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Trueblood CT, Singh A, Cusimano MA, Hou S. Autonomic Dysreflexia in Spinal Cord Injury: Mechanisms and Prospective Therapeutic Targets. Neuroscientist 2024; 30:597-611. [PMID: 38084412 PMCID: PMC11166887 DOI: 10.1177/10738584231217455] [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] [Indexed: 06/13/2024]
Abstract
High-level spinal cord injury (SCI) often results in cardiovascular dysfunction, especially the development of autonomic dysreflexia. This disorder, characterized as an episode of hypertension accompanied by bradycardia in response to visceral or somatic stimuli, causes substantial discomfort and potentially life-threatening symptoms. The neural mechanisms underlying this dysautonomia include a loss of supraspinal control to spinal sympathetic neurons, maladaptive plasticity of sensory inputs and propriospinal interneurons, and excessive discharge of sympathetic preganglionic neurons. While neural control of cardiovascular function is largely disrupted after SCI, the renin-angiotensin system (RAS), which mediates blood pressure through hormonal mechanisms, is up-regulated after injury. Whether the RAS engages in autonomic dysreflexia, however, is still controversial. Regarding therapeutics, transplantation of embryonic presympathetic neurons, collected from the brainstem or more specific raphe regions, into the injured spinal cord may reestablish supraspinal regulation of sympathetic activity for cardiovascular improvement. This treatment reduces the occurrence of spontaneous autonomic dysreflexia and the severity of artificially triggered dysreflexic responses in rodent SCI models. Though transplanting early-stage neurons improves neural regulation of blood pressure, hormonal regulation remains high and baroreflex dysfunction persists. Therefore, cell transplantation combined with selected RAS inhibition may enhance neuroendocrine homeostasis for cardiovascular recovery after SCI.
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Affiliation(s)
- Cameron T. Trueblood
- Marion Murray Spinal Cord Research Center, Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Anurag Singh
- Marion Murray Spinal Cord Research Center, Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Marissa A. Cusimano
- Marion Murray Spinal Cord Research Center, Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Shaoping Hou
- Marion Murray Spinal Cord Research Center, Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
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Martynyuk T, Ricard J, Bracchi-Ricard V, Price S, McGrath J, Dougherty K, Tom V, Bethea JR. Mitigating sTNF/TNFR1 activation on VGluT2+ spinal cord interneurons improves immune function after mid-thoracic spinal cord injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.09.602690. [PMID: 39026822 PMCID: PMC11257617 DOI: 10.1101/2024.07.09.602690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Spinal cord injury (SCI) is a devastating condition with 250,000 to 500,000 new cases globally each year. Respiratory infections, e.g., pneumonia and influenza are the leading cause of death after SCI. Unfortunately, there is a poor understanding of how altered neuro-immune communication impacts an individual's outcome to infection. In humans and rodents, SCI leads to maladaptive changes in the spinal-sympathetic reflex (SSR) circuit which is crucial to sympathetic function. The cause of the impaired immune function may be related to harmful neuroinflammation which is detrimental to homeostatic neuronal function, aberrant plasticity, and hyperexcitable circuits. Soluble tumor necrosis factor (sTNF) is a pro-inflammatory cytokine that is elevated in the CNS after SCI and remains elevated for several months after injury. By pharmacologically attenuating sTNF in the CNS after SCI we were able to demonstrate improved immune function. Furthermore, when we investigated the specific cellular population which may be involved in altered neuro-immune communication we reported that excessive TNFR1 activity on excitatory INs promotes immune dysfunction. Furthermore, this observation is NF-κB dependent in VGluT2+ INs. Our data is the first report of a target within the CNS, TNFR1, that contributes to SCI-induced immune dysfunction after T9-SCI and is a potential avenue for future therapeutics.
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Affiliation(s)
| | - Jerome Ricard
- Drexel University, Department of Biology, Philadelphia, PA
| | | | - Samuel Price
- Drexel University, Department of Biology, Philadelphia, PA
| | - Jenna McGrath
- Drexel University, Department of Neurobiology and Anatomy, Philadelphia, PA
| | - Kimberly Dougherty
- Drexel University, Department of Neurobiology and Anatomy, Philadelphia, PA
| | - Veronica Tom
- Drexel University, Department of Neurobiology and Anatomy, Philadelphia, PA
| | - John R. Bethea
- Drexel University, Department of Biology, Philadelphia, PA
- George Washington University, Department of Anatomy and Cell Biology, Washington D.C
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3
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Brennan FH, Swarts EA, Kigerl KA, Mifflin KA, Guan Z, Noble BT, Wang Y, Witcher KG, Godbout JP, Popovich PG. Microglia promote maladaptive plasticity in autonomic circuitry after spinal cord injury in mice. Sci Transl Med 2024; 16:eadi3259. [PMID: 38865485 DOI: 10.1126/scitranslmed.adi3259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 05/16/2024] [Indexed: 06/14/2024]
Abstract
Robust structural remodeling and synaptic plasticity occurs within spinal autonomic circuitry after severe high-level spinal cord injury (SCI). As a result, normally innocuous visceral or somatic stimuli elicit uncontrolled activation of spinal sympathetic reflexes that contribute to systemic disease and organ-specific pathology. How hyperexcitable sympathetic circuitry forms is unknown, but local cues from neighboring glia likely help mold these maladaptive neuronal networks. Here, we used a mouse model of SCI to show that microglia surrounded active glutamatergic interneurons and subsequently coordinated multi-segmental excitatory synaptogenesis and expansion of sympathetic networks that control immune, neuroendocrine, and cardiovascular functions. Depleting microglia during critical periods of circuit remodeling after SCI prevented maladaptive synaptic and structural plasticity in autonomic networks, decreased the frequency and severity of autonomic dysreflexia, and prevented SCI-induced immunosuppression. Forced turnover of microglia in microglia-depleted mice restored structural and functional indices of pathological dysautonomia, providing further evidence that microglia are key effectors of autonomic plasticity. Additional data show that microglia-dependent autonomic plasticity required expression of triggering receptor expressed on myeloid cells 2 (Trem2) and α2δ-1-dependent synaptogenesis. These data suggest that microglia are primary effectors of autonomic neuroplasticity and dysautonomia after SCI in mice. Manipulating microglia may be a strategy to limit autonomic complications after SCI or other forms of neurologic disease.
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Affiliation(s)
- Faith H Brennan
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Department of Biomedical and Molecular Sciences and Center for Neuroscience Studies, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Emily A Swarts
- Department of Biomedical and Molecular Sciences and Center for Neuroscience Studies, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Kristina A Kigerl
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Katherine A Mifflin
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Zhen Guan
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Benjamin T Noble
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Yan Wang
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Kristina G Witcher
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Institute for Behavioral Medicine Research, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Jonathan P Godbout
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Institute for Behavioral Medicine Research, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Phillip G Popovich
- Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Belford Center for Spinal Cord Injury, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
- Institute for Behavioral Medicine Research, Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
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4
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Moura MM, Monteiro A, Salgado AJ, Silva NA, Monteiro S. Disrupted autonomic pathways in spinal cord injury: Implications for the immune regulation. Neurobiol Dis 2024; 195:106500. [PMID: 38614275 DOI: 10.1016/j.nbd.2024.106500] [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: 11/21/2023] [Revised: 03/25/2024] [Accepted: 04/04/2024] [Indexed: 04/15/2024] Open
Abstract
Spinal Cord Injury (SCI) disrupts critical autonomic pathways responsible for the regulation of the immune function. Consequently, individuals with SCI often exhibit a spectrum of immune dysfunctions ranging from the development of damaging pro-inflammatory responses to severe immunosuppression. Thus, it is imperative to gain a more comprehensive understanding of the extent and mechanisms through which SCI-induced autonomic dysfunction influences the immune response. In this review, we provide an overview of the anatomical organization and physiology of the autonomic nervous system (ANS), elucidating how SCI impacts its function, with a particular focus on lymphoid organs and immune activity. We highlight recent advances in understanding how intraspinal plasticity that follows SCI may contribute to aberrant autonomic activity in lymphoid organs. Additionally, we discuss how sympathetic mediators released by these neuron terminals affect immune cell function. Finally, we discuss emerging innovative technologies and potential clinical interventions targeting the ANS as a strategy to restore the normal regulation of the immune response in individuals with SCI.
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Affiliation(s)
- Maria M Moura
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - Andreia Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - António J Salgado
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - Nuno A Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - Susana Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal.
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5
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Yang P, Bian ZQ, Song ZB, Yang CY, Wang L, Yao ZX. Dominant mechanism in spinal cord injury-induced immunodeficiency syndrome (SCI-IDS): sympathetic hyperreflexia. Rev Neurosci 2024; 35:259-269. [PMID: 37889575 DOI: 10.1515/revneuro-2023-0090] [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: 08/16/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023]
Abstract
Clinical studies have shown that individuals with spinal cord injury (SCI) are particularly susceptible to infectious diseases, resulting in a syndrome called SCI-induced immunodeficiency syndrome (SCI-IDS), which is the leading cause of death after SCI. It is believed that SCI-IDS is associated with exaggerated activation of sympathetic preganglionic neurons (SPNs). After SCI, disruption of bulbospinal projections from the medulla oblongata C1 neurons to the SPNs results in the loss of sympathetic inhibitory modulation from the brain and brainstem and the occurrence of abnormally high levels of spinal sympathetic reflexes (SSR), named sympathetic hyperreflexia. As the post-injury survival time lengthens, mass recruitment and anomalous sprouting of excitatory interneurons within the spinal cord result in increased SSR excitability, resulting in an excess sympathetic output that disrupts the immune response. Therefore, we first analyze the structural underpinnings of the spinal cord-sympathetic nervous system-immune system after SCI, then demonstrate the progress in highlighting mechanisms of SCI-IDS focusing on norepinephrine (NE)/Beta 2-adrenergic receptor (β2-AR) signal pathways, and summarize recent preclinical studies examining potential means such as regulating SSR and inhibiting β2-AR signal pathways to improve immune function after SCI. Finally, we present research perspectives such as to promote the effective regeneration of C1 neurons to rebuild the connection of C1 neurons with SPNs, to regulate excitable or inhibitory interneurons, and specifically to target β2-AR signal pathways to re-establish neuroimmune balance. These will help us design effective strategies to reverse post-SCI sympathetic hyperreflexia and improve the overall quality of life for individuals with SCI.
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Affiliation(s)
- Ping Yang
- Department of Neurobiology, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Zhi-Qun Bian
- Department of Orthopedics, The Second Affiliated Hospital of Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Zhen-Bo Song
- Department of Physiology, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Cheng-Ying Yang
- Department of Immunology, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Li Wang
- Department of Immunology, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Zhong-Xiang Yao
- Department of Physiology, Army Medical University (Third Military Medical University), Chongqing 400038, China
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DiSabato DJ, Marion CM, Mifflin KA, Alfredo AN, Rodgers KA, Kigerl KA, Popovich PG, McTigue DM. System failure: Systemic inflammation following spinal cord injury. Eur J Immunol 2024; 54:e2250274. [PMID: 37822141 PMCID: PMC10919103 DOI: 10.1002/eji.202250274] [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: 06/01/2023] [Revised: 10/06/2023] [Accepted: 10/10/2023] [Indexed: 10/13/2023]
Abstract
Spinal cord injury (SCI) affects hundreds of thousands of people in the United States, and while some effects of the injury are broadly recognized (deficits to locomotion, fine motor control, and quality of life), the systemic consequences of SCI are less well-known. The spinal cord regulates systemic immunological and visceral functions; this control is often disrupted by the injury, resulting in viscera including the gut, spleen, liver, bone marrow, and kidneys experiencing local tissue inflammation and physiological dysfunction. The extent of pathology depends on the injury level, severity, and time post-injury. In this review, we describe immunological and metabolic consequences of SCI across several organs. Since infection and metabolic disorders are primary reasons for reduced lifespan after SCI, it is imperative that research continues to focus on these deleterious aspects of SCI to improve life span and quality of life for individuals with SCI.
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Affiliation(s)
- Damon J. DiSabato
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
| | - Christina M. Marion
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
| | - Katherine A. Mifflin
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
| | - Anthony N. Alfredo
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Kyleigh A. Rodgers
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Kristina A. Kigerl
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
| | - Phillip G. Popovich
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
| | - Dana M. McTigue
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, College of Medicine, The Ohio State University, Columbus, Ohio, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
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Milton AJ, Kwok JC, McClellan J, Randall SG, Lathia JD, Warren PM, Silver DJ, Silver J. Recovery of Forearm and Fine Digit Function After Chronic Spinal Cord Injury by Simultaneous Blockade of Inhibitory Matrix Chondroitin Sulfate Proteoglycan Production and the Receptor PTPσ. J Neurotrauma 2023; 40:2500-2521. [PMID: 37606910 PMCID: PMC10698859 DOI: 10.1089/neu.2023.0117] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023] Open
Abstract
Spinal cord injuries (SCI), for which there are limited effective treatments, result in enduring paralysis and hypoesthesia, in part because of the inhibitory microenvironment that develops and limits regeneration/sprouting, especially during chronic stages. Recently, we discovered that targeted enzymatic removal of the inhibitory chondroitin sulfate proteoglycan (CSPG) component of the extracellular and perineuronal net (PNN) matrix via Chondroitinase ABC (ChABC) rapidly restored robust respiratory function to the previously paralyzed hemi-diaphragm after remarkably long times post-injury (up to 1.5 years) following a cervical level 2 lateral hemi-transection. Importantly, ChABC treatment at cervical level 4 in this chronic model also elicited improvements in gross upper arm function. In the present study, we focused on arm and hand function, seeking to highlight and optimize crude as well as fine motor control of the forearm and digits at lengthy chronic stages post-injury. However, instead of using ChABC, we utilized a novel and more clinically relevant systemic combinatorial treatment strategy designed to simultaneously reduce and overcome inhibitory CSPGs. Following a 3-month upper cervical spinal hemi-lesion using adult female Sprague Dawley rats, we show that the combined treatment had a profound effect on functional recovery of the chronically paralyzed forelimb and paw, as well as on precision movements of the digits. The regenerative and immune system related events that we describe deepen our basic understanding of the crucial role of CSPG-mediated inhibition via the PTPσ receptor in constraining functional synaptic plasticity at lengthy time points following SCI, hopefully leading to clinically relevant translational benefits.
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Affiliation(s)
- Adrianna J. Milton
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Jessica C.F. Kwok
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Institute of Experimental Medicine, Czech Academy of Science, Prague, Czech Republic
| | - Jacob McClellan
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Sabre G. Randall
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | - Justin D. Lathia
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine at Case Western Reserve University, Cleveland, Ohio, USA
| | - Philippa M. Warren
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, USA
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Daniel J. Silver
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine at Case Western Reserve University, Cleveland, Ohio, USA
| | - Jerry Silver
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, USA
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Farkas C, Retamal-Fredes E, Ávila A, Fehlings MG, Vidal PM. Degenerative Cervical Myelopathy induces sex-specific dysbiosis in mice. Front Microbiol 2023; 14:1229783. [PMID: 37928672 PMCID: PMC10623434 DOI: 10.3389/fmicb.2023.1229783] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 10/06/2023] [Indexed: 11/07/2023] Open
Abstract
Degenerative Cervical Myelopathy (DCM) is the most common cause of spinal cord impairment in elderly populations. It describes a spectrum of disorders that cause progressive spinal cord compression, neurological impairment, loss of bladder and bowel functions, and gastrointestinal dysfunction. The gut microbiota has been recognized as an environmental factor that can modulate both the function of the central nervous system and the immune response through the microbiota-gut-brain axis. Changes in gut microbiota composition or microbiota-producing factors have been linked to the progression and development of several pathologies. However, little is known about the potential role of the gut microbiota in the pathobiology of DCM. Here, DCM was induced in C57BL/6 mice by implanting an aromatic polyether material underneath the C5-6 laminae. The extent of DCM-induced changes in microbiota composition was assessed by 16S rRNA sequencing of the fecal samples. The immune cell composition was assessed using flow cytometry. To date, several bacterial members have been identified using BLAST against the largest collection of metagenome-derived genomes from the mouse gut. In both, female and males DCM caused gut dysbiosis compared to the sham group. However, dysbiosis was more pronounced in males than in females, and several bacterial members of the families Lachnospiraceae and Muribaculaceae were significantly altered in the DCM group. These changes were also associated with altered microbe-derived metabolic changes in propionate-, butyrate-, and lactate-producing bacterial members. Our results demonstrate that DCM causes dynamic changes over time in the gut microbiota, reducing the abundance of butyrate-producing bacteria, and lactate-producing bacteria to a lesser extent. Genome-scale metabolic modeling using gapseq successfully identified pyruvate-to-butanoate and pyruvate-to-propionate reactions involving genes such as Buk and ACH1, respectively. These results provide a better understanding of the sex-specific molecular effects of changes in the gut microbiota on DCM pathobiology.
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Affiliation(s)
- Carlos Farkas
- Biomedical Science Research Laboratory, Department of Basic Sciences, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Eduardo Retamal-Fredes
- Biomedical Science Research Laboratory, Developmental Neurobiology Unit, Department of Basic Sciences, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Ariel Ávila
- Biomedical Science Research Laboratory, Developmental Neurobiology Unit, Department of Basic Sciences, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Michael G Fehlings
- Department of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Spinal Program, Toronto Western Hospital, University Health Network, Toronto, ON, Canada
| | - Pia M Vidal
- Biomedical Science Research Laboratory, Neuroimmunology and Regeneration of the Central Nervous System Unit, Department of Basic Sciences, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
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9
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Zeng H, Cheng L, Lu DZ, Fan S, Wang KX, Xu LL, Cai B, Zhou MW, Wang JW. Unbiased multitissue transcriptomic analysis reveals complex neuroendocrine regulatory networks mediated by spinal cord injury-induced immunodeficiency. J Neuroinflammation 2023; 20:219. [PMID: 37775760 PMCID: PMC10543323 DOI: 10.1186/s12974-023-02906-7] [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: 04/13/2023] [Accepted: 09/26/2023] [Indexed: 10/01/2023] Open
Abstract
BACKGROUND Spinal cord injury (SCI), which causes loss of sensory and motor function in the body below the level of injury, is a devastating disease of the central nervous system. SCI leads to severe secondary immunosuppression, called SCI-induced immunodeficiency syndrome (SCI-IDS), which is characterized by increased susceptibility to infection and further exacerbates neurological dysfunction. Several studies have suggested that SCI-IDS is an independent risk factor for poor neurological prognosis. SCI-IDS predominantly occurs following injury above the T5 levels and eventually leads to systemic immune failure, possibly via the sympathetic-adrenal medullary axis and the hypothalamic‒pituitary‒adrenal (HPA) axis. However, the mechanism remains unclear. METHODS AND OBJECTIVES The concentrations of adrenocorticotropic hormone and cortisol in plasma, as well as changes in sympathetic activity (blood pressure and catecholamine levels in plasma), were assessed in rats in the high-level (T3) spinal cord injury (T3-SCI) group and the low-level (T10) spinal cord injury (T10-SCI) group. Second, the differential regulation of the gene network between the sympathetic-adrenal medullary axis and the HPA axis was explored by histology and multitissue transcriptomics, and the neuroendocrine-immune network associated with SCI-IDS was further elucidated. RESULTS The spleen and thymus gland, which are secondary immune organs, were significantly atrophied in rats in the T3-SCI group, and the white pulp of the spleen was significantly atrophied. The level of cortisol, which is mediated by the adrenal glands, was markedly elevated, but norepinephrine levels were markedly decreased. There was no difference in adrenocorticotropic hormone expression between any of the groups. The transcriptome analysis results showed that the downregulated differentially expressed genes (DEGs) in the T3-SCI group were enriched in the GO term immunoregulation, indicating that splenic immune function was markedly impaired after high-level SCI. The upregulated DEGs in the hypothalamus (hub genes: Nod2, Serpine1, Cebpb, Nfkbil1, Ripk2, Zfp36, Traf6, Akap8, Gfer, Cxcl10, Tnfaip3, Icam1, Fcgr2b, Ager, Dusp10, and Mapkapk2) were significantly enriched in inflammatory pathways, and the downregulated genes (hub genes: Grm4, Nmu, P2ry12, rt1-bb1, Oprm1, Zfhx2, Gpr83, and Chrm2) were enriched in pathways related to inhibitory Gi-mediated G protein-coupled receptor (Gi-GPCR) neurons and neuropeptide changes. The upregulated genes in the adrenal glands (hub genes: Ciart, per2, per3, cry1, and cry2) were enriched in cortisol secretion and circadian rhythm changes, and the downregulated genes (hub genes: IL7r, rt1-bb, rt1-bb1, rt1-da, rt1-ba, cd74, cxcr3, vcam1, ccl5, bin1, and IL8) were significantly enriched in MHC-mediated immune responses. CONCLUSIONS To explore the possible mechanism underlying SCI-IDS, this study assessed the differential regulation of the gene network associated with neuroendocrine immunity after SCI. Progressive neuroinflammation spreads after injury, and neurotransmission through Gi-mediated G protein-coupled receptors in the HPA axis and neuropeptide production by the hypothalamus are inhibited. Disruption of the connection between the hypothalamus and the adrenal glands causes autonomous regulation of the adrenal glands, disturbance of circadian rhythm and finally hypercortisolemia, leading to general suppression of peripheral adaptive immunity. Neuraxial nerve inflammation caused by SCI persists indefinitely, blocking nerve repair; persistent system-wide immunosuppression in the periphery results in increased susceptibility to infection, leading to poor neurological prognosis.
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Affiliation(s)
- Hong Zeng
- Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 500 Quxi Road, Shanghai, 200011 China
- Department of Orthopedic Surgery, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011 China
| | - Li Cheng
- Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 500 Quxi Road, Shanghai, 200011 China
| | - De-zhi Lu
- School of Medicine, Shanghai University, Shanghai, 200444 China
| | - Shuai Fan
- Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 500 Quxi Road, Shanghai, 200011 China
| | - Ke-xin Wang
- Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 500 Quxi Road, Shanghai, 200011 China
| | - Li-li Xu
- Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 500 Quxi Road, Shanghai, 200011 China
| | - Bin Cai
- Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 500 Quxi Road, Shanghai, 200011 China
| | - Mou-wang Zhou
- Department of Rehabilitation Medicine, Peking University Third Hospital, 49 North Garden Road, Beijing, 100191 China
| | - Jin-wu Wang
- Department of Orthopedic Surgery, Shanghai Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011 China
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10
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Pukos N, Marion CM, Arnold WD, Noble BT, Popovich PG, McTigue DM. Chronic demyelination and myelin repair after spinal cord injury in mice: A potential link for glutamatergic axon activity. Glia 2023; 71:2096-2116. [PMID: 37208933 PMCID: PMC10330449 DOI: 10.1002/glia.24382] [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: 02/03/2023] [Revised: 04/08/2023] [Accepted: 04/20/2023] [Indexed: 05/21/2023]
Abstract
Our prior work examining endogenous repair after spinal cord injury (SCI) in mice revealed that large numbers of new oligodendrocytes (OLs) are generated in the injured spinal cord, with peak oligodendrogenesis between 4 and 7 weeks post-injury (wpi). We also detected new myelin formation over 2 months post-injury (mpi). Our current work significantly extends these results, including quantification of new myelin through 6 mpi and concomitant examination of indices of demyelination. We also examined electrophysiological changes during peak oligogenesis and a potential mechanism driving OL progenitor cell (OPC) contact with axons. Results reveal peak in remyelination occurs during the 3rd mpi, and that myelin generation continues for at least 6 mpi. Further, motor evoked potentials significantly increased during peak remyelination, suggesting enhanced axon potential conduction. Interestingly, two indices of demyelination, nodal protein spreading and Nav1.2 upregulation, were also present chronically after SCI. Nav1.2 was expressed through 10 wpi and nodal protein disorganization was detectable throughout 6 mpi suggesting chronic demyelination, which was confirmed with EM. Thus, demyelination may continue chronically, which could trigger the long-term remyelination response. To examine a potential mechanism that may initiate post-injury myelination, we show that OPC processes contact glutamatergic axons in the injured spinal cord in an activity-dependent manner. Notably, these OPC/axon contacts were increased 2-fold when axons were activated chemogenetically, revealing a potential therapeutic target to enhance post-SCI myelin repair. Collectively, results show the surprisingly dynamic nature of the injured spinal cord over time and that the tissue may be amenable to treatments targeting chronic demyelination.
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Affiliation(s)
- Nicole Pukos
- Neuroscience Graduate Program, Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, Ohio State University, Columbus, Ohio, USA
| | - Christina M Marion
- Belford Center for Spinal Cord Injury, Ohio State University, Columbus, Ohio, USA
- Department of Neuroscience, College of Medicine, Ohio State University, Columbus, Ohio, USA
| | - W David Arnold
- Department of Neuroscience, College of Medicine, Ohio State University, Columbus, Ohio, USA
- Division of Neuromuscular Disorders, Department of Neurology, Wexner Medical Center, Ohio State University, Columbus, Ohio, USA
- Department of Physical Medicine and Rehabilitation, Wexner Medical Center, Ohio State University, Columbus, Ohio, USA
- Department of Physiology and Cell Biology, College of Medicine, Ohio State University, Columbus, Ohio, USA
| | - Benjamin T Noble
- Neuroscience Graduate Program, Ohio State University, Columbus, Ohio, USA
- Belford Center for Spinal Cord Injury, Ohio State University, Columbus, Ohio, USA
| | - Phillip G Popovich
- Belford Center for Spinal Cord Injury, Ohio State University, Columbus, Ohio, USA
- Department of Neuroscience, College of Medicine, Ohio State University, Columbus, Ohio, USA
| | - Dana M McTigue
- Belford Center for Spinal Cord Injury, Ohio State University, Columbus, Ohio, USA
- Department of Neuroscience, College of Medicine, Ohio State University, Columbus, Ohio, USA
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11
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Punjani N, Deska-Gauthier D, Hachem LD, Abramian M, Fehlings MG. Neuroplasticity and regeneration after spinal cord injury. NORTH AMERICAN SPINE SOCIETY JOURNAL 2023; 15:100235. [PMID: 37416090 PMCID: PMC10320621 DOI: 10.1016/j.xnsj.2023.100235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/05/2023] [Accepted: 06/05/2023] [Indexed: 07/08/2023]
Abstract
Spinal cord injury (SCI) is a debilitating condition with significant personal, societal, and economic burden. The highest proportion of traumatic injuries occur at the cervical level, which results in severe sensorimotor and autonomic deficits. Following the initial physical damage associated with traumatic injuries, secondary pro-inflammatory, excitotoxic, and ischemic cascades are initiated further contributing to neuronal and glial cell death. Additionally, emerging evidence has begun to reveal that spinal interneurons undergo subtype specific neuroplastic circuit rearrangements in the weeks to months following SCI, contributing to or hindering functional recovery. The current therapeutic guidelines and standards of care for SCI patients include early surgery, hemodynamic regulation, and rehabilitation. Additionally, preclinical work and ongoing clinical trials have begun exploring neuroregenerative strategies utilizing endogenous neural stem/progenitor cells, stem cell transplantation, combinatorial approaches, and direct cell reprogramming. This review will focus on emerging cellular and noncellular regenerative therapies with an overview of the current available strategies, the role of interneurons in plasticity, and the exciting research avenues enhancing tissue repair following SCI.
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Affiliation(s)
- Nayaab Punjani
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Dylan Deska-Gauthier
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Laureen D. Hachem
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Surgery, Division of Neurosurgery and Spine Program, University of Toronto, Toronto, ON, Canada
| | - Madlene Abramian
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Michael G. Fehlings
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Surgery, Division of Neurosurgery and Spine Program, University of Toronto, Toronto, ON, Canada
- Division of Neurosurgery, Krembil Neuroscience Centre, Toronto Western Hospital, University Health Network, Toronto, ON, Canada
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12
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Michael FM, Patel SP, Bachstetter AD, Rabchevsky AG. Proinflammatory and Immunomodulatory Gene and Protein Expression Patterns in Spinal Cord and Spleen Following Acute and Chronic High Thoracic Injury. J Inflamm Res 2023; 16:3341-3349. [PMID: 37576153 PMCID: PMC10423003 DOI: 10.2147/jir.s417435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 08/04/2023] [Indexed: 08/15/2023] Open
Abstract
Introduction In addition to paralysis and loss of sensation, high-level spinal cord injury (SCI) causes sympathetic dysfunction that can lead to autonomic dysreflexia (AD) and chronic immune suppression involving splenic leukopenia. Evidence has shown that treatment with either gabapentin or blockade of TNFα mitigates maladaptive plasticity and the underlying hemodynamic dysfunction, spleen atrophy, and immune dysfunction associated with AD. Because significant improvements long term was noted following treatments only during acute stages of recovery, we sought to systematically examine changes in proinflammatory and immunomodulatory cytokines to ascertain the reason. Methods Adult female Wistar rats underwent complete T4 spinal transection before euthanasia at systematic intervals from 3 days to 8 weeks after injury. Using qRT-PCR and meso scale discovery (MSD) assays, the gene and protein expression of TNFα and IFNγ in the spleen, upper thoracic (T4-9) and lumbosacral (L5-S6) spinal cords were analyzed. Results We found that spleen atrophy occurs in a biphasic manner compared to naïve controls, with significant decreases in the spleen mass noted at 3 days and 8 weeks after injury. Splenic TNFα mRNA and protein levels did not change significantly over time, while IFNγ gene expression dipped acutely with trends for increased protein levels at more chronic time points. TNFα protein increased significantly only in thoracic spinal cord segments from 3 to 14 days post-injury. IFNγ mRNA and protein levels remained unelevated in injured spinal cords over time, with trends for increased protein levels at 2 and 8 weeks in the lumbosacral segments. Discussion Novel temporal-spatial cytokine expression profiles reveal that TNFα protein levels are increased solely in upper thoracic segments after high thoracic SCI, while IFNγ remains unaltered. Splenic leukopenia and latent systemic immunosuppression are not associated with altered TNFα or IFNγ expression in the spleen or spinal cord.
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Affiliation(s)
- Felicia M Michael
- Department of Physiology, University of Kentucky, Lexington, KY, 40536-0509, USA
- Spinal Cord & Brain Injury Research Center (SCoBIRC); University of Kentucky, Lexington, KY, 40536-0509, USA
| | - Samir P Patel
- Department of Physiology, University of Kentucky, Lexington, KY, 40536-0509, USA
- Spinal Cord & Brain Injury Research Center (SCoBIRC); University of Kentucky, Lexington, KY, 40536-0509, USA
| | - Adam D Bachstetter
- Spinal Cord & Brain Injury Research Center (SCoBIRC); University of Kentucky, Lexington, KY, 40536-0509, USA
- Department of Neuroscience, University of Kentucky, Lexington, KY, 40536-0509, USA
| | - Alexander G Rabchevsky
- Department of Physiology, University of Kentucky, Lexington, KY, 40536-0509, USA
- Spinal Cord & Brain Injury Research Center (SCoBIRC); University of Kentucky, Lexington, KY, 40536-0509, USA
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13
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Samejima S, Shackleton C, Malik RN, Cao K, Bohorquez A, Nightingale TE, Sachdeva R, Krassioukov AV. Spinal Cord Stimulation Prevents Autonomic Dysreflexia in Individuals with Spinal Cord Injury: A Case Series. J Clin Med 2023; 12:jcm12082897. [PMID: 37109234 PMCID: PMC10146034 DOI: 10.3390/jcm12082897] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/04/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Spinal cord injury (SCI) results in severe cardiovascular dysfunction due to the disruption of supraspinal control. Autonomic dysreflexia (AD), an uncontrolled rise in blood pressure in response to peripheral stimuli including common bowel routine, digital anorectal stimulation (DARS), reduces the quality of life, and increases morbidity and mortality. Recently, spinal cord stimulation (SCS) has emerged as a potential intervention to mitigate unstable blood pressure following SCI. The objective of this case series was to test the real-time effect of epidural SCS (eSCS) at the lumbosacral spinal cord, the most common implant location, on mitigating AD in individuals with SCI. We recruited three individuals with cervical and upper thoracic motor-complete SCI who have an implanted epidural stimulator. We demonstrated that eSCS can reduce the elevation in blood pressure and prevent DARS-induced AD. The blood pressure variability analysis indicated that eSCS potentially reduced vascular sympathetic nervous system activity during DARS, compared to without eSCS. This case series provides evidence to support the use of eSCS to prevent AD episodes during routine bowel procedures, improving the quality of life for individuals with SCI and potentially reducing cardiovascular risks.
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Affiliation(s)
- Soshi Samejima
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
| | - Claire Shackleton
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
| | - Raza N Malik
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
| | - Kawami Cao
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
| | - Anibal Bohorquez
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
- Spinal Cord Program, GF Strong Rehabilitation Centre, Vancouver Coastal Health, Vancouver, BC V5Z 2G9, Canada
| | - Tom E Nightingale
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Centre for Trauma Sciences Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Rahul Sachdeva
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
| | - Andrei V Krassioukov
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC V5Z 2G9, Canada
- Spinal Cord Program, GF Strong Rehabilitation Centre, Vancouver Coastal Health, Vancouver, BC V5Z 2G9, Canada
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14
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Wulf MJ, Tom VJ. Consequences of spinal cord injury on the sympathetic nervous system. Front Cell Neurosci 2023; 17:999253. [PMID: 36925966 PMCID: PMC10011113 DOI: 10.3389/fncel.2023.999253] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 02/09/2023] [Indexed: 03/06/2023] Open
Abstract
Spinal cord injury (SCI) damages multiple structures at the lesion site, including ascending, descending, and propriospinal axons; interrupting the conduction of information up and down the spinal cord. Additionally, axons associated with the autonomic nervous system that control involuntary physiological functions course through the spinal cord. Moreover, sympathetic, and parasympathetic preganglionic neurons reside in the spinal cord. Thus, depending on the level of an SCI, autonomic function can be greatly impacted by the trauma resulting in dysfunction of various organs. For example, SCI can lead to dysregulation of a variety of organs, such as the pineal gland, the heart and vasculature, lungs, spleen, kidneys, and bladder. Indeed, it is becoming more apparent that many disorders that negatively affect quality-of-life for SCI individuals have a basis in dysregulation of the sympathetic nervous system. Here, we will review how SCI impacts the sympathetic nervous system and how that negatively impacts target organs that receive sympathetic innervation. A deeper understanding of this may offer potential therapeutic insight into how to improve health and quality-of-life for those living with SCI.
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Affiliation(s)
| | - Veronica J. Tom
- Marion Murray Spinal Cord Research Center, Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, United States
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15
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Soriano JE, Hudelle R, Squair JW, Mahe L, Amir S, Gautier M, Puchalt VP, Barraud Q, Phillips AA, Courtine G. Longitudinal interrogation of sympathetic neural circuits and hemodynamics in preclinical models. Nat Protoc 2023; 18:340-373. [PMID: 36418397 DOI: 10.1038/s41596-022-00764-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 05/27/2022] [Indexed: 11/24/2022]
Abstract
Neurological disorders, including spinal cord injury, result in hemodynamic instability due to the disruption of supraspinal projections to the sympathetic circuits located in the spinal cord. We recently developed a preclinical model that allows the identification of the topology and dynamics through which sympathetic circuits modulate hemodynamics, supporting the development of a neuroprosthetic baroreflex that precisely controls blood pressure in rats, monkeys and humans with spinal cord injuries. Here, we describe the continuous monitoring of arterial blood pressure and sympathetic nerve activity over several months in preclinical models of chronic neurological disorders using commercially available telemetry technologies, as well as optogenetic and neuronal tract-tracing procedures specifically adapted to the sympathetic circuitry. Using a blueprint to construct a negative-pressure chamber, the approach enables the reproduction, in rats, of well-controlled and reproducible episodes of hypotension-mimicking orthostatic challenges already used in humans. Blood pressure variations can thus be directly induced and linked to the molecular, functional and anatomical properties of specific neurons in the brainstem, spinal cord and ganglia. Each procedure can be completed in under 2 h, while the construction of the negative-pressure chamber requires up to 1 week. With training, individuals with a basic understanding of cardiovascular physiology, engineering or neuroscience can collect longitudinal recordings of hemodynamics and sympathetic nerve activity over several months.
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Affiliation(s)
- Jan Elaine Soriano
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland.,Department of Physiology and Pharmacology, Clinical Neurosciences, Cardiac Sciences, Hotchkiss Brain Institute, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Rémi Hudelle
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Jordan W Squair
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland.,Department of Physiology and Pharmacology, Clinical Neurosciences, Cardiac Sciences, Hotchkiss Brain Institute, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Lois Mahe
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Suje Amir
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Matthieu Gautier
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Victor Perez Puchalt
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Quentin Barraud
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Aaron A Phillips
- Department of Physiology and Pharmacology, Clinical Neurosciences, Cardiac Sciences, Hotchkiss Brain Institute, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada.
| | - Gregoire Courtine
- Neuro-X Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland. .,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland. .,Defitech Center for Interventional Neurotherapies (.NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland.
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16
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Sterner RC, Sterner RM. Immune response following traumatic spinal cord injury: Pathophysiology and therapies. Front Immunol 2023; 13:1084101. [PMID: 36685598 PMCID: PMC9853461 DOI: 10.3389/fimmu.2022.1084101] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/19/2022] [Indexed: 01/09/2023] Open
Abstract
Traumatic spinal cord injury (SCI) is a devastating condition that is often associated with significant loss of function and/or permanent disability. The pathophysiology of SCI is complex and occurs in two phases. First, the mechanical damage from the trauma causes immediate acute cell dysfunction and cell death. Then, secondary mechanisms of injury further propagate the cell dysfunction and cell death over the course of days, weeks, or even months. Among the secondary injury mechanisms, inflammation has been shown to be a key determinant of the secondary injury severity and significantly worsens cell death and functional outcomes. Thus, in addition to surgical management of SCI, selectively targeting the immune response following SCI could substantially decrease the progression of secondary injury and improve patient outcomes. In order to develop such therapies, a detailed molecular understanding of the timing of the immune response following SCI is necessary. Recently, several studies have mapped the cytokine/chemokine and cell proliferation patterns following SCI. In this review, we examine the immune response underlying the pathophysiology of SCI and assess both current and future therapies including pharmaceutical therapies, stem cell therapy, and the exciting potential of extracellular vesicle therapy.
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Affiliation(s)
- Robert C. Sterner
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Rosalie M. Sterner
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States,*Correspondence: Rosalie M. Sterner,
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17
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Furlan JC, Loh E, Boulos MI. The potential effects of untreated sleep-related breathing disorders on neuropathic pain, spasticity, and cardiovascular dysfunction following spinal cord injury: A cross-sectional prospective study protocol. PLoS One 2023; 18:e0282860. [PMID: 37130111 PMCID: PMC10153696 DOI: 10.1371/journal.pone.0282860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 02/13/2023] [Indexed: 05/03/2023] Open
Abstract
INTRODUCTION Sleep-related breathing disorders (SRBDs), neuropathic pain, spasticity and cardiovascular autonomic dysfunction are common after spinal cord injury (SCI). Prior studies suggest that systemic inflammation following SCI may be implicated in the development of neuropathic pain, spasticity and cardiovascular dysfunction. Given that SRBDs also cause a systemic inflammatory response, we hypothesized that individuals with SCI who develop more severe SRBDs would experience more intense neuropathic pain, more severe spasticity and more significant cardiovascular autonomic dysfunction. METHODS This cross-sectional prospective study will explore the previously understudied hypothesis that SRBDs are associated with increased neuropathic pain, spasticity, and cardiovascular autonomic dysfunction in adult individuals with low-cervical/high-thoracic (injury level at C5 to T6), complete/incomplete (ASIA Impairment Scale A, B, C or D) SCI. DISCUSSION To our knowledge, no prior study has addressed this clinically relevant question on whether the degree of SRBDs affects the intensity of neuropathic pain, spasticity, and cardiovascular autonomic dysfunction in individuals with SCI. We anticipate that the results of this original study will provide key information for a future clinical trial on the use of continuous positive airway pressure (CPAP) therapy for moderate-to-severe SRBDs, which may better control neuropathic pain, spasticity, and cardiovascular autonomic dysfunction among individuals with SCI. TRIAL REGISTRATION The research protocol for this study was registered in the ClinicalTrials.gov website (NCT05687097). https://clinicaltrials.gov/ct2/show/NCT05687097.
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Affiliation(s)
- Julio Cesar Furlan
- Toronto Rehabilitation Institute, Lyndhurst Centre, University Health Network, Toronto, Ontario, Canada
- KITE Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Medicine, Division of Physical Medicine and Rehabilitation, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada
- Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada
| | - Eldon Loh
- Department of Physical Medicine and Rehabilitation, University of Western Ontario, London, ON, Canada
- Parkwood Institute Research, Lawson Health Research Institute, London, ON, Canada
| | - Mark Iskander Boulos
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Research Institute and Sunnybrook Health Sciences Centre, Hurvitz Brain Sciences Research Program, Toronto, ON, Canada
- Department of Medicine, Division of Neurology, University of Toronto, Toronto, ON, Canada
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18
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Grassner L, Klein B, Garcia-Ovejero D, Mach O, Scheiblhofer S, Weiss R, Vargas-Baquero E, Kramer JLK, Leister I, Rohde E, Oeller M, Molina-Holgado E, Griessenauer CJ, Maier D, Aigner L, Arevalo-Martin A. Systemic Immune Profile Predicts the Development of Infections in Patients with Spinal Cord Injuries. J Neurotrauma 2022; 39:1678-1686. [PMID: 35607859 DOI: 10.1089/neu.2021.0448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Patients with spinal cord injury (SCI) frequently develop infections that may affect quality of life, be life-threatening, and impair their neurological recovery in the acute and subacute injury phases. Therefore, identifying patients with SCI at risk for developing infections in this stage is of utmost importance. We determined the systemic levels of immune cell populations, cytokines, chemokines, and growth factors in 81 patients with traumatic SCI at 4 weeks after injury and compared them with those of 26 age-matched healthy control subjects. Patients who developed infections between 4 and 16 weeks after injury exhibited higher numbers of neutrophils and eosinophils, as well as lower numbers of lymphocytes and eotaxin-1 (CCL11) levels. Accordingly, lasso logistic regression showed that incomplete lesions (American Spinal Injury Association Impairment Scale [AIS] C and D grades), the levels of eotaxin-1, and the number of lymphocytes, basophils, and monocytes are predictive of lower odds for infections. On the other hand, the number of neutrophils and eosinophils as well as, in a lesser extent, the levels of IP-10 (CXCL10), MCP-1 (CCL2), BDNF [brain-derived neurotrophic factor], and vascular endothelial growth factor [VEGF]-A, are predictors of increased susceptibility for developing infections. Overall, our results point to systemic immune disbalance after SCI as predictors of infection in a period when infections may greatly interfere with neurological and functional recovery and suggest new pathways and players to further explore novel therapeutic strategies.
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Affiliation(s)
- Lukas Grassner
- Institute of Molecular Regenerative Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury Center, BG Trauma Center Murnau, Murnau, Germany
| | - Barbara Klein
- Institute of Molecular Regenerative Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Daniel Garcia-Ovejero
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos, SESCAM, Toledo, Spain
| | - Orpheus Mach
- ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury Center, BG Trauma Center Murnau, Murnau, Germany
| | - Sandra Scheiblhofer
- Division of Allergy and Immunology, Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Richard Weiss
- Division of Allergy and Immunology, Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | | | - John L K Kramer
- International Collaboration on Repair Discoveries (ICORD), Pharmacology, and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Anesthesiology, Pharmacology, and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Iris Leister
- Institute of Molecular Regenerative Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury Center, BG Trauma Center Murnau, Murnau, Germany
| | - Eva Rohde
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,Department for Transfusion Medicine, University Hospital of Salzburg (SALK), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Michaela Oeller
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,Department for Transfusion Medicine, University Hospital of Salzburg (SALK), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Eduardo Molina-Holgado
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos, SESCAM, Toledo, Spain
| | - Christoph J Griessenauer
- Department of Neurosurgery, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Doris Maier
- ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury Center, BG Trauma Center Murnau, Murnau, Germany
| | - Ludwig Aigner
- Institute of Molecular Regenerative Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria.,ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria
| | - Angel Arevalo-Martin
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos, SESCAM, Toledo, Spain
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19
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Li C, Wu C, Xu G, Liu Y, Chen J, Zhang J, Hong H, Ji C, Cui Z. CCR7-mediated T follicular helper cell differentiation is associated with the pathogenesis and immune microenvironment of spinal cord injury-induced immune deficiency syndrome. Front Neurosci 2022; 16:1019406. [PMCID: PMC9615471 DOI: 10.3389/fnins.2022.1019406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Spinal cord injury-induced immune deficiency syndrome (SCI-IDS) is a disorder characterized by systemic immunosuppression secondary to SCI that dramatically increases the likelihood of infection and is difficult to treat. T follicular helper (Tfh) cells regulated by chemokine receptor CCR7 are associated with SCI-IDS after acute SCI. The present study explored the roles of CCR7 in SCI-IDS occurrence and immune microenvironment composition. Gene expression profile data of peripheral blood leukocytes from SCI and non-SCI subjects were collected from the Gene Expression Omnibus database. According to differential gene expression analysis, a protein-protein interaction (PPI) network, and risk model construction, the CCR7 expression level was prominently related to acute SCI and CCR7 expression was significantly downregulated after acute SCI. Next, we constructed a clinical prediction model and used it to identify patients with acute SCI. Using Gene Ontology (GO) analysis and gene set enrichment analysis (GSEA), we discovered that immune-related biological processes, such as T cell receptor signaling pathway, were suppressed, whereas chemokine-related signaling pathways were activated after acute SCI. Immune infiltration analysis performed using single sample GSEA and CIBERSORT suggested that Tfh cell function was significantly correlated with the CCR7 expression levels and was considerably reduced after acute SCI. Acute SCI was divided into two subtypes, and we integrated multiple classifiers to analyze and elucidate the immunomodulatory relationships in both subtypes jointly. The results suggested that CCR7 suppresses the immunodeficiency phenotype by activating the chemokine signaling pathway in Tfh cells. In conclusion, CCR7 exhibits potential as a diagnostic marker for acute SCI.
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Affiliation(s)
- Chaochen Li
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
- Key Laboratory for Restoration Mechanism and Clinical Translation of Spinal Cord Injury, Nantong, China
- Research Institute for Spine and Spinal Cord Disease of Nantong University, Nantong, China
| | - Chunshuai Wu
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
- Key Laboratory for Restoration Mechanism and Clinical Translation of Spinal Cord Injury, Nantong, China
- Research Institute for Spine and Spinal Cord Disease of Nantong University, Nantong, China
| | - Guanhua Xu
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
| | - Yang Liu
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
| | - Jiajia Chen
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
| | - Jinlong Zhang
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
| | - Hongxiang Hong
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
| | - Chunyan Ji
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
- Key Laboratory for Restoration Mechanism and Clinical Translation of Spinal Cord Injury, Nantong, China
- Research Institute for Spine and Spinal Cord Disease of Nantong University, Nantong, China
| | - Zhiming Cui
- The First People’s Hospital of Nantong, The Second Affiliated Hospital of Nantong University, Nantong University, Nantong, China
- Key Laboratory for Restoration Mechanism and Clinical Translation of Spinal Cord Injury, Nantong, China
- Research Institute for Spine and Spinal Cord Disease of Nantong University, Nantong, China
- *Correspondence: Zhiming Cui,
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20
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Mota CMD, Madden CJ. Neural control of the spleen as an effector of immune responses to inflammation: mechanisms and treatments. Am J Physiol Regul Integr Comp Physiol 2022; 323:R375-R384. [PMID: 35993560 PMCID: PMC9485006 DOI: 10.1152/ajpregu.00151.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/29/2022] [Accepted: 08/11/2022] [Indexed: 11/22/2022]
Abstract
Immune system responses are a vital defense mechanism against pathogens. Inflammatory mediators finely regulate complex inflammatory responses from initiation to resolution. However, in certain conditions, the inflammation is initiated and amplified, but not resolved. Understanding the biological mechanisms underlying the regulation of the immune response is critical for developing therapeutic alternatives, including pharmaceuticals and bioelectronic tools. The spleen is an important immune effector organ since it orchestrates innate and adaptive immune responses such as pathogen clearance, cytokine production, and differentiation of cells, therefore playing a modulatory role that balances pro- and anti-inflammatory responses. However, modulation of splenic immune activity is a largely unexplored potential therapeutic tool that could be used for the treatment of inflammatory and life-threatening conditions. This review discusses some of the mechanisms controlling neuroimmune communication and the brain-spleen axis.
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Affiliation(s)
- Clarissa M D Mota
- Department of Neurological Surgery, Oregon Health and Science University, Portland, Oregon
| | - Christopher J Madden
- Department of Neurological Surgery, Oregon Health and Science University, Portland, Oregon
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21
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Shnawa A, Lee S, Papatheodorou A, Gibbs K, Stein A, Morrison D, Bloom O. Elevated levels of IgA and IgG2 in individuals with chronic spinal cord injury. J Spinal Cord Med 2022; 45:728-738. [PMID: 33443466 PMCID: PMC9542629 DOI: 10.1080/10790268.2020.1854550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
OBJECTIVES To determine circulating levels of antibodies (IgA, IgM, IgG1-4) in individuals with SCI as compared to uninjured individuals. STUDY DESIGN Prospective, observational study. SETTING Outpatient clinic of a Department of Physical Medicine and Rehabilitation and research institute in an academic medical center. PARTICIPANTS Individuals with chronic (≥ 1 year from injury) SCI and uninjured individuals. OUTCOME MEASURES Serum antibody titers were determined by commercial multiplex ELISA. RESULTS Blood samples were collected from individuals with chronic SCI (N = 29, 83% males) and uninjured individuals (N = 25, 64% males). Among participants with SCI, the distribution of American Spinal Injury Association Impairment Scale (AIS) grades was: A (n = 15), B (n = 2), C (n = 4), D (n = 8). Neurological levels of injury were: cervical (n = 17), thoracic (n = 10), and lumbar (n = 2). IgA levels were significantly elevated in participants with SCI compared to uninjured participants (median: 1.98 vs. 1.21 mg/ml, P < 0.0001), with levels most elevated in individuals with motor complete injuries compared to uninjured participants (P < 0.0003). IgG2 antibodies were also significantly elevated in participants with SCI compared to uninjured participants (median: 5.98 vs. 4.37 mg/ml, P < 0.018). CONCLUSIONS To our knowledge, this study provides the first evidence of elevated IgA, the antibody type most prevalent at respiratory, genitourinary and gastrointestinal tracts, common sites of infections in individuals with SCI. IgG2 levels were also elevated in individuals with SCI. These data support further investigations of IgA and other antibody types in individuals with chronic SCI, which may be increasingly important in the context of emerging novel infectious diseases such as SARS-CoV-2.
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Affiliation(s)
- Aya Shnawa
- Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Samuel Lee
- Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, Manhasset, New York, USA,Department of Surgery, Lenox Hill Hospital, Northwell Health, New York, New York, USA
| | - Angelos Papatheodorou
- Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Katie Gibbs
- Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Adam Stein
- Department of Physical Medicine and Rehabilitation, Zucker School of Medicine at Hofstra Northwell, Northwell Health, Great Neck, New York, USA
| | - Debra Morrison
- Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Ona Bloom
- Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, Manhasset, New York, USA,Department of Physical Medicine and Rehabilitation, Zucker School of Medicine at Hofstra Northwell, Northwell Health, Great Neck, New York, USA,Correspondence to: Ona Bloom, Laboratory of Spinal Cord Injury Research, The Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, New York, USA; Department of Physical Medicine and Rehabilitation, Zucker School of Medicine at Hofstra Northwell, Northwell Health, 1554 Northern Boulevard, Great Neck, New York, USA.
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22
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Takamiya S, Kawabori M, Yamazaki K, Yamaguchi S, Tanimori A, Yamamoto K, Ohnishi S, Seki T, Konno K, Tha KK, Hashimoto D, Watanabe M, Houkin K, Fujimura M. Intravenous transplantation of amnion-derived mesenchymal stem cells promotes functional recovery and alleviates intestinal dysfunction after spinal cord injury. PLoS One 2022; 17:e0270606. [PMID: 35802703 PMCID: PMC9269969 DOI: 10.1371/journal.pone.0270606] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 06/13/2022] [Indexed: 11/19/2022] Open
Abstract
Spinal cord injury (SCI) is often accompanied by gastrointestinal dysfunction due to the disconnection of the spinal autonomic nervous system. Gastrointestinal dysfunction reportedly upregulates intestinal permeability, leading to bacterial translocation of the gut microbiome to the systemic circulation, which further activates systemic inflammation, exacerbating neuronal damage. Mesenchymal stem cells (MSC) reportedly ameliorate SCI. Here, we aimed to investigate their effect on the associated gastrointestinal dysfunction. Human amnion-derived MSC (AMSCs) were intravenously transplanted one day after a rat model of midthoracic SCI. Biodistribution of transplanted cells, behavioral assessment, and histological evaluations of the spinal cord and intestine were conducted to elucidate the therapeutic effect of AMSCs. Bacterial translocation of the gut microbiome was examined by in situ hybridization and bacterial culture of the liver. Systemic inflammations were examined by blood cytokines, infiltrating immune cells in the spinal cord, and the size of the peripheral immune tissue. AMSCs released various neurotrophic factors and were mainly distributed in the liver and lung after transplantation. AMSC-transplanted animals showed smaller spinal damage and better neurological recovery with preserved neuronal tract. AMSCs transplantation ameliorated intestinal dysfunction both morphologically and functionally, which prevented translocation of the gut microbiome to the systemic circulation. Systemic inflammations were decreased in animals receiving AMSCs in the chronic phase. Intravenous AMSC administration during the acute phase of SCI rescues both spinal damage and intestinal dysfunction. Reducing bacterial translocation may contribute to decreasing systemic inflammation.
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Affiliation(s)
- Soichiro Takamiya
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Masahito Kawabori
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
- * E-mail:
| | - Kazuyoshi Yamazaki
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Sho Yamaguchi
- Regenerative Medicine and Cell Therapy Laboratories, Kaneka Corporation, Kobe, Hyogo, Japan
| | - Aki Tanimori
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Koji Yamamoto
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Shunsuke Ohnishi
- Laboratory of Molecular and Cellular Medicine, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Toshitaka Seki
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Kotaro Konno
- Department of Anatomy and Embryology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Khin Khin Tha
- Global Center for Biomedical Science and Engineering, Hokkaido University Faculty of Medicine, Sapporo, Hokkaido, Japan
| | - Daigo Hashimoto
- Department of Hematology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Masahiko Watanabe
- Department of Anatomy and Embryology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Kiyohiro Houkin
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Miki Fujimura
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
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23
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Teratani T, Mikami Y, Kanai T. Neuroimmune crosstalk in the gut and liver. Int Immunol 2022; 34:475-484. [PMID: 35793533 DOI: 10.1093/intimm/dxac033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/04/2022] [Indexed: 02/06/2023] Open
Abstract
It has long been assumed that the nervous system exerts distinct effects on immune functions, given the large number of immune disorders that are affected by mental stress. In fact, many different immune cells have been shown to possess a wide variety of neurotransmitter receptors and receive signals of various neurotransmitters, including acetylcholine and noradrenaline. Compared with the findings on local neuroimmune interactions, limited experimental techniques have so far failed to capture a comprehensive overview of neuroimmune interactions between distant organs and the autonomic nervous system in vivo, and the molecular mechanisms underlying local immune regulation of the nervous system have long remained unclear. However, the recent rapid progress in genetic recombination, microscopy and single-cell analysis has deepened our understanding of the anatomical and physiological functions of peripheral nerves at each organ to which they belong. Furthermore, the development of optogenetic and chemogenetic methods has enabled the artificial modulation of specific neuronal activities, and there has been remarkable progress in elucidation of the interaction between nerves and immune cells in vivo, particularly in barrier organs such as the gastrointestinal tract, respiratory tract and skin. This review focuses on the immunoregulatory mechanisms governed by the autonomic nervous system and outlines the latest findings in the regulation of enteric and hepatic immunity by the nervous system.
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Affiliation(s)
- Toshiaki Teratani
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Keio University School of Medicine, Shinanomachi, Shinjuku-ku, Tokyo, Japan
| | - Yohei Mikami
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Keio University School of Medicine, Shinanomachi, Shinjuku-ku, Tokyo, Japan
| | - Takanori Kanai
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Keio University School of Medicine, Shinanomachi, Shinjuku-ku, Tokyo, Japan.,AMED-CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
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24
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Mifflin KA, Brennan FH, Guan Z, Kigerl KA, Filous AR, Mo X, Schwab JM, Popovich PG. Spinal Cord Injury Impairs Lung Immunity in Mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 209:157-170. [PMID: 35697382 PMCID: PMC9246940 DOI: 10.4049/jimmunol.2200192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/22/2022] [Indexed: 06/15/2023]
Abstract
Pulmonary infection is a leading cause of morbidity and mortality after spinal cord injury (SCI). Although SCI causes atrophy and dysfunction in primary and secondary lymphoid tissues with a corresponding decrease in the number and function of circulating leukocytes, it is unknown whether this SCI-dependent systemic immune suppression also affects the unique tissue-specific antimicrobial defense mechanisms that protect the lung. In this study, we tested the hypothesis that SCI directly impairs pulmonary immunity and subsequently increases the risk for developing pneumonia. Using mouse models of severe high-level SCI, we find that recruitment of circulating leukocytes and transcriptional control of immune signaling in the lung is impaired after SCI, creating an environment that is permissive for infection. Specifically, we saw a sustained loss of pulmonary leukocytes, a loss of alveolar macrophages at chronic time points postinjury, and a decrease in immune modulatory genes, especially cytokines, needed to eliminate pulmonary infections. Importantly, this injury-dependent impairment of pulmonary antimicrobial defense is only partially overcome by boosting the recruitment of immune cells to the lung with the drug AMD3100, a Food and Drug Administration-approved drug that mobilizes leukocytes and hematopoietic stem cells from bone marrow. Collectively, these data indicate that the immune-suppressive effects of SCI extend to the lung, a unique site of mucosal immunity. Furthermore, preventing lung infection after SCI will likely require novel strategies, beyond the use of orthodox antibiotics, to reverse or block tissue-specific cellular and molecular determinants of pulmonary immune surveillance.
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Affiliation(s)
- Katherine A Mifflin
- Department of Neuroscience, The Ohio State University, Columbus, OH
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
| | - Faith H Brennan
- Department of Neuroscience, The Ohio State University, Columbus, OH
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
| | - Zhen Guan
- Department of Neuroscience, The Ohio State University, Columbus, OH
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
| | - Kristina A Kigerl
- Department of Neuroscience, The Ohio State University, Columbus, OH
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
| | - Angela R Filous
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
- Department of Neurology, The Ohio State University, Wexner Medical Center, Columbus, OH; and
| | - Xiaokui Mo
- Department of Biomedical Informatics, The Ohio State University, Center for Biostatistics, Columbus, OH
| | - Jan M Schwab
- Department of Neuroscience, The Ohio State University, Columbus, OH
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
- Department of Neurology, The Ohio State University, Wexner Medical Center, Columbus, OH; and
| | - Phillip G Popovich
- Department of Neuroscience, The Ohio State University, Columbus, OH;
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH
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25
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Zhu L, Huang L, Le A, Wang TJ, Zhang J, Chen X, Wang J, Wang J, Jiang C. Interactions between the Autonomic Nervous System and the Immune System after Stroke. Compr Physiol 2022; 12:3665-3704. [PMID: 35766834 DOI: 10.1002/cphy.c210047] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Acute stroke is one of the leading causes of morbidity and mortality worldwide. Stroke-induced immune-inflammatory response occurs in the perilesion areas and the periphery. Although stroke-induced immunosuppression may alleviate brain injury, it hinders brain repair as the immune-inflammatory response plays a bidirectional role after acute stroke. Furthermore, suppression of the systemic immune-inflammatory response increases the risk of life-threatening systemic bacterial infections after acute stroke. Therefore, it is essential to explore the mechanisms that underlie the stroke-induced immune-inflammatory response. Autonomic nervous system (ANS) activation is critical for regulating the local and systemic immune-inflammatory responses and may influence the prognosis of acute stroke. We review the changes in the sympathetic and parasympathetic nervous systems and their influence on the immune-inflammatory response after stroke. Importantly, this article summarizes the mechanisms on how ANS regulates the immune-inflammatory response through neurotransmitters and their receptors in immunocytes and immune organs after stroke. To facilitate translational research, we also discuss the promising therapeutic approaches modulating the activation of the ANS or the immune-inflammatory response to promote neurologic recovery after stroke. © 2022 American Physiological Society. Compr Physiol 12:3665-3704, 2022.
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Affiliation(s)
- Li Zhu
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, PR China
| | - Leo Huang
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Anh Le
- Washington University in St. Louis, Saint Louis, Missouri, USA
| | - Tom J Wang
- Winston Churchill High School, Potomac, Maryland, USA
| | - Jiewen Zhang
- Department of Neurology, People's Hospital of Zhengzhou University, Zhengzhou, PR China
| | - Xuemei Chen
- Department of Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, PR China
| | - Junmin Wang
- Department of Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, PR China
| | - Jian Wang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, PR China.,Department of Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, PR China
| | - Chao Jiang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, PR China
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26
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Rodgers KA, Kigerl KA, Schwab JM, Popovich PG. Immune dysfunction after spinal cord injury - A review of autonomic and neuroendocrine mechanisms. Curr Opin Pharmacol 2022; 64:102230. [PMID: 35489214 PMCID: PMC9372819 DOI: 10.1016/j.coph.2022.102230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 03/22/2022] [Indexed: 02/05/2023]
Abstract
Infections impair neurological outcome and increase mortality after spinal cord injury (SCI). Emerging data show that pathogens more easily infect individuals with SCI because SCI disrupts neural and humoral control of immune cells, culminating with the development of "SCI-induced immune deficiency syndrome" (SCI-IDS). Here, we review data that implicate autonomic dysfunction and impaired neuroendocrine signaling as key determinants of SCI-IDS. Although it is widely appreciated that mature leukocyte dysfunction is a canonical feature of SCI-IDS, new data indicate that SCI impairs the development and mobilization of immune cell precursors in bone marrow. Thus, this review will also explore how the post-injury acquisition of a "bone marrow failure syndrome" may be the earliest manifestation of SCI-IDS.
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Affiliation(s)
- Kyleigh A Rodgers
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA; Medical Scientist Training Program, The Ohio State University, Columbus, OH, USA
| | - Kristina A Kigerl
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA; Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA; The Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
| | - Jan M Schwab
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA; Medical Scientist Training Program, The Ohio State University, Columbus, OH, USA; Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA; The Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA; Departments of Neurology and Physical Medicine and Rehabilitation, The Ohio State University, Columbus, OH 43210, USA
| | - Phillip G Popovich
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA; Medical Scientist Training Program, The Ohio State University, Columbus, OH, USA; Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA; The Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA.
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27
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Noble BT, Brennan FH, Wang Y, Guan Z, Mo X, Schwab JM, Popovich PG. Thoracic VGluT2 + Spinal Interneurons Regulate Structural and Functional Plasticity of Sympathetic Networks after High-Level Spinal Cord Injury. J Neurosci 2022; 42:3659-3675. [PMID: 35304427 PMCID: PMC9053847 DOI: 10.1523/jneurosci.2134-21.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/25/2022] [Accepted: 02/28/2022] [Indexed: 11/21/2022] Open
Abstract
Traumatic spinal cord injury (SCI) above the major spinal sympathetic outflow (T6 level) disinhibits sympathetic neurons from supraspinal control, causing systems-wide "dysautonomia." We recently showed that remarkable structural remodeling and plasticity occurs within spinal sympathetic circuitry, creating abnormal sympathetic reflexes that exacerbate dysautonomia over time. As an example, thoracic VGluT2+ spinal interneurons (SpINs) become structurally and functionally integrated with neurons that comprise the spinal-splenic sympathetic network and immunological dysfunction becomes progressively worse after SCI. To test whether the onset and progression of SCI-induced sympathetic plasticity is neuron activity dependent, we selectively inhibited (or excited) thoracic VGluT2+ interneurons using chemogenetics. New data show that silencing VGluT2+ interneurons in female and male mice with a T3 SCI, using hM4Di designer receptors exclusively activated by designer drugs (Gi DREADDs), blocks structural plasticity and the development of dysautonomia. Specifically, silencing VGluT2+ interneurons prevents the structural remodeling of spinal sympathetic networks that project to lymphoid and endocrine organs, reduces the frequency of spontaneous autonomic dysreflexia (AD), and reduces the severity of experimentally induced AD. Features of SCI-induced structural plasticity can be recapitulated in the intact spinal cord by activating excitatory hM3Dq-DREADDs in VGluT2+ interneurons. Collectively, these data implicate VGluT2+ excitatory SpINs in the onset and propagation of SCI-induced structural plasticity and dysautonomia, and reveal the potential for neuromodulation to block or reduce dysautonomia after severe high-level SCI.SIGNIFICANCE STATEMENT In response to stress or dangerous stimuli, autonomic spinal neurons coordinate a "fight or flight" response marked by increased cardiac output and release of stress hormones. After a spinal cord injury (SCI), normally harmless stimuli like bladder filling can result in a "false" fight or flight response, causing pathological changes throughout the body. We show that progressive hypertension and immune suppression develop after SCI because thoracic excitatory VGluT2+ spinal interneurons (SpINs) provoke structural remodeling in autonomic networks within below-lesion spinal levels. These pathological changes can be prevented in SCI mice or phenocopied in uninjured mice using chemogenetics to selectively manipulate activity in VGluT2+ SpINs. Targeted neuromodulation of SpINs could prevent structural plasticity and subsequent autonomic dysfunction in people with SCI.
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Affiliation(s)
- Benjamin T Noble
- Department of Neuroscience, Center for Brain and Spinal Cord Repair, Belford Center for Spinal Cord Injury, Wexner Medical Center, The Ohio State University, Columbus, Ohio 43210
| | - Faith H Brennan
- Department of Neuroscience, Center for Brain and Spinal Cord Repair, Belford Center for Spinal Cord Injury, Wexner Medical Center, The Ohio State University, Columbus, Ohio 43210
| | - Yan Wang
- Department of Neuroscience, Center for Brain and Spinal Cord Repair, Belford Center for Spinal Cord Injury, Wexner Medical Center, The Ohio State University, Columbus, Ohio 43210
| | - Zhen Guan
- Department of Neuroscience, Center for Brain and Spinal Cord Repair, Belford Center for Spinal Cord Injury, Wexner Medical Center, The Ohio State University, Columbus, Ohio 43210
| | - Xiaokui Mo
- Center for Biostatistics, The Ohio State University, Columbus, Ohio 43210
| | - Jan M Schwab
- Department of Neurology, Wexner Medical Center, The Ohio State University, Columbus, Ohio 43210
| | - Phillip G Popovich
- Department of Neuroscience, Center for Brain and Spinal Cord Repair, Belford Center for Spinal Cord Injury, Wexner Medical Center, The Ohio State University, Columbus, Ohio 43210
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28
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Chemogenetics as a neuromodulatory approach to treating neuropsychiatric diseases and disorders. Mol Ther 2022; 30:990-1005. [PMID: 34861415 PMCID: PMC8899595 DOI: 10.1016/j.ymthe.2021.11.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 11/12/2021] [Accepted: 11/29/2021] [Indexed: 01/01/2023] Open
Abstract
Chemogenetics enables precise, non-invasive, and reversible modulation of neural activity via the activation of engineered receptors that are pharmacologically selective to endogenous or exogenous ligands. With recent advances in therapeutic gene delivery, chemogenetics is poised to support novel interventions against neuropsychiatric diseases and disorders. To evaluate its translational potential, we performed a scoping review of applications of chemogenetics that led to the reversal of molecular and behavioral deficits in studies relevant to neuropsychiatric diseases and disorders. In this review, we present these findings and discuss the potential and challenges for using chemogenetics as a precision medicine-based neuromodulation strategy.
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29
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Sribnick EA, Popovich PG, Hall MW. Central nervous system injury-induced immune suppression. Neurosurg Focus 2022; 52:E10. [PMID: 35104790 DOI: 10.3171/2021.11.focus21586] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/18/2021] [Indexed: 11/06/2022]
Abstract
Central nervous system trauma is a common cause of morbidity and mortality. Additionally, these injuries frequently occur in younger individuals, leading to lifetime expenses for patients and caregivers and the loss of opportunity for society. Despite this prevalence and multiple attempts to design a neuroprotectant, clinical trials for a pharmacological agent for the treatment of traumatic brain injury (TBI) or spinal cord injury (SCI) have provided disappointing results. Improvements in outcome from these disease processes in the past decades have been largely due to improvements in supportive care. Among the many challenges facing patients and caregivers following neurotrauma, posttraumatic nosocomial infection is a significant and potentially reversible risk factor. Multiple animal and clinical studies have provided evidence of posttraumatic systemic immune suppression, and injuries involving the CNS may be even more prone, leading to a higher risk for in-hospital infections following neurotrauma. Patients who have experienced neurotrauma with nosocomial infection have poorer recovery and higher risks of long-term morbidity and in-hospital mortality than patients without infection. As such, the etiology and reversal of postneurotrauma immune suppression is an important topic. There are multiple possible etiologies for these posttraumatic changes including the release of damage-associated molecular patterns, the activation of immunosuppressive myeloid-derived suppressor cells, and sympathetic nervous system activation. Postinjury systemic immunosuppression, particularly following neurotrauma, provides a challenge for clinicians but also an opportunity for improvement in outcome. In this review, the authors sought to outline the evidence of postinjury systemic immune suppression in both animal models and clinical research of TBI, TBI polytrauma, and SCI.
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Affiliation(s)
- Eric A Sribnick
- 1Department of Neurosurgery, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus.,2The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus
| | - Phillip G Popovich
- 3Department of Neuroscience.,4Center for Brain and Spinal Cord Repair.,5Belford Center for Spinal Cord Injury, and.,6Medical Scientist Training Program, The Ohio State University, College of Medicine, Columbus; and
| | - Mark W Hall
- 2The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus.,7Division of Critical Care Medicine, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio
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30
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Somatosensory and autonomic neuronal regulation of the immune response. Nat Rev Neurosci 2022; 23:157-171. [PMID: 34997214 DOI: 10.1038/s41583-021-00555-4] [Citation(s) in RCA: 78] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2021] [Indexed: 12/11/2022]
Abstract
Bidirectional communication between the peripheral nervous system (PNS) and the immune system is a crucial part of an effective but balanced mammalian response to invading pathogens, tissue damage and inflammatory stimuli. Here, we review how somatosensory and autonomic neurons regulate immune cellular responses at barrier tissues and in peripheral organs. Immune cells express receptors for neuronal mediators, including neuropeptides and neurotransmitters, allowing neurons to influence their function in acute and chronic inflammatory diseases. Distinct subsets of peripheral sensory, sympathetic, parasympathetic and enteric neurons are able to signal to innate and adaptive immune cells to modulate their cellular functions. In this Review, we highlight recent studies defining the molecular mechanisms by which neuroimmune signalling mediates tissue homeostasis and pathology. Understanding the neural circuitry that regulates immune responses can offer novel targets for the treatment of a wide array of diseases.
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31
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Madroñero-Mariscal R, Arévalo-Martín Á, Gutiérrez-Henares F, Rodríguez-Cola M, Alvarez de Mon M, López-Dolado E. Infections and spinal cord injury: Covid-19 and beyond. DIAGNOSIS AND TREATMENT OF SPINAL CORD INJURY 2022. [PMCID: PMC9194494 DOI: 10.1016/b978-0-12-822498-4.00011-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Spinal cord injuries cause not only a loss of mobility and sensibility, but also numerous chronic disorders such as: immunosuppression, higher rates of hypertension, neurogenic bladder, blood circulation impairments, and at T8 or above levels of injury, respiratory muscle weakness that can lead to breathing failure. All these conditions make chronic patients susceptible to infections due to a lowered immune system. The aim of this chapter is to analyze the clinical presentation of Covid-19 in patients with spinal cord injury. The authors pretend to make pause to understand if this emergent disease, which is deadly hitting our general population, behaves in the same way in these special patients, to understand if the spinal cord injury condition is acting as a risk factor for morbidity or not, and why. For this purpose, we want to explore the role that the immune system plays in causing infection in patients with spinal cord injury. Some spinal cord-injured patients develop a dysregulation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, which negatively affects all immune processes. Therefore, the combination of this situation with other locally impaired conditions provide the suitable environment for developing an infection, as it occurs in urinary tract infections, the most frequent infection in these patients, because of the presence of a neurogenic bladder and the use of catheters to facilitate its voiding; or in pulmonary infections, the severest ones, because of the respiratory muscle weakness, dysphagia disorders, pulmonary edema, and the use of ventilators to assist with breathing. The physiopathology of these infections helps us to understand its appropriate diagnosis, treatment, and methods of prevention. Most of the published studies show a tendency of milder initial symptoms and a less severe evolution of the Covid-19 disease in spinal cord-injured patients, but currently further validation is needed to support or reject it. The altered immune response could play a critical role in the clinical presentation of these patients. Close observation of neurofunctional outcomes, especially with the help of the International Standards for Neurological Classification of the Spinal Cord Injury (ISNCSCI) Worksheet, is needed to conclude if this infection produces sensory and motor deficits in these patients. Telemedicine has demonstrated to be a useful and effective tool to provide access to medical healthcare to these chronically affected patients, especially under pandemic restriction.
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32
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Fortino TA, Randelman ML, Hall AA, Singh J, Bloom DC, Engel E, Hoh DJ, Hou S, Zholudeva LV, Lane MA. Transneuronal tracing to map connectivity in injured and transplanted spinal networks. Exp Neurol 2022; 351:113990. [DOI: 10.1016/j.expneurol.2022.113990] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/09/2021] [Accepted: 01/20/2022] [Indexed: 11/24/2022]
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33
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Miller BM, Oderberg IM, Goessling W. Hepatic Nervous System in Development, Regeneration, and Disease. Hepatology 2021; 74:3513-3522. [PMID: 34256416 PMCID: PMC8639644 DOI: 10.1002/hep.32055] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/10/2021] [Accepted: 07/01/2021] [Indexed: 12/12/2022]
Abstract
The liver is innervated by autonomic and sensory fibers of the sympathetic and parasympathetic nervous systems that regulate liver function, regeneration, and disease. Although the importance of the hepatic nervous system in maintaining and restoring liver homeostasis is increasingly appreciated, much remains unknown about the specific mechanisms by which hepatic nerves both influence and are influenced by liver diseases. While recent work has begun to illuminate the developmental mechanisms underlying recruitment of nerves to the liver, evolutionary differences contributing to species-specific patterns of hepatic innervation remain elusive. In this review, we summarize current knowledge on the development of the hepatic nervous system and its role in liver regeneration and disease. We also highlight areas in which further investigation would greatly enhance our understanding of the evolution and function of liver innervation.
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Affiliation(s)
- Bess M. Miller
- Division of Genetics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Isaac M. Oderberg
- Division of Genetics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Wolfram Goessling
- Division of Genetics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Harvard Stem Cell Institute, Cambridge, MA, 02138, USA.,Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, 02139, USA.,Division of Gastroenterology, Massachusetts General Hospital, Boston, MA, 02114, USA.,corresponding author: Contact Information: Wolfram Goessling, MD, PhD, Wang 539B, 55 Fruit Street, Boston, MA 02114,
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34
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Peripheral Immune Dysfunction: A Problem of Central Importance after Spinal Cord Injury. BIOLOGY 2021; 10:biology10090928. [PMID: 34571804 PMCID: PMC8470244 DOI: 10.3390/biology10090928] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/03/2021] [Accepted: 09/10/2021] [Indexed: 12/19/2022]
Abstract
Simple Summary Spinal cord injury can result in an increased vulnerability to infections, but until recently the biological mechanisms behind this observation were not well defined. Immunosuppression and concurrent sustained peripheral inflammation after spinal cord injury have been observed in preclinical and clinical studies, now termed spinal cord injury-induced immune depression syndrome. Recent research indicates a key instigator of this immune dysfunction is altered sympathetic input to lymphoid organs, such as the spleen, resulting in a wide array of secondary effects that can, in turn, exacerbate immune pathology. In this review, we discuss what we know about immune dysfunction after spinal cord injury, why it occurs, and how we might treat it. Abstract Individuals with spinal cord injuries (SCI) exhibit increased susceptibility to infection, with pneumonia consistently ranking as a leading cause of death. Despite this statistic, chronic inflammation and concurrent immune suppression have only recently begun to be explored mechanistically. Investigators have now identified numerous changes that occur in the peripheral immune system post-SCI, including splenic atrophy, reduced circulating lymphocytes, and impaired lymphocyte function. These effects stem from maladaptive changes in the spinal cord after injury, including plasticity within the spinal sympathetic reflex circuit that results in exaggerated sympathetic output in response to peripheral stimulation below injury level. Such pathological activity is particularly evident after a severe high-level injury above thoracic spinal cord segment 6, greatly increasing the risk of the development of sympathetic hyperreflexia and subsequent disrupted regulation of lymphoid organs. Encouragingly, studies have presented evidence for promising therapies, such as modulation of neuroimmune activity, to improve regulation of peripheral immune function. In this review, we summarize recent publications examining (1) how various immune functions and populations are affected, (2) mechanisms behind SCI-induced immune dysfunction, and (3) potential interventions to improve SCI individuals’ immunological function to strengthen resistance to potentially deadly infections.
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35
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Van Steenbergen V, Bareyre FM. Chemogenetic approaches to unravel circuit wiring and related behavior after spinal cord injury. Exp Neurol 2021; 345:113839. [PMID: 34389362 DOI: 10.1016/j.expneurol.2021.113839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/30/2021] [Accepted: 08/08/2021] [Indexed: 01/21/2023]
Abstract
A critical shortcoming of the central nervous system is its limited ability to repair injured nerve connections. Trying to overcome this limitation is not only relevant to understand basic neurobiological principles but also holds great promise to advance therapeutic strategies related, in particular, to spinal cord injury (SCI). With barely any SCI patients re-gaining complete neurological function, there is a high need to understand how we could target and improve spinal plasticity to re-establish neuronal connections into a functional network. The development of chemogenetic tools has proven to be of great value to understand functional circuit wiring before and after injury and to correlate novel circuit formation with behavioral outcomes. This review covers commonly used chemogenetic approaches based on metabotropic receptors and their use to improve our understanding of circuit wiring following spinal cord injury.
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Affiliation(s)
- Valérie Van Steenbergen
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, 81377 Munich, Germany; Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, 82152 Planegg-Martinsried, Germany.
| | - Florence M Bareyre
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, 81377 Munich, Germany; Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, 82152 Planegg-Martinsried, Germany; Munich Cluster of Systems Neurology (SyNergy), 81377 Munich, Germany.
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36
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McCreedy DA, Jalufka FL, Platt ME, Min SW, Kirchhoff MA, Pritchard AL, Reid SK, Manlapaz R, Mihaly E, Butts JC, Iyer NR, Sakiyama-Elbert SE, Crone SA, McDevitt TC. Passive Clearing and 3D Lightsheet Imaging of the Intact and Injured Spinal Cord in Mice. Front Cell Neurosci 2021; 15:684792. [PMID: 34408627 PMCID: PMC8366232 DOI: 10.3389/fncel.2021.684792] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/07/2021] [Indexed: 12/18/2022] Open
Abstract
The spinal cord contains a diverse array of sensory and motor circuits that are essential for normal function. Spinal cord injury (SCI) permanently disrupts neural circuits through initial mechanical damage, as well as a cascade of secondary injury events that further expand the spinal cord lesion, resulting in permanent paralysis. Tissue clearing and 3D imaging have recently emerged as promising techniques to improve our understanding of the complex neural circuitry of the spinal cord and the changes that result from damage due to SCI. However, the application of this technology for studying the intact and injured spinal cord remains limited. Here, we optimized the passive CLARITY technique (PACT) to obtain gentle and efficient clearing of the murine spinal cord without the need for specialized equipment. We demonstrate that PACT clearing enables 3D imaging of multiple fluorescent labels in the spinal cord to assess molecularly defined neuronal populations, acute inflammation, long-term tissue damage, and cell transplantation. Collectively, these procedures provide a framework for expanding the utility of tissue clearing to enhance the study of spinal cord neural circuits, as well as cellular- and tissue-level changes that occur following SCI.
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Affiliation(s)
- Dylan A. McCreedy
- Department of Biology, Texas A&M University, College Station, TX, United States
- Gladstone Institutes, San Francisco, CA, United States
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
- Texas A&M Institute for Neuroscience, College Station, TX, United States
| | - Frank L. Jalufka
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - Madison E. Platt
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - Sun Won Min
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - Megan A. Kirchhoff
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - Anna L. Pritchard
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
| | - Shelby K. Reid
- Texas A&M Institute for Neuroscience, College Station, TX, United States
| | | | - Eszter Mihaly
- Gladstone Institutes, San Francisco, CA, United States
| | | | - Nisha R. Iyer
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, United States
| | | | - Steven A. Crone
- Division of Neurosurgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Department of Neurosurgery, College of Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Todd C. McDevitt
- Gladstone Institutes, San Francisco, CA, United States
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, United States
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37
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O'Reilly ML, Mironets E, Shapiro TM, Crowther K, Collyer E, Bethea JR, Tom VJ. Pharmacological Inhibition of Soluble Tumor Necrosis Factor-Alpha Two Weeks after High Thoracic Spinal Cord Injury Does Not Affect Sympathetic Hyperreflexia. J Neurotrauma 2021; 38:2186-2191. [PMID: 33397170 PMCID: PMC8309421 DOI: 10.1089/neu.2020.7504] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
After a severe, high-level spinal cord injury (SCI), plasticity to intraspinal circuits below injury results in heightened spinal sympathetic reflex activity and detrimentally impacts peripheral organ systems. Such sympathetic hyperreflexia is immediately apparent as an episode of autonomic dysreflexia (AD), a life-threatening condition characterized by sudden hypertension and reflexive bradycardia following below-level sensory inputs; for example, pressure sores or impacted fecal matter. Over time, plasticity within the spinal sympathetic reflex (SSR) circuit contributes to the progressive intensification of AD events, as the frequency and severity of AD events increase greatly beginning ∼2 weeks post-injury (wpi). The neuroimmune system has been implicated in driving sympathetic hyperreflexia, as inhibition of the cytokine soluble tumor necrosis factor-alpha (sTNFα) using the biological mimetic XPro1595 beginning within days post-SCI has been shown to attenuate the development of AD. Here, we sought to further understand the effective therapeutic time window of XPro1595 to diminish sympathetic hyperreflexia, as indicated by AD. We delayed the commencement of continuous intrathecal administration of XPro1595 until 2 weeks after a complete, thoracic level 3 injury in adult rats. We examined the severity of colorectal distension-induced AD biweekly. We found that initiation of sTNFα inhibition at 2 wpi does not attenuate the severity or intensification of sympathetic hyperreflexia compared with saline-treated controls. Coupled with previous data from our group, these findings suggest that central sTNFα signaling must be targeted prior to 2 weeks post-SCI in order to decrease sympathetic hyperreflexia.
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Affiliation(s)
- Micaela L. O'Reilly
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Eugene Mironets
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Tatiana M. Shapiro
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Kallon Crowther
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Eileen Collyer
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - John R. Bethea
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Veronica J. Tom
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
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38
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Ueno M. Restoring neuro-immune circuitry after brain and spinal cord injuries. Int Immunol 2021; 33:311-325. [PMID: 33851981 DOI: 10.1093/intimm/dxab017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 04/13/2021] [Indexed: 12/17/2022] Open
Abstract
Neuro-immune interactions are essential for our body's defense and homeostasis. Anatomical and physiological analyses have shown that the nervous system comprises multiple pathways that regulate the dynamics and functions of immune cells, which are mainly mediated by the autonomic nervous system and adrenal signals. These are disturbed when the neurons and circuits are damaged by diseases of the central nervous system (CNS). Injuries caused by stroke or trauma often cause immune dysfunction by abrogation of the immune-regulating neural pathways, which leads to an increased risk of infections. Here, I review the structures and functions of the neural pathways connecting the brain and the immune system, and the neurogenic mechanisms of immune dysfunction that emerge after CNS injuries. Recent technological advances in manipulating specific neural circuits have added mechanistic aspects of neuro-immune interactions and their dysfunctions. Understanding the neural bases of immune control and their pathological processes will deepen our knowledge of homeostasis and lead to the development of strategies to cure immune deficiencies observed in various CNS disorders.
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Affiliation(s)
- Masaki Ueno
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata University, Niigata, Niigata 951-8585, Japan
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39
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Chio JCT, Xu KJ, Popovich P, David S, Fehlings MG. Neuroimmunological therapies for treating spinal cord injury: Evidence and future perspectives. Exp Neurol 2021; 341:113704. [PMID: 33745920 DOI: 10.1016/j.expneurol.2021.113704] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/01/2021] [Accepted: 03/16/2021] [Indexed: 12/13/2022]
Abstract
Spinal cord injury (SCI) has a complex pathophysiology. Following the initial physical trauma to the spinal cord, which may cause vascular disruption, hemorrhage, mechanical injury to neural structures and necrosis, a series of biomolecular cascades is triggered to evoke secondary injury. Neuroinflammation plays a major role in the secondary injury after traumatic SCI. To date, the administration of systemic immunosuppressive medications, in particular methylprednisolone sodium succinate, has been the primary pharmacological treatment. This medication is given as a complement to surgical decompression of the spinal cord and maintenance of spinal cord perfusion through hemodynamic augmentation. However, the impact of neuroinflammation is complex with harmful and beneficial effects. The use of systemic immunosuppressants is further complicated by the natural onset of post-injury immunosuppression, which many patients with SCI develop. It has been hypothesized that immunomodulation to attenuate detrimental aspects of neuroinflammation after SCI, while avoiding systemic immunosuppression, may be a superior approach. To accomplish this, a detailed understanding of neuroinflammation and the systemic immune responses after SCI is required. Our review will strive to achieve this goal by first giving an overview of SCI from a clinical and basic science context. The role that neuroinflammation plays in the pathophysiology of SCI will be discussed. Next, the positive and negative attributes of the innate and adaptive immune systems in neuroinflammation after SCI will be described. With this background established, the currently existing immunosuppressive and immunomodulatory therapies for treating SCI will be explored. We will conclude with a summary of topics that can be explored by neuroimmunology research. These concepts will be complemented by points to be considered by neuroscientists developing therapies for SCI and other injuries to the central nervous system.
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Affiliation(s)
- Jonathon Chon Teng Chio
- Division of Translational and Experimental Neuroscience, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada.
| | - Katherine Jiaxi Xu
- Human Biology Program, University of Toronto, Wetmore Hall, 300 Huron St., Room 105, Toronto, Ontario M5S 3J6, Canada.
| | - Phillip Popovich
- Department of Neuroscience, Belford Center for Spinal Cord Injury, Center for Brain and Spinal Cord Repair, The Neurological Institute, The Ohio State University, Wexner Medical Center, 410 W. 10(th) Ave., Columbus 43210, USA.
| | - Samuel David
- Centre for Research in Neuroscience and BRaIN Program, The Research Institute of the McGill University Health Centre, 1650 Cedar Ave., Montreal, Quebec H3G 1A4, Canada.
| | - Michael G Fehlings
- Division of Translational and Experimental Neuroscience, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
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40
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Squair JW, Gautier M, Mahe L, Soriano JE, Rowald A, Bichat A, Cho N, Anderson MA, James ND, Gandar J, Incognito AV, Schiavone G, Sarafis ZK, Laskaratos A, Bartholdi K, Demesmaeker R, Komi S, Moerman C, Vaseghi B, Scott B, Rosentreter R, Kathe C, Ravier J, McCracken L, Kang X, Vachicouras N, Fallegger F, Jelescu I, Cheng Y, Li Q, Buschman R, Buse N, Denison T, Dukelow S, Charbonneau R, Rigby I, Boyd SK, Millar PJ, Moraud EM, Capogrosso M, Wagner FB, Barraud Q, Bezard E, Lacour SP, Bloch J, Courtine G, Phillips AA. Neuroprosthetic baroreflex controls haemodynamics after spinal cord injury. Nature 2021; 590:308-314. [PMID: 33505019 DOI: 10.1038/s41586-020-03180-w] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 12/11/2020] [Indexed: 01/30/2023]
Abstract
Spinal cord injury (SCI) induces haemodynamic instability that threatens survival1-3, impairs neurological recovery4,5, increases the risk of cardiovascular disease6,7, and reduces quality of life8,9. Haemodynamic instability in this context is due to the interruption of supraspinal efferent commands to sympathetic circuits located in the spinal cord10, which prevents the natural baroreflex from controlling these circuits to adjust peripheral vascular resistance. Epidural electrical stimulation (EES) of the spinal cord has been shown to compensate for interrupted supraspinal commands to motor circuits below the injury11, and restored walking after paralysis12. Here, we leveraged these concepts to develop EES protocols that restored haemodynamic stability after SCI. We established a preclinical model that enabled us to dissect the topology and dynamics of the sympathetic circuits, and to understand how EES can engage these circuits. We incorporated these spatial and temporal features into stimulation protocols to conceive a clinical-grade biomimetic haemodynamic regulator that operates in a closed loop. This 'neuroprosthetic baroreflex' controlled haemodynamics for extended periods of time in rodents, non-human primates and humans, after both acute and chronic SCI. We will now conduct clinical trials to turn the neuroprosthetic baroreflex into a commonly available therapy for people with SCI.
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Affiliation(s)
- Jordan W Squair
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Neurosurgery, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland.,Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,MD/PhD Training Program, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Matthieu Gautier
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Lois Mahe
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Jan Elaine Soriano
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Andreas Rowald
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Arnaud Bichat
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Newton Cho
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland.,Department of Neurosurgery, University of Toronto, Toronto, Ontario, Canada
| | - Mark A Anderson
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Nicholas D James
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Jerome Gandar
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Anthony V Incognito
- RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Giuseppe Schiavone
- Centre for Neuroprosthetics, Institute of Microengineering, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Zoe K Sarafis
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Achilleas Laskaratos
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Kay Bartholdi
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Robin Demesmaeker
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Salif Komi
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Charlotte Moerman
- Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Bita Vaseghi
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Berkeley Scott
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ryan Rosentreter
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Claudia Kathe
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Jimmy Ravier
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Laura McCracken
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Xiaoyang Kang
- Centre for Neuroprosthetics, Institute of Microengineering, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Nicolas Vachicouras
- Centre for Neuroprosthetics, Institute of Microengineering, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Florian Fallegger
- Centre for Neuroprosthetics, Institute of Microengineering, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Ileana Jelescu
- Center for Biomedical Imaging, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | | | - Qin Li
- Motac Neuroscience Ltd, Manchester, UK
| | | | | | - Tim Denison
- Department of Engineering Science and Clinical Neurosciences, University of Oxford, Oxford, UK.,Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Sean Dukelow
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Radiology, McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, Alberta, Canada
| | - Rebecca Charbonneau
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ian Rigby
- Department of Emergency Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Steven K Boyd
- Department of Radiology, McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, Alberta, Canada
| | - Philip J Millar
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Eduardo Martin Moraud
- Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Marco Capogrosso
- Faculty of Biology, University of Fribourg, Fribourg, Switzerland
| | - Fabien B Wagner
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland.,Institut des Maladies Neurodégénératives, Université de Bordeaux, UMR, 5293, Bordeaux, France
| | - Quentin Barraud
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Erwan Bezard
- Motac Neuroscience Ltd, Manchester, UK.,Institut des Maladies Neurodégénératives, Université de Bordeaux, UMR, 5293, Bordeaux, France.,Institut des Maladies Neurodégénératives, CNRS, UMR, 5293, Bordeaux, France
| | - Stéphanie P Lacour
- Centre for Neuroprosthetics, Institute of Microengineering, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Jocelyne Bloch
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Neurosurgery, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Grégoire Courtine
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland. .,Department of Neurosurgery, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland. .,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland. .,Defitech Center for Interventional Neurotherapies (.NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland.
| | - Aaron A Phillips
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada. .,Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada. .,Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada. .,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada. .,RestoreNetwork, Hotchkiss Brain Institute, Libin Cardiovascular Institute, McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
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41
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Brennan FH, Noble BT, Wang Y, Guan Z, Davis H, Mo X, Harris C, Eroglu C, Ferguson AR, Popovich PG. Acute post-injury blockade of α2δ-1 calcium channel subunits prevents pathological autonomic plasticity after spinal cord injury. Cell Rep 2021; 34:108667. [PMID: 33503436 PMCID: PMC8817229 DOI: 10.1016/j.celrep.2020.108667] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 11/16/2020] [Accepted: 12/28/2020] [Indexed: 12/14/2022] Open
Abstract
After spinal cord injury (SCI), normally innocuous visceral or somatic stimuli can trigger uncontrolled reflex activation of sympathetic circuitry, causing pathological dysautonomia. We show that remarkable structural remodeling and plasticity occur within spinal autonomic circuitry, creating abnormal sympathetic reflexes that promote dysautonomia. However, when mice are treated early after SCI with human-equivalent doses of the US Food and Drug Administration (FDA)-approved drug gabapentin (GBP), it is possible to block multi-segmental excitatory synaptogenesis and abolish sprouting of autonomic neurons that innervate immune organs and sensory afferents that trigger pain and autonomic dysreflexia (AD). This “prophylactic GBP” regimen decreases the frequency and severity of AD and protects against SCI-induced immune suppression. These benefits persist even 1 month after stopping treatment. GBP could be repurposed to prevent dysautonomia in at-risk individuals with high-level SCI. Brennan et al. show that α2δ−1 calcium channel subunits drive remarkable structural reorganization of autonomic circuitry and autonomic dysfunction after spinal cord injury. Early (prophylactic) post-injury treatment with gabapentin, an FDA-approved drug, prevents α2δ−1-dependent structural changes and autonomic dysfunction. Prophylactic gabapentin could be repurposed clinically for at-risk individuals.
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Affiliation(s)
- Faith H Brennan
- Department of Neuroscience, Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH 43210, USA
| | - Benjamin T Noble
- Department of Neuroscience, Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH 43210, USA
| | - Yan Wang
- Department of Neuroscience, Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH 43210, USA
| | - Zhen Guan
- Department of Neuroscience, Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH 43210, USA
| | - Hayes Davis
- Department of Neuroscience, Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH 43210, USA
| | - Xiaokui Mo
- Center for Biomedical Informatics, The Ohio State University, Columbus, OH 43210, USA
| | - Clay Harris
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Cagla Eroglu
- Department of Cell Biology, Duke University Medical Center, and Duke Institute for Brain Sciences, Durham, NC 27710, USA
| | - Adam R Ferguson
- Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, Weill Institute for Neurosciences, University of California, San Francisco (UCSF), San Francisco, CA 94142, USA; San Francisco Veterans Affairs Healthcare System (SFVAHCS), San Francisco, CA, USA
| | - Phillip G Popovich
- Department of Neuroscience, Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH 43210, USA.
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42
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Al Mamun A, Monalisa I, Tul Kubra K, Akter A, Akter J, Sarker T, Munir F, Wu Y, Jia C, Afrin Taniya M, Xiao J. Advances in immunotherapy for the treatment of spinal cord injury. Immunobiology 2020; 226:152033. [PMID: 33321368 DOI: 10.1016/j.imbio.2020.152033] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 10/19/2020] [Accepted: 11/18/2020] [Indexed: 12/11/2022]
Abstract
Spinal cord injury (SCI) is a leading cause of morbidity and disability in the world. Over the past few decades, the exact molecular mechanisms describing secondary, persistent injuries, as well as primary and transient injuries, have attracted massive attention to the clinicians and researchers. Recent investigations have distinctly shown the critical roles of innate and adaptive immune responses in regulating sterile neuroinflammation and functional outcomes after SCI. In past years, some promising advances in immunotherapeutic options have efficaciously been identified for the treatment of SCI. In our narrative review, we have mainly focused on the new therapeutic strategies such as the maturation and apoptosis of immune cells by several agents, mesenchymal stem cells (MSCs) as well as multi-factor combination therapy, which have recently provided novel ideas and prospects for the future treatment of SCI. This article also illustrates the latest progress in clarifying the potential roles of innate and adaptive immune responses in SCI, the progression and specification of prospective immunotherapy and outstanding issues in the area.
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Affiliation(s)
- Abdullah Al Mamun
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035 Zhejiang Province, China
| | - Ilma Monalisa
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh
| | - Khadija Tul Kubra
- Department of Pharmacy, University of Development Alternative, Dhaka 1209, Bangladesh
| | - Afroza Akter
- Department of Microbiology, Noakhali Science and Technology University, Noakhali 3814, Bangladesh
| | - Jaheda Akter
- Department of Pharmacy, International Islamic University Chittagong, Kumira, Chattogram-4318, Chittagong, Bangladesh
| | - Tamanna Sarker
- Department of Pharmacy, University of Asia Pacific, Dhaka 1205, Bangladesh
| | - Fahad Munir
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000 Zhejiang Province, China
| | - Yanqing Wu
- Institute of Life Sciences, Wenzhou University, Wenzhou, 325035 Zhejiang Province, China
| | - Chang Jia
- Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325027 Zhejiang Province, China
| | - Masuma Afrin Taniya
- Department of Life Sciences, School of Environment and Life Sciences, Independent University, Bangladesh, Dhaka 1229, Bangladesh
| | - Jian Xiao
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035 Zhejiang Province, China.
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43
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Monteiro S, Pinho AG, Macieira M, Serre-Miranda C, Cibrão JR, Lima R, Soares-Cunha C, Vasconcelos NL, Lentilhas-Graça J, Duarte-Silva S, Miranda A, Correia-Neves M, Salgado AJ, Silva NA. Splenic sympathetic signaling contributes to acute neutrophil infiltration of the injured spinal cord. J Neuroinflammation 2020; 17:282. [PMID: 32967684 PMCID: PMC7513542 DOI: 10.1186/s12974-020-01945-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 08/26/2020] [Indexed: 02/06/2023] Open
Abstract
Background Alterations in the immune system are a complication of spinal cord injury (SCI) and have been linked to an excessive sympathetic outflow to lymphoid organs. Still unknown is whether these peripheral immune changes also contribute for the deleterious inflammatory response mounted at the injured spinal cord. Methods We analyzed different molecular outputs of the splenic sympathetic signaling for the first 24 h after a thoracic compression SCI. We also analyzed the effect of ablating the splenic sympathetic signaling to the innate immune and inflammatory response at the spleen and spinal cord 24 h after injury. Results We found that norepinephrine (NE) levels were already raised at this time-point. Low doses of NE stimulation of splenocytes in vitro mainly affected the neutrophils’ population promoting an increase in both frequency and numbers. Interestingly, the interruption of the sympathetic communication to the spleen, by ablating the splenic nerve, resulted in reduced frequencies and numbers of neutrophils both at the spleen and spinal cord 1 day post-injury. Conclusion Collectively, our data demonstrates that the splenic sympathetic signaling is involved in the infiltration of neutrophils after spinal cord injury. Our findings give new mechanistic insights into the dysfunctional regulation of the inflammatory response mounted at the injured spinal cord.
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Affiliation(s)
- Susana Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Andreia G Pinho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Mara Macieira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Cláudia Serre-Miranda
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Jorge R Cibrão
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Rui Lima
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Carina Soares-Cunha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Natália L Vasconcelos
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - José Lentilhas-Graça
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Sara Duarte-Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Alice Miranda
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Margarida Correia-Neves
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - António J Salgado
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Nuno A Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal. .,ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal.
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Carpenter RS, Marbourg JM, Brennan FH, Mifflin KA, Hall JCE, Jiang RR, Mo XM, Karunasiri M, Burke MH, Dorrance AM, Popovich PG. Spinal cord injury causes chronic bone marrow failure. Nat Commun 2020; 11:3702. [PMID: 32710081 PMCID: PMC7382469 DOI: 10.1038/s41467-020-17564-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 07/01/2020] [Indexed: 12/15/2022] Open
Abstract
Spinal cord injury (SCI) causes immune dysfunction, increasing the risk of infectious morbidity and mortality. Since bone marrow hematopoiesis is essential for proper immune function, we hypothesize that SCI disrupts bone marrow hematopoiesis. Indeed, SCI causes excessive proliferation of bone marrow hematopoietic stem and progenitor cells (HSPC), but these cells cannot leave the bone marrow, even after challenging the host with a potent inflammatory stimulus. Sequestration of HSPCs in bone marrow after SCI is linked to aberrant chemotactic signaling that can be reversed by post-injury injections of Plerixafor (AMD3100), a small molecule inhibitor of CXCR4. Even though Plerixafor liberates HSPCs and mature immune cells from bone marrow, competitive repopulation assays show that the intrinsic long-term functional capacity of HSPCs is still impaired in SCI mice. Together, our data suggest that SCI causes an acquired bone marrow failure syndrome that may contribute to chronic immune dysfunction.
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Affiliation(s)
- Randall S Carpenter
- Neuroscience Graduate Program, The Ohio State University, Columbus, OH, USA
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA
| | - Jessica M Marbourg
- Neuroscience Graduate Program, The Ohio State University, Columbus, OH, USA
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA
| | - Faith H Brennan
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA
| | - Katherine A Mifflin
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA
| | - Jodie C E Hall
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA
| | - Roselyn R Jiang
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA
| | - Xiaokui M Mo
- Center for Biostatistics and Bioinformatics, The Ohio State University, Columbus, OH, USA
| | - Malith Karunasiri
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Matthew H Burke
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Adrienne M Dorrance
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
- Division of Hematology, The Ohio State University, Columbus, OH, USA
| | - Phillip G Popovich
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA.
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA.
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA.
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45
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O'Reilly ML, Tom VJ. Neuroimmune System as a Driving Force for Plasticity Following CNS Injury. Front Cell Neurosci 2020; 14:187. [PMID: 32792908 PMCID: PMC7390932 DOI: 10.3389/fncel.2020.00187] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/29/2020] [Indexed: 12/15/2022] Open
Abstract
Following an injury to the central nervous system (CNS), spontaneous plasticity is observed throughout the neuraxis and affects multiple key circuits. Much of this spontaneous plasticity can elicit beneficial and deleterious functional outcomes, depending on the context of plasticity and circuit affected. Injury-induced activation of the neuroimmune system has been proposed to be a major factor in driving this plasticity, as neuroimmune and inflammatory factors have been shown to influence cellular, synaptic, structural, and anatomical plasticity. Here, we will review the mechanisms through which the neuroimmune system mediates plasticity after CNS injury. Understanding the role of specific neuroimmune factors in driving adaptive and maladaptive plasticity may offer valuable therapeutic insight into how to promote adaptive plasticity and/or diminish maladaptive plasticity, respectively.
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Affiliation(s)
- Micaela L O'Reilly
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Veronica J Tom
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, United States
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Ueno M, Nakamura Y, Nakagawa H, Niehaus JK, Maezawa M, Gu Z, Kumanogoh A, Takebayashi H, Lu QR, Takada M, Yoshida Y. Olig2-Induced Semaphorin Expression Drives Corticospinal Axon Retraction After Spinal Cord Injury. Cereb Cortex 2020; 30:5702-5716. [PMID: 32564090 DOI: 10.1093/cercor/bhaa142] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/02/2020] [Accepted: 05/03/2020] [Indexed: 12/24/2022] Open
Abstract
Axon regeneration is limited in the central nervous system, which hinders the reconstruction of functional circuits following spinal cord injury (SCI). Although various extrinsic molecules to repel axons following SCI have been identified, the role of semaphorins, a major class of axon guidance molecules, has not been thoroughly explored. Here we show that expression of semaphorins, including Sema5a and Sema6d, is elevated after SCI, and genetic deletion of either molecule or their receptors (neuropilin1 and plexinA1, respectively) suppresses axon retraction or dieback in injured corticospinal neurons. We further show that Olig2+ cells are essential for SCI-induced semaphorin expression, and that Olig2 binds to putative enhancer regions of the semaphorin genes. Finally, conditional deletion of Olig2 in the spinal cord reduces the expression of semaphorins, alleviating the axon retraction. These results demonstrate that semaphorins function as axon repellents following SCI, and reveal a novel transcriptional mechanism for controlling semaphorin levels around injured neurons to create zones hostile to axon regrowth.
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Affiliation(s)
- Masaki Ueno
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata University, Niigata 951-8585, Japan.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.,Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Kawaguchi 332-0012, Japan
| | - Yuka Nakamura
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata University, Niigata 951-8585, Japan.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Hiroshi Nakagawa
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama 484-8506, Japan.,Department of Molecular Neuroscience, WPI Immunology Frontier Research Center, Osaka University, Suita 565-0871, Japan
| | - Jesse K Niehaus
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.,Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Kawaguchi 332-0012, Japan
| | - Mari Maezawa
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Zirong Gu
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.,Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Atsushi Kumanogoh
- Department of Respiratory Medicine, Allergy and Rheumatic Diseases, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan
| | - Hirohide Takebayashi
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata 951-8510, Japan
| | - Qing Richard Lu
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Masahiko Takada
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama 484-8506, Japan
| | - Yutaka Yoshida
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.,Neural Connectivity Development in Physiology and Disease Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
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Kigerl KA, Zane K, Adams K, Sullivan MB, Popovich PG. The spinal cord-gut-immune axis as a master regulator of health and neurological function after spinal cord injury. Exp Neurol 2020; 323:113085. [PMID: 31654639 PMCID: PMC6918675 DOI: 10.1016/j.expneurol.2019.113085] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 09/24/2019] [Accepted: 10/18/2019] [Indexed: 12/13/2022]
Abstract
Most spinal cord injury (SCI) research programs focus only on the injured spinal cord with the goal of restoring locomotor function by overcoming mechanisms of cell death or axon regeneration failure. Given the importance of the spinal cord as a locomotor control center and the public perception that paralysis is the defining feature of SCI, this "spinal-centric" focus is logical. Unfortunately, such a focus likely will not yield new discoveries that reverse other devastating consequences of SCI including cardiovascular and metabolic disease, bladder/bowel dysfunction and infection. The current review considers how SCI changes the physiological interplay between the spinal cord, the gut and the immune system. A suspected culprit in causing many of the pathological manifestations of impaired spinal cord-gut-immune axis homeostasis is the gut microbiota. After SCI, the composition of the gut microbiota changes, creating a chronic state of gut "dysbiosis". To date, much of what we know about gut dysbiosis was learned from 16S-based taxonomic profiling studies that reveal changes in the composition and abundance of various bacteria. However, this approach has limitations and creates taxonomic "blindspots". Notably, only bacteria can be analyzed. Thus, in this review we also discuss how the application of emerging sequencing technologies can improve our understanding of how the broader ecosystem in the gut is affected by SCI. Specifically, metagenomics will provide researchers with a more comprehensive look at post-injury changes in the gut virome (and mycome). Metagenomics also allows changes in microbe population dynamics to be linked to specific microbial functions that can affect the development and progression of metabolic disease, immune dysfunction and affective disorders after SCI. As these new tools become more readily available and used across the research community, the development of an "ecogenomic" toolbox will facilitate an Eco-Systems Biology approach to study the complex interplay along the spinal cord-gut-immune axis after SCI.
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Affiliation(s)
- Kristina A Kigerl
- The Belford Center for Spinal Cord Injury, the Center for Brain and Spinal Cord Repair, Department of Neuroscience, Wexner Medical Center at The Ohio State University, USA
| | - Kylie Zane
- The Ohio State University College of Medicine, USA
| | - Kia Adams
- The Belford Center for Spinal Cord Injury, the Center for Brain and Spinal Cord Repair, Department of Neuroscience, Wexner Medical Center at The Ohio State University, USA
| | - Matthew B Sullivan
- Departments of Microbiology, Civil, Environmental and Geodetic Engineering at The Ohio State University, USA
| | - Phillip G Popovich
- The Belford Center for Spinal Cord Injury, the Center for Brain and Spinal Cord Repair, Department of Neuroscience, Wexner Medical Center at The Ohio State University, USA.
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48
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Eldahan KC, Williams HC, Cox DH, Gollihue JL, Patel SP, Rabchevsky AG. Paradoxical effects of continuous high dose gabapentin treatment on autonomic dysreflexia after complete spinal cord injury. Exp Neurol 2020; 323:113083. [DOI: 10.1016/j.expneurol.2019.113083] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/23/2019] [Accepted: 10/13/2019] [Indexed: 12/15/2022]
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Attenuating Neurogenic Sympathetic Hyperreflexia Robustly Improves Antibacterial Immunity After Chronic Spinal Cord Injury. J Neurosci 2019; 40:478-492. [PMID: 31754014 DOI: 10.1523/jneurosci.2417-19.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 11/11/2019] [Accepted: 11/14/2019] [Indexed: 02/06/2023] Open
Abstract
Spinal cord injury (SCI) disrupts critical physiological systems, including the cardiovascular and immune system. Plasticity of spinal circuits below the injury results in abnormal, heightened sympathetic responses, such as extreme, sudden hypertension that hallmarks life-threatening autonomic dysreflexia. Moreover, such sympathetic hyperreflexia detrimentally impacts other effector organs, including the spleen, resulting in spinal cord injury-induced immunodeficiency. Consequently, infection is a leading cause of mortality after SCI. Unfortunately, there are no current treatments that prophylactically limit sympathetic hyperreflexia to prevent subsequent effector organ dysfunction. The cytokine soluble tumor necrosis factor α (sTNFα) is upregulated in the CNS within minutes after SCI and remains elevated. Here, we report that commencing intrathecal administration of XPro1595, an inhibitor of sTNFα, at a clinically feasible, postinjury time point (i.e., 3 d after complete SCI) sufficiently diminishes maladaptive plasticity within the spinal sympathetic reflex circuit. This results in less severe autonomic dysreflexia, a real-time gauge of sympathetic hyperreflexia, for months postinjury. Remarkably, delayed delivery of the sTNFα inhibitor prevents sympathetic hyperreflexia-associated splenic atrophy and loss of leukocytes to dramatically improve the endogenous ability of chronic SCI rats to fight off pneumonia, a common cause of hospitalization after injury. The improved immune function with XPro1595 correlates with less noradrenergic fiber sprouting and normalized norepinephrine levels in the spleen, indicating that heightened, central sTNFα signaling drives peripheral, norepinephrine-mediated organ dysfunction, a novel mechanism of action. Thus, our preclinical study supports intrathecally targeting sTNFα as a viable strategy to broadly attenuate sympathetic dysregulation, thereby improving cardiovascular regulation and immunity long after SCI.SIGNIFICANCE STATEMENT Spinal cord injury (SCI) significantly disrupts immunity, thus increasing susceptibility to infection, a leading cause of morbidity in those living with SCI. Here, we report that commencing intrathecal administration of an inhibitor of the proinflammatory cytokine soluble tumor necrosis factor α days after an injury sufficiently diminishes autonomic dysreflexia, a real time gauge of sympathetic hyperreflexia, to prevent associated splenic atrophy. This dramatically improves the endogenous ability of chronically injured rats to fight off pneumonia, a common cause of hospitalization. This preclinical study could have a significant impact for broadly improving quality of life of SCI individuals.
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Michael FM, Patel SP, Rabchevsky AG. Intraspinal Plasticity Associated With the Development of Autonomic Dysreflexia After Complete Spinal Cord Injury. Front Cell Neurosci 2019; 13:505. [PMID: 31780900 PMCID: PMC6856770 DOI: 10.3389/fncel.2019.00505] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 10/28/2019] [Indexed: 01/02/2023] Open
Abstract
Traumatic spinal cord injury (SCI) leads to disruption of sensory, motor and autonomic function, and triggers structural, physiological and biochemical changes that cause reorganization of existing circuits that affect functional recovery. Propriospinal neurons (PN) appear to be very plastic within the inhibitory microenvironment of the injured spinal cord by forming compensatory circuits that aid in relaying information across the lesion site and, thus, are being investigated for their potential to promote locomotor recovery after experimental SCI. Yet the role of PN plasticity in autonomic dysfunction is not well characterized, notably, the disruption of supraspinal modulatory signals to spinal sympathetic neurons after SCI at the sixth thoracic spinal segment or above resulting in autonomic dysreflexia (AD). This condition is characterized by unmodulated sympathetic reflexes triggering sporadic hypertension associated with baroreflex mediated bradycardia in response to noxious yet unperceived stimuli below the injury to reduce blood pressure. AD is frequently triggered by pelvic visceral distension (bowel and bladder), and there are documented structural relationships between injury-induced sprouting of pelvic visceral afferent C-fibers. Their excitation of lumbosacral PN, in turn, sprout and relay noxious visceral sensory stimuli to rostral disinhibited thoracic sympathetic preganglionic neurons (SPN) that manifest hypertension. Herein, we review evidence for maladaptive plasticity of PN in neural circuits mediating heightened sympathetic reflexes after complete high thoracic SCI that manifest cardiovascular dysfunction, as well as contemporary research methodologies being employed to unveil the precise contribution of PN plasticity to the pathophysiology underlying AD development.
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Affiliation(s)
- Felicia M Michael
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, United States
| | - Samir P Patel
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, United States
| | - Alexander G Rabchevsky
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, United States
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