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Colom-Cadena M, Toombs J, Simzer E, Holt K, McGeachan R, Tulloch J, Jackson RJ, Catterson JH, Spires-Jones MP, Rose J, Waybright L, Caggiano AO, King D, Gobbo F, Davies C, Hooley M, Dunnett S, Tempelaar R, Meftah S, Tzioras M, Hamby ME, Izzo NJ, Catalano SM, Durrant CS, Smith C, Dando O, Spires-Jones TL. Transmembrane protein 97 is a potential synaptic amyloid beta receptor in human Alzheimer's disease. Acta Neuropathol 2024; 147:32. [PMID: 38319380 PMCID: PMC10847197 DOI: 10.1007/s00401-023-02679-6] [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: 08/09/2023] [Revised: 12/24/2023] [Accepted: 12/24/2023] [Indexed: 02/07/2024]
Abstract
Synapse loss correlates with cognitive decline in Alzheimer's disease, and soluble oligomeric amyloid beta (Aβ) is implicated in synaptic dysfunction and loss. An important knowledge gap is the lack of understanding of how Aβ leads to synapse degeneration. In particular, there has been difficulty in determining whether there is a synaptic receptor that binds Aβ and mediates toxicity. While many candidates have been observed in model systems, their relevance to human AD brain remains unknown. This is in part due to methodological limitations preventing visualization of Aβ binding at individual synapses. To overcome this limitation, we combined two high resolution microscopy techniques: array tomography and Förster resonance energy transfer (FRET) to image over 1 million individual synaptic terminals in temporal cortex from AD (n = 11) and control cases (n = 9). Within presynapses and post-synaptic densities, oligomeric Aβ generates a FRET signal with transmembrane protein 97. Further, Aβ generates a FRET signal with cellular prion protein, and post-synaptic density 95 within post synapses. Transmembrane protein 97 is also present in a higher proportion of post synapses in Alzheimer's brain compared to controls. We inhibited Aβ/transmembrane protein 97 interaction in a mouse model of amyloidopathy by treating with the allosteric modulator CT1812. CT1812 drug concentration correlated negatively with synaptic FRET signal between transmembrane protein 97 and Aβ. In human-induced pluripotent stem cell derived neurons, transmembrane protein 97 is present in synapses and colocalizes with Aβ when neurons are challenged with human Alzheimer's brain homogenate. Transcriptional changes are induced by Aβ including changes in genes involved in neurodegeneration and neuroinflammation. CT1812 treatment of these neurons caused changes in gene sets involved in synaptic function. These data support a role for transmembrane protein 97 in the synaptic binding of Aβ in human Alzheimer's disease brain where it may mediate synaptotoxicity.
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Affiliation(s)
- Martí Colom-Cadena
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Jamie Toombs
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Elizabeth Simzer
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Kristjan Holt
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Robert McGeachan
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Jane Tulloch
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Rosemary J Jackson
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
- MassGeneral Institute for Neurodegenerative Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - James H Catterson
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Maxwell P Spires-Jones
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Jamie Rose
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | | | | | - Declan King
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Francesco Gobbo
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Caitlin Davies
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Monique Hooley
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Sophie Dunnett
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Robert Tempelaar
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Soraya Meftah
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Makis Tzioras
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
- Scottish Brain Sciences, Edinburgh, EH12 9DQ, UK
| | - Mary E Hamby
- Cognition Therapeutics Inc., Pittsburgh, PA, 15203, USA
| | | | | | - Claire S Durrant
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Colin Smith
- Centre for Clinical Brain Sciences and Sudden Death Brain Bank, University of Edinburgh, Edinburgh, EH16 4HB, UK
| | - Owen Dando
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Tara L Spires-Jones
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK.
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van Dyck CH, Mecca AP, O'Dell RS, Bartlett HH, Diepenbrock NG, Huang Y, Hamby ME, Grundman M, Catalano SM, Caggiano AO, Carson RE. A pilot study to evaluate the effect of CT1812 treatment on synaptic density and other biomarkers in Alzheimer's disease. Alzheimers Res Ther 2024; 16:20. [PMID: 38273408 PMCID: PMC10809445 DOI: 10.1186/s13195-024-01382-2] [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: 08/04/2023] [Accepted: 01/01/2024] [Indexed: 01/27/2024]
Abstract
BACKGROUND Effective, disease-modifying therapeutics for the treatment of Alzheimer's disease (AD) remain a large unmet need. Extensive evidence suggests that amyloid beta (Aβ) is central to AD pathophysiology, and Aβ oligomers are among the most toxic forms of Aβ. CT1812 is a novel brain penetrant sigma-2 receptor ligand that interferes with the binding of Aβ oligomers to neurons. Preclinical studies of CT1812 have demonstrated its ability to displace Aβ oligomers from neurons, restore synapses in cell cultures, and improve cognitive measures in mouse models of AD. CT1812 was found to be generally safe and well tolerated in a placebo-controlled phase 1 clinical trial in healthy volunteers and phase 1a/2 clinical trials in patients with mild to moderate dementia due to AD. The unique objective of this study was to incorporate synaptic positron emission tomography (PET) imaging as an outcome measure for CT1812 in AD patients. METHODS The present phase 1/2 study was a randomized, double-blind, placebo-controlled, parallel-group trial conducted in 23 participants with mild to moderate dementia due to AD to primarily evaluate the safety of CT1812 and secondarily its pharmacodynamic effects. Participants received either placebo or 100 mg or 300 mg per day of oral CT1812 for 24 weeks. Pharmacodynamic effects were assessed using the exploratory efficacy endpoints synaptic vesicle glycoprotein 2A (SV2A) PET, fluorodeoxyglucose (FDG) PET, volumetric MRI, cognitive clinical measures, as well as cerebrospinal fluid (CSF) biomarkers of AD pathology and synaptic degeneration. RESULTS No treatment differences relative to placebo were observed in the change from baseline at 24 weeks in either SV2A or FDG PET signal, the cognitive clinical rating scales, or in CSF biomarkers. Composite region volumetric MRI revealed a trend towards tissue preservation in participants treated with either dose of CT1812, and nominally significant differences with both doses of CT1812 compared to placebo were found in the pericentral, prefrontal, and hippocampal cortices. CT1812 was safe and well tolerated. CONCLUSIONS The safety findings of this 24-week study and the observed changes on volumetric MRI with CT1812 support its further clinical development. TRIAL REGISTRATION The clinical trial described in this manuscript is registered at clinicaltrials.gov (NCT03493282).
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Affiliation(s)
- Christopher H van Dyck
- Alzheimer's Disease Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
| | - Adam P Mecca
- Alzheimer's Disease Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Ryan S O'Dell
- Alzheimer's Disease Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Hugh H Bartlett
- Alzheimer's Disease Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Nina G Diepenbrock
- Alzheimer's Disease Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
| | - Mary E Hamby
- Cognition Therapeutics Inc., Pittsburgh, PA, USA
| | - Michael Grundman
- Global R&D Partners, LLC, San Diego, CA, USA
- Department of Neurosciences, University of California, San Diego, USA
| | | | | | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
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3
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LaBarbera KM, Sheline YI, Izzo NJ, Yuede CM, Waybright L, Yurko R, Edwards HM, Gardiner WD, Blennow K, Zetterberg H, Börjesson-Hanson A, Morgan R, Davis CS, Guttendorf RJ, Schneider LS, DeKosky S, LeVine H, Grundman M, Caggiano AO, Cirrito JR, Catalano SM, Hamby ME. A phase 1b randomized clinical trial of CT1812 to measure Aβ oligomer displacement in Alzheimer's disease using an indwelling CSF catheter. Transl Neurodegener 2023; 12:24. [PMID: 37173791 PMCID: PMC10176668 DOI: 10.1186/s40035-023-00358-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023] Open
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Henrik Zetterberg
- University of Gothenburg, Mölndal, Sweden
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | | | | | | | | | | | - Steven DeKosky
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Harry LeVine
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Michael Grundman
- Global R&D Partners, LLC, San Diego, CA, USA
- Department of Neurosciences, University of California, San Diego, USA
| | | | | | | | - Mary E Hamby
- Cognition Therapeutics Inc., Pittsburgh, PA, USA.
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4
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Lizama BN, Kahle J, Catalano SM, Caggiano AO, Grundman M, Hamby ME. Sigma-2 Receptors—From Basic Biology to Therapeutic Target: A Focus on Age-Related Degenerative Diseases. Int J Mol Sci 2023; 24:ijms24076251. [PMID: 37047224 PMCID: PMC10093856 DOI: 10.3390/ijms24076251] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/18/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
There is a large unmet medical need to develop disease-modifying treatment options for individuals with age-related degenerative diseases of the central nervous system. The sigma-2 receptor (S2R), encoded by TMEM97, is expressed in brain and retinal cells, and regulates cell functions via its co-receptor progesterone receptor membrane component 1 (PGRMC1), and through other protein–protein interactions. Studies describing functions of S2R involve the manipulation of expression or pharmacological modulation using exogenous small-molecule ligands. These studies demonstrate that S2R modulates key pathways involved in age-related diseases including autophagy, trafficking, oxidative stress, and amyloid-β and α-synuclein toxicity. Furthermore, S2R modulation can ameliorate functional deficits in cell-based and animal models of disease. This review summarizes the current evidence-based understanding of S2R biology and function, and its potential as a therapeutic target for age-related degenerative diseases of the central nervous system, including Alzheimer’s disease, α-synucleinopathies, and dry age-related macular degeneration.
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Affiliation(s)
| | | | | | | | - Michael Grundman
- Global R&D Partners, LLC., San Diego, CA 92130, USA
- Department of Neurosciences, University of California, San Diego, CA 92093, USA
| | - Mary E. Hamby
- Cognition Therapeutics, Inc., Pittsburgh, PA 15203, USA
- Correspondence:
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5
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Pandey K, Waybright L, Duong DM, Malagise E, Blennow K, Zetterberg H, Mecca AP, van Dyck CH, Caggiano AO, Seyfried NT, Hamby ME. CSF proteomics analysis to investigate the pharmacodynamic response of the S2R modulator CT1812 in Alzheimer’s disease patients from the SPARC clinical trial. Alzheimers Dement 2022. [DOI: 10.1002/alz.068166] [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: 12/24/2022]
Affiliation(s)
| | | | | | | | - Kaj Blennow
- Institute of Neuroscience & Physiology, Department of Psychiatry & Neurochemistry, The Sahlgrenska Academy, University of Gothenburg Mölndal Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg Sweden
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6
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Greenberg BM, Bowen JD, Alvarez E, Rodriguez M, Caggiano AO, Warrington AE, Zhao P, Eisen A. A double-blind, placebo-controlled, single-ascending-dose intravenous infusion study of rHIgM22 in subjects with multiple sclerosis immediately following a relapse. Mult Scler J Exp Transl Clin 2022; 8:20552173221091475. [PMID: 35496758 PMCID: PMC9052243 DOI: 10.1177/20552173221091475] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/16/2022] [Indexed: 11/30/2022] Open
Abstract
Background Recombinant human immunoglobulin M22 (rHIgM22) has promoted remyelination in animal models and was well tolerated in people with clinically stable multiple sclerosis. Objective Safety/tolerability of a single rHIgM22 dose was investigated following an acute relapse and to determine whether this enhanced CNS/CSF concentrations. Methods Adults (N = 27) with acute relapse were assigned to rHIgM22 (0.5 or 2.0 mg/kg) or placebo. Study included screening/steroid administration periods and 10 study visits over 6 months. rHIgM22 CSF concentrations were assessed on days 2 and 29. Pharmacokinetic and safety samples were taken for up to 60 days. Assessments included adverse events and other clinical measures. Brain magnetic resonance imaging was performed with/without gadolinium. Results rHIgM22 CSF levels were consistent with dose-dependent concentration on both days 2 and 29. Infusion was generally well tolerated during an acute relapse. Immunogenicity was mild. Most adverse events did not appear to be dose dependent, were mild/moderate, and were events often associated with multiple sclerosis. Conclusion Although limited by high variability and small sample size, the data suggest enhanced CNS uptake associated with a drop in CSF levels. This study demonstrated safety of an antibody directed to myelin and oligodendrocytes in the course of active demyelinating disease. Further research into rHIgM22 is warranted. ClinicalTrials.gov: NCT02398461 https://clinicaltrials.gov/ct2/show/study/NCT02398461?term=M22&draw=2&rank=8
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Affiliation(s)
| | | | | | | | | | | | - Ping Zhao
- Acorda Therapeutics, Inc, Ardsley, NY
- ONO Pharma, Rockville, MD
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7
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Schneider LS, Caggiano AO, Grundman M, DeKosky S, Morgan R, Mozzoni K, Izzo NJ, Safferstein H, Catalano S. P4‐708: CLINICAL BIOMARKER EVIDENCE FOR TARGET ENGAGEMENT, REDUCTION OF SYNAPTIC DAMAGE AND DISEASE MODIFICATION IN ALZHEIMER'S PATIENTS TREATED WITH CT1812. Alzheimers Dement 2019. [DOI: 10.1016/j.jalz.2019.09.072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Lon S. Schneider
- Keck School of Medicine at University of Southern California Los Angeles CA USA
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8
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Rosenzweig ES, Salegio EA, Liang JJ, Weber JL, Weinholtz CA, Brock JH, Moseanko R, Hawbecker S, Pender R, Cruzen CL, Iaci JF, Caggiano AO, Blight AR, Haenzi B, Huie JR, Havton LA, Nout-Lomas YS, Fawcett JW, Ferguson AR, Beattie MS, Bresnahan JC, Tuszynski MH. Chondroitinase improves anatomical and functional outcomes after primate spinal cord injury. Nat Neurosci 2019; 22:1269-1275. [PMID: 31235933 PMCID: PMC6693679 DOI: 10.1038/s41593-019-0424-1] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 05/10/2019] [Indexed: 01/07/2023]
Abstract
Inhibitory extracellular matrices form around mature neurons as perineuronal nets containing chondroitin sulfate proteoglycans (CSPGs) that limit axonal sprouting after CNS injury. The enzyme chondroitinase (Chase) degrades the inhibitory CSPGs and improves axonal sprouting and functional recovery after spinal cord injury (SCI) in rodents. We evaluated the effects of Chase in Rhesus monkeys that had undergone C7 spinal cord hemisection. Four weeks after hemisection, multiple intraparenchymal Chase injections targeted spinal cord circuits controlling hand function below the lesion. Hand function improved significantly in Chase-treated monkeys relative to vehicle-injected controls. Moreover, Chase significantly increased corticospinal axon growth and the number of synapses formed by corticospinal terminals in gray matter caudal to the lesion. No detrimental effects were detected. This approach appears to merit clinical translation in SCI.
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Affiliation(s)
- Ephron S Rosenzweig
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Ernesto A Salegio
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Justine J Liang
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Janet L Weber
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Chase A Weinholtz
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - John H Brock
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA.,Veterans Administration Medical Center, La Jolla, CA, USA
| | - Rod Moseanko
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Stephanie Hawbecker
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Roger Pender
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Christina L Cruzen
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | | | | | | | | | - J Russell Huie
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Leif A Havton
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yvette S Nout-Lomas
- College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | | | - Adam R Ferguson
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Michael S Beattie
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Jacqueline C Bresnahan
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Mark H Tuszynski
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA. .,Veterans Administration Medical Center, La Jolla, CA, USA.
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9
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Mosedale M, Button D, Jackson JP, Freeman KM, Brouwer KR, Caggiano AO, Eisen A, Iaci JF, Parry TJ, Stanulis R, Srinivas M, Watkins PB. Transient Changes in Hepatic Physiology That Alter Bilirubin and Bile Acid Transport May Explain Elevations in Liver Chemistries Observed in Clinical Trials of GGF2 (Cimaglermin Alfa). Toxicol Sci 2019; 161:401-411. [PMID: 29069498 DOI: 10.1093/toxsci/kfx222] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
GGF2 is a recombinant human neuregulin-1β in development for chronic heart failure. Phase 1 clinical trials of GGF2 were put on hold when transient elevations in serum aminotransferases and total bilirubin were observed in 2 of 43 subjects who received single doses of GGF2 at 1.5 or 0.378 mg/kg. However, aminotransferase elevations were modest and not typical of liver injury sufficient to result in elevated serum bilirubin. Cynomolgus monkeys administered a single 15 mg/kg dose of GGF2 had similar transient elevations in serum aminotransferases and bilirubin as well as transient elevations in serum bile acids. However, no hepatocellular necrosis was observed in liver biopsies obtained during peak elevations. When sandwich-cultured human hepatocytes were treated with GGF2 for up to 72 h at concentrations approximately 0.8-fold average plasma Cmax for the 0.378 mg/kg dose, no cytotoxicity was observed. Gene expression profiling identified approximately 50% reductions in mRNAs coding for bilirubin transporters and bile acid conjugating enzymes, as well as changes in expression of additional genes mimicking the interleukin-6-mediated acute phase response. Similar gene expression changes were observed in GGF2-treated HepG2 cells and primary monkey hepatocytes. Additional studies conducted in sandwich-cultured human hepatocytes revealed a transient and GGF2 concentration-dependent decrease in hepatocyte bile acid content and biliary clearance of taurocholate without affecting biliary taurocholate efflux. Taken together, these data suggest that GGF2 does not cause significant hepatocellular death, but transiently modifies hepatic handling of bilirubin and bile acids, effects that may account for the elevations in serum bilirubin observed in the clinical trial subjects.
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Affiliation(s)
- Merrie Mosedale
- Institute for Drug Safety Sciences, University of North Carolina at Chapel Hill, Research Triangle Park, North Carolina 27709.,Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, Chapel Hill, North Carolina 27599
| | | | | | | | | | | | | | | | - Tom J Parry
- Acorda Therapeutics, Ardsley, New York 10502
| | | | | | - Paul B Watkins
- Institute for Drug Safety Sciences, University of North Carolina at Chapel Hill, Research Triangle Park, North Carolina 27709.,Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, Chapel Hill, North Carolina 27599
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10
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Cui C, Wang J, Mullin AP, Caggiano AO, Parry TJ, Colburn RW, Pavlopoulos E. The antibody rHIgM22 facilitates hippocampal remyelination and ameliorates memory deficits in the cuprizone mouse model of demyelination. Brain Res 2018; 1694:73-86. [DOI: 10.1016/j.brainres.2018.05.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 05/13/2018] [Accepted: 05/14/2018] [Indexed: 12/26/2022]
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11
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Caggiano AO, Iaci JF, Wagner AE, Franklin R. Abstract TMP33: TXA302 Promotes Permanent Functional Recovery With Delivery Initiated Up to 4 Weeks After Stroke in Multiple Rodent Models. Stroke 2018. [DOI: 10.1161/str.49.suppl_1.tmp33] [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: 11/16/2022]
Abstract
Introduction:
TXA302 is a proprietary analogue of angiotensin 1-7 (Ang1-7). Previous studies have shown that intracerebroventricular administration of Ang1-7 as a pre-treatment to experimental occlusive rodent stroke resulted in improved neurological function, decreased infarct volume, enhanced cerebral blood flow and decreased inflammation. Here, systemic administration of TXA302 was evaluated with treatment delayed up to 4 weeks to assess the potential of TXA302 to promote recovery in chronic stroke.
Methods and Results:
Four independent studies were conducted in the rat transient (2 hour) and permanent middle cerebral artery occlusion (MCAO) models. Daily subcutaneous delivery of TXA302 or vehicle was started either 24 hours or 4 weeks after MCAO and continued for 4, 6 or 8 weeks. Treatment was started at 4 weeks to assess the ability of TXA302 to promote recovery independent of neuroprotection and to model the chronic phase of the injury. Two of the studies employed a dose range of TXA302 from 1 to 500 μg/kg and two studies had a washout period of 4 weeks after the completion of dosing to assess the permanence of the recovery effect. Sensorimotor recovery was measured by limb placing, stepping, and body swing tests along with composite neurological scoring. Cerebral blood flow (CBF) was evaluated by doppler ultrasonography. All studies were conducted in a blinded fashion and recovery of treated animals was compared to vehicle by repeated measures ANOVA with corrections for multiple comparisons. TXA302 treatment resulted in significant, robust and permanent dose-responsive improvements in neurological function and CBF compared to vehicle treated animals.
Conclusions:
The ability to delay treatment for 4 weeks suggests the changes are not attributable to neuroprotection. Furthermore, this wide therapeutic window enhances translational potential as clinical trials can be conducted without confounding factors of treating, stabilizing and assessing baseline functional measures in acute stroke patients. Ongoing studies are exploring the potential of TXA302 to enhance endogenous remodeling through angiogenesis and neural plasticity. Non-clinical studies and manufacturing development are underway to enable an IND for stroke recovery.
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12
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Eisen A, Greenberg BM, Bowen JD, Arnold DL, Caggiano AO. A double-blind, placebo-controlled, single ascending-dose study of remyelinating antibody rHIgM22 in people with multiple sclerosis. Mult Scler J Exp Transl Clin 2017; 3:2055217317743097. [PMID: 29348926 PMCID: PMC5768281 DOI: 10.1177/2055217317743097] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/12/2017] [Accepted: 10/09/2017] [Indexed: 11/15/2022] Open
Abstract
Objective The objective of this paper is to assess, in individuals with clinically stable multiple sclerosis (MS), the safety, tolerability, pharmacokinetics (PK) and exploratory pharmacodynamics of the monoclonal recombinant human antibody IgM22 (rHIgM22). Methods Seventy-two adults with stable MS were enrolled in a double-blind, randomized, placebo-controlled, single ascending-dose, Phase 1 trial examining rHIgM22 from 0.025 to 2.0 mg/kg. Assessments included MRI, MR spectroscopy, plasma PK, and changes in clinical status, laboratory values and adverse events for three months. The final cohort had additional clinical, ophthalmologic, CSF collection and exploratory biomarker evaluations. Participants were monitored for six months. Results rHIgM22 was well tolerated with no clinically significant safety signals. Noncompartmental PK modeling demonstrated linear dose-proportionality both of Cmax and AUC0–Last. The steady-state apparent volume of distribution of approximately 58 ml/kg suggested primarily vascular compartmentalization. CSF:plasma rHIgM22 concentration increased from 0.003% on Day 2 for both 1.0 and 2.0 mg/kg to 0.056% and 0.586% for 1.0 and 2.0 mg/kg, respectively, on Day 29. No statistically significant treatment-related changes were observed in exploratory pharmacodynamic outcome measures included for the 21 participants of the extension cohort. Conclusions Single doses of rHIgM22 were well tolerated and exhibited linear PK, and antibody was detected in the CSF.
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Affiliation(s)
| | | | | | - Douglas L Arnold
- NeuroRx Research, Montreal, QC, Canada.,Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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13
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Huang Z, Sawyer DB, Troy EL, McEwen C, Cleator JH, Murphy A, Caggiano AO, Eisen A, Parry TJ. Species-specific effects of neuregulin-1β (cimaglermin alfa) on glucose handling in animal models and humans with heart failure. Toxicol Appl Pharmacol 2017; 332:92-99. [PMID: 28780372 DOI: 10.1016/j.taap.2017.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 07/05/2017] [Accepted: 08/01/2017] [Indexed: 10/19/2022]
Abstract
Neuregulin-1β is a member of the neuregulin family of growth factors and is critically important for normal development and functioning of the heart and brain. A recombinant version of neuregulin-1β, cimaglermin alfa (also known as glial growth factor 2 or GGF2) is being investigated as a possible therapy for heart failure. Previous studies suggest that neuregulin-1β stimulation of skeletal muscle increases glucose uptake and, specifically, sufficient doses of cimaglermin alfa acutely produce hypoglycemia in pigs. Since acute hypoglycemia could be a safety concern, blood glucose changes in the above pig study were further investigated. In addition, basal glucose and glucose disposal were investigated in mice. Finally, as part of standard clinical chemistry profiling in a single ascending-dose human safety study, blood glucose levels were evaluated in patients with heart failure after cimaglermin alfa treatment. A single intravenous injection of cimaglermin alfa at doses of 0.8mg/kg and 2.6mg/kg in mice resulted in a transient reduction of blood glucose concentrations of approximately 20% and 34%, respectively, at 2h after the treatment compared to pre-treatment levels. Similar results were observed in diabetic mice. Treatment with cimaglermin alfa also increased blood glucose disposal following oral challenge in mice. However, no significant alterations in blood glucose concentrations were found in human heart failure patients at 0.5 and 2h after treatment with cimaglermin alfa over an equivalent human dose range, based on body surface area. Taken together, these data indicate strong species differences in blood glucose handling after cimaglermin alfa treatment, and particularly do not indicate that this phenomenon should affect human subjects.
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Affiliation(s)
- Zhihong Huang
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Douglas B Sawyer
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, 2220 Pierce Avenue, Nashville, TN 37232, USA
| | - Erika L Troy
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA
| | - Corissa McEwen
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA
| | - John H Cleator
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, 2220 Pierce Avenue, Nashville, TN 37232, USA
| | - Abigail Murphy
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, 2220 Pierce Avenue, Nashville, TN 37232, USA
| | - Anthony O Caggiano
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA
| | - Andrew Eisen
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA
| | - Tom J Parry
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
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14
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Mullin AP, Cui C, Wang Y, Wang J, Troy E, Caggiano AO, Parry TJ, Colburn RW, Pavlopoulos E. rHIgM22 enhances remyelination in the brain of the cuprizone mouse model of demyelination. Neurobiol Dis 2017; 105:142-155. [DOI: 10.1016/j.nbd.2017.05.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 05/04/2017] [Accepted: 05/29/2017] [Indexed: 02/02/2023] Open
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15
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Ganguly A, McEwen C, Troy EL, Colburn RW, Caggiano AO, Schallert TJ, Parry TJ. Recovery of sensorimotor function following sciatic nerve injury across multiple rat strains. J Neurosci Methods 2017; 275:25-32. [DOI: 10.1016/j.jneumeth.2016.10.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 10/25/2016] [Accepted: 10/28/2016] [Indexed: 12/20/2022]
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16
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Parry TJ, Ganguly A, Troy EL, Luis Guerrero J, Iaci JF, Srinivas M, Vecchione AM, Button DC, Hackett CS, Zolty R, Sawyer DB, Caggiano AO. Effects of neuregulin GGF2 (cimaglermin alfa) dose and treatment frequency on left ventricular function in rats following myocardial infarction. Eur J Pharmacol 2016; 796:76-89. [PMID: 27993643 DOI: 10.1016/j.ejphar.2016.12.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [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: 07/11/2016] [Revised: 12/14/2016] [Accepted: 12/15/2016] [Indexed: 11/17/2022]
Abstract
Neuregulins are important growth factors involved in cardiac development and response to stress. Certain isoforms and fragments of neuregulin have been found to be cardioprotective. The effects of a full-length neuregulin-1β isoform, glial growth factor 2 (GGF2; USAN/INN; also called cimaglermin) were investigated in vitro. Various dosing regimens were then evaluated for their effects on left ventricular (LV) function in rats with surgically-induced myocardial infarction. In vitro, GGF2 bound with high affinity to erythroblastic leukemia viral oncogene (ErbB) 4 receptors, potently promoted Akt phosphorylation, as well as reduced cell death following doxorubicin exposure in HL1 cells. Daily GGF2 treatment beginning 7-14 days after left anterior descending coronary artery ligation produced improvements in LV ejection fraction and other measures of LV function and morphology. The improvements in LV function (e.g. 10% point increase in absolute LV ejection fraction) with GGF2 were dose-dependent. LV performance was substantially improved when GGF2 treatment was delivered infrequently, despite a serum half-life of less than 2h and could be maintained for more than 10 months with treatment once weekly or once every 2 weeks. These studies confirm previous findings that GGF2 may improve contractile performance in the failing rat heart and that infrequent exposure to GGF2 may improve LV function and impact remodeling in the failing myocardium. GGF2 is now being developed for the treatment of heart failure in humans.
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Affiliation(s)
- Tom J Parry
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Anindita Ganguly
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Erika L Troy
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - J Luis Guerrero
- Massachusetts General Hospital, 55 Fruit St, Boston, MA 02114, USA.
| | - Jennifer F Iaci
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Maya Srinivas
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Andrea M Vecchione
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Donald C Button
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Craig S Hackett
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
| | - Ronald Zolty
- University of Nebraska Medical Center, 982265 S 42nd St & Emile St, Omaha, NE 68198, USA.
| | | | - Anthony O Caggiano
- Acorda Therapeutics, Inc., 420 Saw Mill River Rd, Ardsley, NY 10502, USA.
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17
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Streijger F, Lee JH, Manouchehri N, Okon EB, Tigchelaar S, Anderson LM, Dekaban GA, Rudko DA, Menon RS, Iaci JF, Button DC, Vecchione AM, Konovalov A, Sarmiere PD, Ung C, Caggiano AO, Kwon BK. The Evaluation of Magnesium Chloride within a Polyethylene Glycol Formulation in a Porcine Model of Acute Spinal Cord Injury. J Neurotrauma 2016; 33:2202-2216. [DOI: 10.1089/neu.2016.4439] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Femke Streijger
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
| | - Jae H.T. Lee
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
| | - Neda Manouchehri
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
| | - Elena B. Okon
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
| | - Seth Tigchelaar
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
| | - Lisa M. Anderson
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
| | - Greg A. Dekaban
- Robarts Research Institute, Western University, London, Ontario, Canada
| | - David A. Rudko
- Brain Imaging Center, Montreal Neurological Hospital and Institute, Montreal, Quebec, Canada
| | - Ravi S. Menon
- Center for Functional and Metabolic Mapping, the University of Western Ontario, London, Ontario, Canada
| | | | | | | | | | | | - Chi Ung
- Acorda Therapeutics Inc., Ardsley, New York
| | | | - Brian K. Kwon
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
- Department of Orthopedics, Vancouver Spine Surgery Institute, University of British Columbia, Blusson Spinal Cord Center, Vancouver, British Columbia, Canada
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18
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Lenihan DJ, Anderson SA, Lenneman CG, Brittain E, Muldowney JA, Mendes L, Zhao PZ, Iaci J, Frohwein S, Zolty R, Eisen A, Sawyer DB, Caggiano AO. A Phase I, Single Ascending Dose Study of Cimaglermin Alfa (Neuregulin 1β3) in Patients With Systolic Dysfunction and Heart Failure. JACC Basic Transl Sci 2016; 1:576-586. [PMID: 30167542 PMCID: PMC6113538 DOI: 10.1016/j.jacbts.2016.09.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 01/03/2023]
Abstract
A first-in-human, phase 1, double blind, placebo-controlled, single ascending dose study examined the safety, tolerability, and exploratory efficacy of intravenous infusion of a recombinant growth factor, cimaglermin alfa, in patients with heart failure and left ventricular systolic dysfunction (LVSD). In these patients on optimal guideline-directed medical therapy, cimaglermin treatment was generally tolerated except for transient nausea and headache and a dose-limiting toxicity was noted at the highest planned dose. There was a dose-dependent improvement in left ventricular ejection fraction lasting 90 days following infusion. Thus, cimaglermin is a potential therapy to enhance cardiac function in LVSD and warrants further investigation.
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Key Words
- AE, adverse event
- AUC, area under the curve
- DLT, dose-limiting toxicity
- GGF, glial growth factor
- HF, heart failure
- LVEF, left ventricular ejection fraction
- LVSD, left ventricular systolic dysfunction
- NRG, neuregulin
- NYHA, New York Heart Association functional class
- TEAE, treatment-emergent adverse event
- cardiac repair
- growth factor
- neuregulin
- systolic dysfunction
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Affiliation(s)
- Daniel J. Lenihan
- Division of Cardiovascular Medicine, Vanderbilt University, Nashville, Tennessee
| | - Sarah A. Anderson
- Division of Cardiovascular Medicine, Vanderbilt University, Nashville, Tennessee
| | | | - Evan Brittain
- Division of Cardiovascular Medicine, Vanderbilt University, Nashville, Tennessee
| | - James A.S. Muldowney
- Division of Cardiovascular Medicine, Vanderbilt University, Nashville, Tennessee
| | - Lisa Mendes
- Division of Cardiovascular Medicine, Vanderbilt University, Nashville, Tennessee
| | | | | | - Stephen Frohwein
- Emory Heart and Vascular Center at Emory Saint Joseph’s, Atlanta, Georgia
| | - Ronald Zolty
- University of Nebraska Medical Center, Omaha, Nebraska
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19
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Huang Z, Filipovic Z, Mp N, Ung C, Troy EL, Colburn RW, Iaci JF, Hackett C, Button DC, Caggiano AO, Parry TJ. AC105 Increases Extracellular Magnesium Delivery and Reduces Excitotoxic Glutamate Exposure within Injured Spinal Cords in Rats. J Neurotrauma 2016; 34:685-694. [PMID: 27503053 DOI: 10.1089/neu.2016.4607] [Citation(s) in RCA: 8] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Magnesium (Mg2+) homeostasis is impaired following spinal cord injury (SCI) and the loss of extracellular Mg2+ contributes to secondary injury by various mechanisms, including glutamate neurotoxicity. The neuroprotective effects of high dose Mg2+ supplementation have been reported in many animal models. Recent studies found that lower Mg2+ doses also improved neurologic outcomes when Mg2+ was formulated with polyethylene glycol (PEG), suggesting that a PEG/ Mg2+ formulation might increase Mg2+ delivery to the injured spinal cord, compared with that of MgSO4 alone. Here, we assessed spinal extracellular Mg2+ and glutamate levels following SCI in rats using microdialysis. Basal levels of extracellular Mg2+ (∼0.5 mM) were significantly reduced to 0.15 mM in the core and 0.12 mM in the rostral peri-lesion area after SCI. A single intravenous infusion of saline or of MgSO4 at 192 μmoL/kg did not significantly change extracellular Mg2+ concentrations. However, a single infusion of AC105 (a MgCl2 in PEG) at an equimolar Mg2+ dose significantly increased the Mg2+ concentration to 0.3 mM (core area) and 0.25 mM (rostral peri-lesion area). Moreover, multiple AC105 treatments completely restored the depleted extracellular Mg2+ concentrations after SCI to levels in the uninjured spinal cord. Repeated MgSO4 infusions slightly increased the Mg2+ concentrations while saline infusion had no effect. In addition, AC105 treatment significantly reduced extracellular glutamate levels in the lesion center after SCI. These results indicate that intravenous infusion of PEG-formulated Mg2+ normalized the Mg2+ homeostasis following SCI and reduced potentially neurotoxic glutamate levels, consistent with a neuroprotective mechanism of blocking excitotoxicity.
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Affiliation(s)
| | | | | | - Chia Ung
- Acorda Therapeutics, Inc. , Ardsley, New York
| | | | | | | | | | | | | | - Tom J Parry
- Acorda Therapeutics, Inc. , Ardsley, New York
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20
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Burnett AL, Sezen SF, Hoke A, Caggiano AO, Iaci J, Lagoda G, Musicki B, Bella AJ. GGF2 is neuroprotective in a rat model of cavernous nerve injury-induced erectile dysfunction. J Sex Med 2015; 12:897-905. [PMID: 25639458 DOI: 10.1111/jsm.12834] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Erectile dysfunction is a major complication of radical prostatectomy, commonly associated with penile neuropathy. In animal models of peripheral nerve injury, glial growth factor-2 (GGF2), a member of the neuregulin family of growth factors, has neuroprotective and neurorestorative properties, but this potential has not been established after cavernous nerve (CN) injury. AIMS The effectiveness of GGF2 in preserving axonal integrity and recovering erectile function in a rat model of radical prostatectomy-associated CN injury. METHODS Adult male Sprague-Dawley rats underwent bilateral CN crush injury (BCNI) or sham surgery. Rats were administered GGF2 (0.5, 5, or 15 mg/kg) or vehicle subcutaneously 24 hour pre and 24-hour post-BCNI, and once weekly for 5 weeks. Erectile function was assessed in response to electrical stimulation of the CN. CN survival was assessed by fluorogold retrograde axonal tracing in major pelvic ganglia (MPG). Unmyelinated axons in the CNs were quantitated by electron microscopy. MAIN OUTCOME MEASURES Erectile function recovery, CN survival, and unmyelinated CN axon preservation in response to GGF2 treatment following BCNI. RESULTS Erectile function was decreased (P < 0.05) after BCNI, and it was improved (P < 0.05) by all doses of GGF2. The number of fluorogold-labeled cells in the MPG was reduced (P < 0.05) by BCNI and was increased (P < 0.05) by GGF2 (0.5 and 5 mg/kg). The percentage of denervated Schwann cells in the BCNI group was higher (P < 0.05) than that in the sham-treated group and was decreased (P < 0.05) in the GGF2-treated (5 mg/kg) BCNI group. In the BCNI + GGF2 (5 mg/kg) group, the unmyelinated fiber histogram demonstrated a rightward shift, indicating an increased number of unmyelinated axons per Schwann cell compared with the BCNI group. CONCLUSIONS GGF2 promotes erectile function recovery following CN injury in conjunction with preserving unmyelinated CN fibers. Our findings suggest the clinical opportunity to develop GGF2 as a neuroprotective therapy for radical prostatectomy.
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Affiliation(s)
- Arthur L Burnett
- Department of Urology, The James Buchanan Brady Urological Institute, The Johns Hopkins School of Medicine, Baltimore, MD, USA
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21
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Galindo CL, Kasasbeh E, Murphy A, Ryzhov S, Lenihan S, Ahmad FA, Williams P, Nunnally A, Adcock J, Song Y, Harrell FE, Tran TL, Parry TJ, Iaci J, Ganguly A, Feoktistov I, Stephenson MK, Caggiano AO, Sawyer DB, Cleator JH. Anti-remodeling and anti-fibrotic effects of the neuregulin-1β glial growth factor 2 in a large animal model of heart failure. J Am Heart Assoc 2014; 3:e000773. [PMID: 25341890 PMCID: PMC4323814 DOI: 10.1161/jaha.113.000773] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Neuregulin-1β (NRG-1β) is a growth factor critical for cardiac development and repair with therapeutic potential for heart failure. We previously showed that the glial growth factor 2 (GGF2) isoform of NRG-1β improves cardiac function in rodents after myocardial infarction (MI), but its efficacy in a large animal model of cardiac injury has not been examined. We therefore sought to examine the effects of GGF2 on ventricular remodeling, cardiac function, and global transcription in post-MI swine, as well as potential mechanisms for anti-remodeling effects. METHODS AND RESULTS MI was induced in anesthetized swine (n=23) by intracoronary balloon occlusion. At 1 week post-MI, survivors (n=13) received GGF2 treatment (intravenous, biweekly for 4 weeks; n=8) or were untreated (n=5). At 5 weeks post-MI, fractional shortening was higher (32.8% versus 25.3%, P=0.019), and left ventricular (LV) end-diastolic dimension lower (4.5 versus 5.3 cm, P=0.003) in GGF2-treated animals. Treatment altered expression of 528 genes, as measured by microarrays, including collagens, basal lamina components, and matricellular proteins. GGF2-treated pigs exhibited improvements in LV cardiomyocyte mitochondria and intercalated disk structures and showed less fibrosis, altered matrix structure, and fewer myofibroblasts (myoFbs), based on trichrome staining, electron microscopy, and immunostaining. In vitro experiments with isolated murine and rat cardiac fibroblasts demonstrate that NRG-1β reduces myoFbs, and suppresses TGFβ-induced phospho-SMAD3 as well as αSMA expression. CONCLUSIONS These results suggest that GGF2/NRG-1β prevents adverse remodeling after injury in part via anti-fibrotic effects in the heart.
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Affiliation(s)
- Cristi L Galindo
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Ehab Kasasbeh
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Abigail Murphy
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Sergey Ryzhov
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Sean Lenihan
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Farhaan A Ahmad
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Philip Williams
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Amy Nunnally
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Jamie Adcock
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Yanna Song
- Department of Biostatistics, Vanderbilt University, Nashville, TN (Y.S., F.E.H.)
| | - Frank E Harrell
- Department of Biostatistics, Vanderbilt University, Nashville, TN (Y.S., F.E.H.)
| | - Truc-Linh Tran
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - Tom J Parry
- Acorda Therapeutics, Ardsley, NY (T.J.P., J.I., A.G., A.O.C.)
| | - Jen Iaci
- Acorda Therapeutics, Ardsley, NY (T.J.P., J.I., A.G., A.O.C.)
| | | | - Igor Feoktistov
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | | | | | - Douglas B Sawyer
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.L.G., E.K., A.M., S.R., S.L., F.A.A., P.W., A.N., J.A., T.L.T., I.F., D.B.S.)
| | - John H Cleator
- Department of Pharmacology, Vanderbilt University, Nashville, TN (J.H.C.)
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22
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Srinivas M, Cao J, Zilinski R, Caggiano AO, Button D. Abstract 226: GGF2 Requires Activation Of PI3 Kinase Pathway To Mediate Cytoprotective Effects In The Mouse Atrial-derived Hl-1 Cardiomyocyte-like Cell Line. Circ Res 2014. [DOI: 10.1161/res.115.suppl_1.226] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Glial growth factor (GGF2) is a Neuregulin-1 (NRG-1), which binds ErbB receptors and activates downstream cell signaling processes. NRG-1 ligands and their receptors are required for cardiac development and adult cardiac function. GGF2 has been shown to improve left ventricular function in several models of heart failure though the mechanisms by which GGF2 is efficacious are poorly understood. GGF2 is currently in clinical trials for treatment of congestive heart failure. Many studies have focused on GGF2 regulation of PI3 kinase (PI3K) as measured by formation of pAKT
in vivo
and in numerous cell lines, including HL-1 cells, neonatal rat ventricular myocytes (NRVMs) and human iPSC-derived cardiomyocytes. NRG-1s also activate the MAP kinase (MAPK) pathway as measured by pERK1/2 formation. To better understand GGF2 action in the stressed heart, we have developed
in vitro
systems to study GGF2 protection of cardiomyocytes from doxorubicin induced toxicity. After serum starvation, cells were pre-incubated with GGF2 (0.15 pM to 9.5 nM) for 1 hr followed by exposure to 1 μM doxorubicin for 18 hrs. After doxorubicin treatment MTT labeling index of cultures was used as an endpoint measurement of cell metabolic status. Doxorubicin decreases MTT labeling index by 90% while GGF2 prevented this toxicity by almost 50% compared to untreated cells, with an EC
50
of 83.3±19.4 pM . This effect appears to be dependent upon AKT signaling and not MAPK as assessed using inhibitors of both pathways. Inhibition of MAPK increases pAKT formation without changing extent of GGF2 protection. Blocking ErbB4 receptor, highly expressed in cardiomyocytes, causes a decrease in pAKT formation, suggesting that this receptor is important for mediating GGF2 action in these cells. Our results demonstrate that, in HL-1 cells, GGF2 mediates cytoprotective responses which require PI3K activation. Similar studies are being pursued in doxorubicin-treated NRVMs and human iPS derived cardiomyocytes. Initial results indicate GGF2 also mediates cytoprotective effects in these cell types. Future efforts will be aimed at elucidating potential roles for PI3K-dependent GGF2 regulation of mitochondrial function, Ca
2+
signaling or REDOX regulation in the observed cytoprotective actions.
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Affiliation(s)
| | - Jing Cao
- Acorda Therapeutics, Ardsley, NY
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Iaci JF, Parry TJ, Huang Z, Finklestein SP, Ren J, Barrile DK, Davenport MD, Wu R, Blight AR, Caggiano AO. Dalfampridine improves sensorimotor function in rats with chronic deficits after middle cerebral artery occlusion. Stroke 2013; 44:1942-50. [PMID: 23652269 DOI: 10.1161/strokeaha.111.000147] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND PURPOSE Stroke survivors often have permanent deficits that are only partially addressed by physical therapy. This study evaluated the effects of dalfampridine, a potassium channel blocker, on persistent sensorimotor deficits in rats with treatment initiated 4 or 8 weeks after stroke. METHODS Rats underwent permanent middle cerebral artery occlusion. Sensorimotor function was measured using limb-placing and body-swing symmetry tests, which normally show a partial recovery from initial deficits that plateaus ≈4 weeks after permanent middle cerebral artery occlusion. Dalfampridine was administered starting at 4 or 8 weeks after permanent middle cerebral artery occlusion in 2 blinded, vehicle-controlled studies. Plasma samples were collected and brain tissue was processed for histologic assessment. RESULTS Dalfampridine treatment (0.5-2.0 mg/kg) improved forelimb- and hindlimb-placing responses and body-swing symmetry in a reversible and dose-dependent manner. Plasma dalfampridine concentrations correlated with dose. Brain infarct volumes showed no differences between treatment groups. CONCLUSIONS Dalfampridine improves sensorimotor function in the rat permanent middle cerebral artery occlusion model. Dalfampridine extended-release tablets (prolonged release fampridine outside the United States) are used to improve walking in patients with multiple sclerosis, and these preclinical data provide a strong rationale for examining the potential of dalfampridine to treat chronic stable deficits in stroke patients. CLINICAL TRIAL REGISTRATION URL http://www.clinicaltrials.gov. Unique identifier: NCT01605825.
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Hill MF, Patel AV, Murphy A, Smith HM, Galindo CL, Pentassuglia L, Peng X, Lenneman CG, Odiete O, Friedman DB, Kronenberg MW, Zheng S, Zhao Z, Song Y, Harrell FE, Srinivas M, Ganguly A, Iaci J, Parry TJ, Caggiano AO, Sawyer DB. Intravenous glial growth factor 2 (GGF2) isoform of neuregulin-1β improves left ventricular function, gene and protein expression in rats after myocardial infarction. PLoS One 2013; 8:e55741. [PMID: 23437060 PMCID: PMC3578842 DOI: 10.1371/journal.pone.0055741] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Accepted: 12/29/2012] [Indexed: 11/19/2022] Open
Abstract
AIMS Recombinant Neuregulin (NRG)-1β has multiple beneficial effects on cardiac myocytes in culture, and has potential as a clinical therapy for heart failure (HF). A number of factors may influence the effect of NRG-1β on cardiac function via ErbB receptor coupling and expression. We examined the effect of the NRG-1β isoform, glial growth factor 2 (GGF2), in rats with myocardial infarction (MI) and determined the impact of high-fat diet as well as chronicity of disease on GGF2 induced improvement in left ventricular systolic function. Potential mechanisms for GGF2 effects on the remote myocardium were explored using microarray and proteomic analysis. METHODS AND RESULTS Rats with MI were randomized to receive vehicle, 0.625 mg/kg, or 3.25 mg/kg GGF2 in the presence and absence of high-fat feeding beginning at day 7 post-MI and continuing for 4 weeks. Residual left ventricular (LV) function was improved in both of the GGF2 treatment groups compared with the vehicle treated MI group at 4 weeks of treatment as assessed by echocardiography. High-fat diet did not prevent the effects of high dose GGF2. In experiments where treatment was delayed until 8 weeks after MI, high but not low dose GGF2 treatment was associated with improved systolic function. mRNA and protein expression analysis of remote left ventricular tissue revealed a number of changes in myocardial gene and protein expression altered by MI that were normalized by GGF2 treatment, many of which are involved in energy production. CONCLUSIONS This study demonstrates that in rats with MI induced systolic dysfunction, GGF2 treatment improves cardiac function. There are differences in sensitivity of the myocardium to GGF2 effects when administered early vs. late post-MI that may be important to consider in the development of GGF2 in humans.
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Affiliation(s)
- Michael F. Hill
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Amish V. Patel
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Abigail Murphy
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Holly M. Smith
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Cristi L. Galindo
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Laura Pentassuglia
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Xuyang Peng
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Carrie G. Lenneman
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Oghenerukevwe Odiete
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - David B. Friedman
- Department of Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Marvin W. Kronenberg
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Siyuen Zheng
- Biomedical Informatics and Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Zhongming Zhao
- Biomedical Informatics and Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Yanna Song
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Frank E. Harrell
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Maya Srinivas
- Acorda Therapeutics, Inc., Hawthorne, New York, United States of America
| | - Anindita Ganguly
- Acorda Therapeutics, Inc., Hawthorne, New York, United States of America
| | - Jennifer Iaci
- Acorda Therapeutics, Inc., Hawthorne, New York, United States of America
| | - Tom J. Parry
- Acorda Therapeutics, Inc., Hawthorne, New York, United States of America
| | | | - Douglas B. Sawyer
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- * E-mail:
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Galindo CL, Murphy A, Hill M, Cleator J, Kasasbeh E, Caggiano AO, Parry T, Sawyer DB. Abstract 234: Transcriptional Profiling of Neuregulin-Induced Myocardial Recovery After Infarction in Rats and Swine. Circ Res 2012. [DOI: 10.1161/res.111.suppl_1.a234] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Neuregulin-1 (NRG-1) mediates cell-cell interactions and is a critical growth and developmental signaling molecule in the heart. We have been examining whether the recombinant NRG-1 isoform known as glial growth factor 2 (GGF2) has therapeutic potential for heart failure. In rats and swine with experimental myocardial infarction we have found that GGF2 treatment improves myocardial function and limits progressive myocardial remodeling. To understand potential mechanisms for this effect, we compared gene expression in these animals using microarrays. In rats we compared Sham operated, MI treated with vehicle, and MI treated with GGF2 at a single dose. We found that GGF2 treatment was associated with correction of mitochondrial and metabolic genes altered by MI compared to Sham-operated rats. When compared to 9 published datasets of ∼400 samples from rodents and human heart failure, we identified 563 genes associated with heart failure that were also reversed in expression in response to GGF2. Ingenuity pathway analysis demonstrated clusters of genes associated with energy production and cardiovascular tissue development as particularly enriched in GGF2-treated versus untreated MI rats. In swine our analysis was confined to animals with MI +/- GGF2 treatment at two doses. There were 527 genes altered by GGF2 at both doses compared to untreated controls, with a clear GGF2 dose response. Transcripts altered in response to GGF2 treatment were mainly those associated with extracellular matrix structure and function, MAPK signaling, and p53-mediated apoptosis. Electron microscopy of remote infarct left ventricular tissue from swine confirmed extreme morphological differences in mitochondria from GGF2-treated and vehicle-treated control pigs. Most striking was recovery of intercalated discs in response to GGF2, compared to severe disruption of intercalated disc structures in vehicle-treated control animals.
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Bella AJ, Iaci JF, Coderre E, Renaud LP, Caggiano AO. 748 REMOTE FROM INJURY-SITE DELIVERY OF GLIAL GROWTH FACTOR 2 (GGF2) FACILITATES RECOVERY OF ERECTILE DYSFUNCTION FOLLOWING BILATERAL CAVERNOUS NERVE INJURY IN THE RAT WITH DIRECT EVIDENCE OF CAVERNOUS NERVE PRESERVATION. J Urol 2011. [DOI: 10.1016/j.juro.2011.02.1773] [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: 10/18/2022]
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27
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Sun M, Yan X, Bian Y, Caggiano AO, Morgan JP. Improving murine embryonic stem cell differentiation into cardiomyocytes with neuregulin-1: differential expression of microRNA. Am J Physiol Cell Physiol 2011; 301:C21-30. [PMID: 21451102 DOI: 10.1152/ajpcell.00141.2010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Identification of factors that direct embryonic stem (ES) cell (ESC) differentiation into functional cardiomyocytes is essential for successful use of ESC-based therapy for cardiac repair. Neuregulin-1 (NRG1) and microRNA play important roles in the cardiac differentiation of ESCs. Understanding how NRG1 regulates microRNA will provide new mechanistic insights into the role of NRG1 on ESCs. It may also lead to the discovery of novel microRNAs that are important for ESC cardiac differentiation. The objective of this study was to assess the microRNA expression profile during NRG1-induced ESC cardiac differentiation. Murine ESCs were incubated with a recombinant NRG1β or an inhibitor of ErbB2 or ErbB4 during hanging drop-induced cardiac differentiation. The expression of cardiac-specific markers and microRNAs was analyzed by RT-PCR and microRNA array, respectively. We found that the expression of NRG1 and the ErbB receptors was increased during hanging drop-induced cardiac differentiation of ESCs. NRG1 stimulation during a specific developmental window enhanced, while inhibition of the ErbB2 or ErbB4 receptor inhibited, cardiac differentiation of ESCs. NRG1 increased the expression of mmu-miR-296-3p and mmu-miR-200c*, and decreased mmu-miR-465b-5p. Inhibition of mmu-miR-296-3p or mmu-miR-200c* decreased, while inhibition of mmu-miR-465-5p increased, the differentiation of ESCs into the cardiac lineage. This is the first report demonstrating that microRNAs are differentially regulated by NRG1-ErbB signaling during cardiac differentiation of ESCs. This study has also identified new microRNAs that are important for ESC cardiac differentiation.
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Affiliation(s)
- Maoyun Sun
- Division of Cardiovascular Research, Department of Medicine, Caritas St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02135, USA
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28
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Iaci JF, Ganguly A, Finklestein SP, Parry TJ, Ren J, Saha S, Sietsma DK, Srinivas M, Vecchione AM, Caggiano AO. Glial growth factor 2 promotes functional recovery with treatment initiated up to 7 days after permanent focal ischemic stroke. Neuropharmacology 2010; 59:640-9. [PMID: 20691195 DOI: 10.1016/j.neuropharm.2010.07.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 07/07/2010] [Accepted: 07/22/2010] [Indexed: 12/15/2022]
Abstract
Neuregulins are a family of growth factors essential for normal cardiac and nervous system development. The EGF-like domain of neuregulins contains the active site which binds and activates signaling cascades through ErbB receptors. A neuregulin-1 gene EGF-like fragment demonstrated neuroprotection in the transient middle cerebral artery occlusion (MCAO) stroke model and drastically reduced infarct volume (Xu et al., 2004). Here we use a permanent MCAO rat model to initially compare two products of the neuregulin-1 gene and also assess levels of recovery with acute versus delayed time to treatment. In the initial study full-length glial growth factor 2 (GGF2) and an EGF-like domain fragment were compared with acute intravenous delivery. In a second study GGF2 only was delivered starting at 24h, 3 days or 7 days after permanent ischemia was induced. In both studies daily intravenous administration continued for 10 days. Recovery of neurological function was assessed using limb placing and body swing tests. GGF2 had similar functional improvements compared to the EGF-like domain fragment at equimolar doses, and a higher dose of GGF2 demonstrated more robust functional improvements compared to a lower dose. GGF2 improved sensorimotor recovery with all treatment paradigms, even enhancing recovery of function with a delay of 7 days to treatment. Histological assessments did not show any associated reduction in infarct volume at either 48 h or 21 days post-ischemic event. Neurorestorative effects of this kind are of great potential clinical importance, given the difficulty of delivering neuroprotective therapies within a short time after an ischemic event in human patients. If confirmed by additional work including additional data on mechanism(s) of improved outcome with verification in other stroke models, one can make a compelling case to bring GGF2 to clinical trials as a neurorestorative approach to improving outcome following stroke injury.
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Affiliation(s)
- Jennifer F Iaci
- Acorda Therapeutics Inc., 15 Skyline Drive, Hawthorne, NY 10532, USA.
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29
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Bian Y, Sun M, Silver M, Ho KKL, Marchionni MA, Caggiano AO, Stone JR, Amende I, Hampton TG, Morgan JP, Yan X. Neuregulin-1 attenuated doxorubicin-induced decrease in cardiac troponins. Am J Physiol Heart Circ Physiol 2009; 297:H1974-83. [PMID: 19801490 DOI: 10.1152/ajpheart.01010.2008] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neuregulin-1 (NRG1) is a potential therapeutic agent for the treatment of doxorubicin (Dox)-induced heart failure. NRG1, however, activates the erbB2 receptor, which is frequently overexpressed in breast cancers. It is, therefore, important to understand how NRG1, via erbB2, protects the heart against Dox cardiotoxicity. Here, we studied NRG1-erbB2 signaling in Dox-treated mice hearts and in isolated neonatal rat ventricular myocytes (NRVM). Male C57BL/6 mice were treated with recombinant NRG1 before and daily after a single dose of Dox. Cardiac function was determined by catheterization. Two-week survival was analyzed by the Kaplan-Meier method. Cardiac troponins [cardiac troponin I (cTnI) and cardiac troponin T (cTnT)] and phosphorylated Akt protein levels were determined in mice hearts and in NRVM by Western blot analysis. Activation of caspases and ubiquitinylation of troponins were determined in NRVM by caspase assay and immunoprecipitation. NRG1 significantly improved survival and cardiac function in Dox-treated mice. NRG1 reduced the decrease in cTnI, cTnT, and cardiac troponin C (cTnC) and maintained Akt phosphorylation in Dox-treated mice hearts. NRG1 reduced the decrease in cTnI and cTnT mRNA and proteins in Dox-treated NRVM. Inhibition of erbB2, phosphoinositide 3-kinase (PI3K), Akt, and mTOR blocked the protective effects of NRG1 on cTnI and cTnT in NRVM. NRG1 significantly reduced Dox-induced caspase activation, which degraded troponins, in NRVM. NRG1 reduced Dox-induced proteasome degradation of cTnI. NRG1 attenuates Dox-induced decrease in cardiac troponins by increasing transcription and translation and by inhibiting caspase activation and proteasome degradation of troponin proteins. NRG1 maintains cardiac troponins by the erbB2-PI3K pathway, which may lessen Dox-induced cardiac dysfunction.
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Affiliation(s)
- Yun Bian
- Cardiovascular Research, Caritas St. Elizabeth's Medical Center, 736 Cambridge St. CBR3, Boston, MA 02135, USA
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Iaci JF, Vecchione AM, Zimber MP, Caggiano AO. Chondroitin Sulfate Proteoglycans in Spinal Cord Contusion Injury and the Effects of Chondroitinase Treatment. J Neurotrauma 2007; 24:1743-59. [DOI: 10.1089/neu.2007.0366] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Curinga GM, Snow DM, Mashburn C, Kohler K, Thobaben R, Caggiano AO, Smith GM. Mammalian-produced chondroitinase AC mitigates axon inhibition by chondroitin sulfate proteoglycans. J Neurochem 2007; 102:275-88. [PMID: 17394547 DOI: 10.1111/j.1471-4159.2007.04530.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [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] [Indexed: 11/29/2022]
Abstract
Chondroitin sulfate proteoglycans (CSPGs) are up-regulated following spinal cord injury and are partly responsible for failed regeneration. Experimental paradigms in vivo that degrade chondroitin sulfate glycosaminoglycan chains with the bacterial enzyme, chondroitinase, greatly enhance the ability of axons to regenerate through the glial scar. Unfortunately, enthusiasm for this treatment paradigm is diminished by the lack of a minimally invasive and sustained delivery method. To address these deficits, we have engineered a Tet-On adenoviral vector encoding chondroitinase AC and have characterized its enzymatic function in vitro. U373 human astrocytoma cells were transduced with adenovirus and subsequently induced with doxycycline to secrete enzymatically active chondroitinase as detected by western blot and kinetic analyses. Enzymatic activity demonstrated biological relevance in studies where neurite outgrowth into and across CSPG-adsorbed regions pre-treated with conditioned media from chondroitinase secreting astrocytes was significantly increased compared with untreated controls (p < 0.0001). We also measured important parameters of enzyme activity including: pH, temperature, and enzyme stability that are fundamental to harnessing the true therapeutic potential of this approach. The use of resident cells for continuous secretion of CSPG-degrading enzymes at the site of the glial scar promises to be of greater clinical relevance than contemporary methods.
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Affiliation(s)
- Gabrielle M Curinga
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky 40536-0509, USA
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Caggiano AO, Zimber MP, Ganguly A, Blight AR, Gruskin EA. Chondroitinase ABCI improves locomotion and bladder function following contusion injury of the rat spinal cord. J Neurotrauma 2005; 22:226-39. [PMID: 15716629 DOI: 10.1089/neu.2005.22.226] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [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: 11/13/2022] Open
Abstract
Chondroitin sulfate proteoglycans are synthesized and deposited in the spinal cord following injury. These proteoglycans may restrict regeneration and plasticity and contribute to the limited recovery seen after an injury. Chondroitinase, a bacterial enzyme that catalyzes the hydrolysis of the chondroitin chains on proteoglycans, has been shown to improve motor and sensory function following partial transection lesions of the spinal cord. To assess the effects of chondroitinase in a clinically relevant model of spinal cord injury, 128 female Long-Evans rats received either a severe, moderate, or mild contusion injury at the vertebral level T9/T10 with a forceps model and were treated for 2 weeks with chondroitinase ABCI at 0.06 Units per dose, penicillinase, or vehicle control via an intrathecal catheter placed near the injury. Motor behavior was measured by open-field testing of locomotion and bladder function monitored by measuring daily residual urine volumes. Animals treated with chondroitinase showed significant improvements in open-field locomotor activity as measured by the Basso, Beattie and Bresnahan scoring system after both severe and moderate SCI (p<0.05 and 0.01, respectively). No significant locomotor differences were observed in the mild injury group. In the moderate injury group, residual urine volumes were reduced with chondroitinase treatment by 2 weeks after injury (p<0.05) and in the severe injury group, by 6 weeks after injury (NS). These results demonstrate that chondroitinase is effective at promoting both somatic and autonomic motor recovery following a clinically relevant contusion spinal cord injury and is a candidate as a therapeutic for human spinal cord injury.
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Fyfe JA, Beauchamp LM, Caggiano AO, Price RD, Yamaji T, Matsuoka N, Krenitsky TA. KP544 amplifies the effects of nerve growth factor on cell differentiation and is neuroprotective. Drug Dev Res 2004. [DOI: 10.1002/ddr.10385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Affiliation(s)
- J Schwab
- Department of Pediatrics, Univeristy of Chicago School of Medicine, IL 60637, USA
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Abstract
Prostaglandins (PGs) are potent modulators of brain function under normal and pathological conditions. The diverse effects of PGs are due to the various actions of specific receptor subtypes for these prostanoids. Recent work has shown that PGE2, while generally considered a proinflammatory molecule, reduces microglial activation and thus has an antiinflammatory effect on these cells. To gain further insight to the mechanisms by which PGE2 influences the activation of microglia, we investigated PGE receptor subtype, i.e., EP1, EP2, EP3, and EP4, expression and function in cultured rat microglia. RT-PCR showed the presence of the EP1 and EP2 but not EP3 and EP4 receptor subtypes. Sequencing confirmed their identity with previously published receptor subtypes. PGE2 and the EP1 agonist 17-phenyl trinor PGE2 but not the EP3 agonist sulprostone elicited reversible intracellular [Ca2+] increases in microglia as measured by fura-2. PGE2 and the EP2/EP4-specific agonists 11-deoxy-PGE1 and 19-hydroxy-PGE2 but not the EP4-selective agonist 1-hydroxy-PGE1 induced dose-dependent production of cyclic AMP (cAMP). Interleukin (IL)-1beta production, a marker of activated microglia, was also measured following lipopolysaccharide exposure in the presence or absence of the receptor subtype agonists. PGE2 and the EP2 agonists reduced IL-1beta production. IL-1beta production was unchanged by EP1, EP3, and EP4 agonists. The adenylyl cyclase activator forskolin and the cAMP analogue dibutyryl cAMP also reduced IL-1beta production. Thus, the inhibitory effects of PGE2 on microglia are mediated by the EP2 receptor subtype, and the signaling mechanism of this effect is likely via cAMP. These results show that the effects of PGE2 on microglia are receptor subtype-specific. Furthermore, they suggest that specific and selective manipulation of the effects of PGs on microglia and, as a result, brain function may be possible.
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Affiliation(s)
- A O Caggiano
- Committee on Neurobiology, University of Chicago, Illinois 60637, USA
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Caggiano AO, Kraig RP. Prostaglandin E2 and 4-aminopyridine prevent the lipopolysaccharide-induced outwardly rectifying potassium current and interleukin-1beta production in cultured rat microglia. J Neurochem 1998; 70:2357-68. [PMID: 9603200 PMCID: PMC2807138 DOI: 10.1046/j.1471-4159.1998.70062357.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [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] [Indexed: 12/31/2022]
Abstract
Brain inflammation includes microglial activation and enhanced production of diffusible chemical mediators, including prostaglandin E2. Prostaglandin E2 is generally considered a proinflammatory molecule, but it also promotes neuronal survival and down-regulates some aspects of microglial activation. It remains unknown, however, if and how prostaglandin E2 prevents microglial activation. In primary culture, microglial activation is predicted by a characteristic pattern of whole-cell potassium currents and interleukin-1beta production. We investigated if prostaglandin E2 could alter these currents and, if so, whether these currents are necessary for microglial activation. Microglia were isolated from mixed cell cultures prepared from neonatal rat brains and exposed to 0-10 microM prostaglandin E2 and lipopolysaccharide for 24 h. Currents were elicited by using standard patch-clamp technique, and interleukin-1beta production was measured by ELISA. Peak outward current densities in microglia treated with lipopolysaccharide plus prostaglandin E2 (10 nM) were reduced significantly from those of cells treated with lipopolysaccharide alone. Prostaglandin E2 and 4-aminopyridine (a blocker of outward potassium currents) also significantly reduced interleukin-1beta production. Thus, although prostaglandin E2 is classified generally as a proinflammatory chemical, it has complex roles in brain inflammation that include preventing microglial activation, perhaps by reducing the outward potassium current.
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Affiliation(s)
- A O Caggiano
- Committee on Neurobiology, University of Chicago, Illinois 60637, USA
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Abstract
Spreading depression (SD) confers either increased susceptibility to ischemic injury or a delayed protection. Because nitric oxide modulates ischemic injury, we investigated if altered expression of nitric oxide synthase (NOS) by SD could account for the effect of SD on ischemia. Furthermore, the identity of cells expressing NOS after SD is important, since SD results in heterogeneous, cell type-specific changes in intracellular environment, which can control NOS activity. Immunohistochemical, computer-based image analyses and Western blotting show that the number of neuronal NOS (nNOS)-positive cells in the somatosensory cortex was significantly increased at 6 hours and 3 days after SD (P < 0.05 and 0.01, respectively), whereas inducible NOS expression remained unchanged. Double-labeling of nNOS and glial fibrillary acidic protein identified these nNOS-positive cells as astrocytes. The effect of altered NO production on induced nNOS expression was examined by treating rats with sodium nitroprusside or NA-nitro-L-arginine methyl ester (LNAM) during SD. Increased nNOS expression was prevented by sodium nitroprusside and phenylephrine or phenylephrine alone, but not LNAM. Because SD increased astrocytic nNOS expression at time points correlating with both ischemic hypersensitivity and ischemic tolerance, the ability of SD to modulate ischemic injury must be complex, perhaps involving NOS but other factors as well.
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Affiliation(s)
- A O Caggiano
- Department of Neurology, University of Chicago, IL 60637, USA
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Abstract
Eicosanoids, produced from arachidonic acid by cyclooxygenases (COXs) and lipoxygenases (LIPOXs), are involved in numerous brain processes. To explore if brief and noninjurious stimuli chronically alter expression of these enzymes, we examined the induction of COX-2 and LIPOX expression following unilateral neocortical spreading depression (SD). Expression was examined over time and in regions not experiencing SD (hippocampus) but synaptically connected to the site of stimulation (cortex). One hundred six male Wistar rats had SD induced via microinjection of 0.5 M KCl (0.5 M NaCl for sham) into left parietal cortex every 9 minutes for 1 or 3 hours. One hour before SD some animals received dexamethasone (Dex), mepacrine (Mep), indomethacin (Indo), nordihydroguaiaretic acid (Ndga), phenylephrine (Pe), sodium nitroprusside (Snp) with Pe, or N omega-nitro-L-arginine methyl ester (Lnam). Animals survived for 0, 3, or 6 hours, or 1, 2, 3, 7, 14, 21, or 28 days. Brains were processed immunohistochemically for COX-2 and LIPOX, and the optical density (OD) of the left and right cortex, dentate gyrus (DG), CA3, and CA1 immunoreactivity (IR) were measured. Induction was expressed as the log of left divided by right side OD for each region. COX-2 IR in the left cortex was elevated rapidly and was sustained for 21 days following SD. COX-2 IR was also elevated in the ipsilateral hippocampus not experiencing SD, with the rank order of induction as follows: DG > CA3 > CA1. Dex, Snp, and/or Pe significantly reduced the induction of COX-2. No changes in LIPOX IR were observed. These results show that long-term changes in COX-2 expression are induced by SD and these changes decrease with synaptic distance. Benign stimuli increase COX-2 expression and thus may influence brain function for extended periods and at distant locations.
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Affiliation(s)
- A O Caggiano
- Committee on Neurobiology, University of Chicago, Illinois 60637, USA
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39
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Abstract
Microglia and astrocytes are transformed into reactive glia (RG) by brain disease and normal function. Eicosanoids and nitric oxide (NO), two intercellular mediators, may influence gliosis. We investigated how drugs that alter production of these paracrine signals effect induction of glial reactivity from spreading depression. Unilateral (left) neocortical spreading depression was induced in 95 halothane anesthetized rats by intracortical injections of 0.5 M KCl, with or without drug treatment (five animals/group). Immunohistochemical staining (IS) intensity using the OX-42 and anti-glial fibrillary acidic protein (GFAP) antibodies determined reactivity in microglia and astrocytes, respectively. After 3 days, brains were processed for OX-42 and GFAP-IS and mean optical densities (OD) of IS were measured. Average OD's (for OX-42) and the log ratio (left/right) of OD's (OX-42 and GFAP) were compared to normal animals. Spreading depression induced significant log ratios for both OX-42- and GFAP-IS (P's < 0.01). However, dexamethasone (a glucocorticoid), nordihydroguaiaretic acid (a lipoxygenase inhibitor), and nitroprusside (a NO donor) prevented significant left sided and log ratio OD values for microglia (P's > 0.05). L-Name, a NO synthase inhibitor, caused significant increases in left and right OD's for microglia (P's < 0.05). Mepacrine, a phospholipase A2 inhibitor, Indomethacin, a cyclooxygenase inhibitor, and phenylephrine, an adrenergic agonist, did not prevent induction of significant OX-42 log ratios (P's < 0.01, 0.05, 0.01), and resulted in increases in left side OD's (P's < 0.01, 0.05, 0.05). Significant GFAP log ratios occurred after spreading depression in all drug groups, P's < 0.01. Thus, induction of reactivity in microglia is more sensitive to eicosanoids and NO than in astrocytes.
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Affiliation(s)
- A O Caggiano
- Department of Neurology, University of Chicago, IL 60637
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40
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Abstract
The developmental appearance of microglia in the rat olfactory bulb was investigated through the use of selective staining with the B4-isolectin from Griffonia simplicifolia. No changes in the density or distribution of either the spherical, macrophage "ameboid" form or the highly arborized "ramified" variety of microglia were observed in the superficial layers of the bulb between postnatal days 10 and 30. The subependymal zone exhibited the only substantial population of ameboid cells and the only developmental increases in ramified cell density during this time-period. External single naris closure, which enhances cell death in the ipsilateral bulb, did not affect microglia density, presumably due to the unusually high numbers of microglia normally present in the bulb. The olfactory bulb has a dense and relatively uniform population of microglial cells from very early stages of postnatal life, perhaps because of the constant turnover of cells and processes.
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Affiliation(s)
- A O Caggiano
- Department of Psychology, University of Virginia, Charlottesville 22903
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41
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Brunjes PC, Caggiano AO, Korol DL, Stewart JS. Unilateral olfactory deprivation: effects on succinate dehydrogenase histochemistry and [3H]leucine incorporation in the olfactory mucosa. Brain Res Dev Brain Res 1991; 62:239-44. [PMID: 1722740 DOI: 10.1016/0165-3806(91)90171-e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Surgically closing one external naris reduces airflow through one half of the nasal cavity, decreasing the access of odors to the receptor sheet. In rats, unilateral naris occlusion performed near birth results in large reductions in the size of the olfactory bulb, the primary central relay, when examined 30 days later. Previous research has demonstrated that there is a rapid reduction in [3H]2-deoxyglucose (2-DG) and [3H]leucine uptake in the bulb within hours after naris closure. The present study examined whether similar rapid changes could be observed in the sensory periphery. Pups occluded on P1 and examined on P3 with succinate dehydrogenase histochemistry exhibited reduced staining on the closed side of the nasal cavity, suggesting occlusion results in reductions in mucosal metabolism. Larger differences in staining were observed in pups examined at P6. [3H]Leucine incorporation was quite similar on both sides of the nasal septum as late as 30 days post occlusion, suggesting less dramatic changes in protein synthesis. The results suggest that naris closure does indeed have rapid effects on mucosal function, but indicate that the changes are different than those observed in the bulb.
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Affiliation(s)
- P C Brunjes
- Department of Psychology, University of Virginia, Charlottesville 22903
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