1
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Schartz ND, Liang HY, Carvalho K, Chu SH, Mendoza-Arvilla A, Petrisko TJ, Gomez-Arboledas A, Mortazavi A, Tenner AJ. C5aR1 antagonism suppresses inflammatory glial responses and alters cellular signaling in an Alzheimer's disease mouse model. Nat Commun 2024; 15:7028. [PMID: 39147742 PMCID: PMC11327341 DOI: 10.1038/s41467-024-51163-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 07/30/2024] [Indexed: 08/17/2024] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia in older adults, and the need for effective, sustainable therapeutic targets is imperative. The complement pathway has been proposed as a therapeutic target. C5aR1 inhibition reduces plaque load, gliosis, and memory deficits in animal models, however, the cellular bases underlying this neuroprotection were unclear. Here, we show that the C5aR1 antagonist PMX205 improves outcomes in the Arctic48 mouse model of AD. A combination of single cell and single nucleus RNA-seq analysis of hippocampi derived from males and females identified neurotoxic disease-associated microglia clusters in Arctic mice that are C5aR1-dependent, while microglial genes associated with synapse organization and transmission and learning were overrepresented in PMX205-treated mice. PMX205 also reduced neurotoxic astrocyte gene expression, but clusters associated with protective responses to injury were unchanged. C5aR1 inhibition promoted mRNA-predicted signaling pathways between brain cell types associated with cell growth and repair, while suppressing inflammatory pathways. Finally, although hippocampal plaque load was unaffected, PMX205 prevented deficits in short-term memory in female Arctic mice. In conclusion, C5aR1 inhibition prevents cognitive loss, limits detrimental glial polarization while permitting neuroprotective responses, as well as leaving most protective functions of complement intact, making C5aR1 antagonism an attractive therapeutic strategy for AD.
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Affiliation(s)
- Nicole D Schartz
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Heidi Y Liang
- Department of Developmental & Cell Biology, University of California, Irvine, Irvine, CA, USA
| | - Klebea Carvalho
- Department of Developmental & Cell Biology, University of California, Irvine, Irvine, CA, USA
| | - Shu-Hui Chu
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Adrian Mendoza-Arvilla
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Tiffany J Petrisko
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Angela Gomez-Arboledas
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Ali Mortazavi
- Department of Developmental & Cell Biology, University of California, Irvine, Irvine, CA, USA
| | - Andrea J Tenner
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA.
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA.
- Department of Pathology and Laboratory Medicine, University of California, Irvine, School of Medicine, Irvine, CA, USA.
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2
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González-Orozco JC, Escobedo-Avila I, Velasco I. Transcriptome Profiling after Early Spinal Cord Injury in the Axolotl and Its Comparison with Rodent Animal Models through RNA-Seq Data Analysis. Genes (Basel) 2023; 14:2189. [PMID: 38137011 PMCID: PMC10742908 DOI: 10.3390/genes14122189] [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: 10/17/2023] [Revised: 11/20/2023] [Accepted: 11/27/2023] [Indexed: 12/24/2023] Open
Abstract
BACKGROUND Traumatic spinal cord injury (SCI) is a disabling condition that affects millions of people around the world. Currently, no clinical treatment can restore spinal cord function. Comparison of molecular responses in regenerating to non-regenerating vertebrates can shed light on neural restoration. The axolotl (Ambystoma mexicanum) is an amphibian that regenerates regions of the brain or spinal cord after damage. METHODS In this study, we compared the transcriptomes after SCI at acute (1-2 days after SCI) and sub-acute (6-7 days post-SCI) periods through the analysis of RNA-seq public datasets from axolotl and non-regenerating rodents. RESULTS Genes related to wound healing and immune responses were upregulated in axolotls, rats, and mice after SCI; however, the immune-related processes were more prevalent in rodents. In the acute phase of SCI in the axolotl, the molecular pathways and genes associated with early development were upregulated, while processes related to neuronal function were downregulated. Importantly, the downregulation of processes related to sensorial and motor functions was observed only in rodents. This analysis also revealed that genes related to pluripotency, cytoskeleton rearrangement, and transposable elements (e.g., Sox2, Krt5, and LOC100130764) were among the most upregulated in the axolotl. Finally, gene regulatory networks in axolotls revealed the early activation of genes related to neurogenesis, including Atf3/4 and Foxa2. CONCLUSIONS Immune-related processes are upregulated shortly after SCI in axolotls and rodents; however, a strong immune response is more noticeable in rodents. Genes related to early development and neurogenesis are upregulated beginning in the acute stage of SCI in axolotls, while the loss of motor and sensory functions is detected only in rodents during the sub-acute period of SCI. The approach employed in this study might be useful for designing and establishing regenerative therapies after SCI in mammals, including humans.
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Affiliation(s)
- Juan Carlos González-Orozco
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico; (J.C.G.-O.); (I.E.-A.)
| | - Itzel Escobedo-Avila
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico; (J.C.G.-O.); (I.E.-A.)
| | - Iván Velasco
- Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico; (J.C.G.-O.); (I.E.-A.)
- Laboratorio de Reprogramación Celular, Instituto Nacional de Neurología y Neurocirugía “Manuel Velasco Suárez”, Mexico City 14269, Mexico
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3
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Shen K, Li X, Huang G, Yuan Z, Xie B, Chen T, He L. High rapamycin-loaded hollow mesoporous Prussian blue nanozyme targets lesion area of spinal cord injury to recover locomotor function. Biomaterials 2023; 303:122358. [PMID: 37951099 DOI: 10.1016/j.biomaterials.2023.122358] [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: 04/11/2023] [Revised: 09/09/2023] [Accepted: 10/17/2023] [Indexed: 11/13/2023]
Abstract
Scavenging free radicals and reducing inflammatory reaction to relieve the secondary damage are important issues in the spinal cord injury (SCI) therapeutic strategy. Nanozymes attract more attention in the drug development of SCI due to the high stability, long-lasting catalytic capacity, and multienzyme-like properties. Herein, we constructed a Rapamycin (Rapa)-loaded and hollow mesoporous Prussian blue (HMPB)-based nanozyme (RHPAzyme) to realize the combined antioxidation and anti-inflammation combination therapy of SCI. Furthermore, activated cell penetrating peptide (ACPP) is modified onto nanozyme to endow the effectively ability of lesion area-targeting. This RHPAzyme exhibits ROS scavenging capacity with the transformation of Fe2+/Fe3+ valance and cyanide group of HMPB to achieve multienzyme-like activity. As expected, RHPAzyme scavenges the ROS overproduction and reduces inflammation in oxygen-glucose deprivation (OGD)-induced damage via inhibiting MAPK/AKT signaling pathway. Furtherly, RHPAzyme exhibits the combined antioxidant and anti-inflammatory activity in vivo, which can effectively alleviate neuronal damage and promote motor function recovery in SCI mice. Overall, this study demonstrates the RHPAzyme induces an effective treatment of SCI by inhibiting oxygen-mediated cell apoptosis and suppressing inflammation-induced injury, thus reduces the nervous impairment and promotes motor function recovery.
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Affiliation(s)
- Kui Shen
- Department of Orthopedics, Department of Neurology and Stroke Center, The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Xiaowei Li
- Department of Orthopedics, Department of Neurology and Stroke Center, The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Guanning Huang
- Department of Orthopedics, Department of Neurology and Stroke Center, The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, 510632, China; Department of Chemistry, Jinan University, Guangzhou, 510632, China
| | - Zhongwen Yuan
- Department of Chemistry, Jinan University, Guangzhou, 510632, China
| | - Bin Xie
- Department of Chemistry, Jinan University, Guangzhou, 510632, China
| | - Tianfeng Chen
- Department of Orthopedics, Department of Neurology and Stroke Center, The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, 510632, China.
| | - Lizhen He
- Department of Orthopedics, Department of Neurology and Stroke Center, The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, 510632, China.
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4
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Schartz ND, Liang HY, Carvalho K, Chu SH, Mendoza-Arvilla A, Petrisko TJ, Gomez-Arboledas A, Mortazavi A, Tenner AJ. C5aR1 antagonism suppresses inflammatory glial gene expression and alters cellular signaling in an aggressive Alzheimer's model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.22.554306. [PMID: 37662399 PMCID: PMC10473603 DOI: 10.1101/2023.08.22.554306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Alzheimer's disease (AD) is the leading cause of dementia in older adults, and the need for effective, sustainable therapeutic targets is imperative. Pharmacologic inhibition of C5aR1 reduces plaque load, gliosis and memory deficits in animal models. However, the cellular basis underlying this neuroprotection and which processes were the consequence of amyloid reduction vs alteration of the response to amyloid were unclear. In the Arctic model, the C5aR1 antagonist PMX205 did not reduce plaque load, but deficits in short-term memory in female mice were prevented. Hippocampal single cell and single nucleus RNA-seq clusters revealed C5aR1 dependent and independent gene expression and cell-cell communication. Microglial clusters containing neurotoxic disease-associated microglial genes were robustly upregulated in Arctic mice and drastically reduced with PMX205 treatment, while genes in microglia clusters that were overrepresented in the Arctic-PMX205 vs Arctic group were associated with synapse organization and transmission and learning. PMX205 treatment also reduced some A-1 astrocyte genes. In spite of changes in transcript levels, overall protein levels of some reactive glial markers were relatively unchanged by C5aR1 antagonism, as were clusters associated with protective responses to injury. C5aR1 inhibition promoted signaling pathways associated with cell growth and repair, such as TGFβ and FGF, in Arctic mice, while suppressing inflammatory pathways including PROS, Pecam1, and EPHA. In conclusion, pharmacologic C5aR1 inhibition prevents cognitive loss, limits microglial polarization to a detrimental inflammatory state and permits neuroprotective responses, as well as leaving protective functions of complement intact, making C5aR1 antagonism an attractive therapeutic strategy for individuals with AD.
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Affiliation(s)
- Nicole D. Schartz
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA 92697
| | - Heidi Y. Liang
- Department of Developmental & Cell Biology, University of California, Irvine, Irvine, CA 92697
| | - Klebea Carvalho
- Department of Developmental & Cell Biology, University of California, Irvine, Irvine, CA 92697
| | - Shu-Hui Chu
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA 92697
| | - Adrian Mendoza-Arvilla
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA 92697
| | - Tiffany J. Petrisko
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA 92697
| | - Angela Gomez-Arboledas
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA 92697
| | - Ali Mortazavi
- Department of Developmental & Cell Biology, University of California, Irvine, Irvine, CA 92697
| | - Andrea J. Tenner
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA 92697
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697
- Department of Pathology and Laboratory Medicine, University of California, Irvine, School of Medicine, Irvine, CA 92697
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5
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Bringuier CM, Noristani HN, Perez JC, Cardoso M, Goze-Bac C, Gerber YN, Perrin FE. Up-Regulation of Astrocytic Fgfr4 Expression in Adult Mice after Spinal Cord Injury. Cells 2023; 12:cells12040528. [PMID: 36831195 PMCID: PMC9954417 DOI: 10.3390/cells12040528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/18/2023] [Accepted: 01/31/2023] [Indexed: 02/10/2023] Open
Abstract
Spinal cord injury (SCI) leads to persistent neurological deficits without available curative treatment. After SCI astrocytes within the lesion vicinity become reactive, these undergo major morphological, and molecular transformations. Previously, we reported that following SCI, over 10% of resident astrocytes surrounding the lesion spontaneously transdifferentiate towards a neuronal phenotype. Moreover, this conversion is associated with an increased expression of fibroblast growth factor receptor 4 (Fgfr4), a neural stem cell marker, in astrocytes. Here, we evaluate the therapeutic potential of gene therapy upon Fgfr4 over-expression in mature astrocytes following SCI in adult mice. We found that Fgfr4 over-expression in astrocytes immediately after SCI improves motor function recovery; however, it may display sexual dimorphism. Improved functional recovery is associated with a decrease in spinal cord lesion volume and reduced glial reactivity. Cell-specific transcriptomic profiling revealed concomitant downregulation of Notch signaling, and up-regulation of neurogenic pathways in converting astrocytes. Our findings suggest that gene therapy targeting Fgfr4 over-expression in astrocytes after injury is a feasible therapeutic approach to improve recovery following traumatism of the spinal cord. Moreover, we stress that a sex-dependent response to astrocytic modulation should be considered for the development of effective translational strategies in other neurological disorders.
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Affiliation(s)
| | | | | | - Maida Cardoso
- UMR 5221, Univ. Montpellier, CNRS, 34095 Montpellier, France
| | | | | | - Florence Evelyne Perrin
- MMDN, Univ. Montpellier, EPHE, INSERM, 34095 Montpellier, France
- Institut Universitaire de France (IUF), 75005 Paris, France
- Correspondence:
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6
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Boato F, Guan X, Zhu Y, Ryu Y, Voutounou M, Rynne C, Freschlin CR, Zumbo P, Betel D, Matho K, Makarov SN, Wu Z, Son YJ, Nummenmaa A, Huang JZ, Edwards DJ, Zhong J. Activation of MAP2K signaling by genetic engineering or HF-rTMS promotes corticospinal axon sprouting and functional regeneration. Sci Transl Med 2023; 15:eabq6885. [PMID: 36599003 DOI: 10.1126/scitranslmed.abq6885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Facilitating axon regeneration in the injured central nervous system remains a challenging task. RAF-MAP2K signaling plays a key role in axon elongation during nervous system development. Here, we show that conditional expression of a constitutively kinase-activated BRAF in mature corticospinal neurons elicited the expression of a set of transcription factors previously implicated in the regeneration of zebrafish retinal ganglion cell axons and promoted regeneration and sprouting of corticospinal tract (CST) axons after spinal cord injury in mice. Newly sprouting axon collaterals formed synaptic connections with spinal interneurons, resulting in improved recovery of motor function. Noninvasive suprathreshold high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) activated the BRAF canonical downstream effectors MAP2K1/2 and modulated the expression of a set of regeneration-related transcription factors in a pattern consistent with that induced by BRAF activation. HF-rTMS enabled CST axon regeneration and sprouting, which was abolished in MAP2K1/2 conditional null mice. These data collectively demonstrate a central role of MAP2K signaling in augmenting the growth capacity of mature corticospinal neurons and suggest that HF-rTMS might have potential for treating spinal cord injury by modulating MAP2K signaling.
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Affiliation(s)
- Francesco Boato
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Xiaofei Guan
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Yanjie Zhu
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Youngjae Ryu
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Mariel Voutounou
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Christopher Rynne
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Chase R Freschlin
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Paul Zumbo
- Applied Bioinformatics Core, Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
| | - Doron Betel
- Applied Bioinformatics Core, Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
| | - Katie Matho
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Sergey N Makarov
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.,Electrical and Computer Engineering Department, Worcester Polytechnic Institute, Worcester, MA 01609, USA
| | - Zhuhao Wu
- Icahn School of Medicine at Mount Sinai, New York, NY 10065, USA
| | - Young-Jin Son
- Shriners Hospitals Pediatric Research Center, Temple University, Philadelphia, PA 19140, USA
| | - Aapo Nummenmaa
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Josh Z Huang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.,Department of Neurobiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Dylan J Edwards
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Moss Rehabilitation Research Institute, Elkins Park, PA 19027, USA.,Thomas Jefferson University, Philadelphia, PA 19108, USA.,Exercise Medicine Research Institute, School of Biomedical and Health Sciences, Edith Cowan University, Joondalup 6027, Australia
| | - Jian Zhong
- Molecular Regeneration and Neuroimaging Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
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7
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Zochodne DW. Growth factors and molecular-driven plasticity in neurological systems. HANDBOOK OF CLINICAL NEUROLOGY 2023; 196:569-598. [PMID: 37620091 DOI: 10.1016/b978-0-323-98817-9.00017-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
It has been almost 70 years since the discovery of nerve growth factor (NGF), a period of a dramatic evolution in our understanding of dynamic growth, regeneration, and rewiring of the nervous system. In 1953, the extraordinary finding that a protein found in mouse submandibular glands generated a halo of outgrowing axons has now redefined our concept of the nervous system connectome. Central and peripheral neurons and their axons or dendrites are no longer considered fixed or static "wiring." Exploiting this molecular-driven plasticity as a therapeutic approach has arrived in the clinic with a slate of new trials and ideas. Neural growth factors (GFs), soluble proteins that alter the behavior of neurons, have expanded in numbers and our understanding of the complexity of their signaling and interactions with other proteins has intensified. However, beyond these "extrinsic" determinants of neuron growth and function are the downstream pathways that impact neurons, ripe for translational development and potentially more important than individual growth factors that may trigger them. Persistent and ongoing nuances in clinical trial design in some of the most intractable and irreversible neurological conditions give hope for connecting new biological ideas with clinical benefits. This review is a targeted update on neural GFs, their signals, and new therapeutic ideas, selected from an expansive literature.
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Affiliation(s)
- Douglas W Zochodne
- Division of Neurology, Department of Medicine and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.
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8
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Beine Z, Wang Z, Tsoulfas P, Blackmore MG. Single Nuclei Analyses Reveal Transcriptional Profiles and Marker Genes for Diverse Supraspinal Populations. J Neurosci 2022; 42:8780-8794. [PMID: 36202615 PMCID: PMC9698772 DOI: 10.1523/jneurosci.1197-22.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 09/07/2022] [Accepted: 09/29/2022] [Indexed: 01/18/2023] Open
Abstract
The mammalian brain contains numerous neurons distributed across forebrain, midbrain, and hindbrain that project axons to the lower spinal cord and work in concert to control movement and achieve homeostasis. Extensive work has mapped the anatomic location of supraspinal cell types and continues to establish specific physiological functions. The patterns of gene expression that typify and distinguish these disparate populations, however, are mostly unknown. Here, using adult mice of mixed sex, we combined retrograde labeling of supraspinal cell nuclei with fluorescence-activated nuclei sorting and single-nuclei RNA sequencing analyses to transcriptionally profile neurons that project axons from the brain to lumbar spinal cord. We identified 14 transcriptionally distinct cell types and used a combination of established and newly identified marker genes to assign an anatomic location to each. To validate the putative marker genes, we visualized selected transcripts and confirmed selective expression within lumbar-projecting neurons in discrete supraspinal regions. Finally, we illustrate the potential utility of these data by examining the expression of transcription factors that distinguish different supraspinal cell types and by surveying the expression of receptors for growth and guidance cues that may be present in the spinal cord. Collectively, these data establish transcriptional differences between anatomically defined supraspinal populations, identify a new set of marker genes of use in future experiments, and provide insight into potential differences in cellular and physiological activity across the supraspinal connectome.SIGNIFICANCE STATEMENT The brain communicates with the body through a wide variety of neuronal populations with distinct functions and differential sensitivity to damage and disease. We have used single-nuclei RNA sequencing technology to distinguish patterns of gene expression within a diverse set of neurons that project axons from the mouse brain to the lumbar spinal cord. The results reveal transcriptional differences between populations previously defined on the basis of anatomy, provide new marker genes to facilitate rapid identification of cell type in future work, and suggest distinct responsiveness of different supraspinal populations to external growth and guidance cues.
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Affiliation(s)
- Zachary Beine
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin 53201
| | - Zimei Wang
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin 53201
| | - Pantelis Tsoulfas
- Department of Neurological Surgery, Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida 33136
| | - Murray G Blackmore
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin 53201
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9
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Han M, Yang H, Lu X, Li Y, Liu Z, Li F, Shang Z, Wang X, Li X, Li J, Liu H, Xin T. Three-Dimensional-Cultured MSC-Derived Exosome-Hydrogel Hybrid Microneedle Array Patch for Spinal Cord Repair. NANO LETTERS 2022; 22:6391-6401. [PMID: 35876503 DOI: 10.1021/acs.nanolett.2c02259] [Citation(s) in RCA: 84] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Exosomes derived from mesenchymal stem cells (MSCs) have been proven to exhibit great potentials in spinal cord injury (SCI) therapy. However, conventional two-dimensional (2D) culture will inevitably lead to the loss of stemness of MSCs, which substantially limits the therapeutic potency of MSCs exosomes (2D-Exo). Exosomes derived from three-dimensional culture (3D-Exo) possess higher therapeutic efficiency which have wide applications in spinal cord therapy. Typically, conventional exosome therapy that relies on local repeated injection results in secondary injury and low efficiency. It is urgent to develop a more reliable, convenient, and effective exosome delivery method to achieve constant in situ exosomes release. Herein, we proposed a controlled 3D-exohydrogel hybrid microneedle array patch to achieve SCI repair in situ. Our studies suggested that MSCs with 3D-culturing could maintain their stemness, and consequently, 3D-Exo effectively reduced SCI-induced inflammation and glial scarring. Thus, it is a promising therapeutic strategy for the treatment of SCI.
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Affiliation(s)
- Min Han
- Department of Neurosurgery, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan 250014, P.R. China
- Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan 250117, P.R. China
| | - Hongru Yang
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P.R. China
| | - Xiangdong Lu
- Department of Neurosurgery, People's Hospital Affiliated to Shandong First Medical University, Jinan 250117, P.R. China
| | - Yuming Li
- Department of Neurosurgery, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan 250014, P.R. China
| | - Zihao Liu
- Department of Neurosurgery, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250012, P.R. China
| | - Feng Li
- Department of Neurosurgery, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan 250014, P.R. China
| | - Zehan Shang
- Department of Neurosurgery, Shangdong Provincial Qianfoshan Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250014, P.R. China
| | - Xiaofeng Wang
- Department of Neurosurgery, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan 250014, P.R. China
| | - Xuze Li
- Department of Neurosurgery, Shangdong Provincial Qianfoshan Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250014, P.R. China
| | - Junliang Li
- Department of Neurosurgery, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan 250014, P.R. China
| | - Hong Liu
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P.R. China
- Institute for Advanced Interdisciplinary Research, University of Jinan, Jinan 250022, P.R. China
| | - Tao Xin
- Department of Neurosurgery, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan 250014, P.R. China
- Medical Science and Technology Innovation Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan 250117, P.R. China
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10
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Klimaschewski L, Claus P. Fibroblast Growth Factor Signalling in the Diseased Nervous System. Mol Neurobiol 2021; 58:3884-3902. [PMID: 33860438 PMCID: PMC8280051 DOI: 10.1007/s12035-021-02367-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/19/2021] [Indexed: 12/12/2022]
Abstract
Fibroblast growth factors (FGFs) act as key signalling molecules in brain development, maintenance, and repair. They influence the intricate relationship between myelinating cells and axons as well as the association of astrocytic and microglial processes with neuronal perikarya and synapses. Advances in molecular genetics and imaging techniques have allowed novel insights into FGF signalling in recent years. Conditional mouse mutants have revealed the functional significance of neuronal and glial FGF receptors, not only in tissue protection, axon regeneration, and glial proliferation but also in instant behavioural changes. This review provides a summary of recent findings regarding the role of FGFs and their receptors in the nervous system and in the pathogenesis of major neurological and psychiatric disorders.
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Affiliation(s)
- Lars Klimaschewski
- Department of Anatomy, Histology and Embryology, Institute of Neuroanatomy, Medical University of Innsbruck, Innsbruck, Austria.
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
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11
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Ying Y, Zhang Y, Tu Y, Chen M, Huang Z, Ying W, Wu Q, Ye J, Xiang Z, Wang X, Wang Z, Zhu S. Hypoxia Response Element-Directed Expression of aFGF in Neural Stem Cells Promotes the Recovery of Spinal Cord Injury and Attenuates SCI-Induced Apoptosis. Front Cell Dev Biol 2021; 9:693694. [PMID: 34195203 PMCID: PMC8236866 DOI: 10.3389/fcell.2021.693694] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 05/10/2021] [Indexed: 12/12/2022] Open
Abstract
Reducing neuronal death after spinal cord injury (SCI) is considered to be an important strategy for the renovation of SCI. Studies have shown that, as an important regulator of the development and maintenance of neural structure, acidic fibroblast growth factor (aFGF) has the role of tissue protection and is considered to be an effective drug for the treatment of SCI. Neural stem cells (NSCs) are rendered with the remarkable characteristics to self-replace and differentiate into a variety of cells, so it is promising to be used in cell transplantation therapy. Based on the facts above, our main aim of this research is to explore the role of NSCs expressing aFGF meditated by five hypoxia-responsive elements (5HRE) in the treatment of SCI by constructing AAV–5HRE–aFGF–NSCs and transplanting it into the area of SCI. Our research results showed that AAV–5HRE–aFGF–NSCs can effectively restore the motor function of rats with SCI. This was accomplished by inhibiting the expression of caspase 12/caspase 3 pathway, EIF2α–CHOP pathway, and GRP78 protein to inhibit apoptosis.
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Affiliation(s)
- Yibo Ying
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, China
| | - Yifan Zhang
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yurong Tu
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Min Chen
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Zhiyang Huang
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Weiyang Ying
- Department of Pain Medicine, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Qiuji Wu
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jiahui Ye
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Ziyue Xiang
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xiangyang Wang
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Zhouguang Wang
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, China
| | - Sipin Zhu
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, China
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12
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Devoto C, Lai C, Qu BX, Guedes VA, Leete J, Wilde E, Walker WC, Diaz-Arrastia R, Kenney K, Gill J. Exosomal MicroRNAs in Military Personnel with Mild Traumatic Brain Injury: Preliminary Results from the Chronic Effects of Neurotrauma Consortium Biomarker Discovery Project. J Neurotrauma 2020; 37:2482-2492. [PMID: 32458732 PMCID: PMC7698974 DOI: 10.1089/neu.2019.6933] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Chronic symptoms after mild traumatic brain injury (mTBI) are common among veterans and service members, and represent a significant source of morbidity, with those who sustain multiple mTBIs at greatest risk. Exosomal micro-RNAs (miRNAs), mediators of intercellular communication, may be involved in chronic TBI symptom persistence. Exosomal miRNA (exomiR) was extracted from 153 participants enrolled in the Chronic Effect of Neurotrauma Consortium (CENC) longitudinal study (no TBI, n = 35; ≥ 3 mTBIs (rTBI), n = 45; 1-2 mTBIs, n = 73). Analyses were performed with nCounter® Human miRNA Expression Panels and Ingenuity Pathway Analysis (IPA) for identification of gene networks associated with TBI. Generalized linear models were used to analyze the predictive value of exomiR dysregulation and remote neurobehavioral symptoms. Compared with controls, there were 17 dysregulated exomiRs in the entire mTBI group and 32 dysregulated exomiRs in the rTBI group. Two miRNAs, hsa-miR-139-5p and hsa-miR-18a-5p, were significantly differentially expressed in the rTBI and 1-2 mTBI groups. IPA analyses showed that these dysregulated exomiRs correlated with pathways of inflammatory regulation, neurological disease, and cell development. Within the rTBI group, exomiRs correlated with gene activity for hub-genes of tumor protein TP53, insulin-like growth factor 1 receptor, and transforming growth factor beta. TBI history and neurobehavioral symptom survey scores negatively and significantly correlated with hsa-miR-103a-3p expression. Participants with remote mTBI have distinct exomiR profiles, which are significantly linked to inflammatory and neuronal repair pathways. These profiles suggest that analysis of exosomal miRNA expression may provide novel insights into the underlying pathobiology of chronic TBI symptom persistence.
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Affiliation(s)
- Christina Devoto
- Tissue Injury Branch, National Institutes of Nursing Research, National Institutes of Health, Bethesda, Maryland, USA
- Center for Neuroscience and Rehabilitation Medicine, Uniformed Services University of the Health Sciences and National Institutes of Health, Bethesda, Maryland, USA
| | - Chen Lai
- Tissue Injury Branch, National Institutes of Nursing Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Bao-Xi Qu
- Department of Neurology, Uniformed Services University of the Health Sciences and National Institutes of Health, Bethesda, Maryland, USA
- CENC Biorepository, Uniformed Services University of the Health Sciences, Twinbrook, Rockville, Maryland, USA
| | - Vivian A. Guedes
- Tissue Injury Branch, National Institutes of Nursing Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Jacqueline Leete
- Tissue Injury Branch, National Institutes of Nursing Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Elisabeth Wilde
- CENC Imaging Core, University of Utah, Salt Lake City, Utah, USA
| | - William C. Walker
- Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Ramon Diaz-Arrastia
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Kimbra Kenney
- Department of Neurology, Uniformed Services University of the Health Sciences and National Institutes of Health, Bethesda, Maryland, USA
- CENC Biorepository, Uniformed Services University of the Health Sciences, Twinbrook, Rockville, Maryland, USA
| | - Jessica Gill
- Tissue Injury Branch, National Institutes of Nursing Research, National Institutes of Health, Bethesda, Maryland, USA
- Center for Neuroscience and Rehabilitation Medicine, Uniformed Services University of the Health Sciences and National Institutes of Health, Bethesda, Maryland, USA
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13
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Spinal Reflex Recovery after Dorsal Rhizotomy and Repair with Platelet-Rich Plasma (PRP) Gel Combined with Bioengineered Human Embryonic Stem Cells (hESCs). Stem Cells Int 2020; 2020:8834360. [PMID: 33178285 PMCID: PMC7647752 DOI: 10.1155/2020/8834360] [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: 07/22/2020] [Revised: 09/20/2020] [Accepted: 09/30/2020] [Indexed: 02/07/2023] Open
Abstract
Dorsal root rhizotomy (DRZ) is currently considered an untreatable injury, resulting in the loss of sensitive function and usually leading to neuropathic pain. In this context, we recently proposed a new surgical approach to treat DRZ that uses platelet-rich plasma (PRP) gel to restore the spinal reflex. Success was correlated with the reentry of primary afferents into the spinal cord. Here, aiming to enhance previous results, cell therapy with bioengineered human embryonic stem cells (hESCs) to overexpress fibroblast growth factor 2 (FGF2) was combined with PRP. For these experiments, adult female rats were submitted to a unilateral rhizotomy of the lumbar spinal dorsal roots, which was followed by root repair with PRP gel with or without bioengineered hESCs. One week after DRZ, the spinal cords were processed to evaluate changes in the glial response (GFAP and Iba-1) and excitatory synaptic circuits (VGLUT1) by immunofluorescence. Eight weeks postsurgery, the lumbar intumescences were processed for analysis of the repaired microenvironment by transmission electron microscopy. Spinal reflex recovery was evaluated by the electronic Von Frey method for eight weeks. The transcript levels for human FGF2 were over 37-fold higher in the induced hESCs than in the noninduced and the wildtype counterparts. Altogether, the results indicate that the combination of hESCs with PRP gel promoted substantial and prominent axonal regeneration processes after DRZ. Thus, the repair of dorsal roots, if done appropriately, may be considered an approach to regain sensory-motor function after dorsal root axotomy.
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14
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Systemic treatment with a novel basic fibroblast growth factor mimic small-molecule compound boosts functional recovery after spinal cord injury. PLoS One 2020; 15:e0236050. [PMID: 32678832 PMCID: PMC7367485 DOI: 10.1371/journal.pone.0236050] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 06/26/2020] [Indexed: 11/19/2022] Open
Abstract
Neurotrophic factors have been regarded having promising potentials for neuronal protection and regeneration, and thus promoting beneficial effects of kinesiological functions. They can be suspected to play important roles in cell/tissue grafting for various neural diseases. The clinical applications of such trophic factors to the central nervous system (CNS), however, have caused problematic side effects on account of the distinctive bioactive properties. In the course of developing synthetic compounds reflecting beneficial properties of basic fibroblast growth factor (bFGF), we conducted screening candidates that stimulate to trigger the intracellular tyrosine phosphorylation of FGF receptor and lead to the subsequent intracellular signaling in neurons. A small synthetic molecule SUN13837 was characterized by mimicking the beneficial properties of bFGF, which have been known as its specific activities when applied to CNS. What is more remarkable is that SUN13837 is eliminated the bioactivity to induce cell proliferation of non-neuronal somatic cells. On the bases of studies of pharmacology, behavior, physiology and histology, the present study reports that SUN13837 is characterized as a promising synthetic compound for treatment of devastating damages onto the rat spinal cord.
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15
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Shi YJ, Shi M, Xiao LJ, Li L, Zou LH, Li CY, Zhang QJ, Zhou LF, Ji XC, Huang H, Xi Y, Liu L, Zhang HY, Zhao G, Ma L. Inhibitive Effects of FGF2/FGFR1 Pathway on Astrocyte-Mediated Inflammation in vivo and in vitro After Infrasound Exposure. Front Neurosci 2018; 12:582. [PMID: 30210273 PMCID: PMC6119807 DOI: 10.3389/fnins.2018.00582] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 08/02/2018] [Indexed: 12/31/2022] Open
Abstract
Infrasound, a kind of ambient noise, can cause severe disorders to various human organs, specially to central nervous system (CNS). Our previous studies have shown that infrasound-induced CNS injury was closely related with astrocytes activation and astrocytes-mediated neuroinflammation, but the underlying molecular mechanisms are still largely unclear. FGF2/FGFR1 (Fibroblast growth factor 2/Fibroblast growth factor receptor 1) pathway was reported to play an important role in anti-inflammation in CNS disorders. To further study the possible roles of FGF2/FGFR1 pathway in infrasound-induced CNS injury, here we exposed Sprague-Dawley rats or cultured astrocytes to 16 Hz, 150 dB infrasound, and explored the effects of FGF2 on infrasound-induced astrocytes activation and neuroinflammation. Western blotting, immunofluorescence and liquid chip method were used in this experiment. Our results showed that after 3- or 7-day exposure (2 h/day) of rats as well as 2 h exposure of cultured astrocytes to 16 Hz, 150 dB infrasound, astrocyte-expressed FGFR1 was downregulated in vivo and in vitro. FGF2 pretreatment not only inhibited infrasound-induced astrocyte activation in rat hippocampal CA1 region, but also reduced the levels of pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-18, IL-6, and IFN-γ in vitro and in vivo. However, FGF2 significantly upregulated the expression of FGFR1. Furthermore, we showed that FGF2 could attenuate IκBα phosphorylation, NF-κB p65 translocation, pro-inflammatory cytokines levels, and neuronal loss in the CA1 region induced by infrasound. On the contrary, PD173074, a special antagonist of FGFR1, could reverse the effects above in vitro and in vivo. Taken together, our findings showed that FGF2/FGFR1 pathway may exert inhibitive effects on astrocyte-mediated neuroinflammation in vitro and in vivo after infrasound exposure.
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Affiliation(s)
- Ya-Jun Shi
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.,31668 Troops of PLA, Army Medical University, Xining, China
| | - Ming Shi
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Li-Jun Xiao
- Department of Psychological Medicine, The General Hospital of PLA, Beijing, China
| | - Li Li
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Lin-Hui Zou
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Chao-Yang Li
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Qin-Jun Zhang
- Department of Neurology, Meishan Cardio-Cerebrovascular Disease Hospital, Meishan, China
| | - Lin-Fu Zhou
- Department of Neurology, Third Hospital of PLA, Baoji, China
| | - Xin-Chao Ji
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Huan Huang
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Ye Xi
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Ling Liu
- Department of Neurobiology, School of Basic Medicine, The Fourth Military Medical University, Xi'an, China
| | - Hong-Ya Zhang
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Gang Zhao
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Lei Ma
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
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16
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Abstract
The inability to recover functions lost after severe spinal cord injury has been recognized for millennia and was first attributed to a failure of spinal cord neural regeneration over 100 years ago. The last forty years have seen intense research into achieving such regeneration, but in spite of conceptual advances and many reports announcing successful interventions, progress has been slow and often controversial. Here, I examine consequential advances and setbacks, and critically consider assumptions underlying certain approaches. I argue that expanding mechanistic knowledge about multiple forms of neural regeneration, why they fail and how they can restore function will resolve conceptual contentions and push the field forward.
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