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Ghosh M, Lee J, Burke AN, Strong TA, Sagen J, Pearse DD. Sex Dependent Disparities in the Central Innate Immune Response after Moderate Spinal Cord Contusion in Rat. Cells 2024; 13:645. [PMID: 38607084 PMCID: PMC11011714 DOI: 10.3390/cells13070645] [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: 01/31/2024] [Revised: 03/12/2024] [Accepted: 03/29/2024] [Indexed: 04/13/2024] Open
Abstract
Subacute spinal cord injury (SCI) displays a complex pathophysiology associated with pro-inflammation and ensuing tissue damage. Microglia, the resident innate immune cells of the CNS, in concert with infiltrating macrophages, are the primary contributors to SCI-induced inflammation. However, subpopulations of activated microglia can also possess immunomodulatory activities that are essential for tissue remodeling and repair, including the production of anti-inflammatory cytokines and growth factors that are vital for SCI recovery. Recently, reports have provided convincing evidence that sex-dependent differences exist in how microglia function during CNS pathologies and the extent to which these cells contribute to neurorepair and endogenous recovery. Herein we employed flow cytometry and immunohistochemical methods to characterize the phenotype and population dynamics of activated innate immune cells within the injured spinal cord of age-matched male and female rats within the first week (7 days) following thoracic SCI contusion. This assessment included the analysis of pro- and anti-inflammatory markers, as well as the expression of critical immunomodulatory kinases, including P38 MAPK, and transcription factors, such as NFκB, which play pivotal roles in injury-induced inflammation. We demonstrate that activated microglia from the injured spinal cord of female rats exhibited a significantly diminutive pro-inflammatory response, but enhanced anti-inflammatory activity compared to males. These changes included lower levels of iNOS and TLR4 expression but increased levels of ARG-1 and CD68 in females after SCI. The altered expression of these markers is indicative of a disparate secretome between the microglia of males and females after SCI and that the female microglia possesses higher phagocytic capabilities (increased CD68). The examination of immunoregulatory kinases and transcription factors revealed that female microglia had higher levels of phosphorylated P38Thr180/Tyr182 MAPK and nuclear NFκB pp50Ser337 but lower amounts of nuclear NFκB pp65Ser536, suggestive of an attenuated pro-inflammatory phenotype in females compared to males after SCI. Collectively, this work provides novel insight into some of the sex disparities that exist in the innate immune response after SCI and indicates that sex is an important variable when designing and testing new therapeutic interventions or interpretating positive or negative responses to an intervention.
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Affiliation(s)
- Mousumi Ghosh
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; (J.L.); (A.N.B.); (T.A.S.); (J.S.); (D.D.P.)
- The Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- Department of Veterans Affairs, Veterans Affairs Medical Center, Miami, FL 33136, USA
| | - Jinyoung Lee
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; (J.L.); (A.N.B.); (T.A.S.); (J.S.); (D.D.P.)
| | - Ashley N. Burke
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; (J.L.); (A.N.B.); (T.A.S.); (J.S.); (D.D.P.)
| | - Thomas A. Strong
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; (J.L.); (A.N.B.); (T.A.S.); (J.S.); (D.D.P.)
| | - Jacqueline Sagen
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; (J.L.); (A.N.B.); (T.A.S.); (J.S.); (D.D.P.)
- The Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- The Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Damien D. Pearse
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; (J.L.); (A.N.B.); (T.A.S.); (J.S.); (D.D.P.)
- The Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- Department of Veterans Affairs, Veterans Affairs Medical Center, Miami, FL 33136, USA
- The Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- The Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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2
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Metcalfe M, Steward O. PTEN deletion in spinal pathways via retrograde transduction with AAV-RG enhances forelimb motor recovery after cervical spinal cord injury; Sex differences and late-onset pathophysiologies. Exp Neurol 2023; 370:114551. [PMID: 37778650 DOI: 10.1016/j.expneurol.2023.114551] [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] [Received: 07/24/2023] [Revised: 09/08/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Spinal cord injuries (SCI) cause permanent functional impairments due to interruption of motor and sensory pathways. Regeneration of axons does not occur due to lack of intrinsic growth capacity of adult neurons and extrinsic inhibitory factors, especially at the injury site. However, some regeneration can be achieved via deletion of the phosphatase and tensin homolog (PTEN) in cells of origin of spinal pathways. Here, we deployed an AAV variant that is retrogradely transported (AAV-rg) to deliver gene modifying cargos to the cells of origin of multiple pathways interrupted by SCI, testing whether this promoted recovery of motor function. PTENf/f;RosatdTomato mice and control RosatdTomato mice received injections of different doses (number of genome copies, GCs) of AAV-rg/Cre into the cervical spinal cord at the time of a C5 dorsal hemisection injury. Forelimb grip strength was tested over time using a grip strength meter. PTENf/f;RosatdTomato mice with AAV-rg/Cre (PTEN-deleted) exhibited substantial improvements in forelimb gripping ability in comparison to controls. Of note, there were major sex differences in the extent of recovery, with male mice exhibiting greater recovery than females. However, at around 5-7 weeks post-injury/injection, many mice with SCI and AAV-rg-mediated PTEN deletion began to exhibit pathophysiologies involving excessive scratching of the ears and back of the neck and rigid forward extension of the hindlimbs. These pathophysiologies increased in incidence and severity over time. Our results reveal that although intra-spinal injections of AAV-rg/Cre in PTENf/f;RosatdTomato mice can enhance forelimb motor recovery after SCI, late-developing functional abnormalities occur with the experimental conditions used here. Mechanisms underlying late-developing pathophysiologies remain to be defined.
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Affiliation(s)
- Mariajose Metcalfe
- Reeve-Irvine Research Center University of California Irvine School of Medicine, USA; Department of Anatomy & Neurobiology, University of California Irvine School of Medicine, USA
| | - Oswald Steward
- Reeve-Irvine Research Center University of California Irvine School of Medicine, USA; Department of Anatomy & Neurobiology, University of California Irvine School of Medicine, USA; Department of Neurobiology & Behavior, University of California Irvine, USA; Department of Neurosurgery, University of California Irvine School of Medicine, USA.
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3
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Broome ST, Mandwie M, Gorrie CA, Musumeci G, Marzagalli R, Castorina A. Early Alterations of PACAP and VIP Expression in the Female Rat Brain Following Spinal Cord Injury. J Mol Neurosci 2023; 73:724-737. [PMID: 37646964 PMCID: PMC10694121 DOI: 10.1007/s12031-023-02151-w] [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: 04/21/2023] [Accepted: 08/21/2023] [Indexed: 09/01/2023]
Abstract
Previous evidence shows that rapid changes occur in the brain following spinal cord injury (SCI). Here, we interrogated the expression of the neuropeptides pituitary adenylyl cyclase-activating peptide (PACAP), vasoactive intestinal peptides (VIP), and their binding receptors in the rat brain 24 h following SCI. Female Sprague-Dawley rats underwent thoracic laminectomy; half of the rats received a mild contusion injury at the level of the T10 vertebrate (SCI group); the other half underwent sham surgery (sham group). Twenty-four hours post-surgery, the hypothalamus, thalamus, amygdala, hippocampus (dorsal and ventral), prefrontal cortex, and periaqueductal gray were collected. PACAP, VIP, PAC1, VPAC1, and VPAC2 mRNA and protein levels were measured by real-time quantitative polymerase chain reaction and Western blot. In SCI rats, PACAP expression was increased in the hypothalamus (104-141% vs sham) and amygdala (138-350%), but downregulated in the thalamus (35-95%) and periaqueductal gray (58-68%). VIP expression was increased only in the thalamus (175-385%), with a reduction in the amygdala (51-68%), hippocampus (40-75%), and periaqueductal gray (74-76%). The expression of the PAC1 receptor was the least disturbed by SCI, with decrease expression in the ventral hippocampus (63-68%) only. The expression levels of VPAC1 and VPAC2 receptors were globally reduced, with more prominent reductions of VPAC1 vs VPAC2 in the amygdala (21-70%) and ventral hippocampus (72-75%). In addition, VPAC1 downregulation also extended to the dorsal hippocampus (69-70%). These findings demonstrate that as early as 24 h post-SCI, there are region-specific disruptions of PACAP, VIP, and related receptor transcript and protein levels in supraspinal regions controlling higher cognitive functions.
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MESH Headings
- Female
- Rats
- Animals
- Pituitary Adenylate Cyclase-Activating Polypeptide/genetics
- Pituitary Adenylate Cyclase-Activating Polypeptide/metabolism
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide/metabolism
- Rats, Sprague-Dawley
- Receptors, Pituitary Hormone/genetics
- Receptors, Pituitary Hormone/metabolism
- Vasoactive Intestinal Peptide/genetics
- Vasoactive Intestinal Peptide/metabolism
- Receptors, Vasoactive Intestinal Polypeptide, Type I/genetics
- Receptors, Vasoactive Intestinal Polypeptide, Type I/metabolism
- Receptors, Vasoactive Intestinal Peptide, Type II/genetics
- Receptors, Vasoactive Intestinal Peptide, Type II/metabolism
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/genetics
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/metabolism
- Spinal Cord Injuries/metabolism
- Brain/metabolism
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Affiliation(s)
- Sarah Thomas Broome
- Laboratory of Cellular and Molecular Neuroscience (LCMN), School of Life Science, Faculty of Science, University of Technology Sydney, PO Box 123 Broadway, Sydney, NSW, 2007, Australia
| | - Mawj Mandwie
- Laboratory of Cellular and Molecular Neuroscience (LCMN), School of Life Science, Faculty of Science, University of Technology Sydney, PO Box 123 Broadway, Sydney, NSW, 2007, Australia
| | - Catherine A Gorrie
- Neural Injury Research Unit, School of Life Science, Faculty of Science, University of Technology Sydney, Sydney, NSW, Australia
| | - Giuseppe Musumeci
- Department of Biomedical and Biotechnological Sciences, Anatomy, Histology and Movement Sciences Section, School of Medicine, University of Catania, Catania, Italy
| | - Rubina Marzagalli
- Laboratory of Cellular and Molecular Neuroscience (LCMN), School of Life Science, Faculty of Science, University of Technology Sydney, PO Box 123 Broadway, Sydney, NSW, 2007, Australia
| | - Alessandro Castorina
- Laboratory of Cellular and Molecular Neuroscience (LCMN), School of Life Science, Faculty of Science, University of Technology Sydney, PO Box 123 Broadway, Sydney, NSW, 2007, Australia.
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4
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Metcalfe M, Steward O. PTEN deletion in spinal pathways via retrograde transduction with AAV-rg enhances forelimb motor recovery after cervical spinal cord injury; sex differences and late-onset pathophysiologies. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533502. [PMID: 36993317 PMCID: PMC10055283 DOI: 10.1101/2023.03.20.533502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Spinal cord injuries (SCI) cause permanent functional impairments due to interruption of motor and sensory pathways. Regeneration of axons does not occur due to lack of intrinsic growth capacity of adult neurons and extrinsic inhibitory factors, especially at the injury site. However, some regeneration can be achieved via deletion of the phosphatase and tensin homolog (PTEN) in cells of origin of spinal pathways. Here, we deployed an AAV variant that is retrogradely transported (AAV-rg) to deliver gene modifying cargos to the cells of origin of multiple pathways interrupted by SCI, testing whether this promoted recovery of motor function. PTEN f/f ;Rosa tdTomato mice and control Rosa tdTomato mice received injections of different doses (number of genome copies, GCs) of AAV-rg/Cre into the cervical spinal cord at the time of a C5 dorsal hemisection injury. Forelimb grip strength was tested over time using a grip strength meter. PTEN f/f ;Rosa tdTomato mice with AAV-rg/Cre (PTEN-deleted) exhibited substantial improvements in forelimb gripping ability in comparison to controls. Of note, there were major sex differences in the extent of recovery, with male mice exhibiting greater recovery than females. However, at around 5-7 weeks post-injury/injection, many mice with SCI and AAV-rg-mediated PTEN deletion began to exhibit pathophysiologies involving excessive scratching of the ears and back of the neck and rigid forward extension of the hindlimbs. These pathophysiologies increased in incidence and severity over time. Our results reveal that although intra-spinal injections of AAV-rg/Cre in PTEN f/f ;Rosa tdTomato mice can enhance forelimb motor recovery after SCI, late-developing functional abnormalities occur with the experimental conditions used here. Mechanisms underlying late-developing pathophysiologies remain to be defined.
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5
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Stewart AN, Jones LAT, Gensel JC. Improving translatability of spinal cord injury research by including age as a demographic variable. Front Cell Neurosci 2022; 16:1017153. [PMID: 36467608 PMCID: PMC9714671 DOI: 10.3389/fncel.2022.1017153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 11/04/2022] [Indexed: 11/18/2022] Open
Abstract
Pre-clinical and clinical spinal cord injury (SCI) studies differ in study design, particularly in the demographic characteristics of the chosen population. In clinical study design, criteria such as such as motor scores, neurological level, and severity of injury are often key determinants for participant inclusion. Further, demographic variables in clinical trials often include individuals from a wide age range and typically include both sexes, albeit historically most cases of SCI occur in males. In contrast, pre-clinical SCI models predominately utilize young adult rodents and typically use only females. While it is often not feasible to power SCI clinical trials to test multi-variable designs such as contrasting different ages, recent pre-clinical findings in SCI animal models have emphasized the importance of considering age as a biological variable prior to human experiments. Emerging pre-clinical data have identified case examples of treatments that diverge in efficacy across different demographic variables and have elucidated several age-dependent effects in SCI. The extent to which these differing or diverging treatment responses manifest clinically can not only complicate statistical findings and trial interpretations but also may be predictive of worse outcomes in select clinical populations. This review highlights recent literature including age as a biological variable in pre-clinical studies and articulates the results with respect to implications for clinical trials. Based on emerging unpredictable treatment outcomes in older rodents, we argue for the importance of including age as a biological variable in pre-clinical animal models prior to clinical testing. We believe that careful analyses of how age interacts with SCI treatments and pathophysiology will help guide clinical trial design and may improve both the safety and outcomes of such important efforts.
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Affiliation(s)
- Andrew N. Stewart
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, United States,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Linda A. T. Jones
- Center for Outcomes and Measurement, Jefferson College of Rehabilitation Sciences, Thomas Jefferson University, Philadelphia, PA, United States
| | - John C. Gensel
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, United States,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States,*Correspondence: John C. Gensel,
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6
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Smith AN, Shaughness M, Collier S, Hopkins D, Byrnes KR. Therapeutic targeting of microglia mediated oxidative stress after neurotrauma. Front Med (Lausanne) 2022; 9:1034692. [PMID: 36405593 PMCID: PMC9671221 DOI: 10.3389/fmed.2022.1034692] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 10/12/2022] [Indexed: 10/06/2023] Open
Abstract
Inflammation is a primary component of the central nervous system injury response. Traumatic brain and spinal cord injury are characterized by a pronounced microglial response to damage, including alterations in microglial morphology and increased production of reactive oxygen species (ROS). The acute activity of microglia may be beneficial to recovery, but continued inflammation and ROS production is deleterious to the health and function of other cells. Microglial nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX), mitochondria, and changes in iron levels are three of the most common sources of ROS. All three play a significant role in post-traumatic brain and spinal cord injury ROS production and the resultant oxidative stress. This review will evaluate the current state of therapeutics used to target these avenues of microglia-mediated oxidative stress after injury and suggest avenues for future research.
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Affiliation(s)
- Austin N. Smith
- Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Michael Shaughness
- Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Sean Collier
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Deanna Hopkins
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Kimberly R. Byrnes
- Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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Osimanjiang W, Allgood JE, Van Sandt RL, Burns DT, Bushman JS. Sexual Dimorphism in Lesion Size and Sensorimotor Responses Following Spinal Cord Injury. Front Neurol 2022; 13:925797. [PMID: 36994113 PMCID: PMC10041393 DOI: 10.3389/fneur.2022.925797] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/31/2022] [Indexed: 03/14/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating disorder, which impacts the lives of millions of people worldwide with no clinically standardized treatment. Both pro-recovery and anti-recovery factors contribute to the overall outcome after the initial SCI. Sex is emerging as an important variable, which can affect recovery post-SCI. Contusion SCI at T10 was generated in male and female rats. Open-field Basso, Beattie, Bresnahan (BBB) behavioral test, Von Frey test, and CatWalk gate analysis were performed. Histological analysis was performed at the 45-day post-SCI end point. Male/female differences in sensorimotor function recovery, lesion size, and the recruitment of immune cells to the lesion area were measured. A group of males with less severe injuries was included to compare the outcomes for severity. Our results show that both sexes with the same injury level plateaued at a similar final score for locomotor function. Males in the less severe injury group recovered faster and plateaued at a higher BBB score compared to the more severe injury group. Von Frey tests show faster recovery of sensory function in females compared to both male groups. All three groups exhibited reduced mechanical response thresholds after SCI. The lesion area was significantly larger in the male group with severe injury than in females, as well as in males of less severe injury. No significant differences in immune cell recruitment were identified when comparing the three groups. The faster sensorimotor recovery and significantly smaller lesion area in females potentially indicate that neuroprotection against the secondary injury is a likely reason for sex-dependent differences in functional outcomes after SCI.
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Affiliation(s)
- Wupu Osimanjiang
- Division of Pharmaceutical Sciences, University of Wyoming, Laramie, WY, United States
| | - JuliAnne E. Allgood
- Division of Pharmaceutical Sciences, University of Wyoming, Laramie, WY, United States
| | - Rae L. Van Sandt
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, United States
| | - Daniel T. Burns
- Division of Pharmaceutical Sciences, University of Wyoming, Laramie, WY, United States
| | - Jared S. Bushman
- Division of Pharmaceutical Sciences, University of Wyoming, Laramie, WY, United States
- *Correspondence: Jared S. Bushman
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Chio JCT, Punjani N, Hejrati N, Zavvarian MM, Hong J, Fehlings MG. Extracellular Matrix and Oxidative Stress Following Traumatic Spinal Cord Injury: Physiological and Pathophysiological Roles and Opportunities for Therapeutic Intervention. Antioxid Redox Signal 2022; 37:184-207. [PMID: 34465134 DOI: 10.1089/ars.2021.0120] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Significance: Traumatic spinal cord injury (SCI) causes significant disruption to neuronal, glial, vascular, and extracellular elements. The spinal cord extracellular matrix (ECM) comprises structural and communication proteins that are involved in reparative and regenerative processes after SCI. In the healthy spinal cord, the ECM helps maintain spinal cord homeostasis. After SCI, the damaged ECM limits plasticity and contributes to inflammation through the expression of damage-associated molecules such as proteoglycans. Recent Advances: Considerable insights have been gained by characterizing the origins of the gliotic and fibrotic scars, which not only reduce the spread of injury but also limit neuroregeneration. These properties likely limit the success of therapies used to treat patients with SCI. The ECM, which is a major contributor to the scars and normal physiological functions of the spinal cord, represents an exciting therapeutic target to enhance recovery post-SCI. Critical Issue: Various ECM-based preclinical therapies have been developed. These include disrupting scar components, inhibiting activity of ECM metalloproteinases, and maintaining iron homeostasis. Biomaterials have also been explored. However, the majority of these treatments have not experienced successful clinical translation. This could be due to the ECM and scars' polarizing roles. Future Directions: This review surveys the complexity involved in spinal ECM modifications, discusses new ECM-based combinatorial strategies, and explores the biomaterials evaluated in clinical trials, which hope to introduce new treatments that enhance recovery after SCI. These topics will incorporate oxidative species, which are both beneficial and harmful in reparative and regenerative processes after SCI, and not often assessed in pertinent literature. Antioxid. Redox Signal. 37, 184-207.
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Affiliation(s)
- Jonathon Chon Teng Chio
- Department of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada
| | - Nayaab Punjani
- Department of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada
| | - Nader Hejrati
- Department of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Canada
| | - Mohammad-Masoud Zavvarian
- Department of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada
| | - James Hong
- Department of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Canada
| | - Michael G Fehlings
- Department of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada.,Department of Surgery and Spine Program, University of Toronto, Toronto, Canada
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9
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Astrocytic Nrf2 expression protects spinal cord from oxidative stress following spinal cord injury in a male mouse model. J Neuroinflammation 2022; 19:134. [PMID: 35668451 PMCID: PMC9169394 DOI: 10.1186/s12974-022-02491-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 05/21/2022] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Spinal cord injury (SCI) induces a multitude of deleterious processes, including neuroinflammation and oxidative stress (OS) which contributed to neuronal damage and demyelination. Recent studies have suggested that increased formation of reactive oxygen species (ROS) and the consequent OS are critical events associated with SCI. However, there is still little information regarding the impact of these events on SCI. Astrocytes are key regulators of oxidative homeostasis in the CNS and astrocytic antioxidant responses promote the clearance of oxidants produced by neurons. Therefore, dysregulation of astrocyte physiology might largely contribute to oxidative damage. Nuclear factor erythroid 2-related factor 2 (Nrf2) is the main transcriptional regulator of cellular anti-oxidative stress responses. METHODS In the current study, we hypothesized that astrocytic activation of Nrf2 protects the spinal cord post injury via suppression of neuroinflammation. Thus, using mice line with a GFAP-specific kelch-like ECH-associated protein 1 (Keap1)-deletion, we induced a hyperactivation of Nrf2 in astrocytes and further its effects on SCI outcomes. SCI-induction was performed in mice using the Infinite Horizon Spinal Cord Impactor with a force of 60 kdyn. To assess the quantitative pattern of Nrf2/ARE-activation, we included transgenic ARE-Luc mice. Data were analyzed with GraphPad Prism 8 (GraphPad Software Inc., San Diego, CA, USA). Brown-Forsythe test was performed to test for equal variances and normal distribution was tested with Shapiro-Wilk. RESULTS In ARE-Luc mice, a significant induction of luciferase-activity was observed as early as 1 day post-injury, indicating a functional role of Nrf2-activity at the epicenter of SCI. Furthermore, SCI induced loss of neurons and oligodendrocytes, demyelination and inflammation in wild type mice. The loss of myelin and oligodendrocytes was clearly reduced in Keap1 KO mice. In addition, Keap-1 KO mice showed a significantly better locomotor function and lower neuroinflammation responses compared to wild type mice. CONCLUSIONS In summary, our in vivo bioluminescence data showed Nrf2-ARE activation during primary phase of SCI. Furthermore, we found that cell specific hyperactivation of Nrf2 was sufficient to protect the spinal cord against injury which indicate a promising therapeutic approach for SCI-treatment.
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10
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Li Y, Ritzel RM, Lei Z, Cao T, He J, Faden AI, Wu J. Sexual dimorphism in neurological function after SCI is associated with disrupted neuroinflammation in both injured spinal cord and brain. Brain Behav Immun 2022; 101:1-22. [PMID: 34954073 PMCID: PMC8885910 DOI: 10.1016/j.bbi.2021.12.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/29/2021] [Accepted: 12/18/2021] [Indexed: 10/19/2022] Open
Abstract
Whereas human spinal cord injury (SCI) is more common in men, the prevalence is growing in women. However, little is known about the effect of biological sex on brain dysfunction and injury mechanisms. To model the highest per capita rate of injury (ages between 16 and 30 years old) in humans, in the present study, young adult or a young/middle-aged male and female C57BL/6 mice were subjected to moderate contusion SCI. When mice were injured at 10-12-week-old, transcriptomic analysis of inflammation-related genes and flow cytometry revealed a more aggressive neuroinflammatory profile in male than females following 3 d SCI, ostensibly driven by sex-specific changes myeloid cell function rather than cell number. Female mice were generally more active at baseline, as evidenced by greater distance traveled in the open field. After SCI, female mice had more favorable locomotor function than male animals. At 13 weeks post-injury, male mice showed poor performance in cognitive and depressive-like behavioral tests, while injured female mice showed fewer deficits in these tasks. However, when injured at 6 months old followed by 8 months post-injury, male mice had considerably less inflammatory activation compared with female animals despite having similar or worse outcomes in affective, cognitive, and motor tasks. Collectively, these findings indicate that sex differences in functional outcome after SCI are associated with the age at onset of injury, as well as disrupted neuroinflammation not only at the site of injury but also in remote brain regions. Thus, biological sex should be considered when designing new therapeutic agents.
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Affiliation(s)
- Yun Li
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD, 21201 USA
| | - Rodney M. Ritzel
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD, 21201 USA
| | - Zhuofan Lei
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD, 21201 USA
| | - Tuoxin Cao
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD, 21201 USA
| | - Junyun He
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD, 21201 USA
| | - Alan I Faden
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD, 21201 USA,University of Maryland Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD, 21201 USA
| | - Junfang Wu
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland School of Medicine, Baltimore, MD 21201, USA; University of Maryland Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD 21201, USA.
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11
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Van Sandt RL, Welsh CJ, Jeffery ND, Young CR, McCreedy DA, Wright GA, Boudreau CE, Levine GJ, Levine JM. Circulating neutrophil activation in dogs with naturally occurring spinal cord injury secondary to intervertebral disk herniation. Am J Vet Res 2022; 83:324-330. [DOI: 10.2460/ajvr.21.05.0073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
OBJECTIVE
To investigate the time course of circulating neutrophil priming and activity in dogs with spinal cord injury secondary to intervertebral disk herniation that undergo decompressive surgery.
ANIMALS
9 dogs with spinal cord injury and 9 healthy dogs (controls).
PROCEDURES
For dogs with spinal cord injury, blood samples were collected on the day of hospital admission and 3, 7, 30, and 90 days after injury and decompressive surgery. A single blood sample was collected from the control dogs. Flow cytometry analysis was performed on isolated neutrophils incubated with antibody against CD11b and nonfluorescent dihydrorhodamine 123, which was converted to fluorescent rhodamine 123 to measure oxidative burst activity.
RESULTS
Expression of CD11b was increased in dogs with spinal cord injury 3 days after injury and decompressive surgery, relative to day 7 expression. Neutrophils expressed high oxidative burst activity both 3 and 7 days after injury and decompressive surgery, compared with activity in healthy dogs.
CLINICAL RELEVANCE
For dogs with spinal cord injury, high CD11b expression 3 days after injury and decompressive surgery was consistent with findings for rodents with experimentally induced spinal cord injury. However, the high oxidative burst activity 3 and 7 days after injury and decompressive surgery was not consistent with data from other species, and additional studies on inflammatory events in dogs with naturally occurring spinal cord injury are needed.
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Affiliation(s)
- Rae L. Van Sandt
- 1Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
- 2Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - C. Jane Welsh
- 2Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - Nick D. Jeffery
- 1Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - Colin R. Young
- 2Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - Dylan A. McCreedy
- 3Department of Biology, College of Science, Texas A&M University, College Station, TX
| | - Gus A. Wright
- 4Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
- 5Flow Cytometry Facility, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - C. Elizabeth Boudreau
- 1Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - Gwendolyn J. Levine
- 4Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - Jonathan M. Levine
- 1Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
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12
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Baine RE, Johnston DT, Strain MM, Henwood MK, Davis JA, Reynolds JA, Giles ED, Grau JW. Noxious Stimulation Induces Acute Hemorrhage and Impairs Long-Term Recovery after Spinal Cord Injury (SCI) in Female Rats: Evidence Estrous Cycle May Have a Modulatory Effect. Neurotrauma Rep 2022; 3:70-86. [PMID: 35112109 PMCID: PMC8804264 DOI: 10.1089/neur.2021.0055] [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] [Indexed: 11/16/2022] Open
Abstract
Spinal cord injuries (SCIs) are often the result of traumatic accidents, which also produce multiple other injuries (polytrauma). Nociceptive input from associated injuries has been shown to significantly impair recovery post-SCI. Historically, work in our laboratory has focused exclusively on male animals; however, increasing incidence of SCI in females requires research to determine whether pain (nociceptive) input poses the same risk to their recovery. Some animal studies have shown that females demonstrate greater tissue preservation and better locomotor recovery post-SCI. Given this, we examined the effect of sex on SCI recovery in two pain models—intermittent electrical stimulation (shock) to the tail or capsaicin injection to the hindpaw. Female rats received a lower thoracic contusion injury and were exposed to noxious stimulation the next day. The acute effect of noxious input on cardiovascular function, locomotor performance, and hemorrhage were assessed. Treatment with capsaicin or noxious electrical stimulation disrupted locomotor performance, increased blood pressure, and disrupted stepping. Additional experiments examined the long-term consequences of noxious input, demonstrating that both noxious electrical stimulation and capsaicin impair long-term recovery in female rats. Interestingly, injury had a greater effect on behavioral performance when progesterone and estrogen were low (metestrus). Conversely, nociceptive input led to a greater disruption in locomotor performance and produced a greater rise in blood pressure in animals injured during estrus.
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Affiliation(s)
- Rachel E. Baine
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, Texas, USA
| | - David T. Johnston
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, Texas, USA
| | - Misty M. Strain
- Department of Cellular and Integrative Physiology, University of Texas Health Science, San Antonio, Texas, USA
| | - Melissa K. Henwood
- Department of Neuroscience, Cell Biology, Anatomy, University of Texas Medical Branch, Galveston, Texas, USA
| | - Jacob A. Davis
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, Texas, USA
| | - Joshua A. Reynolds
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, Texas, USA
| | - Erin D. Giles
- Department of Nutrition, Texas A&M University, College Station, Texas, USA
| | - James W. Grau
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, Texas, USA
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13
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Stewart AN, Lowe JL, Glaser EP, Mott CA, Shahidehpour RK, McFarlane KE, Bailey WM, Zhang B, Gensel JC. Acute inflammatory profiles differ with sex and age after spinal cord injury. J Neuroinflammation 2021; 18:113. [PMID: 33985529 PMCID: PMC8120918 DOI: 10.1186/s12974-021-02161-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/29/2021] [Indexed: 01/05/2023] Open
Abstract
Background Sex and age are emerging as influential variables that affect spinal cord injury (SCI) recovery. Despite a changing demographic towards older age at the time of SCI, the effects of sex or age on inflammation remain to be elucidated. This study determined the sex- and age-dependency of the innate immune response acutely after SCI. Methods Male and female mice of ages 4- and 14-month-old received T9 contusion SCI and the proportion of microglia, monocyte-derived macrophages (MDM), and neutrophils surrounding the lesion were determined at 3- and 7-day post-injury (DPI) using flow cytometry. Cell counts of microglia and MDMs were obtained using immunohistochemistry to verify flow cytometry results at 3-DPI. Microglia and MDMs were separately isolated using fluorescence-activated cell sorting (FACS) at 3-day post-injury (DPI) to assess RNA expression of 27 genes associated with activation, redox, and debris metabolism/clearance. Results Flow cytometry revealed that being female and older at the time of injury significantly increased MDMs relative to other phagocytes, specifically increasing the ratio of MDMs to microglia at 3-DPI. Cell counts using immunohistochemistry revealed that male mice have more total microglia within SCI lesions that can account for a lower MDM/microglia ratio. With NanoString analyses of 27 genes, only 1 was differentially expressed between sexes in MDMs; specifically, complement protein C1qa was increased in males. No genes were affected by age in MDMs. Only 2 genes were differentially regulated in microglia between sexes after controlling for false discovery rate, specifically CYBB (NOX2) as a reactive oxygen species (ROS)-associated marker as well as MRC1 (CD206), a gene associated with reparative phenotypes. Both genes were increased in female microglia. No microglial genes were differentially regulated between ages. Differences between microglia and MDMs were found in 26 of 27 genes analyzed, all expressed higher in MDMs with three exceptions. Specifically, C1qa, cPLA2, and CD86 were expressed higher in microglia. Conclusions These findings indicate that inflammatory responses to SCI are sex-dependent at both the level of cellular recruitment and gene expression. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02161-8.
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Affiliation(s)
- Andrew N Stewart
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - John L Lowe
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA.,Science Honors Program of Georgetown College, Georgetown, KY, 40324, USA
| | - Ethan P Glaser
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Caitlin A Mott
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Ryan K Shahidehpour
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Katelyn E McFarlane
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - William M Bailey
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Bei Zhang
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA.,Present address: Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10021, USA
| | - John C Gensel
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA.
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14
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Kirshblum S, Snider B, Eren F, Guest J. Characterizing Natural Recovery after Traumatic Spinal Cord Injury. J Neurotrauma 2021; 38:1267-1284. [PMID: 33339474 PMCID: PMC8080912 DOI: 10.1089/neu.2020.7473] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The predominant tool used to predict outcomes after traumatic spinal cord injury (SCI) is the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), in association with the American Spinal Injury Association (ASIA) Impairment Scale (AIS). These measures have evolved based on analyses of large amounts of longitudinal neurological recovery data published in numerous separate studies. This article reviews and synthesizes published data on neurological recovery from multiple sources, only utilizing data in which the sacral sparing definition was applied for determination of completeness. Conversion from a complete to incomplete injury is more common in tetraplegia than paraplegia. The majority of AIS conversion and motor recovery occurs within the first 6-9 months, with the most rapid rate of motor recovery occurring in the first three months after injury. Motor score changes, as well as recovery of motor levels, are described with the initial strength of muscles as well as the levels of the motor zone of partial preservation influencing the prognosis. Total motor recovery is greater for patients with initial AIS B than AIS A, and greater after initial AIS C than with motor complete injuries. Older age has a negative impact on neurological and functional recovery after SCI; however, the specific age (whether >50 or >65 years) and underlying reasons for this impact are unclear. Penetrating injury is more likely to lead to a classification of a neurological complete injury compared with blunt trauma and reduces the likelihood of AIS conversion at one year. There are insufficient data to support gender having a major effect on neurological recovery after SCI.
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Affiliation(s)
- Steven Kirshblum
- Kessler Institute for Rehabilitation, West Orange, New Jersy, USA
- Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
- Kessler Foundation, West Orange, New Jersey, USA
| | - Brittany Snider
- Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, Minnesota, USA
| | - Fatma Eren
- Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
- Kessler Foundation, West Orange, New Jersey, USA
| | - James Guest
- Neurological Surgery, Miller School of Medicine, Miami, Florida, USA
- The Miami Project to Cure Paralysis, Miami, Florida, USA
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15
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Chen JY, Fu EJ, Patel PR, Hostetler AJ, Sawan HA, Moss KA, Hocevar SE, Anderson AJ, Chestek CA, Shea LD. Lentiviral Interleukin-10 Gene Therapy Preserves Fine Motor Circuitry and Function After a Cervical Spinal Cord Injury in Male and Female Mice. Neurotherapeutics 2021; 18:503-514. [PMID: 33051853 PMCID: PMC8116384 DOI: 10.1007/s13311-020-00946-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2020] [Indexed: 12/16/2022] Open
Abstract
In mammals, spinal cord injuries often result in muscle paralysis through the apoptosis of lower motor neurons and denervation of neuromuscular junctions. Previous research shows that the inflammatory response to a spinal cord injury can cause additional tissue damage after the initial trauma. To modulate this inflammatory response, we delivered lentiviral anti-inflammatory interleukin-10, via loading onto an implantable biomaterial scaffold, into a left-sided hemisection at the C5 vertebra in mice. We hypothesized that improved behavioral outcomes associated with anti-inflammatory treatment are due to the sparing of fine motor circuit components. We examined behavioral recovery using a ladder beam, tissue sparing using histology, and electromyogram recordings using intraspinal optogenetic stimulation at 2 weeks post-injury. Ladder beam analysis shows interleukin-10 treatment results in significant improvement of behavioral recovery at 2 and 12 weeks post-injury when compared to mice treated with a control virus. Histology shows interleukin-10 results in greater numbers of lower motor neurons, axons, and muscle innervation at 2 weeks post-injury. Furthermore, electromyogram recordings suggest that interleukin-10-treated animals have signal-to-noise ratios and peak-to-peak amplitudes more similar to that of uninjured controls than to that of control injured animals at 2 weeks post-injury. These data show that gene therapy using anti-inflammatory interleukin-10 can significantly reduce tissue damage and subsequent motor deficits after a spinal cord injury. Together, these results suggest that early modulation of the injury response can preserve muscle function with long-lasting benefits.
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Affiliation(s)
- Jessica Y Chen
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Emily J Fu
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
| | - Paras R Patel
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
| | - Alexander J Hostetler
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
| | - Hasan A Sawan
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
| | - Kayla A Moss
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
| | - Sarah E Hocevar
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Aileen J Anderson
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Cynthia A Chestek
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109, USA
- Robotics Program, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Lonnie D Shea
- Department of Biomedical Engineering, College of Engineering, University of Michigan, 2200 Bonisteel Boulevard, 1119 Carl A Gerstacker Building, Ann Arbor, MI, 48109, USA.
- Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
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16
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Gonzalez-Ruiz C, Cordero-Anguiano P, Morales-Guadarrama A, Mondragón-Lozano R, Sánchez-Torres S, Salgado-Ceballos H, Villarreal F, Meaney E, Ceballos G, Nájera N. (-)-Epicatechin reduces muscle waste after complete spinal cord transection in a murine model: role of ubiquitin-proteasome system. Mol Biol Rep 2020; 47:8975-8985. [PMID: 33151476 DOI: 10.1007/s11033-020-05954-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/28/2020] [Indexed: 12/17/2022]
Abstract
The skeletal muscle mass reduces 30-60% after spinal cord injury, this is mostly due to protein degradation through ubiquitin-proteasome system. In this work, we propose that the flavanol (-)-epicatechin, due its widespread biological effects on muscle health, can prevent muscle mass decrease after spinal cord injury. Thirty-six female Long Evans rats were randomized into 5 groups: (1) Spinal cord injury 7 days, (2) Spinal cord injury + (-)-epicatechin 7 days, (3) Spinal cord injury 30 days, (4) Spinal cord injury + (-)-epicatechin 30 days and (5) Sham (Only laminectomy). Hind limb perimeter, muscle cross section area, fiber cross section area and ubiquitin-proteasome system protein expression together with total protein ubiquitination were assessed. At 30 days Spinal cord injury group lost 49.52 ± 2.023% of muscle cross section area (-)-epicatechin treated group lost only 24.28 ± 15.45% being a significant difference. Ubiquitin-proteasome markers showed significant changes. FOXO1a increased in spinal cord injury group vs Sham (-)-epicatechin reduced this increase. In spinal cord injury group MAFbx increased significantly vs Sham but decrease in (-)-epicatechin treatment group at 30 days. At 7 and 30 days MuRF1 increased in the spinal cord injury and decreased in the (-)-epicatechin group. The global protein ubiquitination increases after spinal cord injury, epicatechin treatment induce a significant decrease in protein ubiquitination. These results suggest that (-)-epicatechin reduces the muscle waste after spinal cord injury through down regulation of the ubiquitin-proteasome system.
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Affiliation(s)
- Cristian Gonzalez-Ruiz
- Laboratorio de Investigación Integral Cardiometabólica, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico, Mexico
| | - Paola Cordero-Anguiano
- Laboratorio de Investigación Integral Cardiometabólica, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico, Mexico
| | - Axayacatl Morales-Guadarrama
- Centro Nacional de Investigación en Imagenología e Instrumentación Médica, Departamento de Ingeniería Eléctrica, Universidad Autónoma Metropolitana Iztapalapa, Mexico, Mexico
| | - Rodrigo Mondragón-Lozano
- Consejo Nacional de Ciencia y Tecnología, Unidad de Investigación Médica en Enfermedades Neurológicas, Hospital de Especialidades Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico, Mexico
| | - Stephanie Sánchez-Torres
- División de Ciencias Biológicas y de la Salud, Posgrado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico, Mexico
| | - Hermelinda Salgado-Ceballos
- Unidad de Investigación Médica en Enfermedades Neurológicas, Hospital de Especialidades Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico, Mexico
| | | | - Eduardo Meaney
- Laboratorio de Investigación Integral Cardiometabólica, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico, Mexico
| | - Guillermo Ceballos
- Laboratorio de Investigación Integral Cardiometabólica, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico, Mexico.
| | - Nayelli Nájera
- Laboratorio de Investigación Integral Cardiometabólica, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico, Mexico.
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17
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Stewart AN, MacLean SM, Stromberg AJ, Whelan JP, Bailey WM, Gensel JC, Wilson ME. Considerations for Studying Sex as a Biological Variable in Spinal Cord Injury. Front Neurol 2020; 11:802. [PMID: 32849242 PMCID: PMC7419700 DOI: 10.3389/fneur.2020.00802] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 06/26/2020] [Indexed: 12/13/2022] Open
Abstract
In response to NIH initiatives to investigate sex as a biological variable in preclinical animal studies, researchers have increased their focus on male and female differences in neurotrauma. Inclusion of both sexes when modeling neurotrauma is leading to the identification of novel areas for therapeutic and scientific exploitation. Here, we review the organizational and activational effects of sex hormones on recovery from injury and how these changes impact the long-term health of spinal cord injury (SCI) patients. When determining how sex affects SCI it remains imperative to expand outcomes beyond locomotor recovery and consider other complications plaguing the quality of life of patients with SCI. Interestingly, the SCI field predominately utilizes female rodents for basic science research which contrasts most other male-biased research fields. We discuss the unique caveats this creates to the translatability of preclinical research in the SCI field. We also review current clinical and preclinical data examining sex as biological variable in SCI. Further, we report how technical considerations such as housing, size, care management, and age, confound the interpretation of sex-specific effects in animal studies of SCI. We have uncovered novel findings regarding how age differentially affects mortality and injury-induced anemia in males and females after SCI, and further identified estrus cycle dysfunction in mice after injury. Emerging concepts underlying sexually dimorphic responses to therapy are also discussed. Through a combination of literature review and primary research observations we present a practical guide for considering and incorporating sex as biological variable in preclinical neurotrauma studies.
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Affiliation(s)
- Andrew N Stewart
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Steven M MacLean
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Arnold J Stromberg
- Department of Statistics, College of Arts and Sciences, University of Kentucky, Lexington, KY, United States
| | - Jessica P Whelan
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - William M Bailey
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - John C Gensel
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Melinda E Wilson
- Department of Physiology, University of Kentucky, Lexington, KY, United States
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18
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McFarlane K, Otto TE, Bailey WM, Veldhorst AK, Donahue RR, Taylor BK, Gensel JC. Effect of Sex on Motor Function, Lesion Size, and Neuropathic Pain after Contusion Spinal Cord Injury in Mice. J Neurotrauma 2020; 37:1983-1990. [PMID: 32597310 PMCID: PMC7470221 DOI: 10.1089/neu.2019.6931] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Spinal cord injury (SCI) causes neurodegeneration, impairs locomotor function, and impacts the quality of life particularly in those individuals in whom neuropathic pain develops. Whether the time course of neurodegeneration, locomotor impairment, or neuropathic pain varies with sex, however, remains understudied. Therefore, the objective of this study in male and female C57BL/6 mice was to evaluate the following outcomes for six weeks after a 75-kdyn thoracic contusion SCI: locomotor function using the Basso Mouse Scale (BMS); spinal cord tissue sparing and rostral-caudal lesion length; and mechanical allodynia and heat hyperalgesia using hindpaw application of Von Frey filaments or radiant heat stimuli, respectively. Although motor function was largely similar between sexes, all of the males, but only half of the females, recovered plantar stepping. Rostral-caudal lesion length was shorter in females than in males. Mechanical allodynia and heat hyperalgesia after SCI developed in all animals, regardless of sex; there were no differences in pain outcomes between sexes. We conclude that contusion SCI yields subtle sex differences in mice depending on the outcome measure but no significant differences in behavioral signs of neuropathic pain.
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Affiliation(s)
- Katelyn McFarlane
- Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Taylor E Otto
- Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - William M Bailey
- Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Amy K Veldhorst
- Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Renée R Donahue
- Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Bradley K Taylor
- Department of Anesthesia and Perioperative Medicine, Pittsburgh Center for Pain Research, and Pittsburgh Project to End Opioid Misuse, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - John C Gensel
- Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
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19
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Melo MC, Macedo DR, Soares AB. Divergent Findings in Brain Reorganization After Spinal Cord Injury: A Review. J Neuroimaging 2020; 30:410-427. [PMID: 32418286 DOI: 10.1111/jon.12711] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/02/2020] [Accepted: 03/24/2020] [Indexed: 12/12/2022] Open
Abstract
Spinal cord injury (SCI) leads to a general lack of sensory and motor functions below the level of injury and may promote deafferentation-induced brain reorganization. Functional magnetic resonance imaging (fMRI) has been established as an essential tool in neuroscience research and can precisely map the spatiotemporal distribution of brain activity. Task-based fMRI experiments associated with the tongue, upper limbs, or lower limbs have been used as the primary paradigms to study brain reorganization following SCI. A review of the current literature on the subject shows one common trait: while most articles agree that brain networks are usually preserved after SCI, and that is not the case as some articles describe possible alterations in brain activation after the lesion. There is no consensus if those alterations indeed occur. In articles that show alterations, there is no agreement if they are transient or permanent. Besides, there is no consensus on which areas are most prone to activation changes, or on the intensity and direction (increase vs. decrease) of those possible changes. In this article, we present a critical review of the literature and trace possible reasons for those contradictory findings on brain reorganization following SCI. fMRI studies based on the ankle dorsiflexion, upper-limb, and tongue paradigms are used as case studies for the analyses.
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Affiliation(s)
- Mariana Cardoso Melo
- Biomedical Engineering Lab, Federal University of Uberlandia, Uberlandia, Minas Gerais, Brazil
| | - Dhainner Rocha Macedo
- Biomedical Engineering Lab, Federal University of Uberlandia, Uberlandia, Minas Gerais, Brazil
| | - Alcimar Barbosa Soares
- Biomedical Engineering Lab, Federal University of Uberlandia, Uberlandia, Minas Gerais, Brazil
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20
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Ghnenis AB, Burns DT, Osimanjiang W, He G, Bushman JS. A Long-Term Pilot Study on Sex and Spinal Cord Injury Shows Sexual Dimorphism in Functional Recovery and Cardio-Metabolic Responses. Sci Rep 2020; 10:2762. [PMID: 32066802 PMCID: PMC7026076 DOI: 10.1038/s41598-020-59628-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 01/28/2020] [Indexed: 12/25/2022] Open
Abstract
More than a quarter of a million individuals in the US live with spinal cord injury (SCI). SCI disrupts neural circuitry to vital organs in the body. Despite severe incidences of long-term peripheral complications from SCI, the cardio-metabolic consequences and divergences in sex-related responses are not well described. We examined the effects of SCI on functional recovery, cardiac structure and function, body composition, and glucose metabolism on adult female and male Sprague Dawley (SD) rats. SCI was induced at T10 via contusion. Measured outcomes include behavioral assessment, body weight, dual-energy X-ray absorptiometry (DEXA) for body composition, echocardiography for cardiac structure and function, intraperitoneal glucose tolerance test (IPGTT) for glucose metabolism, insulin tolerance test (ITT), and histology of cardiac structure at the endpoint. There was a decrease in body fat percentage in both sexes, with SCI females disproportionately affected in percent body fat change. Left ventricular internal diameter during systole (LVIDs) was decreased in SCI females more than in SCI males. No significant differences in glucose metabolism were observed up to 20 weeks post-injury (PI). These data show significant cardio-metabolic differences as a consequence of SCI and, furthermore, that sex is an underlying factor in these differences.
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Affiliation(s)
- Adel B Ghnenis
- University of Wyoming School of Pharmacy, 1000 East University Avenue, Department 3375, Laramie, WY, 82071, USA
| | - Daniel T Burns
- University of Wyoming School of Pharmacy, 1000 East University Avenue, Department 3375, Laramie, WY, 82071, USA
| | - Wupu Osimanjiang
- University of Wyoming School of Pharmacy, 1000 East University Avenue, Department 3375, Laramie, WY, 82071, USA
| | - Guanglong He
- University of Wyoming School of Pharmacy, 1000 East University Avenue, Department 3375, Laramie, WY, 82071, USA
| | - Jared S Bushman
- University of Wyoming School of Pharmacy, 1000 East University Avenue, Department 3375, Laramie, WY, 82071, USA.
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Kim T, Chelluboina B, Chokkalla AK, Vemuganti R. Age and sex differences in the pathophysiology of acute CNS injury. Neurochem Int 2019; 127:22-28. [PMID: 30654116 PMCID: PMC6579702 DOI: 10.1016/j.neuint.2019.01.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/11/2019] [Indexed: 12/21/2022]
Abstract
Despite the immeasurable burden on patients and families, no effective therapies to protect the CNS after an acute injury are available yet. Furthermore, the underlying mechanisms that promote neuronal death and functional deficits after injury remain to be poorly understood. The prevalence, age of onset, pathophysiology, and symptomatology of many CNS insults differ significantly between males and females. In the case of stroke, younger males tend to show a higher risk than younger females, while this trend reverses with age. Accumulating evidence from preclinical studies have shown that sex hormones play a crucial role in providing neuroprotection following ischemic stroke and other acute CNS injuries. Estrogen, in particular, exerts a neuroprotective effect by modulating the immune responses after injury. In addition, there exists a sexual dimorphism in cell death pathways between males and females that are independent of hormones. Meanwhile, recent studies suggest that microRNAs are critically involved in the sex-specific mechanisms of cell death. This review discusses the current knowledge on the contribution of sex and age to outcome after stroke. Implication of the interplay between these two factors on other CNS injuries (spinal cord injury and traumatic brain injury) from the experimental evidence were also discussed.
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Affiliation(s)
- TaeHee Kim
- Department of Neurological Surgery, University of Wisconsin, Madison, WI, USA
| | - Bharath Chelluboina
- Department of Neurological Surgery, University of Wisconsin, Madison, WI, USA
| | - Anil K Chokkalla
- Department of Neurological Surgery, University of Wisconsin, Madison, WI, USA; Cellular and Molecular Pathology Program, University of Wisconsin, Madison, WI, USA
| | - Raghu Vemuganti
- Department of Neurological Surgery, University of Wisconsin, Madison, WI, USA; Cellular and Molecular Pathology Program, University of Wisconsin, Madison, WI, USA; William S. Middleton Veterans Administration Hospital, Madison, WI, USA.
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22
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Walker CL, Fry CME, Wang J, Du X, Zuzzio K, Liu NK, Walker MJ, Xu XM. Functional and Histological Gender Comparison of Age-Matched Rats after Moderate Thoracic Contusive Spinal Cord Injury. J Neurotrauma 2019; 36:1974-1984. [PMID: 30489213 DOI: 10.1089/neu.2018.6233] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Spinal cord injury (SCI) afflicts hundreds of thousands of Americans, and most SCI (∼80%) occurs in males. In experimental animal models, however, many studies used females. Funding agencies like the National Institutes of Health recommend that new proposed studies should include both genders due to variations in gender response to injuries, diseases, and treatments. However, cost and considerations for some animal models, such as SCI, affect investigators in adapting to this recommendation. Research has increased comparing gender effects in various disease and injury models, including SCI. However, most studies use weight-matched animals, which poses issues in comparing results and outcomes. The present study compared histologic and functional outcomes between age-matched male and female Sprague-Dawley rats in a moderate thoracic contusion SCI model. Cresyl violet and eosin staining showed no significant differences in lesion volume between genders after 9 weeks post-SCI (p > 0.05). Luxol fast blue-stained spared myelin was similar between genders, although slightly greater (∼6%) in spared myelin, compared with cord volume (p = 0.044). Glial reactivity and macrophage labeling in the lesion area was comparable between genders, as well. Basso, Beattie, Bresnahan (BBB) functional scores were not significantly different between genders, and Hargreaves thermal hyperalgesia and Gridwalk sensorimotor analyses also were similar between genders, compared with uninjured gender controls. Analysis of covariance showed weight did not influence functional recovery as assessed through BBB (p = 0.65) or Gridwalk assessment (p = 0.63) in this study. In conclusion, our findings suggest age-matched male and female rats recover similarly in a common clinically relevant SCI model.
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Affiliation(s)
- Chandler L Walker
- 1 Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana.,3 Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana.,5 Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, Indianapolis, Indiana
| | - Colin M E Fry
- 1 Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana.,2 Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana.,4 Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Junmei Wang
- 5 Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, Indianapolis, Indiana
| | - Xiaolong Du
- 1 Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana
| | - Kirstin Zuzzio
- 5 Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, Indianapolis, Indiana
| | - Nai-Kui Liu
- 1 Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana.,2 Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana.,4 Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Melissa J Walker
- 1 Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana.,2 Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Xiao-Ming Xu
- 1 Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana.,2 Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana.,3 Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana.,4 Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
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23
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Sengelaub DR, Xu XM. Protective effects of gonadal hormones on spinal motoneurons following spinal cord injury. Neural Regen Res 2018; 13:971-976. [PMID: 29926818 PMCID: PMC6022470 DOI: 10.4103/1673-5374.233434] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/19/2018] [Indexed: 11/29/2022] Open
Abstract
Spinal cord injury (SCI) results in lesions that destroy tissue and disrupt spinal tracts, producing deficits in locomotor and autonomic function. The majority of treatment strategies after SCI have concentrated on the damaged spinal cord, for example working to reduce lesion size or spread, or encouraging regrowth of severed descending axonal projections through the lesion, hoping to re-establish synaptic connectivity with caudal targets. In our work, we have focused on a novel target for treatment after SCI, surviving spinal motoneurons and their target musculature, with the hope of developing effective treatments to preserve or restore lost function following SCI. We previously demonstrated that motoneurons, and the muscles they innervate, show pronounced atrophy after SCI. Importantly, SCI-induced atrophy of motoneuron dendrites can be attenuated by treatment with gonadal hormones, testosterone and its active metabolites, estradiol and dihydrotestosterone. Similarly, SCI-induced reductions in muscle fiber cross-sectional areas can be prevented by treatment with androgens. Together, these findings suggest that regressive changes in motoneuron and muscle morphology seen after SCI can be ameliorated by treatment with gonadal hormones, further supporting a role for steroid hormones as neurotherapeutic agents in the injured nervous system.
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Affiliation(s)
- Dale R. Sengelaub
- Psychological and Brain Sciences, Indiana University, Bloomington, IN, USA
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
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24
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Sengelaub DR, Han Q, Liu NK, Maczuga MA, Szalavari V, Valencia SA, Xu XM. Protective Effects of Estradiol and Dihydrotestosterone following Spinal Cord Injury. J Neurotrauma 2018; 35:825-841. [PMID: 29132243 PMCID: PMC5863086 DOI: 10.1089/neu.2017.5329] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Spinal cord injury (SCI) results in lesions that destroy tissue and disrupt spinal tracts, producing deficits in locomotor and autonomic function. We previously demonstrated that motoneurons and the muscles they innervate show pronounced atrophy after SCI, and these changes are prevented by treatment with testosterone. Here, we assessed whether the testosterone active metabolites estradiol and dihydrotestosterone have similar protective effects after SCI. Young adult female rats received either sham or T9 spinal cord contusion injuries and were treated with estradiol, dihydrotestosterone, both, or nothing via Silastic capsules. Basso-Beattie-Bresnahan locomotor testing was performed weekly and voiding behavior was assessed at 3 weeks post-injury. Four weeks after SCI, lesion volume and tissue sparing, quadriceps muscle fiber cross-sectional area, and motoneuron dendritic morphology were assessed. Spontaneous locomotor behavior improved after SCI, but hormone treatments had no effect. Voiding behavior was disrupted after SCI, but was significantly improved by treatment with either estradiol or dihydrotestosterone; combined treatment was maximally effective. Treatment with estradiol reduced lesion volume, but dihydrotestosterone alone and estradiol combined with dihydrotestosterone were ineffective. SCI-induced decreases in motoneuron dendritic length were attenuated by all hormone treatments. SCI-induced reductions in muscle fiber cross-sectional areas were prevented by treatment with either dihydrotestosterone or estradiol combined with dihydrotestosterone, but estradiol treatment was ineffective. These findings suggest that deficits in micturition and regressive changes in motoneuron and muscle morphology seen after SCI are ameliorated by treatment with estradiol or dihydrotestosterone, further supporting a role for steroid hormones as neurotherapeutic agents in the injured nervous system.
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Affiliation(s)
- Dale R. Sengelaub
- Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | - Qi Han
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Nai-Kui Liu
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Melissa A. Maczuga
- Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | - Violetta Szalavari
- Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | | | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Indiana University School of Medicine, Indianapolis, Indiana
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25
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Colón JM, González PA, Cajigas Á, Maldonado WI, Torrado AI, Santiago JM, Salgado IK, Miranda JD. Continuous tamoxifen delivery improves locomotor recovery 6h after spinal cord injury by neuronal and glial mechanisms in male rats. Exp Neurol 2018; 299:109-121. [PMID: 29037533 PMCID: PMC5723542 DOI: 10.1016/j.expneurol.2017.10.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022]
Abstract
No treatment is available for patients with spinal cord injury (SCI). Patients often arrive to the hospital hours after SCI suggesting the need of a therapy that can be used on a clinically relevant window. Previous studies showed that Tamoxifen (TAM) treatment 24h after SCI benefits locomotor recovery in female rats. Tamoxifen exerts beneficial effects in male and female rodents but a gap of knowledge exists on: the therapeutic window of TAM, the spatio-temporal mechanisms activated and if this response is sexually dimorphic. We hypothesized that TAM will favor locomotor recovery when administered up-to 24h after SCI in male Sprague-Dawley rats. Rats received a thoracic (T10) contusion using the MACSIS impactor followed by placebo or TAM (15mg/21days) pellets in a therapeutic window of 0, 6, 12, or 24h. Animals were sacrificed at 2, 7, 14, 28 or 35days post injury (DPI) to study the molecular and cellular changes in the acute and chronic stages. Immediate or delayed therapy (t=6h) improved locomotor function, increased white matter spared tissue, and neuronal survival. TAM reduced reactive gliosis during chronic stages and increased the expression of Olig-2. A significant difference was observed in estrogen receptor alpha between male and female rodents from 2 to 28 DPI suggesting a sexually dimorphic characteristic that could be related to the behavioral differences observed in the therapeutic window of TAM. This study supports the use of TAM in the SCI setting due to its neuroprotective effects but with a significant sexually dimorphic therapeutic window.
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Affiliation(s)
- Jennifer M Colón
- University of Puerto Rico Medical Sciences Campus, Department of Physiology, San Juan, PR 00936, USA.
| | - Pablo A González
- University of Puerto Rico Medical Sciences Campus, Department of Physiology, San Juan, PR 00936, USA.
| | - Ámbar Cajigas
- University of Puerto Rico Medical Sciences Campus, Department of Physiology, San Juan, PR 00936, USA.
| | - Wanda I Maldonado
- University of Puerto Rico Carolina Campus, Neuroregeneration Division, Neuroscience Research Laboratory, Natural Sciences Department, Carolina, PR 00984, USA.
| | - Aranza I Torrado
- University of Puerto Rico Medical Sciences Campus, Department of Physiology, San Juan, PR 00936, USA.
| | - José M Santiago
- University of Puerto Rico Carolina Campus, Neuroregeneration Division, Neuroscience Research Laboratory, Natural Sciences Department, Carolina, PR 00984, USA.
| | - Iris K Salgado
- University of Puerto Rico Medical Sciences Campus, Department of Physiology, San Juan, PR 00936, USA.
| | - Jorge D Miranda
- University of Puerto Rico Medical Sciences Campus, Department of Physiology, San Juan, PR 00936, USA.
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26
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Colón JM, Miranda JD. Tamoxifen: an FDA approved drug with neuroprotective effects for spinal cord injury recovery. Neural Regen Res 2016; 11:1208-11. [PMID: 27651756 PMCID: PMC5020807 DOI: 10.4103/1673-5374.189164] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Spinal cord injury (SCI) is a condition without a cure, affecting sensory and/or motor functions. The physical trauma to the spinal cord initiates a cascade of molecular and cellular events that generates a non-permissive environment for cell survival and axonal regeneration. Among these complex set of events are damage of the blood-brain barrier, edema formation, inflammation, oxidative stress, demyelination, reactive gliosis and apoptosis. The multiple events activated after SCI require a multi-active drug that could target most of these events and produce a permissive environment for cell survival, regeneration, vascular reorganization and synaptic formation. Tamoxifen, a selective estrogen receptor modulator, is an FDA approved drug with several neuroprotective properties that should be considered for the treatment of this devastating condition. Various investigators using different animal models and injury parameters have demonstrated the beneficial effects of this drug to improve functional locomotor recovery after SCI. Results suggest that the mechanism of action of Tamoxifen administration is to modulate anti-oxidant, anti-inflammatory and anti-gliotic responses. A gap of knowledge exists regarding the sex differences in response to Tamoxifen and the therapeutic window available to administer this treatment. In addition, the effects of Tamoxifen in axonal outgrowth or synapse formation needs to be investigated. This review will address some of the mechanisms activated by Tamoxifen after SCI and the results recently published by investigators in the field.
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Affiliation(s)
- Jennifer M Colón
- Department of Physiology, School of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, PR, USA
| | - Jorge D Miranda
- Department of Physiology, School of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, PR, USA
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27
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Arbo BD, Benetti F, Ribeiro MF. Astrocytes as a target for neuroprotection: Modulation by progesterone and dehydroepiandrosterone. Prog Neurobiol 2016; 144:27-47. [DOI: 10.1016/j.pneurobio.2016.03.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 01/14/2016] [Accepted: 03/14/2016] [Indexed: 01/19/2023]
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28
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Use of the CatWalk Gait Device to Assess Differences in Locomotion between Genders in Rats Inherently and following Spinal Cord Injury. ACTA ACUST UNITED AC 2016. [DOI: 10.1155/2016/6276348] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A possible cause of differences in recovery after spinal cord injury (SCI) is gender. The effect of gender on locomotor recovery following SCI, however, remains controversial and has produced conflicting results regarding gender’s impact on outcome. A significant shortcoming of previous studies was small sample size. The current work tested what, if any, significant differences existed between genders after SCI with CatWalk Gait Analysis that uses an automated device to measure the foot placement and gait of animals as they voluntarily cross an illuminated glass runway. We hypothesized that, by employing larger sample sizes in a reproducible and clinically relevant contusive SCI paradigm, subtle distinctions in locomotor recovery between sexes, if they exist, would be elucidated. During 13 weeks of functional assessment after SCI, a number of CatWalk parameters, including swing, single stance, and stride length, were significantly affected by gender only as identified by use of ANCOVA analysis, considering age, weight, and baseline performance as covariates. We report here our findings for 197 parameters that were assessed before and after SCI. Evaluating differences in locomotor recovery between sexes after SCI could point to a gender-related advantage and provide novel directions for the development of future therapeutics.
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29
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Datto JP, Yang J, Dietrich WD, Pearse DD. Does being female provide a neuroprotective advantage following spinal cord injury? Neural Regen Res 2015; 10:1533-6. [PMID: 26692831 PMCID: PMC4660727 DOI: 10.4103/1673-5374.165213] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
It has been controversial whether gender has any effect on recovery following spinal cord injury (SCI). Past experimental and clinical research aimed at addressing this subject has led to constrasting findings on whether females hold any advantage in locomotor recovery. Additionally, for studies supporting the notion of a female gender related advantage, a definite cause has not been explained. In a recent study, using large sample sizes for comparative male and female spinal cord injury cohorts, we reported that a significant gender advantage favoring females existed in both tissue preservation and functional recovery after taking into consideration discrepancies in age and weight of the animals across sexes. Prior animal research frequently used sample sizes that were too small to determine significance with certainty and also did not account for two other factors that influence locomotor performance: age and weight. Our finding is important in light of controversy surrounding the effect of gender on outcome and the fact that SCI affects more than ten thousand new individuals annually, a population that is disproportionately male. By deepening our understanding of why a gender advantage exists, potential new therapeutics can be designed to improve recovery for the male population following the initial trauma or putatively augment the neuroprotective privilege in females for enhanced outcomes.
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Affiliation(s)
- Jeffrey P Datto
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jackie Yang
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA
| | - W Dalton Dietrich
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA ; The Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, USA ; The Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA ; The Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL, USA ; The Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL, USA ; The Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Damien D Pearse
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA ; The Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, USA ; The Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL, USA ; The Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL, USA
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30
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Lee JY, Choi HY, Na WH, Ju BG, Yune TY. 17β-estradiol inhibits MMP-9 and SUR1/TrpM4 expression and activation and thereby attenuates BSCB disruption/hemorrhage after spinal cord injury in male rats. Endocrinology 2015; 156:1838-50. [PMID: 25763638 DOI: 10.1210/en.2014-1832] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Blood-spinal cord barrier (BSCB) disruption and progressive hemorrhage after spinal cord injury (SCI) lead to secondary injury and the subsequent apoptosis and/or necrosis of neuron and glia, causing permanent neurological deficits. In this study, we examined the effect of 17β-estradiol (E2) on BSCB breakdown and hemorrhage as well as subsequent inflammation after SCI. After a moderate contusion injury at the 9th thoracic segment of spinal cord, E2 (300 μg/kg) was administered by iv injection immediately after SCI, and the same dose of E2 was then administered 6 and 24 hours after injury. Our data show that E2 attenuated BSCB permeability and hemorrhage and reduced the infiltration of neutrophils and macorphages after SCI. Consistent with this finding, the expression of inflammatory mediators was significantly reduced by E2. Furthermore, E2 treatment significantly inhibited the expression of sulfonylurea receptor 1 and transient receptor potential melastatin 4 after injury, which are known to mediate hemorrhage at an early stage after SCI. Moreover, the expression and activation of matrix metalloprotease-9 after injury, which is known to disrupt BSCB, and the degradation of tight junction proteins, such as zona occludens-1 and occludin, were significantly inhibited by E2 treatment. Furthermore, the protective effects of E2 on BSCB disruption and functional improvement were abolished by an estrogen receptor antagonist, ICI 182780 (3 mg/kg). Thus, our study provides evidence that the neuroprotective effect of E2 after SCI is, in part, mediated by inhibiting BSCB disruption and hemorrhage through the down-regulation of sulfonylurea receptor 1/transient receptor potential melastatin 4 and matrix metalloprotease-9, which is dependent on estrogen receptor.
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Affiliation(s)
- Jee Y Lee
- Age-Related and Brain Diseases Research Center (J.Y.L., H.Y.C., T.Y.Y.) and Department of Biochemistry and Molecular Biology (T.Y.Y.), School of Medicine, Kyung Hee University, Seoul, 130-701, Korea; and Department of Life Science (W.H.N., B.G.J.), Sogang University, Seoul 121-742, Korea
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31
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Datto JP, Bastidas JC, Miller NL, Shah AK, Arheart KL, Marcillo AE, Dietrich WD, Pearse DD. Female Rats Demonstrate Improved Locomotor Recovery and Greater Preservation of White and Gray Matter after Traumatic Spinal Cord Injury Compared to Males. J Neurotrauma 2015; 32:1146-57. [PMID: 25715192 DOI: 10.1089/neu.2014.3702] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The possibility of a gender-related difference in recovery after spinal cord injury (SCI) remains a controversial subject. Current empirical animal research lacks sizable test groups to definitively determine whether significant differences exist. Evaluating locomotor recovery variances between sexes following a precise, clinically relevant spinal cord contusion model can provide valuable insight into a possible gender-related advantage in outcome post-SCI. In the current study, we hypothesized that by employing larger sample sizes in a reproducible contusive SCI paradigm, subtle distinctions in locomotor recovery between sexes, if they exist, would be elucidated through a broad range of behavioral tests. During 13 weeks of functional assessment after a thoracic (T8) contusive SCI in rat, significant differences owing to gender existed for the Basso, Beattie, and Bresnahan score and CatWalk hindlimb swing, support four, and single stance analyses. Significant differences in locomotor performance were noticeable as early as 4 weeks post-SCI. Stereological tissue-volume analysis determined that females, more so than males, also exhibited greater volumes of preserved gray and white matter within the injured cord segment as well as more spared ventral white matter area at the center of the lesion. The stereological tissue analysis differences favoring females directly correlated with the female rats' greater functional improvement observed at endpoint.
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Affiliation(s)
- Jeffrey P Datto
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida
| | - Johana C Bastidas
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida
| | - Nicole L Miller
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida
| | - Anna K Shah
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida
| | - Kristopher L Arheart
- 2 The Departments of Public Health Sciences, University of Miami Miller School of Medicine , Miami, Florida
| | - Alexander E Marcillo
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida
| | - W Dalton Dietrich
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.,3 The Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida.,4 The Department of Cell Biology, University of Miami Miller School of Medicine , Miami, Florida.,5 The Department of Neurology, University of Miami Miller School of Medicine , Miami, Florida.,6 The Neuroscience Program, University of Miami Miller School of Medicine , Miami, Florida
| | - Damien D Pearse
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.,3 The Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida.,6 The Neuroscience Program, University of Miami Miller School of Medicine , Miami, Florida.,7 The Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine , Miami, Florida
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32
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Jones TB. Lymphocytes and autoimmunity after spinal cord injury. Exp Neurol 2014; 258:78-90. [PMID: 25017889 DOI: 10.1016/j.expneurol.2014.03.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 03/05/2014] [Accepted: 03/06/2014] [Indexed: 12/23/2022]
Abstract
Over the past 15 years an immense amount of data has accumulated regarding the infiltration and activation of lymphocytes in the traumatized spinal cord. Although the impact of the intraspinal accumulation of lymphocytes is still unclear, modulation of the adaptive immune response via active and passive vaccination is being evaluated for its preclinical efficacy in improving the outcome for spinal-injured individuals. The complexity of the interaction between the nervous and the immune systems is highlighted in the contradictions that appear in response to these modulations. Current evidence regarding augmentation and inhibition of the adaptive immune response to spinal cord injury is reviewed with an aim toward reconciling conflicting data and providing consensus issues that may be exploited in future therapies. Opportunities such an approach may provide are highlighted as well as the obstacles that must be overcome before such approaches can be translated into clinical trials.
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Affiliation(s)
- T Bucky Jones
- Department of Anatomy, Arizona College of Medicine, Midwestern University, Glendale, AZ, USA.
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Mosquera L, Colón JM, Santiago JM, Torrado AI, Meléndez M, Segarra AC, Rodríguez-Orengo JF, Miranda JD. Tamoxifen and estradiol improved locomotor function and increased spared tissue in rats after spinal cord injury: their antioxidant effect and role of estrogen receptor alpha. Brain Res 2014; 1561:11-22. [PMID: 24637260 DOI: 10.1016/j.brainres.2014.03.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/20/2014] [Accepted: 03/05/2014] [Indexed: 12/17/2022]
Abstract
17β-Estradiol is a multi-active steroid that imparts neuroprotection via diverse mechanisms of action. However, its role as a neuroprotective agent after spinal cord injury (SCI), or the involvement of the estrogen receptor-alpha (ER-α) in locomotor recovery, is still a subject of much debate. In this study, we evaluated the effects of estradiol and of Tamoxifen (an estrogen receptor mixed agonist/antagonist) on locomotor recovery following SCI. To control estradiol cyclical variability, ovariectomized female rats received empty or estradiol filled implants, prior to a moderate contusion to the spinal cord. Estradiol improved locomotor function at 7, 14, 21, and 28 days post injury (DPI), when compared to control groups (measured with the BBB open field test). This effect was ER-α mediated, because functional recovery was blocked with an ER-α antagonist. We also observed that ER-α was up-regulated after SCI. Long-term treatment (28 DPI) with estradiol and Tamoxifen reduced the extent of the lesion cavity, an effect also mediated by ER-α. The antioxidant effects of estradiol were seen acutely at 2 DPI but not at 28 DPI, and this acute effect was not receptor mediated. Rats treated with Tamoxifen recovered some locomotor activity at 21 and 28 DPI, which could be related to the antioxidant protection seen at these time points. These results show that estradiol improves functional outcome, and these protective effects are mediated by the ER-α dependent and independent-mechanisms. Tamoxifen׳s effects during late stages of SCI support the use of this drug as a long-term alternative treatment for this condition.
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Affiliation(s)
- Laurivette Mosquera
- Department of Physiology, University of Puerto Rico-School of Medicine, San Juan, PR 00936, USA
| | - Jennifer M Colón
- Department of Physiology, University of Puerto Rico-School of Medicine, San Juan, PR 00936, USA
| | - José M Santiago
- University of Puerto Rico Carolina Campus, Department of Natural Sciences, Carolina, PR 00984, USA
| | - Aranza I Torrado
- Department of Physiology, University of Puerto Rico-School of Medicine, San Juan, PR 00936, USA
| | | | - Annabell C Segarra
- Department of Physiology, University of Puerto Rico-School of Medicine, San Juan, PR 00936, USA
| | - José F Rodríguez-Orengo
- Department of Biochemistry, University of Puerto Rico-School of Medicine, San Juan, PR 00936, USA
| | - Jorge D Miranda
- Department of Physiology, University of Puerto Rico-School of Medicine, San Juan, PR 00936, USA.
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Elkabes S, Nicot AB. Sex steroids and neuroprotection in spinal cord injury: a review of preclinical investigations. Exp Neurol 2014; 259:28-37. [PMID: 24440641 DOI: 10.1016/j.expneurol.2014.01.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Revised: 12/25/2013] [Accepted: 01/04/2014] [Indexed: 11/30/2022]
Abstract
Spinal cord injury (SCI) is a debilitating condition that affects motor, sensory and autonomic functions. Subsequent to the first mechanical trauma, secondary events, which include inflammation and glial activation, exacerbate tissue damage and worsen functional deficits. Although these secondary injury mechanisms are amenable to therapeutic interventions, the efficacy of current approaches is inadequate. Further investigations are necessary to implement new therapies that can protect neural cells and attenuate some of the detrimental effects of inflammation while promoting regeneration. Studies on different animal models of SCI indicated that sex steroids, especially 17β-estradiol and progesterone, exert neuroprotective, anti-apoptotic and anti-inflammatory effects, ameliorate tissue sparing and improve functional deficits in SCI. As sex steroid receptors are expressed in a variety of cells including neurons, glia and immune system-related cells which infiltrate the injury epicenter, sex steroids could impact multiple processes simultaneously and in doing so, influence the outcomes of SCI. However, the translation of these pre-clinical findings into the clinical setting presents challenges such as the narrow therapeutic time window of sex steroid administration, the diversity of treatment regimens that have been employed in animal studies and the lack of sufficient information regarding the persistence of the effects in chronic SCI. The current review will summarize some of the major findings in this field and will discuss the challenges associated with the implementation of sex steroids as a promising treatment in human SCI.
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Affiliation(s)
- Stella Elkabes
- The Reynolds Family Spine Laboratory, Department of Neurological Surgery, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103, USA.
| | - Arnaud B Nicot
- UMR 1064, INSERM, Nantes, France; Faculté de Médecine, Université de Nantes, France; ITUN, CHU de Nantes, France
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Siriphorn A, Dunham KA, Chompoopong S, Floyd CL. Postinjury administration of 17β-estradiol induces protection in the gray and white matter with associated functional recovery after cervical spinal cord injury in male rats. J Comp Neurol 2013; 520:2630-46. [PMID: 22684936 DOI: 10.1002/cne.23056] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The majority of spinal cord injuries (SCIs) in the clinic occur at the lower cervical levels, resulting in both white and gray matter disruption. In contrast, most experimental models of SCI in rodents induce damage in the thoracic cord, resulting primarily in white matter disruption. To address this disparity, experimental cervical SCI models have been developed. Thus, we used a recently characterized model of cervical hemicontusion SCI in adult male rats to assess the potential therapeutic effect of post-SCI administration of 17β-estradiol. Rats received a hemicontusion at the level of the fifth cervical vertebra (C5) followed by administration of 17β-estradiol via a slow release pellet (0.5 or 5.0 mg/pellet) beginning at 30 minutes post-SCI. Behavioral evaluation of skilled and unskilled forelimb function and locomotor function were conducted for 7 weeks after SCI. Upon conclusion of the behavioral assessments, spinal cords were collected and histochemistry and stereology were conducted to evaluate the effect of treatment on the lesion characteristics. We found that post-SCI administration of 17β-estradiol decreased neuronal loss in the ventral horn, decreased reactive astrogliosis, decreased the immune response, and increased white mater sparing at the lesion epicenter. Additionally, post-SCI administration of 17β-estradiol improved skilled forelimb function and locomotor function. Taken together, these data suggest that post-SCI administration of 17β-estradiol protected both the gray and white matter in cervical SCI. Moreover, this treatment improved function on skilled motor tasks that involve both gray and white matter components, suggesting that this is likely a highly clinically relevant protective strategy.
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Affiliation(s)
- Akkradate Siriphorn
- Center for Glial Biology in Medicine and Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Alabama 35249, USA
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36
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Chan WM, Mohammed Y, Lee I, Pearse DD. Effect of gender on recovery after spinal cord injury. Transl Stroke Res 2013; 4:447-61. [PMID: 24323341 DOI: 10.1007/s12975-012-0249-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 12/26/2012] [Indexed: 11/24/2022]
Abstract
Spinal cord injury (SCI) is a debilitating condition that affects thousands of new individuals each year, the majority of which are males. Males with SCI tend to be injured at an earlier age, mostly during sports or motor vehicle accidents, whereas females tend be injured later in life, particularly in the age group 65 and older. In both experimental and clinical studies, the question as to whether gender affects outcome has been addressed in a variety of patient groups and animal models. Results from experimental paradigms have suggested that a gender bias in outcome exists that favors females and appears to involve the advantageous or disadvantageous effects of the gonadal sex hormones estrogen and progesterone or testosterone, respectively. However, other studies have shown an absence of gender differences in outcome in specific SCI models and work has also questioned the involvement of female sex hormones in the observed outcome improvements in females. Similar controversy exists clinically, in studies that have examined gender disparities in outcome after SCI. The current review examines the experimental and clinical evidence for a gender bias in outcome following SCI and discusses issues that have made it difficult to conclusively answer this question.
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Affiliation(s)
- Wai-Man Chan
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
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Byers JS, Huguenard AL, Kuruppu D, Liu NK, Xu XM, Sengelaub DR. Neuroprotective effects of testosterone on motoneuron and muscle morphology following spinal cord injury. J Comp Neurol 2012; 520:2683-96. [PMID: 22314886 PMCID: PMC3960947 DOI: 10.1002/cne.23066] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Treatment with testosterone is neuroprotective/neurotherapeutic after a variety of motoneuron injuries. Here we assessed whether testosterone might have similar beneficial effects after spinal cord injury (SCI). Young adult female rats received either sham or T9 spinal cord contusion injuries and were implanted with blank or testosterone-filled Silastic capsules. Four weeks later, motoneurons innervating the vastus lateralis muscle of the quadriceps were labeled with cholera toxin-conjugated horseradish peroxidase, and dendritic arbors were reconstructed in three dimensions. Soma volume, motoneuron number, lesion volume, and tissue sparing were also assessed, as were muscle weight, fiber cross-sectional area, and motor endplate size and density. Contusion injury resulted in large lesions, with no significant differences in lesion volume, percent total volume of lesion, or spared white or gray matter between SCI groups. SCI with or without testosterone treatment also had no effect on the number or soma volume of quadriceps motoneurons. However, SCI resulted in a decrease in dendritic length of quadriceps motoneurons in untreated animals, and this decrease was completely prevented by treatment with testosterone. Similarly, the vastus lateralis muscle weights and fiber cross-sectional areas of untreated SCI animals were smaller than those of sham-surgery controls, and these reductions were both prevented by testosterone treatment. No effects on motor endplate area or density were observed across treatment groups. These findings suggest that regressive changes in motoneuron and muscle morphology seen after SCI can be prevented by testosterone treatment, further supporting a role for testosterone as a neurotherapeutic agent in the injured nervous system.
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Affiliation(s)
- James S. Byers
- Program in Neuroscience and Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405
| | - Anna L. Huguenard
- Program in Neuroscience and Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405
| | - Dulanji Kuruppu
- Program in Neuroscience and Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405
| | - Nai-Kui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, and Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, and Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Dale R. Sengelaub
- Program in Neuroscience and Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405
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Siegel C, Turtzo C, McCullough LD. Sex differences in cerebral ischemia: possible molecular mechanisms. J Neurosci Res 2010; 88:2765-74. [PMID: 20698025 DOI: 10.1002/jnr.22406] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sex is emerging as an important factor in the etiology and expression of many different pathological conditions, including stroke. Initially, the levels of sex hormones were thought to be the major contributor to these sex differences, especially after puberty, when gonadal steroid levels sharply diverge between the sexes. More recently, it is recognized that sex differences also result from the organizational effects of sex hormone exposure early in development, even in the absence of hormone exposure later in life, as well as effects mediated by the sex chromosomes themselves. Epigenetic modifications of developmental genes important in sexual differentiation and the response to sex steroid hormones are also emerging as another important contributor to sex differences in disease expression. This review describes recent research on the relationship between hormones, organizational-activational effects of gonadal steroids, and epigenetic modifications in brain pathology, focusing specifically on cerebral ischemia.
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Affiliation(s)
- Chad Siegel
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut 06030, USA
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Kachadroka S, Hall AM, Niedzielko TL, Chongthammakun S, Floyd CL. Effect of endogenous androgens on 17beta-estradiol-mediated protection after spinal cord injury in male rats. J Neurotrauma 2010; 27:611-26. [PMID: 20001688 DOI: 10.1089/neu.2009.1069] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Several groups have recently shown that 17beta-estradiol is protective in spinal cord injury (SCI). Testosterone can be aromatized to 17beta-estradiol and may increase estrogen-mediated protection. Alternatively, testosterone has been shown to increase excitotoxicity in models of central nervous system (CNS) injury. These experiments test the hypothesis that endogenous testosterone in male rats alters 17beta-estradiol-mediated protection by evaluating a delayed administration over a clinically relevant dose range and manipulating testicular-derived testosterone. Adult male Sprague Dawley rats were either gonadectomized or left gonad-intact prior to SCI. SCI was produced by a midthoracic crush injury. At 30 min post SCI, animals received a subcutaneous pellet of 0.0, 0.05, 0.5, or 5.0 mg of 17beta-estradiol, released over 21 days. Hindlimb locomotion was analyzed weekly in the open field. Spinal cords were collected and analyzed for cell death, expression of Bcl-family proteins, and white-matter sparing. Post-SCI administration of the 0.5- or 5.0-mg pellet improved hindlimb locomotion, reduced urinary bladder size, increased neuronal survival, reduced apoptosis, improved the Bax/Bcl-xL protein ratio, and increased white-matter sparing. In the absence of endogenous testicular-derived androgens, SCI induced greater apoptosis, yet 17beta-estradiol administration reduced apoptosis to the same extent in gonadectomized and gonad-intact male rats. These data suggest that delayed post-SCI administration of a clinically relevant dose of 17beta-estradiol is protective in male rats, and endogenous androgens do not alter estrogen-mediated protection. These data suggest that 17beta-estradiol is an effective therapeutic intervention for reducing secondary damage after SCI in males, which could be readily translated to clinical trials.
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Affiliation(s)
- Supatra Kachadroka
- Department of Physical Medicine and Rehabilitation, Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, Alhabama 35249, USA
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40
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Immune senescence and brain aging: can rejuvenation of immunity reverse memory loss? Trends Neurosci 2009; 32:367-75. [PMID: 19520437 DOI: 10.1016/j.tins.2009.03.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2008] [Revised: 02/19/2009] [Accepted: 03/02/2009] [Indexed: 12/11/2022]
Abstract
The factors that determine brain aging remain a mystery. Do brain aging and memory loss reflect processes occurring only within the brain? Here, we present a novel view, linking aging of adaptive immunity to brain senescence and specifically to spatial memory deterioration. Inborn immune deficiency, in addition to sudden imposition of immune malfunction in young animals, results in cognitive impairment. As a corollary, immune restoration at adulthood or in the elderly results in a reversal of memory loss. These results, together with the known deterioration of adaptive immunity in the elderly, suggest that memory loss does not solely reflect chronological age; rather, it is an outcome of the gap between an increasing demand for maintenance (age-related risk-factor accumulation) and the reduced ability of the immune system to meet these needs.
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41
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42
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Graber JJ, Dhib-Jalbut S. Protective autoimmunity in the nervous system. Pharmacol Ther 2008; 121:147-59. [PMID: 19000712 DOI: 10.1016/j.pharmthera.2008.10.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Accepted: 10/02/2008] [Indexed: 12/31/2022]
Abstract
The immune system can play both detrimental and beneficial roles in the nervous system. Multiple arms of the immune system, including T cells, B cells, NK cells, mast cells, macrophages, dendritic cells, microglia, antibodies, complement and cytokines participate in limiting damage to the nervous system during toxic, ischemic, hemorrhagic, infective, degenerative, metabolic and immune-mediated insults and also assist in the process of repair after injury has occurred. Immune cells have been shown to produce neurotrophic growth factors and interact with neurons and glial cells to preserve them from injury and stimulate growth and repair. The immune system also appears to participate in proliferation of neural progenitor stem cells and their migration to sites of injury. Neural stem cells can also modify the immune response in the central and peripheral nervous system to enhance neuroprotective effects. Evidence for protective and reparative functions of the immune system has been found in diverse neurologic diseases including traumatic injury, ischemic and hemorrhagic stroke, multiple sclerosis, infection, and neurodegenerative diseases (Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis). Existing therapies including glatiramer acetate, interferon-beta and immunoglobulin have been shown to augment the protective and regenerative aspects of the immune system in humans, and other experimental interventions such as vaccination, minocycline, antibodies and neural stem cells, have shown promise in animal models of disease. The beneficent aspects of the immune response in the nervous system are beginning to be appreciated and their potential as pharmacologic targets in neurologic disease is being explored.
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Affiliation(s)
- Jerome J Graber
- New York University School of Medicine, Department of Neurology, New York, NY, USA
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43
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Liu M, Zhao J, Liang H, Bian X. Vaccination with dendritic cells pulsed with homogenate protein of spinal cord promotes functional recovery from spinal cord injury in mice. Spinal Cord 2008; 47:360-6. [DOI: 10.1038/sc.2008.112] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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Doperalski NJ, Sandhu MS, Bavis RW, Reier PJ, Fuller DD. Ventilation and phrenic output following high cervical spinal hemisection in male vs. female rats. Respir Physiol Neurobiol 2008; 162:160-7. [PMID: 18586119 DOI: 10.1016/j.resp.2008.06.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Revised: 06/05/2008] [Accepted: 06/05/2008] [Indexed: 02/02/2023]
Abstract
Female sex hormones influence the neural control of breathing and may impact neurologic recovery from spinal cord injury. We hypothesized that respiratory recovery after C2 spinal hemisection (C2HS) differs between males and females and is blunted by prior ovariectomy (OVX) in females. Inspiratory tidal volume (VT), frequency (fR), and ventilation (VE) were quantified during quiet breathing (baseline) and 7% CO2 challenge before and after C2HS in unanesthetized adult rats via plethysmography. Baseline breathing was similarly altered in all rats (reduced VT, elevated fR) but during hypercapnia females had relatively higher VT (i.e. compared to pre-injury) than male or OVX rats (p<0.05). Phrenic neurograms recorded in anesthetized rats indicated that normalized burst amplitude recorded ipsilateral to C2HS (i.e. the crossed phrenic phenomenon) is greater in females during respiratory challenge (p<0.05 vs. male and OVX). We conclude that sex differences in recovery of VT and phrenic output are present at 2 weeks post-C2HS. These differences are consistent with the hypothesis that ovarian sex hormones influence respiratory recovery after cervical spinal cord injury.
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Affiliation(s)
- N J Doperalski
- University of Florida, College of Public Health and Health Professions, Department of Physical Therapy, PO Box 100154, 100 Newell Drive, Gainesville, FL 32610, USA
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Abstract
This symposium aims at summarizing some of the scientific bases for current or planned clinical trials in patients with spinal cord injury (SCI). It stems from the interactions of four researchers involved in basic and clinical research who presented their work at a dedicated Symposium of the Society for Neuroscience in San Diego. After SCI, primary and secondary damage occurs and several endogenous processes are triggered that may foster or hinder axonal reconnection from supralesional structures. Studies in animals show that some of these processes can be enhanced or decreased by exogenous interventions using drugs to diminish repulsive barriers (anti-Nogo, anti-Rho) that prevent regeneration and/or sprouting of axons. Cell grafts are also envisaged to enhance beneficial immunological mechanisms (autologous macrophages, vaccines) or remyelinate axons (oligodendrocytes derived from stem cells). Some of these treatments could be planned concurrently with neurosurgical approaches that are themselves beneficial to decrease secondary damage (e.g., decompression/reconstructive spinal surgery). Finally, rehabilitative approaches based on the presence of functional networks (i.e., central pattern generator) below the lesion combined with the above neurobiological approaches may produce significant functional recovery of some sensorimotor functions, such as locomotion, by ensuring an optimal function of endogenous spinal networks and establishing new dynamic interactions with supralesional structures. More work is needed on all fronts, but already the results offer great hope for functional recovery after SCI based on sound basic and clinical neuroscience research.
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46
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The role of tissue adaptation and graft size in immune tolerance. Transpl Immunol 2007; 18:122-5. [DOI: 10.1016/j.trim.2007.05.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Accepted: 05/21/2007] [Indexed: 11/23/2022]
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Swartz KR, Fee DB, Joy KM, Roberts KN, Sun S, Scheff NN, Wilson ME, Scheff SW. Gender differences in spinal cord injury are not estrogen-dependent. J Neurotrauma 2007; 24:473-80. [PMID: 17402853 DOI: 10.1089/neu.2006.0167] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recent attention has been given to gender differences in neurotrauma, and the anecdotal suggestion is that females have better outcomes than males, suggesting that circulating levels of estrogen (E(2)) may be neuroprotective. In order to address this issue, both young adult male and ovariectomized female rats were subjected to a T10 spinal cord injury (SCI), and E2 levels were maintained at chronic, constant circulating levels. Animals were clinically evaluated for locomotor changes using the Basso-Beattie-Bresnahan (BBB) scoring system. Morphologic differences were evaluated with unbiased stereology. Data analysis failed to reveal any significant benefit for the E2 therapy in either males or females. We did find a non-estrogen-dependent difference between male and female rats in length of injury, and percent of spared tissue, with female outcomes more favorable. These results suggest that E(2) does not provide a viable therapy following SCI.
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Affiliation(s)
- Karin R Swartz
- Division of Neurosurgery, Department of Surgery, University of Kentucky Medical Center, Lexington, Kentucky 40536, USA.
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48
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Schori H, Shechter R, Shachar I, Schwartz M. Genetic manipulation of CD74 in mouse strains of different backgrounds can result in opposite responses to central nervous system injury. THE JOURNAL OF IMMUNOLOGY 2007; 178:163-71. [PMID: 17182551 DOI: 10.4049/jimmunol.178.1.163] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The ability to recover from CNS injuries is strain dependent. Transgenic mice that weakly express the p41 CD74 isoform (an integral membrane protein functioning as a MHC class II chaperone) on an I-A(b) genetic background have normal CD4(+) T cell populations and normal surface expression of MHC class II, but their B cell development is arrested while the cells are still immature. After a CNS injury, these mice recover better than their matched wild-type controls. We generated p41-transgenic mice on an I-A(d) background (p41-I-A(d) mice), and found that their recovery from CNS injuries was worse than that of controls. A correlative inverse effect was seen with respect to the kinetics of T cell and B cell recruitment to the injured CNS and the expression of insulin-like growth factor at the lesion site. These results, besides verifying previous findings that B cells function in the damaged CNS, demonstrate that the outcome of a particular genetic manipulation may be strain dependent.
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Affiliation(s)
- Hadas Schori
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel
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49
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Berrocal YA, Pearse DD, Andrade CM, Hechtman JF, Puentes R, Eaton MJ. Increased spinal c-Fos expression with noxious and non-noxious peripheral stimulation after severe spinal contusion. Neurosci Lett 2006; 413:58-62. [PMID: 17161529 DOI: 10.1016/j.neulet.2006.11.030] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Revised: 11/13/2006] [Accepted: 11/13/2006] [Indexed: 11/20/2022]
Abstract
The effects of severe contusive spinal cord injury (SCI), at thoracic level 8 (T8), on lumbar c-Fos expression in the spinal cord was investigated. As hypothesized, chronic SCI has a significant effect on expression of c-Fos in the dorsal spinal sensory areas with noxious and innocuous peripheral stimulation of the sciatic nerve. This alteration to stimulation effects was measured using counts of c-Fos immunoreactive cells in the dorsal horn of the L5 lumbar spinal cord in injured animals at 90 days post-injury and in uninjured controls. The number of c-Fos immunoreactive cells increased in SCI rats only after noxious peripheral stimulation (electrical and chemical) suggesting a general increase in excitability in spinal pathways (central sensitization) associated with chronic SCI. These altered responses may represent a functional anatomical reorganization of spinal cord circuitry leading to increased dorsal horn c-Fos expression as a response to severe chronic contusive damage to the spinal cord sensory pathways.
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Affiliation(s)
- Y A Berrocal
- The Miami Project to Cure Paralysis, Miami, FL 33136, United States
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50
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Kang SK, So HH, Moon YS, Kim CH. Proteomic analysis of injured spinal cord tissue proteins using 2-DE and MALDI-TOF MS. Proteomics 2006; 6:2797-812. [PMID: 16586436 DOI: 10.1002/pmic.200500621] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Spinal cord injury (SCI) induces a progressive pathophysiology affecting cell survival and neurological integrity via complex and evolving molecular cascades whose interrelationships are not fully understood. Acute injury to the spinal cord undergoes sequential pathological change including hemorrhage, edema, axonal and neuronal necrosis, and demyelination. In the present study, we aimed to establish the proteomic profiles and characterization of the total protein expressed in traumatic injured spinal cord tissue by using 2-DE and matrix assisted laser desorption/ionization-TOF MS (MALDI-TOF MS). We performed proteomic analysis using 2-DE and MS to describe total proteins and differential proteins expression between normal and traumatic injured spinal cord tissues. The study discovered 947 total proteins and analyzed 219 and 270 proteins from normal and injured tissue, respectively. After 24 h of traumatic damage induction, the injured spinal cord tissue up-regulated over 39 proteins including neurofilament light chain, annexin 5, heat shock protein, tubulin beta, peripherin, glial fibrillary acidic protein delta, peroxiredoxin 2, and apolipoprotein A. Twenty-one proteins showed reduction. The majority of the modulated proteins belonged to the 13 functional categories. Proteins that were identified with neural functional category in injured tissue were considered most likely to be involved in wound healing response coupled with neurogenesis and gliogenesis.
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Affiliation(s)
- Soo Kyung Kang
- Department of Physiology, College of Medicine, Pusan National University, Busan, South Korea.
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