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Ratan Y, Rajput A, Pareek A, Pareek A, Kaur R, Sonia S, Kumar R, Singh G. Recent Advances in Biomolecular Patho-Mechanistic Pathways behind the Development and Progression of Diabetic Neuropathy. Biomedicines 2024; 12:1390. [PMID: 39061964 PMCID: PMC11273858 DOI: 10.3390/biomedicines12071390] [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: 05/07/2024] [Revised: 06/12/2024] [Accepted: 06/19/2024] [Indexed: 07/28/2024] Open
Abstract
Diabetic neuropathy (DN) is a neurodegenerative disorder that is primarily characterized by distal sensory loss, reduced mobility, and foot ulcers that may potentially lead to amputation. The multifaceted etiology of DN is linked to a range of inflammatory, vascular, metabolic, and other neurodegenerative factors. Chronic inflammation, endothelial dysfunction, and oxidative stress are the three basic biological changes that contribute to the development of DN. Although our understanding of the intricacies of DN has advanced significantly over the past decade, the distinctive mechanisms underlying the condition are still poorly understood, which may be the reason behind the lack of an effective treatment and cure for DN. The present study delivers a comprehensive understanding and highlights the potential role of the several pathways and molecular mechanisms underlying the etiopathogenesis of DN. Moreover, Schwann cells and satellite glial cells, as integral factors in the pathogenesis of DN, have been enlightened. This work will motivate allied research disciplines to gain a better understanding and analysis of the current state of the biomolecular mechanisms behind the pathogenesis of DN, which will be essential to effectively address every facet of DN, from prevention to treatment.
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Affiliation(s)
- Yashumati Ratan
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Aishwarya Rajput
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Ashutosh Pareek
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Aaushi Pareek
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Ranjeet Kaur
- Adesh Institute of Dental Sciences and Research, Bathinda 151101, Punjab, India;
| | - Sonia Sonia
- Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar 143005, Punjab, India;
| | - Rahul Kumar
- Baba Ragav Das Government Medical College, Gorakhpur 273013, Uttar Pradesh, India;
| | - Gurjit Singh
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA
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2
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Scherer SS, Svaren J. Peripheral Nervous System (PNS) Myelin Diseases. Cold Spring Harb Perspect Biol 2024; 16:a041376. [PMID: 38253417 PMCID: PMC11065170 DOI: 10.1101/cshperspect.a041376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
This is a review of inherited and acquired causes of human demyelinating neuropathies and a subset of disorders that affect axon-Schwann cell interactions. Nearly all inherited demyelinating neuropathies are caused by mutations in genes that are expressed by myelinating Schwann cells, affecting diverse functions in a cell-autonomous manner. The most common acquired demyelinating neuropathies are Guillain-Barré syndrome and chronic, inflammatory demyelinating polyneuropathy, both of which are immune-mediated. An additional group of inherited and acquired disorders affect axon-Schwann cell interactions in the nodal region. Overall, these disorders affect the formation of myelin and its maintenance, with superimposed axonal loss that is clinically important.
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Affiliation(s)
- Steven S Scherer
- Department of Neurology, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - John Svaren
- Department of Comparative Biosciences, Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
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3
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Trimarco A, Audano M, Marca RL, Cariello M, Falco M, Pedretti S, Imperato G, Cestaro A, Podini P, Dina G, Quattrini A, Massimino L, Caruso D, Mitro N, Taveggia C. Prostaglandin D2 synthase controls Schwann cells metabolism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.29.582775. [PMID: 38496560 PMCID: PMC10942270 DOI: 10.1101/2024.02.29.582775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
We previously reported that in the absence of Prostaglandin D2 synthase (L-PGDS) peripheral nerves are hypomyelinated in development and that with aging they present aberrant myelin sheaths. We now demonstrate that L-PGDS expressed in Schwann cells is part of a coordinated program aiming at preserving myelin integrity. In vivo and in vitro lipidomic, metabolomic and transcriptomic analyses confirmed that myelin lipids composition, Schwann cells energetic metabolism and key enzymes controlling these processes are altered in the absence of L-PGDS. Moreover, Schwann cells undergo a metabolic rewiring and turn to acetate as the main energetic source. Further, they produce ketone bodies to ensure glial cell and neuronal survival. Importantly, we demonstrate that all these changes correlate with morphological myelin alterations and describe the first physiological pathway implicated in preserving PNS myelin. Collectively, we posit that myelin lipids serve as a reservoir to provide ketone bodies, which together with acetate represent the adaptive substrates Schwann cells can rely on to sustain the axo-glial unit and preserve the integrity of the PNS.
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Shan F, Zhang N, Yao X, Li Y, Wang Z, Zhang C, Wang Y. Mechanosensitive channel of large conductance enhances the mechanical stretching-induced upregulation of glycolysis and oxidative metabolism in Schwann cells. Cell Commun Signal 2024; 22:93. [PMID: 38302971 PMCID: PMC10835878 DOI: 10.1186/s12964-024-01497-x] [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: 12/29/2023] [Accepted: 01/21/2024] [Indexed: 02/03/2024] Open
Abstract
BACKGROUND Physical exercise directly stretching the peripheral nerve promotes nerve regeneration; however, its action mechanism remains elusive. Our present study aimed to investigate the effects of mechanosensitive channel of large conductance (MscL) activated by mechanical stretching on the cultured Schwann cells (SCs) and explore the possible mechanism. METHODS Primary SCs from neonatal mice at 3-5 days of age were derived and transfected with the lentivirus vector expressing a mutant version of MscL, MscL-G22S. We first detected the cell viability and calcium ion (Ca2+) influx in the MscL-G22S-expressing SCs with low-intensity mechanical stretching and the controls. Proteomic and energy metabolomics analyses were performed to investigate the comprehensive effects of MscL-G22S activation on SCs. Measurement of glycolysis- and oxidative phosphorylation-related molecules and ATP production were respectively performed to further validate the effects of MscL-G22S activation on SCs. Finally, the roles of phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway in the mechanism of energy metabolism modulation of SCs by MscL-G22S activation was investigated. RESULTS Mechanical stretching-induced MscL-G22S activation significantly increased the cell viability and Ca2+ influx into the SCs. Both the proteomic and targeted energy metabolomics analysis indicated the upregulation of energy metabolism as the main action mechanism of MscL-G22S-activation on SCs. MscL-G22S-activated SCs showed significant upregulation of glycolysis and oxidative phosphorylation when SCs with stretching alone had only mild upregulation of energy metabolism than those without stimuli. MscL-G22S activation caused significant phosphorylation of the PI3K/AKT/mTOR signaling pathway and upregulation of HIF-1α/c-Myc. Inhibition of PI3K abolished the MscL-G22S activation-induced upregulation of HIF-1α/c-Myc signaling in SCs and reduced the levels of glycolysis- and oxidative phosphorylation-related substrates and mitochondrial activity. CONCLUSION Mechanical stretching activates MscL-G22S to significantly promote the energy metabolism of SCs and the production of energic substrates, which may be applied to enhance nerve regeneration via the glia-axonal metabolic coupling.
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Affiliation(s)
- Fangzhen Shan
- Medical Research Centre, Affiliated Hospital of Jining Medical University, Jining, Shandong Province, China
| | - Nannan Zhang
- Department of Respiratory and Critical Care, Affiliated Hospital of Jining Medical University, Jining, Shandong Province, China
| | - Xiaoying Yao
- Medical Research Centre, Affiliated Hospital of Jining Medical University, Jining, Shandong Province, China
| | - Yi Li
- Department of Neurology, Affiliated Hospital of Jining Medical University, 89 Guhuai Road, Jining City, Shandong Province, 272029, China
| | - Zihao Wang
- Cheeloo Medical College, Shandong University, Jinan, Shandong Province, China
| | - Chuanji Zhang
- College of Rehabilitation Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong Province, China
| | - Yuzhong Wang
- Medical Research Centre, Affiliated Hospital of Jining Medical University, Jining, Shandong Province, China.
- Department of Neurology, Affiliated Hospital of Jining Medical University, 89 Guhuai Road, Jining City, Shandong Province, 272029, China.
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Fan B, Chopp M, Zhang Y, Wang X, Kemper A, Zhang ZG, Liu XS. Ablation of Argonaute 2 in Schwann cells accelerates the progression of diabetic peripheral neuropathy. Glia 2023; 71:2196-2209. [PMID: 37178056 PMCID: PMC11057225 DOI: 10.1002/glia.24387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 04/25/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023]
Abstract
Schwann cells (SCs) form myelin and provide metabolic support for axons, and are essential for normal nerve function. Identification of key molecules specific to SCs and nerve fibers may provide new therapeutic targets for diabetic peripheral neuropathy (DPN). Argonaute2 (Ago2) is a key molecular player that mediates the activity of miRNA-guided mRNA cleavage and miRNA stability. Our study found that Ago2 knockout (Ago2-KO) in proteolipid protein (PLP) lineage SCs in mice resulted in a significant reduction of nerve conduction velocities and impairments of thermal and mechanical sensitivities. Histopathological data revealed that Ago2-KO significantly induced demyelination and neurodegeneration. When DPN was induced in both wild-type and Ago2-KO mice, Ago2-KO mice exhibited further decreased myelin thickness and exacerbated neurological outcomes compared with wild-type mice. Deep sequencing analysis of Ago2 immunoprecipitated complexes showed that deregulated miR-206 in Ago2-KO mice is highly related to mitochondrial function. In vitro data showed that knockdown of miR-200 induced mitochondrial dysfunction and apoptosis in SCs. Together, our data suggest that Ago2 in SCs is essential to maintain peripheral nerve function while ablation of Ago2 in SCs exacerbates SC dysfunction and neuronal degeneration in DPN. These findings provide new insight into the molecular mechanisms of DPN.
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Affiliation(s)
- Baoyan Fan
- Department of Neurology, Henry Ford Health System, Detroit, Michigan, USA
| | - Michael Chopp
- Department of Neurology, Henry Ford Health System, Detroit, Michigan, USA
- Department of Physics, Oakland University, Rochester, Michigan, USA
| | - Yi Zhang
- Department of Neurology, Henry Ford Health System, Detroit, Michigan, USA
| | - Xinli Wang
- Department of Neurology, Henry Ford Health System, Detroit, Michigan, USA
| | - Amy Kemper
- Department of Pathology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Zheng Gang Zhang
- Department of Neurology, Henry Ford Health System, Detroit, Michigan, USA
| | - Xian Shuang Liu
- Department of Neurology, Henry Ford Health System, Detroit, Michigan, USA
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Wu M, Li M, Liu W, Yan M, Li L, Ding W, Nian X, Dai W, Sun D, Zhu Y, Huang Q, Lu X, Cai Z, Hong F, Li X, Zhang L, Liu Z, Mo W, Zhang X, Zhang L. Nucleoporin Seh1 maintains Schwann cell homeostasis by regulating genome stability and necroptosis. Cell Rep 2023; 42:112802. [PMID: 37453065 DOI: 10.1016/j.celrep.2023.112802] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 06/06/2023] [Accepted: 06/26/2023] [Indexed: 07/18/2023] Open
Abstract
Schwann cells play critical roles in peripheral neuropathies; however, the regulatory mechanisms of their homeostasis remain largely unknown. Here, we show that nucleoporin Seh1, a component of nuclear pore complex, is important for Schwann cell homeostasis. Expression of Seh1 decreases as mice age. Loss of Seh1 leads to activated immune responses and cell necroptosis. Mice with depletion of Seh1 in Schwann cell lineage develop progressive reduction of Schwann cells in sciatic nerves, predominantly non-myelinating Schwann cells, followed by neural fiber degeneration and malfunction of the sensory and motor system. Mechanistically, Seh1 safeguards genome stability by mediating the interaction between SETDB1 and KAP1. The disrupted interaction after ablation of Seh1 derepresses endogenous retroviruses, which triggers ZBP1-dependent necroptosis in Schwann cells. Collectively, our results demonstrate that Seh1 is required for Schwann cell homeostasis by maintaining genome integrity and suggest that decrease of nucleoporins may participate in the pathogenesis of periphery neuropathies.
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Affiliation(s)
- Mei Wu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Man Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Wei Liu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Minbiao Yan
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Li Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Weichao Ding
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Ximing Nian
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Wenxiu Dai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Di Sun
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Yanqin Zhu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Qiuying Huang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Xiaoyun Lu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Zhiyu Cai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Fan Hong
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Xuewen Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Ling Zhang
- Department of Clinic Laboratory, the affiliated Chenggong Hospital, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Zhixiong Liu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Wei Mo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Xueqin Zhang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Liang Zhang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, China.
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Yang Z, Yu Z, Xiao B. Coordinated Regulation of Myelination by Growth Factor and Amino-acid Signaling Pathways. Neurosci Bull 2023; 39:453-465. [PMID: 36352321 PMCID: PMC10043148 DOI: 10.1007/s12264-022-00967-x] [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: 03/11/2022] [Accepted: 06/27/2022] [Indexed: 11/11/2022] Open
Abstract
Myelin-forming oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS) are essential for structural and functional homeostasis of nervous tissue. Albeit with certain similarities, the regulation of CNS and PNS myelination is executed differently. Recent advances highlight the coordinated regulation of oligodendrocyte myelination by amino-acid sensing and growth factor signaling pathways. In this review, we discuss novel insights into the understanding of differential regulation of oligodendrocyte and Schwann cell biology in CNS and PNS myelination, with particular focus on the roles of growth factor-stimulated RHEB-mTORC1 and GATOR2-mediated amino-acid sensing/signaling pathways. We also discuss recent progress on the metabolic regulation of oligodendrocytes and Schwann cells and the impact of their dysfunction on neuronal function and disease.
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Affiliation(s)
- Zhiwen Yang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518000, China
| | - Zongyan Yu
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518000, China.
| | - Bo Xiao
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518000, China.
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8
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Schwann cell functions in peripheral nerve development and repair. Neurobiol Dis 2023; 176:105952. [PMID: 36493976 DOI: 10.1016/j.nbd.2022.105952] [Citation(s) in RCA: 36] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/23/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
The glial cell of the peripheral nervous system (PNS), the Schwann cell (SC), counts among the most multifaceted cells of the body. During development, SCs secure neuronal survival and participate in axonal path finding. Simultaneously, they orchestrate the architectural set up of the developing nerves, including the blood vessels and the endo-, peri- and epineurial layers. Perinatally, in rodents, SCs radially sort and subsequently myelinate individual axons larger than 1 μm in diameter, while small calibre axons become organised in non-myelinating Remak bundles. SCs have a vital role in maintaining axonal health throughout life and several specialized SC types perform essential functions at specific locations, such as terminal SC at the neuromuscular junction (NMJ) or SC within cutaneous sensory end organs. In addition, neural crest derived satellite glia maintain a tight communication with the soma of sensory, sympathetic, and parasympathetic neurons and neural crest derivatives are furthermore an indispensable part of the enteric nervous system. The remarkable plasticity of SCs becomes evident in the context of a nerve injury, where SC transdifferentiate into intriguing repair cells, which orchestrate a regenerative response that promotes nerve repair. Indeed, the multiple adaptations of SCs are captivating, but remain often ill-resolved on the molecular level. Here, we summarize and discuss the knowns and unknowns of the vast array of functions that this single cell type can cover in peripheral nervous system development, maintenance, and repair.
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9
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Abd Razak NH, Zainey AS, Idris J, Daud MF. The Fundamentals of Schwann Cell Biology. INDUSTRIAL REVOLUTION IN KNOWLEDGE MANAGEMENT AND TECHNOLOGY 2023:105-113. [DOI: 10.1007/978-3-031-29265-1_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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10
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Cristobal CD, Lee HK. Development of myelinating glia: An overview. Glia 2022; 70:2237-2259. [PMID: 35785432 PMCID: PMC9561084 DOI: 10.1002/glia.24238] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/24/2022] [Accepted: 06/24/2022] [Indexed: 01/07/2023]
Abstract
Myelin is essential to nervous system function, playing roles in saltatory conduction and trophic support. Oligodendrocytes (OLs) and Schwann cells (SCs) form myelin in the central and peripheral nervous systems respectively and follow different developmental paths. OLs are neural stem-cell derived and follow an intrinsic developmental program resulting in a largely irreversible differentiation state. During embryonic development, OL precursor cells (OPCs) are produced in distinct waves originating from different locations in the central nervous system, with a subset developing into myelinating OLs. OPCs remain evenly distributed throughout life, providing a population of responsive, multifunctional cells with the capacity to remyelinate after injury. SCs derive from the neural crest, are highly dependent on extrinsic signals, and have plastic differentiation states. SC precursors (SCPs) are produced in early embryonic nerve structures and differentiate into multipotent immature SCs (iSCs), which initiate radial sorting and differentiate into myelinating and non-myelinating SCs. Differentiated SCs retain the capacity to radically change phenotypes in response to external signals, including becoming repair SCs, which drive peripheral regeneration. While several transcription factors and myelin components are common between OLs and SCs, their differentiation mechanisms are highly distinct, owing to their unique lineages and their respective environments. In addition, both OLs and SCs respond to neuronal activity and regulate nervous system output in reciprocal manners, possibly through different pathways. Here, we outline their basic developmental programs, mechanisms regulating their differentiation, and recent advances in the field.
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Affiliation(s)
- Carlo D. Cristobal
- Integrative Program in Molecular and Biomedical SciencesBaylor College of MedicineHoustonTexasUSA,Jan and Dan Duncan Neurological Research InstituteTexas Children's HospitalHoustonTexasUSA
| | - Hyun Kyoung Lee
- Integrative Program in Molecular and Biomedical SciencesBaylor College of MedicineHoustonTexasUSA,Jan and Dan Duncan Neurological Research InstituteTexas Children's HospitalHoustonTexasUSA,Department of PediatricsBaylor College of MedicineHoustonTexasUSA,Department of NeuroscienceBaylor College of MedicineHoustonTexasUSA
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11
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Corty MM, Hulegaard AL, Hill JQ, Sheehan AE, Aicher SA, Freeman MR. Discoidin domain receptor regulates ensheathment, survival and caliber of peripheral axons. Development 2022; 149:281293. [PMID: 36355066 PMCID: PMC10112903 DOI: 10.1242/dev.200636] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 10/27/2022] [Indexed: 11/12/2022]
Abstract
Most invertebrate axons and small-caliber axons in mammalian peripheral nerves are unmyelinated but still ensheathed by glia. Here, we use Drosophila wrapping glia to study the development and function of non-myelinating axon ensheathment, which is poorly understood. Selective ablation of these glia from peripheral nerves severely impaired larval locomotor behavior. In an in vivo RNA interference screen to identify glial genes required for axon ensheathment, we identified the conserved receptor tyrosine kinase Discoidin domain receptor (Ddr). In larval peripheral nerves, loss of Ddr resulted in severely reduced ensheathment of axons and reduced axon caliber, and we found a strong dominant genetic interaction between Ddr and the type XV/XVIII collagen Multiplexin (Mp), suggesting that Ddr functions as a collagen receptor to drive axon wrapping. In adult nerves, loss of Ddr decreased long-term survival of sensory neurons and significantly reduced axon caliber without overtly affecting ensheathment. Our data establish essential roles for non-myelinating glia in nerve development, maintenance and function, and identify Ddr as a key regulator of axon-glia interactions during ensheathment and establishment of axon caliber.
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Affiliation(s)
- Megan M Corty
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | | | - Jo Q Hill
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Amy E Sheehan
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Sue A Aicher
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Marc R Freeman
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
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12
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Davinelli S, Medoro A, Intrieri M, Saso L, Scapagnini G, Kang JX. Targeting NRF2-KEAP1 axis by Omega-3 fatty acids and their derivatives: Emerging opportunities against aging and diseases. Free Radic Biol Med 2022; 193:736-750. [PMID: 36402440 DOI: 10.1016/j.freeradbiomed.2022.11.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/01/2022] [Accepted: 11/10/2022] [Indexed: 11/18/2022]
Abstract
The transcription factor NRF2 and its endogenous inhibitor KEAP1 play a crucial role in the maintenance of cellular redox homeostasis by regulating the gene expression of diverse networks of antioxidant, anti-inflammatory, and detoxification enzymes. Therefore, activation of NRF2 provides cytoprotection against numerous pathologies, including age-related diseases. An age-associated loss of NRF2 function may be a key driving force behind the aging phenotype. Recently, numerous NRF2 inducers have been identified and some of them are promising candidates to restore NRF2 transcriptional activity during aging. Emerging evidence indicates that omega-3 (n-3) polyunsaturated fatty acids (PUFAs) and their electrophilic derivatives may trigger a protective response via NRF2 activation, rescuing or maintaining cellular redox homeostasis. In this review, we provide an overview of the NRF2-KEAP1 system and its dysregulation in aging cells. We also summarize current studies on the modulatory role of n-3 PUFAs as potential agents to prevent multiple chronic diseases and restore the age-related impairment of NRF2 function.
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Affiliation(s)
- Sergio Davinelli
- Department of Medicine and Health Sciences "V. Tiberio", University of Molise, Campobasso, Italy
| | - Alessandro Medoro
- Department of Medicine and Health Sciences "V. Tiberio", University of Molise, Campobasso, Italy
| | - Mariano Intrieri
- Department of Medicine and Health Sciences "V. Tiberio", University of Molise, Campobasso, Italy
| | - Luciano Saso
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Rome, Italy
| | - Giovanni Scapagnini
- Department of Medicine and Health Sciences "V. Tiberio", University of Molise, Campobasso, Italy.
| | - Jing X Kang
- Laboratory for Lipid Medicine and Technology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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13
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Reed CB, Feltri ML, Wilson ER. Peripheral glia diversity. J Anat 2022; 241:1219-1234. [PMID: 34131911 PMCID: PMC8671569 DOI: 10.1111/joa.13484] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/20/2021] [Accepted: 05/26/2021] [Indexed: 12/13/2022] Open
Abstract
Recent years have seen an evolving appreciation for the role of glial cells in the nervous system. As we move away from the typical neurocentric view of neuroscience, the complexity and variability of central nervous system glia is emerging, far beyond the three main subtypes: astrocytes, oligodendrocytes, and microglia. Yet the diversity of the glia found in the peripheral nervous system remains rarely discussed. In this review, we discuss the developmental origin, morphology, and function of the different populations of glia found in the peripheral nervous system, including: myelinating Schwann cells, Remak Schwann cells, repair Schwann cells, satellite glia, boundary cap-derived glia, perineurial glia, terminal Schwann cells, glia found in the skin, olfactory ensheathing cells, and enteric glia. The morphological and functional heterogeneity of glia found in the periphery reflects the diverse roles the nervous system performs throughout the body. Further, it highlights a complexity that should be appreciated and considered when it comes to a complete understanding of the peripheral nervous system in health and disease.
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Affiliation(s)
- Chelsey B Reed
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences State, University of New York at Buffalo, Buffalo, New York, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences State, University of New York at Buffalo, Buffalo, New York, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
| | - Emma R Wilson
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences State, University of New York at Buffalo, Buffalo, New York, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
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14
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Rumora AE, Kim B, Feldman EL. A Role for Fatty Acids in Peripheral Neuropathy Associated with Type 2 Diabetes and Prediabetes. Antioxid Redox Signal 2022; 37:560-577. [PMID: 35152728 PMCID: PMC9499450 DOI: 10.1089/ars.2021.0155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 01/19/2022] [Accepted: 01/25/2022] [Indexed: 11/12/2022]
Abstract
Significance: As the global prevalence of diabetes rises, diabetic complications are also increasing at an alarming rate. Peripheral neuropathy (PN) is the most prevalent complication of diabetes and prediabetes, and is characterized by progressive sensory loss resulting from nerve damage. While hyperglycemia is the major risk factor for PN in type 1 diabetes (T1D), the metabolic syndrome (MetS) underlies the onset and progression of PN in type 2 diabetes (T2D) and prediabetes. Recent Advances: Recent reports show that dyslipidemia, a MetS component, is strongly associated with PN in T2D and prediabetes. Dyslipidemia is characterized by an abnormal plasma lipid profile with uncontrolled lipid levels, and both clinical and preclinical studies implicate a role for dietary fatty acids (FAs) in PN pathogenesis. Molecular studies further show that saturated and unsaturated FAs differentially regulate the nerve lipid profile and nerve function. Critical Issues: We first review the properties of FAs and the neuroanatomy of the peripheral nervous system (PNS). Second, we discuss clinical and preclinical studies that implicate the involvement of FAs in PN. Third, we summarize the potential effects of FAs on nerve function and lipid metabolism within the peripheral nerves, sensory neurons, and Schwann cells. Future Directions: Future directions will focus on identifying molecular pathways in T2D and prediabetes that are modulated by FAs in PN. Determining pathophysiological mechanisms that underlie the injurious effects of saturated FAs and beneficial properties of unsaturated FAs will provide mechanistic targets for developing new targeted therapies to treat PN associated with T2D and prediabetes. Antioxid. Redox Signal. 37, 560-577.
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Affiliation(s)
- Amy E. Rumora
- Department of Neurology, Columbia University, New York, New York, USA
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Bhumsoo Kim
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Eva L. Feldman
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
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15
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Tricaud N, Gautier B, Berthelot J, Gonzalez S, Van Hameren G. Traumatic and Diabetic Schwann Cell Demyelination Is Triggered by a Transient Mitochondrial Calcium Release through Voltage Dependent Anion Channel 1. Biomedicines 2022; 10:biomedicines10061447. [PMID: 35740468 PMCID: PMC9220872 DOI: 10.3390/biomedicines10061447] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/07/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022] Open
Abstract
A large number of peripheral neuropathies, among which are traumatic and diabetic peripheral neuropathies, result from the degeneration of the myelin sheath, a process called demyelination. Demyelination does not result from Schwann cell death but from Schwann cell dedifferentiation, which includes reprograming and several catabolic and anabolic events. Starting around 4 h after nerve injury, activation of MAPK/cJun pathways is the earliest characterized step of this dedifferentiation program. Here we show, using real-time in vivo imaging, that Schwann cell mitochondrial pH, motility and calcium content are altered as soon as one hour after nerve injury. Mitochondrial calcium release occurred through the VDAC outer membrane channel and mPTP inner membrane channel. This calcium influx in the cytoplasm induced Schwann-cell demyelination via MAPK/c-Jun activation. Blocking calcium release through VDAC silencing or VDAC inhibitor TRO19622 prevented demyelination. We found that the kinetics of mitochondrial calcium release upon nerve injury were altered in the Schwann cells of diabetic mice suggesting a permanent leak of mitochondrial calcium in the cytoplasm. TRO19622 treatment alleviated peripheral nerve defects and motor deficit in diabetic mice. Together, these data indicate that mitochondrial calcium homeostasis is instrumental in the Schwann cell demyelination program and that blocking VDAC constitutes a molecular basis for developing anti-demyelinating drugs for diabetic peripheral neuropathy.
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Affiliation(s)
- Nicolas Tricaud
- Institut des Neurosciences de Montpellier, Univ. Montpellier, INSERM, 34000 Montpellier, France; (B.G.); (J.B.); (S.G.); (G.V.H.)
- I-Stem, UEVE/UPS U861, INSERM U861, AFM, 91100 Corbeil-Essonnes, France
- Correspondence:
| | - Benoit Gautier
- Institut des Neurosciences de Montpellier, Univ. Montpellier, INSERM, 34000 Montpellier, France; (B.G.); (J.B.); (S.G.); (G.V.H.)
| | - Jade Berthelot
- Institut des Neurosciences de Montpellier, Univ. Montpellier, INSERM, 34000 Montpellier, France; (B.G.); (J.B.); (S.G.); (G.V.H.)
| | - Sergio Gonzalez
- Institut des Neurosciences de Montpellier, Univ. Montpellier, INSERM, 34000 Montpellier, France; (B.G.); (J.B.); (S.G.); (G.V.H.)
| | - Gerben Van Hameren
- Institut des Neurosciences de Montpellier, Univ. Montpellier, INSERM, 34000 Montpellier, France; (B.G.); (J.B.); (S.G.); (G.V.H.)
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16
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Babetto E, Beirowski B. Of axons that struggle to make ends meet: Linking axonal bioenergetic failure to programmed axon degeneration. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148545. [PMID: 35339437 DOI: 10.1016/j.bbabio.2022.148545] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 03/07/2022] [Accepted: 03/16/2022] [Indexed: 02/07/2023]
Abstract
Axons are the long, fragile, and energy-hungry projections of neurons that are challenging to sustain. Together with their associated glia, they form the bulk of the neuronal network. Pathological axon degeneration (pAxD) is a driver of irreversible neurological disability in a host of neurodegenerative conditions. Halting pAxD is therefore an attractive therapeutic strategy. Here we review recent work demonstrating that pAxD is regulated by an auto-destruction program that revolves around axonal bioenergetics. We then focus on the emerging concept that axonal and glial energy metabolism are intertwined. We anticipate that these discoveries will encourage the pursuit of new treatment strategies for neurodegeneration.
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Affiliation(s)
- Elisabetta Babetto
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA; Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, USA.
| | - Bogdan Beirowski
- Institute for Myelin and Glia Exploration, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA; Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, USA.
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17
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Beirowski B. Emerging evidence for compromised axonal bioenergetics and axoglial metabolic coupling as drivers of neurodegeneration. Neurobiol Dis 2022; 170:105751. [PMID: 35569720 DOI: 10.1016/j.nbd.2022.105751] [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: 03/01/2022] [Revised: 04/20/2022] [Accepted: 05/09/2022] [Indexed: 10/18/2022] Open
Abstract
Impaired bioenergetic capacity of the nervous system is thought to contribute to the pathogenesis of many neurodegenerative diseases (NDD). Since neuronal synapses are believed to be the major energy consumers in the nervous system, synaptic derangements resulting from energy deficits have been suggested to play a central role for the development of many of these disorders. However, long axons constitute the largest compartment of the neuronal network, require large amounts of energy, are metabolically and structurally highly vulnerable, and undergo early injurious stresses in many NDD. These stresses likely impose additional energy demands for continuous adaptations and repair processes, and may eventually overwhelm axonal maintenance mechanisms. Indeed, pathological axon degeneration (pAxD) is now recognized as an etiological focus in a wide array of NDD associated with bioenergetic abnormalities. In this paper I first discuss the recognition that a simple experimental model for pAxD is regulated by an auto-destruction program that exhausts distressed axons energetically. Provision of the energy substrate pyruvate robustly counteracts this axonal breakdown. Importantly, energy decline in axons is not only a consequence but also an initiator of this program. This opens the intriguing possibility that axon dysfunction and pAxD can be suppressed by preemptively energizing distressed axons. Second, I focus on the emerging concept that axons communicate energetically with their flanking glia. This axoglial metabolic coupling can help offset the axonal energy decline that activates the pAxD program but also jeopardize axon integrity as a result of perturbed glial metabolism. Third, I present compelling evidence that abnormal axonal energetics and compromised axoglial metabolic coupling accompany the activation of the pAxD auto-destruction pathway in models of glaucoma, a widespread neurodegenerative condition with pathogenic overlap to other common NDD. In conclusion, I propose a novel conceptual framework suggesting that therapeutic interventions focused on bioenergetic support of the nervous system should also address axons and their metabolic interactions with glia.
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Affiliation(s)
- Bogdan Beirowski
- Institute for Myelin and Glia Exploration, New York State Center of Excellence in Bioinformatics & Life Sciences (CBLS), University at Buffalo, Buffalo, NY 14203, USA; Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, USA.
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18
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Shinouchi R, Shibata K, Jono S, Hasumi K, Nobe K. SMTP-44D Exerts Antioxidant and Anti-Inflammatory Effects through Its Soluble Epoxide Hydrolase Inhibitory Action in Immortalized Mouse Schwann Cells upon High Glucose Treatment. Int J Mol Sci 2022; 23:5187. [PMID: 35563575 PMCID: PMC9104197 DOI: 10.3390/ijms23095187] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/30/2022] [Accepted: 05/04/2022] [Indexed: 11/29/2022] Open
Abstract
Diabetic neuropathy (DN) is a major complication of diabetes mellitus. We have previously reported the efficacy of Stachybotrys microspora triprenyl phenol-44D (SMTP-44D) for DN through its potential antioxidant and anti-inflammatory activities. However, the mechanisms underlying the antioxidant and anti-inflammatory activities of SMTP-44D remain unclear. The present study aimed to explore the mechanism of these effects of SMTP-44D in regard to its inhibition of soluble epoxide hydrolase (sEH) in immortalized mouse Schwann cells (IMS32) following high glucose treatment. IMS32 cells were incubated in a high glucose medium for 48 h and then treated with SMTP-44D for 48 h. After incubation, the ratio of epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs), oxidative stress markers, such as NADPH oxidase-1 and malondialdehyde, inflammatory factors, such as the ratio of nuclear to cytosolic levels of NF-κB and the levels of IL-6, MCP-1, MMP-9, the receptor for the advanced glycation end product (RAGE), and apoptosis, were evaluated. SMTP-44D treatment considerably increased the ratio of EETs to DHETs and mitigated oxidative stress, inflammation, RAGE induction, and apoptosis after high glucose treatment. In conclusion, SMTP-44D can suppress the induction of apoptosis by exerting antioxidant and anti-inflammatory effects, possibly through sEH inhibition. SMTP-44D can be a potential therapeutic agent against DN.
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Affiliation(s)
- Ryosuke Shinouchi
- Division of Pharmacology, Department of Pharmacology, Toxicology & Therapeutics, School of Pharmacy, Pharmacology Research Center, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Keita Shibata
- Division of Pharmacology, Department of Pharmacology, Toxicology & Therapeutics, School of Pharmacy, Pharmacology Research Center, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Shiori Jono
- Division of Pharmacology, Department of Pharmacology, Toxicology & Therapeutics, School of Pharmacy, Pharmacology Research Center, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Keiji Hasumi
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwaicho, Fuchu-shi, Tokyo 183-8509, Japan
- Division of Research and Development, TMS Co., Ltd., 1-23-3-501 Miyamachi, Fuchu-shi, Tokyo 183-0023, Japan
| | - Koji Nobe
- Division of Pharmacology, Department of Pharmacology, Toxicology & Therapeutics, School of Pharmacy, Pharmacology Research Center, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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19
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Chandrasekaran K, Najimi N, Sagi AR, Yarlagadda S, Salimian M, Arvas MI, Hedayat AF, Kevas Y, Kadakia A, Russell JW. NAD + Precursors Repair Mitochondrial Function in Diabetes and Prevent Experimental Diabetic Neuropathy. Int J Mol Sci 2022; 23:4887. [PMID: 35563288 PMCID: PMC9102948 DOI: 10.3390/ijms23094887] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/18/2022] [Accepted: 04/26/2022] [Indexed: 12/04/2022] Open
Abstract
Axon degeneration in diabetic peripheral neuropathy (DPN) is associated with impaired NAD+ metabolism. We tested whether the administration of NAD+ precursors, nicotinamide mononucleotide (NMN) or nicotinamide riboside (NR), prevents DPN in models of Type 1 and Type 2 diabetes. NMN was administered to streptozotocin (STZ)-induced diabetic rats and STZ-induced diabetic mice by intraperitoneal injection at 50 or 100 mg/kg on alternate days for 2 months. mice The were fed with a high fat diet (HFD) for 2 months with or without added NR at 150 or 300 mg/kg for 2 months. The administration of NMN to STZ-induced diabetic rats or mice or dietary addition of NR to HFD-fed mice improved sensory function, normalized sciatic and tail nerve conduction velocities, and prevented loss of intraepidermal nerve fibers in skin samples from the hind-paw. In adult dorsal root ganglion (DRG) neurons isolated from HFD-fed mice, there was a decrease in NAD+ levels and mitochondrial maximum reserve capacity. These impairments were normalized in isolated DRG neurons from NR-treated mice. The results indicate that the correction of NAD+ depletion in DRG may be sufficient to prevent DPN but does not significantly affect glucose tolerance, insulin levels, or insulin resistance.
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Affiliation(s)
- Krish Chandrasekaran
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
- Veterans Affairs Medical Center, Baltimore, MD 21201, USA
| | - Neda Najimi
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Avinash R. Sagi
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Sushuma Yarlagadda
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Mohammad Salimian
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Muhammed Ikbal Arvas
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Ahmad F. Hedayat
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Yanni Kevas
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - Anand Kadakia
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
| | - James W. Russell
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.C.); (N.N.); (A.R.S.); (S.Y.); (M.S.); (M.I.A.); (A.F.H.); (Y.K.); (A.K.)
- Veterans Affairs Medical Center, Baltimore, MD 21201, USA
- CAMC Institute for Academic Medicine, 415 Morris Street Suite 300, Charleston, WV 25301, USA
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20
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Miranda M, Bonekamp NA, Kühl I. Starting the engine of the powerhouse: mitochondrial transcription and beyond. Biol Chem 2022; 403:779-805. [PMID: 35355496 DOI: 10.1515/hsz-2021-0416] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 03/09/2022] [Indexed: 12/25/2022]
Abstract
Mitochondria are central hubs for cellular metabolism, coordinating a variety of metabolic reactions crucial for human health. Mitochondria provide most of the cellular energy via their oxidative phosphorylation (OXPHOS) system, which requires the coordinated expression of genes encoded by both the nuclear (nDNA) and mitochondrial genomes (mtDNA). Transcription of mtDNA is not only essential for the biogenesis of the OXPHOS system, but also generates RNA primers necessary to initiate mtDNA replication. Like the prokaryotic system, mitochondria have no membrane-based compartmentalization to separate the different steps of mtDNA maintenance and expression and depend entirely on nDNA-encoded factors imported into the organelle. Our understanding of mitochondrial transcription in mammalian cells has largely progressed, but the mechanisms regulating mtDNA gene expression are still poorly understood despite their profound importance for human disease. Here, we review mechanisms of mitochondrial gene expression with a focus on the recent findings in the field of mammalian mtDNA transcription and disease phenotypes caused by defects in proteins involved in this process.
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Affiliation(s)
- Maria Miranda
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, D-50931, Germany
| | - Nina A Bonekamp
- Department of Neuroanatomy, Mannheim Center for Translational Neurosciences (MCTN), Medical Faculty Mannheim, Heidelberg University, Mannheim, D-68167, Germany
| | - Inge Kühl
- Department of Cell Biology, Institute of Integrative Biology of the Cell (I2BC), UMR9198, CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, F-91190, France
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21
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Gomez-Sanchez JA, Patel N, Martirena F, Fazal SV, Mutschler C, Cabedo H. Emerging Role of HDACs in Regeneration and Ageing in the Peripheral Nervous System: Repair Schwann Cells as Pivotal Targets. Int J Mol Sci 2022; 23:ijms23062996. [PMID: 35328416 PMCID: PMC8951080 DOI: 10.3390/ijms23062996] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/04/2022] [Accepted: 03/09/2022] [Indexed: 02/07/2023] Open
Abstract
The peripheral nervous system (PNS) has a remarkable regenerative capacity in comparison to the central nervous system (CNS), a phenomenon that is impaired during ageing. The ability of PNS axons to regenerate after injury is due to Schwann cells (SC) being reprogrammed into a repair phenotype called Repair Schwann cells. These repair SCs are crucial for supporting axonal growth after injury, myelin degradation in a process known as myelinophagy, neurotropic factor secretion, and axonal growth guidance through the formation of Büngner bands. After regeneration, repair SCs can remyelinate newly regenerated axons and support nonmyelinated axons. Increasing evidence points to an epigenetic component in the regulation of repair SC gene expression changes, which is necessary for SC reprogramming and regeneration. One of these epigenetic regulations is histone acetylation by histone acetyl transferases (HATs) or histone deacetylation by histone deacetylases (HDACs). In this review, we have focused particularly on three HDAC classes (I, II, and IV) that are Zn2+-dependent deacetylases. These HDACs are important in repair SC biology and remyelination after PNS injury. Another key aspect explored in this review is HDAC genetic compensation in SCs and novel HDAC inhibitors that are being studied to improve nerve regeneration.
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Affiliation(s)
- Jose A. Gomez-Sanchez
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández—Consejo Superior de Investigaciones Científicas, 03550 San Juan de Alicante, Spain; (N.P.); (H.C.)
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), 03010 Alicante, Spain
- Correspondence: ; Tel.: +34-965-919-594
| | - Nikiben Patel
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández—Consejo Superior de Investigaciones Científicas, 03550 San Juan de Alicante, Spain; (N.P.); (H.C.)
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), 03010 Alicante, Spain
| | - Fernanda Martirena
- Department of Hematology, General University Hospital of Elda, 03600 Elda, Spain;
| | - Shaline V. Fazal
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK; (S.V.F.); (C.M.)
- Wellcome—MRC Cambridge Stem Cell Institute, Puddicombe Way, Cambridge CB2 0AW, UK
| | - Clara Mutschler
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK; (S.V.F.); (C.M.)
| | - Hugo Cabedo
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández—Consejo Superior de Investigaciones Científicas, 03550 San Juan de Alicante, Spain; (N.P.); (H.C.)
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), 03010 Alicante, Spain
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22
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Negro S, Pirazzini M, Rigoni M. Models and methods to study Schwann cells. J Anat 2022; 241:1235-1258. [PMID: 34988978 PMCID: PMC9558160 DOI: 10.1111/joa.13606] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 12/22/2022] Open
Abstract
Schwann cells (SCs) are fundamental components of the peripheral nervous system (PNS) of all vertebrates and play essential roles in development, maintenance, function, and regeneration of peripheral nerves. There are distinct populations of SCs including: (1) myelinating SCs that ensheath axons by a specialized plasma membrane, called myelin, which enhances the conduction of electric impulses; (2) non‐myelinating SCs, including Remak SCs, which wrap bundles of multiple axons of small caliber, and perysinaptic SCs (PSCs), associated with motor axon terminals at the neuromuscular junction (NMJ). All types of SCs contribute to PNS regeneration through striking morphological and functional changes in response to nerve injury, are affected in peripheral neuropathies and show abnormalities and a diminished plasticity during aging. Therefore, methodological approaches to study and manipulate SCs in physiological and pathophysiological conditions are crucial to expand the present knowledge on SC biology and to devise new therapeutic strategies to counteract neurodegenerative conditions and age‐derived denervation. We present here an updated overview of traditional and emerging methodologies for the study of SCs for scientists approaching this research field.
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Affiliation(s)
- Samuele Negro
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padua, Padua, Italy.,CIR-Myo, Centro Interdipartimentale di Ricerca di Miologia, University of Padua, Padova, Italy
| | - Michela Rigoni
- Department of Biomedical Sciences, University of Padua, Padua, Italy.,CIR-Myo, Centro Interdipartimentale di Ricerca di Miologia, University of Padua, Padova, Italy
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23
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An Z, Zheng D, Wei D, Jiang D, Xing X, Liu C. Correlation between Acylcarnitine and Peripheral Neuropathy in Type 2 Diabetes Mellitus. J Diabetes Res 2022; 2022:8115173. [PMID: 35224109 PMCID: PMC8872664 DOI: 10.1155/2022/8115173] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 01/14/2022] [Accepted: 02/08/2022] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE In patients with type 2 diabetes mellitus (T2DM), it is unknown whether acylcarnitine changes in the patient's plasma as diabetic peripheral neuropathy (DPN) occurs. The purpose of the present study was to investigate the correlation between acylcarnitines and DPN in Chinese patients with T2DM. METHODS A total of 508 patients admitted to the First Affiliated Hospital of Jinzhou Medical University were included in this study, and all of whom were hospitalized for T2DM from January 2018 to December 2020. The diagnostic criteria for DPN were based on the 2017 Chinese Guidelines for the Prevention of Type 2 Diabetes. The contents of 25 acylcarnitine metabolites in fasting blood were determined by mass spectrometry. The measured acylcarnitines were classified by factor analysis, and the factors were extracted. To determine the correlation between acylcarnitines and DPN, binary logistic regression analysis was applied. RESULTS Among the 508 T2DM patients, 270 had DPN. Six factors were extracted from 25 acylcarnitines, and the cumulative contribution rate of variance was 61.02%. After the adjustment for other potential confounding factors, such as other carnitines and conventional risk factors, Factor 2 was positively associated with an increased risk of DPN (OR: 1.38, 95% CI: 1.13-1.69). Factor 2 contained acetylcarnitine (C2), propionylcarnitine (C3), butylcarnitine (C4), and isovalerylcarnitine (C5). CONCLUSIONS Plasma levels of short-chain acylcarnitines (C2, C3, C4, and C5) were positively associated with DPN risk.
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Affiliation(s)
- Zhenni An
- Department of Endocrinology, First Affiliated Hospital of Jinzhou Medical University, 121001, China
| | - Danmeng Zheng
- Department of Endocrinology, First Affiliated Hospital of Jinzhou Medical University, 121001, China
| | - Dongzhuo Wei
- Department of Clinical Discipline of Chinese and Western Integrative Medicine, Liaoning University of Traditional Chinese Medicine, 110847, China
| | - Dingwen Jiang
- Department of Endocrinology, First Affiliated Hospital of Jinzhou Medical University, 121001, China
| | - Xuejiao Xing
- Department of Endocrinology, First Affiliated Hospital of Jinzhou Medical University, 121001, China
| | - Chang Liu
- Department of Endocrinology, First Affiliated Hospital of Jinzhou Medical University, 121001, China
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24
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Sardella-Silva G, Mietto BS, Ribeiro-Resende VT. Four Seasons for Schwann Cell Biology, Revisiting Key Periods: Development, Homeostasis, Repair, and Aging. Biomolecules 2021; 11:1887. [PMID: 34944531 PMCID: PMC8699407 DOI: 10.3390/biom11121887] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 01/28/2023] Open
Abstract
Like the seasons of the year, all natural things happen in stages, going through adaptations when challenged, and Schwann cells are a great example of that. During maturation, these cells regulate several steps in peripheral nervous system development. The Spring of the cell means the rise and bloom through organized stages defined by time-dependent regulation of factors and microenvironmental influences. Once matured, the Summer of the cell begins: a high energy stage focused on maintaining adult homeostasis. The Schwann cell provides many neuron-glia communications resulting in the maintenance of synapses. In the peripheral nervous system, Schwann cells are pivotal after injuries, balancing degeneration and regeneration, similarly to when Autumn comes. Their ability to acquire a repair phenotype brings the potential to reconnect axons to targets and regain function. Finally, Schwann cells age, not only by growing old, but also by imposed environmental cues, like loss of function induced by pathologies. The Winter of the cell presents as reduced activity, especially regarding their role in repair; this reflects on the regenerative potential of older/less healthy individuals. This review gathers essential information about Schwann cells in different stages, summarizing important participation of this intriguing cell in many functions throughout its lifetime.
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Affiliation(s)
- Gabriela Sardella-Silva
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil;
- Núcleo Multidisciplinar de Pesquisa em Biologia (Numpex-Bio), Campus de Duque de Caxias Geraldo Guerra Cidade, Universidade Federal do Rio de Janeiro, Duque de Caxias 25255-030, RJ, Brazil
| | - Bruno Siqueira Mietto
- Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora 36036-900, MG, Brazil;
| | - Victor Túlio Ribeiro-Resende
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil;
- Núcleo Multidisciplinar de Pesquisa em Biologia (Numpex-Bio), Campus de Duque de Caxias Geraldo Guerra Cidade, Universidade Federal do Rio de Janeiro, Duque de Caxias 25255-030, RJ, Brazil
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25
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Fralish Z, Lotz EM, Chavez T, Khodabukus A, Bursac N. Neuromuscular Development and Disease: Learning From in vitro and in vivo Models. Front Cell Dev Biol 2021; 9:764732. [PMID: 34778273 PMCID: PMC8579029 DOI: 10.3389/fcell.2021.764732] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/06/2021] [Indexed: 01/02/2023] Open
Abstract
The neuromuscular junction (NMJ) is a specialized cholinergic synaptic interface between a motor neuron and a skeletal muscle fiber that translates presynaptic electrical impulses into motor function. NMJ formation and maintenance require tightly regulated signaling and cellular communication among motor neurons, myogenic cells, and Schwann cells. Neuromuscular diseases (NMDs) can result in loss of NMJ function and motor input leading to paralysis or even death. Although small animal models have been instrumental in advancing our understanding of the NMJ structure and function, the complexities of studying this multi-tissue system in vivo and poor clinical outcomes of candidate therapies developed in small animal models has driven the need for in vitro models of functional human NMJ to complement animal studies. In this review, we discuss prevailing models of NMDs and highlight the current progress and ongoing challenges in developing human iPSC-derived (hiPSC) 3D cell culture models of functional NMJs. We first review in vivo development of motor neurons, skeletal muscle, Schwann cells, and the NMJ alongside current methods for directing the differentiation of relevant cell types from hiPSCs. We further compare the efficacy of modeling NMDs in animals and human cell culture systems in the context of five NMDs: amyotrophic lateral sclerosis, myasthenia gravis, Duchenne muscular dystrophy, myotonic dystrophy, and Pompe disease. Finally, we discuss further work necessary for hiPSC-derived NMJ models to function as effective personalized NMD platforms.
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Affiliation(s)
- Zachary Fralish
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Ethan M Lotz
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Taylor Chavez
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Alastair Khodabukus
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Nenad Bursac
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
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26
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Jia L, Liao M, Mou A, Zheng Q, Yang W, Yu Z, Cui Y, Xia X, Qin Y, Chen M, Xiao B. Rheb-regulated mitochondrial pyruvate metabolism of Schwann cells linked to axon stability. Dev Cell 2021; 56:2980-2994.e6. [PMID: 34619097 DOI: 10.1016/j.devcel.2021.09.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 08/12/2021] [Accepted: 09/10/2021] [Indexed: 02/05/2023]
Abstract
The metabolic coupling of Schwann cells (SCs) and peripheral axons is poorly understood. Few molecules in SCs are known to regulate axon stability. Using SC-specific Rheb knockout mice, we demonstrate that Rheb-regulated mitochondrial pyruvate metabolism is critical for SC-mediated non-cell-autonomous regulation of peripheral axon stability. Rheb knockout suppresses pyruvate dehydrogenase (PDH) activity (independently of mTORC1) and shifts pyruvate metabolism toward lactate production in SCs. The increased lactate causes age-dependent peripheral axon degeneration, affecting peripheral nerve function. Lactate, as an energy substrate and a potential signaling molecule, enhanced neuronal mitochondrial metabolism and energy production of peripheral nerves. Albeit beneficial to injured peripheral axons in the short term, we show that persistently increased lactate metabolism of neurons enhances ROS production, eventually damaging mitochondria, neuroenergetics, and axon stability. This study highlights the complex roles of lactate metabolism to peripheral axons and the importance of lactate homeostasis in preserving peripheral nerves.
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Affiliation(s)
- Lanlan Jia
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Maoxing Liao
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Aidi Mou
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Quanzhen Zheng
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518005, People's Republic of China; Department of Biology, School of Life Sciences, Brain Research Center, Southern University of Science and Technology, Shenzhen 518000, People's Republic of China
| | - Wanchun Yang
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Zongyan Yu
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518005, People's Republic of China; Department of Biology, School of Life Sciences, Brain Research Center, Southern University of Science and Technology, Shenzhen 518000, People's Republic of China
| | - Yiyuan Cui
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Xiaoqiang Xia
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China; Department of Biology, School of Life Sciences, Brain Research Center, Southern University of Science and Technology, Shenzhen 518000, People's Republic of China
| | - Yue Qin
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Mina Chen
- Neuroscience & Metabolism Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Bo Xiao
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518005, People's Republic of China; Department of Biology, School of Life Sciences, Brain Research Center, Southern University of Science and Technology, Shenzhen 518000, People's Republic of China.
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27
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Mammel AE, Delgado KC, Chin AL, Condon AF, Hill JQ, Aicher SA, Wang Y, Fedorov LM, Robinson FL. Distinct roles for the Charcot-Marie-tooth disease-causing endosomal regulators Mtmr5 and Mtmr13 in axon radial sorting and Schwann cell myelination. Hum Mol Genet 2021; 31:1216-1229. [PMID: 34718573 DOI: 10.1093/hmg/ddab311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 09/29/2021] [Accepted: 10/19/2021] [Indexed: 11/12/2022] Open
Abstract
The form of Charcot-Marie-Tooth type 4B (CMT4B) disease caused by mutations in myotubularin-related 5 (MTMR5; also called SET Binding Factor 1; SBF1) shows a spectrum of axonal and demyelinating nerve phenotypes. This contrasts with the CMT4B subtypes caused by MTMR2 or MTMR13 (SBF2) mutations, which are characterized by myelin outfoldings and classic demyelination. Thus, it is unclear whether MTMR5 plays an analogous or distinct role from that of its homolog, MTMR13, in the peripheral nervous system (PNS). MTMR5 and MTMR13 are pseudophosphatases predicted to regulate endosomal trafficking by activating Rab GTPases and binding to the phosphoinositide 3-phosphatase MTMR2. In the mouse PNS, Mtmr2 was required to maintain wild type levels of Mtmr5 and Mtmr13, suggesting that these factors function in discrete protein complexes. Genetic elimination of both Mtmr5 and Mtmr13 in mice led to perinatal lethality, indicating that the two proteins have partially redundant functions during embryogenesis. Loss of Mtmr5 in mice did not cause CMT4B-like myelin outfoldings. However, adult Mtmr5-/- mouse nerves contained fewer myelinated axons than control nerves, likely as a result of axon radial sorting defects. Consistently, Mtmr5 levels were highest during axon radial sorting and fell sharply after postnatal day seven. Our findings suggest that Mtmr5 and Mtmr13 ensure proper axon radial sorting and Schwann cell myelination, respectively, perhaps through their direct interactions with Mtmr2. This study enhances our understanding of the non-redundant roles of the endosomal regulators MTMR5 and MTMR13 during normal peripheral nerve development and disease.
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Affiliation(s)
- Anna E Mammel
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.,Cell, Developmental & Cancer Biology Graduate Program, Oregon Health & Science University
| | - Katherine C Delgado
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Andrea L Chin
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Alec F Condon
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.,Neuroscience Graduate Program, Oregon Health & Science University
| | - Jo Q Hill
- Department of Physiology and Pharmacology, Oregon Health & Science University
| | - Sue A Aicher
- Department of Physiology and Pharmacology, Oregon Health & Science University
| | - Yingming Wang
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health & Science University
| | - Lev M Fedorov
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health & Science University
| | - Fred L Robinson
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.,Vollum Institute, Oregon Health & Science University
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28
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Follis RM, Tep C, Genaro-Mattos TC, Kim ML, Ryu JC, Morrison VE, Chan JR, Porter N, Carter BD, Yoon SO. Metabolic Control of Sensory Neuron Survival by the p75 Neurotrophin Receptor in Schwann Cells. J Neurosci 2021; 41:8710-8724. [PMID: 34507952 PMCID: PMC8528492 DOI: 10.1523/jneurosci.3243-20.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 08/28/2021] [Accepted: 08/30/2021] [Indexed: 11/21/2022] Open
Abstract
We report that the neurotrophin receptor p75 contributes to sensory neuron survival through the regulation of cholesterol metabolism in Schwann cells. Selective deletion of p75 in mouse Schwann cells of either sex resulted in a 30% loss of dorsal root ganglia (DRG) neurons and diminished thermal sensitivity. P75 regulates Schwann cell cholesterol biosynthesis in response to BDNF, forming a co-receptor complex with ErbB2 and activating ErbB2-mediated stimulation of sterol regulatory element binding protein 2 (SREBP2), a master regulator of cholesterol synthesis. Schwann cells lacking p75 exhibited decreased activation of SREBP2 and a reduction in 7-dehydrocholesterol (7-DHC) reductase (DHCR7) expression, resulting in accumulation of the neurotoxic intermediate, 7-dehyrocholesterol in the sciatic nerve. Restoration of DHCR7 in p75 null Schwann cells in mice significantly attenuated DRG neuron loss. Together, these results reveal a mechanism by which the disruption of lipid metabolism in glial cells negatively influences sensory neuron survival, which has implications for a wide range of peripheral neuropathies.SIGNIFICANCE STATEMENT Although expressed in Schwann cells, the role of p75 in myelination has remained unresolved in part because of its dual expression in sensory neurons that Schwann cells myelinate. When p75 was deleted selectively among Schwann cells, myelination was minimally affected, while sensory neuron survival was reduced by 30%. The phenotype is mainly due to dysregulation of cholesterol biosynthesis in p75-deficient Schwann cells, leading to an accumulation of neurotoxic cholesterol precursor, 7-dehydrocholesterol (7-DHC). Mechanism-wise, we discovered that in response to BDNF, p75 recruits and activates ErbB2 independently of ErbB3, thereby stimulating the master regulator, sterol regulatory element binding protein 2 (SREBP2). These results together highlight a novel role of p75 in Schwann cells in regulating DRG neuron survival by orchestrating proper cholesterol metabolism.
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Affiliation(s)
- Rose M Follis
- Department of Biochemistry, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Chhavy Tep
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
| | - Thiago C Genaro-Mattos
- Department of Chemistry, Vanderbilt University School of Arts and Sciences, Nashville, Tennessee 37232
| | - Mi Lyang Kim
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
| | - Jae Cheon Ryu
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
| | - Vivianne E Morrison
- Department of Biochemistry, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Jonah R Chan
- Department of Neurology, University of California San Francisco, San Francisco, California 94158
| | - Ned Porter
- Department of Chemistry, Vanderbilt University School of Arts and Sciences, Nashville, Tennessee 37232
| | - Bruce D Carter
- Department of Biochemistry, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Sung Ok Yoon
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
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29
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Previtali SC. Peripheral Nerve Development and the Pathogenesis of Peripheral Neuropathy: the Sorting Point. Neurotherapeutics 2021; 18:2156-2168. [PMID: 34244926 PMCID: PMC8804061 DOI: 10.1007/s13311-021-01080-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2021] [Indexed: 12/12/2022] Open
Abstract
Nerve development requires a coordinated sequence of events and steps to be accomplished for the generation of functional peripheral nerves to convey sensory and motor signals. Any abnormality during development may result in pathological structure and function of the nerve, which evolves in peripheral neuropathy. In this review, we will briefly describe different steps of nerve development while we will mostly focus on the molecular mechanisms involved in radial sorting of axons, one of these nerve developmental steps. We will summarize current knowledge of molecular pathways so far reported in radial sorting and their possible interactions. Finally, we will describe how disruption of these pathways may result in human neuropathies.
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Affiliation(s)
- Stefano C Previtali
- Neuromuscular Repair Unit, InSpe (Institute of Experimental Neurology) and Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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30
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Wong FC, Ye L, Demir IE, Kahlert C. Schwann cell-derived exosomes: Janus-faced mediators of regeneration and disease. Glia 2021; 70:20-34. [PMID: 34519370 DOI: 10.1002/glia.24087] [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: 04/30/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 12/20/2022]
Abstract
The phenotypic plasticity of Schwann cells (SCs) has contributed to the regenerative potential of the peripheral nervous system (PNS), but also pathological processes. This double-sided effect has led to an increasing attention to the role of extracellular vesicles (EVs) or exosomes in SCs to examine the intercellular communication between SCs and their surroundings. Here, we first describe the current knowledge of SC and EV biology, which forms the basis for the updates on advances in SC-derived exosomes research. We seek to explore in-depth the exosome-mediated molecular mechanisms involved in the regulation of SCs and their microenvironment. This review concludes with potential applications of SC-derived exosomes as delivery vehicles for therapeutics and biomarkers. The goal of this review is to emphasize the crucial role of SC-derived exosomes in the functional integration of the PNS, highlighting an emerging area in which there is much to explore and re-explore.
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Affiliation(s)
- Fang Cheng Wong
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Linhan Ye
- Department of Surgery, Klinikum rechts der Isar, Technical University of Munich, School of Medicine, Munich, Germany.,Germany German Cancer Consortium (DKTK), Partner Site, Munich, Germany.,CRC 1321 Modelling and Targeting Pancreatic Cancer, Munich, Germany
| | - Ihsan Ekin Demir
- Department of Surgery, Klinikum rechts der Isar, Technical University of Munich, School of Medicine, Munich, Germany.,Germany German Cancer Consortium (DKTK), Partner Site, Munich, Germany.,Department of General Surgery, HPB-Unit, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey.,CRC 1321 Modelling and Targeting Pancreatic Cancer, Munich, Germany.,Else Kröner Clinician Scientist Professor for "Translational Pancreatic Surgery
| | - Christoph Kahlert
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,National Center for Tumor Diseases (NCT/UCC), Dresden, Germany
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31
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Della-Flora Nunes G, Wilson ER, Hurley E, He B, O'Malley BW, Poitelon Y, Wrabetz L, Feltri ML. Activation of mTORC1 and c-Jun by Prohibitin1 loss in Schwann cells may link mitochondrial dysfunction to demyelination. eLife 2021; 10:e66278. [PMID: 34519641 PMCID: PMC8478418 DOI: 10.7554/elife.66278] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 09/13/2021] [Indexed: 12/26/2022] Open
Abstract
Schwann cell (SC) mitochondria are quickly emerging as an important regulator of myelin maintenance in the peripheral nervous system (PNS). However, the mechanisms underlying demyelination in the context of mitochondrial dysfunction in the PNS are incompletely understood. We recently showed that conditional ablation of the mitochondrial protein Prohibitin 1 (PHB1) in SCs causes a severe and fast progressing demyelinating peripheral neuropathy in mice, but the mechanism that causes failure of myelin maintenance remained unknown. Here, we report that mTORC1 and c-Jun are continuously activated in the absence of Phb1, likely as part of the SC response to mitochondrial damage. Moreover, we demonstrate that these pathways are involved in the demyelination process, and that inhibition of mTORC1 using rapamycin partially rescues the demyelinating pathology. Therefore, we propose that mTORC1 and c-Jun may play a critical role as executioners of demyelination in the context of perturbations to SC mitochondria.
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Affiliation(s)
- Gustavo Della-Flora Nunes
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
| | - Emma R Wilson
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
| | - Edward Hurley
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
| | - Bin He
- Immunobiology & Transplant Science Center and Department of Surgery, Houston Methodist HospitalHoustonUnited States
| | - Bert W O'Malley
- Department of Medicine and Molecular and Cellular Biology, Baylor College of MedicineHoustonUnited States
| | - Yannick Poitelon
- Department of Neuroscience and Experimental Therapeutics, Albany Medical CollegeAlbanyUnited States
| | - Lawrence Wrabetz
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at BuffaloBuffaloUnited States
| | - M Laura Feltri
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at BuffaloBuffaloUnited States
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32
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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: 16] [Impact Index Per Article: 5.3] [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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33
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Della-Flora Nunes G, Wilson ER, Marziali LN, Hurley E, Silvestri N, He B, O'Malley BW, Beirowski B, Poitelon Y, Wrabetz L, Feltri ML. Prohibitin 1 is essential to preserve mitochondria and myelin integrity in Schwann cells. Nat Commun 2021; 12:3285. [PMID: 34078899 PMCID: PMC8172551 DOI: 10.1038/s41467-021-23552-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 04/20/2021] [Indexed: 12/11/2022] Open
Abstract
In peripheral nerves, Schwann cells form myelin and provide trophic support to axons. We previously showed that the mitochondrial protein prohibitin 2 can localize to the axon-Schwann-cell interface and is required for developmental myelination. Whether the homologous protein prohibitin 1 has a similar role, and whether prohibitins also play important roles in Schwann cell mitochondria is unknown. Here, we show that deletion of prohibitin 1 in Schwann cells minimally perturbs development, but later triggers a severe demyelinating peripheral neuropathy. Moreover, mitochondria are heavily affected by ablation of prohibitin 1 and demyelination occurs preferentially in cells with apparent mitochondrial loss. Furthermore, in response to mitochondrial damage, Schwann cells trigger the integrated stress response, but, contrary to what was previously suggested, this response is not detrimental in this context. These results identify a role for prohibitin 1 in myelin integrity and advance our understanding about the Schwann cell response to mitochondrial damage.
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Affiliation(s)
- Gustavo Della-Flora Nunes
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Departments of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Emma R Wilson
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Departments of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Leandro N Marziali
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Departments of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Edward Hurley
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Nicholas Silvestri
- Departments of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Bin He
- Immunobiology & Transplant Science Center and Department of Surgery, Houston Methodist Hospital, Houston, TX, USA
| | - Bert W O'Malley
- Departments of Medicine and Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Bogdan Beirowski
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Departments of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Yannick Poitelon
- Albany Medical College, Dept of Neuroscience and Experimental Therapeutics, Albany, NY, USA
| | - Lawrence Wrabetz
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Departments of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Departments of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA.
- Departments of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA.
- Departments of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA.
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Rinwa P, Calvo-Enrique L, Zhang MD, Nyengaard JR, Karlsson P, Ernfors P. Demise of nociceptive Schwann cells causes nerve retraction and pain hyperalgesia. Pain 2021; 162:1816-1827. [PMID: 33979318 PMCID: PMC8120683 DOI: 10.1097/j.pain.0000000000002169] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/11/2020] [Accepted: 11/18/2020] [Indexed: 12/14/2022]
Abstract
ABSTRACT Recent findings indicate that nociceptive nerves are not "free", but similar to touch and pressure sensitive nerves, terminate in an end-organ in mice. This sensory structure consists of the nociceptive nerves and specialized nociceptive Schwann cells forming a mesh-like organ in subepidermis with pain transduction initiated at both these cellular constituents. The intimate relation of nociceptive nerves with nociceptive Schwann cells in mice raises the question whether defects in nociceptive Schwann cells can by itself contribute to pain hyperalgesia, nerve retraction, and peripheral neuropathy. We therefore examined the existence of nociceptive Schwann cells in human skin and their possible contribution to neuropathy and pain hyperalgesia in mouse models. Similar to mouse, human skin contains SOX10+/S100B+/AQP1+ Schwann cells in the subepidermal border that have extensive processes, which are intimately associated with nociceptive nerves projecting into epidermis. The ablation of nociceptive Schwann cells in mice resulted in nerve retraction and mechanical, cold, and heat hyperalgesia. Conversely, ablating the nociceptive nerves led to a retraction of epidermal Schwann cell processes, changes in nociceptive Schwann cell soma morphology, heat analgesia, and mechanical hyperalgesia. Our results provide evidence for a nociceptive sensory end-organ in the human skin and using animal models highlight the interdependence of the nerve and the nociceptive Schwann cell. Finally, we show that demise of nociceptive Schwann cells is sufficient to cause neuropathic-like pain in the mouse.
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Affiliation(s)
- Puneet Rinwa
- Department of Medical Biochemistry and Biophysics, Division of Molecular Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - Laura Calvo-Enrique
- Department of Medical Biochemistry and Biophysics, Division of Molecular Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - Ming-Dong Zhang
- Department of Medical Biochemistry and Biophysics, Division of Molecular Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - Jens Randel Nyengaard
- Department of Clinical Medicine—Core Centre for Molecular Morphology, Section for Stereology and Microscopy, Aarhus University, Aarhus, Denmark
- Centre for Stochastic Geometry and Advanced Bioimaging, Aarhus University Hospital, Aarhus, Denmark
| | - Páll Karlsson
- Department of Clinical Medicine—Core Centre for Molecular Morphology, Section for Stereology and Microscopy, Aarhus University, Aarhus, Denmark
- Danish Pain Research Center, Aarhus University, Aarhus, Denmark
| | - Patrik Ernfors
- Department of Medical Biochemistry and Biophysics, Division of Molecular Neurobiology, Karolinska Institutet, Stockholm, Sweden
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35
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Kobayashi M, Zochodne DW. Diabetic polyneuropathy: Bridging the translational gap. J Peripher Nerv Syst 2021; 25:66-75. [PMID: 32573914 DOI: 10.1111/jns.12392] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 12/22/2022]
Abstract
Clinical trials for diabetic polyneuropathy (DPN) have failed to identify therapeutic impacts that have arrested or reversed the disorder, despite a long history. This review considers DPN in the context of a unique neurodegenerative disorder that targets peripheral neurons and their companion glial cells. The approach is to examine what cells, cell substructures, and pathways are implicated in causing DPN and how they might be addressed therapeutically. These include axonopathy, neuronopathy, hyperglycemia, polyol flux, advanced glycation endproduct (AGE)-receptor AGE signaling, growth factor disruption, abnormal insulin signaling, and abnormalities of other intrinsic neuron pathways. Mitochondrial dysfunction and lipid toxicity are largely delegated to the companion review in this issue by Stino and Feldman. Finally, the linkage between axon plasticity of cutaneous nerves, peripheral neuroregenerative pathways, and diabetes are discussed.
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Affiliation(s)
- Masaki Kobayashi
- Department of Neurology, Nissan Tamagawa Hospital, Tokyo, Japan.,Department of Neurology and Neurological Science, Tokyo Medical and Dental University, Tokyo, Japan
| | - Douglas W Zochodne
- Division of Neurology and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
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36
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Spaas J, van Veggel L, Schepers M, Tiane A, van Horssen J, Wilson DM, Moya PR, Piccart E, Hellings N, Eijnde BO, Derave W, Schreiber R, Vanmierlo T. Oxidative stress and impaired oligodendrocyte precursor cell differentiation in neurological disorders. Cell Mol Life Sci 2021; 78:4615-4637. [PMID: 33751149 PMCID: PMC8195802 DOI: 10.1007/s00018-021-03802-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 02/12/2021] [Accepted: 02/24/2021] [Indexed: 02/07/2023]
Abstract
Oligodendrocyte precursor cells (OPCs) account for 5% of the resident parenchymal central nervous system glial cells. OPCs are not only a back-up for the loss of oligodendrocytes that occurs due to brain injury or inflammation-induced demyelination (remyelination) but are also pivotal in plastic processes such as learning and memory (adaptive myelination). OPC differentiation into mature myelinating oligodendrocytes is controlled by a complex transcriptional network and depends on high metabolic and mitochondrial demand. Mounting evidence shows that OPC dysfunction, culminating in the lack of OPC differentiation, mediates the progression of neurodegenerative disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. Importantly, neurodegeneration is characterised by oxidative and carbonyl stress, which may primarily affect OPC plasticity due to the high metabolic demand and a limited antioxidant capacity associated with this cell type. The underlying mechanisms of how oxidative/carbonyl stress disrupt OPC differentiation remain enigmatic and a focus of current research efforts. This review proposes a role for oxidative/carbonyl stress in interfering with the transcriptional and metabolic changes required for OPC differentiation. In particular, oligodendrocyte (epi)genetics, cellular defence and repair responses, mitochondrial signalling and respiration, and lipid metabolism represent key mechanisms how oxidative/carbonyl stress may hamper OPC differentiation in neurodegenerative disorders. Understanding how oxidative/carbonyl stress impacts OPC function may pave the way for future OPC-targeted treatment strategies in neurodegenerative disorders.
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Affiliation(s)
- Jan Spaas
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
- Department of Movement and Sports Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Lieve van Veggel
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
- Department Psychiatry and Neuropsychology, Division of Translational Neuroscience, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Melissa Schepers
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
- Department Psychiatry and Neuropsychology, Division of Translational Neuroscience, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Assia Tiane
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
- Department Psychiatry and Neuropsychology, Division of Translational Neuroscience, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Jack van Horssen
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
- Department of Molecular Cell Biology and Immunology, Amsterdam Neuroscience, MS Center Amsterdam, Amsterdam University Medical Center, Location VUmc, Amsterdam, The Netherlands
| | - David M Wilson
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
| | - Pablo R Moya
- Facultad de Ciencias, Instituto de Fisiología, Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Universidad de Valparaíso, Valparaíso, Chile
| | - Elisabeth Piccart
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
| | - Niels Hellings
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
| | - Bert O Eijnde
- University MS Center (UMSC), Hasselt-Pelt, Belgium
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium
- Faculty of Medicine and Life Sciences, SMRC-Sportsmedical Research Center, BIOMED Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Wim Derave
- Department of Movement and Sports Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Rudy Schreiber
- Department Psychiatry and Neuropsychology, Division of Translational Neuroscience, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Tim Vanmierlo
- University MS Center (UMSC), Hasselt-Pelt, Belgium.
- BIOMED Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium.
- Department Psychiatry and Neuropsychology, Division of Translational Neuroscience, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.
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Nazareth L, St John J, Murtaza M, Ekberg J. Phagocytosis by Peripheral Glia: Importance for Nervous System Functions and Implications in Injury and Disease. Front Cell Dev Biol 2021; 9:660259. [PMID: 33898462 PMCID: PMC8060502 DOI: 10.3389/fcell.2021.660259] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/17/2021] [Indexed: 12/30/2022] Open
Abstract
The central nervous system (CNS) has very limited capacity to regenerate after traumatic injury or disease. In contrast, the peripheral nervous system (PNS) has far greater capacity for regeneration. This difference can be partly attributed to variances in glial-mediated functions, such as axon guidance, structural support, secretion of growth factors and phagocytic activity. Due to their growth-promoting characteristic, transplantation of PNS glia has been trialed for neural repair. After peripheral nerve injuries, Schwann cells (SCs, the main PNS glia) phagocytose myelin debris and attract macrophages to the injury site to aid in debris clearance. One peripheral nerve, the olfactory nerve, is unique in that it continuously regenerates throughout life. The olfactory nerve glia, olfactory ensheathing cells (OECs), are the primary phagocytes within this nerve, continuously clearing axonal debris arising from the normal regeneration of the nerve and after injury. In contrast to SCs, OECs do not appear to attract macrophages. SCs and OECs also respond to and phagocytose bacteria, a function likely critical for tackling microbial invasion of the CNS via peripheral nerves. However, phagocytosis is not always effective; inflammation, aging and/or genetic factors may contribute to compromised phagocytic activity. Here, we highlight the diverse roles of SCs and OECs with the focus on their phagocytic activity under physiological and pathological conditions. We also explore why understanding the contribution of peripheral glia phagocytosis may provide us with translational strategies for achieving axonal regeneration of the injured nervous system and potentially for the treatment of certain neurological diseases.
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Affiliation(s)
- Lynn Nazareth
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia
| | - James St John
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Mariyam Murtaza
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Jenny Ekberg
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
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38
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Peng Y, Li J, Luo D, Zhang S, Li S, Wang D, Wang X, Zhang Z, Wang X, Sun C, Gao X, Hui Y, He R. Muscle atrophy induced by overexpression of ALAS2 is related to muscle mitochondrial dysfunction. Skelet Muscle 2021; 11:9. [PMID: 33785075 PMCID: PMC8008657 DOI: 10.1186/s13395-021-00263-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/02/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND ALAS2 (delta-aminolevulinate synthase 2) is one of the two isoenzymes catalyzing the synthesis of delta-aminolevulinic acid (ALA), which is the first precursor of heme synthesis. ALAS2-overexpressing transgenic mice (Tg mice) showed syndrome of porphyria, a series of diseases related to the heme anabolism deficiency. Tg mice showed an obvious decrease in muscle size. Muscle atrophy results from a decrease in protein synthesis and an increase in protein degradation, which ultimately leads to a decrease in myofiber size due to loss of contractile proteins, organelles, nuclei, and cytoplasm. METHODS The forelimb muscle grip strength of age-matched ALAS-2 transgenic mice (Tg mice) and wild-type mice (WT mice) were measured with an automated grip strength meter. The activities of serum LDH and CK-MB were measured by Modular DPP. The histology of skeletal muscle (quadriceps femoris and gastrocnemius) was observed by hematoxylin and eosin (HE) staining, immunohistochemistry, and transmission electron microscope. Real-time PCR was used to detect mtDNA content and UCP3 mRNA expression. Evans blue dye staining was used to detect the membrane damage of the muscle fiber. Single skeletal muscle fiber diameter was measured by single-fiber analyses. Muscle adenosine triphosphate (ATP) levels were detected by a luminometric assay with an ATP assay kit. RESULTS Compared with WT mice, the strength of forelimb muscle and mass of gastrocnemius were decreased in Tg mice. The activities of serum CK-MB and LDH, the number of central nuclei fibers, and Evans blue positive fibers were more than those in WT mice, while the diameter of single fibers was smaller, which were associated with suppressed expression levels of MHC, myoD1, dystrophin, atrogin1, and MuRF1. Re-expression of eMyHC was only showed in the quadriceps of Tg mice, but not in WT mice. Muscle mitochondria in Tg mice showed dysfunction with descented ATP production and mtDNA content, downregulated UCP3 mRNA expression, and swelling of mitochondria. CONCLUSION ALAS2 overexpressing-transgenic mice (Tg mice) showed muscle dystrophy, which was associated with decreased atrogin-1 and MuRF-1, and closely related to mitochondrial dysfunction.
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Affiliation(s)
- Yahui Peng
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Jihong Li
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Dixian Luo
- Institute of Translational Medicine, National and Local Joint Engineering Laboratory of High-through Molecular Diagnostic Technology, the First People's Hospital of Chenzhou, The First Affiliated Hospital of Xiangnan University, Chenzhou, 423000, China
| | - Shuai Zhang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Sijia Li
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Dayong Wang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Xidi Wang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Zhujun Zhang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Xue Wang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Changhui Sun
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Xu Gao
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China.,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China.,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China
| | - Yang Hui
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, 150086, China. .,Heilongjiang Academy of Medical Sciences, Harbin, 150086, China. .,Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China (Harbin Medical University), Ministry of Education, Beijing, 150086, China.
| | - Rongzhang He
- Institute of Translational Medicine, National and Local Joint Engineering Laboratory of High-through Molecular Diagnostic Technology, the First People's Hospital of Chenzhou, The First Affiliated Hospital of Xiangnan University, Chenzhou, 423000, China. .,Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410078, China.
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Abstract
Neuropathy is a common complication of long-term diabetes that impairs quality of life by producing pain, sensory loss and limb amputation. The presence of neuropathy in both insulin-deficient (type 1) and insulin resistant (type 2) diabetes along with the slowing of progression of neuropathy by improved glycemic control in type 1 diabetes has caused the majority of preclinical and clinical investigations to focus on hyperglycemia as the initiating pathogenic lesion. Studies in animal models of diabetes have identified multiple plausible mechanisms of glucotoxicity to the nervous system including post-translational modification of proteins by glucose and increased glucose metabolism by aldose reductase, glycolysis and other catabolic pathways. However, it is becoming increasingly apparent that factors not necessarily downstream of hyperglycemia can also contribute to the incidence, progression and severity of neuropathy and neuropathic pain. For example, peripheral nerve contains insulin receptors that transduce the neurotrophic and neurosupportive properties of insulin, independent of systemic glucose regulation, while the detection of neuropathy and neuropathic pain in patients with metabolic syndrome and failure of improved glycemic control to protect against neuropathy in cohorts of type 2 diabetic patients has placed a focus on the pathogenic role of dyslipidemia. This review provides an overview of current understanding of potential initiating lesions for diabetic neuropathy and the multiple downstream mechanisms identified in cell and animal models of diabetes that may contribute to the pathogenesis of diabetic neuropathy and neuropathic pain.
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40
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Moss KR, Bopp TS, Johnson AE, Höke A. New evidence for secondary axonal degeneration in demyelinating neuropathies. Neurosci Lett 2021; 744:135595. [PMID: 33359733 PMCID: PMC7852893 DOI: 10.1016/j.neulet.2020.135595] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 10/31/2020] [Accepted: 12/19/2020] [Indexed: 12/28/2022]
Abstract
Development of peripheral nervous system (PNS) myelin involves a coordinated series of events between growing axons and the Schwann cell (SC) progenitors that will eventually ensheath them. Myelin sheaths have evolved out of necessity to maintain rapid impulse propagation while accounting for body space constraints. However, myelinating SCs perform additional critical functions that are required to preserve axonal integrity including mitigating energy consumption by establishing the nodal architecture, regulating axon caliber by organizing axonal cytoskeleton networks, providing trophic and potentially metabolic support, possibly supplying genetic translation materials and protecting axons from toxic insults. The intermediate steps between the loss of these functions and the initiation of axon degeneration are unknown but the importance of these processes provides insightful clues. Prevalent demyelinating diseases of the PNS include the inherited neuropathies Charcot-Marie-Tooth Disease, Type 1 (CMT1) and Hereditary Neuropathy with Liability to Pressure Palsies (HNPP) and the inflammatory diseases Acute Inflammatory Demyelinating Polyneuropathy (AIDP) and Chronic Inflammatory Demyelinating Polyneuropathy (CIDP). Secondary axon degeneration is a common feature of demyelinating neuropathies and this process is often correlated with clinical deficits and long-lasting disability in patients. There is abundant electrophysiological and histological evidence for secondary axon degeneration in patients and rodent models of PNS demyelinating diseases. Fully understanding the involvement of secondary axon degeneration in these diseases is essential for expanding our knowledge of disease pathogenesis and prognosis, which will be essential for developing novel therapeutic strategies.
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Affiliation(s)
- Kathryn R Moss
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Taylor S Bopp
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Anna E Johnson
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Ahmet Höke
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, MD, United States.
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41
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Small-molecule inhibitors of human mitochondrial DNA transcription. Nature 2020; 588:712-716. [PMID: 33328633 DOI: 10.1038/s41586-020-03048-z] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 10/22/2020] [Indexed: 01/31/2023]
Abstract
Altered expression of mitochondrial DNA (mtDNA) occurs in ageing and a range of human pathologies (for example, inborn errors of metabolism, neurodegeneration and cancer). Here we describe first-in-class specific inhibitors of mitochondrial transcription (IMTs) that target the human mitochondrial RNA polymerase (POLRMT), which is essential for biogenesis of the oxidative phosphorylation (OXPHOS) system1-6. The IMTs efficiently impair mtDNA transcription in a reconstituted recombinant system and cause a dose-dependent inhibition of mtDNA expression and OXPHOS in cell lines. To verify the cellular target, we performed exome sequencing of mutagenized cells and identified a cluster of amino acid substitutions in POLRMT that cause resistance to IMTs. We obtained a cryo-electron microscopy (cryo-EM) structure of POLRMT bound to an IMT, which further defined the allosteric binding site near the active centre cleft of POLRMT. The growth of cancer cells and the persistence of therapy-resistant cancer stem cells has previously been reported to depend on OXPHOS7-17, and we therefore investigated whether IMTs have anti-tumour effects. Four weeks of oral treatment with an IMT is well-tolerated in mice and does not cause OXPHOS dysfunction or toxicity in normal tissues, despite inducing a strong anti-tumour response in xenografts of human cancer cells. In summary, IMTs provide a potent and specific chemical biology tool to study the role of mtDNA expression in physiology and disease.
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Bonekamp NA, Peter B, Hillen HS, Felser A, Bergbrede T, Choidas A, Horn M, Unger A, Di Lucrezia R, Atanassov I, Li X, Koch U, Menninger S, Boros J, Habenberger P, Giavalisco P, Cramer P, Denzel MS, Nussbaumer P, Klebl B, Falkenberg M, Gustafsson CM, Larsson NG. Small-molecule inhibitors of human mitochondrial DNA transcription. Nature 2020. [PMID: 33328633 DOI: 10.1038/s41586-020-03048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
Altered expression of mitochondrial DNA (mtDNA) occurs in ageing and a range of human pathologies (for example, inborn errors of metabolism, neurodegeneration and cancer). Here we describe first-in-class specific inhibitors of mitochondrial transcription (IMTs) that target the human mitochondrial RNA polymerase (POLRMT), which is essential for biogenesis of the oxidative phosphorylation (OXPHOS) system1-6. The IMTs efficiently impair mtDNA transcription in a reconstituted recombinant system and cause a dose-dependent inhibition of mtDNA expression and OXPHOS in cell lines. To verify the cellular target, we performed exome sequencing of mutagenized cells and identified a cluster of amino acid substitutions in POLRMT that cause resistance to IMTs. We obtained a cryo-electron microscopy (cryo-EM) structure of POLRMT bound to an IMT, which further defined the allosteric binding site near the active centre cleft of POLRMT. The growth of cancer cells and the persistence of therapy-resistant cancer stem cells has previously been reported to depend on OXPHOS7-17, and we therefore investigated whether IMTs have anti-tumour effects. Four weeks of oral treatment with an IMT is well-tolerated in mice and does not cause OXPHOS dysfunction or toxicity in normal tissues, despite inducing a strong anti-tumour response in xenografts of human cancer cells. In summary, IMTs provide a potent and specific chemical biology tool to study the role of mtDNA expression in physiology and disease.
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Affiliation(s)
- Nina A Bonekamp
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Bradley Peter
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Hauke S Hillen
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Andrea Felser
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Moritz Horn
- Metabolic and Genetic Regulation of Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
- Acus Laboratories, Cologne, Germany
- JLP Health, Vienna, Austria
| | - Anke Unger
- Lead Discovery Center, Dortmund, Germany
| | | | - Ilian Atanassov
- Proteomics Core Facility, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Xinping Li
- Proteomics Core Facility, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Uwe Koch
- Lead Discovery Center, Dortmund, Germany
| | | | | | | | - Patrick Giavalisco
- Metabolomics Core Facility, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Martin S Denzel
- Metabolic and Genetic Regulation of Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | | | - Bert Klebl
- Lead Discovery Center, Dortmund, Germany
| | - Maria Falkenberg
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Claes M Gustafsson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden.
| | - Nils-Göran Larsson
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany.
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
- Max Planck Institute for Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.
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43
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Palavicini JP, Chen J, Wang C, Wang J, Qin C, Baeuerle E, Wang X, Woo JA, Kang DE, Musi N, Dupree JL, Han X. Early disruption of nerve mitochondrial and myelin lipid homeostasis in obesity-induced diabetes. JCI Insight 2020; 5:137286. [PMID: 33148881 PMCID: PMC7710310 DOI: 10.1172/jci.insight.137286] [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: 02/17/2020] [Accepted: 09/30/2020] [Indexed: 12/17/2022] Open
Abstract
Diabetic neuropathy is a major complication of diabetes. Current treatment options alleviate pain but do not stop the progression of the disease. At present, there are no approved disease-modifying therapies. Thus, developing more effective therapies remains a major unmet medical need. Seeking to better understand the molecular mechanisms driving peripheral neuropathy, as well as other neurological complications associated with diabetes, we performed spatiotemporal lipidomics, biochemical, ultrastructural, and physiological studies on PNS and CNS tissue from multiple diabetic preclinical models. We unraveled potentially novel molecular fingerprints underlying nerve damage in obesity-induced diabetes, including an early loss of nerve mitochondrial (cardiolipin) and myelin signature (galactosylceramide, sulfatide, and plasmalogen phosphatidylethanolamine) lipids that preceded mitochondrial, myelin, and axonal structural/functional defects; started in the PNS; and progressed to the CNS at advanced diabetic stages. Mechanistically, we provided substantial evidence indicating that these nerve mitochondrial/myelin lipid abnormalities are (surprisingly) not driven by hyperglycemia, dysinsulinemia, or insulin resistance, but rather associate with obesity/hyperlipidemia. Importantly, our findings have major clinical implications as they open the door to novel lipid-based biomarkers to diagnose and distinguish different subtypes of diabetic neuropathy (obese vs. nonobese diabetics), as well as to lipid-lowering therapeutic strategies for treatment of obesity/diabetes-associated neurological complications and for glycemic control.
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Affiliation(s)
- Juan P. Palavicini
- Barshop Institute for Longevity and Aging Studies and
- Division of Diabetes, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Juan Chen
- Barshop Institute for Longevity and Aging Studies and
- School of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Chunyan Wang
- Barshop Institute for Longevity and Aging Studies and
| | - Jianing Wang
- Barshop Institute for Longevity and Aging Studies and
| | - Chao Qin
- Barshop Institute for Longevity and Aging Studies and
| | - Eric Baeuerle
- Barshop Institute for Longevity and Aging Studies and
| | - Xinming Wang
- Byrd Alzheimer’s Center and Research Institute, USF Health Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Jung A. Woo
- Byrd Alzheimer’s Center and Research Institute, USF Health Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - David E. Kang
- Byrd Alzheimer’s Center and Research Institute, USF Health Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Nicolas Musi
- Barshop Institute for Longevity and Aging Studies and
- Division of Diabetes, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Jeffrey L. Dupree
- Department of Anatomy and Neurobiology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
- Research Service, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, Virginia, USA
| | - Xianlin Han
- Barshop Institute for Longevity and Aging Studies and
- Division of Diabetes, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
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44
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Bouçanova F, Chrast R. Metabolic Interaction Between Schwann Cells and Axons Under Physiological and Disease Conditions. Front Cell Neurosci 2020; 14:148. [PMID: 32547370 PMCID: PMC7274022 DOI: 10.3389/fncel.2020.00148] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 05/04/2020] [Indexed: 12/24/2022] Open
Abstract
Recent research into axon-glial interactions in the nervous system has made a compelling case that glial cells have a relevant role in the metabolic support of axons, and that, in the case of myelinating cells, this role is independent of myelination itself. In this mini-review article, we summarize some of those observations and focus on Schwann cells (SC), drawing parallels between glia of the central and peripheral nervous systems (PNS), pointing out limitations in current knowledge, and discussing its potential clinical relevance. First, we introduce SC, their development and main roles, and follow with an evolutionary perspective of glial metabolic function. Then we provide evidence of the myelin-independent aspects of axonal support and their coupling to neuronal metabolism. Finally, we address the opportunity to use SC-axon metabolic interactions as therapeutic targets to treat peripheral neuropathies.
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Affiliation(s)
- Filipa Bouçanova
- Department of Neuroscience, KarolinskaInstitutet, Stockholm, Sweden.,Department of Clinical Neuroscience, KarolinskaInstitutet, Stockholm, Sweden
| | - Roman Chrast
- Department of Neuroscience, KarolinskaInstitutet, Stockholm, Sweden.,Department of Clinical Neuroscience, KarolinskaInstitutet, Stockholm, Sweden
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45
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Horie M, Yoshioka N, Kusumi S, Sano H, Kurose M, Watanabe‐Iida I, Hossain I, Chiken S, Abe M, Yamamura K, Sakimura K, Nambu A, Shibata M, Takebayashi H. Disruption of
dystonin
in Schwann cells results in late‐onset neuropathy and sensory ataxia. Glia 2020; 68:2330-2344. [DOI: 10.1002/glia.23843] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/26/2020] [Accepted: 04/28/2020] [Indexed: 01/26/2023]
Affiliation(s)
- Masao Horie
- Division of Neurobiology and AnatomyGraduate School of Medical and Dental Sciences, Niigata University Niigata Japan
- Department of Morphological SciencesKagoshima University Kagoshima Japan
- Department of NursingNiigata College of Nursing Niigata Japan
| | - Nozomu Yoshioka
- Division of Neurobiology and AnatomyGraduate School of Medical and Dental Sciences, Niigata University Niigata Japan
| | - Satoshi Kusumi
- Department of Morphological SciencesKagoshima University Kagoshima Japan
| | - Hiromi Sano
- Division of System NeurophysiologyNational Institute for Physiological Sciences Okazaki Japan
- Department of Physiological SciencesSOKENDAI Okazaki Japan
| | - Masayuki Kurose
- Division of Oral PhysiologyGraduate School of Medical and Dental Sciences, Niigata University Niigata Japan
- Department of Physiology, School of Dentistry, Iwate Medical University Morioka Japan
| | - Izumi Watanabe‐Iida
- Department of Cellular NeurobiologyBrain Research Institute, Niigata University Niigata Japan
- Division of Oral Biochemistry, Graduate School of Medical and Dental Sciences, Niigata University Niigata Japan
| | - Ibrahim Hossain
- Division of Neurobiology and AnatomyGraduate School of Medical and Dental Sciences, Niigata University Niigata Japan
- Department of Biochemistry and Molecular BiologyJahangirnagar University Savar Dhaka Bangladesh
| | - Satomi Chiken
- Division of System NeurophysiologyNational Institute for Physiological Sciences Okazaki Japan
- Department of Physiological SciencesSOKENDAI Okazaki Japan
| | - Manabu Abe
- Department of Cellular NeurobiologyBrain Research Institute, Niigata University Niigata Japan
- Department of Animal Model DevelopmentBrain Research Institute, Niigata University Niigata Japan
| | - Kensuke Yamamura
- Division of Oral PhysiologyGraduate School of Medical and Dental Sciences, Niigata University Niigata Japan
| | - Kenji Sakimura
- Department of Cellular NeurobiologyBrain Research Institute, Niigata University Niigata Japan
- Department of Animal Model DevelopmentBrain Research Institute, Niigata University Niigata Japan
| | - Atsushi Nambu
- Division of System NeurophysiologyNational Institute for Physiological Sciences Okazaki Japan
- Department of Physiological SciencesSOKENDAI Okazaki Japan
| | - Masahiro Shibata
- Department of Morphological SciencesKagoshima University Kagoshima Japan
| | - Hirohide Takebayashi
- Division of Neurobiology and AnatomyGraduate School of Medical and Dental Sciences, Niigata University Niigata Japan
- Center for Coordination of Research FacilitiesNiigata University Niigata Japan
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46
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Wilson ER, Della-Flora Nunes G, Weaver MR, Frick LR, Feltri ML. Schwann cell interactions during the development of the peripheral nervous system. Dev Neurobiol 2020; 81:464-489. [PMID: 32281247 DOI: 10.1002/dneu.22744] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/14/2020] [Accepted: 04/06/2020] [Indexed: 12/21/2022]
Abstract
Schwann cells play a critical role in the development of the peripheral nervous system (PNS), establishing important relationships both with the extracellular milieu and other cell types, particularly neurons. In this review, we discuss various Schwann cell interactions integral to the proper establishment, spatial arrangement, and function of the PNS. We include signals that cascade onto Schwann cells from axons and from the extracellular matrix, bidirectional signals that help to establish the axo-glial relationship and how Schwann cells in turn support the axon. Further, we speculate on how Schwann cell interactions with other components of the developing PNS ultimately promote the complete construction of the peripheral nerve.
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Affiliation(s)
- Emma R Wilson
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Gustavo Della-Flora Nunes
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Michael R Weaver
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Luciana R Frick
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
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47
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Poitelon Y, Kopec AM, Belin S. Myelin Fat Facts: An Overview of Lipids and Fatty Acid Metabolism. Cells 2020; 9:cells9040812. [PMID: 32230947 PMCID: PMC7226731 DOI: 10.3390/cells9040812] [Citation(s) in RCA: 148] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 12/11/2022] Open
Abstract
Myelin is critical for the proper function of the nervous system and one of the most complex cell–cell interactions of the body. Myelination allows for the rapid conduction of action potentials along axonal fibers and provides physical and trophic support to neurons. Myelin contains a high content of lipids, and the formation of the myelin sheath requires high levels of fatty acid and lipid synthesis, together with uptake of extracellular fatty acids. Recent studies have further advanced our understanding of the metabolism and functions of myelin fatty acids and lipids. In this review, we present an overview of the basic biology of myelin lipids and recent insights on the regulation of fatty acid metabolism and functions in myelinating cells. In addition, this review may serve to provide a foundation for future research characterizing the role of fatty acids and lipids in myelin biology and metabolic disorders affecting the central and peripheral nervous system.
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48
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Beirowski B. Measuring Bioenergetic Signatures of Peripheral Nerve Segments by Extracellular Flux Analysis. Methods Mol Biol 2020; 2143:191-203. [PMID: 32524482 DOI: 10.1007/978-1-0716-0585-1_15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Changes of energy metabolism in axons and their adjacent glia as well as alterations in metabolic axon-glia cross talk are emerging as central mechanistic components underlying axon degeneration. The analysis of extracellular flux with commercial metabolic analyzers greatly facilitates the measurement of key parameters of glycolytic and mitochondrial energy metabolism in cells and tissues. In this chapter, I describe a straightforward method to capture bioenergetic profiles of acutely isolated peripheral nerve segments using the Agilent Seahorse XFe24 platform.
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Affiliation(s)
- Bogdan Beirowski
- Hunter James Kelly Research Institute, New York State Center of Excellence in Bioinformatics & Life Sciences (CBLS) RM B4-314, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA. .,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA.
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49
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Hackett AR, Strickland A, Milbrandt J. Disrupting insulin signaling in Schwann cells impairs myelination and induces a sensory neuropathy. Glia 2019; 68:963-978. [PMID: 31758725 DOI: 10.1002/glia.23755] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 10/28/2019] [Accepted: 11/05/2019] [Indexed: 12/14/2022]
Abstract
Although diabetic mice have been studied for decades, little is known about the cell type specific contributions to diabetic neuropathy (DN). Schwann cells (SCs) myelinate and provide trophic support to peripheral nervous system axons. Altered SC metabolism leads to myelin defects, which can be seen both in inherited and DNs. How SC metabolism is altered in DN is not fully understood, but it is clear that insulin resistance underlies impaired lipid metabolism in many cell types throughout the body via the phosphoinositide 3-kinase/protein kinase b (PKB)/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. Here, we created an insulin resistant SC by deleting both insulin receptor (INSR) and insulin-like growth factor receptor 1 (IGF1R), to determine the role of this signaling pathway in development and response to injury in order to understand SC defects in DN. We found that myelin is thinner throughout development and adulthood in INSR/IGF1R Schwann cell specific knock out mice. The nerves of these mutant mice had reduced expression of key genes that mediate fatty acid and cholesterol synthesis due to reduced mTOR-sterol regulatory element-binding protein signaling. In adulthood, these mice show sensory neuropathy phenotypes reminiscent of diabetic mice. Altogether, these data suggest that SCs may play an important role in DN and targeting their metabolism could lead to new therapies for DN.
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Affiliation(s)
- Amber R Hackett
- Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri
| | - Amy Strickland
- Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri
| | - Jeffrey Milbrandt
- Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri
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50
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Stierli S, Imperatore V, Lloyd AC. Schwann cell plasticity-roles in tissue homeostasis, regeneration, and disease. Glia 2019; 67:2203-2215. [PMID: 31215712 DOI: 10.1002/glia.23643] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 12/12/2022]
Abstract
How tissues are maintained over a lifetime and repaired following injury are fundamental questions in biology with a disruption to these processes underlying pathologies such as cancer and degenerative disorders. It is becoming increasingly clear that each tissue has a distinct mechanism to maintain homeostasis and respond to injury utilizing different types of stem/progenitor cell populations depending on the insult and/or with a contribution from more differentiated cells that are able to dedifferentiate to aid tissue regeneration. Peripheral nerves are highly quiescent yet show remarkable regenerative capabilities. Remarkably, there is no evidence for a classical stem cell population, rather all cell-types within the nerve are able to proliferate to produce new nerve tissue. Co-ordinating the regeneration of this tissue are Schwann cells (SCs), the main glial cells of the peripheral nervous system. SCs exist in architecturally stable structures that can persist for the lifetime of an animal, however, they are not postmitotic, in that following injury they are reprogrammed at high efficiency to a progenitor-like state, with these cells acting to orchestrate the nerve regeneration process. During nerve regeneration, SCs show little plasticity, maintaining their identity in the repaired tissue. However, once free of the nerve environment they appear to exhibit increased plasticity with reported roles in the repair of other tissues. In this review, we will discuss the mechanisms underlying the homeostasis and regeneration of peripheral nerves and how reprogrammed progenitor-like SCs have broader roles in the repair of other tissues with implications for pathologies such as cancer.
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Affiliation(s)
- Salome Stierli
- MRC LMCB, University College London, Gower Street, London, WC1E 6BT, UK
| | | | - Alison C Lloyd
- MRC LMCB, University College London, Gower Street, London, WC1E 6BT, UK
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