1
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Joers V, Murray BC, McLaughlin C, Oliver D, Staley HE, Coronado J, Achat-Mendes C, Golshani S, Kelly SD, Goodson M, Lee D, Manfredsson FP, Moore Ii BM, Tansey MG. Modulation of cannabinoid receptor 2 alters neuroinflammation and reduces formation of alpha-synuclein aggregates in a rat model of nigral synucleinopathy. J Neuroinflammation 2024; 21:240. [PMID: 39334169 PMCID: PMC11438102 DOI: 10.1186/s12974-024-03221-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 09/02/2024] [Indexed: 09/30/2024] Open
Abstract
Research into the disequilibrium of microglial phenotypes has become an area of intense focus in neurodegenerative disease as a potential mechanism that contributes to chronic neuroinflammation and neuronal loss in Parkinson's disease (PD). There is growing evidence that neuroinflammation accompanies and may promote progression of alpha-synuclein (Asyn)-induced nigral dopaminergic (DA) degeneration. From a therapeutic perspective, development of immunomodulatory strategies that dampen overproduction of pro-inflammatory cytokines from chronically activated immune cells and induce a pro-phagocytic phenotype is expected to promote Asyn removal and protect vulnerable neurons. Cannabinoid receptor-2 (CB2) is highly expressed on activated microglia and peripheral immune cells, is upregulated in the substantia nigra of individuals with PD and in mouse models of nigral degeneration. Furthermore, modulation of CB2 protects against rotenone-induced nigral degeneration; however, CB2 has not been pharmacologically and selectively targeted in an Asyn model of PD. Here, we report that 7 weeks of peripheral administration of CB2 inverse agonist SMM-189 reduced phosphorylated (pSer129) Asyn in the substantia nigra compared to vehicle treatment. Additionally, SMM-189 delayed Asyn-induced immune cell infiltration into the brain as determined by flow cytometry, increased CD68 protein expression, and elevated wound-healing-immune-mediator gene expression. Additionally, peripheral immune cells increased wound-healing non-classical monocytes and decreased pro-inflammatory classical monocytes. In vitro analysis of RAW264.7 macrophages treated with lipopolysaccharide (LPS) and SMM-189 revealed increased phagocytosis as measured by the uptake of fluorescence of pHrodo E. coli bioparticles. Together, results suggest that targeting CB2 with SMM-189 skews immune cell function toward a phagocytic phenotype and reduces toxic aggregated species of Asyn. Our novel findings demonstrate that CB2 may be a target to modulate inflammatory and immune responses in proteinopathies.
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Affiliation(s)
- Valerie Joers
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA.
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, FL, USA.
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
| | | | | | - Danielle Oliver
- Department of Physiology, Emory University, Atlanta, GA, USA
| | - Hannah E Staley
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Jazmyn Coronado
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | | | - Sanam Golshani
- Department of Physiology, Emory University, Atlanta, GA, USA
| | - Sean D Kelly
- Department of Physiology, Emory University, Atlanta, GA, USA
| | - Matthew Goodson
- Department of Physiology, Emory University, Atlanta, GA, USA
| | - Danica Lee
- Department of Physiology, Emory University, Atlanta, GA, USA
| | - Fredric P Manfredsson
- Parkinson's Disease Research Unit, Department of Translational Neuroscience, Barrow Neurological Institute, Phoenix, AZ, USA
| | - Bob M Moore Ii
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Malú Gámez Tansey
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
- Norman Fixel Institute for Neurological Diseases, University of Florida Health, Gainesville, FL, USA
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2
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Mondal K, Del Mar NA, Gary AA, Grambergs RC, Yousuf M, Tahia F, Stephenson B, Stephenson DJ, Chalfant CE, Reiner A, Mandal N. Sphingolipid changes in mouse brain and plasma after mild traumatic brain injury at the acute phases. Lipids Health Dis 2024; 23:200. [PMID: 38937745 PMCID: PMC11209960 DOI: 10.1186/s12944-024-02186-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 06/14/2024] [Indexed: 06/29/2024] Open
Abstract
BACKGROUND Traumatic brain injury (TBI) causes neuroinflammation and can lead to long-term neurological dysfunction, even in cases of mild TBI (mTBI). Despite the substantial burden of this disease, the management of TBI is precluded by an incomplete understanding of its cellular mechanisms. Sphingolipids (SPL) and their metabolites have emerged as key orchestrators of biological processes related to tissue injury, neuroinflammation, and inflammation resolution. No study so far has investigated comprehensive sphingolipid profile changes immediately following TBI in animal models or human cases. In this study, sphingolipid metabolite composition was examined during the acute phases in brain tissue and plasma of mice following mTBI. METHODS Wildtype mice were exposed to air-blast-mediated mTBI, with blast exposure set at 50-psi on the left cranium and 0-psi designated as Sham. Sphingolipid profile was analyzed in brain tissue and plasma during the acute phases of 1, 3, and 7 days post-TBI via liquid-chromatography-mass spectrometry. Simultaneously, gene expression of sphingolipid metabolic markers within brain tissue was analyzed using quantitative reverse transcription-polymerase chain reaction. Significance (P-values) was determined by non-parametric t-test (Mann-Whitney test) and by Tukey's correction for multiple comparisons. RESULTS In post-TBI brain tissue, there was a significant elevation of 1) acid sphingomyelinase (aSMase) at 1- and 3-days, 2) neutral sphingomyelinase (nSMase) at 7-days, 3) ceramide-1-phosphate levels at 1 day, and 4) monohexosylceramide (MHC) and sphingosine at 7-days. Among individual species, the study found an increase in C18:0 and a decrease in C24:1 ceramides (Cer) at 1 day; an increase in C20:0 MHC at 3 days; decrease in MHC C18:0 and increase in MHC C24:1, sphingomyelins (SM) C18:0, and C24:0 at 7 days. Moreover, many sphingolipid metabolic genes were elevated at 1 day, followed by a reduction at 3 days and an absence at 7-days post-TBI. In post-TBI plasma, there was 1) a significant reduction in Cer and MHC C22:0, and an increase in MHC C16:0 at 1 day; 2) a very significant increase in long-chain Cer C24:1 accompanied by significant decreases in Cer C24:0 and C22:0 in MHC and SM at 3 days; and 3) a significant increase of C22:0 in all classes of SPL (Cer, MHC and SM) as well as a decrease in Cer C24:1, MHC C24:1 and MHC C24:0 at 7 days. CONCLUSIONS Alterations in sphingolipid metabolite composition, particularly sphingomyelinases and short-chain ceramides, may contribute to the induction and regulation of neuroinflammatory events in the early stages of TBI, suggesting potential targets for novel diagnostic, prognostic, and therapeutic strategies in the future.
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Affiliation(s)
- Koushik Mondal
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
- Molecular Diagnostics Laboratory, Department of Basic & Translational Research, Saroj Gupta Cancer Centre & Research Institute, Kolkata, WB, 700 063, India
| | - Nobel A Del Mar
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
| | - Ashlyn A Gary
- Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Richard C Grambergs
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
| | - Mohd Yousuf
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
| | - Faiza Tahia
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
| | - Benjamin Stephenson
- Departments of Medicine and Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, 22903, USA
| | - Daniel J Stephenson
- Departments of Medicine and Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, 22903, USA
| | - Charles E Chalfant
- Departments of Medicine and Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, 22903, USA
- Research Service, Richmond VA Medical Center, Richmond, VA, 23298, USA
| | - Anton Reiner
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA
| | - Nawajes Mandal
- Department of Ophthalmology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA.
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA.
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Centre, Memphis, TN, 38163, USA.
- Memphis VA Medical Center, Memphis, TN, 38104, USA.
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Kosar M, Sarott RC, Sykes DA, Viray AEG, Vitale RM, Tomašević N, Li X, Ganzoni RLZ, Kicin B, Reichert L, Patej KJ, Gómez-Bouzó U, Guba W, McCormick PJ, Hua T, Gruber CW, Veprintsev DB, Frank JA, Grether U, Carreira EM. Flipping the GPCR Switch: Structure-Based Development of Selective Cannabinoid Receptor 2 Inverse Agonists. ACS CENTRAL SCIENCE 2024; 10:956-968. [PMID: 38799662 PMCID: PMC11117691 DOI: 10.1021/acscentsci.3c01461] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/20/2024] [Accepted: 02/20/2024] [Indexed: 05/29/2024]
Abstract
We report a blueprint for the rational design of G protein coupled receptor (GPCR) ligands with a tailored functional response. The present study discloses the structure-based design of cannabinoid receptor type 2 (CB2R) selective inverse agonists (S)-1 and (R)-1, which were derived from privileged agonist HU-308 by introduction of a phenyl group at the gem-dimethylheptyl side chain. Epimer (R)-1 exhibits high affinity for CB2R with Kd = 39.1 nM and serves as a platform for the synthesis of a wide variety of probes. Notably, for the first time these fluorescent probes retain their inverse agonist functionality, high affinity, and selectivity for CB2R independent of linker and fluorophore substitution. Ligands (S)-1, (R)-1, and their derivatives act as inverse agonists in CB2R-mediated cAMP as well as G protein recruitment assays and do not trigger β-arrestin-receptor association. Furthermore, no receptor activation was detected in live cell ERK1/2 phosphorylation and Ca2+-release assays. Confocal fluorescence imaging experiments with (R)-7 (Alexa488) and (R)-9 (Alexa647) probes employing BV-2 microglial cells visualized CB2R expressed at endogenous levels. Finally, molecular dynamics simulations corroborate the initial docking data in which inverse agonists restrict movement of toggle switch Trp2586.48 and thereby stabilize CB2R in its inactive state.
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Affiliation(s)
- Miroslav Kosar
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Roman C. Sarott
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - David A. Sykes
- Faculty
of Medicine & Health Sciences, University
of Nottingham, Nottingham NG7 2UH, U.K.
- Centre
of Membrane Proteins and Receptors (COMPARE), University of Birmingham
and University of Nottingham, https://www.birmingham-nottingham.ac.uk/compare
| | - Alexander E. G. Viray
- Department
of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon 97239-3098, United States
| | - Rosa Maria Vitale
- Institute
of Biomolecular Chemistry, National Research
Council, Via Campi Flegrei
34, 80078 Pozzuoli, Italy
| | - Nataša Tomašević
- Center for
Physiology and Pharmacology, Medical University
of Vienna, Schwarzspanierstrasse
17, 1090 Vienna, Austria
| | - Xiaoting Li
- iHuman
Institute, ShanghaiTech University, Shanghai 201210, China
| | - Rudolf L. Z. Ganzoni
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Bilal Kicin
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Lisa Reichert
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Kacper J. Patej
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Uxía Gómez-Bouzó
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Wolfgang Guba
- Roche
Pharma Research & Early Development, Roche Innovation Center Basel,
F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland
| | - Peter J. McCormick
- Department
of Pharmacology and Therapeutics, University
of Liverpool, Ashton
Street, Liverpool L69 3GE, U.K.
| | - Tian Hua
- iHuman
Institute, ShanghaiTech University, Shanghai 201210, China
| | - Christian W. Gruber
- Center for
Physiology and Pharmacology, Medical University
of Vienna, Schwarzspanierstrasse
17, 1090 Vienna, Austria
| | - Dmitry B. Veprintsev
- Faculty
of Medicine & Health Sciences, University
of Nottingham, Nottingham NG7 2UH, U.K.
- Centre
of Membrane Proteins and Receptors (COMPARE), University of Birmingham
and University of Nottingham, https://www.birmingham-nottingham.ac.uk/compare
| | - James A. Frank
- Department
of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon 97239-3098, United States
- Vollum
Institute, Oregon Health & Science University, Portland, Oregon 97239-3098, United States
| | - Uwe Grether
- Roche
Pharma Research & Early Development, Roche Innovation Center Basel,
F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland
| | - Erick M. Carreira
- Laboratorium
für Organische Chemie, Eidgenössische
Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
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4
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Joers V, Murray BC, McLaughlin C, Oliver D, Staley H, Coronado J, Achat-Mendes C, Golshani S, Kelly SD, Goodson M, Lee D, Manfredsson FP, Moore BM, Tansey MG. Modulation of cannabinoid receptor 2 alters neuroinflammation and reduces formation of alpha-synuclein aggregates in a rat model of nigral synucleinopathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.25.554814. [PMID: 38562842 PMCID: PMC10983852 DOI: 10.1101/2023.08.25.554814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Research into the disequilibrium of microglial phenotypes has become an area of intense focus in neurodegenerative disease as a potential mechanism that contributes to chronic neuroinflammation and neuronal loss in Parkinson's disease (PD). There is growing evidence that neuroinflammation accompanies and may promote progression of alpha-synuclein (Asyn)-induced nigral dopaminergic (DA) degeneration. From a therapeutic perspective, development of immunomodulatory strategies that dampen overproduction of pro-inflammatory cytokines from chronically activated immune cells and induce a pro-phagocytic phenotype is expected to promote Asyn removal and protect vulnerable neurons. Cannabinoid receptor-2 (CB2) is highly expressed on activated microglia and peripheral immune cells, is upregulated in the substantia nigra of individuals with PD and in mouse models of nigral degeneration. Furthermore, modulation of CB2 protects against rotenone-induced nigral degeneration; however, CB2 has not been pharmacologically and selectively targeted in an Asyn model of PD. Here, we report that 7 weeks of peripheral administration of CB2 inverse agonist SMM-189 reduced phosphorylated (pSer129) alpha-synuclein in the substantia nigra compared to vehicle treatment. Additionally, SMM-189 delayed Asyn-induced immune cell infiltration into the brain as determined by flow cytometry, increased CD68 protein expression, and elevated wound-healing-immune-mediator gene expression. Additionally, peripheral immune cells increased wound-healing non-classical monocytes and decreased pro-inflammatory classical monocytes. In vitro analysis of RAW264.7 macrophages treated with lipopolysaccharide (LPS) and SMM-189 revealed increased phagocytosis as measured by the uptake of fluorescence of pHrodo E. coli bioparticles. Together, results suggest that targeting CB2 with SMM-189 skews immune cell function toward a phagocytic phenotype and reduces toxic aggregated species of Asyn. Our novel findings demonstrate that CB2 may be a target to modulate inflammatory and immune responses in proteinopathies.
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Affiliation(s)
- Valerie Joers
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | | | | | - Danielle Oliver
- Department of Physiology, Emory University, Atlanta, Georgia
| | - Hannah Staley
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Jazmyn Coronado
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | | | - Sanam Golshani
- Department of Physiology, Emory University, Atlanta, Georgia
| | - Sean D Kelly
- Department of Physiology, Emory University, Atlanta, Georgia
| | - Matthew Goodson
- Department of Physiology, Emory University, Atlanta, Georgia
| | - Danica Lee
- Department of Physiology, Emory University, Atlanta, Georgia
| | - Fredric P Manfredsson
- Parkinson's Disease Research Unit, Department of Translational Neuroscience, Barrow Neurological Institute, Phoenix, Arizona
| | - Bob M Moore
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Malú Gámez Tansey
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida
- Center for Translational Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
- Norman Fixel Institute for Neurological Diseases, University of Florida Health, Gainesville, Florida
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5
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Harper MM, Boehme NA, Dutca L, Navarro V. Increasing the number and intensity of shock tube generated blast waves leads to earlier retinal ganglion cell dysfunction and regional cell death. Exp Eye Res 2024; 239:109754. [PMID: 38113955 DOI: 10.1016/j.exer.2023.109754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 07/28/2023] [Accepted: 12/12/2023] [Indexed: 12/21/2023]
Abstract
The purpose of this study was to examine the effect of a blast exposure generated from a shock tube on retinal ganglion cell (RGC) function and structure. Mice were exposed to one of three blast conditions using a shock tube; a single blast wave of 20 PSI, a single blast wave of 30 PSI, or three blast waves of 30 PSI given on three consecutive days with a one-day inter-blast interval. The structure and function of the retina were analyzed using the pattern electroretinogram (PERG), the optomotor reflex (OMR), and optical coherence tomography (OCT). The in vivo parameters were examined at baseline, and then again 1-week, 4-weeks, and 16-weeks following blast exposure. The number of surviving RGCs was quantified at the end of the study. Analysis of mice receiving a 20 PSI injury showed decreased PERG and OMR responses 16-weeks post blast, without evidence of changed retinal thickness or RGC death. Mice subjected to a 30 PSI injury showed decreased PERG responses 4 weeks and 16 weeks after injury, without changes in the retinal thickness or RGC density. Mice subjected to 30 PSI X 3 blast exposures had PERG deficits 1-week and 4-weeks post exposure. There was also significant change in retinal thickness 1-week and 16-weeks post blast exposure. Mice receiving 30 PSI X 3 blast injuries had regional loss of RGCs in the central retina, but not in the mid-peripheral or peripheral retina. Overall, this study has shown that increasing the number of blast exposures and the intensity leads to earlier functional loss of RGCs. We have also shown regional RGC loss only when using the highest blast intensity and number of blast injuries.
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Affiliation(s)
- Matthew M Harper
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, IA, USA; Department of Biology, The University of Iowa, Iowa City, IA, USA; Veterans Administration Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, IA, USA.
| | - Nickolas A Boehme
- Veterans Administration Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, IA, USA
| | - Laura Dutca
- Veterans Administration Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, IA, USA
| | - Victor Navarro
- Veterans Administration Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, IA, USA
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6
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Hetzer SM, O'Connell C, Lallo V, Robson M, Evanson NK. Model matters: Differential outcomes in traumatic optic neuropathy pathophysiology between blunt and blast-wave mediated head injuries. Exp Neurol 2024; 372:114613. [PMID: 37995952 PMCID: PMC10870099 DOI: 10.1016/j.expneurol.2023.114613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 11/07/2023] [Accepted: 11/15/2023] [Indexed: 11/25/2023]
Abstract
Over 3 million people in the United States live with long-term disability because of a traumatic brain injury (TBI). The purpose of this study was to characterize and compare two different animal models of TBI (blunt head trauma and blast TBI) to determine common and divergent characteristics of these models. With recent literature reviews noting the prevalence of visual system injury in animal models of TBI, coupled with clinical estimates of 50-75% of all TBI cases, we decided to assess commonalities, if they existed, through visual system injury. A unilateral (left directed) blast and repeat blast model injury with coup-contra-coup injury patterns were compared to a midline blunt injury. Injuries were induced in adult male mice to observe and quantify visual deficits. Retinal ganglion cell loss and axonal degeneration in the optic tract, superior colliculus, and lateral geniculate nuclei were examined to trace injury outcomes throughout major vision-associated areas. Optokinetic response, immunohistochemistry, and western blots were analyzed. Where a single blunt injury produces significant visual deficits a single blast injury appears to have less severe visual consequences. Visual deficits after repeat blasts are similar to a single blast. Single blast injury induces contralateral damage to the right optic chiasm and tract whereas bilateral injury follows a single blunt TBI. Repeat blast injuries are required to see degeneration patterns in downstream regions similar to the damage seen in a single blunt injury. This finding is further supported by amyloid precursor protein (APP) staining in injured cohorts. Blunt injured groups present with staining 1.2 mm ahead of the optic nerve, indicating axonal breakage closer to the optic chiasm. In blast groups, APP was identifiable in a bilateral pattern only in the geniculate nucleus. Evidence for unilateral neuronal degeneration in brain tissue with bilateral axonal ruptures are pivotal discoveries in this model differentiation. Analysis of the two injury models suggests that there is a significant difference in the histological outcomes dependent on injury type, though visual system injury is likely present in more cases than are currently diagnosed clinically.
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Affiliation(s)
- S M Hetzer
- Neuroscience Graduate Program, University of Cincinnati College of Medicine, United States of America.
| | - C O'Connell
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of Cincinnati, United States of America
| | - V Lallo
- College of Arts and Sciences, University of Cincinnati, United States of America
| | - M Robson
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of Cincinnati, United States of America
| | - N K Evanson
- Department of Pediatrics, University of Cincinnati College of Medicine, United States of America; Division of Pediatric Rehabilitation Medicine, Cincinnati Children's Hospital Medical Center, United States of America
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7
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Ding L, Patel A, Shankar S, Driscoll N, Zhou C, Rex TS, Vitale F, Gallagher MJ. An Open-Source Mouse Chronic EEG Array System with High-Density MXene-Based Skull Surface Electrodes. eNeuro 2024; 11:ENEURO.0512-22.2023. [PMID: 38388423 PMCID: PMC10884564 DOI: 10.1523/eneuro.0512-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 11/12/2023] [Accepted: 12/18/2023] [Indexed: 02/24/2024] Open
Abstract
Electroencephalography (EEG) is an indispensable tool in epilepsy, sleep, and behavioral research. In rodents, EEG recordings are typically performed with metal electrodes that traverse the skull into the epidural space. In addition to requiring major surgery, intracranial EEG is difficult to perform for more than a few electrodes, is time-intensive, and confounds experiments studying traumatic brain injury. Here, we describe an open-source cost-effective refinement of this technique for chronic mouse EEG recording. Our alternative two-channel (EEG2) and sixteen-channel high-density EEG (HdEEG) arrays use electrodes made of the novel, flexible 2D nanomaterial titanium carbide (Ti3C2T x ) MXene. The MXene electrodes are placed on the surface of the intact skull and establish an electrical connection without conductive gel or paste. Fabrication and implantation times of MXene EEG electrodes are significantly shorter than the standard approach, and recorded resting baseline and epileptiform EEG waveforms are similar to those obtained with traditional epidural electrodes. Applying HdEEG to a mild traumatic brain injury (mTBI) model in mice of both sexes revealed that mTBI significantly increased spike-wave discharge (SWD) preictal network connectivity with frequencies of interest in the β-spectral band (12-30 Hz). These findings indicate that the fabrication of MXene electrode arrays is a cost-effective, efficient technology for multichannel EEG recording in mice that obviates the need for skull-penetrating surgery. Moreover, increased preictal β-frequency network connectivity may contribute to the development of early post-mTBI SWDs.
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Affiliation(s)
- Li Ding
- Department of Neurology, Vanderbilt University School of Medicine, Nashville 37232, Tennessee
| | - Aashvi Patel
- Department of Neurology, Vanderbilt University School of Medicine, Nashville 37232, Tennessee
| | - Sneha Shankar
- Departments of Bioengineering and Neurology, Center for Neuroengineering & Therapeutics, University of Pennsylvania, Philadelphia 19104, Pennsylvania
| | - Nicolette Driscoll
- Departments of Bioengineering and Neurology, Center for Neuroengineering & Therapeutics, University of Pennsylvania, Philadelphia 19104, Pennsylvania
| | - Chengwen Zhou
- Department of Neurology, Vanderbilt University School of Medicine, Nashville 37232, Tennessee
| | - Tonia S Rex
- Department of Ophthalmology & Visual Sciences, Vanderbilt University School of Medicine, Nashville 37232, Tennessee
| | - Flavia Vitale
- Departments of Bioengineering and Neurology, Center for Neuroengineering & Therapeutics, University of Pennsylvania, Philadelphia 19104, Pennsylvania
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia 19104, Pennsylvania
| | - Martin J Gallagher
- Department of Neurology, Vanderbilt University School of Medicine, Nashville 37232, Tennessee
- Department of Veteran's Affairs, Tennessee Valley Health System, Nashville 37212, Tennessee
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8
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Yang X, Dai J, Wu C, Liu Z. Alzheimer's Disease and Cancer: Common Targets. Mini Rev Med Chem 2024; 24:983-1000. [PMID: 38037912 DOI: 10.2174/0113895575263108231031132404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/13/2023] [Accepted: 10/09/2023] [Indexed: 12/02/2023]
Abstract
There is growing epidemiologic evidence of an inverse association between cancer and AD. In addition, both cell survival and death are regulated by the same signaling pathways, and their abnormal regulation may be implicated in the occurrence and development of cancer and AD. Research shows that there may be a common molecular mechanism between cancer and AD. This review will discuss the role of GSK3, DAPK1, PP2A, P53 and CB2R in the pathogenesis of cancer and AD and describe the current research status of drug development based on these targets.
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Affiliation(s)
- Xueqing Yang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Jinlian Dai
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Chenglong Wu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Zongliang Liu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
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9
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Vasincu A, Rusu RN, Ababei DC, Neamțu M, Arcan OD, Macadan I, Beșchea Chiriac S, Bild W, Bild V. Exploring the Therapeutic Potential of Cannabinoid Receptor Antagonists in Inflammation, Diabetes Mellitus, and Obesity. Biomedicines 2023; 11:1667. [PMID: 37371762 DOI: 10.3390/biomedicines11061667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/31/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Recently, research has greatly expanded the knowledge of the endocannabinoid system (ECS) and its involvement in several therapeutic applications. Cannabinoid receptors (CBRs) are present in nearly every mammalian tissue, performing a vital role in different physiological processes (neuronal development, immune modulation, energy homeostasis). The ECS has an essential role in metabolic control and lipid signaling, making it a potential target for managing conditions such as obesity and diabetes. Its malfunction is closely linked to these pathological conditions. Additionally, the immunomodulatory function of the ECS presents a promising avenue for developing new treatments for various types of acute and chronic inflammatory conditions. Preclinical investigations using peripherally restricted CBR antagonists that do not cross the BBB have shown promise for the treatment of obesity and metabolic diseases, highlighting the importance of continuing efforts to discover novel molecules with superior safety profiles. The purpose of this review is to examine the roles of CB1R and CB2Rs, as well as their antagonists, in relation to the above-mentioned disorders.
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Affiliation(s)
- Alexandru Vasincu
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Răzvan-Nicolae Rusu
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Daniela-Carmen Ababei
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Monica Neamțu
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Oana Dana Arcan
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Ioana Macadan
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Sorin Beșchea Chiriac
- Department of Toxicology, "Ion Ionescu de la Brad" University of Life Sciences, 8 M. Sadoveanu Alley, 700489 Iasi, Romania
| | - Walther Bild
- Department of Physiology, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
- Center of Biomedical Research of the Romanian Academy, 700506 Iasi, Romania
| | - Veronica Bild
- Department of Pharmacodynamics and Clinical Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
- Center of Biomedical Research of the Romanian Academy, 700506 Iasi, Romania
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
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10
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Grabon W, Rheims S, Smith J, Bodennec J, Belmeguenai A, Bezin L. CB2 receptor in the CNS: from immune and neuronal modulation to behavior. Neurosci Biobehav Rev 2023; 150:105226. [PMID: 37164044 DOI: 10.1016/j.neubiorev.2023.105226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/20/2023] [Accepted: 05/06/2023] [Indexed: 05/12/2023]
Abstract
Despite low levels of cannabinoid receptor type 2 (CB2R) expression in the central nervous system in human and rodents, a growing body of evidence shows CB2R involvement in many processes at the behavioral level, through both immune and neuronal modulations. Recent in vitro and in vivo evidence have highlighted the complex role of CB2R under physiological and inflammatory conditions. Under neuroinflammatory states, its activation seems to protect the brain and its functions, making it a promising target in a wide range of neurological disorders. Here, we provide a complete and updated overview of CB2R function in the central nervous system of rodents, spanning from modulation of immune function in microglia but also in other cell types, to behavior and neuronal activity, in both physiological and neuroinflammatory contexts.
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Affiliation(s)
- Wanda Grabon
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France.
| | - Sylvain Rheims
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France; Department of Functional Neurology and Epileptology, Hospices Civils de Lyon - France
| | - Jonathon Smith
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France
| | - Jacques Bodennec
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France
| | - Amor Belmeguenai
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France
| | - Laurent Bezin
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France.
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11
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Nayak AP, Loblundo C, Bielory L. Immunomodulatory Actions of Cannabinoids: Clinical Correlates and Therapeutic Opportunities for Allergic Inflammation. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY. IN PRACTICE 2023; 11:449-457. [PMID: 36280137 PMCID: PMC9918686 DOI: 10.1016/j.jaip.2022.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/05/2022] [Accepted: 10/09/2022] [Indexed: 11/06/2022]
Abstract
Endogenously produced cannabinoids as well as phytocannabinoids broadly exhibit anti-inflammatory actions. Recent emergence of cannabis for multiple medical issues combined with reports on potent immunomodulatory actions of distinct components has underscored the therapeutic potential of cannabis. Although synthetic cannabinoids that are based on structural similarities to the existing class of cannabinoids have been on the rise, their application in therapeutics have been limited owing to toxicity concerns. Herein, we review the current literature that details the immunomodulatory actions of cannabinoids. Further, we highlight the complexities of cannabinoid biology and examine the potential inflammatory risks associated with the use of cannabis including potential for toxic interactions between distinct constituents of cannabis.
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Affiliation(s)
- Ajay P Nayak
- Department of Medicine, Thomas Jefferson University, Philadelphia, Pa; Center for Translational Medicine; Division of Pulmonary Allergy and Critical Care Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pa.
| | - Cali Loblundo
- Department of Medicine, Thomas Jefferson University, Philadelphia, Pa; Center for Translational Medicine; Division of Pulmonary Allergy and Critical Care Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pa
| | - Leonard Bielory
- Department of Medicine, Thomas Jefferson University, Philadelphia, Pa; Department of Medicine, Hackensack Meridian School of Medicine, Nutley, NJ; Rutgers University Center for Environmental Prediction, New Brunswick, NJ; Center for Aerobiological Research, Kean University, Union, NJ.
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12
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Martinez Ramirez CE, Ruiz-Pérez G, Stollenwerk TM, Behlke C, Doherty A, Hillard CJ. Endocannabinoid signaling in the central nervous system. Glia 2023; 71:5-35. [PMID: 36308424 PMCID: PMC10167744 DOI: 10.1002/glia.24280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 09/02/2022] [Accepted: 09/29/2022] [Indexed: 11/07/2022]
Abstract
It is hard to overestimate the influence of the endocannabinoid signaling (ECS) system on central nervous system (CNS) function. In the 40 years since cannabinoids were found to trigger specific cell signaling cascades, studies of the ECS system continue to cause amazement, surprise, and confusion! CB1 cannabinoid receptors are expressed widely in the CNS and regulate cell-cell communication via effects on the release of both neurotransmitters and gliotransmitters. CB2 cannabinoid receptors are difficult to detect in the CNS but seem to "punch above their weight" as compounds targeting these receptors have significant effects on inflammatory state and behavior. Positive and negative allosteric modulators for both receptors have been identified and examined in preclinical studies. Concentrations of the endocannabinoid ligands, N-arachidonoylethanolamine and 2-arachidonoylglycerol (2-AG), are regulated by a combination of enzymatic synthesis and degradation and inhibitors of these processes are available and making their way into clinical trials. Importantly, ECS regulates many essential brain functions, including regulation of reward, anxiety, inflammation, motor control, and cellular development. While the field is on the cusp of preclinical discoveries providing impactful clinical and therapeutic insights into many CNS disorders, there is still much to be learned about this remarkable and versatile modulatory system.
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Affiliation(s)
- César E Martinez Ramirez
- Neuroscience Research Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Gonzalo Ruiz-Pérez
- Neuroscience Research Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Todd M Stollenwerk
- Neuroscience Research Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Christina Behlke
- Neuroscience Research Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Ashley Doherty
- Neuroscience Research Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Cecilia J Hillard
- Neuroscience Research Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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13
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Honig MG, Del Mar NA, Moore BM, Reiner A. Raloxifene Mitigates Emotional Deficits after Mild Traumatic Brain Injury in Mice. Neurotrauma Rep 2022; 3:534-544. [DOI: 10.1089/neur.2022.0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Affiliation(s)
- Marcia G. Honig
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Nobel A. Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Bob M. Moore
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
- Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
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14
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Rasiah PK, Jha KA, Gentry J, Del Mar NA, Townsend T, Torgbe KE, Reiner A, Gangaraju R. A Long-Term Safety and Efficacy Report on Intravitreal Delivery of Adipose Stem Cells and Secretome on Visual Deficits After Traumatic Brain Injury. Transl Vis Sci Technol 2022; 11:1. [PMID: 36180031 PMCID: PMC9547363 DOI: 10.1167/tvst.11.10.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/30/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose We compared intravitreal injection of human adipose stem cell concentrated conditioned media (ASC-CCM) to injection of live ASCs for their long-term safety and effectiveness against the visual deficits of mild traumatic brain injury (mTBI). Methods We first tested different intravitreal ASC doses for safety. Other C57BL/6 mice then received focal cranial blast mTBI and were injected with the safe ASC dose (1000 cells/eye), ASC-CCM (∼200 ng protein/eye), or saline solution. At five and 10 months after blast injury, visual, molecular, and histological assessments evaluated treatment efficacy. Histological evaluation of eyes and other organs at 10 months after blast injury assessed safety. Results Human ASCs at 1000 cells/eye were found to be safe, with >10,000 cells causing retinal damage. Blast-injured mice showed significant vision deficits compared to sham blast mice up to 10 months. Blast mice receiving ASC or ASC-CCM showed improved vision at five months but marginal effects at 10 months, correlated with changes in glial fibrillary acidic protein and proinflammatory gene expression in retina. Immunostaining for human IgG failed to detect ASCs in retina. Peripheral organs examined histologically at 10 months after blast injury were normal. Conclusions Intravitreal injection of ASCs or ASC-CCM is safe and effective against the visual deficits of mTBI. Considering the unimproved glial response and the risk of retinal damage with live cells, our studies suggest that ASC-CCM has better safety and effectiveness than live cells for the treatment of visual dysfunction in mTBI. Translational Relevance This study demonstrates the safety and efficacy of mesenchymal stem cell-based therapeutics, supporting them for phase 1 clinical studies.
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Affiliation(s)
- Pratheepa Kumari Rasiah
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Kumar Abhiram Jha
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Jordy Gentry
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Nobel A. Del Mar
- Department of Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Tanisha Townsend
- Department of Pathology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Kwame E. Torgbe
- Department of Pathology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Anton Reiner
- Department of Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Rajashekhar Gangaraju
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
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15
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Honig MG, Del Mar NA, Henderson DL, O'Neal D, Yammanur M, Cox R, Li C, Perry AM, Moore BM, Reiner A. Raloxifene, a cannabinoid type-2 receptor inverse agonist, mitigates visual deficits and pathology and modulates microglia after ocular blast. Exp Eye Res 2022; 218:108966. [PMID: 35143834 DOI: 10.1016/j.exer.2022.108966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 01/04/2022] [Accepted: 01/24/2022] [Indexed: 11/19/2022]
Abstract
Visual deficits after ocular blast injury (OBI) are common, but pharmacological approaches to improve long-term outcomes have not been identified. Blast forces frequently damage the retina and optic nerves, and work on experimental animals has shown the pro-inflammatory actions of microglia can further exacerbate such injuries. Cannabinoid type-2 receptor (CB2) inverse agonists specifically target activated microglia, biasing them away from the harmful pro-inflammatory M1 state toward the helpful reparative M2 state. We previously found that treating mice with CB2 inverse agonists after traumatic brain injury, produced by either focal cranial air blast or dorsal cranial impact, greatly attenuated the visual deficits and pathology that otherwise resulted. Here we examined the consequences of single and repeat OBI and the benefit provided by raloxifene, an FDA-approved estrogen receptor drug that possesses noteworthy CB2 inverse agonism. After single OBI, although the amplitudes of the A- and B-waves of the electroretinogram and pupil light response appeared to be normal, the mice showed hints of deficits in contrast sensitivity and visual acuity, a trend toward optic nerve axon loss, and significantly increased light aversion, which were reversed by 2 weeks of daily treatment with raloxifene. Mice subjected to repeat OBI (5 blasts spaced 1 min apart), exhibited more severe visual deficits, including decreases in contrast sensitivity, visual acuity, the amplitudes of the A- and B-waves of the electroretinogram, light aversion, and resting pupil diameter (i.e. hyperconstriction), accompanied by the loss of photoreceptor cells and optic nerve axons, nearly all of which were mitigated by raloxifene. Interestingly, optic nerve axon abundance was strongly correlated with contrast sensitivity and visual acuity across all groups of experimental mice in the repeat OBI study, suggesting optic nerve axon loss with rOBI and its attenuation with raloxifene are associated with the extent of these two deficits while photoreceptor abundance was highly correlated with A-wave amplitude and resting pupil size, suggesting a prominent role for photoreceptors in these two deficits. Quantitative PCR (qPCR) showed levels of M1-type microglial markers (e.g. iNOS, IL1β, TNFα, and CD32) in retina, optic nerve, and thalamus were increased 3 days after repeat OBI. With raloxifene treatment, the overall expression of M1 markers was more similar to that in sham mice. Raloxifene treatment was also associated with the elevation of IL10 transcripts in all three tissues compared to repeat OBI alone, but the results for the three other M2 microglial markers we examined were more varied. Taken together, the qPCR results suggest that raloxifene benefit for visual function and pathology was associated with a lessening of the pro-inflammatory actions of microglia. The benefit we find for raloxifene following OBI provides a strong basis for phase-2 efficacy testing in human clinical trials for treating ocular injury.
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Affiliation(s)
- Marcia G Honig
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Nobel A Del Mar
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Desmond L Henderson
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Dylan O'Neal
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Meghna Yammanur
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Rachel Cox
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Chunyan Li
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Aaron M Perry
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Bob M Moore
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Anton Reiner
- Department of Anatomy and Neurobiology(,) the University of Tennessee Health Science Center, Memphis, TN, 38163, USA; Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
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16
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The Endocannabinoid System in Glial Cells and Their Profitable Interactions to Treat Epilepsy: Evidence from Animal Models. Int J Mol Sci 2021; 22:ijms222413231. [PMID: 34948035 PMCID: PMC8709154 DOI: 10.3390/ijms222413231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 12/11/2022] Open
Abstract
Epilepsy is one of the most common neurological conditions. Yearly, five million people are diagnosed with epileptic-related disorders. The neuroprotective and therapeutic effect of (endo)cannabinoid compounds has been extensively investigated in several models of epilepsy. Therefore, the study of specific cell-type-dependent mechanisms underlying cannabinoid effects is crucial to understanding epileptic disorders. It is estimated that about 100 billion neurons and a roughly equal number of glial cells co-exist in the human brain. The glial population is in charge of neuronal viability, and therefore, their participation in brain pathophysiology is crucial. Furthermore, glial malfunctioning occurs in a wide range of neurological disorders. However, little is known about the impact of the endocannabinoid system (ECS) regulation over glial cells, even less in pathological conditions such as epilepsy. In this review, we aim to compile the existing knowledge on the role of the ECS in different cell types, with a particular emphasis on glial cells and their impact on epilepsy. Thus, we propose that glial cells could be a novel target for cannabinoid agents for treating the etiology of epilepsy and managing seizure-like disorders.
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17
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Honig MG, Del Mar NA, Henderson DL, O'Neal D, Doty JB, Cox R, Li C, Perry AM, Moore BM, Reiner A. Raloxifene Modulates Microglia and Rescues Visual Deficits and Pathology After Impact Traumatic Brain Injury. Front Neurosci 2021; 15:701317. [PMID: 34776838 PMCID: PMC8585747 DOI: 10.3389/fnins.2021.701317] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 09/07/2021] [Indexed: 11/29/2022] Open
Abstract
Mild traumatic brain injury (TBI) involves widespread axonal injury and activation of microglia, which initiates secondary processes that worsen the TBI outcome. The upregulation of cannabinoid type-2 receptors (CB2) when microglia become activated allows CB2-binding drugs to selectively target microglia. CB2 inverse agonists modulate activated microglia by shifting them away from the harmful pro-inflammatory M1 state toward the helpful reparative M2 state and thus can stem secondary injury cascades. We previously found that treatment with the CB2 inverse agonist SMM-189 after mild TBI in mice produced by focal cranial blast rescues visual deficits and the optic nerve axon loss that would otherwise result. We have further shown that raloxifene, which is Food and Drug Administration (FDA)-approved as an estrogen receptor modulator to treat osteoporosis, but also possesses CB2 inverse agonism, yields similar benefit in this TBI model through its modulation of microglia. As many different traumatic events produce TBI in humans, it is widely acknowledged that diverse animal models must be used in evaluating possible therapies. Here we examine the consequences of TBI created by blunt impact to the mouse head for visual function and associated pathologies and assess raloxifene benefit. We found that mice subjected to impact TBI exhibited decreases in contrast sensitivity and the B-wave of the electroretinogram, increases in light aversion and resting pupil diameter, and optic nerve axon loss, which were rescued by daily injection of raloxifene at 5 or 10 mg/ml for 2 weeks. Raloxifene treatment was associated with reduced M1 activation and/or enhanced M2 activation in retina, optic nerve, and optic tract after impact TBI. Our results suggest that the higher raloxifene dose, in particular, may be therapeutic for the optic nerve by enhancing the phagocytosis of axonal debris that would otherwise promote inflammation, thereby salvaging less damaged axons. Our current work, together with our prior studies, shows that microglial activation drives secondary injury processes after both impact and cranial blast TBI and raloxifene mitigates microglial activation and visual system injury in both cases. The results thus provide a strong basis for phase 2 human clinical trials evaluating raloxifene as a TBI therapy.
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Affiliation(s)
- Marcia G Honig
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Nobel A Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Desmond L Henderson
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Dylan O'Neal
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - John B Doty
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Rachel Cox
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Chunyan Li
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Aaron M Perry
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Bob M Moore
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, TN, United States
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18
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Mondal K, Takahashi H, Cole J, Del Mar NA, Li C, Stephenson DJ, Allegood J, Cowart LA, Chalfant CE, Reiner A, Mandal N. Systemic Elevation of n-3 Polyunsaturated Fatty Acids (n-3-PUFA) Is Associated with Protection against Visual, Motor, and Emotional Deficits in Mice following Closed-Head Mild Traumatic Brain Injury. Mol Neurobiol 2021; 58:5564-5580. [PMID: 34365584 DOI: 10.1007/s12035-021-02501-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 07/17/2021] [Indexed: 12/30/2022]
Abstract
Traumatic brain injury (TBI) causes neuroinflammation and neurodegeneration leading to various pathological complications such as motor and sensory (visual) deficits, cognitive impairment, and depression. N-3 polyunsaturated fatty acid (n-3 PUFA) containing lipids are known to be anti-inflammatory, whereas the sphingolipid, ceramide (Cer), is an inducer of neuroinflammation and degeneration. Using Fat1+-transgenic mice that contain elevated levels of systemic n-3 PUFA, we tested whether they are resistant to mild TBI-mediated sensory-motor and emotional deficits by subjecting Fat1-transgenic mice and their WT littermates to focal cranial air blast (50 psi) or sham blast (0 psi, control). We observed that visual function in WT mice was reduced significantly following TBI but not in Fat1+-blast animals. We also found Fat1+-blast mice were resistant to the decline in motor functions, depression, and fear-producing effects of blast, as well as the reduction in the area of oculomotor nucleus and increase in activated microglia in the optic tract in brain sections seen following blast in WT mice. Lipid and gene expression analyses confirmed an elevated level of the n-3 PUFA eicosapentaenoic acid (EPA) in the plasma and brain, blocking of TBI-mediated increase of Cer in the brain, and decrease in TBI-mediated induction of Cer biosynthetic and inflammatory gene expression in the brain of the Fat1+ mice. Our results demonstrate that suppression of ceramide biosynthesis and inflammatory factors in Fat1+-transgenic mice is associated with significant protection against the visual, motor, and emotional deficits caused by mild TBI. This study suggests that n-3 PUFA (especially, EPA) has a promising therapeutic role in preventing neurodegeneration after TBI.
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Affiliation(s)
- Koushik Mondal
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Haruka Takahashi
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA.,Department of Animal Science, Iwate University, Morioka, Japan
| | - Jerome Cole
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Nobel A Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Chunyan Li
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Daniel J Stephenson
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, 33620, USA
| | - Jeremy Allegood
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, 23219, USA
| | - L Ashley Cowart
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, 23219, USA.,Hunter Holmes McGuire VA Medical Center, Richmond, VA, 23249, USA
| | - Charles E Chalfant
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, 33620, USA.,The Moffitt Cancer Center, Tampa, FL, 33620, USA.,Research Service, James A. Haley Veterans Hospital, Tampa, FL, 33612, USA
| | - Anton Reiner
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA.,Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA
| | - Nawajes Mandal
- Department of Ophthalmology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA. .,Department of Anatomy and Neurobiology, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA. .,Department of Pharmaceutical Sciences, College of Pharmacy, The University of Tennessee Health Science Centre, TN, 38163, Memphis, USA. .,Memphis VA Medical Center, Memphis, TN, 38104, USA.
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19
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Dependence of visual and cognitive outcomes on animal holder configuration in a rodent model of blast overpressure exposure. Vision Res 2021; 188:162-173. [PMID: 34333201 DOI: 10.1016/j.visres.2021.07.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 05/24/2021] [Accepted: 07/14/2021] [Indexed: 02/04/2023]
Abstract
Blast-induced traumatic brain injury is the signature injury of modern military conflicts. To more fully understand the effects of blast exposure, we placed rats in different holder configurations, exposed them to blast overpressure, and assessed the degree of eye and brain injury. Anesthetized Long-Evans rats received blast exposures directed at the head (63 kPa, 195 dB-SPL) in either an "open holder" (head and neck exposed; n = 7), or an "enclosed holder" (window for blast exposure to eye; n = 15) and were compared to non-blast exposed (control) rats (n = 22). Outcomes included optomotor response (OMR), electroretinography (ERG), and spectral domain optical coherence tomography (SD-OCT) at 2, 4, and 6 months post-blast, and cognitive function (Y-maze) at 3 months. Spatial frequency and contrast sensitivity were reduced in ipsilateral blast-exposed eyes in both holders (p < 0.01), while contralateral eyes showed greater deficits with the enclosed holder (p < 0.05). Thinner retinas (p < 0.001) and reduced ERG a- and b- wave amplitudes (p < 0.05) were observed for both ipsilateral and contralateral eyes with the enclosed, but not the open, holder. Rats in the open holder showed cognitive deficits compared to rats in the enclosed holder (p < 0.05). Overall, the animal holder configuration used in blast exposure studies can significantly affect outcomes. Enclosed holders may cause secondary damage to the contralateral eye by concussive injury or blast wave reflection off the holder wall. Open holders may damage the brain via rapid head movement (contrecoup injury). These results highlight additional factors to be considered when evaluating patients with blast exposure or developing models of blast injury.
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20
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Ferrisi R, Ceni C, Bertini S, Macchia M, Manera C, Gado F. Medicinal Chemistry approach, pharmacology and neuroprotective benefits of CB 2R modulators in neurodegenerative diseases. Pharmacol Res 2021; 170:105607. [PMID: 34089867 DOI: 10.1016/j.phrs.2021.105607] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 03/12/2021] [Accepted: 04/06/2021] [Indexed: 12/01/2022]
Abstract
In the last decades, cannabinoid receptor 2 (CB2R) has continued to receive attention as a key therapeutic target in neuroprotection. Indeed, several findings highlight the neuroprotective effects of CB2R through suppression of both neuronal excitability and reactive microglia. Additionally, CB2R seems to be a more promising target than cannabinoid receptor 1 (CB1R) thanks to the lack of central side effects, its lower expression levels in the central nervous system (CNS), and its inducibility, since its expression enhances quickly in the brain following pathological conditions. This review aims to provide a thorough overview of the main natural and synthetic selective CB2R modulators, their chemical classification and their potential therapeutic usefulness in neuroprotection, a crucial aspect for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Rebecca Ferrisi
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy.
| | - Costanza Ceni
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy.
| | - Simone Bertini
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy.
| | - Marco Macchia
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy.
| | | | - Francesca Gado
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy.
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21
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Microglia: A Potential Drug Target for Traumatic Axonal Injury. Neural Plast 2021; 2021:5554824. [PMID: 34093701 PMCID: PMC8163545 DOI: 10.1155/2021/5554824] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/06/2021] [Accepted: 04/26/2021] [Indexed: 12/20/2022] Open
Abstract
Traumatic axonal injury (TAI) is a major cause of death and disability among patients with severe traumatic brain injury (TBI); however, no effective therapies have been developed to treat this disorder. Neuroinflammation accompanying microglial activation after TBI is likely to be an important factor in TAI. In this review, we summarize the current research in this field, and recent studies suggest that microglial activation plays an important role in TAI development. We discuss several drugs and therapies that may aid TAI recovery by modulating the microglial phenotype following TBI. Based on the findings of recent studies, we conclude that the promotion of active microglia to the M2 phenotype is a potential drug target for the treatment of TAI.
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22
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Cannabinoid receptor type 2 ligands: an analysis of granted patents since 2010. Pharm Pat Anal 2021; 10:111-163. [DOI: 10.4155/ppa-2021-0002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The G-protein-coupled cannabinoid receptor type 2 (CB2R) is a key element of the endocannabinoid (EC) system. EC/CB2R signaling has significant therapeutic potential in major pathologies affecting humans such as allergies, neurodegenerative disorders, inflammation or ocular diseases. CB2R agonism exerts anti-inflammatory and tissue protective effects in preclinical animal models of cardiovascular, gastrointestinal, liver, kidney, lung and neurodegenerative disorders. Existing ligands can be subdivided into endocannabinoids, cannabinoid-like and synthetic CB2R ligands that possess various degrees of potency on and selectivity against the cannabinoid receptor type 1. This review is an account of granted CB2R ligand patents from 2010 up to the present, which were surveyed using Derwent Innovation®.
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23
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Evans LP, Roghair AM, Gilkes NJ, Bassuk AG. Visual Outcomes in Experimental Rodent Models of Blast-Mediated Traumatic Brain Injury. Front Mol Neurosci 2021; 14:659576. [PMID: 33935648 PMCID: PMC8081965 DOI: 10.3389/fnmol.2021.659576] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/18/2021] [Indexed: 11/24/2022] Open
Abstract
Blast-mediated traumatic brain injuries (bTBI) cause long-lasting physical, cognitive, and psychological disorders, including persistent visual impairment. No known therapies are currently utilized in humans to lessen the lingering and often serious symptoms. With TBI mortality decreasing due to advancements in medical and protective technologies, there is growing interest in understanding the pathology of visual dysfunction after bTBI. However, this is complicated by numerous variables, e.g., injury location, severity, and head and body shielding. This review summarizes the visual outcomes observed by various, current experimental rodent models of bTBI, and identifies data showing that bTBI activates inflammatory and apoptotic signaling leading to visual dysfunction. Pharmacologic treatments blocking inflammation and cell death pathways reported to alleviate visual deficits in post-bTBI animal models are discussed. Notably, techniques for assessing bTBI outcomes across exposure paradigms differed widely, so we urge future studies to compare multiple models of blast injury, to allow data to be directly compared.
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Affiliation(s)
- Lucy P. Evans
- Department of Pediatrics, University of Iowa, Iowa City, IA, United States
- Medical Scientist Training Program, University of Iowa, Iowa City, IA, United States
| | - Ariel M. Roghair
- Department of Pediatrics, University of Iowa, Iowa City, IA, United States
| | - Noah J. Gilkes
- Department of Pediatrics, University of Iowa, Iowa City, IA, United States
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24
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George AK, Behera J, Homme RP, Tyagi N, Tyagi SC, Singh M. Rebuilding Microbiome for Mitigating Traumatic Brain Injury: Importance of Restructuring the Gut-Microbiome-Brain Axis. Mol Neurobiol 2021; 58:3614-3627. [PMID: 33774742 PMCID: PMC8003896 DOI: 10.1007/s12035-021-02357-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/10/2021] [Indexed: 12/20/2022]
Abstract
Traumatic brain injury (TBI) is a damage to the brain from an external force that results in temporary or permanent impairment in brain functions. Unfortunately, not many treatment options are available to TBI patients. Therefore, knowledge of the complex interplay between gut microbiome (GM) and brain health may shed novel insights as it is a rapidly expanding field of research around the world. Recent studies show that GM plays important roles in shaping neurogenerative processes such as blood-brain-barrier (BBB), myelination, neurogenesis, and microglial maturation. In addition, GM is also known to modulate many aspects of neurological behavior and cognition; however, not much is known about the role of GM in brain injuries. Since GM has been shown to improve cellular and molecular functions via mitigating TBI-induced pathologies such as BBB permeability, neuroinflammation, astroglia activation, and mitochondrial dysfunction, herein we discuss how a dysbiotic gut environment, which in fact, contributes to central nervous system (CNS) disorders during brain injury and how to potentially ward off these harmful effects. We further opine that a better understanding of GM-brain (GMB) axis could help assist in designing better treatment and management strategies in future for the patients who are faced with limited options.
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Affiliation(s)
- Akash K George
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA.,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA
| | - Jyotirmaya Behera
- Bone Biology Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA
| | - Rubens P Homme
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA.,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA
| | - Neetu Tyagi
- Bone Biology Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA
| | - Suresh C Tyagi
- Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA
| | - Mahavir Singh
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA. .,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky, 40202, USA.
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25
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Alghamdi SS, Mustafa SM, Moore Ii BM. Synthesis and biological evaluation of a ring analogs of the selective CB2 inverse agonist SMM-189. Bioorg Med Chem 2021; 33:116035. [PMID: 33550084 DOI: 10.1016/j.bmc.2021.116035] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 12/23/2022]
Abstract
Microglia are the principle cell type driving sustained neuroinflammation in neurodegenerative diseases such as Alzheimer's, Parkinson's, and Multiple Sclerosis. Interestingly, microglia locked into a chronic M1 pro-inflammatory phenotype significantly up-regulate the cannabinoid receptor 2 (CB2) expression. Our approach to exploiting CB2 as a therapeutic target in neuroinflammatory diseases focuses on the development of selective CB2 inverse agonists to shift microglia bias to a M2 pro-wound healing phenotype. Herein we report work designed to refine the structure activity relationship of the 2,6-dihydroxy-biphenyl-aryl-methanone CB2 inverse agonist scaffold. A series of analogs of our lead compound SMM-189 were synthesized and measured for affinity/selectivity, potency, and efficacy in regulating cAMP production and β-arrestin recruitment. In this series compound 40 demonstrated a significant increase in potency and efficacy for cAMP stimulation compared to SMM-189. Akin to our lead SMM-189, this compound was highly efficacious in biasing microglia to an M2 pro-wound healing phenotype in LPS stimulated cell lines. These results advance our understanding of the structure-activity relationship of the 2,6-dihydroxy-biphenyl-aryl-methanone scaffold and provide further support for regulating microglia activation using CB2 inverse agonists.
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Affiliation(s)
- Sahar S Alghamdi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Suni M Mustafa
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Bob M Moore Ii
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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26
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Arun P, Rossetti F, DeMar JC, Wang Y, Batuure AB, Wilder DM, Gist ID, Morris AJ, Sabbadini RA, Long JB. Antibodies Against Lysophosphatidic Acid Protect Against Blast-Induced Ocular Injuries. Front Neurol 2020; 11:611816. [PMID: 33384658 PMCID: PMC7769950 DOI: 10.3389/fneur.2020.611816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/24/2020] [Indexed: 01/18/2023] Open
Abstract
Exposure to blast overpressure waves is implicated as the major cause of ocular injuries and resultant visual dysfunction in veterans involved in recent combat operations. No effective therapeutic strategies have been developed so far for blast-induced ocular dysfunction. Lysophosphatidic acid (LPA) is a bioactive phospholipid generated by activated platelets, astrocytes, choroidal plexus cells, and microglia and is reported to play major roles in stimulating inflammatory processes. The levels of LPA in the cerebrospinal fluid have been reported to increase acutely in patients with traumatic brain injury (TBI) as well as in a controlled cortical impact (CCI) TBI model in mice. In the present study, we have evaluated the efficacy of a single intravenous administration of a monoclonal LPA antibody (25 mg/kg) given at 1 h post-blast for protection against injuries to the retina and associated ocular dysfunctions. Our results show that a single 19 psi blast exposure significantly increased the levels of several species of LPA in blood plasma at 1 and 4 h post-blast. The anti-LPA antibody treatment significantly decreased glial cell activation and preserved neuronal cell morphology in the retina on day 8 after blast exposure. Optokinetic measurements indicated that anti-LPA antibody treatment significantly improved visual acuity in both eyes on days 2 and 6 post-blast exposure. Anti-LPA antibody treatment significantly increased rod photoreceptor and bipolar neuronal cell signaling in both eyes on day 7 post-blast exposure. These results suggest that blast exposure triggers release of LPAs, which play a major role promoting blast-induced ocular injuries, and that a single early administration of anti-LPA antibodies provides significant protection.
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Affiliation(s)
- Peethambaran Arun
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Franco Rossetti
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - James C DeMar
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Ying Wang
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Andrew B Batuure
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Donna M Wilder
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Irene D Gist
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Andrew J Morris
- Division of Cardiovascular Medicine, Lexington VA Medical Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Roger A Sabbadini
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Joseph B Long
- Blast-Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
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27
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Shultz SR, McDonald SJ, Corrigan F, Semple BD, Salberg S, Zamani A, Jones NC, Mychasiuk R. Clinical Relevance of Behavior Testing in Animal Models of Traumatic Brain Injury. J Neurotrauma 2020; 37:2381-2400. [DOI: 10.1089/neu.2018.6149] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Sandy R. Shultz
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
- Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia
| | - Stuart J. McDonald
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
- Department of Physiology, Anatomy, and Microbiology, La Trobe University, Melbourne, Victoria, Australia
| | - Frances Corrigan
- Department of Anatomy, University of South Australia, Adelaide, South Australia, Australia
| | - Bridgette D. Semple
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
- Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia
| | - Sabrina Salberg
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
| | - Akram Zamani
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
| | - Nigel C. Jones
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
- Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
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28
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Saloner R, Fields JA, Marcondes MCG, Iudicello JE, von Känel S, Cherner M, Letendre SL, Kaul M, Grant I. Methamphetamine and Cannabis: A Tale of Two Drugs and their Effects on HIV, Brain, and Behavior. J Neuroimmune Pharmacol 2020; 15:743-764. [PMID: 32929575 DOI: 10.1007/s11481-020-09957-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/10/2020] [Indexed: 12/12/2022]
Abstract
HIV infection and drug use intersect epidemiologically, and their combination can result in complex effects on brain and behavior. The extent to which drugs affect the health of persons with HIV (PWH) depends on many factors including drug characteristics, use patterns, stage of HIV disease and its treatment, comorbid factors, and age. To consider the range of drug effects, we have selected two that are in common use by PWH: methamphetamine and cannabis. We compare the effects of methamphetamine with those of cannabis, to illustrate how substances may potentiate, worsen, or even buffer the effects of HIV on the CNS. Data from human, animal, and ex vivo studies provide insights into how these drugs have differing effects on the persistent inflammatory state that characterizes HIV infection, including effects on viral replication, immune activation, mitochondrial function, gut permeability, blood brain barrier integrity, glia and neuronal signaling. Moving forward, we consider how these mechanistic insights may inform interventions to improve brain outcomes in PWH. This review summarizes literature from clinical and preclinical studies demonstrating the adverse effects of METH, as well as the potentially beneficial effects of cannabis, on the interacting systemic (e.g., gut barrier leakage/microbial translocation, immune activation, inflammation) and CNS-specific (e.g., glial activation/neuroinflammation, neural injury, mitochondrial toxicity/oxidative stress) mechanisms underlying HIV-associated neurocognitive disorders.
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Affiliation(s)
- Rowan Saloner
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA. .,Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California, San Diego , San Diego, CA, USA.
| | - Jerel Adam Fields
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA
| | | | - Jennifer E Iudicello
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA
| | - Sofie von Känel
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA
| | - Mariana Cherner
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA
| | - Scott L Letendre
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA
| | - Marcus Kaul
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA.,Division of Biomedical Sciences, University of California, Riverside, Riverside, CA, USA
| | - Igor Grant
- Department of Psychiatry, HIV Neurobehavioral Research Program, University of California, San Diego, San Diego, CA, USA
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29
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The Treatment of Cognitive, Behavioural and Motor Impairments from Brain Injury and Neurodegenerative Diseases through Cannabinoid System Modulation-Evidence from In Vivo Studies. J Clin Med 2020; 9:jcm9082395. [PMID: 32726998 PMCID: PMC7464236 DOI: 10.3390/jcm9082395] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/19/2020] [Accepted: 07/23/2020] [Indexed: 12/20/2022] Open
Abstract
Neurological disorders such as neurodegenerative diseases or traumatic brain injury are associated with cognitive, motor and behavioural changes that influence the quality of life of the patients. Although different therapeutic strategies have been developed and tried until now to decrease the neurological decline, no treatment has been found to cure these pathologies. In the last decades, the implication of the endocannabinoid system in the neurological function has been extensively studied, and the cannabinoids have been tried as a new promising potential treatment. In this study, we aimed to overview the recent available literature regarding in vivo potential of natural and synthetic cannabinoids with underlying mechanisms of action for protecting against cognitive decline and motor impairments. The results of studies on animal models showed that cannabinoids in traumatic brain injury increase neurobehavioral function, working memory performance, and decrease the neurological deficit and ameliorate motor deficit through down-regulation of pro-inflammatory markers, oedema formation and blood–brain barrier permeability, preventing neuronal cell loss and up-regulating the levels of adherence junction proteins. In neurodegenerative diseases, the cannabinoids showed beneficial effects in decreasing the motor disability and disease progression by a complex mechanism targeting more signalling pathways further than classical receptors of the endocannabinoid system. In light of these results, the use of cannabinoids could be beneficial in traumatic brain injuries and multiple sclerosis treatment, especially in those patients who display resistance to conventional treatment.
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30
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Yu Y, Li L, Nguyen DT, Mustafa SM, Moore BM, Jiang J. Inverse Agonism of Cannabinoid Receptor Type 2 Confers Anti-inflammatory and Neuroprotective Effects Following Status Epileptics. Mol Neurobiol 2020; 57:2830-2845. [PMID: 32378121 DOI: 10.1007/s12035-020-01923-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 04/22/2020] [Indexed: 12/13/2022]
Abstract
Prolonged status epilepticus (SE) in humans causes high mortality and brain inflammation-associated neuronal injury and morbidity in survivors. Currently, the only effective treatment is to terminate the seizures swiftly to prevent brain damage. However, reliance on acute therapies alone would be imprudent due to the required short response time. Follow-on therapies that can be delivered well after the SE onset are in an urgent need. Cannabinoid receptor type 2 (CB2), a G protein-coupled receptor that can be expressed by activated brain microglia, has emerged as an appealing anti-inflammatory target for brain conditions. In the current study, we reported that the CB2 inverse agonism by our current lead compound SMM-189 largely prevented the rat primary microglia-mediated inflammation and showed moderate neuroprotection against N-methyl-D-aspartic acid (NMDA) receptor-mediated excitotoxicity in rat primary hippocampal cultures containing both neurons and glia. Using a classical mouse model of epilepsy, in which SE was induced by systemic administration of kainate (30 mg/kg, i.p.) and proceeded for 1 h, we demonstrated that SE downregulated the CB1 but slightly upregulated CB2 receptor in the hippocampus. Transient treatment with SMM-189 (6 mg/kg, i.p., b.i.d.) after the SE was interrupted by diazepam (10 mg/kg, i.p.) prevented the seizure-induced cytokine surge in the brain, neuronal death, and behavioral impairments 24 h after SE. Our results suggest that CB2 inverse agonism might provide an adjunctive anti-inflammatory therapy that can be delivered hours after SE onset, together with NMDA receptor blockers and first-line anti-convulsants, to reduce brain injury and functional deficits following prolonged seizures.
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Affiliation(s)
- Ying Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Lexiao Li
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Davis T Nguyen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Suni M Mustafa
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Bob M Moore
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Jianxiong Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
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31
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Keating CE, Browne KD, Duda JE, Cullen DK. Neurons in Subcortical Oculomotor Regions Are Vulnerable to Plasma Membrane Damage after Repetitive Diffuse Traumatic Brain Injury in Swine. J Neurotrauma 2020; 37:1918-1932. [PMID: 32178582 DOI: 10.1089/neu.2019.6738] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Oculomotor deficits, such as insufficiencies in accommodation, convergence, and saccades, are common following traumatic brain injury (TBI). Previous studies in patients with mild TBI attributed these deficits to insufficient activation of subcortical oculomotor nuclei, although the exact mechanism is unknown. A possible cause for neuronal dysfunction in these regions is biomechanically induced plasma membrane permeability. We used our established porcine model of head rotational TBI to investigate whether cell permeability changes occurred in subcortical oculomotor areas following single or repetitive TBI, with repetitive injuries separated by 15 min, 3 days, or 7 days. Swine were subjected to sham conditions or head rotational acceleration in the sagittal plane using a HYGE pneumatic actuator. Two hours prior to the final injury, the cell-impermeant dye Lucifer Yellow was injected into the ventricles to diffuse throughout the interstitial space to assess plasmalemmal permeability. Animals were sacrificed 15 min after the final injury for immunohistological analysis. Brain regions examined for cell membrane permeability included caudate, substantia nigra pars reticulata, superior colliculus, and cranial nerve oculomotor nuclei. We found that the distribution of permeabilized neurons varied depending on the number and spacing of injuries. Repetitive injuries separated by 15 min or 3 days resulted in the most permeability. Many permeabilized cells lost neuron-specific nuclear protein reactivity, although no neuronal loss occurred acutely after injury. Microglia contacted and appeared to begin phagocytosing permeabilized neurons in repetitively injured animals. These pathologies within oculomotor areas may mediate transient dysfunction and/or degeneration that may contribute to oculomotor deficits following diffuse TBI.
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Affiliation(s)
- Carolyn E Keating
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kevin D Browne
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - John E Duda
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA.,Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - D Kacy Cullen
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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32
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Honig MG, Dorian CC, Worthen JD, Micetich AC, Mulder IA, Sanchez KB, Pierce WF, Del Mar NA, Reiner A. Progressive long-term spatial memory loss following repeat concussive and subconcussive brain injury in mice, associated with dorsal hippocampal neuron loss, microglial phenotype shift, and vascular abnormalities. Eur J Neurosci 2020; 54:5844-5879. [PMID: 32090401 PMCID: PMC7483557 DOI: 10.1111/ejn.14711] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 02/18/2020] [Accepted: 02/19/2020] [Indexed: 12/14/2022]
Abstract
There is considerable concern about the long‐term deleterious effects of repeat head trauma on cognition, but little is known about underlying mechanisms and pathology. To examine this, we delivered four air blasts to the left side of the mouse cranium, a week apart, with an intensity that causes deficits when delivered singly and considered “concussive,” or an intensity that does not yield significant deficits when delivered singly and considered “subconcussive.” Neither repeat concussive nor subconcussive blast produced spatial memory deficits at 4 months, but both yielded deficits at 14 months, and dorsal hippocampal neuron loss. Hierarchical cluster analysis of dorsal hippocampal microglia across the three groups based on morphology and expression of MHCII, CX3CR1, CD68 and IBA1 revealed five distinct phenotypes. Types 1A and 1B microglia were more common in sham mice, linked to better neuron survival and memory, and appeared mildly activated. By contrast, 2B and 2C microglia were more common in repeat concussive and subconcussive mice, linked to poorer neuron survival and memory, and characterized by low expression levels and attenuated processes, suggesting they were de‐activated and dysfunctional. In addition, endothelial cells in repeat concussive mice exhibited reduced CD31 and eNOS expression, which was correlated with the prevalence of type 2B and 2C microglia. Our findings suggest that both repeat concussive and subconcussive head injury engender progressive pathogenic processes, possibly through sustained effects on microglia that over time lead to increased prevalence of dysfunctional microglia, adversely affecting neurons and blood vessels, and thereby driving neurodegeneration and memory decline.
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Affiliation(s)
- Marcia G Honig
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Conor C Dorian
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - John D Worthen
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Anthony C Micetich
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Isabelle A Mulder
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Katelyn B Sanchez
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - William F Pierce
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Nobel A Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, TN, USA
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33
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Neuro-Ophthalmic Injuries With Systemic Neurologic Injury or Traumatic Brain Injury in Operation Iraqi Freedom and Operation Enduring Freedom. J Neuroophthalmol 2020; 40:322-327. [DOI: 10.1097/wno.0000000000000913] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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34
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Tanaka M, Sackett S, Zhang Y. Endocannabinoid Modulation of Microglial Phenotypes in Neuropathology. Front Neurol 2020; 11:87. [PMID: 32117037 PMCID: PMC7033501 DOI: 10.3389/fneur.2020.00087] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/24/2020] [Indexed: 12/12/2022] Open
Abstract
Microglia, the resident immune cells of the central nervous system, mediate brain homeostasis by controlling neuronal proliferation/differentiation and synaptic activity. In response to external signals from neuropathological conditions, homeostatic (M0) microglia can adopt one of two activation states: the classical (M1) activation state, which secretes mediators of the proinflammatory response, and the alternative (M2) activation state, which presumably mediates the resolution of neuroinflammation and tissue repair/remodeling. Since chronic inflammatory activation of microglia is correlated with several neurodegenerative diseases, functional modulation of microglial phenotypes has been considered as a potential therapeutic strategy. The endocannabinoid (eCB) system, composed of cannabinoid receptors and ligands and their metabolic/biosynthetic enzymes, has been shown to activate anti-inflammatory signaling pathways that modulate immune cell functions. Growing evidence has demonstrated that endogenous, synthetic, and plant-derived eCB agonists possess therapeutic effects on several neuropathologies; however, the molecular mechanisms that mediate the anti-inflammatory effects have not yet been identified. Over the last decade, it has been revealed that the eCB system modulates microglial activation and population. In this review, we thoroughly examine recent studies on microglial phenotype modulation by eCB in neuroinflammatory and neurodegenerative disease conditions. We hypothesize that cannabinoid 2 receptor (CB2R) signaling shifts the balance of expression between neuroinflammatory (M1-type) genes, neuroprotective (M2-type) genes, and homeostatic (M0-type) genes toward the latter two gene expressions, by which microglia acquire therapeutic functionality.
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Affiliation(s)
- Mikiei Tanaka
- Department of Anatomy, Physiology and Genetics, Uniformed Services University Health Sciences, Bethesda, MD, United States
| | - Scott Sackett
- Department of Anatomy, Physiology and Genetics, Uniformed Services University Health Sciences, Bethesda, MD, United States
| | - Yumin Zhang
- Department of Anatomy, Physiology and Genetics, Uniformed Services University Health Sciences, Bethesda, MD, United States
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35
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Kelly R, Joers V, Tansey MG, McKernan DP, Dowd E. Microglial Phenotypes and Their Relationship to the Cannabinoid System: Therapeutic Implications for Parkinson's Disease. Molecules 2020; 25:molecules25030453. [PMID: 31973235 PMCID: PMC7037317 DOI: 10.3390/molecules25030453] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 12/11/2022] Open
Abstract
Parkinson’s disease is a neurodegenerative disorder, the motor symptoms of which are associated classically with Lewy body formation and nigrostriatal degeneration. Neuroinflammation has been implicated in the progression of this disease, by which microglia become chronically activated in response to α-synuclein pathology and dying neurons, thereby acquiring dishomeostatic phenotypes that are cytotoxic and can cause further neuronal death. Microglia have a functional endocannabinoid signaling system, expressing the cannabinoid receptors in addition to being capable of synthesizing and degrading endocannabinoids. Alterations in the cannabinoid system—particularly an upregulation in the immunomodulatory CB2 receptor—have been demonstrated to be related to the microglial activation state and hence the microglial phenotype. This paper will review studies that examine the relationship between the cannabinoid system and microglial activation, and how this association could be manipulated for therapeutic benefit in Parkinson’s disease.
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Affiliation(s)
- Rachel Kelly
- Pharmacology & Therapeutics, National University of Ireland, H91 W5P7 Galway, Ireland; (R.K.); (D.P.M.)
| | - Valerie Joers
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32611, USA; (V.J.); (M.G.T.)
| | - Malú G. Tansey
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32611, USA; (V.J.); (M.G.T.)
- Center for Translation Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, FL 32611, USA
| | - Declan P. McKernan
- Pharmacology & Therapeutics, National University of Ireland, H91 W5P7 Galway, Ireland; (R.K.); (D.P.M.)
| | - Eilís Dowd
- Pharmacology & Therapeutics, National University of Ireland, H91 W5P7 Galway, Ireland; (R.K.); (D.P.M.)
- Correspondence:
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36
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Honig MG, Del Mar NA, Henderson DL, Ragsdale TD, Doty JB, Driver JH, Li C, Fortugno AP, Mitchell WM, Perry AM, Moore BM, Reiner A. Amelioration of visual deficits and visual system pathology after mild TBI via the cannabinoid Type-2 receptor inverse agonism of raloxifene. Exp Neurol 2019; 322:113063. [DOI: 10.1016/j.expneurol.2019.113063] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/09/2019] [Accepted: 09/07/2019] [Indexed: 11/29/2022]
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37
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Desai A, Chen H, Kim HY. Multiple Mild Traumatic Brain Injuries Lead to Visual Dysfunction in a Mouse Model. J Neurotrauma 2019; 37:286-294. [PMID: 31530220 DOI: 10.1089/neu.2019.6602] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Visual dysfunction is a common occurrence after traumatic brain injury (TBI). We investigated in this study effects of single or multiple mild TBI on visual function in mice using a closed head injury model that permits unconstrained head movement after impact. Adult mice were briefly anesthetized with isoflurane and given one or three mild TBI with the closed head injury by mechanically engineered rotational acceleration (CHIMERA) device with an interinjury interval of 24 h. Mice were then tested in the Morris water maze, visual cliff, and open field tests from day 19 to day 32 and for visual evoked potential at 5 weeks after the last injury and euthanized. Mice with multiple TBI showed impaired performance in the visible platform water maze test and had increased errors in the visual cliff test. Further, there was a graded difference in visual evoked potential, with the single injury mice showing modest reduction in N1 amplitude whereas the multiple injuries produced significant reduction compared to sham and single injury groups. The optic tract of the injured mice showed increases in glial cell immunostaining. The increase in glial fibrillary acid protein immunostaining reached statistical significance for both injured groups whereas the ionized calcium binding adaptor molecule 1 immunostaining was only significantly increased in the optic tract of repeatedly injured mice. These results indicate that multiple injuries using CHIMERA may result in visual deficits, which can affect certain behavioral performances. The change in vision may be a useful marker when monitoring repeated TBI outcome and screening for protective agents from TBI.
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Affiliation(s)
- Abhishek Desai
- Laboratory of Molecular Signaling, NIAAA, NIH, Rockville, Maryland
| | - Huazhen Chen
- Laboratory of Molecular Signaling, NIAAA, NIH, Rockville, Maryland.,Center for Neuroscience and Regenerative Medicine at the Uniformed Services University of Health Sciences, Bethesda, Maryland
| | - Hee-Yong Kim
- Laboratory of Molecular Signaling, NIAAA, NIH, Rockville, Maryland
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38
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Das M, Tang X, Mohapatra SS, Mohapatra S. Vision impairment after traumatic brain injury: present knowledge and future directions. Rev Neurosci 2019; 30:305-315. [PMID: 30226209 DOI: 10.1515/revneuro-2018-0015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 06/15/2018] [Indexed: 01/23/2023]
Abstract
Traumatic brain injury (TBI) is a major cause of mortality and morbidity in the USA as well as in the world. As a result of TBI, the visual system is also affected often causing complete or partial visual loss, which in turn affects the quality of life. It may also lead to ocular motor dysfunction, defective accommodation, and impaired visual perception. As a part of the therapeutic strategy, early rehabilitative optometric intervention is important. Orthoptic therapy, medication, stem cell therapy, motor and attention trainings are the available treatment options. Gene therapy is one of the most promising emerging strategies. Use of state-of-the-art nanomedicine approaches to deliver drug(s) and/or gene(s) might enhance the therapeutic efficacy of the present and future modalities. More research is needed in these fields to improve the outcome of this debilitating condition. This review focuses on different visual pathologies caused by TBI, advances in pre-clinical and clinical research, and available treatment options.
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Affiliation(s)
- Mahasweta Das
- James A. Haley Veterans Administration Hospital, Tampa, FL 33612, USA.,Department of Molecular Medicine, University of South Florida College of Medicine, Tampa, FL 33612, USA
| | - Xiaolan Tang
- James A. Haley Veterans Administration Hospital, Tampa, FL 33612, USA.,Department of Molecular Medicine, University of South Florida College of Medicine, Tampa, FL 33612, USA
| | - Shyam S Mohapatra
- James A. Haley Veterans Administration Hospital, Tampa, FL 33612, USA.,Department of Internal Medicine, University of South Florida College of Medicine, Tampa, FL 33612, USA
| | - Subhra Mohapatra
- James A. Haley Veterans Administration Hospital, Tampa, FL 33612, USA.,Department of Molecular Medicine, University of South Florida College of Medicine, Tampa, FL 33612, USA
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39
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Chintalapudi SR, Wang X, Wang X, Shi Y, Kocak M, Palamoor M, Davis RN, Hollingsworth TJ, Jablonski MM. NA3 glycan: a potential therapy for retinal pigment epithelial deficiency. FEBS J 2019; 286:4876-4888. [PMID: 31322324 DOI: 10.1111/febs.15006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 05/07/2019] [Accepted: 07/16/2019] [Indexed: 12/01/2022]
Abstract
Atrophic age-related macular degeneration (AMD) is the most common type of AMD, yet there is no United States Food and Drug Administration (FDA)-approved therapy. This disease is characterized by retinal pigment epithelial (RPE) insufficiency, primarily in the macula, which affects the structure and physiology of photoreceptors and ultimately, visual function. In this study, we evaluated the protective effects of a naturally derived small molecule glycan therapeutic-asialo-, tri-antennary complex-type N-glycan (NA3)-in two distinct preclinical models of atrophic AMD. In RPE-deprived Xenopus laevis tadpole eyes, NA3 supported normal retinal ultrastructure. In RCS rats, NA3 supported fully functioning visual integrity. Furthermore, structural analyses revealed that NA3 prevented photoreceptor outer segment degeneration, pyknosis of the outer nuclear layer, and reactive gliosis of Müller cells (MCs). It also promoted maturation of adherens junctions between MC and photoreceptors. Our results demonstrate the neuroprotective effects of a naturally derived small molecular glycan therapeutic-NA3-in two unique preclinical models with RPE insufficiency. These data suggest that NA3 glycan therapy may provide a new therapeutic avenue in the prevention and/or treatment of retinal diseases such as atrophic AMD.
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Affiliation(s)
- Sumana R Chintalapudi
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - XiangDi Wang
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - XiaoFei Wang
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Yunfeng Shi
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Mehmet Kocak
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Mallika Palamoor
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Raven N Davis
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - T J Hollingsworth
- Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Monica M Jablonski
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
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40
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Li Y, Yang Z, Liu B, Valdez C, Chavko M, Cancio LC. Low-Level Primary Blast Induces Neuroinflammation and Neurodegeneration in Rats. Mil Med 2019; 184:265-272. [PMID: 30901455 DOI: 10.1093/milmed/usy330] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/10/2018] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVE Mild blast traumatic brain injury is commonly prevalent in modern combat casualty care and has been associated with the development of neurodegenerative conditions. However, whether primary lower level blast overpressure (LBOP) causes neurodegeneration and neuroinflammation remains largely unknown. The aim of our present study was to determine whether LBOP can cause neuroinflammation and neurodegeneration. METHODS Anesthetized rats were randomly assigned to LBOP group (70 kPa, n = 5) or sham group (without blast, n = 5). Histopathological and cytokine changes in brain tissue at 5 days post-injury were evaluated by hematoxylin-eosin staining and Bioplex assay, respectively. RESULTS Histopathological assessment revealed neuronal degeneration and increased density of inflammatory cells in frontal and parietal cortex, hippocampus and thalamus in rats exposed to LBOP. LBOP exposure significantly elevated levels of pro-inflammatory cytokines (EPO, IL-1β, IL-6, IL-12, IL-18, and TNF-α) and chemokines (GRO and RANTES) as well as of an anti-inflammatory cytokine (IL-13) in the frontal cortex. CONCLUSIONS This study reveals a role of neuroinflammation in neurodegeneration after mild blast traumatic brain injury. Therapies that target this process might in warfighters might function either by attenuating the development of post-traumatic stress disorder, chronic traumatic encephalopathy and Alzheimer's disease, or by slowing their progression.
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Affiliation(s)
- Yansong Li
- US Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, TX
| | - Zhangsheng Yang
- US Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, TX
| | - Bin Liu
- US Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, TX
| | - Celina Valdez
- US Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, TX
| | - Mikulas Chavko
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD
| | - Leopoldo C Cancio
- US Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, TX
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41
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Pro-Inflammatory Activation of A New Immortalized Human Microglia Cell Line. Brain Sci 2019; 9:brainsci9050111. [PMID: 31096716 PMCID: PMC6562668 DOI: 10.3390/brainsci9050111] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/06/2019] [Accepted: 05/13/2019] [Indexed: 11/25/2022] Open
Abstract
The characterization of human microglia has been hampered by poor availability of human cell sources. However, microglia is involved in the physiopathology of multiple sclerosis, Alzheimer’s disease, Parkinson’s disease, HIV dementia, retinal degenerative diseases, cancer, and many other conditions. Therefore, there is an important need to have experimental paradigms of human microglia characterized and usable to study the role of microglia in the different pathologies in which it is involved. In the present work, we carried out an extensive characterization of Immortalized Human Microglia—SV40 cell line (IMhu), marketed by Applied Biological Material. The functional response of IMhu to a large variety of stimuli was studied. In particular, we investigated morphology, mortality, and changes in the production of different cytokines and chemokines, both under basal conditions and after stimulation. Moreover, western blotting analysis was conducted on phospho-mTOR (Ser 2448) and downstream parameters, p-P70S6K and 4EBP1, in order to understand if IMhu can be used for evaluations of mTOR pathway. In conclusion, IMhu cells proved to be a useful experimental model to investigate the physiopathology of inflammatory disease that involved microglia cells, including pathological conditions that involved the mTOR pathway.
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42
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Guley NM, Del Mar NA, Ragsdale T, Li C, Perry AM, Moore BM, Honig MG, Reiner A. Amelioration of visual deficits and visual system pathology after mild TBI with the cannabinoid type-2 receptor inverse agonist SMM-189. Exp Eye Res 2019; 182:109-124. [PMID: 30922891 DOI: 10.1016/j.exer.2019.03.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/11/2019] [Accepted: 03/19/2019] [Indexed: 12/20/2022]
Abstract
Mild TBI is often accompanied by visual system dysfunction and injury, which is at least partly caused by microglial neuroinflammatory processes initiated by the injury. Using our focal cranial blast mouse model of closed-skull mild TBI, we evaluated the ability of the cannabinoid type-2 (CB2) receptor inverse agonist SMM-189, which biases microglia from the harmful M1 state to the beneficial M2 state, to mitigate visual system dysfunction and injury after TBI. Male C57BL/6 or Thy1-EYFP reporter mice received a closed-head blast of either 0-psi (sham) or 50-psi to the left side of the cranium. Blast mice received vehicle or 6 mg/kg SMM-189 daily beginning 2 h after blast. Sham mice received vehicle. In some mice, retina and optic nerve/tract were assessed morphologically at 3-7 days after blast, while other mice were assessed functionally by Optomotry 30 days after blast and morphologically at ≥30 days after blast. Mice sacrificed at 3-7 days were treated daily until sacrificed, while those assessed ≥30 days after blast were treated daily for 2 weeks post blast. Axon damage was evident in the left optic nerve and its continuation as the right optic tract at 3 days post blast in vehicle-treated blast mice in the form of swollen axon bulbs, and was accompanied by a significant increase in the abundance of microglia. Testing at 30 days post blast revealed that the contrast sensitivity function was significantly reduced in both eyes in vehicle-treated blast mice compared to vehicle-treated sham blast mice, and axon counts at ≥30 days after blast revealed a ∼10% loss in left optic nerve in vehicle-treated blast mice. Left optic nerve axon loss was highly correlated with the left eye deficit in contrast sensitivity. Immunolabeling at 30 days post blast showed a significant increase in the abundance of microglia in the retinas of both eyes and in GFAP + Müller cell processes traversing the inner plexiform layer in the left eye of vehicle-treated blast mice. SMM-189 treatment reduced axon injury and microglial abundance at 3 days, and mitigated axon loss, contrast sensitivity deficits, microglial abundance, and Müller cell GFAP upregulation at ≥30 days after blast injury. Analysis of right optic tract microglia at 3 days post blast for M1 versus M2 markers revealed that SMM-189 biased microglia toward the M2 state, with this action of SMM-189 being linked to reduced axonal injury. Taken together, our results show that focal left side cranial blast resulted in impaired contrast sensitivity and retinal pathology bilaterally and optic nerve loss ipsilaterally. The novel cannabinoid drug SMM-189 significantly mitigated the functional deficit and the associated pathologies. Our findings suggest the value of combatting visual system injury after TBI by using CB2 inverse agonists such as SMM-189, which appear to target microglia and bias them away from the pro-inflammatory M1 state, toward the protective M2 state.
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Affiliation(s)
- Natalie M Guley
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Nobel A Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Tyler Ragsdale
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Chunyan Li
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Aaron M Perry
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Bob M Moore
- Dept. of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Marcia G Honig
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States; Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, TN 38163, United States.
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43
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Younger D, Murugan M, Rama Rao KV, Wu LJ, Chandra N. Microglia Receptors in Animal Models of Traumatic Brain Injury. Mol Neurobiol 2018; 56:5202-5228. [DOI: 10.1007/s12035-018-1428-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 11/13/2018] [Indexed: 02/07/2023]
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44
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Madathil SK, Wilfred BS, Urankar SE, Yang W, Leung LY, Gilsdorf JS, Shear DA. Early Microglial Activation Following Closed-Head Concussive Injury Is Dominated by Pro-Inflammatory M-1 Type. Front Neurol 2018; 9:964. [PMID: 30498469 PMCID: PMC6249371 DOI: 10.3389/fneur.2018.00964] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/26/2018] [Indexed: 12/17/2022] Open
Abstract
Microglial activation is a pathological hallmark of traumatic brain injury (TBI). Following brain injury, activated microglia/macrophages adopt different phenotypes, generally categorized as M-1, or classically activated, and M-2, or alternatively activated. While the M-1, or pro-inflammatory phenotype is detrimental to recovery, M-2, or the anti-inflammatory phenotype, aids in brain repair. Recent findings also suggest the existence of mixed phenotype following brain injury, where activated microglia simultaneously express both M-1 and M-2 markers. The present study sought to determine microglial activation states at early time points (6-72 h) following single or repeated concussive injury in rats. Closed-head concussive injury was modeled in rats using projectile concussive impact injury, with either single or repeated impacts (4 impacts, 1 h apart). Brain samples were examined using immunohistochemical staining, inflammatory gene profiling and real-time polymerase chain reaction analyses to detect concussive injury induced changes in microglial activation and phenotype in cortex and hippocampal regions. Our findings demonstrate robust microglial activation following concussive brain injury. Moreover, we show that multiple concussions induced a unique rod-shaped microglial morphology that was also observed in other diffuse brain injury models. Histological studies revealed a predominance of MHC-II positive M-1 phenotype in the post-concussive microglial milieu following multiple impacts. Although there was simultaneous expression of M-1 and M-2 markers, gene expression results indicate a clear dominance in M-1 pro-inflammatory markers following both single and repeated concussions. While the increase in M-1 markers quickly resolved after a single concussion, they persisted following repeated concussions, indicating a pro-inflammatory environment induced by multiple concussions that may delay recovery and contribute to long-lasting consequences of concussion.
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Affiliation(s)
- Sindhu K Madathil
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Bernard S Wilfred
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Sarah E Urankar
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Weihong Yang
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Lai Yee Leung
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States.,Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Janice S Gilsdorf
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Deborah A Shear
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
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45
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Dello Russo C, Cappoli N, Coletta I, Mezzogori D, Paciello F, Pozzoli G, Navarra P, Battaglia A. The human microglial HMC3 cell line: where do we stand? A systematic literature review. J Neuroinflammation 2018; 15:259. [PMID: 30200996 PMCID: PMC6131758 DOI: 10.1186/s12974-018-1288-0] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/21/2018] [Indexed: 02/08/2023] Open
Abstract
Microglia, unique myeloid cells residing in the brain parenchyma, represent the first line of immune defense within the central nervous system. In addition to their immune functions, microglial cells play an important role in other cerebral processes, including the regulation of synaptic architecture and neurogenesis. Chronic microglial activation is regarded as detrimental, and it is considered a pathogenic mechanism common to several neurological disorders. Microglial activation and function have been extensively studied in rodent experimental models, whereas the characterization of human cells has been limited due to the restricted availability of primary sources of human microglia. To overcome this problem, human immortalized microglial cell lines have been developed. The human microglial clone 3 cell line, HMC3, was established in 1995, through SV40-dependent immortalization of human embryonic microglial cells. It has been recently authenticated by the American Type Culture Collection (ATCC®) and distributed under the name of HMC3 (ATCC®CRL-3304). The HMC3 cells have been used in six research studies, two of which also indicated by ATCC® as reference articles. However, a more accurate literature revision suggests that clone 3 was initially distributed under the name of CHME3. In this regard, several studies have been published, thus contributing to a more extensive characterization of this cell line. Remarkably, the same cell line has been used in different laboratories with other denominations, i.e., CHME-5 cells and C13-NJ cells. In view of the fact that "being now authenticated by ATCC®" may imply a wider distribution of the cells, we aimed at reviewing data obtained with the human microglia cell line clone 3, making the readers aware of this complicated nomenclature. In addition, we also included original data, generated in our laboratory with the HMC3 (ATCC®CRL-3304) cells, providing information on the current state of the culture together with supplementary details on the culturing procedures to obtain and maintain viable cells.
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Affiliation(s)
- Cinzia Dello Russo
- Institute of Pharmacology, Università Cattolica del S. Cuore, L.go F Vito 1, 00168, Rome, Italy. .,Pharmacology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.
| | - Natalia Cappoli
- Institute of Pharmacology, Università Cattolica del S. Cuore, L.go F Vito 1, 00168, Rome, Italy
| | - Isabella Coletta
- Angelini RR&D (Research, Regulatory & Development) - Angelini S.p.A., Rome, Italy
| | - Daniele Mezzogori
- Institute of Human Physiology, Università Cattolica del S. Cuore, Rome, Italy
| | - Fabiola Paciello
- Institute of Otolaryngology, Università Cattolica del S. Cuore, Rome, Italy
| | - Giacomo Pozzoli
- Institute of Pharmacology, Università Cattolica del S. Cuore, L.go F Vito 1, 00168, Rome, Italy.,Pharmacology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Pierluigi Navarra
- Institute of Pharmacology, Università Cattolica del S. Cuore, L.go F Vito 1, 00168, Rome, Italy.,Pharmacology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Alessandra Battaglia
- Immunology Laboratory, Department of Oncological Gynecology, Università Cattolica del S. Cuore, Rome, Italy
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46
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Franks LN, Ford BM, Fujiwara T, Zhao H, Prather PL. The tamoxifen derivative ridaifen-B is a high affinity selective CB 2 receptor inverse agonist exhibiting anti-inflammatory and anti-osteoclastogenic effects. Toxicol Appl Pharmacol 2018; 353:31-42. [PMID: 29906493 PMCID: PMC6487498 DOI: 10.1016/j.taap.2018.06.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 05/25/2018] [Accepted: 06/11/2018] [Indexed: 12/15/2022]
Abstract
Selective estrogen receptor modulators (SERMs) target estrogen receptors (ERs) to treat breast cancer and osteoporosis. Several SERMs exhibit anti-cancer activity not related to ERs. To discover novel anti-cancer drugs acting via ER-independent mechanisms, derivatives of the SERM tamoxifen, known as the "ridaifen" compounds, have been developed that exhibit reduced or no ER affinity, while maintaining cytotoxicity. Tamoxifen and other SERMs bind to cannabinoid receptors with moderate affinity. Therefore, ER-independent effects of SERMs might be mediated via cannabinoid receptors. This study determined whether RID-B, a first generation ridaifen compound, exhibits affinity and/or activity at CB1 and/or CB2 cannabinoid receptors. RID-B binds with high affinity (Ki = 43.7 nM) and 17-fold selectivity to CB2 over CB1 receptors. RID-B acts as an inverse agonist at CB2 receptors, modulating G-protein and adenylyl cyclase activity with potency values predicted by CB2 affinity. Characteristic of an antagonist, RID-B co-incubation produces a parallel-rightward shift in the concentration-effect curve of CB2 agonist WIN-55,212-2 to inhibit adenylyl cyclase activity. CB2 inverse agonists are reported to exhibit anti-inflammatory and anti-ostoeclastogenic effects. In LPS-activated macrophages, RID-B exhibits anti-inflammatory effects by reducing levels of nitric oxide (NO), IL-6 and IL-1α, but not TNFα. Only reduction of NO concentration by RID-B is mediated by cannabinoid receptors. RID-B also exhibits pronounced anti-osteoclastogenic effects, reducing the number of osteoclasts differentiating from primary bone marrow macrophages in a cannabinoid receptor-dependent manner. In summary, the tamoxifen derivative RID-B, developed with reduced affinity for ERs, is a high affinity selective CB2 inverse agonist with anti-inflammatory and anti-osteoclastogenic properties.
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MESH Headings
- Adenylyl Cyclase Inhibitors/pharmacology
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Benzoxazines/pharmacology
- Binding, Competitive/drug effects
- Bone Marrow Cells/drug effects
- CHO Cells
- Cell Differentiation/drug effects
- Cricetinae
- Cricetulus
- Drug Inverse Agonism
- Mice
- Mice, Inbred C57BL
- Morpholines/pharmacology
- Naphthalenes/pharmacology
- Osteoclasts/drug effects
- Pyrrolidines/metabolism
- Pyrrolidines/pharmacology
- Receptor, Cannabinoid, CB1/drug effects
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/metabolism
- Selective Estrogen Receptor Modulators/metabolism
- Selective Estrogen Receptor Modulators/pharmacology
- Tamoxifen/analogs & derivatives
- Tamoxifen/metabolism
- Tamoxifen/pharmacology
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Affiliation(s)
- Lirit N Franks
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Benjamin M Ford
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Toshifumi Fujiwara
- Department of Internal Medicine, Endocrinology Division, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Haibo Zhao
- Department of Internal Medicine, Endocrinology Division, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
| | - Paul L Prather
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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47
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Semple BD, Zamani A, Rayner G, Shultz SR, Jones NC. Affective, neurocognitive and psychosocial disorders associated with traumatic brain injury and post-traumatic epilepsy. Neurobiol Dis 2018; 123:27-41. [PMID: 30059725 DOI: 10.1016/j.nbd.2018.07.018] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 07/08/2018] [Accepted: 07/16/2018] [Indexed: 12/13/2022] Open
Abstract
Survivors of traumatic brain injury (TBI) often develop chronic neurological, neurocognitive, psychological, and psychosocial deficits that can have a profound impact on an individual's wellbeing and quality of life. TBI is also a common cause of acquired epilepsy, which is itself associated with significant behavioral morbidity. This review considers the clinical and preclinical evidence that post-traumatic epilepsy (PTE) acts as a 'second-hit' insult to worsen chronic behavioral outcomes for brain-injured patients, across the domains of emotional, cognitive, and psychosocial functioning. Surprisingly, few well-designed studies have specifically examined the relationship between seizures and behavioral outcomes after TBI. The complex mechanisms underlying these comorbidities remain incompletely understood, although many of the biological processes that precipitate seizure occurrence and epileptogenesis may also contribute to the development of chronic behavioral deficits. Further, the relationship between PTE and behavioral dysfunction is increasingly recognized to be a bidirectional one, whereby premorbid conditions are a risk factor for PTE. Clinical studies in this arena are often challenged by the confounding effects of anti-seizure medications, while preclinical studies have rarely examined an adequately extended time course to fully capture the time course of epilepsy development after a TBI. To drive the field forward towards improved treatment strategies, it is imperative that both seizures and neurobehavioral outcomes are assessed in parallel after TBI, both in patient populations and preclinical models.
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Affiliation(s)
- Bridgette D Semple
- Department of Neuroscience, Monash University, 99 Commercial Road, Melbourne, VIC, Australia; Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, VIC, Australia.
| | - Akram Zamani
- Department of Neuroscience, Monash University, 99 Commercial Road, Melbourne, VIC, Australia.
| | - Genevieve Rayner
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre (Austin Campus), Heidelberg, VIC, Australia; Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, Australia; Comprehensive Epilepsy Program, Alfred Health, Australia.
| | - Sandy R Shultz
- Department of Neuroscience, Monash University, 99 Commercial Road, Melbourne, VIC, Australia; Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, VIC, Australia.
| | - Nigel C Jones
- Department of Neuroscience, Monash University, 99 Commercial Road, Melbourne, VIC, Australia; Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, VIC, Australia.
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48
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Allen RS, Motz CT, Feola A, Chesler KC, Haider R, Ramachandra Rao S, Skelton LA, Fliesler SJ, Pardue MT. Long-Term Functional and Structural Consequences of Primary Blast Overpressure to the Eye. J Neurotrauma 2018; 35:2104-2116. [PMID: 29648979 DOI: 10.1089/neu.2017.5394] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Acoustic blast overpressure (ABO) injury in military personnel and civilians is often accompanied by delayed visual deficits. However, most animal model studies dealing with blast-induced visual defects have focused on short-term (≤1 month) changes. Here, we evaluated long-term (≤8 months) retinal structure and function deficits in rats with ABO injury. Adult male Long-Evans rats were subjected to ABO from a single blast (approximately 190 dB SPL, ∼63 kPa, @80 psi), generated by a shock tube device. Retinal function (electroretinography; ERG), visual function (optomotor response), retinal thickness (spectral domain-optical coherence tomography; SD-OCT), and spatial cognition/exploratory motor behavior (Y-maze) were measured at 2, 4, 6, and 8 months post-blast. Immunohistochemical analysis of glial fibrillary acidic protein (GFAP) in retinal sections was performed at 8 months post-blast. Electroretinogram a- and b-waves, oscillatory potentials, and flicker responses showed greater amplitudes with delayed implicit times in both eyes of blast-exposed animals, relative to controls. Contrast sensitivity (CS) was reduced in both eyes of blast-exposed animals, whereas spatial frequency (SF) was decreased only in ipsilateral eyes, relative to controls. Total retinal thickness was greater in both eyes of blast-exposed animals, relative to controls, due to increased thickness of several retinal layers. Age, but not blast exposure, altered Y-maze outcomes. GFAP was greatly increased in blast-exposed retinas. ABO exposure resulted in visual and retinal changes that persisted up to 8 months post-blast, mimicking some of the visual deficits observed in human blast-exposed patients, thereby making this a useful model to study mechanisms of injury and potential treatments.
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Affiliation(s)
- Rachael S Allen
- 1 Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center , Atlanta, Georgia .,2 Biomedical Engineering, Georgia Institute of Technology , Atlanta, Georgia
| | - Cara T Motz
- 1 Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center , Atlanta, Georgia
| | - Andrew Feola
- 1 Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center , Atlanta, Georgia .,2 Biomedical Engineering, Georgia Institute of Technology , Atlanta, Georgia
| | - Kyle C Chesler
- 2 Biomedical Engineering, Georgia Institute of Technology , Atlanta, Georgia
| | - Raza Haider
- 1 Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center , Atlanta, Georgia
| | - Sriganesh Ramachandra Rao
- 3 Ophthalmology, Biochemistry, and Neuroscience Program, SUNY-University at Buffalo , Buffalo, New York
| | - Lara A Skelton
- 4 Research Service, VA Western NY Healthcare System , Buffalo, New York
| | - Steven J Fliesler
- 3 Ophthalmology, Biochemistry, and Neuroscience Program, SUNY-University at Buffalo , Buffalo, New York.,4 Research Service, VA Western NY Healthcare System , Buffalo, New York
| | - Machelle T Pardue
- 1 Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center , Atlanta, Georgia .,2 Biomedical Engineering, Georgia Institute of Technology , Atlanta, Georgia
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49
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Evanson NK, Guilhaume-Correa F, Herman JP, Goodman MD. Optic tract injury after closed head traumatic brain injury in mice: A model of indirect traumatic optic neuropathy. PLoS One 2018; 13:e0197346. [PMID: 29746557 PMCID: PMC5944994 DOI: 10.1371/journal.pone.0197346] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 05/01/2018] [Indexed: 12/14/2022] Open
Abstract
Adult male C57BL/6J mice have previously been reported to have motor and memory deficits after experimental closed head traumatic brain injury (TBI), without associated gross pathologic damage or neuroimaging changes detectable by magnetic resonance imaging or diffusion tensor imaging protocols. The presence of neurologic deficits, however, suggests neural damage or dysfunction in these animals. Accordingly, we undertook a histologic analysis of mice after TBI. Gross pathology and histologic analysis using Nissl stain and NeuN immunohistochemistry demonstrated no obvious tissue damage or neuron loss. However, Luxol Fast Blue stain revealed myelin injury in the optic tract, while Fluoro Jade B and silver degeneration staining revealed evidence of axonal neurodegeneration in the optic tract as well as the lateral geniculate nucleus of the thalamus and superior colliculus (detectable at 7 days, but not 24 hours, after injury). Fluoro Jade B staining was not detectable in other white matter tracts, brain regions or in cell somata. In addition, there was increased GFAP staining in these optic tract, lateral geniculate, and superior colliculus 7 days post-injury, and morphologic changes in optic tract microglia that were detectable 24 hours after injury but were more prominent 7 days post-injury. Interestingly, there were no findings of degeneration or gliosis in the suprachiasmatic nucleus, which is also heavily innervated by the optic tract. Using micro-computed tomography imaging, we also found that the optic canal appears to decrease in diameter with a dorsal-ventral load on the skull, which suggests that the optic canal may be the site of injury. These results suggest that there is axonal degeneration in the optic tract and a subset of directly innervated areas, with associated neuroinflammation and astrocytosis, which develop within 7 days of injury, and also suggest that this weight drop injury may be a model for studying indirect traumatic optic neuropathy.
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Affiliation(s)
- Nathan K. Evanson
- Division of Pediatric Rehabilitation Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, United States of America
- * E-mail:
| | - Fernanda Guilhaume-Correa
- Division of Pediatric Rehabilitation Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - James P. Herman
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Michael D. Goodman
- Department of Surgery, University of Cincinnati, Cincinnati, Ohio, United States of America
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50
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Madathil SK, Wilfred BS, Urankar SE, Yang W, Leung LY, Gilsdorf JS, Shear DA. Early Microglial Activation Following Closed-Head Concussive Injury Is Dominated by Pro-Inflammatory M-1 Type. Front Neurol 2018. [PMID: 30498469 DOI: 10.3389/fneur.2018.00964/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023] Open
Abstract
Microglial activation is a pathological hallmark of traumatic brain injury (TBI). Following brain injury, activated microglia/macrophages adopt different phenotypes, generally categorized as M-1, or classically activated, and M-2, or alternatively activated. While the M-1, or pro-inflammatory phenotype is detrimental to recovery, M-2, or the anti-inflammatory phenotype, aids in brain repair. Recent findings also suggest the existence of mixed phenotype following brain injury, where activated microglia simultaneously express both M-1 and M-2 markers. The present study sought to determine microglial activation states at early time points (6-72 h) following single or repeated concussive injury in rats. Closed-head concussive injury was modeled in rats using projectile concussive impact injury, with either single or repeated impacts (4 impacts, 1 h apart). Brain samples were examined using immunohistochemical staining, inflammatory gene profiling and real-time polymerase chain reaction analyses to detect concussive injury induced changes in microglial activation and phenotype in cortex and hippocampal regions. Our findings demonstrate robust microglial activation following concussive brain injury. Moreover, we show that multiple concussions induced a unique rod-shaped microglial morphology that was also observed in other diffuse brain injury models. Histological studies revealed a predominance of MHC-II positive M-1 phenotype in the post-concussive microglial milieu following multiple impacts. Although there was simultaneous expression of M-1 and M-2 markers, gene expression results indicate a clear dominance in M-1 pro-inflammatory markers following both single and repeated concussions. While the increase in M-1 markers quickly resolved after a single concussion, they persisted following repeated concussions, indicating a pro-inflammatory environment induced by multiple concussions that may delay recovery and contribute to long-lasting consequences of concussion.
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Affiliation(s)
- Sindhu K Madathil
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Bernard S Wilfred
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Sarah E Urankar
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Weihong Yang
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Lai Yee Leung
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States.,Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Janice S Gilsdorf
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Deborah A Shear
- Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
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