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Helmold BR, Ahrens A, Fitzgerald Z, Ozdinler PH. Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets. Neural Regen Res 2025; 20:725-739. [PMID: 38886938 DOI: 10.4103/nrr.nrr-d-23-02068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 04/05/2024] [Indexed: 06/20/2024] Open
Abstract
Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. Protein-protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as "causative" for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration-approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.
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Affiliation(s)
- Benjamin R Helmold
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Angela Ahrens
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Zachary Fitzgerald
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - P Hande Ozdinler
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Feinberg School of Medicine, Les Turner ALS Center at Northwestern University, Chicago, IL, USA
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Eck RJ, Stair JG, Kraemer BC, Liachko NF. Simple models to understand complex disease: 10 years of progress from Caenorhabditis elegans models of amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Front Neurosci 2024; 17:1300705. [PMID: 38239833 PMCID: PMC10794587 DOI: 10.3389/fnins.2023.1300705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 11/28/2023] [Indexed: 01/22/2024] Open
Abstract
The nematode Caenorhabditis elegans are a powerful model system to study human disease, with numerous experimental advantages including significant genetic and cellular homology to vertebrate animals, a short lifespan, and tractable behavioral, molecular biology and imaging assays. Beginning with the identification of SOD1 as a genetic cause of amyotrophic lateral sclerosis (ALS), C. elegans have contributed to a deeper understanding of the mechanistic underpinnings of this devastating neurodegenerative disease. More recently this work has expanded to encompass models of other types of ALS and the related disease frontotemporal lobar degeneration (FTLD-TDP), including those characterized by mutation or accumulation of the proteins TDP-43, C9orf72, FUS, HnRNPA2B1, ALS2, DCTN1, CHCHD10, ELP3, TUBA4A, CAV1, UBQLN2, ATXN3, TIA1, KIF5A, VAPB, GRN, and RAB38. In this review we summarize these models and the progress and insights from the last ten years of using C. elegans to study the neurodegenerative diseases ALS and FTLD-TDP.
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Affiliation(s)
- Randall J. Eck
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, United States
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
| | - Jade G. Stair
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
| | - Brian C. Kraemer
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, United States
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Nicole F. Liachko
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States
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3
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Chagas Monteiro KL, dos Santos Alcântara MG, de Aquino TM, Ferreira da Silva-Júnior E. Insights on Natural Products Against Amyotrophic Lateral Sclerosis (ALS). Curr Neuropharmacol 2024; 22:1169-1188. [PMID: 38708921 PMCID: PMC10964095 DOI: 10.2174/1570159x22666231016153606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 07/13/2023] [Accepted: 07/16/2023] [Indexed: 05/07/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that causes the death of motor neurons and consequent muscle paralysis. Despite many efforts to address it, current therapy targeting ALS remains limited, increasing the interest in complementary therapies. Over the years, several herbal preparations and medicinal plants have been studied to prevent and treat this disease, which has received remarkable attention due to their blood-brain barrier penetration properties and low toxicity. Thus, this review presents the therapeutic potential of a variety of medicinal herbs and their relationship with ALS and their physiopathological pathways.
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Affiliation(s)
- Kadja Luana Chagas Monteiro
- Research Group on Therapeutic Strategies - GPET, Laboratory of Synthesis and Research in Medicinal Chemistry - LSPMED, Institute of Chemistry and Biotechnology, Federal University of Alagoas, 57072-970, Maceió, Alagoas, Brazil
| | - Marcone Gomes dos Santos Alcântara
- Research Group on Therapeutic Strategies - GPET, Laboratory of Synthesis and Research in Medicinal Chemistry - LSPMED, Institute of Chemistry and Biotechnology, Federal University of Alagoas, 57072-970, Maceió, Alagoas, Brazil
| | - Thiago Mendonça de Aquino
- Research Group on Therapeutic Strategies - GPET, Laboratory of Synthesis and Research in Medicinal Chemistry - LSPMED, Institute of Chemistry and Biotechnology, Federal University of Alagoas, 57072-970, Maceió, Alagoas, Brazil
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Katiyar D, Singhal S, Bansal P, Nagarajan K, Grover P. Nutraceuticals and phytotherapeutics for holistic management of amyotrophic lateral sclerosis. 3 Biotech 2023; 13:62. [PMID: 36714551 PMCID: PMC9880136 DOI: 10.1007/s13205-023-03475-5] [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: 10/18/2022] [Accepted: 01/10/2023] [Indexed: 01/27/2023] Open
Abstract
Amyotrophic lateral sclerosis" (ALS) is a progressive neuronal disorder that affects sensory neurons in the brain and spinal cord, causing loss of muscle control. Moreover, additional neuronal subgroups as well as glial cells such as microglia, astrocytes, and oligodendrocytes are also thought to play a role in the aetiology. The disease affects upper motor neurons and lowers motor neurons and leads to that either lead to muscle weakness and wasting in the arms, legs, trunk and periventricular area. Oxidative stress, excitotoxicity, programmed cell death, altered neurofilament activity, anomalies in neurotransmission, abnormal protein processing and deterioration, increased inflammation, and mitochondrial dysfunction may all play a role in the progression of ALS. There are presently hardly FDA-approved drugs used to treat ALS, and they are only beneficial in slowing the progression of the disease and enhancing functions in certain individuals with ALS, not really in curing or preventing the illness. These days, researchers focus on understanding the pathogenesis of the disease by targeting several mechanisms aiming to develop successful treatments for ALS. This review discusses the epidemiology, risk factors, diagnosis, clinical features, pathophysiology, and disease management. The compilation focuses on alternative methods for the management of symptoms of ALS with nutraceuticals and phytotherapeutics.
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Affiliation(s)
- Deepti Katiyar
- KIET School of Pharmacy, KIET Group of Institutions, Delhi-NCR, Ghaziabad, Uttar Pradesh 201206 India
| | - Shipra Singhal
- KIET School of Pharmacy, KIET Group of Institutions, Delhi-NCR, Ghaziabad, Uttar Pradesh 201206 India
| | - Priya Bansal
- KIET School of Pharmacy, KIET Group of Institutions, Delhi-NCR, Ghaziabad, Uttar Pradesh 201206 India
| | - K. Nagarajan
- KIET School of Pharmacy, KIET Group of Institutions, Delhi-NCR, Ghaziabad, Uttar Pradesh 201206 India
| | - Parul Grover
- KIET School of Pharmacy, KIET Group of Institutions, Delhi-NCR, Ghaziabad, Uttar Pradesh 201206 India
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Han P, Mo S, Wang Z, Xu J, Fu X, Tian Y. UXT at the crossroads of cell death, immunity and neurodegenerative diseases. Front Oncol 2023; 13:1179947. [PMID: 37152054 PMCID: PMC10154696 DOI: 10.3389/fonc.2023.1179947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 04/03/2023] [Indexed: 05/09/2023] Open
Abstract
The ubiquitous expressed transcript (UXT), a member of the prefoldin-like protein family, modulates regulated cell death (RCD) such as apoptosis and autophagy-mediated cell death through nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), P53, P62, and methylation, and is involved in the regulation of cell metabolism, thereby affecting tumor progression. UXT also maintains immune homeostasis and reduces proteotoxicity in neuro-degenerative diseases through selective autophagy and molecular chaperones. Herein, we review and further elucidate the mechanisms by which UXT affects the regulation of cell death, maintenance of immune homeostasis, and neurodegenerative diseases and discuss the possible UXT involvement in the regulation of ferroptosis and immunogenic cell death, and targeting it to improve cancer treatment outcomes by regulating cell death and immune surveillance.
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Affiliation(s)
- Pengzhe Han
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences Tongji Shanxi Hospital, Taiyuan, China
| | - Shaojian Mo
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences Tongji Shanxi Hospital, Taiyuan, China
- Department of Biliary and Pancreatic Surgery, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
| | - Zhengwang Wang
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences Tongji Shanxi Hospital, Taiyuan, China
| | - Jiale Xu
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences Tongji Shanxi Hospital, Taiyuan, China
| | - Xifeng Fu
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences Tongji Shanxi Hospital, Taiyuan, China
- Department of Biliary and Pancreatic Surgery, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
| | - Yanzhang Tian
- Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences Tongji Shanxi Hospital, Taiyuan, China
- Department of Biliary and Pancreatic Surgery, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Taiyuan, China
- *Correspondence: Yanzhang Tian,
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Cozzi M, Ferrari V. Autophagy Dysfunction in ALS: from Transport to Protein Degradation. J Mol Neurosci 2022; 72:1456-1481. [PMID: 35708843 PMCID: PMC9293831 DOI: 10.1007/s12031-022-02029-3] [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: 02/28/2022] [Accepted: 05/17/2022] [Indexed: 01/18/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting upper and lower motor neurons (MNs). Since the identification of the first ALS mutation in 1993, more than 40 genes have been associated with the disorder. The most frequent genetic causes of ALS are represented by mutated genes whose products challenge proteostasis, becoming unable to properly fold and consequently aggregating into inclusions that impose proteotoxic stress on affected cells. In this context, increasing evidence supports the central role played by autophagy dysfunctions in the pathogenesis of ALS. Indeed, in early stages of disease, high levels of proteins involved in autophagy are present in ALS MNs; but at the same time, with neurodegeneration progression, autophagy-mediated degradation decreases, often as a result of the accumulation of toxic protein aggregates in affected cells. Autophagy is a complex multistep pathway that has a central role in maintaining cellular homeostasis. Several proteins are involved in its tight regulation, and importantly a relevant fraction of ALS-related genes encodes products that directly take part in autophagy, further underlining the relevance of this key protein degradation system in disease onset and progression. In this review, we report the most relevant findings concerning ALS genes whose products are involved in the several steps of the autophagic pathway, from phagophore formation to autophagosome maturation and transport and finally to substrate degradation.
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Affiliation(s)
- Marta Cozzi
- Dipartimento Di Scienze Farmacologiche E Biomolecolari, Università Degli Studi Di Milano, 20133, Milan, Italy.
| | - Veronica Ferrari
- Dipartimento Di Scienze Farmacologiche E Biomolecolari, Università Degli Studi Di Milano, 20133, Milan, Italy.
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Mai Le N, Li J. Ras-related C3 botulinum toxin substrate 1 role in Pathophysiology of Neurological diseases. BRAIN HEMORRHAGES 2022. [DOI: 10.1016/j.hest.2022.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Miceli M, Exertier C, Cavaglià M, Gugole E, Boccardo M, Casaluci RR, Ceccarelli N, De Maio A, Vallone B, Deriu MA. ALS2-Related Motor Neuron Diseases: From Symptoms to Molecules. BIOLOGY 2022; 11:77. [PMID: 35053075 PMCID: PMC8773251 DOI: 10.3390/biology11010077] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/22/2021] [Accepted: 12/29/2021] [Indexed: 11/27/2022]
Abstract
Infantile-onset Ascending Hereditary Spastic Paralysis, Juvenile Primary Lateral Sclerosis and Juvenile Amyotrophic Lateral Sclerosis are all motor neuron diseases related to mutations on the ALS2 gene, encoding for a 1657 amino acids protein named Alsin. This ~185 kDa multi-domain protein is ubiquitously expressed in various human tissues, mostly in the brain and the spinal cord. Several investigations have indicated how mutations within Alsin's structured domains may be responsible for the alteration of Alsin's native oligomerization state or Alsin's propensity to interact with protein partners. In this review paper, we propose a description of differences and similarities characterizing the above-mentioned ALS2-related rare neurodegenerative disorders, pointing attention to the effects of ALS2 mutation from molecule to organ and at the system level. Known cases were collected through a literature review and rationalized to deeply elucidate the neurodegenerative clinical outcomes as consequences of ALS2 mutations.
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Affiliation(s)
- Marcello Miceli
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
| | - Cécile Exertier
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”, Sapienza Università di Roma, 00185 Rome, Italy; (C.E.); (E.G.); (B.V.)
| | - Marco Cavaglià
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
| | - Elena Gugole
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”, Sapienza Università di Roma, 00185 Rome, Italy; (C.E.); (E.G.); (B.V.)
| | - Marta Boccardo
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
| | - Rossana Rita Casaluci
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
| | - Noemi Ceccarelli
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
| | - Alessandra De Maio
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
| | - Beatrice Vallone
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”, Sapienza Università di Roma, 00185 Rome, Italy; (C.E.); (E.G.); (B.V.)
| | - Marco A. Deriu
- PolitoBIOMedLab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy; (M.M.); (M.C.); (M.B.); (R.R.C.); (N.C.); (A.D.M.)
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9
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Kikuchi M, Sekiya M, Hara N, Miyashita A, Kuwano R, Ikeuchi T, Iijima KM, Nakaya A. Disruption of a RAC1-centred network is associated with Alzheimer's disease pathology and causes age-dependent neurodegeneration. Hum Mol Genet 2021; 29:817-833. [PMID: 31942999 PMCID: PMC7191305 DOI: 10.1093/hmg/ddz320] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/28/2019] [Accepted: 12/27/2019] [Indexed: 12/21/2022] Open
Abstract
The molecular biological mechanisms of Alzheimer’s disease (AD) involve disease-associated crosstalk through many genes and include a loss of normal as well as a gain of abnormal interactions among genes. A protein domain network (PDN) is a collection of physical bindings that occur between protein domains, and the states of the PDNs in patients with AD are likely to be perturbed compared to those in normal healthy individuals. To identify PDN changes that cause neurodegeneration, we analysed the PDNs that occur among genes co-expressed in each of three brain regions at each stage of AD. Our analysis revealed that the PDNs collapsed with the progression of AD stage and identified five hub genes, including Rac1, as key players in PDN collapse. Using publicly available as well as our own gene expression data, we confirmed that the mRNA expression level of the RAC1 gene was downregulated in the entorhinal cortex (EC) of AD brains. To test the causality of these changes in neurodegeneration, we utilized Drosophila as a genetic model and found that modest knockdown of Rac1 in neurons was sufficient to cause age-dependent behavioural deficits and neurodegeneration. Finally, we identified a microRNA, hsa-miR-101-3p, as a potential regulator of RAC1 in AD brains. As the Braak neurofibrillary tangle (NFT) stage progressed, the expression levels of hsa-miR-101-3p were increased specifically in the EC. Furthermore, overexpression of hsa-miR-101-3p in the human neuronal cell line SH-SY5Y caused RAC1 downregulation. These results highlight the utility of our integrated network approach for identifying causal changes leading to neurodegeneration in AD.
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Affiliation(s)
- Masataka Kikuchi
- Department of Genome Informatics, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Michiko Sekiya
- Department of Alzheimer's Disease Research, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Aichi 474-8511, Japan.,Department of Experimental Gerontology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Aichi 467-8603, Japan
| | - Norikazu Hara
- Department of Molecular Genetics, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Akinori Miyashita
- Department of Molecular Genetics, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Ryozo Kuwano
- Department of Molecular Genetics, Brain Research Institute, Niigata University, Niigata 951-8585, Japan.,Asahigawaso Medical-Welfare Center, Asahigawaso Research Institute, Okayama 703-8207, Japan
| | - Takeshi Ikeuchi
- Department of Molecular Genetics, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Koichi M Iijima
- Department of Alzheimer's Disease Research, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Aichi 474-8511, Japan.,Department of Experimental Gerontology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Aichi 467-8603, Japan
| | - Akihiro Nakaya
- Department of Genome Informatics, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
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Cid E, Marquez-Galera A, Valero M, Gal B, Medeiros DC, Navarron CM, Ballesteros-Esteban L, Reig-Viader R, Morales AV, Fernandez-Lamo I, Gomez-Dominguez D, Sato M, Hayashi Y, Bayés À, Barco A, Lopez-Atalaya JP, de la Prida LM. Sublayer- and cell-type-specific neurodegenerative transcriptional trajectories in hippocampal sclerosis. Cell Rep 2021; 35:109229. [PMID: 34107264 DOI: 10.1016/j.celrep.2021.109229] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 03/18/2021] [Accepted: 05/17/2021] [Indexed: 12/20/2022] Open
Abstract
Hippocampal sclerosis, the major neuropathological hallmark of temporal lobe epilepsy, is characterized by different patterns of neuronal loss. The mechanisms of cell-type-specific vulnerability and their progression and histopathological classification remain controversial. Using single-cell electrophysiology in vivo and immediate-early gene expression, we reveal that superficial CA1 pyramidal neurons are overactive in epileptic rodents. Bulk tissue and single-nucleus expression profiling disclose sublayer-specific transcriptomic signatures and robust microglial pro-inflammatory responses. Transcripts regulating neuronal processes such as voltage channels, synaptic signaling, and cell adhesion are deregulated differently by epilepsy across sublayers, whereas neurodegenerative signatures primarily involve superficial cells. Pseudotime analysis of gene expression in single nuclei and in situ validation reveal separated trajectories from health to epilepsy across cell types and identify a subset of superficial cells undergoing a later stage in neurodegeneration. Our findings indicate that sublayer- and cell-type-specific changes associated with selective CA1 neuronal damage contribute to progression of hippocampal sclerosis.
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Affiliation(s)
- Elena Cid
- Instituto Cajal, CSIC, 28002 Madrid, Spain
| | - Angel Marquez-Galera
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), 03550 Sant Joan d'Alacant, Alicante, Spain
| | | | - Beatriz Gal
- Instituto Cajal, CSIC, 28002 Madrid, Spain; Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain
| | | | - Carmen M Navarron
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), 03550 Sant Joan d'Alacant, Alicante, Spain
| | | | - Rita Reig-Viader
- Institut d'Investigació Biomèdica San Pau, 08041 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola del Vallès, Spain
| | | | | | | | - Masaaki Sato
- RIKEN Brain Science Institute, Wako, 351-0198 Saitama, Japan
| | - Yasunori Hayashi
- RIKEN Brain Science Institute, Wako, 351-0198 Saitama, Japan; Department of Pharmacology, Kyoto University Graduate School of Medicine, 606-8501 Kyoto, Japan
| | - Àlex Bayés
- Institut d'Investigació Biomèdica San Pau, 08041 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola del Vallès, Spain
| | - Angel Barco
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), 03550 Sant Joan d'Alacant, Alicante, Spain
| | - Jose P Lopez-Atalaya
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), 03550 Sant Joan d'Alacant, Alicante, Spain.
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11
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Mohi-Ud-Din R, Mir RH, Shah AJ, Sabreen S, Wani TU, Masoodi MH, Akkol EK, Bhat ZA, Khan H. Plant-Derived Natural Compounds for the treatment of Amyotrophic Lateral Sclerosis: An Update. Curr Neuropharmacol 2021; 20:179-193. [PMID: 33913406 PMCID: PMC9199545 DOI: 10.2174/1570159x19666210428120514] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/14/2021] [Accepted: 04/16/2021] [Indexed: 11/22/2022] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is a motor neuron disease (MND) that typically causes death within 3-5 years after diagnosis. Regardless of the substantial scientific knowledge accrued more than a century ago, truly effective therapeutic strategies remain distant. Various conventional drugs are being used but are having several adverse effects. Objective/Aim The current study aims to thoroughly review plant-derived compounds with well-defined ALS activities and their structure-activity relationships. Moreover, the review also focuses on complex genetics, clinical trials, and the use of natural products that might decrypt the future and novel therapeutics in ALS. Methods The collection of data for the compilation of this review work was searched in PubMed Scopus, Google Scholar, and Science Direct. Results Results showed that phytochemicals like-Ginkgolides, Protopanaxatriol, Genistein, epigallocatechingallate, resveratrol, cassoside, and others possess Amyotrophic lateral sclerosis (ALS) activity by various mechanisms. Conclusion These plant-derived compounds may be considered as supplements for conventional (ALS). Moreover, further preclinical and clinical studies are required to understand the structure-activity relationships, metabolism, absorption, and mechanisms of plant-derived natural agents.
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Affiliation(s)
- Roohi Mohi-Ud-Din
- Pharmacognosy & Phytochemistry Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar, 190006, Kashmir, India
| | - Reyaz Hassan Mir
- Pharmaceutical Chemistry Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar-190006, Kashmir, India
| | - Abdul Jalil Shah
- Pharmaceutical Chemistry Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar-190006, Kashmir, India
| | - Saba Sabreen
- Pharmaceutical Chemistry Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar-190006, Kashmir, India
| | - Taha Umair Wani
- Pharmaceutics Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar-190006, Kashmir, India
| | - Mubashir Hussain Masoodi
- Pharmaceutical Chemistry Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar-190006, Kashmir, India
| | - Esra Küpeli Akkol
- Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330, Ankara. Turkey
| | - Zulfiqar Ali Bhat
- Pharmacognosy & Phytochemistry Division, Department of Pharmaceutical Sciences, University of Kashmir, Hazratbal, Srinagar, 190006, Kashmir, India
| | - Haroon Khan
- Department of Pharmacy, Abdul Wali Khan University, Mardan, 23200. Pakistan
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Harre J, Heinkele L, Steffens M, Warnecke A, Lenarz T, Just I, Rohrbeck A. Potentiation of Brain-Derived Neurotrophic Factor-Induced Protection of Spiral Ganglion Neurons by C3 Exoenzyme/Rho Inhibitor. Front Cell Neurosci 2021; 15:602897. [PMID: 33776650 PMCID: PMC7991574 DOI: 10.3389/fncel.2021.602897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/19/2021] [Indexed: 11/17/2022] Open
Abstract
Preservation of the excitability of spiral ganglion neurons (SGN) may contribute to an improved speech perception after cochlear implantation. Thus, the application of exogenous neurotrophic factors such as the neurotrophin brain-derived neurotrophic factor (BDNF) to increase SGN survival in vitro and in vivo is a promising pharmacological approach in cochlear implant (CI) research. Due to the difficult pharmacokinetic profile of proteins such as BDNF, there is a quest for small molecules to mediate the survival of SGN or to increase the efficacy of BDNF. The C3 exoenzyme from Clostridium botulinum could be a potential new candidate for the protection and regeneration of SGN. Inhibition of the RhoA GTPase pathway which can be mediated by C3 is described as a promising strategy to enhance axonal regeneration and to exert pro-survival signals in neurons. Nanomolar concentrations of C3, its enzymatically inactive form C3E174Q, and a 26mer C-terminal peptide fragment covering amino acid 156–181 (C3156-181) potentiated the neuroprotective effect on SGN mediated by BDNF in vitro. The neuroprotective effect of C3/BDNF was reduced to the neuroprotective effect of BDNF alone after the treatment with wortmannin, an inhibitor of the phosphatidylinositol-3-kinase (PI3K).The exoenzyme C3 (wild-type and enzyme-deficient) and the C3 peptide fragment C3154–181 present novel biologically active compounds for the protection of the SGN. The exact underlying intracellular mechanisms that mediate the neuroprotective effect are not clarified yet, but the combination of BDNF (TrkB stimulation) and C3 exoenzyme (RhoA inhibition) can be used to protect SGN in vitro.
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Affiliation(s)
- Jennifer Harre
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 2177/1), Hannover, Germany
| | - Laura Heinkele
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Melanie Steffens
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 2177/1), Hannover, Germany
| | - Thomas Lenarz
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 2177/1), Hannover, Germany
| | - Ingo Just
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
| | - Astrid Rohrbeck
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
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13
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Jagaraj CJ, Parakh S, Atkin JD. Emerging Evidence Highlighting the Importance of Redox Dysregulation in the Pathogenesis of Amyotrophic Lateral Sclerosis (ALS). Front Cell Neurosci 2021; 14:581950. [PMID: 33679322 PMCID: PMC7929997 DOI: 10.3389/fncel.2020.581950] [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: 07/14/2020] [Accepted: 12/21/2020] [Indexed: 12/20/2022] Open
Abstract
The cellular redox state, or balance between cellular oxidation and reduction reactions, serves as a vital antioxidant defence system that is linked to all important cellular activities. Redox regulation is therefore a fundamental cellular process for aerobic organisms. Whilst oxidative stress is well described in neurodegenerative disorders including amyotrophic lateral sclerosis (ALS), other aspects of redox dysfunction and their contributions to pathophysiology are only just emerging. ALS is a fatal neurodegenerative disease affecting motor neurons, with few useful treatments. Hence there is an urgent need to develop more effective therapeutics in the future. Here, we discuss the increasing evidence for redox dysregulation as an important and primary contributor to ALS pathogenesis, which is associated with multiple disease mechanisms. Understanding the connection between redox homeostasis, proteins that mediate redox regulation, and disease pathophysiology in ALS, may facilitate a better understanding of disease mechanisms, and lead to the design of better therapeutic strategies.
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Affiliation(s)
- Cyril Jones Jagaraj
- Department of Biomedical Sciences, Macquarie University Centre for MND Research, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sonam Parakh
- Department of Biomedical Sciences, Macquarie University Centre for MND Research, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Julie D Atkin
- Department of Biomedical Sciences, Macquarie University Centre for MND Research, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC, Australia
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14
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Specific Akt Family Members Impair Stress-Mediated Transactivation of Viral Promoters and Enhance Neuronal Differentiation: Important Functions for Maintaining Latency. J Virol 2020; 94:JVI.00901-20. [PMID: 32796067 DOI: 10.1128/jvi.00901-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/30/2020] [Indexed: 01/02/2023] Open
Abstract
Neurotropic Alphaherpesvirinae subfamily members such as bovine herpesvirus 1 (BoHV-1) and herpes simplex virus 1 (HSV-1) establish and maintain lifelong latent infections in neurons. Following infection of ocular, oral, or nasal cavities, sensory neurons within trigeminal ganglia (TG) are an important site for latency. Certain external stressors can trigger reactivation from latency, in part because activation of the glucocorticoid receptor (GR) stimulates productive infection and promoters that drive expression of key viral transcriptional regulators. The Akt serine/threonine protein kinase family is linked to maintaining latency. For example, Akt3 is detected in more TG neurons during BoHV-1 latency than in reactivation and uninfected calves. Furthermore, Akt signaling correlates with maintaining HSV-1 latency in certain neuronal models of latency. Finally, an active Akt protein kinase is crucial for the ability of the HSV-1 latency-associated transcript (LAT) to inhibit apoptosis in neuronal cell lines. Consequently, we hypothesized that viral and/or cellular factors impair stress-induced transcription and reduce the incidence of reactivation triggered by low levels of stress. New studies demonstrate that Akt1 and Akt2, but not Akt3, significantly reduced GR-mediated transactivation of the BoHV-1 immediate early transcription unit 1 (IEtu1) promoter, the HSV-1 infected cell protein 0 (ICP0) promoter, and the mouse mammary tumor virus long terminal repeat (MMTV-LTR). Akt3, but not Akt1 or Akt2, significantly enhanced neurite formation in mouse neuroblastoma cells, which correlates with repairing damaged neurons. These studies suggest that unique biological properties of the three Akt family members promote the maintenance of latency in differentiated neurons.IMPORTANCE External stressful stimuli are known to increase the incidence of reactivation of Alphaherpesvirinae subfamily members. Activation of the glucocorticoid receptor (GR) by the synthetic corticosteroid dexamethasone (DEX) stimulates bovine herpesvirus 1 (BoHV-1) and herpes simplex virus 1 (HSV-1) reactivation. Furthermore, GR and dexamethasone stimulate productive infection and promoters that drive expression of viral transcriptional regulators. These observations lead us to predict that stress-induced transcription is impaired by factors abundantly expressed during latency. Interestingly, activation of the Akt family of serine/threonine protein kinases is linked to maintenance of latency. New studies reveal that Akt1 and Ak2, but not Akt3, impaired GR- and dexamethasone-mediated transactivation of the BoHV-1 immediate early transcription unit 1 and HSV-1 ICP0 promoters. Strikingly, Akt3, but not Akt1 or Akt2, stimulated neurite formation in mouse neuroblastoma cells, a requirement for neurogenesis. These studies provide insight into how Akt family members may promote the maintenance of lifelong latency.
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15
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Stankiewicz TR, Pena C, Bouchard RJ, Linseman DA. Dysregulation of Rac or Rho elicits death of motor neurons and activation of these GTPases is altered in the G93A mutant hSOD1 mouse model of amyotrophic lateral sclerosis. Neurobiol Dis 2020; 136:104743. [PMID: 31931138 DOI: 10.1016/j.nbd.2020.104743] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 12/18/2019] [Accepted: 01/08/2020] [Indexed: 12/11/2022] Open
Abstract
Rho GTPases play a central role in neuronal survival; however, the antagonistic relationship between Rac and Rho in the regulation of motor neuron survival remains poorly defined. In the current study, we demonstrate that treatment with NSC23766, a selective inhibitor of the Rac-specific guanine nucleotide exchange factors, Tiam1 and Trio, is sufficient to induce the death of embryonic stem cell (ESC)-derived motor neurons. The mode of cell death is primarily apoptotic and is characterized by caspase-3 activation, de-phosphorylation of ERK5 and AKT, and nuclear translocation of the BH3-only protein Bad. As opposed to the inhibition of Rac, motor neuron cell death is also induced by constitutive activation of Rho, via a mechanism that depends on Rho kinase (ROCK) activity. Investigation of Rac and Rho in the G93A mutant, human Cu, Zn-superoxide dismutase (hSOD1) mouse model of amyotrophic lateral sclerosis (ALS), revealed that active Rac1-GTP is markedly decreased in spinal cord motor neurons of transgenic mice at disease onset and end-stage, when compared to age-matched wild type (WT) littermates. Furthermore, although there is no significant change in active RhoA-GTP, total RhoB displays a striking redistribution from motor neuron nuclei in WT mouse spinal cord to motor neuron axons in end-stage G93A mutant hSOD1 mice. Collectively, these data suggest that the intricate balance between pro-survival Rac signaling and pro-apoptotic Rho/ROCK signaling is critical for motor neuron survival and therefore, disruption in the balance of their activities and/or localization may contribute to the death of motor neurons in ALS.
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Affiliation(s)
- Trisha R Stankiewicz
- University of Denver, Department of Biological Sciences, Denver, CO 80208, United States
| | - Claudia Pena
- University of Denver, Department of Biological Sciences, Denver, CO 80208, United States
| | - Ron J Bouchard
- Research Service, Veterans Affairs Medical Center, Denver, CO, 80220, United States
| | - Daniel A Linseman
- University of Denver, Department of Biological Sciences, Eleanor Roosevelt Institute, and Knoebel Institute for Healthy Aging, 2155 E. Wesley Ave., Denver, CO, 80208, United States.
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16
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Kim H, Calatayud C, Guha S, Fernández-Carasa I, Berkowitz L, Carballo-Carbajal I, Ezquerra M, Fernández-Santiago R, Kapahi P, Raya Á, Miranda-Vizuete A, Lizcano JM, Vila M, Caldwell KA, Caldwell GA, Consiglio A, Dalfo E. The Small GTPase RAC1/CED-10 Is Essential in Maintaining Dopaminergic Neuron Function and Survival Against α-Synuclein-Induced Toxicity. Mol Neurobiol 2018; 55:7533-7552. [PMID: 29429047 PMCID: PMC6096980 DOI: 10.1007/s12035-018-0881-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 01/07/2018] [Indexed: 12/22/2022]
Abstract
Parkinson's disease is associated with intracellular α-synuclein accumulation and ventral midbrain dopaminergic neuronal death in the Substantia Nigra of brain patients. The Rho GTPase pathway, mainly linking surface receptors to the organization of the actin and microtubule cytoskeletons, has been suggested to participate to Parkinson's disease pathogenesis. Nevertheless, its exact contribution remains obscure. To unveil the participation of the Rho GTPase family to the molecular pathogenesis of Parkinson's disease, we first used C elegans to demonstrate the role of the small GTPase RAC1 (ced-10 in the worm) in maintaining dopaminergic function and survival in the presence of alpha-synuclein. In addition, ced-10 mutant worms determined an increase of alpha-synuclein inclusions in comparison to control worms as well as an increase in autophagic vesicles. We then used a human neuroblastoma cells (M17) stably over-expressing alpha-synuclein and found that RAC1 function decreased the amount of amyloidogenic alpha-synuclein. Further, by using dopaminergic neurons derived from patients of familial LRRK2-Parkinson's disease we report that human RAC1 activity is essential in the regulation of dopaminergic cell death, alpha-synuclein accumulation, participates in neurite arborization and modulates autophagy. Thus, we determined for the first time that RAC1/ced-10 participates in Parkinson's disease associated pathogenesis and established RAC1/ced-10 as a new candidate for further investigation of Parkinson's disease associated mechanisms, mainly focused on dopaminergic function and survival against α-synuclein-induced toxicity.
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Affiliation(s)
- Hanna Kim
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
| | - Carles Calatayud
- Department of Pathology and Experimental Therapeutics, Bellvitge University Hospital-IDIBELL, 08028, L'Hospitalet de Llobregat, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), Barcelona, 08908, Spain
- Center of Regenerative Medicine in Barcelona (CMRB), Center for Networked Biomedical Research on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Hospital Duran i Reynals, 08908, L'Hospitalet de Llobregat, Spain
| | - Sanjib Guha
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA, 94945, USA
| | - Irene Fernández-Carasa
- Department of Pathology and Experimental Therapeutics, Bellvitge University Hospital-IDIBELL, 08028, L'Hospitalet de Llobregat, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), Barcelona, 08908, Spain
| | - Laura Berkowitz
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
| | - Iria Carballo-Carbajal
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035, Barcelona, Spain
| | - Mario Ezquerra
- Laboratory of Parkinson Disease and Other Neurodegenerative Movement Disorders, Department of Neurology: Clinical and Experimental Research, IDIBAPS - Hospital Clínic de Barcelona, 08036, Barcelona, Spain
| | - Rubén Fernández-Santiago
- Laboratory of Parkinson Disease and Other Neurodegenerative Movement Disorders, Department of Neurology: Clinical and Experimental Research, IDIBAPS - Hospital Clínic de Barcelona, 08036, Barcelona, Spain
| | - Pankaj Kapahi
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA, 94945, USA
| | - Ángel Raya
- Center of Regenerative Medicine in Barcelona (CMRB), Center for Networked Biomedical Research on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Hospital Duran i Reynals, 08908, L'Hospitalet de Llobregat, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), 08010, Barcelona, Spain
| | - Antonio Miranda-Vizuete
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/ Universidad de Sevilla, 41013, Sevilla, Spain
| | - Jose Miguel Lizcano
- Department of Biochemistry and Molecular Biology, Institut de Neurociències, Faculty of Medicine, M2, Universitat Autònoma de Barcelona (UAB), Bellaterra Campus, Cerdanyola del Vallés, Barcelona, Spain
| | - Miquel Vila
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035, Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), 08010, Barcelona, Spain
- Department of Biochemistry and Molecular Biology, Institut de Neurociències, Faculty of Medicine, M2, Universitat Autònoma de Barcelona (UAB), Bellaterra Campus, Cerdanyola del Vallés, Barcelona, Spain
| | - Kim A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
| | - Guy A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
| | - Antonella Consiglio
- Department of Pathology and Experimental Therapeutics, Bellvitge University Hospital-IDIBELL, 08028, L'Hospitalet de Llobregat, Spain.
- Institute of Biomedicine of the University of Barcelona (IBUB), Barcelona, 08908, Spain.
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Spain.
| | - Esther Dalfo
- Department of Biochemistry and Molecular Biology, Institut de Neurociències, Faculty of Medicine, M2, Universitat Autònoma de Barcelona (UAB), Bellaterra Campus, Cerdanyola del Vallés, Barcelona, Spain.
- Faculty of Medicine, University of Vic-Central University of Catalonia (UVic-UCC), Can Baumann, 08500, Vic, Spain.
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17
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Workman A, Zhu L, Keel BN, Smith TPL, Jones C. The Wnt Signaling Pathway Is Differentially Expressed during the Bovine Herpesvirus 1 Latency-Reactivation Cycle: Evidence That Two Protein Kinases Associated with Neuronal Survival, Akt3 and BMPR2, Are Expressed at Higher Levels during Latency. J Virol 2018; 92:e01937-17. [PMID: 29321317 PMCID: PMC5972910 DOI: 10.1128/jvi.01937-17] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/04/2018] [Indexed: 12/20/2022] Open
Abstract
Sensory neurons in trigeminal ganglia (TG) of calves latently infected with bovine herpesvirus 1 (BoHV-1) abundantly express latency-related (LR) gene products, including a protein (ORF2) and two micro-RNAs. Recent studies in mouse neuroblastoma cells (Neuro-2A) demonstrated ORF2 interacts with β-catenin and a β-catenin coactivator, high-mobility group AT-hook 1 (HMGA1) protein, which correlates with increased β-catenin-dependent transcription and cell survival. β-Catenin and HMGA1 are readily detected in a subset of latently infected TG neurons but not TG neurons from uninfected calves or reactivation from latency. Consequently, we hypothesized that the Wnt/β-catenin signaling pathway is differentially expressed during the latency and reactivation cycle and an active Wnt pathway promotes latency. RNA-sequencing studies revealed that 102 genes associated with the Wnt/β-catenin signaling pathway were differentially expressed in TG during the latency-reactivation cycle in calves. Wnt agonists were generally expressed at higher levels during latency, but these levels decreased during dexamethasone-induced reactivation. The Wnt agonist bone morphogenetic protein receptor 2 (BMPR2) was intriguing because it encodes a serine/threonine receptor kinase that promotes neuronal differentiation and inhibits cell death. Another differentially expressed gene encodes a protein kinase (Akt3), which is significant because Akt activity enhances cell survival and is linked to herpes simplex virus 1 latency and neuronal survival. Additional studies demonstrated ORF2 increased Akt3 steady-state protein levels and interacted with Akt3 in transfected Neuro-2A cells, which correlated with Akt3 activation. Conversely, expression of Wnt antagonists increased during reactivation from latency. Collectively, these studies suggest Wnt signaling cooperates with LR gene products, in particular ORF2, to promote latency.IMPORTANCE Lifelong BoHV-1 latency primarily occurs in sensory neurons. The synthetic corticosteroid dexamethasone consistently induces reactivation from latency in calves. RNA sequencing studies revealed 102 genes associated with the Wnt/β-catenin signaling pathway are differentially regulated during the latency-reactivation cycle. Two protein kinases associated with the Wnt pathway, Akt3 and BMPR2, were expressed at higher levels during latency but were repressed during reactivation. Furthermore, five genes encoding soluble Wnt antagonists and β-catenin-dependent transcription inhibitors were induced during reactivation from latency. These findings are important because Wnt, BMPR2, and Akt3 promote neurogenesis and cell survival, processes crucial for lifelong viral latency. In transfected neuroblastoma cells, a viral protein expressed during latency (ORF2) interacts with and enhances Akt3 protein kinase activity. These findings provide insight into how cellular factors associated with the Wnt signaling pathway cooperate with LR gene products to regulate the BoHV-1 latency-reactivation cycle.
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Affiliation(s)
- Aspen Workman
- United States Department of Agriculture, Agricultural Research Service, U.S. Meat Animal Research Center, Clay Center, Nebraska, USA
| | - Liqian Zhu
- Oklahoma State University Center for Veterinary Health Sciences, Department of Veterinary Pathobiology, Stillwater, Oklahoma, USA
- College of Veterinary Medicine and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, China
| | - Brittney N Keel
- United States Department of Agriculture, Agricultural Research Service, U.S. Meat Animal Research Center, Clay Center, Nebraska, USA
| | - Timothy P L Smith
- United States Department of Agriculture, Agricultural Research Service, U.S. Meat Animal Research Center, Clay Center, Nebraska, USA
| | - Clinton Jones
- Oklahoma State University Center for Veterinary Health Sciences, Department of Veterinary Pathobiology, Stillwater, Oklahoma, USA
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18
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Wu N, Ren D, Li S, Ma W, Hu S, Jin Y, Xiao S. RCC2 over-expression in tumor cells alters apoptosis and drug sensitivity by regulating Rac1 activation. BMC Cancer 2018; 18:67. [PMID: 29321004 PMCID: PMC5763756 DOI: 10.1186/s12885-017-3908-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 12/13/2017] [Indexed: 12/31/2022] Open
Abstract
Background Small GTP binding protein Rac1 is a component of NADPH oxidases and is essential for superoxide-induced cell death. Rac1 is activated by guanine nucleotide exchange factors (GEFs), and this activation can be blocked by regulator of chromosome condensation 2 (RCC2), which binds the switch regions of Rac1 to prevent access from GEFs. Methods Three cancer cell lines with up- or down-regulation of RCC2 were used to evaluate cell proliferation, apoptosis, Rac1 signaling and sensitivity to a group of nine chemotherapeutic drugs. RCC2 expression in lung cancer and ovarian cancer were studied using immunochemistry stain of tumor tissue arrays. Results Forced RCC2 expression in tumor cells blocked spontaneous- or Staurosporine (STS)-induced apoptosis. In contrast, RCC2 knock down in these cells resulted in increased apoptosis to STS treatment. The protective activity of RCC2 on apoptosis was revoked by a constitutively activated Rac1, confirming a role of RCC2 in apoptosis by regulating Rac1. In an immunohistochemistry evaluation of tissue microarray, RCC2 was over-expressed in 88.3% of primary lung cancer and 65.2% of ovarian cancer as compared to non-neoplastic lung and ovarian tissues, respectively. Because chemotherapeutic drugs can kill tumor cells by activating Rac1/JNK pathway, we suspect that tumors with RCC2 overexpression would be more resistant to these drugs. Tumor cells with forced RCC2 expression indeed had significant difference in drug sensitivity compared to parental cells using a panel of common chemotherapeutic drugs. Conclusions RCC2 regulates apoptosis by blocking Rac1 signaling. RCC2 expression in tumor can be a useful marker for predicting chemotherapeutic response.
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Affiliation(s)
- Nan Wu
- Department of Medical Genetics, Harbin Medical University, Harbin, China
| | - Dong Ren
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Su Li
- Department of Medical Genetics, Harbin Medical University, Harbin, China
| | - Wenli Ma
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Shaoyan Hu
- Children's Hospital of Soochow University, Suzhou, China
| | - Yan Jin
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.,Department of Medical Genetics, Harbin Medical University, Harbin, China.,Key Laboratory of Cardiovascular Medicine Research, Harbin Medical University, Ministry of Education, Harbin, China
| | - Sheng Xiao
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
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19
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Marei H, Malliri A. Rac1 in human diseases: The therapeutic potential of targeting Rac1 signaling regulatory mechanisms. Small GTPases 2017; 8:139-163. [PMID: 27442895 PMCID: PMC5584733 DOI: 10.1080/21541248.2016.1211398] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 07/05/2016] [Accepted: 07/05/2016] [Indexed: 12/11/2022] Open
Abstract
Abnormal Rac1 signaling is linked to a number of debilitating human diseases, including cancer, cardiovascular diseases and neurodegenerative disorders. As such, Rac1 represents an attractive therapeutic target, yet the search for effective Rac1 inhibitors is still underway. Given the adverse effects associated with Rac1 signaling perturbation, cells have evolved several mechanisms to ensure the tight regulation of Rac1 signaling. Thus, characterizing these mechanisms can provide invaluable information regarding major cellular events that lead to aberrant Rac1 signaling. Importantly, this information can be utilized to further facilitate the development of effective pharmacological modulators that can restore normal Rac1 signaling. In this review, we focus on the pathological role of Rac1 signaling, highlighting the benefits and potential drawbacks of targeting Rac1 in a clinical setting. Additionally, we provide an overview of available compounds that target key Rac1 regulatory mechanisms and discuss future therapeutic avenues arising from our understanding of these mechanisms.
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Affiliation(s)
- Hadir Marei
- Cell Signaling Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, UK
| | - Angeliki Malliri
- Cell Signaling Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, UK
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20
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Hadano S, Mitsui S, Pan L, Otomo A, Kubo M, Sato K, Ono S, Onodera W, Abe K, Chen X, Koike M, Uchiyama Y, Aoki M, Warabi E, Yamamoto M, Ishii T, Yanagawa T, Shang HF, Yoshii F. Functional links between SQSTM1 and ALS2 in the pathogenesis of ALS: cumulative impact on the protection against mutant SOD1-mediated motor dysfunction in mice. Hum Mol Genet 2016; 25:3321-3340. [PMID: 27439389 DOI: 10.1093/hmg/ddw180] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 06/06/2016] [Accepted: 06/08/2016] [Indexed: 02/05/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by a selective loss of motor neurons in the brain and spinal cord. Multiple toxicity pathways, such as oxidative stress, misfolded protein accumulation, and dysfunctional autophagy, are implicated in the pathogenesis of ALS. However, the molecular basis of the interplay between such multiple factors in vivo remains unclear. Here, we report that two independent ALS-linked autophagy-associated gene products; SQSTM1/p62 and ALS2/alsin, but not antioxidant-related factor; NFE2L2/Nrf2, are implicated in the pathogenesis in mutant SOD1 transgenic ALS models. We generated SOD1H46R mice either on a Nfe2l2-null, Sqstm1-null, or Sqstm1/Als2-double null background. Loss of SQSTM1 but not NFE2L2 exacerbated disease symptoms. A simultaneous inactivation of SQSTM1 and ALS2 further accelerated the onset of disease. Biochemical analyses revealed that loss of SQSTM1 increased the level of insoluble SOD1 at the intermediate stage of the disease, whereas no further elevation occurred at the end-stage. Notably, absence of SQSTM1 rather suppressed the mutant SOD1-dependent accumulation of insoluble polyubiquitinated proteins, while ALS2 loss enhanced it. Histopathological examinations demonstrated that loss of SQSTM1 accelerated motor neuron degeneration with accompanying the preferential accumulation of ubiquitin-positive aggregates in spinal neurons. Since SQSTM1 loss is more detrimental to SOD1H46R mice than lack of ALS2, the selective accumulation of such aggregates in neurons might be more insulting than the biochemically-detectable insoluble proteins. Collectively, two ALS-linked factors, SQSTM1 and ALS2, have distinct but additive protective roles against mutant SOD1-mediated toxicity by modulating neuronal proteostasis possibly through the autophagy-endolysosomal system.
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Affiliation(s)
- Shinji Hadano
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan .,Research Center for Brain and Nervous Diseases, Tokai University Graduate School of Medicine, Isehara, Kanagawa, Japan.,The Institute of Medical Sciences, Tokai University, Isehara, Kanagawa, Japan
| | - Shun Mitsui
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Lei Pan
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Asako Otomo
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan.,The Institute of Medical Sciences, Tokai University, Isehara, Kanagawa, Japan.,Micro/Nano Technology Center, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Mizuki Kubo
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Kai Sato
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Suzuka Ono
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Wakana Onodera
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Koichiro Abe
- Department of Molecular Life Sciences, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - XuePing Chen
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Masato Koike
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Yasuo Uchiyama
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Masashi Aoki
- Department of Neurology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Eiji Warabi
- Faculty of Medicine, University of Tsukuba, Tennoudai, Tsukuba, Ibaraki, Japan
| | - Masayuki Yamamoto
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Tetsuro Ishii
- Faculty of Medicine, University of Tsukuba, Tennoudai, Tsukuba, Ibaraki, Japan
| | - Toru Yanagawa
- Faculty of Medicine, University of Tsukuba, Tennoudai, Tsukuba, Ibaraki, Japan
| | - Hui-Fang Shang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Fumihito Yoshii
- The Institute of Medical Sciences, Tokai University, Isehara, Kanagawa, Japan.,Department of Neurology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
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21
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Gautam M, Jara JH, Sekerkova G, Yasvoina MV, Martina M, Özdinler PH. Absence of alsin function leads to corticospinal motor neuron vulnerability via novel disease mechanisms. Hum Mol Genet 2016; 25:1074-87. [PMID: 26755825 PMCID: PMC4764190 DOI: 10.1093/hmg/ddv631] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 12/29/2015] [Indexed: 12/11/2022] Open
Abstract
Mutations in the ALS2 gene result in early-onset amyotrophic lateral sclerosis, infantile-onset ascending hereditary spastic paraplegia and juvenile primary lateral sclerosis, suggesting prominent upper motor neuron involvement. However, the importance of alsin function for corticospinal motor neuron (CSMN) health and stability remains unknown. To date, four separate alsin knockout (AlsinKO) mouse models have been generated, and despite hopes of mimicking human pathology, none displayed profound motor function defects. This, however, does not rule out the possibility of neuronal defects within CSMN, which is not easy to detect in these mice. Detailed cellular analysis of CSMN has been hampered due to their limited numbers and the complex and heterogeneous structure of the cerebral cortex. In an effort to visualize CSMN in vivo and to investigate precise aspects of neuronal abnormalities in the absence of alsin function, we generated AlsinKO-UeGFP mice, by crossing AlsinKO and UCHL1-eGFP mice, a CSMN reporter line. We find that CSMN display vacuolated apical dendrites with increased autophagy, shrinkage of soma size and axonal pathology even in the pons region. Immunocytochemistry coupled with electron microscopy reveal that alsin is important for maintaining cellular cytoarchitecture and integrity of cellular organelles. In its absence, CSMN displays selective defects both in mitochondria and Golgi apparatus. UCHL1-eGFP mice help understand the underlying cellular factors that lead to CSMN vulnerability in diseases, and our findings reveal unique importance of alsin function for CSMN health and stability.
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Affiliation(s)
| | | | - Gabriella Sekerkova
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Marco Martina
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - P Hande Özdinler
- Department of Neurology and, Robert H. Lurie Comprehensive Cancer Center and Cognitive Neurology and Alzheimer's Disease Center, Northwestern University, Chicago, IL 60611, USA
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22
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Regulating Rac in the nervous system: molecular function and disease implication of Rac GEFs and GAPs. BIOMED RESEARCH INTERNATIONAL 2015; 2015:632450. [PMID: 25879033 PMCID: PMC4388020 DOI: 10.1155/2015/632450] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 03/06/2015] [Indexed: 12/11/2022]
Abstract
Rho family GTPases, including RhoA, Rac1, and Cdc42 as the most studied members, are master regulators of actin cytoskeletal organization. Rho GTPases control various aspects of the nervous system and are associated with a number of neuropsychiatric and neurodegenerative diseases. The activity of Rho GTPases is controlled by two families of regulators, guanine nucleotide exchange factors (GEFs) as the activators and GTPase-activating proteins (GAPs) as the inhibitors. Through coordinated regulation by GEFs and GAPs, Rho GTPases act as converging signaling molecules that convey different upstream signals in the nervous system. So far, more than 70 members of either GEFs or GAPs of Rho GTPases have been identified in mammals, but only a small subset of them have well-known functions. Thus, characterization of important GEFs and GAPs in the nervous system is crucial for the understanding of spatiotemporal dynamics of Rho GTPase activity in different neuronal functions. In this review, we summarize the current understanding of GEFs and GAPs for Rac1, with emphasis on the molecular function and disease implication of these regulators in the nervous system.
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23
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Stankiewicz TR, Ramaswami SA, Bouchard RJ, Aktories K, Linseman DA. Neuronal apoptosis induced by selective inhibition of Rac GTPase versus global suppression of Rho family GTPases is mediated by alterations in distinct mitogen-activated protein kinase signaling cascades. J Biol Chem 2015; 290:9363-76. [PMID: 25666619 DOI: 10.1074/jbc.m114.575217] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Indexed: 12/11/2022] Open
Abstract
Rho family GTPases play integral roles in neuronal differentiation and survival. We have shown previously that Clostridium difficile toxin B (ToxB), an inhibitor of RhoA, Rac1, and Cdc42, induces apoptosis of cerebellar granule neurons (CGNs). In this study, we compared the effects of ToxB to a selective inhibitor of the Rac-specific guanine nucleotide exchange factors Tiam1 and Trio (NSC23766). In a manner similar to ToxB, selective inhibition of Rac induces CGN apoptosis associated with enhanced caspase-3 activation and reduced phosphorylation of the Rac effector p21-activated kinase. In contrast to ToxB, caspase inhibitors do not protect CGNs from targeted inhibition of Rac. Also dissimilar to ToxB, selective inhibition of Rac does not inhibit MEK1/2/ERK1/2 or activate JNK/c-Jun. Instead, targeted inhibition of Rac suppresses distinct MEK5/ERK5, p90Rsk, and Akt-dependent signaling cascades known to regulate the localization and expression of the Bcl-2 homology 3 domain-only protein Bad. Adenoviral expression of a constitutively active mutant of MEK5 is sufficient to attenuate neuronal cell death induced by selective inhibition of Rac with NSC23766 but not apoptosis induced by global inhibition of Rho GTPases with ToxB. Collectively, these data demonstrate that global suppression of Rho family GTPases with ToxB causes a loss of MEK1/2/ERK1/2 signaling and activation of JNK/c-Jun, resulting in diminished degradation and enhanced transcription of the Bcl-2 homology 3 domain-only protein Bim. In contrast, selective inhibition of Rac induces CGN apoptosis by repressing unique MEK5/ERK5, p90Rsk, and Akt-dependent prosurvival pathways, ultimately leading to enhanced expression, dephosphorylation, and mitochondrial localization of proapoptotic Bad.
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Affiliation(s)
- Trisha R Stankiewicz
- From the Research Service, Veterans Affairs Medical Center, Denver, Colorado 80220, the Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado 80208
| | - Sai Anandi Ramaswami
- the Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado 80208
| | - Ron J Bouchard
- From the Research Service, Veterans Affairs Medical Center, Denver, Colorado 80220
| | - Klaus Aktories
- the Institute for Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany, and
| | - Daniel A Linseman
- From the Research Service, Veterans Affairs Medical Center, Denver, Colorado 80220, the Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado 80208, the Division of Clinical Pharmacology and Toxicology, Department of Medicine and Neuroscience Program, University of Colorado Denver, Aurora, Colorado 80045
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24
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Schäker K, Bartsch S, Patry C, Stoll SJ, Hillebrands JL, Wieland T, Kroll J. The bipartite rac1 Guanine nucleotide exchange factor engulfment and cell motility 1/dedicator of cytokinesis 180 (elmo1/dock180) protects endothelial cells from apoptosis in blood vessel development. J Biol Chem 2015; 290:6408-18. [PMID: 25586182 DOI: 10.1074/jbc.m114.633701] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Engulfment and cell motility 1/dedicator of cytokinesis 180 (Elmo1/Dock180) is a bipartite guanine nucleotide exchange factor for the monomeric GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1). Elmo1/Dock180 regulates Rac1 activity in a specific spatiotemporal manner in endothelial cells (ECs) during zebrafish development and acts downstream of the Netrin-1/Unc5-homolog B (Unc5B) signaling cascade. However, mechanistic details on the pathways by which Elmo1/Dock180 regulates endothelial function and vascular development remained elusive. In this study, we aimed to analyze the vascular function of Elmo1 and Dock180 in human ECs and during vascular development in zebrafish embryos. In vitro overexpression of Elmo1 and Dock180 in ECs reduced caspase-3/7 activity and annexin V-positive cell number upon induction of apoptosis. This protective effect of Elmo1 and Dock180 is mediated by activation of Rac1, p21-activated kinase (PAK) and AKT/protein kinase B (AKT) signaling. In zebrafish, Elmo1 and Dock180 overexpression reduced the total apoptotic cell and apoptotic EC number and promoted the formation of blood vessels during embryogenesis. In conclusion, Elmo1 and Dock180 protect ECs from apoptosis by the activation of the Rac1/PAK/AKT signaling cascade in vitro and in vivo. Thus, Elmo1 and Dock180 facilitate blood vessel formation by stabilization of the endothelium during angiogenesis.
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Affiliation(s)
- Kathrin Schäker
- From the Department of Vascular Biology and Tumor Angiogenesis, Center for Biomedicine and Medical Technology Mannheim (CBTM) and Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany, and
| | - Susanne Bartsch
- From the Department of Vascular Biology and Tumor Angiogenesis, Center for Biomedicine and Medical Technology Mannheim (CBTM) and
| | - Christian Patry
- From the Department of Vascular Biology and Tumor Angiogenesis, Center for Biomedicine and Medical Technology Mannheim (CBTM) and
| | - Sandra J Stoll
- From the Department of Vascular Biology and Tumor Angiogenesis, Center for Biomedicine and Medical Technology Mannheim (CBTM) and
| | - Jan-Luuk Hillebrands
- Department of Pathology and Medical Biology, Division of Pathology, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
| | - Thomas Wieland
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty Mannheim of Heidelberg University, 68167 Mannheim, Germany
| | - Jens Kroll
- From the Department of Vascular Biology and Tumor Angiogenesis, Center for Biomedicine and Medical Technology Mannheim (CBTM) and Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany, and
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25
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Stankiewicz TR, Linseman DA. Rho family GTPases: key players in neuronal development, neuronal survival, and neurodegeneration. Front Cell Neurosci 2014; 8:314. [PMID: 25339865 PMCID: PMC4187614 DOI: 10.3389/fncel.2014.00314] [Citation(s) in RCA: 278] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/18/2014] [Indexed: 12/11/2022] Open
Abstract
The Rho family of GTPases belongs to the Ras superfamily of low molecular weight (∼21 kDa) guanine nucleotide binding proteins. The most extensively studied members are RhoA, Rac1, and Cdc42. In the last few decades, studies have demonstrated that Rho family GTPases are important regulatory molecules that link surface receptors to the organization of the actin and microtubule cytoskeletons. Indeed, Rho GTPases mediate many diverse critical cellular processes, such as gene transcription, cell–cell adhesion, and cell cycle progression. However, Rho GTPases also play an essential role in regulating neuronal morphology. In particular, Rho GTPases regulate dendritic arborization, spine morphogenesis, growth cone development, and axon guidance. In addition, more recent efforts have underscored an important function for Rho GTPases in regulating neuronal survival and death. Interestingly, Rho GTPases can exert either a pro-survival or pro-death signal in neurons depending upon both the cell type and neurotoxic insult involved. This review summarizes key findings delineating the involvement of Rho GTPases and their effectors in the regulation of neuronal survival and death. Collectively, these results suggest that dysregulation of Rho family GTPases may potentially underscore the etiology of some forms of neurodegenerative disease such as amyotrophic lateral sclerosis.
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Affiliation(s)
- Trisha R Stankiewicz
- Research Service, Veterans Affairs Medical Center Denver, CO, USA ; Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver Denver, CO, USA
| | - Daniel A Linseman
- Research Service, Veterans Affairs Medical Center Denver, CO, USA ; Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver Denver, CO, USA ; Division of Clinical Pharmacology and Toxicology, Department of Medicine and Neuroscience Program, University of Colorado Denver Aurora, CO, USA
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26
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D'Ambrosi N, Rossi S, Gerbino V, Cozzolino M. Rac1 at the crossroad of actin dynamics and neuroinflammation in Amyotrophic Lateral Sclerosis. Front Cell Neurosci 2014; 8:279. [PMID: 25249940 PMCID: PMC4157560 DOI: 10.3389/fncel.2014.00279] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 08/22/2014] [Indexed: 12/11/2022] Open
Abstract
Rac1 is a major player of the Rho family of small GTPases that controls multiple cell signaling pathways, such as the organization of cytoskeleton (including adhesion and motility), cell proliferation, apoptosis and activation of immune cells. In the nervous system, in particular, Rac1 GTPase plays a key regulatory function of both actin and microtubule cytoskeletal dynamics and thus it is central to axonal growth and stability, as well as dendrite and spine structural plasticity. Rac1 is also a crucial regulator of NADPH-dependent membrane oxidase (NOX), a prominent source of reactive oxygen species (ROS), thus having a central role in the inflammatory response and neurotoxicity mediated by microglia cells in the nervous system. As such, alterations in Rac1 activity might well be involved in the processes that give rise to Amyotrophic Lateral Sclerosis (ALS), a complex syndrome where cytoskeletal disturbances in motor neurons and redox alterations in the inflammatory compartment play pivotal and synergic roles in the final disease outcomes. Here we will discuss the genetic and mechanistic evidence indicating the relevance of Rac1 dysregulation in the pathogenesis of ALS.
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Affiliation(s)
- Nadia D'Ambrosi
- Institute of Anatomy and Cell Biology, Università Cattolica del Sacro Cuore Rome, Italy
| | - Simona Rossi
- National Research Council, Institute of Translational Pharmacology Rome, Italy ; Fondazione Santa Lucia IRCCS Rome, Italy
| | - Valeria Gerbino
- Fondazione Santa Lucia IRCCS Rome, Italy ; Department of Biology, Università di Roma Tor Vergata Rome, Italy
| | - Mauro Cozzolino
- National Research Council, Institute of Translational Pharmacology Rome, Italy
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27
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Neuroprotective effects of C3 exoenzyme in excitotoxic retinopathy. Exp Eye Res 2014; 125:128-34. [PMID: 24928315 DOI: 10.1016/j.exer.2014.05.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/07/2014] [Accepted: 05/31/2014] [Indexed: 02/05/2023]
Abstract
The purpose of this study is to evaluate the neuroprotective effects of C3 exoenzyme (C3) on N-methyl-d-aspartate (NMDA)-induced retinopathy in rats. C3 was expressed in Escherichia. coli and purified by affinity chromatography. Immunofluorescence was performed in NIH 3T3 cells treated with C3 to verify the cellular uptake of the protein. NMDA was injected intravitreally into rat eyes with or without C3. At various time points after injection, eyes were enucleated. Hematoxylin/eosin staining was performed on retina cross-sections for morphological analysis. Survival and apoptosis of cells in the ganglion cell layer (GCL) were assessed by cresyl violet staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) on retina flat-mounts. RhoA levels in retina cells were evaluated by Western blot to detect C3 uptake in vivo. The cellular uptake of C3 was verified by immunofluorescence. Damage including a decrease in inner plexiform layer (IPL) thickness and reduction of cell density in the GCL, corresponding to apoptosis of neurons, was induced by intravitreal injection of NMDA. Protection against this damage was observed following co-injection of C3 and NMDA. RhoA ADP-ribosylation induced by C3 was confirmed by Western blot. Our results suggest that C3 exerts neuroprotective effects against excitotoxic damage induced by NMDA.
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28
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Cook DR, Rossman KL, Der CJ. Rho guanine nucleotide exchange factors: regulators of Rho GTPase activity in development and disease. Oncogene 2013; 33:4021-35. [PMID: 24037532 DOI: 10.1038/onc.2013.362] [Citation(s) in RCA: 286] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 06/25/2013] [Accepted: 06/26/2013] [Indexed: 12/16/2022]
Abstract
The aberrant activity of Ras homologous (Rho) family small GTPases (20 human members) has been implicated in cancer and other human diseases. However, in contrast to the direct mutational activation of Ras found in cancer and developmental disorders, Rho GTPases are activated most commonly in disease by indirect mechanisms. One prevalent mechanism involves aberrant Rho activation via the deregulated expression and/or activity of Rho family guanine nucleotide exchange factors (RhoGEFs). RhoGEFs promote formation of the active GTP-bound state of Rho GTPases. The largest family of RhoGEFs is comprised of the Dbl family RhoGEFs with 70 human members. The multitude of RhoGEFs that activate a single Rho GTPase reflects the very specific role of each RhoGEF in controlling distinct signaling mechanisms involved in Rho activation. In this review, we summarize the role of Dbl RhoGEFs in development and disease, with a focus on Ect2 (epithelial cell transforming squence 2), Tiam1 (T-cell lymphoma invasion and metastasis 1), Vav and P-Rex1/2 (PtdIns(3,4,5)P3 (phosphatidylinositol (3,4,5)-triphosphate)-dependent Rac exchanger).
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Affiliation(s)
- D R Cook
- Division of Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA
| | - K L Rossman
- 1] Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA [2] Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA
| | - C J Der
- 1] Division of Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA [2] Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA [3] Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA
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29
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Peviani M, Tortarolo M, Battaglia E, Piva R, Bendotti C. Specific induction of Akt3 in spinal cord motor neurons is neuroprotective in a mouse model of familial amyotrophic lateral sclerosis. Mol Neurobiol 2013; 49:136-48. [PMID: 23873136 DOI: 10.1007/s12035-013-8507-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 07/03/2013] [Indexed: 12/11/2022]
Abstract
Evidence is accumulating that an imbalance between pathways for degeneration or survival in motor neurons may play a central role in mechanisms that lead to neurodegeneration in amyotrophic lateral sclerosis (ALS). We and other groups have observed that downregulation, or lack of induction, of the PI3K/Akt prosurvival pathway may be responsible for defective response of motor neurons to injury and their consequent cellular demise. Some of the neuroprotective effects mediated by growth factors may involve activation of Akt, but a proof of concept of Akt as a target for therapy is lacking. We demonstrate that specific expression of constitutively activated Akt3 in motor neurons through the use of the promoter of homeobox gene Hb9 prevents neuronal loss induced by SOD1.G93A both in vitro (in mixed neuron/astrocyte cocultures) and in vivo (in a mouse model of ALS). Inhibition of ASK1 and GSK3beta was involved in the neuroprotective effects of activated Akt3, further supporting the hypothesis that induction of Akt3 may be a key step in activation of pathways for survival in the attempt to counteract motor neuronal degeneration in ALS.
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Affiliation(s)
- Marco Peviani
- Laboratory of Molecular Neurobiology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, via La Masa 19, 20156, Milan, Italy
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30
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DeGeer J, Lamarche-Vane N. Rho GTPases in neurodegeneration diseases. Exp Cell Res 2013; 319:2384-94. [PMID: 23830879 DOI: 10.1016/j.yexcr.2013.06.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 06/24/2013] [Indexed: 10/26/2022]
Abstract
Rho GTPases are molecular switches that modulate multiple intracellular signaling processes by means of various effector proteins. As a result, Rho GTPase activities are tightly spatiotemporally regulated in order to ensure homeostasis within the cell. Though the roles of Rho GTPases during neural development have been well documented, their participation during neurodegeneration has been far less characterized. Herein we discuss our current knowledge of the role and function of Rho GTPases and regulators during neurodegeneration, and highlight their potential as targets for therapeutic intervention in common neurodegenerative disorders.
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Affiliation(s)
- Jonathan DeGeer
- McGill University, Department of Anatomy and Cell Biology, Montreal, QC, Canada H3A 0C7
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31
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Zhang X, Hong YL, Xu DS, Feng Y, Zhao LJ, Ruan KF, Yang XJ. A Review of Experimental Research on Herbal Compounds in Amyotrophic Lateral Sclerosis. Phytother Res 2013; 28:9-21. [DOI: 10.1002/ptr.4960] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 01/05/2013] [Accepted: 02/04/2013] [Indexed: 01/05/2023]
Affiliation(s)
- Xue Zhang
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Engineering Research Center of Modern Preparation Technology of Zhangjiang; Shanghai China
| | - Yan-Long Hong
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Engineering Research Center of Modern Preparation Technology of Zhangjiang; Shanghai China
| | - De-Sheng Xu
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Shuguang Hospital; Shanghai University of Traditional Chinese Medicine; Shanghai China
| | - Yi Feng
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Engineering Research Center of Modern Preparation Technology of Zhangjiang; Shanghai China
| | - Li-Jie Zhao
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Engineering Research Center of Modern Preparation Technology of Zhangjiang; Shanghai China
| | - Ke-Feng Ruan
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Engineering Research Center of Modern Preparation Technology of Zhangjiang; Shanghai China
| | - Xiu-Juan Yang
- Engineering Research Center of Modern Preparation Technology of Traditional Chinese Medicine; Shanghai University of Traditional Chinese Medicine; Shanghai China
- Engineering Research Center of Modern Preparation Technology of Zhangjiang; Shanghai China
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32
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Posada-Duque RA, Velasquez-Carvajal D, Eckert GP, Cardona-Gomez GP. Atorvastatin requires geranylgeranyl transferase-I and Rac1 activation to exert neuronal protection and induce plasticity. Neurochem Int 2013; 62:433-45. [PMID: 23411415 DOI: 10.1016/j.neuint.2013.01.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 01/23/2013] [Accepted: 01/26/2013] [Indexed: 11/24/2022]
Abstract
Statins are widely used cholesterol-lowering drugs that may reduce the incidence of stroke and the progression of Alzheimer's disease (AD). However, how statins exert these beneficial effects remains poorly understood. Thus, this study evaluated the roles of Rac1 geranylgeranylation and the relationship between Rac1 and αN-catenin in the protective activity of atorvastatin (ATV) in a cortical neuronal culture model of glutamate (GLU) excitotoxicity. We found that ATV-induced neuroprotection and plasticity were blocked by isoprenoids, such as farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), inhibition of farnesylation (FTI-277) and geranylgeranylation (GGTI-286), down-regulation of GGTase-Iβ and Rac activity and promotion of active RhoA. Additionally, ATV rescued the distribution of dendritic αN-catenin and increased the number and length of dendritic branches; these effects were reversed by GGTI-286, GGTase-Iβ shRNA, Rac1 shRNA and a dominant-negative version of Rac1 (T17N). In summary, our findings suggest that ATV requires GGTase-Iβ, prenylation and active Rac1 to induce protection and plasticity. In this regard, αN-catenin is a marker for stable interactions between adhesion proteins and the actin cytoskeleton and is necessary for the neuroprotective action of ATV.
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Affiliation(s)
- Rafael Andrés Posada-Duque
- Cellular and Molecular Neurobiology Area, Group of Neuroscience of Antioquia, Faculty of Medicine, SIU, University of Antioquia, Medellín, Colombia
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33
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Furuta N, Makioka K, Fujita Y, Ikeda M, Takatama M, Matsuoka M, Okamoto K. Reduced expression of BTBD10 in anterior horn cells with
G
olgi fragmentation and
pTDP
‐43‐positive inclusions in patients with sporadic amyotrophic lateral sclerosis. Neuropathology 2013; 33:397-404. [DOI: 10.1111/neup.12010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 11/16/2012] [Accepted: 11/25/2012] [Indexed: 11/28/2022]
Affiliation(s)
- Natsumi Furuta
- Department of Neurology Gunma University Graduate School of Medicine
| | - Kouki Makioka
- Department of Neurology Gunma University Graduate School of Medicine
| | - Yukio Fujita
- Department of Neurology Gunma University Graduate School of Medicine
| | - Masaki Ikeda
- Department of Neurology Gunma University Graduate School of Medicine
| | - Masamitsu Takatama
- Department of Internal Medicine Geriatrics Research Institute and Hospital Gunma
| | | | - Koichi Okamoto
- Department of Neurology Gunma University Graduate School of Medicine
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34
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Reduced expression of BTBD10, an Akt activator, leads to motor neuron death. Cell Death Differ 2012; 19:1398-407. [PMID: 22388351 DOI: 10.1038/cdd.2012.19] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BTBD10, an Akt interactor, activates Akt by decreasing the protein phosphatase 2A-mediated dephosphorylation and inactivation of Akt. Overexpression of BTBD10 suppresses motor neuron death that is induced by a familial amyotrophic lateral sclerosis (ALS)-linked superoxide dismutase 1 (SOD1) mutant, G93A-SOD1 in vitro. In this study, we further investigated the BTBD10-mediated suppression of motor neuron death. We found that the small interfering RNA-mediated inhibition of BTBD10 expression led to the death of cultured motor neurons. In Caenorhabditis elegans (C. elegans), disruption of the btbd-10 gene caused not only loss of neurons, including both motor and touch-receptor neurons, but also a locomotion defect. In addition, we found that the expression of BTBD10 was generally decreased in the motor neurons from patients of sporadic ALS and transgenic mice overexpressing G93A-SOD1 (G93A-SOD1-transgenic mice). Collectively, these results suggest that the reduced expression of BTBD10 leads to motor neuron death both in vitro and in vivo.
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35
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Stankiewicz TR, Loucks FA, Schroeder EK, Nevalainen MT, Tyler KL, Aktories K, Bouchard RJ, Linseman DA. Signal transducer and activator of transcription-5 mediates neuronal apoptosis induced by inhibition of Rac GTPase activity. J Biol Chem 2012; 287:16835-48. [PMID: 22378792 DOI: 10.1074/jbc.m111.302166] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In several neuronal cell types, the small GTPase Rac is essential for survival. We have shown previously that the Rho family GTPase inhibitor Clostridium difficile toxin B (ToxB) induces apoptosis in primary rat cerebellar granule neurons (CGNs) principally via inhibition of Rac GTPase function. In the present study, incubation with ToxB activated a proapoptotic Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway, and a pan-JAK inhibitor protected CGNs from Rac inhibition. STAT1 expression was induced by ToxB; however, CGNs from STAT1 knock-out mice succumbed to ToxB-induced apoptosis as readily as wild-type CGNs. STAT3 displayed enhanced tyrosine phosphorylation following treatment with ToxB, and a reputed inhibitor of STAT3, cucurbitacin (JSI-124), reduced CGN apoptosis. Unexpectedly, JSI-124 failed to block STAT3 phosphorylation, and CGNs were not protected from ToxB by other known STAT3 inhibitors. In contrast, STAT5A tyrosine phosphorylation induced by ToxB was suppressed by JSI-124. In addition, roscovitine similarly inhibited STAT5A phosphorylation and protected CGNs from ToxB-induced apoptosis. Consistent with these results, adenoviral infection with a dominant negative STAT5 mutant, but not wild-type STAT5, significantly decreased ToxB-induced apoptosis of CGNs. Finally, chromatin immunoprecipitation with a STAT5 antibody revealed increased STAT5 binding to the promoter region of prosurvival Bcl-xL. STAT5 was recruited to the Bcl-xL promoter region in a ToxB-dependent manner, and this DNA binding preceded Bcl-xL down-regulation, suggesting transcriptional repression. These data indicate that a novel JAK/STAT5 proapoptotic pathway significantly contributes to neuronal apoptosis induced by the inhibition of Rac GTPase.
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Affiliation(s)
- Trisha R Stankiewicz
- Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado 80208, USA
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Enunlu I, Ozansoy M, Basak AN. Alfa-class prefoldin protein UXT is a novel interacting partner of Amyotrophic Lateral Sclerosis 2 (Als2) protein. Biochem Biophys Res Commun 2011; 413:471-5. [PMID: 21907703 DOI: 10.1016/j.bbrc.2011.08.121] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 08/26/2011] [Indexed: 12/11/2022]
Abstract
Mutations in Als2 gene cause several autosomal recessive forms of motor neuron diseases including Juvenile Amyotrophic Lateral Sclerosis (JALS), Juvenile Primary Lateral Sclerosis (PLSJ) and Infantile-onset Ascending Hereditary Spastic Paralysis (IAHSP). To find novel protein-protein interactions of Als2 protein we performed a yeast two hybrid screen and fished out the Ubiquitously Expressed Transcript (UXT) protein. UXT is a novel gene encoding for an α-class prefoldin type chaperone which acts as a co-activator for various transcriptional factors such as Nf-κB and AR. The interaction between Als2 and UXT was confirmed by co-immunoprecipitation. Co-localization between endogenous Als2 and UXT was mainly found in the cytoplasm of neuronal Neuro2a cells with immunofluorescence microscopy. Cell cycle arrest of Neuro2a cells showed that Als2 and Uxt transcriptional levels are synchronously changing. Our results suggest that Als2 is a binding partner of Uxt and Als2/Uxt interaction could be important for the activation of Nf-κB pathway. These results provides basis for future research to investigate the role of Nf-κB pathway in the development of motor neuron diseases.
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Affiliation(s)
- Izzet Enunlu
- Department of Molecular Biology and Genetics, Boğaziçi University, Istanbul, Turkey.
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Pesaresi MG, Amori I, Giorgi C, Ferri A, Fiorenzo P, Gabanella F, Salvatore AM, Giorgio M, Pelicci PG, Pinton P, Carrì MT, Cozzolino M. Mitochondrial redox signalling by p66Shc mediates ALS-like disease through Rac1 inactivation. Hum Mol Genet 2011; 20:4196-208. [PMID: 21828072 DOI: 10.1093/hmg/ddr347] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Increased oxidative stress and mitochondrial damage are among the mechanisms whereby mutant SOD1 (mutSOD1) associated with familial forms of amyotrophic lateral sclerosis (ALS) induces motoneuronal death. The 66 kDa isoform of the growth factor adapter Shc (p66Shc) is known to be central in the control of mitochondria-dependent oxidative balance. Here we report that expression of mutSOD1s induces the activation of p66Shc in neuronal cells and that the overexpression of inactive p66Shc mutants protects cells from mutSOD1-induced mitochondrial damage. Most importantly, deletion of p66Shc ameliorates mitochondrial function, delays onset, improves motor performance and prolongs survival in transgenic mice modelling ALS. We also show that p66Shc activation by mutSOD1 causes a strong decrease in the activity of the small GTPase Rac1 through a redox-sensitive regulation. Our results provide new insight into the potential mechanisms of mutSOD1-mediated mitochondrial dysfunction.
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Kirby J, Ning K, Ferraiuolo L, Heath PR, Ismail A, Kuo SW, Valori CF, Cox L, Sharrack B, Wharton SB, Ince PG, Shaw PJ, Azzouz M. Phosphatase and tensin homologue/protein kinase B pathway linked to motor neuron survival in human superoxide dismutase 1-related amyotrophic lateral sclerosis. ACTA ACUST UNITED AC 2011; 134:506-17. [PMID: 21228060 PMCID: PMC3030763 DOI: 10.1093/brain/awq345] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Gene expression profiling has been used previously with spinal cord homogenates and laser capture microdissected motor neurons to determine the mechanisms involved in neurodegeneration in amyotrophic lateral sclerosis. However, while cellular and animal model work has focused on superoxide dismutase 1-related amyotrophic lateral sclerosis, the transcriptional profile of human mutant superoxide dismutase 1 motor neurons has remained undiscovered. The aim of this study was to apply gene expression profiling to laser captured motor neurons from human superoxide dismutase 1-related amyotrophic lateral sclerosis and neurologically normal control cases, in order to determine those pathways dysregulated in human superoxide dismutase 1-related neurodegeneration and to establish potential pathways suitable for therapeutic intervention. Identified targets were then validated in cultured cell models using lentiviral vectors to manipulate the expression of key genes. Microarray analysis identified 1170 differentially expressed genes in spinal cord motor neurons from superoxide dismutase 1-related amyotrophic lateral sclerosis, compared with controls. These genes encoded for proteins in multiple functional categories, including those involved in cell survival and cell death. Further analysis determined that multiple genes involved in the phosphatidylinositol-3 kinase signalling cascade were differentially expressed in motor neurons that survived the disease process. Functional experiments in cultured cells and primary motor neurons demonstrate that manipulating this pathway by reducing the expression of a single upstream target, the negative phosphatidylinositol-3 kinase regulator phosphatase and tensin homology, promotes a marked pro-survival effect. Therefore, these data indicate that proteins in the phosphatidylinositol-3 kinase pathway could represent a target for therapeutic manipulation in motor neuron degeneration.
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Affiliation(s)
- Janine Kirby
- Academic Neurology Unit, Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK.
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Loss of ALS2/Alsin exacerbates motor dysfunction in a SOD1-expressing mouse ALS model by disturbing endolysosomal trafficking. PLoS One 2010; 5:e9805. [PMID: 20339559 PMCID: PMC2842444 DOI: 10.1371/journal.pone.0009805] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 03/03/2010] [Indexed: 12/11/2022] Open
Abstract
Background ALS2/alsin is a guanine nucleotide exchange factor for the small GTPase Rab5 and involved in macropinocytosis-associated endosome fusion and trafficking, and neurite outgrowth. ALS2 deficiency accounts for a number of juvenile recessive motor neuron diseases (MNDs). Recently, it has been shown that ALS2 plays a role in neuroprotection against MND-associated pathological insults, such as toxicity induced by mutant Cu/Zn superoxide dismutase (SOD1). However, molecular mechanisms underlying the relationship between ALS2-associated cellular function and its neuroprotective role remain unclear. Methodology/Principal Findings To address this issue, we investigated the molecular and pathological basis for the phenotypic modification of mutant SOD1-expressing mice by ALS2 loss. Genetic ablation of Als2 in SOD1H46R, but not SOD1G93A, transgenic mice aggravated the mutant SOD1-associated disease symptoms such as body weight loss and motor dysfunction, leading to the earlier death. Light and electron microscopic examinations revealed the presence of degenerating and/or swollen spinal axons accumulating granular aggregates and autophagosome-like vesicles in early- and even pre-symptomatic SOD1H46R mice. Further, enhanced accumulation of insoluble high molecular weight SOD1, poly-ubiquitinated proteins, and macroautophagy-associated proteins such as polyubiquitin-binding protein p62/SQSTM1 and a lipidated form of light chain 3 (LC3-II), emerged in ALS2-deficient SOD1H46R mice. Intriguingly, ALS2 was colocalized with LC3 and p62, and partly with SOD1 on autophagosome/endosome hybrid compartments, and loss of ALS2 significantly lowered the lysosome-dependent clearance of LC3 and p62 in cultured cells. Conclusions/Significance Based on these observations, although molecular basis for the distinctive susceptibilities to ALS2 loss in different mutant SOD1-expressing ALS models is still elusive, disturbance of the endolysosomal system by ALS2 loss may exacerbate the SOD1H46R-mediated neurotoxicity by accelerating the accumulation of immature vesicles and misfolded proteins in the spinal cord. We propose that ALS2 is implicated in endolysosomal trafficking through the fusion between endosomes and autophagosomes, thereby regulating endolysosomal protein degradation in vivo.
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Won Kim J, Nie B, Sahm H, Brown DPG, Tegeler T, You JS, Wang M. Targeted quantitative analysis of superoxide dismutase 1 in cisplatin-sensitive and cisplatin-resistant human ovarian cancer cells. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:700-4. [PMID: 20117967 PMCID: PMC2827867 DOI: 10.1016/j.jchromb.2010.01.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 01/04/2010] [Accepted: 01/11/2010] [Indexed: 11/20/2022]
Abstract
Protein quantification in a complex protein mixture presents a daunting task in biochemical analysis. Antibody-based immunoassays are traditional methods for protein quantification. However, there are issues associated with accuracy and specificity in these assays, especially when the changes are small (e.g., <2-fold). With recent developments in mass spectrometry, monitoring a selected peptide, thus protein, in a complex biological sample has become possible. In this study, we demonstrate a simple mass spectrometry-based method for selective measurement of a moderately low abundant protein, superoxide dismutase 1 (SOD1), in cisplatin-sensitive and cisplatin-resistant human ovarian cancer cells. Selected-reaction-monitoring (SRM) technology was employed to specifically analyze the target peptides in a pair of human ovarian cancer cell lines: 2008/2008-C13*5.25 (cisplatin-sensitive/cisplatin-resistant, respectively). The observed 1.47-fold higher expression in the resistant cell line is consistent with findings by other approaches. This robust liquid chromatography/mass spectrometry (LC/MS) method provides a powerful tool for targeted proteomic verification and/or validation studies.
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Affiliation(s)
- Jong Won Kim
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
| | - Bei Nie
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
| | - Heather Sahm
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
| | - Dawn P. G. Brown
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
| | - Tony Tegeler
- Monarch LifeSciences, LLC., Indianapolis, Indiana 46202, USA
| | - Jin-Sam You
- Monarch LifeSciences, LLC., Indianapolis, Indiana 46202, USA
| | - Mu Wang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
- Monarch LifeSciences, LLC., Indianapolis, Indiana 46202, USA
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Ryan CL, Baranowski DC, Chitramuthu BP, Malik S, Li Z, Cao M, Minotti S, Durham HD, Kay DG, Shaw CA, Bennett HPJ, Bateman A. Progranulin is expressed within motor neurons and promotes neuronal cell survival. BMC Neurosci 2009; 10:130. [PMID: 19860916 PMCID: PMC2779192 DOI: 10.1186/1471-2202-10-130] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Accepted: 10/27/2009] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Progranulin is a secreted high molecular weight growth factor bearing seven and one half copies of the cysteine-rich granulin-epithelin motif. While inappropriate over-expression of the progranulin gene has been associated with many cancers, haploinsufficiency leads to atrophy of the frontotemporal lobes and development of a form of dementia (frontotemporal lobar degeneration with ubiquitin positive inclusions, FTLD-U) associated with the formation of ubiquitinated inclusions. Recent reports indicate that progranulin has neurotrophic effects, which, if confirmed would make progranulin the only neuroprotective growth factor that has been associated genetically with a neurological disease in humans. Preliminary studies indicated high progranulin gene expression in spinal cord motor neurons. However, it is uncertain what the role of Progranulin is in normal or diseased motor neuron function. We have investigated progranulin gene expression and subcellular localization in cultured mouse embryonic motor neurons and examined the effect of progranulin over-expression and knockdown in the NSC-34 immortalized motor neuron cell line upon proliferation and survival. RESULTS In situ hybridisation and immunohistochemical techniques revealed that the progranulin gene is highly expressed by motor neurons within the mouse spinal cord and in primary cultures of dissociated mouse embryonic spinal cord-dorsal root ganglia. Confocal microscopy coupled to immunocytochemistry together with the use of a progranulin-green fluorescent protein fusion construct revealed progranulin to be located within compartments of the secretory pathway including the Golgi apparatus. Stable transfection of the human progranulin gene into the NSC-34 motor neuron cell line stimulates the appearance of dendritic structures and provides sufficient trophic stimulus to survive serum deprivation for long periods (up to two months). This is mediated at least in part through an anti-apoptotic mechanism. Control cells, while expressing basal levels of progranulin do not survive in serum free conditions. Knockdown of progranulin expression using shRNA technology further reduced cell survival. CONCLUSION Neurons are among the most long-lived cells in the body and are subject to low levels of toxic challenges throughout life. We have demonstrated that progranulin is abundantly expressed in motor neurons and is cytoprotective over prolonged periods when over-expressed in a neuronal cell line. This work highlights the importance of progranulin as neuroprotective growth factor and may represent a therapeutic target for neurodegenerative diseases including motor neuron disease.
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Affiliation(s)
- Cara L Ryan
- Royal Victoria Hospital and Department of Medicine, McGill University Health Centre Research Institute, Montreal, Quebec, Canada.
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Hashimoto Y, Kurita M, Aiso S, Nishimoto I, Matsuoka M. Humanin inhibits neuronal cell death by interacting with a cytokine receptor complex or complexes involving CNTF receptor alpha/WSX-1/gp130. Mol Biol Cell 2009; 20:2864-73. [PMID: 19386761 DOI: 10.1091/mbc.e09-02-0168] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Humanin (HN) inhibits neuronal death induced by various Alzheimer's disease (AD)-related insults via an unknown receptor on cell membranes. Our earlier study indicated that the activation of STAT3 was essential for HN-induced neuroprotection, suggesting that the HN receptor may belong to the cytokine receptor family. In this study, a series of loss-of-function tests indicated that gp130, the common subunit of receptors belonging to the IL-6 receptor family, was essential for HN-induced neuroprotection. Overexpression of ciliary neurotrophic factor receptor alpha (CNTFR) and/or the IL-27 receptor subunit, WSX-1, but not that of any other tested gp130-related receptor subunit, up-regulated HN binding to neuronal cells, whereas siRNA-mediated knockdown of endogenous CNTFR and/or WSX-1 reduced it. These results suggest that both CNTFR and WSX-1 may be also involved in HN binding to cells. Consistent with these results, loss-of-functions of CNTFR or WSX-1 in neuronal cells nullified their responsiveness to HN-mediated protection. In vitro-reconstituted binding assays showed that HN, but not the other control peptide, induced the hetero-oligomerization of CNTFR, WSX-1, and gp130. Together, these results indicate that HN protects neurons by binding to a complex or complexes involving CNTFR/WSX-1/gp130.
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Affiliation(s)
- Yuichi Hashimoto
- Department of Pharmacology and Neuroscience, Tokyo Medical University, Shinjuku-ku, Tokyo 160-8402, Japan
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Jacquier A, Bellouze S, Blanchard S, Bohl D, Haase G. Astrocytic protection of spinal motor neurons but not cortical neurons against loss of Als2/alsin function. Hum Mol Genet 2009; 18:2127-39. [PMID: 19304783 DOI: 10.1093/hmg/ddp136] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Three neurodegenerative diseases affecting upper and/or lower motor neurons have been associated with loss of ALS2/Alsin function: juvenile amyotrophic lateral sclerosis, primary lateral sclerosis and infantile-onset ascending hereditary spastic paralysis. The distinct neuronal vulnerability and the role of glia in these diseases remains, however, unclear. We here demonstrate that alsin-depleted spinal motor neurons can be rescued from defective survival and axon growth by co-cultured astrocytes. The astrocytic rescue is mediated by a soluble protective factor rather than by cellular contact. Cortical neurons are intrinsically as vulnerable to alsin depletion as spinal motor neurons but cannot be rescued by co-cultured astrocytes. To our knowledge, these data provide the first example of non-cell-autonomous glial effects in a recessive form of motor neuron disease and a potential rationale for the higher vulnerability of upper versus lower motor neurons in ALS2/Alsin-linked disorders.
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Affiliation(s)
- A Jacquier
- Laboratory of Motor Neuron Disease Modeling and Therapy, Institut de Biologie du Développement de Marseille Luminy, Université Aix-Marseille, Case 907, Parc scientifique de Luminy, F-13273 Marseille cedex 09, France
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Soares DC, Barlow PN, Porteous DJ, Devon RS. An interrupted beta-propeller and protein disorder: structural bioinformatics insights into the N-terminus of alsin. J Mol Model 2008; 15:113-22. [PMID: 19023603 DOI: 10.1007/s00894-008-0381-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Accepted: 11/05/2008] [Indexed: 12/11/2022]
Abstract
Defects in the human ALS2 gene, which encodes the 1,657-amino-acid residue protein alsin, are linked to several related motor neuron diseases. We created a structural model for the N-terminal 690-residue region of alsin through comparative modelling based on regulator of chromosome condensation 1 (RCC1). We propose that this alsin region contains seven RCC1-like repeats in a seven-bladed beta-propeller structure. The propeller is formed by a double clasp arrangement containing two segments (residues 1-218 and residues 525-690). The 306-residue insert region, predicted to lie within blade 5 and to be largely disordered, is poorly conserved across species. Surface patches of evolutionary conservation probably indicate locations of binding sites. Both disease-causing missense mutations-Cys157Tyr and Gly540Glu-are buried in the propeller and likely to be structurally disruptive. This study aids design of experimental studies by highlighting the importance of construct length, will enhance interpretation of protein-protein interactions, and enable rational site-directed mutagenesis.
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Affiliation(s)
- Dinesh C Soares
- Medical Genetics Section, Molecular Medicine Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh EH42XU, UK.
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Zhang F, Zheng W, Pi R, Mei Z, Bao Y, Gao J, Tang W, Chen S, Liu P. Cryptotanshinone protects primary rat cortical neurons from glutamate-induced neurotoxicity via the activation of the phosphatidylinositol 3-kinase/Akt signaling pathway. Exp Brain Res 2008; 193:109-18. [DOI: 10.1007/s00221-008-1600-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 09/26/2008] [Indexed: 11/28/2022]
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Cai H, Shim H, Lai C, Xie C, Lin X, Yang WJ, Chandran J. ALS2/alsin knockout mice and motor neuron diseases. NEURODEGENER DIS 2008; 5:359-66. [PMID: 18714162 DOI: 10.1159/000151295] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Accepted: 12/21/2007] [Indexed: 12/11/2022] Open
Abstract
Autosomal recessive mutations in the ALS2 gene have been linked to juvenile-onset amyotrophic lateral sclerosis (ALS2), primary lateral sclerosis and juvenile-onset ascending hereditary spastic paraplegia. Except for two recently identified missense mutations, all other mutations in the ALS2 gene lead to a premature stop codon and likely abrogate all the potential functions of alsin, the protein encoded by the ALS2 gene. To study the pathologic mechanisms of ALS2 deficiency, four different lines of ALS2 knockout (ALS2(-/-)) mice have been generated by independent groups. The loss of ALS2/alsin does not have a drastic effect on the survival or function of motor neurons in mice. However, subtle deficits observed in the behavior and pathology of these mice have aided in our understanding of the relationship between alsin and motor neuron dysfunction. In this review, we summarize and reconcile major findings of ALS2(-/-) mice and attempt to place these results within the larger context of modeling recessive movement disorders in mice.
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Affiliation(s)
- Huaibin Cai
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892-3707, USA.
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Hadjebi O, Casas-Terradellas E, Garcia-Gonzalo FR, Rosa JL. The RCC1 superfamily: From genes, to function, to disease. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1783:1467-79. [DOI: 10.1016/j.bbamcr.2008.03.015] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 03/19/2008] [Accepted: 03/20/2008] [Indexed: 02/07/2023]
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Active N-Ras and B-Raf inhibit anoikis by downregulating Bim expression in melanocytic cells. J Invest Dermatol 2008; 129:432-7. [PMID: 18668139 DOI: 10.1038/jid.2008.227] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
B-Raf and N-Ras proteins are often activated in melanoma, yet their roles in producing inherent survival signals are not fully understood. In this study, we investigated how N-RAS(Q61K) and B-RAF(V600E) contribute to melanoma's resistance to apoptosis induced by detachment from the extracellular matrix (anoikis). We found that expression of constitutively active N-RAS(Q61K) and B-RAF(V600E) downregulated the proapoptotic Bim protein in an immortalized melanocyte cell line. Bim is one of the main proapoptotic mediators of anoikis. Western blot analysis showed that detachment increased Bim expression in melanocytes, and Annexin V staining indicated that detachment induced cell death significantly in melanocytes. Blocking Bim expression by using RNAi vectors or by expressing N-RAS(Q61K) significantly inhibited anoikis in melanocytes. In summary, this report indicates that N-RAS(Q61K) and B-RAF(V600E) contribute to melanoma's resistance to apoptosis in part by downregulating Bim expression, suggesting that Bim is a possible treatment target for overriding melanoma's inherent defenses against cell death.
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P-Rex2 regulates Purkinje cell dendrite morphology and motor coordination. Proc Natl Acad Sci U S A 2008; 105:4483-8. [PMID: 18334636 DOI: 10.1073/pnas.0712324105] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The small GTPase Rac controls cell morphology, gene expression, and reactive oxygen species formation. Manipulations of Rac activity levels in the cerebellum result in motor coordination defects, but activators of Rac in the cerebellum are unknown. P-Rex family guanine-nucleotide exchange factors activate Rac. We show here that, whereas P-Rex1 expression within the brain is widespread, P-Rex2 is specifically expressed in the Purkinje neurons of the cerebellum. We have generated P-Rex2(-/-) and P-Rex1(-/-)/P-Rex2(-/-) mice, analyzed their Purkinje cell morphology, and assessed their motor functions in behavior tests. The main dendrite is thinned in Purkinje cells of P-Rex2(-/-) pups and dendrite structure appears disordered in Purkinje cells of adult P-Rex2(-/-) and P-Rex1(-/-)/P-Rex2(-/-) mice. P-Rex2(-/-) mice show a mild motor coordination defect that progressively worsens with age and is more pronounced in females than in males. P-Rex1(-/-)/P-Rex2(-/-) mice are ataxic, with reduced basic motor activity and abnormal posture and gait, as well as impaired motor coordination even at a young age. We conclude that P-Rex1 and P-Rex2 are important regulators of Purkinje cell morphology and cerebellar function.
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50
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de Curtis I. Functions of Rac GTPases during neuronal development. Dev Neurosci 2008; 30:47-58. [PMID: 18075254 DOI: 10.1159/000109851] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Accepted: 02/27/2007] [Indexed: 12/11/2022] Open
Abstract
The small GTPases of the Rho family are important regulators of the actin cytoskeleton and are critical for several aspects of neuronal development including the establishment of neuronal polarity, extension of axon and dendrites, neurite branching, axonal navigation and synapse formation. The aim of this review is to present evidence supporting the function of Rac and Rac-related proteins in different aspects of neuronal maturation, based on work performed with organisms including nematodes, Drosophila, Xenopus and mice, and with primary cultures of developing neurons. Three of the 4 vertebrate Rac-related genes, namely Rac1, Rac3 and RhoG, are expressed in the nervous system, and several data support an essential role of all 3 GTPases in distinct aspects of neuronal development and function. Two important points emerge from the analysis presented: highly homologous Rac-related proteins may perform different functions in the developing nervous system; on the other hand, the data also indicate that similar GTPases may perform redundant functions in vivo.
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Affiliation(s)
- Ivan de Curtis
- Cell Adhesion Unit, San Raffaele Scientific Institute, Milan, Italy.
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