1
|
Michel-Flutot P, Cheng L, Thomas SJ, Lisi B, Schwartz H, Lam S, Lyttle M, Jaffe DA, Smith G, Li S, Wright MC, Lepore AC. PTEN inhibition promotes robust growth of bulbospinal respiratory axons and partial recovery of diaphragm function in a chronic model of cervical contusion spinal cord injury. Exp Neurol 2024; 378:114816. [PMID: 38789023 PMCID: PMC11200215 DOI: 10.1016/j.expneurol.2024.114816] [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: 01/10/2024] [Revised: 03/25/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024]
Abstract
High spinal cord injury (SCI) leads to persistent and debilitating compromise in respiratory function. Cervical SCI not only causes the death of phrenic motor neurons (PhMNs) that innervate the diaphragm, but also damages descending respiratory pathways originating in the rostral ventral respiratory group (rVRG) located in the brainstem, resulting in denervation and consequent silencing of spared PhMNs located caudal to injury. It is imperative to determine whether interventions targeting rVRG axon growth and respiratory neural circuit reconnection are efficacious in chronic cervical contusion SCI, given that the vast majority of individuals are chronically-injured and most cases of SCI involve contusion-type damage to the cervical region. We therefore employed a rat model of chronic cervical hemicontusion to test therapeutic manipulations aimed at reconstructing damaged rVRG-PhMN-diaphragm circuitry to achieve recovery of respiratory function. At a chronic time point post-injury, we systemically administered: an antagonist peptide directed against phosphatase and tensin homolog (PTEN), a central inhibitor of neuron-intrinsic axon growth potential; an antagonist peptide directed against receptor-type protein tyrosine phosphatase sigma (PTPσ), another important negative regulator of axon growth capacity; or a combination of these two peptides. PTEN antagonist peptide (PAP4) promoted partial recovery of diaphragm motor activity out to nine months post-injury (though this effect depended on the anesthetic regimen used during recording), while PTPσ peptide did not impact diaphragm function after cervical SCI. Furthermore, PAP4 promoted robust growth of descending bulbospinal rVRG axons caudal to the injury within the denervated portion of the PhMN pool, while PTPσ peptide did not affect rVRG axon growth at this location that is critical to control of diaphragmatic respiratory function. In conclusion, we find that, when PTEN inhibition is targeted at a chronic time point following cervical contusion, our non-invasive PAP4 strategy can successfully promote significant regrowth of damaged respiratory neural circuitry and also partial recovery of diaphragm motor function.
Collapse
Affiliation(s)
- Pauline Michel-Flutot
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Lan Cheng
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Samantha J Thomas
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Brianna Lisi
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Harrison Schwartz
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Sandy Lam
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Megan Lyttle
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - David A Jaffe
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - George Smith
- Department of Neuroscience, Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, PA 191405104, USA
| | - Shuxin Li
- Department of Neuroscience, Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, PA 191405104, USA
| | - Megan C Wright
- Department of Biology, Arcadia University, Glenside, PA 19038, USA
| | - Angelo C Lepore
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| |
Collapse
|
2
|
Olopade FE, Femi-Akinlosotu OM, Dauda O, Obiako J, Olopade JO, Shokunbi MT. Vanadium administration ameliorates cortical structural and functional changes in juvenile hydrocephalic mice. J Comp Neurol 2024; 532:e25578. [PMID: 38175813 DOI: 10.1002/cne.25578] [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: 06/03/2023] [Revised: 11/29/2023] [Accepted: 12/17/2023] [Indexed: 01/06/2024]
Abstract
Vanadium is a prevalent neurotoxic transition metal with therapeutic potentials in some neurological conditions. Hydrocephalus poses a major clinical burden in neurological practice in Africa. Its primary treatment (shunting) has complications, including infection and blockage; alternative drug-based therapies are therefore necessary. This study investigates the function and cytoarchitecture of motor and cerebellar cortices in juvenile hydrocephalic mice following treatment with varying doses of vanadium. Fifty juvenile mice were allocated into five groups (n = 10 each): controls, hydrocephalus-only, low- (0.15 mg/kg), moderate- (0.3 mg/kg), and high- (3.0 mg/kg) dose vanadium groups. Hydrocephalus was induced by the intracisternal injection of kaolin and sodium metavanadate administered by intraperitoneal injection 72hourly for 28 days. Neurobehavioral tests: open field, hanging wire, and pole tests, were carried out to assess locomotion, muscular strength, and motor coordination, respectively. The cerebral motor and the cerebellar cortices were processed for cresyl violet staining and immunohistochemistry for neurons (NeuN) and astrocytes (glial fibrillary acidic protein). Hydrocephalic mice exhibited body weight loss and behavioral deficits. Horizontal and vertical movements and latency to fall from hanging wire were significantly reduced, while latency to turn and descend the pole were prolonged in hydrocephalic mice, suggesting impaired motor ability; this was improved in vanadium-treated mice. Increased neuronal count, pyknotic cells, neurodegeneration and reactive astrogliosis were observed in the hydrocephalic mice. These were mostly mitigated in the vanadium-treated mice, except in the high-dose group where astrogliosis persisted. These results demonstrate a neuroprotective potential of vanadium administration in hydrocephalus. The molecular basis of these effects needs further exploration.
Collapse
Affiliation(s)
| | | | - Opeyemi Dauda
- Department of Anatomy, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Jane Obiako
- Department of Anatomy, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - James Olukayode Olopade
- Neuroscience Unit, Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, Nigeria
| | - Matthew Temitayo Shokunbi
- Department of Anatomy, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Division of Neurological Surgery, Department of Surgery, University of Ibadan, Ibadan, Nigeria
| |
Collapse
|
3
|
Michel-Flutot P, Cheng L, Thomas SJ, Lisi B, Schwartz H, Lam S, Lyttle M, Jaffe DA, Smith G, Li S, Wright MC, Lepore AC. PTEN inhibition promotes robust growth of bulbospinal respiratory axons and partial recovery of diaphragm function in a chronic model of cervical contusion spinal cord injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.10.575021. [PMID: 38260313 PMCID: PMC10802567 DOI: 10.1101/2024.01.10.575021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
High spinal cord injury (SCI) leads to persistent and debilitating compromise in respiratory function. Cervical SCI not only causes the death of phrenic motor neurons (PhMNs) that innervate the diaphragm, but also damages descending respiratory pathways originating in the rostral ventral respiratory group (rVRG) located in the brainstem, resulting in denervation and consequent silencing of spared PhMNs located caudal to injury. It is imperative to determine whether interventions targeting rVRG axon growth and respiratory neural circuit reconnection are efficacious in chronic cervical contusion SCI, given that the vast majority of individuals are chronically-injured and most cases of SCI involve contusion-type damage to the cervical region. We therefore employed a clinically-relevant rat model of chronic cervical hemicontusion to test therapeutic manipulations aimed at reconstructing damaged rVRG-PhMN-diaphragm circuitry to achieve recovery of respiratory function. At a chronic time point post-injury, we systemically administered: an antagonist peptide directed against phosphatase and tensin homolog (PTEN), a central inhibitor of neuron-intrinsic axon growth potential; an antagonist peptide directed against receptor-type protein tyrosine phosphatase sigma (PTPσ), another important negative regulator of axon growth capacity; or a combination of these two peptides. PTEN antagonist peptide (PAP4) promoted partial recovery of diaphragm motor activity out to nine months post-injury, while PTPσ peptide did not impact diaphragm function after cervical SCI. Furthermore, PAP4 promoted robust growth of descending bulbospinal rVRG axons caudal to the injury within the denervated portion of the PhMN pool, while PTPσ peptide did not affect rVRG axon growth at this location that is critical to control of diaphragmatic respiratory function. In conclusion, we find that, when PTEN inhibition is targeted at a chronic time point following cervical contusion that is most relevant to the SCI clinical population, our non-invasive PAP4 strategy can successfully promote significant regrowth of damaged respiratory neural circuitry and also partial recovery of diaphragm motor function. HIGHLIGHTS PTEN antagonist peptide promotes partial diaphragm function recovery in chronic cervical contusion SCI.PTPσ inhibitory peptide does not impact diaphragm function recovery in chronic cervical contusion SCI.PTEN antagonist peptide promotes growth of bulbospinal rVRG axons in chronic cervical contusion SCI.PTPσ peptide does not affect rVRG axon growth in chronic cervical contusion SCI.
Collapse
|
4
|
Fan B, Lu F, Du WJ, Chen J, An XG, Wang RF, Li W, Song YL, Zha DJ, Chen FQ. PTEN inhibitor bisperoxovanadium protects against noise-induced hearing loss. Neural Regen Res 2023; 18:1601-1606. [PMID: 36571368 PMCID: PMC10075117 DOI: 10.4103/1673-5374.358606] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Studies have shown that phosphatase and tensin homolog deleted on chromosome ten (PTEN) participates in the regulation of cochlear hair cell survival. Bisperoxovanadium protects against neurodegeneration by inhibiting PTEN expression. However, whether bisperoxovanadium can protect against noise-induced hearing loss and the underlying mechanism remains unclear. In this study, we established a mouse model of noise-induced hearing loss by exposure to 105 dB sound for 2 hours. We found that PTEN expression was increased in the organ of Corti, including outer hair cells, inner hair cells, and lateral wall tissues. Intraperitoneal administration of bisperoxovanadium decreased the auditory threshold and the loss of cochlear hair cells and inner hair cell ribbons. In addition, noise exposure decreased p-PI3K and p-Akt levels. Bisperoxovanadium preconditioning or PTEN knockdown upregulated the activity of PI3K-Akt. Bisperoxovanadium also prevented H2O2-induced hair cell death by reducing mitochondrial reactive oxygen species generation in cochlear explants. These findings suggest that bisperoxovanadium reduces noise-induced hearing injury and reduces cochlear hair cell loss.
Collapse
Affiliation(s)
- Bei Fan
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Fei Lu
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Wei-Jia Du
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Jun Chen
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Xiao-Gang An
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Ren-Feng Wang
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Wei Li
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Yong-Li Song
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Ding-Jun Zha
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Fu-Quan Chen
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| |
Collapse
|
5
|
Pearson A, Ortiz C, Eisenbaum M, Arrate C, Browning M, Mullan M, Bachmeier C, Crawford F, Ojo JO. Deletion of PTEN in microglia ameliorates chronic neuroinflammation following repetitive mTBI. Mol Cell Neurosci 2023; 125:103855. [PMID: 37084991 DOI: 10.1016/j.mcn.2023.103855] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/25/2023] [Accepted: 04/17/2023] [Indexed: 04/23/2023] Open
Abstract
Traumatic brain injury is a leading cause of morbidity and mortality in adults and children in developed nations. Following the primary injury, microglia, the resident innate immune cells of the CNS, initiate several inflammatory signaling cascades and pathophysiological responses that may persist chronically; chronic neuroinflammation following TBI has been closely linked to the development of neurodegeneration and neurological dysfunction. Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that have been shown to regulate several key mechanisms in the inflammatory response to TBI. Increasing evidence has shown that the modulation of the PI3K/AKT signaling pathway has the potential to influence the cellular response to inflammatory stimuli. However, directly targeting PI3K signaling poses several challenges due to its regulatory role in several cell survival pathways. We have previously identified that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN), the major negative regulator of PI3K/AKT signaling, is dysregulated following exposure to repetitive mild traumatic brain injury (r-mTBI). Moreover, this dysregulated PI3K/AKT signaling was correlated with chronic microglial-mediated neuroinflammation. Therefore, we interrogated microglial-specific PTEN as a therapeutic target in TBI by generating a microglial-specific, Tamoxifen inducible conditional PTEN knockout model using a CX3CR1 Cre recombinase mouse line PTENfl/fl/CX3CR1+/CreERT2 (mcg-PTENcKO), and exposed them to our 20-hit r-mTBI paradigm. Animals were treated with tamoxifen at 76 days post-last injury, and the effects of microglia PTEN deletion on immune-inflammatory responses were assessed at 90-days post last injury. We observed that the deletion of microglial PTEN ameliorated the proinflammatory response to repetitive brain trauma, not only reducing chronic microglial activation and proinflammatory cytokine production but also rescuing TBI-induced reactive astrogliosis, demonstrating that these effects extended beyond microglia alone. Additionally, we observed that the pharmacological inhibition of PTEN with BpV(HOpic) ameliorated the LPS-induced activation of microglial NFκB signaling in vitro. Together, these data provide support for the role of PTEN as a regulator of chronic neuroinflammation following repetitive mild TBI.
Collapse
Affiliation(s)
- Andrew Pearson
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom.
| | - Camila Ortiz
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom
| | - Max Eisenbaum
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom
| | - Clara Arrate
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA
| | | | - Michael Mullan
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom
| | - Corbin Bachmeier
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom
| | - Fiona Crawford
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom; James A. Haley Veterans' Hospital, 13000 Bruce B Downs Blvd, Tampa, FL 33612, USA
| | - Joseph O Ojo
- The Roskamp Institute, 2040 Whitfield Avenue, Sarasota, FL 34243, USA; The Open University, Walton Hall, Kents Hill, Milton Keynes MK7 6AA, United Kingdom
| |
Collapse
|
6
|
Femi-Akinlosotu OM, Olopade FE, Obiako J, Olopade JO, Shokunbi MT. Vanadium improves memory and spatial learning and protects the pyramidal cells of the hippocampus in juvenile hydrocephalic mice. Front Neurol 2023; 14:1116727. [PMID: 36846142 PMCID: PMC9947794 DOI: 10.3389/fneur.2023.1116727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 01/23/2023] [Indexed: 02/11/2023] Open
Abstract
Background Hydrocephalus is a neurological condition known to cause learning and memory disabilities due to its damaging effect on the hippocampal neurons, especially pyramidal neurons. Vanadium at low doses has been observed to improve learning and memory abilities in neurological disorders but it is uncertain whether such protection will be provided in hydrocephalus. We investigated the morphology of hippocampal pyramidal neurons and neurobehavior in vanadium-treated and control juvenile hydrocephalic mice. Methods Hydrocephalus was induced by intra-cisternal injection of sterile-kaolin into juvenile mice which were then allocated into 4 groups of 10 pups each, with one group serving as an untreated hydrocephalic control while others were treated with 0.15, 0.3 and 3 mg/kg i.p of vanadium compound respectively, starting 7 days post-induction for 28 days. Non-hydrocephalic sham controls (n = 10) were sham operated without any treatment. Mice were weighed before dosing and sacrifice. Y-maze, Morris Water Maze and Novel Object Recognition tests were carried out before the sacrifice, the brains harvested, and processed for Cresyl Violet and immunohistochemistry for neurons (NeuN) and astrocytes (GFAP). The pyramidal neurons of the CA1 and CA3 regions of the hippocampus were assessed qualitatively and quantitatively. Data were analyzed using GraphPad prism 8. Results Escape latencies of vanadium-treated groups were significantly shorter (45.30 ± 26.30 s, 46.50 ± 26.35 s, 42.99 ± 18.44 s) than untreated group (62.06 ± 24.02 s) suggesting improvements in learning abilities. Time spent in the correct quadrant was significantly shorter in the untreated group (21.19 ± 4.15 s) compared to control (34.15 ± 9.44 s) and 3 mg/kg vanadium-treated group (34.35 ± 9.74 s). Recognition index and mean % alternation were lowest in untreated group (p = 0.0431, p=0.0158) suggesting memory impairments, with insignificant improvements in vanadium-treated groups. NeuN immuno-stained CA1 revealed loss of apical dendrites of the pyramidal cells in untreated hydrocephalus group relative to control and a gradual reversal attempt in the vanadium-treated groups. Astrocytic activation (GFAP stain) in the untreated hydrocephalus group were attenuated in the vanadium-treated groups under the GFAP stain. Pyknotic index in CA1 pyramidal layer of untreated (18.82 ± 2.59) and 0.15mg/kg vanadium-treated groups (18.14 ± 5.92) were significantly higher than control (11.11 ± 0.93; p = 0.0205, p = 0.0373) while there was no significant difference in CA3 pyknotic index across all groups. Conclusion Our results suggest that vanadium has a dose-dependent protective effect on the pyramidal cells of the hippocampus and on memory and spatial learning functions in juvenile hydrocephalic mice.
Collapse
Affiliation(s)
| | - Funmilayo Eniola Olopade
- Developmental Neurobiology Laboratory, Department of Anatomy, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Jane Obiako
- Developmental Neurobiology Laboratory, Department of Anatomy, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - James Olukayode Olopade
- Neuroscience Unit, Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, Nigeria
| | - Matthew Temitayo Shokunbi
- Developmental Neurobiology Laboratory, Department of Anatomy, College of Medicine, University of Ibadan, Ibadan, Nigeria,Division of Neurological Surgery, Department of Surgery, University of Ibadan, Ibadan, Nigeria,*Correspondence: Matthew Temitayo Shokunbi ✉
| |
Collapse
|
7
|
Patent Highlights June–July 2022. Pharm Pat Anal 2022; 12:5-11. [PMID: 36511078 DOI: 10.4155/ppa-2022-0043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.
Collapse
|
8
|
Axonal Regeneration: Underlying Molecular Mechanisms and Potential Therapeutic Targets. Biomedicines 2022; 10:biomedicines10123186. [PMID: 36551942 PMCID: PMC9775075 DOI: 10.3390/biomedicines10123186] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/21/2022] [Accepted: 12/01/2022] [Indexed: 12/13/2022] Open
Abstract
Axons in the peripheral nervous system have the ability to repair themselves after damage, whereas axons in the central nervous system are unable to do so. A common and important characteristic of damage to the spinal cord, brain, and peripheral nerves is the disruption of axonal regrowth. Interestingly, intrinsic growth factors play a significant role in the axonal regeneration of injured nerves. Various factors such as proteomic profile, microtubule stability, ribosomal location, and signalling pathways mark a line between the central and peripheral axons' capacity for self-renewal. Unfortunately, glial scar development, myelin-associated inhibitor molecules, lack of neurotrophic factors, and inflammatory reactions are among the factors that restrict axonal regeneration. Molecular pathways such as cAMP, MAPK, JAK/STAT, ATF3/CREB, BMP/SMAD, AKT/mTORC1/p70S6K, PI3K/AKT, GSK-3β/CLASP, BDNF/Trk, Ras/ERK, integrin/FAK, RhoA/ROCK/LIMK, and POSTN/integrin are activated after nerve injury and are considered significant players in axonal regeneration. In addition to the aforementioned pathways, growth factors, microRNAs, and astrocytes are also commendable participants in regeneration. In this review, we discuss the detailed mechanism of each pathway along with key players that can be potentially valuable targets to help achieve quick axonal healing. We also identify the prospective targets that could help close knowledge gaps in the molecular pathways underlying regeneration and shed light on the creation of more powerful strategies to encourage axonal regeneration after nervous system injury.
Collapse
|
9
|
Noori T, Sahebgharani M, Sureda A, Sobarzo-Sanchez E, Fakhri S, Shirooie S. Targeting PI3K by Natural Products: A Potential Therapeutic Strategy for Attention-deficit Hyperactivity Disorder. Curr Neuropharmacol 2022; 20:1564-1578. [PMID: 35043762 PMCID: PMC9881086 DOI: 10.2174/1570159x20666220119125040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 01/02/2022] [Accepted: 01/12/2022] [Indexed: 11/22/2022] Open
Abstract
Attention-Deficit Hyperactivity Disorder (ADHD) is a highly prevalent childhood psychiatric disorder. In general, a child with ADHD has significant attention problems with difficulty concentrating on a subject and is generally associated with impulsivity and excessive activity. The etiology of ADHD in most patients is unknown, although it is considered to be a multifactorial disease caused by a combination of genetics and environmental factors. Diverse factors, such as the existence of mental, nutritional, or general health problems during childhood, as well as smoking and alcohol drinking during pregnancy, are related to an increased risk of ADHD. Behavioral and psychological characteristics of ADHD include anxiety, mood disorders, behavioral disorders, language disorders, and learning disabilities. These symptoms affect individuals, families, and communities, negatively altering educational and social results, strained parent-child relationships, and increased use of health services. ADHD may be associated with deficits in inhibitory frontostriatal noradrenergic neurons on lower striatal structures that are predominantly driven by dopaminergic neurons. Phosphoinositide 3-kinases (PI3Ks) are a conserved family of lipid kinases that control a number of cellular processes, including cell proliferation, differentiation, migration, insulin metabolism, and apoptosis. Since PI3K plays an important role in controlling the noradrenergic neuron, it opens up new insights into research on ADHD and other developmental brain diseases. This review presents evidence for the potential usefulness of PI3K and its modulators as a potential treatment for ADHD.
Collapse
Affiliation(s)
- Tayebeh Noori
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Mousa Sahebgharani
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Antoni Sureda
- Research Group on Community Nutrition and Oxidative Stress (NUCOX) and Health Research Institute of Balearic Islands (IdISBa), University of Balearic Islands-IUNICS, Palma de MallorcaE-07122, Balearic Islands, Spain;,CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III (ISCIII), 28029 Madrid, Spain
| | - Eduardo Sobarzo-Sanchez
- Instituto de Investigación y Postgrado, Facultad de Ciencias de la Salud, Universidad Central de Chile, Chile;,Department of Organic Chemistry, Faculty of Pharmacy, University of Santiago de Compostela, Santiago, Spain
| | - Sajad Fakhri
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Samira Shirooie
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran;,Address correspondence to this author at the Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran; E-mail:
| |
Collapse
|
10
|
Nieuwenhuis B, Eva R. Promoting axon regeneration in the central nervous system by increasing PI3-kinase signaling. Neural Regen Res 2021; 17:1172-1182. [PMID: 34782551 PMCID: PMC8643051 DOI: 10.4103/1673-5374.327324] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Much research has focused on the PI3-kinase and PTEN signaling pathway with the aim to stimulate repair of the injured central nervous system. Axons in the central nervous system fail to regenerate, meaning that injuries or diseases that cause loss of axonal connectivity have life-changing consequences. In 2008, genetic deletion of PTEN was identified as a means of stimulating robust regeneration in the optic nerve. PTEN is a phosphatase that opposes the actions of PI3-kinase, a family of enzymes that function to generate the membrane phospholipid PIP3 from PIP2 (phosphatidylinositol (3,4,5)-trisphosphate from phosphatidylinositol (4,5)-bisphosphate). Deletion of PTEN therefore allows elevated signaling downstream of PI3-kinase, and was initially demonstrated to promote axon regeneration by signaling through mTOR. More recently, additional mechanisms have been identified that contribute to the neuron-intrinsic control of regenerative ability. This review describes neuronal signaling pathways downstream of PI3-kinase and PIP3, and considers them in relation to both developmental and regenerative axon growth. We briefly discuss the key neuron-intrinsic mechanisms that govern regenerative ability, and describe how these are affected by signaling through PI3-kinase. We highlight the recent finding of a developmental decline in the generation of PIP3 as a key reason for regenerative failure, and summarize the studies that target an increase in signaling downstream of PI3-kinase to facilitate regeneration in the adult central nervous system. Finally, we discuss obstacles that remain to be overcome in order to generate a robust strategy for repairing the injured central nervous system through manipulation of PI3-kinase signaling.
Collapse
Affiliation(s)
- Bart Nieuwenhuis
- John van Geest Center for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Richard Eva
- John van Geest Center for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| |
Collapse
|
11
|
Wang J, Tierney L, Mann R, Lonsway T, Walker CL. Bisperoxovanadium promotes motor neuron survival and neuromuscular innervation in amyotrophic lateral sclerosis. Mol Brain 2021; 14:155. [PMID: 34635126 PMCID: PMC8507234 DOI: 10.1186/s13041-021-00867-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/02/2021] [Indexed: 12/21/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common motor neuron (MN) disease, with no present cure. The progressive loss of MNs is the hallmark of ALS. We have previously shown the therapeutic effects of the phosphatase and tensin homolog (PTEN) inhibitor, potassium bisperoxo (picolinato) vanadium (bpV[pic]), in models of neurological injury and demonstrated significant neuroprotective effects on MN survival. However, accumulating evidence suggests PTEN is detrimental for MN survival in ALS. Therefore, we hypothesized that treating the mutant superoxide dismutase 1 G93A (mSOD1G93A) mouse model of ALS during motor neuron degeneration and an in vitro model of mSOD1G93A motor neuron injury with bpV(pic) would prevent motor neuron loss. To test our hypothesis, we treated mSOD1G93A mice intraperitoneally daily with 400 μg/kg bpV(pic) from 70 to 90 days of age. Immunolabeled MNs and microglial reactivity were analyzed in lumbar spinal cord tissue, and bpV(pic) treatment significantly ameliorated ventral horn motor neuron loss in mSOD1G93A mice (p = 0.003) while not significantly altering microglial reactivity (p = 0.701). Treatment with bpV(pic) also significantly increased neuromuscular innervation (p = 0.018) but did not affect muscle atrophy. We also cultured motor neuron-like NSC-34 cells transfected with a plasmid to overexpress mutant SOD1G93A and starved them in serum-free medium for 24 h with and without bpV(pic) and downstream inhibitor of Akt signaling, LY294002. In vitro, bpV(pic) improved neuronal viability, and Akt inhibition reversed this protective effect (p < 0.05). In conclusion, our study indicates systemic bpV(pic) treatment could be a valuable neuroprotective therapy for ALS.
Collapse
Affiliation(s)
- Junmei Wang
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN, 46202, USA
| | - Lydia Tierney
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN, 46202, USA
| | - Ranjeet Mann
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN, 46202, USA
| | - Thomas Lonsway
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN, 46202, USA
| | - Chandler L Walker
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN, 46202, USA. .,Neuromuscular Research Group, Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, IN, 46202, USA.
| |
Collapse
|
12
|
Bhowmick S, Abdul-Muneer PM. PTEN Blocking Stimulates Corticospinal and Raphespinal Axonal Regeneration and Promotes Functional Recovery After Spinal Cord Injury. J Neuropathol Exp Neurol 2021; 80:169-181. [PMID: 33367790 DOI: 10.1093/jnen/nlaa147] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The long-term disabilities associated with spinal cord injury (SCI) are primarily due to the absence of robust neuronal regeneration and functional plasticity. The inability of the axon to regenerate after SCI is contributed by several intrinsic factors that trigger a cascade of molecular growth program and modulates axonal sprouting. Phosphatase and tensin homolog (PTEN) is one of the intrinsic factors contributing to growth failure after SCI, however, the underlying mechanism is not well known. Here, we developed a novel therapeutic approach for treating SCI by suppressing the action of PTEN in a mouse model of hemisection SCI. We have used a novel peptide, PTEN antagonistic peptide (PAP) to block the critical domains of PTEN to demonstrate its ability to potentially promote axon growth. PAP treatment not only enhanced regeneration of corticospinal axons into the caudal spinal cord but also promoted the regrowth of descending serotonergic axons in SCI mice. Furthermore, expression levels of p-mTOR, p-S6, p-Akt, p-Erk, p-GSK, p-PI3K downstream of PTEN signaling pathway were increased significantly in the spinal cord of SCI mice systemically treated with PAP than control TAT peptide-treated mice. Our novel strategy of administering deliverable compounds postinjury may facilitate translational feasibility for central nervous system injury.
Collapse
Affiliation(s)
- Saurav Bhowmick
- From the Laboratory of CNS Injury and Molecular Therapy, JFK Neuroscience Institute, Hackensack Meridian Health JFK University Medical Center, Edison, New Jersey
| | - P M Abdul-Muneer
- Department of Neurology, Hackensack Meridian School of Medicine, Nutley, New Jersey
| |
Collapse
|
13
|
Cheng L, Sami A, Ghosh B, Goudsward HJ, Smith GM, Wright MC, Li S, Lepore AC. Respiratory axon regeneration in the chronically injured spinal cord. Neurobiol Dis 2021; 155:105389. [PMID: 33975016 DOI: 10.1016/j.nbd.2021.105389] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/19/2021] [Accepted: 05/05/2021] [Indexed: 02/01/2023] Open
Abstract
Promoting the combination of robust regeneration of damaged axons and synaptic reconnection of these growing axon populations with appropriate neuronal targets represents a major therapeutic goal following spinal cord injury (SCI). A key impediment to achieving this important aim includes an intrinsic inability of neurons to extend axons in adult CNS, particularly in the context of the chronically-injured spinal cord. We tested whether an inhibitory peptide directed against phosphatase and tensin homolog (PTEN: a central inhibitor of neuron-intrinsic axon growth potential) could restore inspiratory diaphragm function by reconnecting critical respiratory neural circuitry in a rat model of chronic cervical level 2 (C2) hemisection SCI. We found that systemic delivery of PTEN antagonist peptide 4 (PAP4) starting at 8 weeks after C2 hemisection promoted substantial, long-distance regeneration of injured bulbospinal rostral Ventral Respiratory Group (rVRG) axons into and through the lesion and back toward phrenic motor neurons (PhMNs) located in intact caudal C3-C5 spinal cord. Despite this robust rVRG axon regeneration, PAP4 stimulated only minimal recovery of diaphragm function. Furthermore, re-lesion through the hemisection site completely removed PAP4-induced functional improvement, demonstrating that axon regeneration through the lesion was responsible for this partial functional recovery. Interestingly, there was minimal formation of putative excitatory monosynaptic connections between regrowing rVRG axons and PhMN targets, suggesting that (1) limited rVRG-PhMN synaptic reconnectivity was responsible at least in part for the lack of a significant functional effect, (2) chronically-injured spinal cord presents an obstacle to achieving synaptogenesis between regenerating axons and post-synaptic targets, and (3) addressing this challenge is a potentially-powerful strategy to enhance therapeutic efficacy in the chronic SCI setting. In conclusion, our study demonstrates a non-invasive and transient pharmacological approach in chronic SCI to repair the critically-important neural circuitry controlling diaphragmatic respiratory function, but also sheds light on obstacles to circuit plasticity presented by the chronically-injured spinal cord.
Collapse
Affiliation(s)
- Lan Cheng
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Armin Sami
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Biswarup Ghosh
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Hannah J Goudsward
- Department of Biology, Arcadia University, 450 S. Easton Rd., 220 Boyer Hall, Glenside, PA 19038, USA
| | - George M Smith
- Department of Neuroscience, Shriners Hospitals for Pediatric Research Center, Temple University School of Medicine, 3500 North Broad Street, Philadelphia, PA 19140-5104, USA
| | - Megan C Wright
- Department of Biology, Arcadia University, 450 S. Easton Rd., 220 Boyer Hall, Glenside, PA 19038, USA
| | - Shuxin Li
- Department of Neuroscience, Shriners Hospitals for Pediatric Research Center, Temple University School of Medicine, 3500 North Broad Street, Philadelphia, PA 19140-5104, USA
| | - Angelo C Lepore
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| |
Collapse
|
14
|
Lv SQ, Wu W. ISP and PAP4 peptides promote motor functional recovery after peripheral nerve injury. Neural Regen Res 2021; 16:1598-1605. [PMID: 33433490 PMCID: PMC8323685 DOI: 10.4103/1673-5374.294565] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Both intracellular sigma peptide (ISP) and phosphatase and tensin homolog agonist protein (PAP4) promote nerve regeneration and motor functional recovery after spinal cord injury. However, the role of these two small peptides in peripheral nerve injury remains unclear. A rat model of brachial plexus injury was established by crush of the C6 ventral root. The rats were then treated with subcutaneous injection of PAP4 (497 µg/d, twice per day) or ISP (11 µg/d, once per day) near the injury site for 21 successive days. After ISP and PAP treatment, the survival of motoneurons was increased, the number of regenerated axons and neuromuscular junctions was increased, muscle atrophy was reduced, the electrical response of the motor units was enhanced and the motor function of the injured upper limbs was greatly improved in rats with brachial plexus injury. These findings suggest that ISP and PAP4 promote the recovery of motor function after peripheral nerve injury in rats. The animal care and experimental procedures were approved by the Laboratory Animal Ethics Committee of Jinan University of China (approval No. 20111008001) in 2011.
Collapse
Affiliation(s)
- Shi-Qin Lv
- Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, Guangdong Province, China
| | - Wutian Wu
- Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, Guangdong Province; Re-Stem Biotechnology Co., Ltd., Suzhou, Jiangsu Province, China
| |
Collapse
|
15
|
Moses C, Hodgetts SI, Nugent F, Ben-Ary G, Park KK, Blancafort P, Harvey AR. Transcriptional repression of PTEN in neural cells using CRISPR/dCas9 epigenetic editing. Sci Rep 2020; 10:11393. [PMID: 32647121 PMCID: PMC7347541 DOI: 10.1038/s41598-020-68257-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022] Open
Abstract
After damage to the adult mammalian central nervous system (CNS), surviving neurons have limited capacity to regenerate and restore functional connectivity. Conditional genetic deletion of PTEN results in robust CNS axon regrowth, while PTEN repression with short hairpin RNA (shRNA) improves regeneration but to a lesser extent, likely due to suboptimal PTEN mRNA knockdown using this approach. Here we employed the CRISPR/dCas9 system to repress PTEN transcription in neural cells. We targeted the PTEN proximal promoter and 5' untranslated region with dCas9 fused to the repressor protein Krüppel-associated box (KRAB). dCas9-KRAB delivered in a lentiviral vector with one CRISPR guide RNA (gRNA) achieved potent and specific PTEN repression in human cell line models and neural cells derived from human iPSCs, and induced histone (H)3 methylation and deacetylation at the PTEN promoter. The dCas9-KRAB system outperformed a combination of four shRNAs targeting the PTEN transcript, a construct previously used in CNS injury models. The CRISPR system also worked more effectively than shRNAs for Pten repression in rat neural crest-derived PC-12 cells, and enhanced neurite outgrowth after nerve growth factor stimulation. PTEN silencing with CRISPR/dCas9 epigenetic editing may provide a new option for promoting axon regeneration and functional recovery after CNS trauma.
Collapse
Affiliation(s)
- C Moses
- School of Human Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia
- Cancer Epigenetics Laboratory, The Harry Perkins Institute of Medical Research, 6 Verdun Street, Nedlands, WA, 6009, Australia
| | - S I Hodgetts
- School of Human Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia
- Perron Institute for Neurological and Translational Science, 8 Verdun Street, Nedlands, WA, 6009, Australia
| | - F Nugent
- Cancer Epigenetics Laboratory, The Harry Perkins Institute of Medical Research, 6 Verdun Street, Nedlands, WA, 6009, Australia
- School of Molecular Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia
| | - G Ben-Ary
- School of Human Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia
| | - K K Park
- Department of Neurological Surgery, Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - P Blancafort
- School of Human Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.
- Cancer Epigenetics Laboratory, The Harry Perkins Institute of Medical Research, 6 Verdun Street, Nedlands, WA, 6009, Australia.
- Greehey Children's Cancer Research Institute, UT Health San Antonio, 8403 Floyd Curl Drive, San Antonio, TX, 78229, USA.
| | - A R Harvey
- School of Human Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.
- Perron Institute for Neurological and Translational Science, 8 Verdun Street, Nedlands, WA, 6009, Australia.
| |
Collapse
|
16
|
Li T, Gu J, Yang O, Wang J, Wang Y, Kong J. Bone Marrow Mesenchymal Stem Cell-Derived Exosomal miRNA-29c Decreases Cardiac Ischemia/Reperfusion Injury Through Inhibition of Excessive Autophagy via the PTEN/Akt/mTOR Signaling Pathway. Circ J 2020; 84:1304-1311. [PMID: 32581152 DOI: 10.1253/circj.cj-19-1060] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Cardiac ischemia/reperfusion (I/R) injury will cause a large amount of cardiomyocyte loss and cascade reactions such as apoptosis, mitochondrial dysfunction, and excessive autophagy. Mesenchymal stem cells (MSCs) are promising therapeutic tools to replace damaged cardiomyocytes, but the underlying mechanism is still unknown.Methods and Results:Exosomes contain many microRNAs and protein, which are believed to have multiple biological functions. This study explored the role of bone marrow MSCs (BMMSCs)-derived exosomes under different oxidation levels in heart protection and miRNA-related mechanisms. Exosomes extracted from BMMSCs contained a high level of miR-29c, and its expression level changed after cells were treated under hypoxia/reoxygenation (H/R) conditions. In vivo I/R experiments also confirmed an expression change of miR-29c, and PTEN-Akt-mTOR is one of the predominant pathways that regulate autophagic change during this process. CONCLUSIONS This study highlighted the role of miR-29c in regulating autophagy under cardiac I/R injury, which also extended existing mechanisms of a stem cell and its derivative to explore potential therapeutic interventions in ischemic heart diseases.
Collapse
Affiliation(s)
- Te Li
- Department of Geriatrics, The First Hospital of Jilin University
| | | | - Ou Yang
- Department of Geriatrics, The First Hospital of Jilin University
| | - Jianmeng Wang
- Department of Geriatrics, The First Hospital of Jilin University
| | - Yonggang Wang
- Department of Cardiovascular Center, The First Hospital of Jilin University
| | - Jian Kong
- Department of Geriatrics, The First Hospital of Jilin University
| |
Collapse
|
17
|
Liu J, Li K, Huang K, Yang C, Huang Z, Zhao X, Song S, Pang T, Zhou J, Wang Y, Wang C, Tang Y. Acellularized spinal cord scaffolds incorporating bpV(pic)/PLGA microspheres promote axonal regeneration and functional recovery after spinal cord injury. RSC Adv 2020; 10:18677-18686. [PMID: 35518337 PMCID: PMC9053942 DOI: 10.1039/d0ra02661a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/07/2020] [Indexed: 01/20/2023] Open
Abstract
Spinal cord injury (SCI) is a traumatic injury to the central nervous system (CNS) with a high rate of disability and a low capability of self-recovery. Phosphatase and tensin homolog (PTEN) inhibition by pharmacological blockade with bisperoxovanadium (pic) (bpV(pic)) has been reported to increase AKT/mTOR activity and induce robust axonal elongation and regeneration. However, the therapeutic effect of bpV(pic) in treating SCI is limited due to the lack of efficient delivery approaches. In this study, a composite scaffold consisting of an acellular spinal cord (ASC) scaffold and incorporated bpV(pic) loaded poly (lactic-co-glycolic acid) (PLGA) microspheres was developed, in order to improve the therapeutic effect of bpV(pic) on SCI. The inhibition of PTEN activity and activation of the mTORC1/AKT pathway, the axonal regeneration and the markers of apoptosis were analyzed via western blot and immunofluorescence in vitro. The bpV(pic)/PLGA/ASC scaffolds showed excellent biocompatibility and promoted the viability of neural stem cells and axonal growth in vitro. Implantation of the composite scaffold into rats with hemi-sectioned SCI resulted in increased axonal regeneration and functional recovery in vivo. Besides, bpV(pic) inhibited the phosphorylation of PTEN and activated the PI3K/mTOR signaling pathway. The successful construction of the composite scaffold improves the therapeutic effect of bpV(pic) on SCI.
Collapse
Affiliation(s)
- Jia Liu
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Kai Li
- Academy of Orthopedics, Guangdong Province, The Third Affiliated Hospital of Southern Medical UniversityGuangzhouGuangdong510000China
| | - Ke Huang
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Chengliang Yang
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Zhipeng Huang
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Xingchang Zhao
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Shiqiang Song
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Taisen Pang
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| | - Jing Zhou
- Department of Anatomy, Youjiang Medical College for NationalitiesBaiseGuangxi533000China
| | - Yuhai Wang
- Academy of Orthopedics, People's Hospital of Ningxia Hui Autonomous RegionNingxia502213China
| | - Chong Wang
- School of Mechanical Engineering, Dongguan University of TechnologyNo. 1 University Road, Songshan LakeDongguanGuangdong523808P. R. China+86-1341-6885162
| | - Yujin Tang
- Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities18 Zhongshan II RoadBaiseGuangxi533000China+86-0776-2833076
| |
Collapse
|
18
|
Borges GA, Webber LP, M Marques AE, Guerra EN, Castilho RM, Squarize CH. Pharmacological PTEN inhibition: potential clinical applications and effects in tissue regeneration. Regen Med 2020; 15:1329-1344. [PMID: 32223643 DOI: 10.2217/rme-2019-0065] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Although the human body can heal, it takes time, and slow healing and chronic wounds often occur. Thus, identifying novel therapies to aid regeneration is needed. Here, we conducted a systematic review following the Preferred Reporting Items for Systematic Reviews guidelines and assessed preclinical studies on phosphatase and tensin homolog (PTEN) inhibitors and their effects on tissue repair and regeneration. In conditions associated with neurodegeneration, tissue injury and ischemia, the PTEN-regulated PI3K/AKT signaling pathway is activated. The use of PTEN inhibitors resulted in better tissue response by reducing the healing time and lesion sizes or inducing neuronal regeneration. Notably, all studies included in this systematic review indicated that pharmacological inhibition of PTEN enhanced the repair process of the eye, lung, muscle and nervous system.
Collapse
Affiliation(s)
- Gabriel A Borges
- Laboratory of Epithelial Biology, Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.,Laboratory of Oral Histopathology, Health Sciences Faculty, University of Brasília, Brasília, Brazil
| | - Liana P Webber
- Laboratory of Epithelial Biology, Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA
| | - Ana Elizia M Marques
- Laboratory of Epithelial Biology, Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.,Laboratory of Oral Histopathology, Health Sciences Faculty, University of Brasília, Brasília, Brazil
| | - Eliete Ns Guerra
- Laboratory of Epithelial Biology, Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.,Laboratory of Oral Histopathology, Health Sciences Faculty, University of Brasília, Brasília, Brazil
| | - Rogerio M Castilho
- Laboratory of Epithelial Biology, Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.,The Michigan Medicine Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA
| | - Cristiane H Squarize
- Laboratory of Epithelial Biology, Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.,The Michigan Medicine Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA
| |
Collapse
|
19
|
Microglia Mediated Neuroinflammation: Focus on PI3K Modulation. Biomolecules 2020; 10:biom10010137. [PMID: 31947676 PMCID: PMC7022557 DOI: 10.3390/biom10010137] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 12/21/2022] Open
Abstract
Immune activation in the central nervous system involves mostly microglia in response to pathogen invasion or tissue damage, which react, promoting a self-limiting inflammatory response aimed to restore homeostasis. However, prolonged, uncontrolled inflammation may result in the production by microglia of neurotoxic factors that lead to the amplification of the disease state and tissue damage. In particular, specific inducers of inflammation associated with neurodegenerative diseases activate inflammatory processes that result in the production of a number of mediators and cytokines that enhance neurodegenerative processes. Phosphoinositide 3-kinases (PI3Ks) constitute a family of enzymes regulating a wide range of activity, including signal transduction. Recent studies have focused attention on the intracellular role of PI3K and its contribution to neurodegenerative processes. This review illustrates and discusses recent findings about the role of this signaling pathway in the modulation of microglia neuroinflammatory responses linked to neurodegeneration. Finally, we discuss the modulation of PI3K as a potential therapeutic approach helpful for developing innovative therapeutic strategies in neurodegenerative diseases.
Collapse
|
20
|
Guo S, Perets N, Betzer O, Ben-Shaul S, Sheinin A, Michaelevski I, Popovtzer R, Offen D, Levenberg S. Intranasal Delivery of Mesenchymal Stem Cell Derived Exosomes Loaded with Phosphatase and Tensin Homolog siRNA Repairs Complete Spinal Cord Injury. ACS NANO 2019; 13:10015-10028. [PMID: 31454225 DOI: 10.1021/acsnano.9b01892] [Citation(s) in RCA: 229] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Individuals with spinal cord injury (SCI) usually suffer from permanent neurological deficits, while spontaneous recovery and therapeutic efficacy are limited. Here, we demonstrate that when given intranasally, exosomes derived from mesenchymal stem cells (MSC-Exo) could pass the blood brain barrier and migrate to the injured spinal cord area. Furthermore, MSC-Exo loaded with phosphatase and tensin homolog small interfering RNA (ExoPTEN) could attenuate the expression of PTEN in the injured spinal cord region following intranasal administrations. In addition, the loaded MSC-Exo considerably enhanced axonal growth and neovascularization, while reducing microgliosis and astrogliosis. The intranasal ExoPTEN therapy could also partly improve structural and electrophysiological function and, most importantly, significantly elicited functional recovery in rats with complete SCI. The results imply that intranasal ExoPTEN may be used clinically to promote recovery for SCI individuals.
Collapse
Affiliation(s)
- Shaowei Guo
- Department of Biomedical Engineering , Technion-Israel Institute of Technology , Haifa 3200003 , Israel
- The First Affiliated Hospital , Shantou University Medical College , Shantou 515041 , China
| | | | - Oshra Betzer
- Faculty of Engineering and the Institute of Nanotechnology & Advanced Materials , Bar-Ilan University , Ramat Gan 5290002 , Israel
| | - Shahar Ben-Shaul
- Department of Biomedical Engineering , Technion-Israel Institute of Technology , Haifa 3200003 , Israel
| | | | - Izhak Michaelevski
- Department of Molecular Biology , Ariel University , Ariel 40700 , Israel
| | - Rachela Popovtzer
- Faculty of Engineering and the Institute of Nanotechnology & Advanced Materials , Bar-Ilan University , Ramat Gan 5290002 , Israel
| | | | - Shulamit Levenberg
- Department of Biomedical Engineering , Technion-Israel Institute of Technology , Haifa 3200003 , Israel
| |
Collapse
|
21
|
Boosani CS, Gunasekar P, Agrawal DK. An update on PTEN modulators - a patent review. Expert Opin Ther Pat 2019; 29:881-889. [PMID: 31530116 DOI: 10.1080/13543776.2019.1669562] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Introduction: A multitude of cellular and physiological functions have been attributed to the biological activity of PTEN (Phosphatase and tensin homolog) such as inhibiting angiogenesis, promoting apoptosis, preventing cell proliferation, and maintaining cellular homeostasis. Based on whether cell growth is needed to be initiated or to be inhibited, enhancing PTEN expression or seeking to inhibit it was pursued. Areas covered: Here the authors provide recent updates to their previous publication on 'PTEN modulators: A patent review', and discuss on new specificities that affirm the therapeutic potential of PTEN in promoting neuro-regeneration, stem cell regeneration, autophagy, bone and cartilage regeneration. Also, targeting PTEN appears to be effective in developing new treatment strategies for Parkinson's disease, Alzheimer's disease, macular degeneration, immune disorders, asthma, arthritis, lupus, Crohn's disease, and several cancer types. Expert opinion: PTEN mainly inhibits the PI3k/Akt pathway. However, the PI3k/Akt pathway can be activated by other signaling proteins. Thus, novel treatment strategies that can regulate PTEN alone, or combinational treatment approaches that can induce PTEN and simultaneously affect downstream mediators in the PI3K/Akt pathway, are needed, which were not investigated in detail. Commercial interests associated with molecules that regulate PTEN are discussed here, along with limitations and new possibilities to improve them.
Collapse
Affiliation(s)
- Chandra S Boosani
- Department of Translational Research, Western University of Health Sciences , Pomona , CA , USA
| | - Palanikumar Gunasekar
- Department of Clinical & Translational Science, Creighton University School of Medicine , Omaha , NE , USA
| | - Devendra K Agrawal
- Department of Translational Research, Western University of Health Sciences , Pomona , CA , USA
| |
Collapse
|
22
|
Nimodipine-Dependent Protection of Schwann Cells, Astrocytes and Neuronal Cells from Osmotic, Oxidative and Heat Stress Is Associated with the Activation of AKT and CREB. Int J Mol Sci 2019; 20:ijms20184578. [PMID: 31527507 PMCID: PMC6770698 DOI: 10.3390/ijms20184578] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/06/2019] [Accepted: 09/14/2019] [Indexed: 02/08/2023] Open
Abstract
Clinical and experimental data assumed a neuroprotective effect of the calcium channel blocker nimodipine. However, it has not been proven which neuronal or glial cell types are affected by nimodipine and which mechanisms underlie these neuroprotective effects. Therefore, the aim of this study was to investigate the influence of nimodipine treatment on the in vitro neurotoxicity of different cell types in various stress models and to identify the associated molecular mechanisms. Therefore, cell lines from Schwann cells, neuronal cells and astrocytes were pretreated for 24 h with nimodipine and incubated under stress conditions such as osmotic, oxidative and heat stress. The cytotoxicity was measured via the lactate dehydrogenase (LDH) activity of cell culture supernatant. As a result, the nimodipine treatment led to a statistically significantly reduced cytotoxicity in Schwann cells and neurons during osmotic (p ≤ 0.01), oxidative (p ≤ 0.001) and heat stress (p ≤ 0.05), when compared to the vehicle. The cytotoxicity of astrocytes was nimodipine-dependently reduced during osmotic (p ≤ 0.01), oxidative (p ≤ 0.001) and heat stress (not significant). Moreover, a decreased caspase activity as well as an increased proteinkinase B (AKT) and cyclic adenosine monophosphate response element-binding protein (CREB) phosphorylation could be observed after the nimodipine treatment under different stress conditions. These results demonstrate a cell type-independent neuroprotective effect of the prophylactic nimodipine treatment, which is associated with the prevention of stress-dependent apoptosis through the activation of CREB and AKT signaling pathways and the reduction of caspase 3 activity.
Collapse
|
23
|
Walker CL, Wu X, Liu NK, Xu XM. Bisperoxovanadium Mediates Neuronal Protection through Inhibition of PTEN and Activation of PI3K/AKT-mTOR Signaling after Traumatic Spinal Injuries. J Neurotrauma 2019; 36:2676-2687. [PMID: 30672370 DOI: 10.1089/neu.2018.6294] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Although mechanisms involved in progression of cell death in spinal cord injury (SCI) have been studied extensively, few are clear targets for translation to clinical application. One of the best-understood mechanisms of cell survival in SCI is phosphatidylinositol-3-kinase (PI3K)/Akt and associated downstream signaling. Clear therapeutic efficacy of a phosphatase and tensin homologue (PTEN) inhibitor called bisperoxovanadium (bpV) has been shown in SCI, traumatic brain injury, stroke, and other neurological disease models in both neuroprotection and functional recovery. The present study aimed to elucidate mechanistic influences of bpV activity in neuronal survival in in vitro and in vivo models of SCI. Treatment with 100 nM bpV(pic) reduced cell death in a primary spinal neuron injury model (p < 0.05) in vitro, and upregulated both Akt and ribosomal protein S6 (pS6) activity (p < 0.05) compared with non-treated injured neurons. Pre-treatment of spinal neurons with a PI3K inhibitor, LY294002 or mammalian target of rapamycin (mTOR) inhibitor, rapamycin blocked bpV activation of Akt and ribosomal protein S6 activity, respectively. Treatment with bpV increased extracellular signal-related kinase (Erk) activity after scratch injury in vitro, and rapamycin reduced influence by bpV on Erk phosphorylation. After a cervical hemicontusive SCI, Akt phosphorylation decreased in total tissue via Western blot analysis (p < 0.01) as well as in penumbral ventral horn motor neurons throughout the first week post-injury (p < 0.05). Conversely, PTEN activity appeared to increase over this period. As observed in vitro, bpV also increased Erk activity post-SCI (p < 0.05). Our results suggest that PI3K/Akt signaling is the likely primary mechanism of bpV action in mediating neuroprotection in injured spinal neurons.
Collapse
Affiliation(s)
- Chandler L Walker
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, Indianapolis, Indiana.,Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Xiangbing Wu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Nai-Kui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, Indiana
| |
Collapse
|
24
|
Tang YJ, Li K, Yang CL, Huang K, Zhou J, Shi Y, Xie KG, Liu J. Bisperoxovanadium protects against spinal cord injury by regulating autophagy via activation of ERK1/2 signaling. DRUG DESIGN DEVELOPMENT AND THERAPY 2019; 13:513-521. [PMID: 30774313 PMCID: PMC6362923 DOI: 10.2147/dddt.s187878] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Background Spinal cord injury (SCI) is a disease of the central nervous system with few restorative treatments. Autophagy has been regarded as a promising therapeutic target for SCI. The inhibitor of phosphatase and tensin homolog deleted on chromosome ten (PTEN) bisperoxovanadium (bpV[pic]) had been claimed to provide a neuroprotective effect on SCI; but the underlying mechanism is still not fully understood. Materials and methods Acute SCI model were generated with SD Rats and were treated with control, acellular spinal cord scaffolds (ASC) obtained from normal rats, bpV(pic), and combined material of ASC and bpV(pic). We used BBB score to assess the motor function of the rats and the motor neurons were stained with Nissl staining. The expressions of the main autophagy markers LC3B, Beclin1 and P62, expressions of apoptosis makers Bax, Bcl2, PARP and Caspase 3 were detected with IF or Western Blot analysis. Results The bpV(pic) showed significant improvement in functional recovery by activating autophagy and accompanied by decreased neuronal apoptosis; combined ASC with bpV(pic) enhanced these effects. In addition, after treatment with ERK1/2 inhibitor SCH772984, we revealed that bpV(pic) promotes autophagy and inhibits apoptosis through activating ERK1/2 signaling after SCI. Conclusion These results illustrated that the bpV(pic) protects against SCI by regulating autophagy via activation of ERK1/2 signaling.
Collapse
Affiliation(s)
- Yu-Jin Tang
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Kai Li
- Academy of Orthopedics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China
| | - Cheng-Liang Yang
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Ke Huang
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Jing Zhou
- Department of Anatomy, Youjiang Medical University for Nationalities, Baise, Guangxi, China
| | - Yu Shi
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Ke-Gong Xie
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Jia Liu
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| |
Collapse
|
25
|
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.
Collapse
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
| |
Collapse
|
26
|
Zareen N, Dodson S, Armada K, Awad R, Sultana N, Hara E, Alexander H, Martin JH. Stimulation-dependent remodeling of the corticospinal tract requires reactivation of growth-promoting developmental signaling pathways. Exp Neurol 2018; 307:133-144. [PMID: 29729248 DOI: 10.1016/j.expneurol.2018.05.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/18/2018] [Accepted: 05/01/2018] [Indexed: 12/13/2022]
Abstract
The corticospinal tract (CST) can become damaged after spinal cord injury or stroke, resulting in weakness or paralysis. Repair of the damaged CST is limited because mature CST axons fail to regenerate, which is partly because the intrinsic axon growth capacity is downregulated in maturity. Whereas CST axons sprout after injury, this is insufficient to recover lost functions. Chronic motor cortex (MCX) electrical stimulation is a neuromodulatory strategy to promote CST axon sprouting, leading to functional recovery after CST lesion. Here we examine the molecular mechanisms of stimulation-dependent CST axonal sprouting and synapse formation. MCX stimulation rapidly upregulates mTOR and Jak/Stat signaling in the corticospinal system. Chronic stimulation, which leads to CST sprouting and increased CST presynaptic sites, further enhances mTOR and Jak/Stat activity. Importantly, chronic stimulation shifts the equilibrium of the mTOR repressor PTEN to the inactive phosphorylated form suggesting a molecular transition to an axon growth state. We blocked each signaling pathway selectively to determine potential differential contributions to axonal outgrowth and synapse formation. mTOR blockade prevented stimulation-dependent axon sprouting. Surprisingly, Jak/Stat blockade did not abrogate sprouting, but instead prevented the increase in CST presynaptic sites produced by chronic MCX stimulation. Chronic stimulation increased the number of spinal neurons expressing the neural activity marker cFos. Jak/Stat blockade prevented the increase in cFos-expressing neurons after chronic stimulation, confirming an important role for Jak/Stat signaling in activity-dependent CST synapse formation. MCX stimulation is a neuromodulatory repair strategy that reactivates distinct developmentally-regulated signaling pathways for axonal outgrowth and synapse formation.
Collapse
Affiliation(s)
- Neela Zareen
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Shahid Dodson
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Kristine Armada
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Rahma Awad
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Nadia Sultana
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Erina Hara
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Heather Alexander
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - John H Martin
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA; Neuroscience Program, Graduate Center of the City University of New York, New York, NY, USA.
| |
Collapse
|
27
|
Lentiviral vector delivery of short hairpin RNA to NgR1 promotes nerve regeneration and locomotor recovery in injured rat spinal cord. Sci Rep 2018; 8:5447. [PMID: 29615686 PMCID: PMC5882972 DOI: 10.1038/s41598-018-23751-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 03/15/2018] [Indexed: 01/01/2023] Open
Abstract
Nogo receptor 1 (NgR1) is a high-affinity receptor of myelin-associated inhibitors (MAIs), and suppresses neurogenesis. Lentiviral vector are commonly used to alter the expression of targeted genes. However, little is known about the potential function of lentiviral vector harboring NgR1 shRNA (LV-NgR1 shRNA) on neurogenesis in spinal cord injury (SCI). In this study, the rats were randomly divided into three groups: including the LN (LV-NgR1 shRNA injection), LC (LV-control shRNA injection) and Sham (laminectomy only). Eight weeks post-injection of LV, spinal cords were examined by histology for changes in cavity size and by immunohistochemistry for changes in expression of NgR1, cell apoptosis, astrocytes, neurons and myelination. Motor function was assessed using the Basso, Beattie and Bresnahan (BBB) locomotor scale. Animals that received LV-NgR1 shRNA remarkably improved the motor function. These animals also showed an increase in levels of nerve fibers, synapses and myelination, a decrease in levels of lesion cavity and cell apoptosis at 8 weeks post-treatment. These findings give evidence that NgR1 may be a promising target for SCI treatment.
Collapse
|
28
|
Glaser M, Palmhof M, Schulte D, Schmid H, Stute G, Dick HB, Joachim SC. [Marginal protection of retinal cells by bisperoxovanadium : Appropriate therapy in the model of retinal ischemia?]. Ophthalmologe 2018; 116:152-163. [PMID: 29404677 DOI: 10.1007/s00347-018-0651-y] [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] [Indexed: 11/26/2022]
Abstract
BACKGROUND Ischemic processes usually lead to the destruction of retinal cells and therefore play a key role in a multitude of eye diseases. OBJECTIVE The aim of this study was to investigate whether bisperoxovanadium has a potential neuroprotective effect in an ischemia/reperfusion animal model. MATERIAL AND METHODS Initially, ischemia was induced in one eye of an ischemia/reperfusion model and 3 days later, a 14-day medication-based treatment was initiated. Bisperoxovanadium was administered intraperitoneally every 3 days. Subsequently, the number of ganglion cells, the rate of apoptosis, amacrine cells, macroglia, microglia, and their activation state, as well as photoreceptors were determined by histological and immunohistochemical analyses. RESULTS In comparison to the control group, a significant retinal ganglion cell loss, a significant reduction of the inner layers as well as a decrease in photoreceptor and amacrine cell numbers could be determined in the ischemic eyes. In addition, there was an increase in the number of microglia in these animals. The rats treated with bisperoxovanadium did not exhibit a significant neuroprotective effect regarding the number of ganglion cells, the rate of apoptosis, macroglia, amacrine cells, or photoreceptors; however, a low structural degeneration of photoreceptors could be observed as an effect of the treatment. Additionally, fewer microglia and activated microglia were observed after bisperoxovanadium treatment. CONCLUSION Bisperoxovanadium seems to have only a marginal neuroprotective effect on ischemic retinae. It needs to be examined whether earlier therapy onset, higher dose or different route of administration would significantly improve the results or whether this therapeutic approach is unsuitable.
Collapse
Affiliation(s)
- M Glaser
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
| | - M Palmhof
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
| | - D Schulte
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
| | - H Schmid
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
| | - G Stute
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
| | - H B Dick
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
| | - S C Joachim
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland.
| |
Collapse
|
29
|
Pulido R. PTEN Inhibition in Human Disease Therapy. Molecules 2018; 23:molecules23020285. [PMID: 29385737 PMCID: PMC6017825 DOI: 10.3390/molecules23020285] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 01/26/2018] [Accepted: 01/28/2018] [Indexed: 12/19/2022] Open
Abstract
The tumor suppressor PTEN is a major homeostatic regulator, by virtue of its lipid phosphatase activity against phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3], which downregulates the PI3K/AKT/mTOR prosurvival signaling, as well as by its protein phosphatase activity towards specific protein targets. PTEN catalytic activity is crucial to control cell growth under physiologic and pathologic situations, and it impacts not only in preventing tumor cell survival and proliferation, but also in restraining several cellular regeneration processes, such as those associated with nerve injury recovery, cardiac ischemia, or wound healing. In these conditions, inhibition of PTEN catalysis is being explored as a potentially beneficial therapeutic intervention. Here, an overview of human diseases and conditions in which PTEN inhibition could be beneficial is presented, together with an update on the current status of specific small molecule inhibitors of PTEN enzymatic activity, their use in experimental models, and their limitations as research or therapeutic drugs.
Collapse
Affiliation(s)
- Rafael Pulido
- Biomarkers in Cancer Unit, Biocruces Health Research Institute, 48903 Barakaldo, Spain.
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain.
| |
Collapse
|
30
|
Walker CL, Zhang YP, Liu Y, Li Y, Walker MJ, Liu NK, Shields CB, Xu XM. Anatomical and functional effects of lateral cervical hemicontusion in adult rats. Restor Neurol Neurosci 2018; 34:389-400. [PMID: 27163248 DOI: 10.3233/rnn-150597] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE Cervical injuries are the most common form of spinal cord injury (SCI), and are often complicated by pathological secondary damage. Therefore, cervical SCI is of great clinical importance for understanding pathology and potential therapies. Here we utilize a weight drop cervical hemi-contusion injury model using a NYU/MASCIS impactor that produced graded anatomical and functional deficits. METHODS Three groups of rats were established: 1) Sham (laminectomy only) (n = 6), 12.5 mm weight drop (n = 10), and 25 mm weight drop (n = 10) SCI groups. Forelimb functional assessments of grooming ability, cereal manipulation, and forepaw adhesive removal were performed weekly after injury. Using transcranial magnetic motor evoked potentials (tcMMEPs), supraspinal motor stimulations were recorded in both forelimbs and hindlimbs at 5 and 28d post-injury. Lesion volume and myelinated tissue area were assessed through histological analysis. RESULTS A 12.5 mm weight drop height produced considerable tissue damage compared to Sham animals, while a 25 mm drop induced even greater damage than the 12.5 mm drop (p < 0.05). Forelimb functional assessments showed that increased injury severity and tissue damage was correlated to the degree of forelimb functional deficits. Interestingly, the hindlimbs showed little to no motor function loss. Upon tcMMEP stimulation, surprisingly little motor signal was recorded in the hindlimbs despite outward evidence of hindlimb motor recovery. CONCLUSIONS Our findings highlight a correlation between anatomical damage and functional outcome in a graded cervical hemi-contusion model, and support a loss of descending motor control from supraspinal inputs and intraspinal plasticity that promote spontaneous hindlimb functional recovery in this model.
Collapse
Affiliation(s)
- Chandler L Walker
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Yucheng Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yiping Li
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Melissa J Walker
- Medical Neuroscience Program, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Nai-Kui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, 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.,Medical Neuroscience Program, Indiana University School of Medicine, Indianapolis, IN, USA
| |
Collapse
|
31
|
McLoughlin NM, Mueller C, Grossmann TN. The Therapeutic Potential of PTEN Modulation: Targeting Strategies from Gene to Protein. Cell Chem Biol 2018; 25:19-29. [DOI: 10.1016/j.chembiol.2017.10.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/05/2017] [Accepted: 10/23/2017] [Indexed: 01/04/2023]
|
32
|
"mTOR Signaling Pathway": A Potential Target of Curcumin in the Treatment of Spinal Cord Injury. BIOMED RESEARCH INTERNATIONAL 2017; 2017:1634801. [PMID: 28691015 PMCID: PMC5485291 DOI: 10.1155/2017/1634801] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 04/15/2017] [Accepted: 05/18/2017] [Indexed: 01/09/2023]
Abstract
The purpose of this review is to discuss the possibility of the treatment of spinal cord injury (SCI) with curcumin via regulating the mTOR signaling pathway, which may provide another strong support for curcumin to be a promising medicine applied to the treatment of SCI. Curcumin is termed as a multifunctional targeting therapy drug that regulates the mTOR signaling pathway in the treatment of numerous diseases. Previous research has already revealed that mTOR signaling pathway plays a vital role in prognosis, which involves the axon regeneration and autophagy. This review discusses a potential mechanism that curcumin suppresses the activation of this pathway and ameliorates the microenvironment of axons regeneration which would provide a new way that induces autophagy appropriately.
Collapse
|
33
|
Transcriptional and Epigenetic Regulation in Injury-Mediated Neuronal Dendritic Plasticity. Neurosci Bull 2016; 33:85-94. [PMID: 27730386 DOI: 10.1007/s12264-016-0071-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 08/27/2016] [Indexed: 12/26/2022] Open
Abstract
Injury to the nervous system induces localized damage in neural structures and neuronal death through the primary insult, as well as delayed atrophy and impaired plasticity of the delicate dendritic fields necessary for interneuronal communication. Excitotoxicity and other secondary biochemical events contribute to morphological changes in neurons following injury. Evidence suggests that various transcription factors are involved in the dendritic response to injury and potential therapies. Transcription factors play critical roles in the intracellular regulation of neuronal morphological plasticity and dendritic growth and patterning. Mounting evidence supports a crucial role for epigenetic modifications via histone deacetylases, histone acetyltransferases, and DNA methyltransferases that modify gene expression in neuronal injury and repair processes. Gene regulation through epigenetic modification is of great interest in neurotrauma research, and an early picture is beginning to emerge concerning how injury triggers intracellular events that modulate such responses. This review provides an overview of injury-mediated influences on transcriptional regulation through epigenetic modification, the intracellular processes involved in the morphological consequences of such changes, and potential approaches to the therapeutic manipulation of neuronal epigenetics for regulating gene expression to facilitate growth and signaling through dendritic arborization following injury.
Collapse
|
34
|
Matsuda S, Ichimura M, Ogino M, Nakano N, Minami A, Murai T, Kitagishi Y. Effective PI3K modulators for improved therapy against malignant tumors and for neuroprotection of brain damage after tumor therapy (Review). Int J Oncol 2016; 49:1785-1790. [PMID: 27826621 DOI: 10.3892/ijo.2016.3710] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 09/15/2016] [Indexed: 11/06/2022] Open
Abstract
Due to the key role in various cellular processes including cell proliferation and cell survival on many cell types, dysregulation of the PI3K/AKT pathway represents a crucial step of the pathogenesis in many diseases. Furthermore, the tumor suppressor PTEN negatively regulates the PI3K/AKT pathway through its lipid phosphatase activity, which is recognized as one of the most frequently deleted and/or mutated genes in human cancer. Given the pervasive involvement of this pathway, the development of the molecules that modulate this PI3K/AKT signaling has been initiated in studies which focus on the extensive effective drug discovery. Consequently, the PI3K/AKT pathway appears to be an attractive pharmacological target both for cancer therapy and for neurological protection necessary after the therapy. A better understanding of the molecular relations could reveal new targets for treatment development. We review recent studies on the features of PI3K/AKT and PTEN, and their pleiotropic functions relevant to the signaling pathways involved in cancer progress and in neuronal damage by the therapy.
Collapse
Affiliation(s)
- Satoru Matsuda
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Mayuko Ichimura
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Mako Ogino
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Noriko Nakano
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Akari Minami
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Toshiyuki Murai
- Department of Microbiology and Immunology and Department of Genome Biology, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yasuko Kitagishi
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| |
Collapse
|
35
|
Chen J, Zhuang Y, Zhang ZF, Wang S, Jin P, He C, Hu PC, Wang ZF, Li ZQ, Xia GM, Li G, Wang Y, Wan Q. Glycine confers neuroprotection through microRNA-301a/PTEN signaling. Mol Brain 2016; 9:59. [PMID: 27230112 PMCID: PMC4880874 DOI: 10.1186/s13041-016-0241-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 05/17/2016] [Indexed: 12/22/2022] Open
Abstract
Background Glycine is known to protect against neuronal death. However, the underlying mechanism remains to be elucidated. The microRNA-301a is involved in both biological and pathological processes. But it is not known whether microRNA-301a has a neuroprotective property. In this study, we aimed to determine whether glycine-induced neuroprotection requires microRNA-301a-dependent signaling. Results We provided the first evidence that glycine increased the expression of microRNA-301a in cultured rat cortical neurons and protected against cortical neuronal death through up-regulation of microRNA-301a after oxygen-glucose deprivation. MicroRNA-301a directly bound the predicted 3′UTR target sites of PTEN and reduced PTEN expression in cortical neurons. We revealed that PTEN down-regulation by microRNA-301a mediated glycine-induced neuroprotective effect following oxygen-glucose deprivation. Conclusions Our results suggest that 1) microRNA-301a is neuroprotective in oxygen-glucose deprivation-induced neuronal injury; 2) glycine is an upstream regulator of microRNA-301a; 3) glycine confers neuroprotection through microRNA-301a/PTEN signal pathway.
Collapse
Affiliation(s)
- Juan Chen
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China.,Department of Neurology, the Central Hospital of Wuhan, Wuhan, 430060, China
| | - Yang Zhuang
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Zhi-Feng Zhang
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Shu Wang
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Ping Jin
- Department of Neurology, the Central Hospital of Wuhan, Wuhan, 430060, China
| | - Chunjiang He
- Department of Genetics, School of Basic Medical Sciences, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Peng-Chao Hu
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Ze-Fen Wang
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Zhi-Qiang Li
- Department of Neurosurgery, Zhongnan Hospital, Wuhan University School of Medicine, 169 Donghu Street, Wuhan, 430071, China
| | - Guang-Ming Xia
- Department of Neurology, the Central Hospital of Huanggang, Huanggang, 438000, China
| | - Gang Li
- Department of Neurology, the Central Hospital of Huanggang, Huanggang, 438000, China
| | - Yuan Wang
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China
| | - Qi Wan
- Department of Physiology, School of Basic Medical Sciences, Medical Research Institute, Wuhan University School of Medicine, 185 Donghu Street, Wuhan, 430071, China. .,Department of Neurosurgery, Zhongnan Hospital, Wuhan University School of Medicine, 169 Donghu Street, Wuhan, 430071, China.
| |
Collapse
|
36
|
Chen CH, Sung CS, Huang SY, Feng CW, Hung HC, Yang SN, Chen NF, Tai MH, Wen ZH, Chen WF. The role of the PI3K/Akt/mTOR pathway in glial scar formation following spinal cord injury. Exp Neurol 2016; 278:27-41. [PMID: 26828688 DOI: 10.1016/j.expneurol.2016.01.023] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 01/19/2016] [Accepted: 01/28/2016] [Indexed: 12/18/2022]
Abstract
Several studies suggest that glial scars pose as physical and chemical barriers that limit neurite regeneration after spinal cord injury (SCI). Evidences suggest that the activation of the PI3K/Akt/mTOR signaling pathway is involved in glial scar formation. Therefore, inhibition of the PI3K/Akt/mTOR pathway may beneficially attenuate glial scar formation after SCI. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) negatively regulates the PI3K/Akt/mTOR pathway. Therefore, we hypothesized that the overexpression of PTEN in the spinal cord will have beneficial effects after SCI. In the present study, we intrathecally injected a recombinant adenovirus carrying the pten gene (Ad-PTEN) to cause overexpression of PTEN in rats with contusion injured spinal cords. The results suggest overexpression of PTEN in spinal cord attenuated glial scar formation and led to improved locomotor function after SCI. Overexpression of PTEN following SCI attenuated gliosis, affected chondroitin sulfate proteoglycan expression, and improved axon regeneration into the lesion site. Furthermore, we suggest that the activation of the PI3K/Akt/mTOR pathway in astrocytes at 3 days after SCI may be involved in glial scar formation. Because delayed treatment with Ad-PTEN enhanced motor function recovery more significantly than immediate treatment with Ad-PTEN after SCI, the results suggest that the best strategy to attenuate glial scar formation could be to introduce 3 days after SCI. This study's findings thus have positive implications for patients who are unable to receive immediate medical attention after SCI.
Collapse
Affiliation(s)
- Chun-Hong Chen
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung, Taiwan
| | - Chun-Sung Sung
- Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Shi-Ying Huang
- Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Chien-Wei Feng
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung, Taiwan
| | - Han-Chun Hung
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung, Taiwan
| | - San-Nan Yang
- I-Shou University, School of Medicine, College of Medicine and Department of Pediatrics, E-DA Hospital, Kaohsiung, Taiwan
| | - Nan-Fu Chen
- Division of Neurosurgery, Department of Surgery, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan
| | - Ming-Hong Tai
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung, Taiwan; Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan; Center for Neuroscience, National Sun Yat-sen University, Kaohsiung, Taiwan; Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Zhi-Hong Wen
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung, Taiwan; Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan.
| | - Wu-Fu Chen
- Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan; Department of Neurosurgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
| |
Collapse
|
37
|
Morris R, Whishaw IQ. A Proposal for a Rat Model of Spinal Cord Injury Featuring the Rubrospinal Tract and its Contributions to Locomotion and Skilled Hand Movement. Front Neurosci 2016; 10:5. [PMID: 26858587 PMCID: PMC4728831 DOI: 10.3389/fnins.2016.00005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 01/07/2016] [Indexed: 11/21/2022] Open
Abstract
Spinal cord injury and repair is a dynamic field of research. The development of reliable animal models of traumatic spinal cord injury has been invaluable in providing a wealth of information regarding the pathological consequences and recovery potential of this condition. A number of injury models have been instrumental in the elaboration and the validation of therapeutic interventions aimed at reversing this once thought permanent condition. In general, the study of spinal cord injury and repair is made difficult by both its anatomical complexity and the complexity of the behavior it mediates. In this perspective paper, we suggest a new model for spinal cord investigation that simplifies problems related to both the functional and anatomical complexity of the spinal cord. We begin by reviewing and contrasting some of the most common animal models used for investigating spinal cord dysfunction. We then consider two widely used models of spinal deficit-recovery, one involving the corticospinal tracts (CTS) and the other the rubrospinal tract (RST). We argue that the simplicity of the function of the RST makes it a useful model for studying the cord and its functional repair. We also reflect on two obstacles that have hindered progress in the pre-clinical field, delaying translation to the clinical setup. The first is recovery of function without reconnection of the transected descending fibers and the second is the use of behavioral paradigms that are not under the control of the descending fiber pathway under scrutiny.
Collapse
Affiliation(s)
- Renée Morris
- Translational Neuroscience Facility, School of Medical Sciences, The University of New South Wales Australia Sydney, NSW, Australia
| | - Ian Q Whishaw
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge Lethbridge, AB, Canada
| |
Collapse
|
38
|
Ewan EE, Hagg T. Intrathecal Acetyl-L-Carnitine Protects Tissue and Improves Function after a Mild Contusive Spinal Cord Injury in Rats. J Neurotrauma 2015; 33:269-77. [PMID: 26415041 DOI: 10.1089/neu.2015.4030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Primary and secondary ischemia after spinal cord injury (SCI) contributes to tissue and axon degeneration, which may result from decreased energy substrate availability for cellular and axonal mitochondrial adenosine triphosphate (ATP) production. Therefore, providing spinal tissue with an alternative energy substrate during ischemia may be neuroprotective after SCI. To assess this, rats received a mild contusive SCI (120 kdyn, Infinite Horizons impactor) at thoracic level 9 (T9), which causes loss of ∼ 80% of the ascending sensory dorsal column axonal projections to the gracile nucleus. Immediately afterwards, the energy substrate acetyl-L-carnitine (ALC; 1 mg/day) or phosphate-buffered saline (PBS) was infused intrathecally (sub-arachnoid) for 6 days via an L5/6 catheter attached to a subcutaneous Alzet pump. ALC treatment improved overground locomotor function (Basso-Beattie-Breshnahan [BBB] score 18 vs. 13) at 6 days, total spared epicenter (71% vs. 57%) and penumbra white matter (90% vs. 85%), ventral penumbra microvessels (108% vs. 79%), and penumbra motor neurons (42% vs. 15%) at 15 days post-SCI, compared with PBS treatment. However, the ascending sensory projections (anterogradely traced with cholera toxin B from the sciatic nerves) and dorsal column white matter and perfused blood vessels were not protected. Furthermore, grid walking, a task we have shown to be dependent on dorsal column function, was not improved. Thus, mitochondrial substrate replacement may only be efficacious in areas of lesser or temporary ischemia, such as the ventral spinal cord and injury penumbra in this study. The current data also support our previous evidence that microvessel loss is central to secondary tissue degeneration.
Collapse
Affiliation(s)
- Eric E Ewan
- Kentucky Spinal Cord Injury Research Center and Department of Neurological Surgery, University of Louisville , Louisville, Kentucky
| | - Theo Hagg
- Kentucky Spinal Cord Injury Research Center and Department of Neurological Surgery, University of Louisville , Louisville, Kentucky
| |
Collapse
|
39
|
Abstract
The intrinsic growth ability of all the neurons declines during development although some may grow better than others. Numerous intracellular signaling proteins and transcription factors have been shown to regulate the intrinsic growth capacity in mature neurons. Among them, PI3 kinase/Akt pathway is important for controlling axon elongation. As a negative regulator of this pathway, the tumor suppressor phosphatase and tensin homolog (PTEN) appears critical to control the regenerative ability of young and adult neurons. This review will focus on recent research progress in axon regeneration and neural repair by PTEN inhibition and therapeutic potential of blocking this phosphatase for neurological disorders. Inhibition of PTEN by deletion in conditional knockout mice, knockdown by short-hairpin RNA, or blockade by pharmacological approaches, including administration of selective PTEN antagonist peptides, stimulates various degrees of axon regrowth in juvenile or adult rodents with central nervous system injuries. Importantly, post-injury PTEN suppression could enhance axonal growth and functional recovery in adult central nervous system after injury.
Collapse
Affiliation(s)
- Yosuke Ohtake
- Shriners Hospitals Pediatric Research Center, Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA, USA
| | - Umar Hayat
- Shriners Hospitals Pediatric Research Center, Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA, USA
| | - Shuxin Li
- Shriners Hospitals Pediatric Research Center, Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA, USA
| |
Collapse
|
40
|
Guan Y, Yang F, Yao Q, Shi J, Wang G, Gu Z, Zhou F, Shen J. Impacts of phosphatase and tensin homology deleted on chromosome ten (PTEN)-inhibiting chitosan scaffold on growth and differentiation of neural stem cells. Int J Clin Exp Med 2015; 8:14308-14315. [PMID: 26550415 PMCID: PMC4613100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 08/06/2015] [Indexed: 06/05/2023]
Abstract
OBJECTIVE The aim of this study was to investigate growth and differentiation of neural stem cells (NSCs) on the phosphatase and tensin homology deleted on chromosome ten (PTEN)-inhibitor-adsorbed chitosan scaffold. METHODS NSCs were divide into the chitosan group and the control groups, and performed CCK-8 test on 1(st), 3(rd) and 7(th) d to compare the proliferation between the 2 groups. The chitosan scaffold adsorbed PTEN inhibitor bpv (pic), and the empty scaffold was used as the control for co-culture of NSCs, immunofluorescence staining was performed on 7(th) d to detect the differentiation of NSCs on the scaffold. RESULTS The results of CCK-8 test showed no significant difference in the absorbance between the 2 groups. Immunofluorescence staining showed that the NSCs numbers of the bpv scaffold group were more than the empty scaffold group, among which the anti-glial fibrillary acidic protein (GFAP) positive cells were less than the empty scaffold group, while the anti-β-Tubulin III positive cells were more than the empty scaffold group, the two groups both showed rare anti-receptor-interacting protein (RIP) positive cells. CONCLUSIONS Chitosan scaffold exhibited good compatibility to NSCs, the PTEN-inhibitor-adsorbed chitosan scaffold could promote the migration of NSCs towards the scaffold and their differentiation towards neurons.
Collapse
Affiliation(s)
- Yixiang Guan
- Department of Neurosurgery, Affiliated Haian Hospital of Nantong UniversityNantong 226001, China
| | - Fu Yang
- Department of Neurosurgery, Affiliated Hospital of Nantong UniversityNantong 226001, China
| | - Qi Yao
- Department of Neurosurgery, Affiliated Hospital of Nantong UniversityNantong 226001, China
| | - Jinlong Shi
- Department of Neurosurgery, Affiliated Hospital of Nantong UniversityNantong 226001, China
| | - Gequan Wang
- Department of Neurosurgery, Yili Xinhua HospitalYining 835000, China
| | - Zhikai Gu
- Department of Neurosurgery, Affiliated Hospital of Nantong UniversityNantong 226001, China
| | - Fei Zhou
- Department of Neurosurgery, Affiliated Hospital of Nantong UniversityNantong 226001, China
| | - Jianhong Shen
- Department of Neurosurgery, Affiliated Hospital of Nantong UniversityNantong 226001, China
| |
Collapse
|
41
|
Wang Y, Schachner M. The intracellular domain of L1CAM binds to casein kinase 2α and is neuroprotective via inhibition of the tumor suppressors PTEN and p53. J Neurochem 2015; 133:828-43. [PMID: 25727698 DOI: 10.1111/jnc.13083] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/05/2015] [Accepted: 02/24/2015] [Indexed: 02/05/2023]
Abstract
Cell adhesion molecule L1 promotes neuritogenesis and neuronal survival through triggering MAPK pathways. Based on the findings that L1 is associated with casein kinase 2 (CK2), and that deficiency in PTEN promotes neuritogenesis in vitro and regeneration after trauma, we examined the functional relationship between L1 and PTEN. In parallel, we investigated the tumor suppressor p53, which also regulates neuritogenesis. Here, we report that the intracellular domain of L1 binds to the subunit CK2α, and that knockdown of L1 leads to CK2 dephosphorylation and an increase in PTEN and p53 levels. Overexpression of L1, but not the L1 mutants L1 (S1181N, E1184V), which reduced binding between L1 and CK2, reduced expression levels of PTEN and p53 proteins, and enhanced levels of phosphorylated CK2α and mammalian target of rapamycin, which is a downstream effector of PTEN and p53. Treatment of neurons with a CK2 inhibitor or transfection with CK2α siRNA increased levels of PTEN and p53, and inhibited neuritogenesis. The combined observations indicate that L1 downregulates expression of PTEN and p53 via direct binding to CK2α. We suggest that L1 stimulates neuritogenesis by activating CK2α leading to decreased levels of PTEN and p53 via a novel, L1-triggered and CK2α-mediated signal transduction pathway. L1CAM (L1 cell adhesion molecule) is implicated in neural functions through the cognate src/MAP kinase signaling pathway. We now describe a novel signaling platform operating via the alpha subunit of casein kinase 2 which binds to the intracellular domain of L1. Knockdown of L1CAM leads to increased levels of tumor suppressor PTEN (phosphatase and tensin homolog) and p53, known to inhibit neuritogenesis in vitro and recovery from trauma in vivo. By activating this enzyme, L1CAM adds to its beneficial functions by decreasing the levels of PTEN and p53.
Collapse
Affiliation(s)
- Yan Wang
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong, China
| | - Melitta Schachner
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong, China
| |
Collapse
|
42
|
Targeting PTEN using small molecule inhibitors. Methods 2015; 77-78:63-8. [DOI: 10.1016/j.ymeth.2015.02.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 02/15/2015] [Accepted: 02/16/2015] [Indexed: 12/22/2022] Open
|
43
|
Waugh MG. PIPs in neurological diseases. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1066-82. [PMID: 25680866 DOI: 10.1016/j.bbalip.2015.02.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/29/2015] [Accepted: 02/01/2015] [Indexed: 12/19/2022]
Abstract
Phosphoinositide (PIP) lipids regulate many aspects of cell function in the nervous system including receptor signalling, secretion, endocytosis, migration and survival. Levels of PIPs such as PI4P, PI(4,5)P2 and PI(3,4,5)P3 are normally tightly regulated by phosphoinositide kinases and phosphatases. Deregulation of these biochemical pathways leads to lipid imbalances, usually on intracellular endosomal membranes, and these changes have been linked to a number of major neurological diseases including Alzheimer's, Parkinson's, epilepsy, stroke, cancer and a range of rarer inherited disorders including brain overgrowth syndromes, Charcot-Marie-Tooth neuropathies and neurodevelopmental conditions such as Lowe's syndrome. This article analyses recent progress in this area and explains how PIP lipids are involved, to varying degrees, in almost every class of neurological disease. This article is part of a Special Issue entitled Brain Lipids.
Collapse
Affiliation(s)
- Mark G Waugh
- Lipid and Membrane Biology Group, Institute for Liver and Digestive Health, UCL, Royal Free Campus, Rowland Hill Street, London NW3 2PF, United Kingdom.
| |
Collapse
|
44
|
Walker CL, Wang X, Bullis C, Liu NK, Lu Q, Fry C, Deng L, Xu XM. Biphasic bisperoxovanadium administration and Schwann cell transplantation for repair after cervical contusive spinal cord injury. Exp Neurol 2014; 264:163-72. [PMID: 25510318 DOI: 10.1016/j.expneurol.2014.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Revised: 11/30/2014] [Accepted: 12/03/2014] [Indexed: 11/20/2022]
Abstract
Schwann cells (SCs) hold promise for spinal cord injury (SCI) repair; however, there are limitations for its use as a lone treatment. We showed that acute inhibition of the phosphatase and tensin homolog deleted on chromosome ten (PTEN) by bisperoxovanadium (bpV) was neuroprotective and enhanced function following cervical hemicontusion SCI. We hypothesized that combining acute bpV therapy and delayed SC engraftment would further improve neuroprotection and recovery after cervical SCI. Adult female Sprague-Dawley (SD) rats were randomly sorted into 5 groups: sham, vehicle, bpV, SC transplantation, and bpV+SC transplantation. SCs were isolated from adult green fluorescent protein (GFP)-expressing SD rats (GFP-SCs). 200 μg/kg bpV(pic) was administered intraperitoneally (IP) twice daily for 7 days post-SCI in bpV-treated groups. GFP-SCs (1×10(6) in 5 μl medium) were transplanted into the lesion epicenter at the 8th day post-SCI. Forelimb function was tested for 10 weeks and histology was assessed. bpV alone significantly reduced lesion (by 40%, p<0.05) and cavitation (by 65%, p<0.05) and improved functional recovery (p<0.05) compared to injury alone. The combination promoted similar neuroprotection (p<0.01 vs. injury); however, GFP-SCs alone did not. Both SC-transplanted groups exhibited remarkable long-term SC survival, SMI-31(+) axon ingrowth and RECA-1(+) vasculature presence in the SC graft; however, bpV+SCs promoted an 89% greater axon-to-lesion ratio than SCs only. We concluded that bpV likely contributed largely to the neuroprotective and functional benefits while SCs facilitated considerable host-tissue interaction and modification. The combination of the two shows promise as an attractive strategy to enhance recovery after SCI.
Collapse
Affiliation(s)
- Chandler L Walker
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Xiaofei Wang
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Carli Bullis
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Nai-Kui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Qingbo Lu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Colin Fry
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Lingxiao Deng
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| |
Collapse
|