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Yang Y, Suo N, Cui SH, Wu X, Ren XY, Liu Y, Guo R, Xie X. Trametinib, an anti-tumor drug, promotes oligodendrocytes generation and myelin formation. Acta Pharmacol Sin 2024:10.1038/s41401-024-01313-9. [PMID: 38871922 DOI: 10.1038/s41401-024-01313-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Accepted: 05/15/2024] [Indexed: 06/15/2024] Open
Abstract
Oligodendrocytes (OLs) are differentiated from oligodendrocyte precursor cells (OPCs) in the central nervous system (CNS). Demyelination is a common feature of many neurological diseases such as multiple sclerosis (MS) and leukodystrophies. Although spontaneous remyelination can happen after myelin injury, nevertheless, it is often insufficient and may lead to aggravated neurodegeneration and neurological disabilities. Our previous study has discovered that MEK/ERK pathway negatively regulates OPC-to-OL differentiation and remyelination in mouse models. To facilitate possible clinical evaluation, here we investigate several MEK inhibitors which have been approved by FDA for cancer therapies in both mouse and human OPC-to-OL differentiation systems. Trametinib, the first FDA approved MEK inhibitor, displays the best effect in stimulating OL generation in vitro among the four MEK inhibitors examined. Trametinib also significantly enhances remyelination in both MOG-induced EAE model and LPC-induced focal demyelination model. More exciting, trametinib facilitates the generation of MBP+ OLs from human embryonic stem cells (ESCs)-derived OPCs. Mechanism study indicates that trametinib promotes OL generation by reducing E2F1 nuclear translocation and subsequent transcriptional activity. In summary, our studies indicate a similar inhibitory role of MEK/ERK in human and mouse OL generation. Targeting the MEK/ERK pathway might help to develop new therapies or repurpose existing drugs for demyelinating diseases.
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Affiliation(s)
- Ying Yang
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Na Suo
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Shi-Hao Cui
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuan Wu
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Xin-Yue Ren
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yin Liu
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Ren Guo
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, 264117, China
| | - Xin Xie
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China.
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China.
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, 264117, China.
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Emery B, Wood TL. Regulators of Oligodendrocyte Differentiation. Cold Spring Harb Perspect Biol 2024; 16:a041358. [PMID: 38503504 PMCID: PMC11146316 DOI: 10.1101/cshperspect.a041358] [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] [Indexed: 03/21/2024]
Abstract
Myelination has evolved as a mechanism to ensure fast and efficient propagation of nerve impulses along axons. Within the central nervous system (CNS), myelination is carried out by highly specialized glial cells, oligodendrocytes. The formation of myelin is a prolonged aspect of CNS development that occurs well into adulthood in humans, continuing throughout life in response to injury or as a component of neuroplasticity. The timing of myelination is tightly tied to the generation of oligodendrocytes through the differentiation of their committed progenitors, oligodendrocyte precursor cells (OPCs), which reside throughout the developing and adult CNS. In this article, we summarize our current understanding of some of the signals and pathways that regulate the differentiation of OPCs, and thus the myelination of CNS axons.
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Affiliation(s)
- Ben Emery
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Teresa L Wood
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey 07103, USA
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3
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Elitt CM, Ross MM, Wang J, Fahrni CJ, Rosenberg PA. Developmental regulation of zinc homeostasis in differentiating oligodendrocytes. Neurosci Lett 2024; 831:137727. [PMID: 38467270 DOI: 10.1016/j.neulet.2024.137727] [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: 07/09/2023] [Revised: 03/05/2024] [Accepted: 03/08/2024] [Indexed: 03/13/2024]
Abstract
Oligodendrocytes develop through sequential stages and understanding pathways regulating their differentiation remains an important area of investigation. Zinc is required for the function of enzymes, proteins and transcription factors, including those important in myelination and mitosis. Our previous studies using the ratiometric zinc sensor chromis-1 demonstrated a reduction in intracellular free zinc concentrations in mature MBP+ oligodendrocytes compared with earlier stages (Bourassa et al., 2018). We performed a more detailed developmental study to better understand the temporal course of zinc homeostasis across the oligodendrocyte lineage. Using chromis-1, we found a transient increase in free zinc after O4+,O1- pre-oligodendrocytes were switched from proliferation medium into terminal differentiation medium. To gather other evidence for dynamic regulation of free zinc during oligodendrocyte development, qPCR was used to evaluate mRNA expression of major zinc storage proteins metallothioneins (MTs) and metal regulatory transcription factor 1 (MTF1), which controls expression of MTs. MT1, MT2 and MTF1 mRNAs were increased several fold in mature oligodendrocytes compared to oligodendrocytes in proliferation medium. To assess the depth of the zinc buffer, we assayed zinc release from intracellular stores using the oxidizing thiol reagent 2,2'-dithiodipyridine (DTDP). Exposure to DTDP resulted in ∼ 100% increase in free zinc in pre-oligodendrocytes but, paradoxically more modest ∼ 60% increase in mature oligodendrocytes despite increased expression of MTs. These results suggest that zinc homeostasis is regulated during oligodendrocyte development, that oligodendrocytes are a useful model for studying zinc homeostasis in the central nervous system, and that regulation of zinc homeostasis may be important in oligodendrocyte differentiation.
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Affiliation(s)
- Christopher M Elitt
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, United States; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, United States.
| | - Madeline M Ross
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, United States; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, United States
| | - Jianlin Wang
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, United States; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, United States
| | - Christoph J Fahrni
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, United States; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Paul A Rosenberg
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, United States; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, United States
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Han JY, Park J. Paternally Inherited Noonan Syndrome Caused by a PTPN11 Variant May Exhibit Mild Symptoms: A Case Report and Literature Review. Genes (Basel) 2024; 15:445. [PMID: 38674380 PMCID: PMC11050143 DOI: 10.3390/genes15040445] [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: 02/27/2024] [Revised: 03/28/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
BACKGROUND Noonan syndrome (NS)/Noonan syndrome with multiple lentigines (NSML) is commonly characterized by distinct facial features, a short stature, cardiac problems, and a developmental delay of variable degrees. However, as many as 50% of individuals diagnosed with NS/NSML have a mildly affected parent or relative due to variable expressivity and possibly incomplete penetrance of the disorder, and those who are recognized to have NS only after a diagnosis are established in a more obviously affected index case. METHODS In order to collect intergenerational data reported from previous studies, electronic journal databases containing information on the molecular genetics of PTPN11 were searched from 2000 to 2022. RESULTS We present a case of a proband with a PTPN11 variant (c.1492C > T/p.Arg498Trp) inherited from an asymptomatic father, displaying only mild intellectual disability without classical symptoms of NS. Among our cases and the reported NS cases caused by the PTPN11 p.Arg498Trp variant, cardiac abnormalities (6/11), facial dysmorphism (7/11), skin pigmentation (4/11), growth problems (4/11), and sensorineural hearing loss (2/11) have been observed. NS/NSML patients with the PTPN11 p.Arg498Trp variant tend to exhibit relatively lower frequencies of skin pigmentation, facial dysmorphism and cardiac abnormalities and mild symptoms compared to those carrying any other mutated PTPN11. CONCLUSIONS Paternally inherited NS/NSML caused by a PTPN11 p.Arg498Trp variant, including our cases, may exhibit relatively lower frequencies of abnormal features and mild symptoms. This could be ascribed to potential gene-gene interactions, gene-environment interactions, the gender and phenotype of the transmitting parent, or ethnic differences that influence the clinical phenotype.
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Affiliation(s)
- Ji Yoon Han
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea;
| | - Joonhong Park
- Department of Laboratory Medicine, Jeonbuk National University Medical School and Hospital, Jeonju 54907, Republic of Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju 54907, Republic of Korea
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Rajendran R, Rajendran V, Böttiger G, Stadelmann C, Shirvanchi K, von Au L, Bhushan S, Wallendszus N, Schunin D, Westbrock V, Liebisch G, Ergün S, Karnati S, Berghoff M. The small molecule fibroblast growth factor receptor inhibitor infigratinib exerts anti-inflammatory effects and remyelination in a model of multiple sclerosis. Br J Pharmacol 2023; 180:2989-3007. [PMID: 37400950 DOI: 10.1111/bph.16186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 05/07/2023] [Accepted: 05/15/2023] [Indexed: 07/05/2023] Open
Abstract
BACKGROUND AND PURPOSE Fibroblast growth factors and receptors (FGFR) have been shown to modulate inflammation and neurodegeneration in multiple sclerosis (MS). The selective FGFR inhibitor infigratinib has been shown to be effective in cancer models. Here, we investigate the effects of infigratinib on prevention and suppression of first clinical episodes of myelin oligodendrocyte glycoprotein (MOG)35-55 -induced experimental autoimmune encephalomyelitis (EAE) in mice. EXPERIMENTAL APPROACH The FGFR inhibitor infigratinib was given over 10 days from the time of experimental autoimmune encephalomyelitis induction or the onset of symptoms. The effects of infigratinib on proliferation, cytotoxicity and FGFR signalling proteins were studied in lymphocyte cell lines and microglial cells. KEY RESULTS Administration of infigratinib prevented by 40% and inhibited by 65% first clinical episodes of the induced experimental autoimmune encephalomyelitis. In the spinal cord, infiltration of lymphocytes and macrophages/microglia, destruction of myelin and axons were reduced by infigratinib. Infigratinib enhanced the maturation of oligodendrocytes and increased remyelination. In addition, infigratinib resulted in an increase of myelin proteins and a decrease in remyelination inhibitors. Further, lipids associated with neurodegeneration such as lysophosphatidylcholine and ceramide were decreased as were proliferation of T cells and microglial cells. CONCLUSION AND IMPLICATIONS This proof of concept study demonstrates the therapeutic potential of targeting FGFRs in a disease model of multiple sclerosis. Application of oral infigratinib resulted in anti-inflammatory and remyelinating effects. Thus, infigratinib may have the potential to slow disease progression or even to improve the disabling symptoms of multiple sclerosis.
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Affiliation(s)
- Ranjithkumar Rajendran
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Vinothkumar Rajendran
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Gregor Böttiger
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Christine Stadelmann
- Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
| | - Kian Shirvanchi
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Laureen von Au
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Sudhanshu Bhushan
- Institute for Anatomy and Cell Biology, University of Giessen, Giessen, Germany
| | - Natascha Wallendszus
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Darja Schunin
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Victor Westbrock
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
| | - Gerhard Liebisch
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital of Regensburg, Regensburg, Germany
| | - Süleyman Ergün
- Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany
| | - Srikanth Karnati
- Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany
| | - Martin Berghoff
- Experimental Neurology Group, Department of Neurology, University of Giessen, Giessen, Germany
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Li H, Zhang Q, Wan R, Zhou L, Xu X, Xu C, Yu Y, Xu Y, Xiang Y, Tang S. PLPPR4 haploinsufficiency causes neurodevelopmental disorders by disrupting synaptic plasticity via mTOR signalling. J Cell Mol Med 2023; 27:3286-3295. [PMID: 37550884 PMCID: PMC10623522 DOI: 10.1111/jcmm.17899] [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: 04/06/2023] [Revised: 07/20/2023] [Accepted: 07/30/2023] [Indexed: 08/09/2023] Open
Abstract
Phospholipid phosphatase related 4 (PLPPR4), a neuron-specific membrane protein located at the postsynaptic density of glutamatergic synapses, is a putative regulator of neuronal plasticity. However, PLPPR4 dysfunction has not been linked to genetic disorders. In this study, we report three unrelated patients with intellectual disability (ID) or autism spectrum disorder (ASD) who harbour a de novo heterozygous copy number loss of PLPPR4 in 1p21.2p21.3, a heterozygous nonsense mutation in PLPPR4 (NM_014839, c.4C > T, p.Gln2*) and a homozygous splice mutation in PLPPR4 (NM_014839: c.408 + 2 T > C), respectively. Bionano single-molecule optical mapping confirmed PLPPR4 deletion contains no additional pathogenic genes. Our results suggested that the loss of function of PLPPR4 is associated with neurodevelopmental disorders. To test the pathogenesis of PLPPR4, peripheral blood mononuclear cells obtained from the patient with heterozygous deletion of PLPPR4 were induced to specific iPSCs (CHWi001-A) and then differentiated into neurons. The neurons carrying the deletion of PLPPR4 displayed the reduced density of dendritic protrusions, shorter neurites and reduced axon length, suggesting the causal role of PLPPR4 in neurodevelopmental disorders. As the mTOR signalling pathway was essential for regulating the axon maturation and function, we found that mTOR signalling was inhibited with a higher level of p-AKT, p-mTOR and p-ERK1/2, decreased p-PI3K in PLPPR4-iPSCs neurons. Additionally, we found silencing PLPPR4 disturbed the mTOR signalling pathway. Our results suggested PLPPR4 modulates neurodevelopment by affecting the plasticity of neurons via the mTOR signalling pathway.
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Affiliation(s)
- Huanzheng Li
- Human Aging Research InstituteNanchang UniversityNanchangChina
| | | | - Ru Wan
- Wenzhou Central HospitalWenzhouChina
| | - Lili Zhou
- Wenzhou Central HospitalWenzhouChina
| | - Xueqin Xu
- Wenzhou Central HospitalWenzhouChina
| | | | - Yuan Yu
- Wenzhou Central HospitalWenzhouChina
| | - Yunzhi Xu
- Wenzhou Central HospitalWenzhouChina
| | | | - Shaohua Tang
- Wenzhou Central HospitalWenzhouChina
- Pediatric GeneticsZhejiang Provincial People's HospitalHangzhouChina
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Tonev D, Momchilova A. Therapeutic Plasma Exchange and Multiple Sclerosis Dysregulations: Focus on the Removal of Pathogenic Circulatory Factors and Altering Nerve Growth Factor and Sphingosine-1-Phosphate Plasma Levels. Curr Issues Mol Biol 2023; 45:7749-7774. [PMID: 37886933 PMCID: PMC10605592 DOI: 10.3390/cimb45100489] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/21/2023] [Accepted: 09/23/2023] [Indexed: 10/28/2023] Open
Abstract
Multiple sclerosis (MS) is predominantly an immune-mediated disease of the central nervous system (CNS) of unknown etiology with a possible genetic predisposition and effect of certain environmental factors. It is generally accepted that the disease begins with an autoimmune inflammatory reaction targeting oligodendrocytes followed by a rapid depletion of their regenerative capacity with subsequent permanent neurodegenerative changes and disability. Recent research highlights the central role of B lymphocytes and the corresponding IgG and IgM autoantibodies in newly forming MS lesions. Thus, their removal along with the modulation of certain bioactive molecules to improve neuroprotection using therapeutic plasma exchange (TPE) becomes of utmost importance. Recently, it has been proposed to determine the levels and precise effects of both beneficial and harmful components in the serum of MS patients undergoing TPE to serve as markers for appropriate TPE protocols. In this review we discuss some relevant examples, focusing on the removal of pathogenic circulating factors and altering the plasma levels of nerve growth factor and sphingosine-1-phosphate by TPE. Altered plasma levels of the reviewed molecular compounds in response to TPE reflect a successful reduction of the pro-inflammatory burden at the expense of an increase in anti-inflammatory potential in the circulatory and CNS compartments.
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Affiliation(s)
- Dimitar Tonev
- Department of Anesthesiology and Intensive Care, University Hospital “Tzaritza Yoanna—ISUL”, Medical University of Sofia, 1527 Sofia, Bulgaria
| | - Albena Momchilova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Science, 1113 Sofia, Bulgaria;
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Sokol DK, Lahiri DK. APPlications of amyloid-β precursor protein metabolites in macrocephaly and autism spectrum disorder. Front Mol Neurosci 2023; 16:1201744. [PMID: 37799731 PMCID: PMC10548831 DOI: 10.3389/fnmol.2023.1201744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 07/17/2023] [Indexed: 10/07/2023] Open
Abstract
Metabolites of the Amyloid-β precursor protein (APP) proteolysis may underlie brain overgrowth in Autism Spectrum Disorder (ASD). We have found elevated APP metabolites (total APP, secreted (s) APPα, and α-secretase adamalysins in the plasma and brain tissue of children with ASD). In this review, we highlight several lines of evidence supporting APP metabolites' potential contribution to macrocephaly in ASD. First, APP appears early in corticogenesis, placing APP in a prime position to accelerate growth in neurons and glia. APP metabolites are upregulated in neuroinflammation, another potential contributor to excessive brain growth in ASD. APP metabolites appear to directly affect translational signaling pathways, which have been linked to single gene forms of syndromic ASD (Fragile X Syndrome, PTEN, Tuberous Sclerosis Complex). Finally, APP metabolites, and microRNA, which regulates APP expression, may contribute to ASD brain overgrowth, particularly increased white matter, through ERK receptor activation on the PI3K/Akt/mTOR/Rho GTPase pathway, favoring myelination.
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Affiliation(s)
- Deborah K. Sokol
- Department of Neurology, Section of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Debomoy K. Lahiri
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN, United States
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, United States
- Indiana Alzheimer Disease Research Center, Indiana University School of Medicine, Indianapolis, IN, United States
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Elitt CM, Ross MM, Wang J, Fahrni CJ, Rosenberg PA. Developmental regulation of zinc homeostasis in differentiating oligodendrocytes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.26.550230. [PMID: 37546881 PMCID: PMC10402100 DOI: 10.1101/2023.07.26.550230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Oligodendrocytes develop through well characterized stages and understanding pathways regulating their differentiation remains an active area of investigation. Zinc is required for the function of many enzymes, proteins and transcription factors, including those important in myelination and mitosis. Our previous studies using the ratiometric zinc sensor chromis-1 demonstrated a reduction in intracellular free zinc concentrations in mature oligodendrocytes compared with earlier stages (Bourassa et al., 2018). We performed a more detailed developmental study to better understand the temporal course of zinc homeostasis across the oligodendrocyte lineage. Using chromis-1, we found a transient increase in free zinc after developing oligodendrocytes were switched into differentiation medium. To gather other evidence for dynamic regulation of free zinc during oligodendrocyte development, qPCR was used to evaluate mRNA expression of the major zinc storage proteins metallothioneins (MTs), and metal regulatory transcription factor 1 (MTF-1) which controls expression of MTs. MT-1, MT-2 and MTF1 mRNAs were all increased several fold in mature oligodendrocytes compared to developing oligodendrocytes. To assess the depth of the zinc buffer, we assayed zinc release from intracellular stores using the oxidizing thiol reagent 2,2'-dithiodipyridine (DTDP). Exposure to DTDP resulted in a ∼100% increase in free zinc in developing oligodendrocytes but, paradoxically more modest ∼60% increase in mature oligodendrocytes despite the increased expression of MTs. These results suggest that zinc homeostasis is regulated during oligodendrocyte development, that oligodendrocytes are a useful model for studying zinc homeostasis in the central nervous system, and that regulation of zinc homeostasis may be important in oligodendrocyte differentiation.
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10
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Zhao X, Jacob C. Mechanisms of Demyelination and Remyelination Strategies for Multiple Sclerosis. Int J Mol Sci 2023; 24:ijms24076373. [PMID: 37047344 PMCID: PMC10093908 DOI: 10.3390/ijms24076373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 03/19/2023] [Accepted: 03/25/2023] [Indexed: 03/31/2023] Open
Abstract
All currently licensed medications for multiple sclerosis (MS) target the immune system. Albeit promising preclinical results demonstrated disease amelioration and remyelination enhancement via modulating oligodendrocyte lineage cells, most drug candidates showed only modest or no effects in human clinical trials. This might be due to the fact that remyelination is a sophistically orchestrated process that calls for the interplay between oligodendrocyte lineage cells, neurons, central nervous system (CNS) resident innate immune cells, and peripheral immune infiltrates and that this process may somewhat differ in humans and rodent models used in research. To ensure successful remyelination, the recruitment and activation/repression of each cell type should be regulated in a highly organized spatio–temporal manner. As a result, drug candidates targeting one single pathway or a single cell population have difficulty restoring the optimal microenvironment at lesion sites for remyelination. Therefore, when exploring new drug candidates for MS, it is instrumental to consider not only the effects on all CNS cell populations but also the optimal time of administration during disease progression. In this review, we describe the dysregulated mechanisms in each relevant cell type and the disruption of their coordination as causes of remyelination failure, providing an overview of the complex cell interplay in CNS lesion sites.
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11
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Tsuchikawa Y, Kamei N, Sanada Y, Nakamae T, Harada T, Imaizumi K, Akimoto T, Miyaki S, Adachi N. Deficiency of MicroRNA-23-27-24 Clusters Exhibits the Impairment of Myelination in the Central Nervous System. Neural Plast 2023; 2023:8938674. [PMID: 37006814 PMCID: PMC10060068 DOI: 10.1155/2023/8938674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/25/2023] [Accepted: 03/12/2023] [Indexed: 04/04/2023] Open
Abstract
Several microRNAs (miRNAs), including miR-23 and miR-27a have been reportedly involved in regulating myelination in the central nervous system. Although miR-23 and miR-27a form clusters in vivo and the clustered miRNAs are known to perform complementary functions, the role of these miRNA clusters in myelination has not been studied. To investigate the role of miR-23-27-24 clusters in myelination, we generated miR-23-27-24 cluster knockout mice and evaluated myelination in the brain and spinal cord. Our results showed that 10-week-old knockout mice had reduced motor function in the hanging wire test compared to the wild-type mice. At 4 weeks, 10 weeks, and 12 months of age, knockout mice showed reduced myelination compared to wild-type mice. The expression levels of myelin basic protein and myelin proteolipid protein were also significantly lower in the knockout mice compared to the wild-type mice. Although differentiation of oligodendrocyte progenitor cells to oligodendrocytes was not inhibited in the knockout mice, the percentage of oligodendrocytes expressing myelin basic protein was significantly lower in 4-week-old knockout mice than that in wild-type mice. Proteome analysis and western blotting showed increased expression of leucine-zipper-like transcription regulator 1 (LZTR1) and decreased expression of R-RAS and phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) in the knockout mice. In summary, loss of miR-23-27-24 clusters reduces myelination and compromises motor functions in mice. Further, LZTR1, which regulates R-RAS upstream of the ERK1/2 pathway, a signal that promotes myelination, has been identified as a novel target of the miR-23-27-24 cluster in this study.
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Affiliation(s)
- Yuji Tsuchikawa
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
| | - Naosuke Kamei
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
| | - Yohei Sanada
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
- Medical Center for Translational and Clinical Research, Hiroshima University Hospital, Hiroshima 7348551, Japan
| | - Toshio Nakamae
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
| | - Takahiro Harada
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
| | - Takayuki Akimoto
- Faculty of Sport Sciences, Waseda University, Tokorozawa 3591192, Japan
| | - Shigeru Miyaki
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
- Medical Center for Translational and Clinical Research, Hiroshima University Hospital, Hiroshima 7348551, Japan
| | - Nobuo Adachi
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 7348551, Japan
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12
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Michailidou I, Vreijling J, Rumpf M, Loos M, Koopmans B, Vlek N, Straat N, Agaser C, Kuipers TB, Mei H, Baas F, Fluiter K. The systemic inhibition of the terminal complement system reduces neuroinflammation but does not improve motor function in mouse models of CMT1A with overexpressed PMP22. CURRENT RESEARCH IN NEUROBIOLOGY 2023; 4:100077. [PMID: 36926597 PMCID: PMC10011818 DOI: 10.1016/j.crneur.2023.100077] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 12/13/2022] [Accepted: 01/27/2023] [Indexed: 02/07/2023] Open
Abstract
Charcot-Marie-Tooth disease type 1A (CMT1A) is the most prevalent hereditary demyelinating neuropathy. This autosomal, dominantly inherited disease is caused by a duplication on chromosome 17p which includes the peripheral myelin protein 22 (PMP22) gene. There is clinical evidence that the disability in CMT1A is to a large extend due to axonal damage rather than demyelination. Over-expression of PMP22 is recently thought to impede cholesterol trafficking causing a total shutdown of local cholesterol and lipid synthesis in the Schwann cells, thus disturbing their ability to remyelinate. But there is a large variety in disease burden between CMT1A patients with the same genetic defect, indicating the presence of modifying factors that affect disease severity. One of these potential factors is the immune system. Several reports have described patients with co-occurrence of CMT1A with chronic inflammatory demyelinating disease or Guillain-Barré syndrome. We have previously shown in multiple animal models that the innate immune system and specifically the terminal complement system is a driver of inflammatory demyelination. To test the contribution of the terminal complement system to neuroinflammation and disease progression in CMT1A, we inhibited systemic complement C6 in two transgenic mouse models for CMT1A, the C3-PMP22 and C3-PMP22 c-JunP0Cre models. Both models over-express human PMP22, and one (C3-PMP22 c-JunP0Cre) also has a Schwann cell-specific knockout of c-Jun, a crucial regulator of myelination controlling autophagy. We found that systemic inhibition of C6 using antisense oligonucleotides affects the neuroinflammation, Rho GTPase and ERK/MAPK signalling pathways in the CMT1A mouse models. The cholesterol synthesis pathway remained unaffected. Analysis of motor function during treatment with C6 antisense oligonucleotides did not reveal any significant improvement in the CMT1A mouse models. This study shows that the contribution of the terminal complement system to progressive loss of motor function in the CMT1A mouse models tested is limited.
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Affiliation(s)
- Iliana Michailidou
- Dept of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Jeroen Vreijling
- Dept of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Matthijs Rumpf
- Dept of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Maarten Loos
- Sylics (Synaptologics B.V.), Bilthoven, the Netherlands
| | | | - Nina Vlek
- Sylics (Synaptologics B.V.), Bilthoven, the Netherlands
| | - Nina Straat
- Sylics (Synaptologics B.V.), Bilthoven, the Netherlands
| | - Cedrick Agaser
- Sequencing Analysis Support Core, Department of Biomedical Data Sciences LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Thomas B Kuipers
- Sequencing Analysis Support Core, Department of Biomedical Data Sciences LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Hailiang Mei
- Sequencing Analysis Support Core, Department of Biomedical Data Sciences LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Frank Baas
- Dept of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Kees Fluiter
- Dept of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
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13
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Lim RG, Al-Dalahmah O, Wu J, Gold MP, Reidling JC, Tang G, Adam M, Dansu DK, Park HJ, Casaccia P, Miramontes R, Reyes-Ortiz AM, Lau A, Hickman RA, Khan F, Paryani F, Tang A, Ofori K, Miyoshi E, Michael N, McClure N, Flowers XE, Vonsattel JP, Davidson S, Menon V, Swarup V, Fraenkel E, Goldman JE, Thompson LM. Huntington disease oligodendrocyte maturation deficits revealed by single-nucleus RNAseq are rescued by thiamine-biotin supplementation. Nat Commun 2022; 13:7791. [PMID: 36543778 PMCID: PMC9772349 DOI: 10.1038/s41467-022-35388-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
The complexity of affected brain regions and cell types is a challenge for Huntington's disease (HD) treatment. Here we use single nucleus RNA sequencing to investigate molecular pathology in the cortex and striatum from R6/2 mice and human HD post-mortem tissue. We identify cell type-specific and -agnostic signatures suggesting oligodendrocytes (OLs) and oligodendrocyte precursors (OPCs) are arrested in intermediate maturation states. OL-lineage regulators OLIG1 and OLIG2 are negatively correlated with CAG length in human OPCs, and ATACseq analysis of HD mouse NeuN-negative cells shows decreased accessibility regulated by OL maturation genes. The data implicates glucose and lipid metabolism in abnormal cell maturation and identify PRKCE and Thiamine Pyrophosphokinase 1 (TPK1) as central genes. Thiamine/biotin treatment of R6/1 HD mice to compensate for TPK1 dysregulation restores OL maturation and rescues neuronal pathology. Our insights into HD OL pathology spans multiple brain regions and link OL maturation deficits to abnormal thiamine metabolism.
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Affiliation(s)
- Ryan G Lim
- UCI MIND, University of California Irvine, Irvine, CA, USA
| | - Osama Al-Dalahmah
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Jie Wu
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA
| | - Maxwell P Gold
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Guomei Tang
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Miriam Adam
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - David K Dansu
- Advanced Science Research Center at the City University of New York, New York, NY, USA
| | - Hye-Jin Park
- Advanced Science Research Center at the City University of New York, New York, NY, USA
| | - Patrizia Casaccia
- Advanced Science Research Center at the City University of New York, New York, NY, USA
| | | | - Andrea M Reyes-Ortiz
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA
| | - Alice Lau
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA, USA
| | - Richard A Hickman
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Fatima Khan
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Fahad Paryani
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Alice Tang
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Kenneth Ofori
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Emily Miyoshi
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, USA
| | - Neethu Michael
- Department of Pathology, University of California Irvine, Irvine, CA, USA
| | - Nicolette McClure
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, USA
| | - Xena E Flowers
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, New York, NY, USA
| | - Jean Paul Vonsattel
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, New York, NY, USA
| | - Shawn Davidson
- Lewis-Sigler Institute for Integrative Genomics, Princeton, NJ, USA
| | - Vilas Menon
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Vivek Swarup
- UCI MIND, University of California Irvine, Irvine, CA, USA
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, USA
| | - Ernest Fraenkel
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - James E Goldman
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA.
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, New York, NY, USA.
| | - Leslie M Thompson
- UCI MIND, University of California Irvine, Irvine, CA, USA.
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA.
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA, USA.
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, USA.
- Sue and Bill Gross Stem Cell Center University of California Irvine, Irvine, CA, USA.
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14
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Mardani M, Ganji R, Ghasemi N, Kazemi M, Razavi S. Impact of Intraventricular Human Adipose-Derived Stem Cells Transplantation with Pregnenolone Treatment on Remyelination of Corpus Callosum in A Rat Model of Multiple Sclerosis. CELL JOURNAL 2022; 24. [PMID: 36527347 PMCID: PMC9790074 DOI: 10.22074/cellj.2022.8173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Multiple sclerosis (MS) is known as a nerve tissue disorder, which causes demyelination of central nervous system (CNS) fibers. Cell-based treatment is a novel strategy for the treatment of demyelinating diseases such as MS. Adipose-derived stem cells (ADSCs) have neuroprotective and neuroregenerative effects and pregnenolone as a neurosteroid has remarkable roles in neurogenesis. We intend to examine the impact of intraventricular transplantation of human ADSCs and systemic injection of pregnenolone on the remyelination of a rat model cuprizone-induced demyelination. MATERIALS AND METHODS This experimental study was performed on 36 male Wistar rats that received a regular diet and a cuprizone diet for 3 weeks for M.S. induction. Through lipoaspirate surgery, human-ADSCs (hADSCs) were obtained from a patient. Six groups of rats (n=6): healthy, MS, sham, pregnenolone injection, ADSCs transplantation, and pregnenolone injection/ADSCs transplantation were included in this study. For assessment of remyelination, transmission electron microscopy (TEM), immunohistochemistry staining, real-time reverse transcription-polymerase chain reaction (RT-PCR), and enzyme-linked immunosorbent assay (ELISA) were performed. RESULTS TEM outcomes revealed an increase in the thickness of the fibers myelin in the treatment groups (P<0.05). We also observed a significant upregulation of MBP, PDGFR-α, and MOG after treatment with hADSCs and pregnenolone compared to other study groups (P<0.001). These results were confirmed by immunostaining analysis. Moreover, there was no significant difference between the ADSCs/pregnenolone group and the control group regarding the level of MBP, A2B5, and MOG proteins in ELISA. CONCLUSION Our data implied that the remyelination and cell recovery were more improved by intraventricular ADSCs transplantation and pregnenolone injection after inducing a rat model of MS.
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Affiliation(s)
- Mohammad Mardani
- Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran,P.O.Box: 81746-73461Department of Anatomical SciencesSchool of MedicineIsfahan University of Medical
SciencesIsfahanIran
Emails:,
| | - Raosul Ganji
- Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Nazem Ghasemi
- Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Kazemi
- Department of Genetics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shahnaz Razavi
- Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran,P.O.Box: 81746-73461Department of Anatomical SciencesSchool of MedicineIsfahan University of Medical
SciencesIsfahanIran
Emails:,
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15
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Fekete CD, Nishiyama A. Presentation and integration of multiple signals that modulate oligodendrocyte lineage progression and myelination. Front Cell Neurosci 2022; 16:1041853. [PMID: 36451655 PMCID: PMC9701731 DOI: 10.3389/fncel.2022.1041853] [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: 09/11/2022] [Accepted: 10/17/2022] [Indexed: 11/15/2022] Open
Abstract
Myelination is critical for fast saltatory conduction of action potentials. Recent studies have revealed that myelin is not a static structure as previously considered but continues to be made and remodeled throughout adulthood in tune with the network requirement. Synthesis of new myelin requires turning on the switch in oligodendrocytes (OL) to initiate the myelination program that includes synthesis and transport of macromolecules needed for myelin production as well as the metabolic and other cellular functions needed to support this process. A significant amount of information is available regarding the individual intrinsic and extrinsic signals that promote OL commitment, expansion, terminal differentiation, and myelination. However, it is less clear how these signals are made available to OL lineage cells when needed, and how multiple signals are integrated to generate the correct amount of myelin that is needed in a given neural network state. Here we review the pleiotropic effects of some of the extracellular signals that affect myelination and discuss the cellular processes used by the source cells that contribute to the variation in the temporal and spatial availability of the signals, and how the recipient OL lineage cells might integrate the multiple signals presented to them in a manner dialed to the strength of the input.
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16
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Xu X, Zhu Y, Yue C, Yang Q, Zhang Z. Comprehensive Bioinformatics Analysis Combined with Wet-Lab Experiments to Find Target Proteins of Chinese Medicine Monomer. Molecules 2022; 27:molecules27186105. [PMID: 36144838 PMCID: PMC9504604 DOI: 10.3390/molecules27186105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
How to use bioinformatics methods to quickly and accurately locate the effective targets of traditional Chinese medicine monomer (TCM) is still an urgent problem needing to be solved. Here, we used high-throughput sequencing to identify the genes that were up-regulated after cells were treated with TCM monomers and used bioinformatics methods to analyze which transcription factors activated these genes. Then, the binding proteins of these transcription factors were analyzed and cross-analyzed with the docking proteins predicted by small molecule reverse docking software to quickly and accurately determine the monomer’s targets. Followeding this method, we predicted that the TCM monomer Daphnoretin (DT) directly binds to JAK2 with a binding energy of −5.43 kcal/mol, and activates the JAK2/STAT3 signaling transduction pathway. Subsequent Western blotting and in vitro binding and kinase experiments further validated our bioinformatics predictions. Our method provides a new approach for quickly and accurately locating the effective targets of TCM monomers, and we also have discovered for the first time that TCM monomer DT is an agonist of JAK2.
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Affiliation(s)
- Xiaohui Xu
- School of Preclinical Medicine, Wannan Medical College, Wuhu 241002, China
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Yunyi Zhu
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Changling Yue
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Qianwen Yang
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Zhaohuan Zhang
- Department of Laboratory Medicine, Changzheng Hospital, Naval Medical University, Shanghai 200003, China
- Correspondence:
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17
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Piatek P, Lewkowicz N, Michlewska S, Wieczorek M, Bonikowski R, Parchem K, Lewkowicz P, Namiecinska M. Natural fish oil improves the differentiation and maturation of oligodendrocyte precursor cells to oligodendrocytes in vitro after interaction with the blood–brain barrier. Front Immunol 2022; 13:932383. [PMID: 35935952 PMCID: PMC9353075 DOI: 10.3389/fimmu.2022.932383] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/24/2022] [Indexed: 11/15/2022] Open
Abstract
The blood–brain barrier (BBB) tightly controls the microenvironment of the central nervous system (CNS) to allow neurons to function properly. Additionally, emerging studies point to the beneficial effect of natural oils affecting a wide variety of physiological and pathological processes in the human body. In this study, using an in vitro model of the BBB, we tested the influence of natural fish oil mixture (FOM) vs. borage oil (BO), both rich in long-chain polyunsaturated fatty acids (LC-PUFAs) and monounsaturated fatty acids (MUFAs) such as oleic acid (C18:1n9c) or nervonic acid (NA), on human oligodendrocyte precursor cells (hOPCs) during their maturation to oligodendrocytes (OLs) regarding their ability to synthesize myelin peptides and NA. We demonstrated that FOM, opposite to BO, supplemented endothelial cells (ECs) and astrocytes forming the BBB, affecting the function of hOPCs during their maturation. This resulted in improved synthesis of myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG), proteolipid protein (PLP), and NA in mature OLs. This effect is probably the result of BBB cell and hOPC stimulation via free fatty acid receptors (FFARs), which increases insulin growth factor-1 (IGF-1), ciliary neurotrophic factor (CNTF), and brain-derived neurotrophic factor (BDNF) and inhibits fibroblast growth factor 2 (FGF-2) synthesis. The unique formula of fish oil, characterized by much more varied components compared to those of BOs, also improved the enhancement of the tight junction by increasing the expression of claudin-5 and VE-cadherin on ECs. The obtained data justify consideration of naturally derived fish oil intake in human diet as affecting during remyelination.
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Affiliation(s)
- Paweł Piatek
- Department of Immunogenetics, Medical University of Lodz, Lodz, Poland
| | - Natalia Lewkowicz
- Department of Periodontology and Oral Mucosal Diseases, Medical University of Lodz, Lodz, Poland
| | - Sylwia Michlewska
- Laboratory of Microscopic Imaging and Specialized Biological Techniques, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Marek Wieczorek
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Radosław Bonikowski
- Faculty of Biotechnology and Food Sciences, Institute of Natural Products and Cosmetics, Lodz University of Technology, Lodz, Poland
| | - Karol Parchem
- Department of Food Chemistry, Technology and Biotechnology, Faculty of Chemistry, Gdansk University of Technology, Gdansk, Poland
| | - Przemysław Lewkowicz
- Department of Immunogenetics, Medical University of Lodz, Lodz, Poland
- *Correspondence: Przemysław Lewkowicz, ; Magdalena Namiecinska,
| | - Magdalena Namiecinska
- Department of Immunogenetics, Medical University of Lodz, Lodz, Poland
- *Correspondence: Przemysław Lewkowicz, ; Magdalena Namiecinska,
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18
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Tong LY, Deng YB, Du WH, Zhou WZ, Liao XY, Jiang X. Clemastine Promotes Differentiation of Oligodendrocyte Progenitor Cells Through the Activation of ERK1/2 via Muscarinic Receptors After Spinal Cord Injury. Front Pharmacol 2022; 13:914153. [PMID: 35865954 PMCID: PMC9294397 DOI: 10.3389/fphar.2022.914153] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 05/24/2022] [Indexed: 11/13/2022] Open
Abstract
The recovery of spinal cord injury (SCI) is closely associated with the obstruction of oligodendrocyte progenitor cell (OPC) differentiation, which ultimately induces the inability to generate newly formed myelin. To address the concern, drug-based methods may be the most practical and feasible way, possibly applying to clinical therapies for patients with SCI. In our previous study, we found that clemastine treatment preserves myelin integrity, decreases the loss of axons, and improves functional recovery in the SCI model. Clemastine acts as an antagonist of the muscarinic acetylcholine receptor (muscarinic receptor, MR) identified from a string of anti-muscarinic drugs that can enhance oligodendrocyte differentiation and myelin wrapping. However, the effects of clemastine on OPC differentiation through MRs in SCI and the underlying mechanism remain unclear. To explore the possibility, a rat model of SCI was established. To investigate if clemastine could promote the differentiation of OPCs in SCI via MR, the expressions of OPC and mature OL were detected at 7 days post injury (dpi) or at 14 dpi. The significant effect of clemastine on encouraging OPC differentiation was revealed at 14 dpi rather than 7 dpi. Under pre-treatment with the MR agonist cevimeline, the positive role of clemastine on OPC differentiation was partially disrupted. Further studies indicated that clemastine increased the phosphorylation level of extracellular signal–regulated kinase 1/2 (p-ERK1/2) and the expressions of transcription factors, Myrf and Olig2. To determine the relationship among clemastine, ERK1/2 signaling, specified transcription factors, and OPC differentiation, the ERK1/2 signaling was disturbed by U0126. The inhibition of ERK1/2 in SCI rats treated with clemastine decreased the expressions of p-ERK 1/2, Myrf, Olig2, and mature OLs, suggesting that ERK1/2 is required for clemastine on promoting OPC differentiation and that specified transcription factors may be affected by the activity of ERK1/2. Moreover, the impact of clemastine on modulating the level of p-ERK 1/2 was restricted following cevimeline pre-injecting, which provides further evidence that the role of clemastine was mediated by MRs. Altogether, our data demonstrated that clemastine, mediated by MRs, promotes OPC differentiation under the enhancement of Myrf and Olig2 by activating ERK1/2 signaling and suggests a novel therapeutic prospect for SCI recovery.
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Affiliation(s)
- Lu-Yao Tong
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, College of Basic Medicine, Chongqing Medical University, Chongqing, China
| | - Yong-Bing Deng
- Department of Chongqing Emergency Medical Center, Chongqing University Center Hospital, School of Medicine, Chongqing University, Chongqing, China
| | - Wei-Hong Du
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, College of Basic Medicine, Chongqing Medical University, Chongqing, China
| | - Wen-Zhu Zhou
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, College of Basic Medicine, Chongqing Medical University, Chongqing, China
| | - Xin-Yu Liao
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, College of Basic Medicine, Chongqing Medical University, Chongqing, China
| | - Xue Jiang
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, College of Basic Medicine, Chongqing Medical University, Chongqing, China
- *Correspondence: Xue Jiang, ,
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19
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Suo N, He B, Cui S, Yang Y, Wang M, Yuan Q, Xie X. The orphan G protein-coupled receptor GPR149 is a negative regulator of myelination and remyelination. Glia 2022; 70:1992-2008. [PMID: 35758525 DOI: 10.1002/glia.24233] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 06/09/2022] [Accepted: 06/16/2022] [Indexed: 12/14/2022]
Abstract
Myelin sheath, formed by oligodendrocytes (OLs) in the central nervous system (CNS) and Schwann cells in periphery, plays a critical role in supporting neuronal functions. OLs, differentiated from oligodendrocyte precursor cells (OPCs), are important for myelination during development and myelin repair in CNS demyelinating disease. To identify mechanisms of myelin development and remyelination after myelin damage is of great clinical interest. Here we show that the orphan G protein-coupled receptor GPR149, enriched in OPCs, negatively regulate OPC to OL differentiation, myelination, as well as remyelination. The expression of GPR149 is downregulated during OPCs differentiation into OLs. GPR149 deficiency does not affect the number of OPCs, but promotes OPC to OL differentiation which results in earlier development of myelin. In cuprizone-induced demyelination model, GPR149 deficiency significantly enhances myelin regeneration. Further study indicates that GPR149 may regulate OL differentiation and myelin formation via MAPK/ERK pathway. Our study suggests that deleting or blocking GPR149 might be an intriguing way to promote myelin repair in demyelinating diseases.
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Affiliation(s)
- Na Suo
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Bingqing He
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmacy, University of Chinese Academy of Sciences, Beijing, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Shihao Cui
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmacy, University of Chinese Academy of Sciences, Beijing, China
| | - Ying Yang
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmacy, University of Chinese Academy of Sciences, Beijing, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Min Wang
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Qianting Yuan
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Xin Xie
- CAS Key Laboratory of Receptor Research, the National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmacy, University of Chinese Academy of Sciences, Beijing, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
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20
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Molina-Holgado E, Esteban PF, Arevalo-Martin Á, Moreno-Luna R, Molina-Holgado F, Garcia-Ovejero D. Endocannabinoid signaling in oligodendroglia. Glia 2022; 71:91-102. [PMID: 35411970 DOI: 10.1002/glia.24180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 03/10/2022] [Accepted: 03/28/2022] [Indexed: 12/11/2022]
Abstract
In the central nervous system, oligodendrocytes synthesize the myelin, a specialized membrane to wrap axons in a discontinuous way allowing a rapid saltatory nerve impulse conduction. Oligodendrocytes express a number of growth factors and neurotransmitters receptors that allow them to sense the environment and interact with neurons and other glial cells. Depending on the cell cycle stage, oligodendrocytes may respond to these signals by regulating their survival, proliferation, migration, and differentiation. Among these signals are the endocannabinoids, lipidic molecules synthesized from phospholipids in the plasma membrane in response to cell activation. Here, we discuss the evidence showing that oligodendrocytes express a full endocannabinoid signaling machinery involved in physiological oligodendrocyte functions that can be therapeutically exploited to promote remyelination in central nervous system pathologies.
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Affiliation(s)
- Eduardo Molina-Holgado
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | - Pedro F Esteban
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | - Ángel Arevalo-Martin
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | - Rafael Moreno-Luna
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | | | - Daniel Garcia-Ovejero
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
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Garcia-Martin G, Alcover-Sanchez B, Wandosell F, Cubelos B. Pathways Involved in Remyelination after Cerebral Ischemia. Curr Neuropharmacol 2022; 20:751-765. [PMID: 34151767 PMCID: PMC9878953 DOI: 10.2174/1570159x19666210610093658] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 05/05/2021] [Accepted: 05/12/2021] [Indexed: 11/22/2022] Open
Abstract
Brain ischemia, also known as ischemic stroke, occurs when there is a lack of blood supply into the brain. When an ischemic insult appears, both neurons and glial cells can react in several ways that will determine the severity and prognosis. This high heterogeneity of responses has been a major obstacle in developing effective treatments or preventive methods for stroke. Although white matter pathophysiology has not been deeply assessed in stroke, its remodelling can greatly influence the clinical outcome and the disability degree. Oligodendrocytes, the unique cell type implied in CNS myelination, are sensible to ischemic damage. Loss of myelin sheaths can compromise axon survival, so new Oligodendrocyte Precursor Cells are required to restore brain function. Stroke can, therefore, enhance oligodendrogenesis to regenerate those new oligodendrocytes that will ensheath the damaged axons. Given that myelination is a highly complex process that requires coordination of multiple pathways such as Sonic Hedgehog, RTKs or Wnt/β-catenin, we will analyse new research highlighting their importance after brain ischemia. In addition, oligodendrocytes are not isolated cells inside the brain, but rather form part of a dynamic environment of interactions between neurons and glial cells. For this reason, we will put some context into how microglia and astrocytes react against stroke and influence oligodendrogenesis to highlight the relevance of remyelination in the ischemic brain. This will help to guide future studies to develop treatments focused on potentiating the ability of the brain to repair the damage.
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Affiliation(s)
- Gonzalo Garcia-Martin
- Departamento de Biología Molecular and Centro Biología Molecular “Severo Ochoa”, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Berta Alcover-Sanchez
- Departamento de Biología Molecular and Centro Biología Molecular “Severo Ochoa”, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Francisco Wandosell
- Departamento de Biología Molecular and Centro Biología Molecular “Severo Ochoa”, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Beatriz Cubelos
- Departamento de Biología Molecular and Centro Biología Molecular “Severo Ochoa”, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain,Address correspondence to this author at the Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Nicolás Cabrera 1, Universidad Autónoma de Madrid, 28049 Madrid, Spain; Tel: 34-91-1964561; Fax: 34-91-1964420; E-mail:
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22
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Yoon H, Triplet EM, Simon WL, Choi CI, Kleppe LS, De Vita E, Miller AK, Scarisbrick IA. Blocking Kallikrein 6 promotes developmental myelination. Glia 2022; 70:430-450. [PMID: 34626143 PMCID: PMC8732303 DOI: 10.1002/glia.24100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 09/11/2021] [Accepted: 09/13/2021] [Indexed: 11/12/2022]
Abstract
Kallikrein related peptidase 6 (Klk6) is a secreted serine protease highly expressed in oligodendrocytes and implicated in demyelinating conditions. To gain insights into the significance of Klk6 to oligodendrocyte biology, we investigated the impact of global Klk6 gene knockout on CNS developmental myelination using the spinal cord of male and female mice as a model. Results demonstrate that constitutive loss of Klk6 expression accelerates oligodendrocyte differentiation developmentally, including increases in the expression of myelin proteins such as MBP, PLP and CNPase, in the number of CC-1+ mature oligodendrocytes, and myelin thickness by the end of the first postnatal week. Co-ordinate elevations in the pro-myelinating signaling pathways ERK and AKT, expression of fatty acid 2-hydroxylase, and myelin regulatory transcription factor were also observed in the spinal cord of 7d Klk6 knockouts. LC/MS/MS quantification of spinal cord lipids showed sphingosine and sphingomyelins to be elevated in Klk6 knockouts at the peak of myelination. Oligodendrocyte progenitor cells (OPCs)-derived from Klk6 knockouts, or wild type OPCs-treated with a Klk6 inhibitor (DFKZ-251), also showed increased MBP and PLP. Moreover, inhibition of Klk6 in OPC cultures enhanced brain derived neurotrophic factor-driven differentiation. Altogether, these findings suggest that oligodendrocyte-derived Klk6 may operate as an autocrine or paracrine rheostat, or brake, on pro-myelinating signaling serving to regulate myelin homeostasis developmentally and in the adult. These findings document for the first time that inhibition of Klk6 globally, or specifically in oligodendrocyte progenitors, is a strategy to increase early stages of oligodendrocyte differentiation and myelin production in the CNS.
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Affiliation(s)
- Hyesook Yoon
- Department of Physical Medicine and Rehabilitation, Mayo Clinic School of Biomedical Sciences Rochester 55905
| | - Erin M. Triplet
- Regenerative Sciences Program, Mayo Clinic School of Biomedical Sciences Rochester 55905
| | - Whitney L. Simon
- Department of Physical Medicine and Rehabilitation, Mayo Clinic School of Biomedical Sciences Rochester 55905
| | - Chan-Il Choi
- Department of Physical Medicine and Rehabilitation, Mayo Clinic School of Biomedical Sciences Rochester 55905
| | - Laurel S. Kleppe
- Department of Physical Medicine and Rehabilitation, Mayo Clinic School of Biomedical Sciences Rochester 55905
| | - Elena De Vita
- University of Heidelberg, Faculty of Biosciences, 69120 Heidelberg, Germany
- German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Aubry K. Miller
- German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
| | - Isobel A. Scarisbrick
- Department of Physical Medicine and Rehabilitation, Mayo Clinic School of Biomedical Sciences Rochester 55905
- Regenerative Sciences Program, Mayo Clinic School of Biomedical Sciences Rochester 55905
- Department of Physiology and Biomedical Engineering, Minnesota USA 55905
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23
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Wang Y, Pleasure D, Deng W, Guo F. Therapeutic Potentials of Poly (ADP-Ribose) Polymerase 1 (PARP1) Inhibition in Multiple Sclerosis and Animal Models: Concept Revisiting. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2102853. [PMID: 34935305 PMCID: PMC8844485 DOI: 10.1002/advs.202102853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 10/12/2021] [Indexed: 05/05/2023]
Abstract
Poly (ADP-ribose) polymerase 1 (PARP1) plays a fundamental role in DNA repair and gene expression. Excessive PARP1 hyperactivation, however, has been associated with cell death. PARP1 and/or its activity are dysregulated in the immune and central nervous system of multiple sclerosis (MS) patients and animal models. Pharmacological PARP1 inhibition is shown to be protective against immune activation and disease severity in MS animal models while genetic PARP1 deficiency studies reported discrepant results. The inconsistency suggests that the function of PARP1 and PARP1-mediated PARylation may be complex and context-dependent. The article reviews PARP1 functions, discusses experimental findings and possible interpretations of PARP1 in inflammation, neuronal/axonal degeneration, and oligodendrogliopathy, three major pathological components cooperatively determining MS disease course and neurological progression, and points out future research directions. Cell type specific PARP1 manipulations are necessary for revisiting the role of PARP1 in the three pathological components prior to moving PARP1 inhibition into clinical trials for MS therapy.
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Affiliation(s)
- Yan Wang
- Department of NeurologySchool of MedicineUniversity of CaliforniaDavisCA95817USA
- Institute for Pediatric Regenerative MedicineUC Davis School of Medicine/Shriners Hospitals for ChildrenSacramentoCAUSA
| | - David Pleasure
- Department of NeurologySchool of MedicineUniversity of CaliforniaDavisCA95817USA
- Institute for Pediatric Regenerative MedicineUC Davis School of Medicine/Shriners Hospitals for ChildrenSacramentoCAUSA
| | - Wenbin Deng
- School of Pharmaceutical Sciences (Shenzhen)Sun Yat‐sen UniversityGuangzhou510006China
| | - Fuzheng Guo
- Department of NeurologySchool of MedicineUniversity of CaliforniaDavisCA95817USA
- Institute for Pediatric Regenerative MedicineUC Davis School of Medicine/Shriners Hospitals for ChildrenSacramentoCAUSA
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24
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Carvalho E, Morais M, Ferreira H, Silva M, Guimarães S, Pêgo A. A paradigm shift: Bioengineering meets mechanobiology towards overcoming remyelination failure. Biomaterials 2022; 283:121427. [DOI: 10.1016/j.biomaterials.2022.121427] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 01/31/2022] [Accepted: 02/17/2022] [Indexed: 12/14/2022]
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25
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Wen X, Jiao L, Tan H. MAPK/ERK Pathway as a Central Regulator in Vertebrate Organ Regeneration. Int J Mol Sci 2022; 23:ijms23031464. [PMID: 35163418 PMCID: PMC8835994 DOI: 10.3390/ijms23031464] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 02/06/2023] Open
Abstract
Damage to organs by trauma, infection, diseases, congenital defects, aging, and other injuries causes organ malfunction and is life-threatening under serious conditions. Some of the lower order vertebrates such as zebrafish, salamanders, and chicks possess superior organ regenerative capacity over mammals. The extracellular signal-regulated kinases 1 and 2 (ERK1/2), as key members of the mitogen-activated protein kinase (MAPK) family, are serine/threonine protein kinases that are phylogenetically conserved among vertebrate taxa. MAPK/ERK signaling is an irreplaceable player participating in diverse biological activities through phosphorylating a broad variety of substrates in the cytoplasm as well as inside the nucleus. Current evidence supports a central role of the MAPK/ERK pathway during organ regeneration processes. MAPK/ERK signaling is rapidly excited in response to injury stimuli and coordinates essential pro-regenerative cellular events including cell survival, cell fate turnover, migration, proliferation, growth, and transcriptional and translational activities. In this literature review, we recapitulated the multifaceted MAPK/ERK signaling regulations, its dynamic spatio-temporal activities, and the profound roles during multiple organ regeneration, including appendages, heart, liver, eye, and peripheral/central nervous system, illuminating the possibility of MAPK/ERK signaling as a critical mechanism underlying the vastly differential regenerative capacities among vertebrate species, as well as its potential applications in tissue engineering and regenerative medicine.
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26
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Lee A, Kwon OW, Jung KR, Song GJ, Yang HJ. The effects of Korean Red Ginseng-derived components on oligodendrocyte lineage cells: Distinct facilitatory roles of the non-saponin and saponin fractions, and Rb1, in proliferation, differentiation and myelination. J Ginseng Res 2022; 46:104-114. [PMID: 35035243 PMCID: PMC8753459 DOI: 10.1016/j.jgr.2021.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 03/21/2021] [Accepted: 04/21/2021] [Indexed: 12/05/2022] Open
Abstract
Background Abnormalities of myelin, which increases the efficiency of action potential conduction, are found in neurological disorders. Korean Red Ginseng (KRG) demonstrates therapeutic efficacy against some of these conditions, however effects on oligodendrocyte (OL)s are not well known. Here, we examined the effects of KRG-derived components on development and protection of OL-lineage cells. Methods Primary OL precursor cell (OPC) cultures were prepared from neonatal mouse cortex. The protective efficacies of the KRG components were examined against inhibitors of mitochondrial respiratory chain activity. For in vivo function of Rb1 on myelination, after 10 days of oral gavage into adult male mice, forebrains were collected. OPC proliferation were assessed by BrdU incorporation, and differentiation and myelination were examined by qPCR, western blot and immunocytochemistry. Results The non-saponin promoted OPC proliferation, while the saponin promoted differentiation. Both processes were mediated by AKT and extracellular regulated kinase (ERK) signaling. KRG extract, the saponin and non-saponin protected OPCs against oxidative stress, and both KRG extract and the saponin significantly increased the expression of the antioxidant enzyme. Among 11 major ginsenosides tested, Rb1 significantly increased OL membrane size in vitro. Moreover, Rb1 significantly increased myelin formation in adult mouse brain. Conclusion All KRG components prevented OPC deaths under oxidative stress. While non-saponin promoted proliferation, saponin fraction increased differentiation and OL membrane size. Furthermore, among all the tested ginsenosides, Rb1 showed the biggest increase in the membrane size and significantly enhanced myelination in vivo. These results imply therapeutic potentials of KRG and Rb1 for myelin-related disorders.
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Affiliation(s)
- Ahreum Lee
- Korea Institute of Brain Science, Seoul, Republic of Korea.,Department of Integrative Biosciences, University of Brain Education, Cheonan, Republic of Korea
| | - Oh Wook Kwon
- Department of Integrative Biosciences, University of Brain Education, Cheonan, Republic of Korea
| | - Kwi Ryun Jung
- Department of Integrative Biosciences, University of Brain Education, Cheonan, Republic of Korea
| | - Gyun Jee Song
- Translational Brain Research Center, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Republic of Korea
| | - Hyun-Jeong Yang
- Korea Institute of Brain Science, Seoul, Republic of Korea.,Department of Integrative Biosciences, University of Brain Education, Cheonan, Republic of Korea
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Han W, Pan Y, Han Z, Cheng L, Jiang L. Advanced Maternal Age Impairs Myelination in Offspring Rats. Front Pediatr 2022; 10:850213. [PMID: 35311052 PMCID: PMC8927774 DOI: 10.3389/fped.2022.850213] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 02/07/2022] [Indexed: 11/13/2022] Open
Abstract
The effects of advanced maternal age (AMA) on the neurodevelopment of offspring are becoming increasingly important. Myelination is an important aspect of brain development; however, a limited number of studies have focused on the effects of AMA on myelination in offspring. The current study aims to evaluate the association between AMA and myelin sheath development in offspring. We studied the learning and memory function of immature offspring using the novel object recognition test. Then, we investigated the expression of myelin basic protein (MBP) in the immature offspring of young (3-month-old) and old (12-month-old) female rats at different time points (14, 28, and 60 days) after birth with immunofluorescence and western blotting. The myelin sheath ultrastructure was observed with transmission electron microscopy in immature and mature offspring. Extracellular signal-regulated kinase 1 and 2 (ERK1/2) and phosphorylated ERK1/2 (p-ERK1/2) were investigated by western blot in immature offspring at the above time points. AMA impaired the memory function of offspring during early postnatal days. The MBP expression level gradually increased with postnatal development in the offspring of both the AMA and Control (Ctl) groups, but the MBP level in the offspring of the AMA group was lower than that of the Ctl group at 14 days after birth. In addition, the ultrastructure of the myelin sheath was defective in AMA offspring during the early postnatal period; however, the myelin sheath was not significantly affected in offspring during adulthood. Interestingly, ERK phosphorylation at 14 days after birth was lower in AMA offspring than in Ctl offspring. However, ERK phosphorylation at 28 days after birth was higher in AMA offspring than in Ctl offspring. The peak of ERK phosphorylation in the AMA group was abnormal and delayed. Our results indicated that AMA is associated with poor developmental myelin formation in offspring. The ERK signaling pathway may play an essential role in the adverse effects of AMA on the offspring myelin sheath development.
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Affiliation(s)
- Wei Han
- Department of Neurology Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Ya'nan Pan
- Department of Neurology Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Ziyao Han
- Department of Neurology Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Li Cheng
- Department of Neurology Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Li Jiang
- Department of Neurology Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
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Sustained ErbB Activation Causes Demyelination and Hypomyelination by Driving Necroptosis of Mature Oligodendrocytes and Apoptosis of Oligodendrocyte Precursor Cells. J Neurosci 2021; 41:9872-9890. [PMID: 34725188 PMCID: PMC8638686 DOI: 10.1523/jneurosci.2922-20.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 09/27/2021] [Accepted: 10/24/2021] [Indexed: 11/26/2022] Open
Abstract
Oligodendrocytes are vulnerable to genetic and environmental insults and its injury leads to demyelinating diseases. The roles of ErbB receptors in maintaining the CNS myelin integrity are largely unknown. Here, we overactivate ErbB receptors that mediate signaling of either neuregulin (NRG) or epidermal growth factor (EGF) family growth factors and found their synergistic activation caused deleterious outcomes in white matter. Sustained ErbB activation induced by the tetracycline-dependent mouse tool Plp-tTA resulted in demyelination, axonal degeneration, oligodendrocyte precursor cell (OPC) proliferation, astrogliosis, and microgliosis in white matter. Moreover, there was hypermyelination before these inflammatory pathologic events. In contrast, sustained ErbB activation induced by another tetracycline-dependent mouse tool Sox10+/rtTA caused hypomyelination in the corpus callosum and optic nerve, which appeared to be a developmental deficit and did not associate with OPC regeneration, astrogliosis, or microgliosis. By tracing the differentiation states of cells expressing tetracycline-controlled transcriptional activator (tTA)/reverse tTA (rtTA)-dependent transgene or pulse-labeled reporter proteins in vitro and in vivo, we found that Plp-tTA targeted mainly mature oligodendrocytes (MOs), whereas Sox10+/rtTA targeted OPCs and newly-formed oligodendrocytes (NFOs). The distinct phenotypes of mice with ErbB overactivation induced by Plp-tTA and Sox10+/rtTA consolidated their nonoverlapping targeting preferences in the oligodendrocyte lineage, and enabled us to demonstrate that ErbB overactivation in MOs induced necroptosis that caused inflammatory demyelination, whereas in OPCs induced apoptosis that caused noninflammatory hypomyelination. Early interference with aberrant ErbB activation ceased oligodendrocyte deaths and restored myelin development in both mice. This study suggests that aberrant ErbB activation is an upstream pathogenetic mechanism of demyelinating diseases, providing a potential therapeutic target. SIGNIFICANCE STATEMENT Primary oligodendropathy is one of the etiologic mechanisms for multiple sclerosis, and oligodendrocyte necroptosis is a pathologic hallmark in the disease. Moreover, the demyelinating disease is now a broad concept that embraces schizophrenia, in which white matter lesions are an emerging feature. ErbB overactivation has been implicated in schizophrenia by genetic analysis and postmortem studies. This study suggests the etiologic implications of ErbB overactivation in myelin pathogenesis and elucidates the pathogenetic mechanisms.
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The oligodendrocyte-enriched orphan G protein-coupled receptor Gpr62 is dispensable for central nervous system myelination. Neural Dev 2021; 16:6. [PMID: 34844642 PMCID: PMC8630896 DOI: 10.1186/s13064-021-00156-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 11/15/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Myelination is a highly regulated process in the vertebrate central nervous system (CNS) whereby oligodendrocytes wrap axons with multiple layers of insulating myelin in order to allow rapid electrical conduction. Establishing the proper pattern of myelin in neural circuits requires communicative axo-glial interactions, however, the molecular interactions that occur between oligodendrocytes and axons during developmental myelination and myelin maintenance remain to be fully elucidated. Our previous work identified G protein-coupled receptor 62 (Gpr62), an uncharacterized orphan g-protein coupled receptor, as being selectively expressed by mature oligodendrocytes within the CNS, suggesting a potential role in myelination or axoglial interactions. However, no studies to date have assessed the functional requirement for Gpr62 in oligodendrocyte development or CNS myelination. METHODS To address this, we generated a knockout mouse strain lacking the Gpr62 gene. We assessed CNS myelination during both postnatal development and adulthood using immunohistochemistry, electron microscopy and western blot. In addition, we utilized AAV-mediated expression of a tagged Gpr62 in oligodendrocytes to determine the subcellular localization of the protein in vivo. RESULTS We find that virally expressed Gpr62 protein is selectively expressed on the adaxonal myelin layer, suggestive of a potential role for Gpr62 in axo-myelinic signaling. Nevertheless, Gpr62 knockout mice display normal oligodendrocyte numbers and apparently normal myelination within the CNS during both postnatal development and adulthood. CONCLUSIONS We conclude that in spite of being well-placed to mediate neuronal-oligodendrocyte communications, Gpr62 is overall dispensable for CNS myelination.
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Wang Y, Guo F. Group I PAKs in myelin formation and repair of the central nervous system: what, when, and how. Biol Rev Camb Philos Soc 2021; 97:615-639. [PMID: 34811887 DOI: 10.1111/brv.12815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 10/20/2021] [Accepted: 11/04/2021] [Indexed: 11/30/2022]
Abstract
p21-activated kinases (PAKs) are a family of cell division control protein 42/ras-related C3 botulinum toxin substrate 1 (Cdc42/Rac1)-activated serine/threonine kinases. Group I PAKs (PAK1-3) have distinct activation mechanisms from group II PAKs (PAK4-6) and are the focus of this review. In transformed cancer cells, PAKs regulate a variety of cellular processes and molecular pathways which are also important for myelin formation and repair in the central nervous system (CNS). De novo mutations in group I PAKs are frequently seen in children with neurodevelopmental defects and white matter anomalies. Group I PAKs regulate virtually every aspect of neuronal development and function. Yet their functions in CNS myelination and remyelination remain incompletely defined. Herein, we highlight the current understanding of PAKs in regulating cellular and molecular pathways and discuss the status of PAK-regulated pathways in oligodendrocyte development. We point out outstanding questions and future directions in the research field of group I PAKs and oligodendrocyte development.
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Affiliation(s)
- Yan Wang
- Department of Neurology, Shriners Hospitals for Children/School of Medicine, Institute for Pediatric Regenerative Medicine (IPRM), University of California, Davis, 2425 Stockton Blvd, Sacramento, CA, 95817, U.S.A
| | - Fuzheng Guo
- Department of Neurology, Shriners Hospitals for Children/School of Medicine, Institute for Pediatric Regenerative Medicine (IPRM), University of California, Davis, 2425 Stockton Blvd, Sacramento, CA, 95817, U.S.A
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31
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Du W, Deng Y, Jiang R, Tong L, Li R, Jiang X. Clemastine Enhances Myelination, Delays Axonal Loss and Promotes Functional Recovery in Spinal Cord Injury. Neurochem Res 2021; 47:503-515. [PMID: 34661796 PMCID: PMC8827101 DOI: 10.1007/s11064-021-03465-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 09/04/2021] [Accepted: 10/08/2021] [Indexed: 11/24/2022]
Abstract
Recent evidence has shown that demyelination occurs along with axonal degeneration in spinal cord injury (SCI) during the secondary injury phase. Oligodendrocyte precursor cells (OPC) are present in the lesions but fail to differentiate into mature oligodendrocytes and form new myelin. Given the limited recovery of neuronal functions after SCI in adults without effective treatment available so far, it remains unknown whether enhancing OPC differentiation and myelination could benefit the recovery of SCI. To show the significance of myelin regeneration after SCI, the injury was treated with clemastine in the rat model. Clemastine is an FDA-approved drug that is potent in promoting oligodendrocyte differentiation and myelination in vivo, for four weeks following SCI. Motor function was assessed using sloping boards and grid walking tests and scored according to the Basso, Beattie, and Bresnahan protocol. The myelin integrity and protein expression were evaluated using transmission electron microscopy and immunofluorescence, respectively. The results indicated that clemastine treatment preserves myelin integrity, decreases loss of axons and improves functional recovery in the rat SCI model. The presented data suggest that myelination-enhancing strategies may serve as a potential therapeutic approach for the functional recovery in SCI.
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Affiliation(s)
- Weihong Du
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, School of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China
| | - Yongbing Deng
- Department of Chongqing Emergency Medical Center, Chongqing University Center Hospital, School of Medicine, Chongqing University, Chongqing, 400014, China
| | - Rong Jiang
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, School of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China
| | - Luyao Tong
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, School of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China
| | - Ruixue Li
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing, 400038, China
| | - Xue Jiang
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, School of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China.
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32
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Xie Y, Zhang X, Xu P, Zhao N, Zhao Y, Li Y, Hong Y, Peng M, Yuan K, Wan T, Sun R, Chen D, Xu L, Chen J, Guo H, Shan W, Li J, Li R, Xiong Y, Liu D, Wang Y, Liu G, Ye R, Liu X. Aberrant oligodendroglial LDL receptor orchestrates demyelination in chronic cerebral ischemia. J Clin Invest 2021; 131:128114. [PMID: 33141760 DOI: 10.1172/jci128114] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 10/29/2020] [Indexed: 01/09/2023] Open
Abstract
Oligodendrocytes express low-density lipoprotein receptor (LDLR) to endocytose cholesterol for the maintenance of adulthood myelination. However, the potential role of LDLR in chronic cerebral ischemia-related demyelination remains unclear. We used bilateral carotid artery stenosis (BCAS) to induce sustained cerebral ischemia in mice. This hypoxic-ischemic injury caused a remarkable decrease in oligodendroglial LDLR, with impaired oligodendroglial differentiation and survival. Oligodendroglial cholesterol levels, however, remained unchanged. Mouse miR-344e-3p and the human homolog miR-410-3p, 2 miRNAs directly targeting Ldlr, were identified in experimental and clinical leukoaraiosis and were thus implicated in the LDLR reduction. Lentiviral delivery of LDLR ameliorated demyelination following chronic cerebral ischemia. By contrast, Ldlr-/- mice displayed inadequate myelination in the corpus callosum. Ldlr-/- oligodendrocyte progenitor cells (OPCs) exhibited reduced ability to differentiate and myelinate axons in vitro. Transplantation with Ldlr-/- OPCs could not rescue the BCAS-induced demyelination. Such LDLR-dependent myelin restoration might involve a physical interaction of the Asn-Pro-Val-Tyr (NPVY) motif with the phosphotyrosine binding domain of Shc, which subsequently activated the MEK/ERK pathway. Together, our findings demonstrate that the aberrant oligodendroglial LDLR in chronic cerebral ischemia impairs myelination through intracellular signal transduction. Preservation of oligodendroglial LDLR may provide a promising approach to treat ischemic demyelination.
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Affiliation(s)
- Yi Xie
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Xiaohao Zhang
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Pengfei Xu
- Stroke Center & Department of Neurology, The Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Nana Zhao
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Ying Zhao
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Yunzi Li
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Ye Hong
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Mengna Peng
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Kang Yuan
- Department of Neurology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ting Wan
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Rui Sun
- Department of Neurology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Deyan Chen
- Center for Public Health Research, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Lili Xu
- Department of Neurology, Nanjing Brain Hospital Affiliated with Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jingjing Chen
- Department of Neurology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Hongquan Guo
- Department of Neurology, Jinling Hospital, Southern Medical University, Nanjing, Jiangsu, China
| | - Wanying Shan
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Juanji Li
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Rongrong Li
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Yunyun Xiong
- China National Clinical Research Center for Neurological Diseases, Beijing, China.,Vascular Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Dezhi Liu
- Department of Neurology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yuhui Wang
- Institute of Cardiovascular Sciences, School of Basic Medicine, Peking University Health Science Center, Beijing, China
| | - George Liu
- Institute of Cardiovascular Sciences, School of Basic Medicine, Peking University Health Science Center, Beijing, China
| | - Ruidong Ye
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Xinfeng Liu
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China.,Stroke Center & Department of Neurology, The Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
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Binamé F, Pham-Van LD, Bagnard D. Manipulating oligodendrocyte intrinsic regeneration mechanism to promote remyelination. Cell Mol Life Sci 2021; 78:5257-5273. [PMID: 34019104 PMCID: PMC11073109 DOI: 10.1007/s00018-021-03852-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/14/2021] [Accepted: 05/08/2021] [Indexed: 02/06/2023]
Abstract
In demyelinated lesions, astrocytes, activated microglia and infiltrating macrophages secrete several factors regulating oligodendrocyte precursor cells' behaviour. What appears to be the initiation of an intrinsic mechanism of myelin repair is only leading to partial recovery and inefficient remyelination, a process worsening over the course of the disease. This failure is largely due to the concomitant accumulation of inhibitory cues in and around the lesion sites opposing to growth promoting factors. Here starts a complex game of interactions between the signalling pathways controlling oligodendrocytes migration or differentiation. Receptors of positive or negative cues are modulating Ras, PI3K or RhoGTPases pathways acting on oligodendrocyte cytoskeleton remodelling. From the description of this intricate signalling network, this review addresses the extent to which the modulation of the global response to inhibitory cues may pave the route towards novel therapeutic approaches for myelin repair.
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Affiliation(s)
- Fabien Binamé
- INSERM U1119, Biopathology of Myelin, Neuroprotection and Therapeutic Strategy (BMNST Lab), Labex Medalis, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Pôle API, Ecole Supérieure de Biotechnologie, 300 Boulevard Sébastien Brant, 67412, Illkirch, France
| | - Lucas D Pham-Van
- INSERM U1119, Biopathology of Myelin, Neuroprotection and Therapeutic Strategy (BMNST Lab), Labex Medalis, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Pôle API, Ecole Supérieure de Biotechnologie, 300 Boulevard Sébastien Brant, 67412, Illkirch, France
| | - Dominique Bagnard
- INSERM U1119, Biopathology of Myelin, Neuroprotection and Therapeutic Strategy (BMNST Lab), Labex Medalis, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Pôle API, Ecole Supérieure de Biotechnologie, 300 Boulevard Sébastien Brant, 67412, Illkirch, France.
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Gilloteaux J, Bouchat J, Bielarz V, Brion JP, Nicaise C. A primary cilium in oligodendrocytes: a fine structure signal of repairs in thalamic Osmotic Demyelination Syndrome (ODS). Ultrastruct Pathol 2021; 45:128-157. [PMID: 34154511 DOI: 10.1080/01913123.2021.1891161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A murine osmotic demyelination syndrome (ODS) model of the central nervous system included the relay thalamic ventral posterolateral (VPL) and ventral posteromedial (VPM) nuclei. Morphologic comparisons between treatments have revealed oligodendrocyte changes and, already 12 hours following the osmolality restoration, some heavily contrasted oligodendrocytes formed a unique intracellular primary cilium. This unique structure, found in vivo, in mature CNS oligodendrocytes, could account for a local awakening of some of the developmental proteome as it can be expressed in oligodendrocyte precursor cells. This resilience accompanied the emergence of arl13b protein expression along with restoration of nerve cell body axon hillocks shown in a previous issue of this journal. Additionally, the return of several thalamic oligodendrocyte fine features (nucleus, organelles) was shown 36 h later, including some mitosis. Those cell restorations and recognized translational activities comforted that local repairs could again take place, due to oligodendrocyte resilience after ODS instead or added to a postulated immigration of oligodendrocyte precursor cells distant from the sites of myelinolysis.
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Affiliation(s)
- Jacques Gilloteaux
- Unit of Research in Molecular Physiology (Urphym - NARILIS), Départment of Médecine, Université de Namur, Namur, Belgium.,Department of Anatomical Sciences, St George's University School of Medicine, KB Taylor Global Scholar's Program at UNN, School of Health and Life Sciences, Newcastle upon Tyne, UK
| | - Joanna Bouchat
- Unit of Research in Molecular Physiology (Urphym - NARILIS), Départment of Médecine, Université de Namur, Namur, Belgium
| | - Valery Bielarz
- Unit of Research in Molecular Physiology (Urphym - NARILIS), Départment of Médecine, Université de Namur, Namur, Belgium
| | - Jean-Pierre Brion
- Laboratory of Histology, Neuroanatomy and Neuropathology, Faculté de Médecine Université Libre de Bruxelles, Brussels, Belgium
| | - Charles Nicaise
- Unit of Research in Molecular Physiology (Urphym - NARILIS), Départment of Médecine, Université de Namur, Namur, Belgium
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Ishii A, Furusho M, Bansal R. Mek/ERK1/2-MAPK and PI3K/Akt/mTOR signaling plays both independent and cooperative roles in Schwann cell differentiation, myelination and dysmyelination. Glia 2021; 69:2429-2446. [PMID: 34157170 DOI: 10.1002/glia.24049] [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: 12/09/2020] [Revised: 04/29/2021] [Accepted: 06/04/2021] [Indexed: 01/15/2023]
Abstract
Multiple signals are involved in the regulation of developmental myelination by Schwann cells and in the maintenance of a normal myelin homeostasis throughout adult life, preserving the integrity of the axons in the PNS. Recent studies suggest that Mek/ERK1/2-MAPK and PI3K/Akt/mTOR intracellular signaling pathways play important, often overlapping roles in the regulation of myelination in the PNS. In addition, hyperactivation of these signaling pathways in Schwann cells leads to a late onset of various pathological changes in the sciatic nerves. However, it remains poorly understood whether these pathways function independently or sequentially or converge using a common mechanism to facilitate Schwann cell differentiation and myelin growth during development and in causing pathological changes in the adult animals. To address these questions, we analyzed multiple genetically modified mice using simultaneous loss- and constitutive gain-of-function approaches. We found that during development, the Mek/ERK1/2-MAPK pathway plays a primary role in Schwann cell differentiation, distinct from mTOR. However, during active myelination, ERK1/2 is dependent on mTOR signaling to drive the growth of the myelin sheath and regulate its thickness. Finally, our data suggest that peripheral nerve pathology during adulthood caused by hyperactivation of Mek/ERK1/2-MAPK or PI3K is likely to be independent or dependent on mTOR-signaling in different contexts. Thus, this study highlights the complexities in the roles played by two major intracellular signaling pathways in Schwann cells that affect their differentiation, myelination, and later PNS pathology and predicts that potential therapeutic modulation of these pathways in PNS neuropathies could be a complex process.
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Affiliation(s)
- Akihiro Ishii
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut, USA
| | - Miki Furusho
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut, USA
| | - Rashmi Bansal
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut, USA
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Chang J, Lurie RH, Sharma A, Bashir M, Fung CM, Dettman RW, Dizon MLV. Intrauterine growth restriction followed by oxygen support uniquely interferes with genetic regulators of myelination. eNeuro 2021; 8:ENEURO.0263-20.2021. [PMID: 34099489 PMCID: PMC8266217 DOI: 10.1523/eneuro.0263-20.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 03/23/2021] [Accepted: 04/23/2021] [Indexed: 12/24/2022] Open
Abstract
Intrauterine growth restriction (IUGR) and oxygen exposure in isolation and combination adversely affect the developing brain, putting infants at risk for neurodevelopmental disability including cerebral palsy. Rodent models of IUGR and postnatal hyperoxia have demonstrated oligodendroglial injury with subsequent white matter injury (WMI) and motor dysfunction. Here we investigate transcriptomic dysregulation in IUGR with and without hyperoxia exposure to account for the abnormal brain structure and function previously documented. We performed RNA sequencing and analysis using a mouse model of IUGR and found that IUGR, hyperoxia, and the combination of IUGR with hyperoxia (IUGR/hyperoxia) produced distinct changes in gene expression. IUGR in isolation demonstrated the fewest differentially expressed genes compared to control. In contrast, we detected several gene alterations in IUGR/hyperoxia; genes involved in myelination were strikingly downregulated. We also identified changes to specific regulators including TCF7L2, BDNF, SOX2, and DGCR8, through Ingenuity Pathway Analysis, that may contribute to impaired myelination in IUGR/hyperoxia. Our findings show that IUGR with hyperoxia induces unique transcriptional changes in the developing brain. These indicate mechanisms for increased risk for WMI in IUGR infants exposed to oxygen and suggest potential therapeutic targets to improve motor outcomes.Significance StatementThis study demonstrates that perinatal exposures of IUGR and/or postnatal hyperoxia result in distinct transcriptomic changes in the developing brain. In particular, we found that genes involved in normal developmental myelination, myelin maintenance, and remyelination were most dysregulated when IUGR was combined with hyperoxia. Understanding how multiple risk factors lead to WMI is the first step in developing future therapeutic interventions. Additionally, because oxygen exposure is often unavoidable after birth, an understanding of gene perturbations in this setting will increase our awareness of the need for tight control of oxygen use to minimize future motor disability.
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Affiliation(s)
- Jill Chang
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Robert H Lurie
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Abhineet Sharma
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Mirrah Bashir
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Camille M Fung
- University of Utah, Department of Pediatrics, Salt Lake City, Utah, USA
| | - Robert W Dettman
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Maria L V Dizon
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
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Effects of FGFR Tyrosine Kinase Inhibition in OLN-93 Oligodendrocytes. Cells 2021; 10:cells10061318. [PMID: 34070622 PMCID: PMC8228431 DOI: 10.3390/cells10061318] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/20/2021] [Accepted: 05/22/2021] [Indexed: 12/15/2022] Open
Abstract
Fibroblast growth factor (FGF) signaling is involved in the pathogenesis of multiple sclerosis (MS). Data from neuropathology studies suggest that FGF signaling contributes to the failure of remyelination in MS. In MOG35–55-induced EAE, oligodendrocyte-specific deletion of FGFR1 and FGFR2 resulted in a less severe disease course, reduced inflammation, myelin and axon degeneration and changed FGF/FGFR and BDNF/TrkB signaling. Since signaling cascades in oligodendrocytes could not be investigated in the EAE studies, we here aimed to characterize FGFR-dependent oligodendrocyte-specific signaling in vitro. FGFR inhibition was achieved by application of the multi-kinase-inhibitor dovitinib and the FGFR1/2/3-inhibitor AZD4547. Both substances are potent inhibitors of FGF signaling; they are effective in experimental tumor models and patients with malignancies. Effects of FGFR inhibition in oligodendrocytes were studied by immunofluorescence microscopy, protein and gene analyses. Application of the tyrosine kinase inhibitors reduced FGFR1, phosphorylated ERK and Akt expression, and it enhanced BDNF and TrkB expression. Furthermore, the myelin proteins CNPase and PLP were upregulated by FGFR inhibition. In summary, inhibition of FGFR signaling in oligodendrocytes can be achieved by application of tyrosine kinase inhibitors. Decreased phosphorylation of ERK and Akt is associated with an upregulation of BDNF/TrkB signaling, which may be responsible for the increased production of myelin proteins. Furthermore, these data suggest that application of FGFR inhibitors may have the potential to promote remyelination in the CNS.
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Wang X, Su Y, Li T, Yu G, Wang Y, Chen X, Yin C, Tang Z, Yi C, Xiao L, Niu J. Quetiapine promotes oligodendroglial process outgrowth and membrane expansion by orchestrating the effects of Olig1. Glia 2021; 69:1709-1722. [PMID: 33660902 DOI: 10.1002/glia.23986] [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] [Received: 06/11/2020] [Revised: 02/18/2021] [Accepted: 02/18/2021] [Indexed: 01/09/2023]
Abstract
Oligodendroglial lineage cells go through a series of morphological changes before myelination. Prior to myelination, cell processes and membrane structures enlarge by approximately 7,000 times, which is required to support axonal wrapping and myelin segment formation. Failure of these processes leads to maldevelopment and impaired myelination. Quetiapine, an atypical antipsychotic drug, was proved to promote oligodendroglial differentiation and (re)myelination, pending detailed effects and regulatory mechanism. In this study, we showed that quetiapine promotes morphological maturation of oligodendroglial lineage cells and myelin segment formation, and a short-term quetiapine treatment is sufficient to induce these changes. To uncover the underlying mechanism, we examined the effect of quetiapine on the Oligodendrocyte transcription factor 1 (Olig1). We found that quetiapine upregulates Olig1 expression level and promotes nuclear Olig1 translocation to the cytosol, where it functions not as a transcription modulator, but in a way that highly correlates with oligodendrocyte morphological transformation. In addition, quetiapine treatment reverses the negative regulatory effect of the Olig1-regulated G protein-coupled receptor 17 (GPR17) on oligodendroglial morphological maturation. Our results demonstrate that quetiapine enhances oligodendroglial differentiation and myelination by promoting cell morphological transformation. This would shed light on the orchestration of oligodendroglia developmental mechanisms, and provides new targets for further therapeutic research.
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Affiliation(s)
- Xiaorui Wang
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Yixun Su
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Tao Li
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Guangdan Yu
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Yuxin Wang
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Xiaoying Chen
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Chenrui Yin
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Ziqin Tang
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Chenju Yi
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Lan Xiao
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
| | - Jianqin Niu
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China
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Pease-Raissi SE, Chan JR. Building a (w)rapport between neurons and oligodendroglia: Reciprocal interactions underlying adaptive myelination. Neuron 2021; 109:1258-1273. [PMID: 33621477 DOI: 10.1016/j.neuron.2021.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/12/2021] [Accepted: 01/29/2021] [Indexed: 12/27/2022]
Abstract
Myelin, multilayered lipid-rich membrane extensions formed by oligodendrocytes around neuronal axons, is essential for fast and efficient action potential propagation in the central nervous system. Initially thought to be a static and immutable process, myelination is now appreciated to be a dynamic process capable of responding to and modulating neuronal function throughout life. While the importance of this type of plasticity, called adaptive myelination, is now well accepted, we are only beginning to understand the underlying cellular and molecular mechanisms by which neurons communicate experience-driven circuit activation to oligodendroglia and precisely how changes in oligodendrocytes and their myelin refine neuronal function. Here, we review recent findings addressing this reciprocal relationship in which neurons alter oligodendroglial form and oligodendrocytes conversely modulate neuronal function.
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Affiliation(s)
- Sarah E Pease-Raissi
- Weill Institute for Neuroscience, Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA.
| | - Jonah R Chan
- Weill Institute for Neuroscience, Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA.
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Allan KC, Hu LR, Scavuzzo MA, Morton AR, Gevorgyan AS, Cohn EF, Clayton BL, Bederman IR, Hung S, Bartels CF, Madhavan M, Tesar PJ. Non-canonical Targets of HIF1a Impair Oligodendrocyte Progenitor Cell Function. Cell Stem Cell 2021; 28:257-272.e11. [PMID: 33091368 PMCID: PMC7867598 DOI: 10.1016/j.stem.2020.09.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 08/19/2020] [Accepted: 09/29/2020] [Indexed: 12/25/2022]
Abstract
Mammalian cells respond to insufficient oxygen through transcriptional regulators called hypoxia-inducible factors (HIFs). Although transiently protective, prolonged HIF activity drives distinct pathological responses in different tissues. Using a model of chronic HIF1a accumulation in pluripotent-stem-cell-derived oligodendrocyte progenitors (OPCs), we demonstrate that HIF1a activates non-canonical targets to impair generation of oligodendrocytes from OPCs. HIF1a activated a unique set of genes in OPCs through interaction with the OPC-specific transcription factor OLIG2. Non-canonical targets, including Ascl2 and Dlx3, were sufficient to block differentiation through suppression of the oligodendrocyte regulator Sox10. Chemical screening revealed that inhibition of MEK/ERK signaling overcame the HIF1a-mediated block in oligodendrocyte generation by restoring Sox10 expression without affecting canonical HIF1a activity. MEK/ERK inhibition also drove oligodendrocyte formation in hypoxic regions of human oligocortical spheroids. This work defines mechanisms by which HIF1a impairs oligodendrocyte formation and establishes that cell-type-specific HIF1a targets perturb cell function in response to low oxygen.
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Affiliation(s)
- Kevin C. Allan
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Lucille R. Hu
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Marissa A. Scavuzzo
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Andrew R. Morton
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Artur S. Gevorgyan
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Erin F. Cohn
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Benjamin L.L. Clayton
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Ilya R. Bederman
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Stevephen Hung
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Cynthia F. Bartels
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Mayur Madhavan
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Paul J. Tesar
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA.,Lead Contact,Correspondence:
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PAK1 Positively Regulates Oligodendrocyte Morphology and Myelination. J Neurosci 2021; 41:1864-1877. [PMID: 33478987 DOI: 10.1523/jneurosci.0229-20.2021] [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: 01/29/2020] [Revised: 01/04/2021] [Accepted: 01/09/2021] [Indexed: 02/06/2023] Open
Abstract
The actin cytoskeleton is crucial for oligodendrocyte differentiation and myelination. Here we show that p21-activated kinase 1 (PAK1), a well-known actin regulator, promotes oligodendrocyte morphologic change and myelin production in the CNS. A combination of in vitro and in vivo models demonstrated that PAK1 is expressed throughout the oligodendrocyte lineage with highest expression in differentiated oligodendrocytes. Inhibiting PAK1 early in oligodendrocyte development decreased oligodendrocyte morphologic complexity and altered F-actin spreading at the tips of oligodendrocyte progenitor cell processes. Constitutively activating AKT in oligodendrocytes in male and female mice, which leads to excessive myelin wrapping, increased PAK1 expression, suggesting an impact of PAK1 during active myelin wrapping. Furthermore, constitutively activating PAK1 in oligodendrocytes in zebrafish led to an increase in myelin internode length while inhibiting PAK1 during active myelination decreased internode length. As myelin parameters influence conduction velocity, these data suggest that PAK1 may influence communication within the CNS. These data support a model in which PAK1 is a positive regulator of CNS myelination.SIGNIFICANCE STATEMENT Myelin is a critical component of the CNS that provides metabolic support to neurons and also facilitates communication between cells in the CNS. Recent data demonstrate that actin dynamics drives myelin wrapping, but how actin is regulated during myelin wrapping is unknown. The authors investigate the role of the cytoskeletal modulator PAK1 during differentiation and myelination by oligodendrocytes, the myelinating cells of the CNS. They demonstrate that PAK1 promotes oligodendrocyte differentiation and myelination by modulating the cytoskeleton and thereby internode length, thus playing a critical role in the function of the CNS.
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Role of Oligodendrocytes and Myelin in the Pathophysiology of Autism Spectrum Disorder. Brain Sci 2020; 10:brainsci10120951. [PMID: 33302549 PMCID: PMC7764453 DOI: 10.3390/brainsci10120951] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/30/2020] [Accepted: 12/02/2020] [Indexed: 12/12/2022] Open
Abstract
Autism Spectrum Disorder (ASD) is an early neurodevelopmental disorder that involves deficits in interpersonal communication, social interaction, and repetitive behaviors. Although ASD pathophysiology is still uncertain, alterations in the abnormal development of the frontal lobe, limbic areas, and putamen generate an imbalance between inhibition and excitation of neuronal activity. Interestingly, recent findings suggest that a disruption in neuronal connectivity is associated with neural alterations in white matter production and myelination in diverse brain regions of patients with ASD. This review is aimed to summarize the most recent evidence that supports the notion that abnormalities in the oligodendrocyte generation and axonal myelination in specific brain regions are involved in the pathophysiology of ASD. Fundamental molecular mediators of these pathological processes are also examined. Determining the role of alterations in oligodendrogenesis and myelination is a fundamental step to understand the pathophysiology of ASD and identify possible therapeutic targets.
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Vaes JEG, Brandt MJV, Wanders N, Benders MJNL, de Theije CGM, Gressens P, Nijboer CH. The impact of trophic and immunomodulatory factors on oligodendrocyte maturation: Potential treatments for encephalopathy of prematurity. Glia 2020; 69:1311-1340. [PMID: 33595855 PMCID: PMC8246971 DOI: 10.1002/glia.23939] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 12/11/2022]
Abstract
Encephalopathy of prematurity (EoP) is a major cause of morbidity in preterm neonates, causing neurodevelopmental adversities that can lead to lifelong impairments. Preterm birth-related insults, such as cerebral oxygen fluctuations and perinatal inflammation, are believed to negatively impact brain development, leading to a range of brain abnormalities. Diffuse white matter injury is a major hallmark of EoP and characterized by widespread hypomyelination, the result of disturbances in oligodendrocyte lineage development. At present, there are no treatment options available, despite the enormous burden of EoP on patients, their families, and society. Over the years, research in the field of neonatal brain injury and other white matter pathologies has led to the identification of several promising trophic factors and cytokines that contribute to the survival and maturation of oligodendrocytes, and/or dampening neuroinflammation. In this review, we discuss the current literature on selected factors and their therapeutic potential to combat EoP, covering a wide range of in vitro, preclinical and clinical studies. Furthermore, we offer a future perspective on the translatability of these factors into clinical practice.
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Affiliation(s)
- Josine E G Vaes
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands.,Department of Neonatology, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands
| | - Myrna J V Brandt
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands
| | - Nikki Wanders
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands
| | - Manon J N L Benders
- Department of Neonatology, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands
| | - Caroline G M de Theije
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands
| | | | - Cora H Nijboer
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children's Hospital, Utrecht University, Utrecht, The Netherlands
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44
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Adams KL, Dahl KD, Gallo V, Macklin WB. Intrinsic and extrinsic regulators of oligodendrocyte progenitor proliferation and differentiation. Semin Cell Dev Biol 2020; 116:16-24. [PMID: 34110985 DOI: 10.1016/j.semcdb.2020.10.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 09/30/2020] [Accepted: 10/01/2020] [Indexed: 12/14/2022]
Abstract
Oligodendrocytes are highly specialized glial cells, responsible for producing myelin in the central nervous system (CNS). The multi-stage process of oligodendrocyte development is tightly regulated to ensure proper lineage progression of oligodendrocyte progenitor cells (OPCs) to mature myelin producing oligodendrocytes. This developmental process involves complex interactions between several intrinsic signaling pathways that are modulated by an array of extrinsic factors. Understanding these regulatory processes is of crucial importance, as it may help to identify specific molecular targets both to enhance plasticity in the normal CNS and to promote endogenous recovery following injury or disease. This review describes two major regulators that play important functional roles in distinct phases of oligodendrocyte development: OPC proliferation and differentiation. Specifically, we highlight the roles of the extracellular astrocyte/radial glia-derived protein Endothelin-1 in OPC proliferation and the intracellular Akt/mTOR pathway in OPC differentiation. Lastly, we reflect on how recent advances in neuroscience and scientific technology will enable greater understanding into how intrinsic and extrinsic regulators interact to generate oligodendrocyte diversity.
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Affiliation(s)
- Katrina L Adams
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, Washington, DC 20010, USA
| | - Kristin D Dahl
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, Washington, DC 20010, USA
| | - Wendy B Macklin
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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45
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Richards K, Jancovski N, Hanssen E, Connelly A, Petrou S. Atypical myelinogenesis and reduced axon caliber in the Scn1a variant model of Dravet syndrome: An electron microscopy pilot study of the developing and mature mouse corpus callosum. Brain Res 2020; 1751:147157. [PMID: 33069731 DOI: 10.1016/j.brainres.2020.147157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 09/26/2020] [Accepted: 10/12/2020] [Indexed: 11/24/2022]
Abstract
Dravet Syndrome (DS) is a genetic neurodevelopmental disease. Recurrent severe seizures begin in infancy and co-morbidities follow, including developmental delay, cognitive and behavioral dysfunction. A majority of DS patients have an SCN1A heterozygous gene mutation. This mutation causes a loss-of-function in inhibitory neurons, initiating seizure onset. We have investigated whether the sodium channelopathy may result in structural changes in the DS model independent of seizures. Morphometric analyses of axons within the corpus callosum were completed at P16 and P50 in Scn1a heterozygote KO male mice and their age-matched wild-type littermates. Trainable machine learning algorithms were used to examine electron microscopy images of ~400 myelinated axons per animal, per genotype, including myelinated axon cross-section area, frequency distribution and g-ratios. Pilot data for Scn1a heterozygote KO mice demonstrate the average axon caliber was reduced in developing and adult mice. Qualitative analysis also shows micro-features marking altered myelination at P16 in the DS model, with myelin out-folding and myelin debris within phagocytic cells. The data has indicated, in the absence of behavioral seizures, factors that governed a shift toward small calibre axons at P16 have persisted in adult Scn1a heterozygote KO corpus callosum. The pilot study provides a basis for future meta-analysis that will enable robust estimates of the effects of the sodium channelopathy on axon architecture. We propose that early therapeutic strategies in DS could help minimize the effect of sodium channelopathies, beyond the impact of overt seizures, and therefore achieve better long-term treatment outcomes.
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Affiliation(s)
- Kay Richards
- Florey Institute of Neuroscience and Mental Health, Australia
| | | | - Eric Hanssen
- Bio21 Advanced Microscopy Facility, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Australia
| | - Alan Connelly
- Florey Institute of Neuroscience and Mental Health, Australia; Florey Institute of Neuroscience and Mental Health, The Florey Department of Neuroscience and Mental Health, University of Melbourne, Australia
| | - Steve Petrou
- Florey Institute of Neuroscience and Mental Health, Australia.
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Nocera G, Jacob C. Mechanisms of Schwann cell plasticity involved in peripheral nerve repair after injury. Cell Mol Life Sci 2020; 77:3977-3989. [PMID: 32277262 PMCID: PMC7532964 DOI: 10.1007/s00018-020-03516-9] [Citation(s) in RCA: 195] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 03/09/2020] [Accepted: 03/30/2020] [Indexed: 01/01/2023]
Abstract
The great plasticity of Schwann cells (SCs), the myelinating glia of the peripheral nervous system (PNS), is a critical feature in the context of peripheral nerve regeneration following traumatic injuries and peripheral neuropathies. After a nerve damage, SCs are rapidly activated by injury-induced signals and respond by entering the repair program. During the repair program, SCs undergo dynamic cell reprogramming and morphogenic changes aimed at promoting nerve regeneration and functional recovery. SCs convert into a repair phenotype, activate negative regulators of myelination and demyelinate the damaged nerve. Moreover, they express many genes typical of their immature state as well as numerous de-novo genes. These genes modulate and drive the regeneration process by promoting neuronal survival, damaged axon disintegration, myelin clearance, axonal regrowth and guidance to their former target, and by finally remyelinating the regenerated axon. Many signaling pathways, transcriptional regulators and epigenetic mechanisms regulate these events. In this review, we discuss the main steps of the repair program with a particular focus on the molecular mechanisms that regulate SC plasticity following peripheral nerve injury.
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Affiliation(s)
- Gianluigi Nocera
- Faculty of Biology, Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, Mainz, Germany
| | - Claire Jacob
- Faculty of Biology, Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, Mainz, Germany.
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47
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R-Ras GTPases Signaling Role in Myelin Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21165911. [PMID: 32824627 PMCID: PMC7460555 DOI: 10.3390/ijms21165911] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/13/2020] [Accepted: 08/14/2020] [Indexed: 12/18/2022] Open
Abstract
Myelination is required for fast and efficient synaptic transmission in vertebrates. In the central nervous system, oligodendrocytes are responsible for creating myelin sheaths that isolate and protect axons, even throughout adulthood. However, when myelin is lost, the failure of remyelination mechanisms can cause neurodegenerative myelin-associated pathologies. From oligodendrocyte progenitor cells to mature myelinating oligodendrocytes, myelination is a highly complex process that involves many elements of cellular signaling, yet many of the mechanisms that coordinate it, remain unknown. In this review, we will focus on the three major pathways involved in myelination (PI3K/Akt/mTOR, ERK1/2-MAPK, and Wnt/β-catenin) and recent advances describing the crosstalk elements which help to regulate them. In addition, we will review the tight relation between Ras GTPases and myelination processes and discuss its potential as novel elements of crosstalk between the pathways. A better understanding of the crosstalk elements orchestrating myelination mechanisms is essential to identify new potential targets to mitigate neurodegeneration.
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Sampaio-Baptista C, Vallès A, Khrapitchev AA, Akkermans G, Winkler AM, Foxley S, Sibson NR, Roberts M, Miller K, Diamond ME, Martens GJM, De Weerd P, Johansen-Berg H. White matter structure and myelin-related gene expression alterations with experience in adult rats. Prog Neurobiol 2020; 187:101770. [PMID: 32001310 PMCID: PMC7086231 DOI: 10.1016/j.pneurobio.2020.101770] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 12/19/2019] [Accepted: 01/24/2020] [Indexed: 11/30/2022]
Abstract
White matter (WM) plasticity during adulthood is a recently described phenomenon by which experience can shape brain structure. It has been observed in humans using diffusion tensor imaging (DTI) and myelination has been suggested as a possible mechanism. Here, we set out to identify molecular and cellular changes associated with WM plasticity measured by DTI. We combined DTI, immunohistochemistry and mRNA expression analysis and examined the effects of somatosensory experience in adult rats. First, we observed experience-induced DTI differences in WM and in grey matter structure. C-Fos mRNA expression, a marker of cortical activity, in the barrel cortex correlated with the MRI WM metrics, indicating that molecular correlates of cortical activity relate to macroscale measures of WM structure. Analysis of myelin-related genes revealed higher myelin basic protein (MBP) mRNA expression. Higher MBP protein expression was also found via immunohistochemistry in WM. Finally, unbiased RNA sequencing analysis identified 134 differentially expressed genes encoding proteins involved in functions related to cell proliferation and differentiation, regulation of myelination and neuronal activity modulation. In conclusion, macroscale measures of WM plasticity are supported by both molecular and cellular evidence and confirm that myelination is one of the underlying mechanisms.
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Affiliation(s)
- Cassandra Sampaio-Baptista
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK.
| | - Astrid Vallès
- Department of Molecular Animal Physiology, Donders Institute for Brain, Cognition and Behaviour, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands; Department of Neurocognition, Faculty of Psychology and Neurosciences, Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Alexandre A Khrapitchev
- Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
| | - Guus Akkermans
- Department of Molecular Animal Physiology, Donders Institute for Brain, Cognition and Behaviour, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands
| | - Anderson M Winkler
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Sean Foxley
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Nicola R Sibson
- Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
| | - Mark Roberts
- Department of Neurocognition, Faculty of Psychology and Neurosciences, Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Karla Miller
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Mathew E Diamond
- Tactile Perception and Learning Lab, International School for Advanced Studies (SISSA), 34136 Trieste, Italy
| | - Gerard J M Martens
- Department of Molecular Animal Physiology, Donders Institute for Brain, Cognition and Behaviour, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands
| | - Peter De Weerd
- Department of Neurocognition, Faculty of Psychology and Neurosciences, Maastricht University, 6200 MD Maastricht, The Netherlands; Department of Cognitive Neuroscience, Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, 6500 HB Nijmegen, The Netherlands; Maastricht Centre for Systems Biology (MaCSBio), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Heidi Johansen-Berg
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
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49
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Kim J, Adams AA, Gokina P, Zambrano B, Jayakumaran J, Dobrowolski R, Maurel P, Pfister BJ, Kim HA. Mechanical stretch induces myelin protein loss in oligodendrocytes by activating Erk1/2 in a calcium-dependent manner. Glia 2020; 68:2070-2085. [PMID: 32170885 DOI: 10.1002/glia.23827] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 03/02/2020] [Accepted: 03/04/2020] [Indexed: 12/15/2022]
Abstract
Myelin loss in the brain is a common occurrence in traumatic brain injury (TBI) that results from impact-induced acceleration forces to the head. Fast and abrupt head motions, either resulting from violent blows and/or jolts, cause rapid stretching of the brain tissue, and the long axons within the white matter tracts are especially vulnerable to such mechanical strain. Recent studies have shown that mechanotransduction plays an important role in regulating oligodendrocyte progenitors cell differentiation into oligodendrocytes. However, little is known about the impact of mechanical strain on mature oligodendrocytes and the stability of their associated myelin sheaths. We used an in vitro cellular stretch device to address these questions, as well as characterize a mechanotransduction mechanism that mediates oligodendrocyte responses. Mechanical stretch caused a transient and reversible myelin protein loss in oligodendrocytes. Cell death was not observed. Myelin protein loss was accompanied by an increase in intracellular Ca2+ and Erk1/2 activation. Chelating Ca2+ or inhibiting Erk1/2 activation was sufficient to block the stretch-induced loss of myelin protein. Further biochemical analyses revealed that the stretch-induced myelin protein loss was mediated by the release of Ca2+ from the endoplasmic reticulum (ER) and subsequent Ca2+ -dependent activation of Erk1/2. Altogether, our findings characterize an Erk1/2-dependent mechanotransduction mechanism in mature oligodendrocytes that de-stabilizes the myelination program.
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Affiliation(s)
- Jihyun Kim
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | - Alexandra A Adams
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | - Pradeepa Gokina
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | - Brayan Zambrano
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | | | - Radek Dobrowolski
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | - Patrice Maurel
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
| | - Bryan J Pfister
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, Newark, New Jersey, USA
| | - Haesun A Kim
- Department of Biological Sciences, Rutgers University, Newark, New Jersey, USA
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50
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Mechanistic Target of Rapamycin Regulates the Oligodendrocyte Cytoskeleton during Myelination. J Neurosci 2020; 40:2993-3007. [PMID: 32139584 DOI: 10.1523/jneurosci.1434-18.2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 02/23/2020] [Accepted: 02/26/2020] [Indexed: 12/22/2022] Open
Abstract
During differentiation, oligodendrocyte precursor cells (OPCs) extend a network of processes that make contact with axons and initiate myelination. Recent studies revealed that actin polymerization is required for initiation of myelination whereas actin depolymerization promotes myelin wrapping. Here, we used primary OPCs in culture isolated from neonatal rat cortices of both sexes and young male and female mice with oligodendrocyte-specific deletion of mechanistic target of rapamycin (mTOR) to demonstrate that mTOR regulates expression of specific cytoskeletal targets and actin reorganization in oligodendrocytes during developmental myelination. Loss or inhibition of mTOR reduced expression of profilin2 and ARPC3, actin polymerizing factors, and elevated levels of active cofilin, which mediates actin depolymerization. The deficits in actin polymerization were revealed in reduced phalloidin and deficits in oligodendrocyte cellular branching complexity at the peak of morphologic differentiation and a delay in initiation of myelination. We further show a critical role for mTOR in expression and localization of myelin basic protein (Mbp) mRNA and MBP protein to the cellular processes where it is necessary at the myelin membrane for axon wrapping. Mbp mRNA transport deficits were confirmed by single molecule RNA FISH. Moreover, expression of the kinesin family member 1B, an Mbp mRNA transport protein, was reduced in CC1+ cells in the mTOR cKO and in mTOR inhibited oligodendrocytes undergoing differentiation in vitro These data support the conclusion that mTOR regulates both initiation of myelination and axon wrapping by targeting cytoskeletal reorganization and MBP localization to oligodendrocyte processes.SIGNIFICANCE STATEMENT Myelination is essential for normal CNS development and adult axon preservation and function. The mechanistic target of rapamycin (mTOR) signaling pathway has been implicated in promoting CNS myelination; however, there is a gap in our understanding of the mechanisms by which mTOR promotes developmental myelination through regulating specific downstream targets. Here, we present evidence that mTOR promotes the initiation of myelination through regulating specific cytoskeletal targets and cellular process expansion by oligodendrocyte precursor cells as well as expression and cellular localization of myelin basic protein.
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