1
|
Wu Z, Feng K, Huang J, Ye X, Yang R, Huang Q, Jiang Q. Brain region changes following a spinal cord injury. Neurochem Int 2024; 174:105696. [PMID: 38354751 DOI: 10.1016/j.neuint.2024.105696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 01/16/2024] [Accepted: 02/10/2024] [Indexed: 02/16/2024]
Abstract
Brain-related complications are common in clinical practice after spinal cord injury (SCI); however, the molecular mechanisms of these complications are still unclear. Here, we reviewed the changes in the brain regions caused by SCI from three perspectives: imaging, molecular analysis, and electrophysiology. Imaging studies revealed abnormal functional connectivity, gray matter volume atrophy, and metabolic abnormalities in brain regions after SCI, leading to changes in the structure and function of brain regions. At the molecular level, chemokines, inflammatory factors, and damage-associated molecular patterns produced in the injured area were retrogradely transmitted through the corticospinal tract, cerebrospinal fluid, or blood circulation to the specific brain area to cause pathologic changes. Electrophysiologic recordings also suggested abnormal changes in brain electrical activity after SCI. Transcranial magnetic stimulation, transcranial direct current stimulation, and deep brain stimulation alleviated pain and improved motor function in patients with SCI; therefore, transcranial therapy may be a new strategy for the treatment of patients with SCI.
Collapse
Affiliation(s)
- Zhiwu Wu
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China
| | - Kaiming Feng
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China
| | - Jinqing Huang
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China
| | - Xinyun Ye
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China
| | - Ruijin Yang
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China
| | - Qianliang Huang
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China.
| | - Qiuhua Jiang
- Department of Neurosurgery, Ganzhou People's Hospital (Ganzhou Hospital-Nanfang Hospital, Southern Medical University), 16th Mei-guan Avenue, Ganzhou, 341000, China.
| |
Collapse
|
2
|
The role of PI3K/Akt signalling pathway in spinal cord injury. Biomed Pharmacother 2022; 156:113881. [DOI: 10.1016/j.biopha.2022.113881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 10/13/2022] [Accepted: 10/13/2022] [Indexed: 11/18/2022] Open
|
3
|
He X, Li Y, Deng B, Lin A, Zhang G, Ma M, Wang Y, Yang Y, Kang X. The PI3K/AKT signalling pathway in inflammation, cell death and glial scar formation after traumatic spinal cord injury: Mechanisms and therapeutic opportunities. Cell Prolif 2022; 55:e13275. [PMID: 35754255 PMCID: PMC9436900 DOI: 10.1111/cpr.13275] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/17/2022] [Accepted: 05/24/2022] [Indexed: 02/06/2023] Open
Abstract
Objects Traumatic spinal cord injury (TSCI) causes neurological dysfunction below the injured segment of the spinal cord, which significantly impacts the quality of life in affected patients. The phosphoinositide 3kinase/serine‐threonine kinase (PI3K/AKT) signaling pathway offers a potential therapeutic target for the inhibition of secondary TSCI. This review summarizes updates concerning the role of the PI3K/AKT pathway in TSCI. Materials and Methods By searching articles related to the TSCI field and the PI3K/AKT signaling pathway, we summarized the mechanisms of secondary TSCI and the PI3K/AKT signaling pathway; we also discuss current and potential future treatment methods for TSCI based on the PI3K/AKT signaling pathway. Results Early apoptosis and autophagy after TSCI protect the body against injury; a prolonged inflammatory response leads to the accumulation of pro‐inflammatory factors and excessive apoptosis, as well as excessive autophagy in the surrounding normal nerve cells, thus aggravating TSCI in the subacute stage of secondary injury. Initial glial scar formation in the subacute phase is a protective mechanism for TSCI, which limits the spread of damage and inflammation. However, mature scar tissue in the chronic phase hinders axon regeneration and prevents the recovery of nerve function. Activation of PI3K/AKT signaling pathway can inhibit the inflammatory response and apoptosis in the subacute phase after secondary TSCI; inhibiting this pathway in the chronic phase can reduce the formation of glial scar. Conclusion The PI3K/AKT signaling pathway has an important role in the recovery of spinal cord function after secondary injury. Inducing the activation of PI3K/AKT signaling pathway in the subacute phase of secondary injury and inhibiting this pathway in the chronic phase may be one of the potential strategies for the treatment of TSCI.
Collapse
Affiliation(s)
- Xuegang He
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China.,The International Cooperation Base of Gansu Province for the Pain Research in Spinal Disorders, Lanzhou, China
| | - Ying Li
- Medical School of Yan'an University, Yan'an University, Yan'an, China
| | - Bo Deng
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Aixin Lin
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China.,The International Cooperation Base of Gansu Province for the Pain Research in Spinal Disorders, Lanzhou, China
| | - Guangzhi Zhang
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China.,The International Cooperation Base of Gansu Province for the Pain Research in Spinal Disorders, Lanzhou, China
| | - Miao Ma
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Yonggang Wang
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China.,The International Cooperation Base of Gansu Province for the Pain Research in Spinal Disorders, Lanzhou, China
| | - Yong Yang
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The International Cooperation Base of Gansu Province for the Pain Research in Spinal Disorders, Lanzhou, China
| | - Xuewen Kang
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, China.,The Second Clinical Medical College, Lanzhou University, Lanzhou, China.,The International Cooperation Base of Gansu Province for the Pain Research in Spinal Disorders, Lanzhou, China
| |
Collapse
|
4
|
Warren PM, Kissane RWP, Egginton S, Kwok JCF, Askew GN. Oxygen transport kinetics underpin rapid and robust diaphragm recovery following chronic spinal cord injury. J Physiol 2020; 599:1199-1224. [PMID: 33146892 PMCID: PMC7894160 DOI: 10.1113/jp280684] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/29/2020] [Indexed: 12/16/2022] Open
Abstract
Key points Spinal treatment can restore diaphragm function in all animals 1 month following C2 hemisection induced paralysis. Greater recovery occurs the longer after injury the treatment is applied. Through advanced assessment of muscle mechanics, innovative histology and oxygen tension modelling, we have comprehensively characterized in vivo diaphragm function and phenotype. Muscle work loops reveal a significant deficit in diaphragm functional properties following chronic injury and paralysis, which are normalized following restored muscle activity caused by plasticity‐induced spinal reconnection. Injury causes global and local alterations in diaphragm muscle vascular supply, limiting oxygen diffusion and disturbing function. Restoration of muscle activity reverses these alterations, restoring oxygen supply to the tissue and enabling recovery of muscle functional properties. There remain metabolic deficits following restoration of diaphragm activity, probably explaining only partial functional recovery. We hypothesize that these deficits need to be resolved to restore complete respiratory motor function.
Abstract Months after spinal cord injury (SCI), respiratory deficits remain the primary cause of morbidity and mortality for patients. It is possible to induce partial respiratory motor functional recovery in chronic SCI following 2 weeks of spinal neuroplasticity. However, the peripheral mechanisms underpinning this recovery are largely unknown, limiting development of new clinical treatments with potential for complete functional restoration. Utilizing a rat hemisection model, diaphragm function and paralysis was assessed and recovered at chronic time points following trauma through chondroitinase ABC induced neuroplasticity. We simulated the diaphragm's in vivo cyclical length change and activity patterns using the work loop technique at the same time as assessing global and local measures of the muscles histology to quantify changes in muscle phenotype, microvascular composition, and oxidative capacity following injury and recovery. These data were fed into a physiologically informed model of tissue oxygen transport. We demonstrate that hemidiaphragm paralysis causes muscle fibre hypertrophy, maintaining global oxygen supply, although it alters isolated muscle kinetics, limiting respiratory function. Treatment induced recovery of respiratory activity normalized these effects, increasing oxygen supply, restoring optimal diaphragm functional properties. However, metabolic demands of the diaphragm were significantly reduced following both injury and recovery, potentially limiting restoration of normal muscle performance. The mechanism of rapid respiratory muscle recovery following spinal trauma occurs through oxygen transport, metabolic demand and functional dynamics of striated muscle. Overall, these data support a systems‐wide approach to the treatment of SCI, and identify new targets to mediate complete respiratory recovery. Spinal treatment can restore diaphragm function in all animals 1 month following C2 hemisection induced paralysis. Greater recovery occurs the longer after injury the treatment is applied. Through advanced assessment of muscle mechanics, innovative histology and oxygen tension modelling, we have comprehensively characterized in vivo diaphragm function and phenotype. Muscle work loops reveal a significant deficit in diaphragm functional properties following chronic injury and paralysis, which are normalized following restored muscle activity caused by plasticity‐induced spinal reconnection. Injury causes global and local alterations in diaphragm muscle vascular supply, limiting oxygen diffusion and disturbing function. Restoration of muscle activity reverses these alterations, restoring oxygen supply to the tissue and enabling recovery of muscle functional properties. There remain metabolic deficits following restoration of diaphragm activity, probably explaining only partial functional recovery. We hypothesize that these deficits need to be resolved to restore complete respiratory motor function.
Collapse
Affiliation(s)
- Philippa M Warren
- The Wolfson Centre for Age-Related Diseases, Guy's Campus, King's College London, London, UK.,School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Roger W P Kissane
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK.,Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Stuart Egginton
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Jessica C F Kwok
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK.,Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czech Republic
| | - Graham N Askew
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| |
Collapse
|
5
|
Zhang H, Gong M, Luo X. Methoxytetrahydro-2H-pyran-2-yl)methyl benzoate inhibits spinal cord injury in the rat model via PPAR-γ/PI3K/p-Akt activation. ENVIRONMENTAL TOXICOLOGY 2020; 35:714-721. [PMID: 32149473 DOI: 10.1002/tox.22902] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 12/28/2019] [Accepted: 01/17/2020] [Indexed: 06/10/2023]
Abstract
Spinal cord injury (SCI) is the most commonly seen trauma leading to disability in people worldwide. The purpose of current study was to determine the protective effect of methoxytetrahydro-2H-pyran-2-yl)methyl benzoate (HMPB) on SCI in rat model. TUNEL staining was used to examine apoptotic changes in spinal cord of SCI rats. The ELISA kits were employed to assess inflammatory processes and oxidative factors in the spinal cord tissues. Behavioral changes in SCI rats were assessed using Basso, Beattie, and Bresnahan (BBB) scoring system. Western blotting was used for assessment of proteins. The HMPB treatment of SCI rats reduced apoptotic cell number based on the concentration of dose administered. Treatment of SCI rats with HMPB enhanced BBB score and decreased accumulation of water content in SCI rats significantly. On treatment with HMPB the TNF-α and interleukin-6/1β/18 levels were suppressed in SCI rats. Treatment with HMPB induced excessive release of SOD, CAT, and GSH molecules and decreased overproduction of MDA. The SCI induced upregulation of caspase-3/9 activity was completely alleviated by HMPB at 2 mg/kg dose. The HMPB treatment of SCI rats promoted peroxisome proliferator-activated receptor γ (PPAR-γ) expression, reduced cyclooxygenase (COX)-2 production and increased expression of p-Akt and phosphoinositide 3-kinase (p-PI3K). The study demonstrated that HMPB suppressed apoptosis, raised BBB score and inhibited inflammation in SCI rats. Moreover, activation of PI3K/Akt in the spinal cord tissues of SCI rats was promoted by HMPB. Therefore, HMPB has protective effect on SCI in the rat model.
Collapse
Affiliation(s)
- Hao Zhang
- Department of Spinal surgery, The People's Hospital of Longhua, Shenzhen, China
| | - Ming Gong
- Department of Spinal surgery, The People's Hospital of Longhua, Shenzhen, China
| | - Xinle Luo
- Department of Spinal surgery, The People's Hospital of Longhua, Shenzhen, China
| |
Collapse
|
6
|
Warren PM, Alilain WJ. Plasticity Induced Recovery of Breathing Occurs at Chronic Stages after Cervical Contusion. J Neurotrauma 2019; 36:1985-1999. [PMID: 30565484 DOI: 10.1089/neu.2018.6186] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Severe midcervical contusion injury causes profound deficits throughout the respiratory motor system that last from acute to chronic time points post-injury. We use chondroitinase ABC (ChABC) to digest chondroitin sulphate proteoglycans within the extracellular matrix (ECM) surrounding the respiratory system at both acute and chronic time points post-injury to explore whether augmentation of plasticity can recover normal motor function. We demonstrate that, regardless of time post-injury or treatment application, the lesion cavity remains consistent, showing little regeneration or neuroprotection within our model. Through electromyography (EMG) recordings of multiple inspiratory muscles, however, we show that application of the enzyme at chronic time points post-injury initiates the recovery of normal breathing in previously paralyzed respiratory muscles. This reduced the need for compensatory activity throughout the motor system. Application of ChABC at acute time points recovered only modest amounts of respiratory function. To further understand this effect, we assessed the anatomical mechanism of this recovery. Increased EMG activity in previously paralyzed muscles was brought about by activation of spared bulbospinal pathways through the site of injury and/or sprouting of spared serotonergic fibers from the contralateral side of the cord. Accordingly, we demonstrate that alterations to the ECM and augmentation of plasticity at chronic time points post-cervical contusion can cause functional recovery of the respiratory motor system and reveal mechanistic evidence of the pathways that govern this effect.
Collapse
Affiliation(s)
- Philippa Mary Warren
- 1 Department of Neurosciences, MetroHealth Medical Centre, Case Western Reserve University, Cleveland, Ohio.,2 King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, Guy's Campus, London Bridge, London, United Kingdom
| | - Warren Joseph Alilain
- 1 Department of Neurosciences, MetroHealth Medical Centre, Case Western Reserve University, Cleveland, Ohio.,3 Department of Neuroscience, Spinal Cord and Brain Injury Research Centre, University of Kentucky, Lexington, Kentucky
| |
Collapse
|
7
|
Chen Y, Wang B, Zhao H. Thymoquinone reduces spinal cord injury by inhibiting inflammatory response, oxidative stress and apoptosis via PPAR-γ and PI3K/Akt pathways. Exp Ther Med 2018; 15:4987-4994. [PMID: 29904397 DOI: 10.3892/etm.2018.6072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 09/01/2017] [Indexed: 01/03/2023] Open
Abstract
The present study used a mild contusion injury in rat spinal cord to determine that thymoquinone reduces inflammatory response, oxidative stress and apoptosis in a spinal cord injury (SCI) rat model and to demonstrate its possible molecular mechanisms. The rats in the thymoquinone group received 30 mg/kg thymoquinone once daily by intragastric administration from 3 weeks after surgery. Hematoxylin and eosin staining, Basso, Beattie and Bresnahan (BBB) scale and tissue water content detection were used in the present study to analyze the effect of thymoquinone on SCI. The activity of inflammatory response mediators, oxidative stress factors and caspase-3/9 was measured using ELISA kits. Furthermore, western blotting was performed to analyzed the protein expression levels of prostaglandin E2, suppressed cyclooxygenase-2 (COX-2) and activated peroxisome proliferator-activated receptor γ (PPAR-γ), PI3K and Akt. The results from the study demonstrated that thymoquinone increased Basso, Beattie and Bresnahan score and decreased water content in spinal cord tissue. Treatment with thymoquinone decreased inflammatory response [measured by levels of tumor necrosis factor α, interleukin (IL)-1β, IL-6 and IL-18], oxidative stress (measured by levels of superoxide dismutase, catalase, glutathione and malondialdehyde) and cell apoptosis (measured by levels of caspase-3 and caspase-9) in SCI rats. Thymoquinone treatment inhibited prostaglandin E2 activity, suppressed COX-2 protein expression and activated PPAR-γ, PI3K and p-Akt protein expression in SCI rats. These data revealed that thymoquinone reduces inflammatory response, oxidative stress and apoptosis via PPAR-γ and PI3K/Akt pathways in an SCI rat model.
Collapse
Affiliation(s)
- Yinming Chen
- Department of Orthopedics, Zaozhuang Municipal Hospital, Zaozhuang, Shandong 277102, P.R. China
| | - Benlong Wang
- Department of Orthopedics, Zaozhuang Municipal Hospital, Zaozhuang, Shandong 277102, P.R. China
| | - Hai Zhao
- Department of Orthopedics, Zaozhuang Municipal Hospital, Zaozhuang, Shandong 277102, P.R. China
| |
Collapse
|
8
|
Warren PM, Campanaro C, Jacono FJ, Alilain WJ. Mid-cervical spinal cord contusion causes robust deficits in respiratory parameters and pattern variability. Exp Neurol 2018; 306:122-131. [PMID: 29653187 PMCID: PMC6333202 DOI: 10.1016/j.expneurol.2018.04.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/24/2018] [Accepted: 04/06/2018] [Indexed: 02/08/2023]
Abstract
Mid-cervical spinal cord contusion disrupts both the pathways and motoneurons vital to the activity of inspiratory muscles. The present study was designed to determine if a rat contusion model could result in a measurable deficit to both ventilatory and respiratory motor function under “normal” breathing conditions at acute to chronic stages post trauma. Through whole body plethysmography and electromyography we assessed respiratory output from three days to twelve weeks after a cervical level 3 (C3) contusion. Contused animals showed significant deficits in both tidal and minute volumes which were sustained from acute to chronic time points. We also examined the degree to which the contusion injury impacted ventilatory pattern variability through assessment of Mutual Information and Sample Entropy. Mid-cervical contusion significantly and robustly decreased the variability of ventilatory patterns. The enduring deficit to the respiratory motor system caused by contusion was further confirmed through electromyography recordings in multiple respiratory muscles. When isolated via a lesion, these contused pathways were insufficient to maintain respiratory activity at all time points post injury. Collectively these data illustrate that, counter to the prevailing literature, a profound and lasting ventilatory and respiratory motor deficit may be modelled and measured through multiple physiological assessments at all time points after cervical contusion injury.
Collapse
Affiliation(s)
- Philippa M Warren
- Department of Neurosciences, MetroHealth Medical Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Cara Campanaro
- Division of Pulmonary Critical Care and Sleep Medicine and Louis Stokes VA Medical Center, Department of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Frank J Jacono
- Division of Pulmonary Critical Care and Sleep Medicine and Louis Stokes VA Medical Center, Department of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Warren J Alilain
- Department of Neurosciences, MetroHealth Medical Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Spinal Cord and Brain Injury Research Centre, University of Kentucky, Lexington, KY 40536, USA.
| |
Collapse
|
9
|
Lu H, Zhang LH, Yang L, Tang PF. The PI3K/Akt/FOXO3a pathway regulates regeneration following spinal cord injury in adult rats through TNF-α and p27kip1 expression. Int J Mol Med 2018; 41:2832-2838. [PMID: 29436581 DOI: 10.3892/ijmm.2018.3459] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 12/20/2017] [Indexed: 11/06/2022] Open
Abstract
The aim of the present study was to elucidate the expression and role of the phosphatidylinositol 3‑kinase (PI3K)/Akt/forkhead box O3 (FOXO3a) pathway in the regeneration of the spinal cord following spinal cord injury (SCI), and its regulatory effect on tumor necrosis factor (TNF)-α and cyclin-dependent kinase inhibitor 1B (p27kip1) expression. Firstly, in a Sprague-Dawley rat model of SCI, western blot analysis revealed that the protein levels of PI3K, phosphorylated Akt and FOXO3a were markedly inhibited compared with those in the sham control group. In vitro experiments were also conducted, in which primary dissociated cultures of rat dorsal spinal cord cells were induced with lipopolysaccharide (LPS; 4 µg/ml). The downregulation of PI3K using LY294002 markedly suppressed cell viability, reduced the protein levels of FOXO3a and p27kip1, and increased TNF-α protein production in the LPS-induced spinal cord cells. In addition, when the LPS-induced spinal cord cells were infected with FOXO3a adenoviral vectors, the overexpression of FOXO3 markedly promoted cell proliferation, activated p27kip1 protein levels and inhibited TNF-α protein production in the spinal cord cells. These results suggest that the PI3K/Akt/FOXO3a pathway regulates regeneration following SCI in adult rats via its modulatory effects on TNF-α and p27kip1 expression.
Collapse
Affiliation(s)
- Honghui Lu
- Department of Orthopaedics, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing 100853, P.R. China
| | - Li-Hai Zhang
- Department of Orthopaedics, Chinese PLA General Hospital, Beijing 100853, P.R. China
| | - Lin Yang
- Department of Orthopaedics, The Third Hospital of Beijing Municipal Corps, Chinese People's Armed Police Forces, Beijing 100141, P.R. China
| | - Pei-Fu Tang
- Department of Orthopaedics, Chinese PLA General Hospital, Beijing 100853, P.R. China
| |
Collapse
|
10
|
Darlot F, Vinit S, Matarazzo V, Kastner A. Sustained cell body reactivity and loss of NeuN in a subset of axotomized bulbospinal neurons after a chronic high cervical spinal cord injury. Eur J Neurosci 2017; 46:2729-2745. [PMID: 28977718 DOI: 10.1111/ejn.13737] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/28/2017] [Accepted: 09/28/2017] [Indexed: 12/15/2022]
Abstract
Following central nervous system lesion, the ability of injured axons to regrowth may depend on the level and duration of the injured cell body response (CBR). Therefore, to investigate whether axotomized brainstem neurons maintain a durable growth-competent state after spinal cord injury, we studied the effect of a chronic C2 hemisection in rats on the expression of various CBR markers involved in axon regeneration, such as c-Jun, ATF-3, HSP27, NO synthase (NOS), and also of the neural mature phenotype marker NeuN, in the bulbospinal respiratory neurons as compared to the gigantocellularis nucleus. Both at 7 and 30 days post-lesion (DPL), c-Jun and HSP27 were present in, respectively, ~60 and ~20% of the axotomized respiratory neurons, whereas the apoptotic factor caspase 3 was not detected in these cells. NOS appeared belatedly, and it was detected in ~20% of the axotomized respiratory neurons at 30DPL. At 30DPL, these different CBR markers were strongly colocalized in a sub-population of axotomized respiratory neurons and also in a sub-population of injured neurons within the gigantocellularis nucleus. Such CBR was also accompanied by a sustained alteration of the neural mature phenotype, as indicated by a loss of NeuN immunoreactivity selectively in HSP27+ bulbospinal neurons at 7DPL and 30DPL. Altogether, this study shows that a subset of axotomized medullary respiratory neurons remains in a growth-competent state after a chronic injury, suggesting that they may play a preferential role in long-lasting respiratory neuroplasticity processes.
Collapse
Affiliation(s)
- Fannie Darlot
- Laboratoire de Physiologie et Physiopathologie du Système Nerveux Somatomoteur et Neurovégétatif (PPSN), Aix-Marseille Université, Ave Escadrille Normandie Niemen, 13013, Marseille, France
| | - Stéphane Vinit
- INSERM U1179, Université de Versailles Saint-Quentin-en-Yvelines, Montigny-le-Bretonneux, France
| | | | - Anne Kastner
- Laboratoire de Physiologie et Physiopathologie du Système Nerveux Somatomoteur et Neurovégétatif (PPSN), Aix-Marseille Université, Ave Escadrille Normandie Niemen, 13013, Marseille, France
| |
Collapse
|
11
|
Bezdudnaya T, Marchenko V, Zholudeva LV, Spruance VM, Lane MA. Supraspinal respiratory plasticity following acute cervical spinal cord injury. Exp Neurol 2017; 293:181-189. [PMID: 28433644 PMCID: PMC5510885 DOI: 10.1016/j.expneurol.2017.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 04/06/2017] [Accepted: 04/10/2017] [Indexed: 12/20/2022]
Abstract
Impaired breathing is a devastating result of high cervical spinal cord injuries (SCI) due to partial or full denervation of phrenic motoneurons, which innervate the diaphragm - a primary muscle of respiration. Consequently, people with cervical level injuries often become dependent on assisted ventilation and are susceptible to secondary complications. However, there is mounting evidence for limited spontaneous recovery of respiratory function following injury, demonstrating the neuroplastic potential of respiratory networks. Although many studies have shown such plasticity at the level of the spinal cord, much less is known about the changes occurring at supraspinal levels post-SCI. The goal of this study was to determine functional reorganization of respiratory neurons in the medulla acutely (>4h) following high cervical SCI. Experiments were conducted in decerebrate, unanesthetized, vagus intact and artificially ventilated rats. In this preparation, spontaneous recovery of ipsilateral phrenic nerve activity was observed within 4 to 6h following an incomplete, C2 hemisection (C2Hx). Electrophysiological mapping of the ventrolateral medulla showed a reorganization of inspiratory and expiratory sites ipsilateral to injury. These changes included i) decreased respiratory activity within the caudal ventral respiratory group (cVRG; location of bulbospinal expiratory neurons); ii) increased proportion of expiratory phase activity within the rostral ventral respiratory group (rVRG; location of inspiratory bulbo-spinal neurons); iii) increased respiratory activity within ventral reticular nuclei, including lateral reticular (LRN) and paragigantocellular (LPGi) nuclei. We conclude that disruption of descending and ascending connections between the medulla and spinal cord leads to immediate functional reorganization within the supraspinal respiratory network, including neurons within the ventral respiratory column and adjacent reticular nuclei.
Collapse
Affiliation(s)
- Tatiana Bezdudnaya
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, 2900 W Queen Lane, Philadelphia, PA 19129, USA
| | - Vitaliy Marchenko
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, 2900 W Queen Lane, Philadelphia, PA 19129, USA
| | - Lyandysha V Zholudeva
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, 2900 W Queen Lane, Philadelphia, PA 19129, USA
| | - Victoria M Spruance
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, 2900 W Queen Lane, Philadelphia, PA 19129, USA
| | - Michael A Lane
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, 2900 W Queen Lane, Philadelphia, PA 19129, USA.
| |
Collapse
|
12
|
Vagal Control of Breathing Pattern after Midcervical Contusion in Rats. J Neurotrauma 2017; 34:734-745. [DOI: 10.1089/neu.2016.4645] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
|
13
|
Neuroprotective and Neurorestorative Processes after Spinal Cord Injury: The Case of the Bulbospinal Respiratory Neurons. Neural Plast 2016; 2016:7692602. [PMID: 27563469 PMCID: PMC4987469 DOI: 10.1155/2016/7692602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 06/29/2016] [Indexed: 11/18/2022] Open
Abstract
High cervical spinal cord injuries interrupt the bulbospinal respiratory pathways projecting to the cervical phrenic motoneurons resulting in important respiratory defects. In the case of a lateralized injury that maintains the respiratory drive on the opposite side, a partial recovery of the ipsilateral respiratory function occurs spontaneously over time, as observed in animal models. The rodent respiratory system is therefore a relevant model to investigate the neuroplastic and neuroprotective mechanisms that will trigger such phrenic motoneurons reactivation by supraspinal pathways. Since part of this recovery is dependent on the damaged side of the spinal cord, the present review highlights our current understanding of the anatomical neuroplasticity processes that are developed by the surviving damaged bulbospinal neurons, notably axonal sprouting and rerouting. Such anatomical neuroplasticity relies also on coordinated molecular mechanisms at the level of the axotomized bulbospinal neurons that will promote both neuroprotection and axon growth.
Collapse
|
14
|
ZHANG PENG, MA XUN. Effect of rutin on spinal cord injury through inhibition of the expression of MIP-2 and activation of MMP-9, and downregulation of Akt phosphorylation. Mol Med Rep 2015; 12:7554-60. [DOI: 10.3892/mmr.2015.4357] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 08/25/2015] [Indexed: 11/06/2022] Open
|