. J Vasc Res 1997; 34:351-64. [PMID: 9349729 DOI: 10.1159/000159244] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
This study set out to examine in detail the distribution of axons of sympathetic non-noradrenergic neurons innervating the arterial bed in skeletal muscles of the forelimb and hindlimb of guinea-pigs. The distribution of non-noradrenergic axons with immunoreactivity to vasoactive intestinal peptide (VIP) was examined in limb muscles of different histochemical character. The immunohistochemical demonstration of myosin heavy chain from fast-twitch muscle, and the histochemical demonstration of adenosine triphosphatase and succinic dehydrogenase, were used to determine the muscle fibre profile of 6 different limb muscles. Muscles included the oxidative type I muscle fibre-rich accessory semimembranosus muscle, the predominantly glycolytic type II muscle fibre-rich cranial gracilis and biceps brachii muscles and the plantaris, gastrocnemius medial head and triceps brachii long head of mixed muscle fibre composition. The frequency with which the VIP-immunoreactive (VIP-IR) axons innervated intramuscular arterial vessels was compared between categories of muscles defined by their muscle fibre profile. This study demonstrated that the projection of non-noradrenergic sympathetic neurons to skeletal muscle vasculature was widespread in guinea-pig limb muscles, but that it was not uniform. VIP-IR axons were more likely to innervate the arterial vasculature of muscles with a high proportion of type I and/or oxidative muscle fibres than of muscles with a large proportion of type IIb muscle fibres. This relationship between the distribution of sympathetic non-noradrenergic axons and the metabolic characteristics of muscle suggests that these presumed vasodilator neurons have an important role in matching blood flow to the particular metabolic demands of different limb muscles.
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Affiliation(s)
- D J Grasby
- Department of Anatomy and Histology, and Centre for Neuroscience, School of Medicine, Flinders University of South Australia, Adelaide.
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Ramsdale DR, Morris JL. Angioplasty has been shown to have benefits over thrombolytic treatment. BMJ 1997; 314:515-6. [PMID: 9056814 PMCID: PMC2126015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Zaman AG, Morris JL, Smyllie JH, Lindsay SJ, Cowan JC. Late potentials in the thrombolytic era: time for reevaluation? J Am Coll Cardiol 1997; 29:224-5. [PMID: 8996322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Anderson RL, Gibbins IL, Morris JL. Non-noradrenergic sympathetic neurons project to extramuscular feed arteries and proximal intramuscular arteries of skeletal muscles in guinea-pig hindlimbs. J Auton Nerv Syst 1996; 61:51-60. [PMID: 8912254 DOI: 10.1016/0165-1838(96)00042-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This study set out to examine the non-noradrenergic sympathetic innervation of extramuscular and intramuscular arterial vessels supplying hindlimb muscles of guinea-pigs, using multiple-labelling fluorescence immunohistochemistry. Non-noradrenergic axons, identified by their immunoreactivity (IR) to vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY), innervated nearly all (> or = 88%) extramuscular feed arteries supplying muscles of the medial thigh. The distribution of non-noradrenergic axons along extramuscular feed arteries was often patchy, with increased density near some branch points. The density of axons with VIP-IR and NPY-IR at the adventitia-medial junction of the largest extramuscular arteries was similar to the density of noradrenergic axons identified by IR to tyrosine hydroxylase (TH) and NPY. The proportion of arterial vessels innervated by VIP-IR axons decreased in more distal, intramuscular arterial segments, and when present, the VIP-IR axons were fewer in number than TH-IR axons innervating the same segments. Distal arterioles (< 20 microns diameter) were never innervated by VIP-IR axons, but always by TH-Ir axons. The non-noradrenergic sympathetic neurons are almost certainly vasodilator neurons. The prominent innervation of extramuscular feed arteries by sympathetic non-noradrenergic neurons has not been reported previously, even in cats and dogs where there is good physiological evidence for a sympathetic vasodilator response in skeletal muscles. The present morphological results provide compelling reasons for re-evaluating the functional role of sympathetic vasodilation in skeletal muscles of rodents, particularly in relation to the role of feed arteries in neural regulation of muscle blood flow.
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Affiliation(s)
- R L Anderson
- Department of Anatomy and Histology, School of Medicine, Flinders University of South Australia, Adelaide, Australia
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Gibbins IL, Matthew SE, Bridgman N, Morris JL. Sympathetic vasoconstrictor neurons projecting from the guinea-pig superior cervical ganglion to cutaneous or skeletal muscle vascular beds can be distinguished by soma size. Neurosci Lett 1996; 213:197-200. [PMID: 8873148 DOI: 10.1016/0304-3940(96)12885-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have used a combination of retrograde axonal tracing and intracellular dye injections to determine the soma size of sympathetic vasoconstrictor neurons projecting from the superior cervical ganglion to the cutaneous vascular bed of the eartips, or to the vascular beds of the masseter muscle, of guinea-pigs. Neurons projecting to vasculature of the masseter muscle had a cross-sectional area of 956 +/- 295 microns2 (mean +/- SD; n = 45 cells) and were significantly larger than neurons projecting to the vasculature of the eartip skin (mean cross-sectional area +/- SD, 604 +/- 251 microns2; n = 39 cells). These results are consistent with physiological observations showing that muscle vasoconstrictor neurons have faster conduction velocities than cutaneous vasoconstrictor neurons. Furthermore, they suggest that muscle vasoconstrictor neurons may innervate a larger volume of vasculature compared with cutaneous vasoconstrictor neurons.
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Affiliation(s)
- I L Gibbins
- Department of Anatomy and Histology, School of Medicine, Flinders University of South Australia, Adelaide, Australia.
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Hutton JT, Koller WC, Ahlskog JE, Pahwa R, Hurtig HI, Stern MB, Hiner BC, Lieberman A, Pfeiffer RF, Rodnitzky RL, Waters CH, Muenter MD, Adler CH, Morris JL. Multicenter, placebo-controlled trial of cabergoline taken once daily in the treatment of Parkinson's disease. Neurology 1996; 46:1062-5. [PMID: 8780092 DOI: 10.1212/wnl.46.4.1062] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Cabergoline is a dopaminergic agonist relatively specific for the D2 receptor and much longer-acting than other dopamine agonists. We conducted a randomized, placebo-controlled, double-blind study of cabergoline in 188 levodopa/carbidopa-treated patients with suboptimally controlled Parkinson's disease (PD). The cabergoline patients had significantly better Activities of Daily Living (p = 0.032) and Motor Examination (p = 0.031) scores at the conclusion of the trial compared with the placebo group. The daily levodopa dose for the cabergoline patients decreased 18% compared with a 3% reduction for the placebo group (p < 0.001). The amount of time in the "on" state increased more in the cabergoline group (p = 0.022). The side-effect was similar to that seen with other dopamine agonists, and cabergoline was generally well tolerated. We conclude that cabergoline is an effective adjunct to levodopa for the treatment of PD.
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Affiliation(s)
- J T Hutton
- Neurology Research and Education Center, St. Mary of the Plains Hospital, Lubbock, TX 79410, USA
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Abstract
We set out to determine the projections of the major immunohistochemically-defined populations of intrinsic cardiac neurons to different target tissues within the guinea-pig heart. Ultrastructural studies, and immunoreactivity to the neuronal marker, neuron-specific enolase, suggested that the number of axons of intrinsic neurons in most regions of the heart was low when compared with the populations of axons projecting from extrinsic sensory and sympathetic ganglia. Multiple-labelling immunofluorescence was used to demonstrate the terminals of the major populations of peptide-containing intrinsic neurons. The intrinsic nature of peptide-containing axons was confirmed by long-term organotypic culture of cardiac tissue, which resulted in degeneration of axons of extrinsic neurons. The relative density and peptide content of intrinsic axons throughout the heart was not consistent with the relative proportions of peptide-containing intracardiac nerve cell bodies observed previously. The most commonly-encountered axons contained immunoreactivity (IR) to vasoactive intestinal peptide (VIP) alone, although nerve cell bodies with VIP constituted less than 5% of the total population of intrinsic neurons. Populations of axons containing IR to somatostatin alone, somatostatin and substance P, neuropeptide Y (NPY) alone, somatostatin and NPY, or VIP and NPY, also were observed. Intrinsic axons containing substance P-IR were very rare, much more so than would be predicted from the peptide content of intrinsic nerve cell bodies. The regions of the heart with the most dense innervation by axons of intrinsic neurons were the cardiac valves, the atrio-ventricular node and the sino-atrial node. Each of these targets was innervated by several populations of peptide-containing axons. Thus, each population of peptide-containing intrinsic neurons projected to a variety of target tissues within the heart. One possible interpretation of these results is that immunohistochemically-distinct populations of intrinsic neurons belong to different functional classes of neurons (sensory neurons, interneurons, final motor neurons), each of which innervates many regions of the heart.
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Affiliation(s)
- P A Steele
- Department of Physiology, University of Adelaide, S.A., Australia.
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