301
|
Soo KY, Atkin JD. Autophagy dysregulation by mutant fused in sarcoma--implications for amyotrophic lateral sclerosis. Cell Death Dis 2015; 6:e1945. [PMID: 26512956 PMCID: PMC4632325 DOI: 10.1038/cddis.2015.311] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- K Y Soo
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia
| | - J D Atkin
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, North Ryde, New South Wales, Australia
| |
Collapse
|
302
|
Haston KM, Finkbeiner S. Clinical Trials in a Dish: The Potential of Pluripotent Stem Cells to Develop Therapies for Neurodegenerative Diseases. Annu Rev Pharmacol Toxicol 2015; 56:489-510. [PMID: 26514199 PMCID: PMC4868344 DOI: 10.1146/annurev-pharmtox-010715-103548] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurodegenerative diseases are a leading cause of death. No disease-modifying therapies are available, and preclinical animal model data have routinely failed to translate into success for therapeutics. Induced pluripotent stem cell (iPSC) biology holds great promise for human in vitro disease modeling because these cells can give rise to any cell in the human brain and display phenotypes specific to neurodegenerative diseases previously identified in postmortem and clinical samples. Here, we explore the potential and caveats of iPSC technology as a platform for drug development and screening, and the future potential to use large cohorts of disease-bearing iPSCs to perform clinical trials in a dish.
Collapse
Affiliation(s)
- Kelly M Haston
- Gladstone Institute of Neurological Disease, San Francisco, California 94158;
| | - Steven Finkbeiner
- Gladstone Institute of Neurological Disease, San Francisco, California 94158;
- Taube/Koret Center for Neurodegenerative Disease and the Hellman Family Foundation Program in Alzheimer's Disease Research, San Francisco, California 94158
- Departments of Neurology and Physiology, University of California, San Francisco, California 94143
| |
Collapse
|
303
|
Moruno Manchon JF, Uzor NE, Dabaghian Y, Furr-Stimming EE, Finkbeiner S, Tsvetkov AS. Cytoplasmic sphingosine-1-phosphate pathway modulates neuronal autophagy. Sci Rep 2015; 5:15213. [PMID: 26477494 PMCID: PMC4609990 DOI: 10.1038/srep15213] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/21/2015] [Indexed: 12/13/2022] Open
Abstract
Autophagy is an important homeostatic mechanism that eliminates long-lived proteins, protein aggregates and damaged organelles. Its dysregulation is involved in many neurodegenerative disorders. Autophagy is therefore a promising target for blunting neurodegeneration. We searched for novel autophagic pathways in primary neurons and identified the cytosolic sphingosine-1-phosphate (S1P) pathway as a regulator of neuronal autophagy. S1P, a bioactive lipid generated by sphingosine kinase 1 (SK1) in the cytoplasm, is implicated in cell survival. We found that SK1 enhances flux through autophagy and that S1P-metabolizing enzymes decrease this flux. When autophagy is stimulated, SK1 relocalizes to endosomes/autophagosomes in neurons. Expression of a dominant-negative form of SK1 inhibits autophagosome synthesis. In a neuron model of Huntington’s disease, pharmacologically inhibiting S1P-lyase protected neurons from mutant huntingtin-induced neurotoxicity. These results identify the S1P pathway as a novel regulator of neuronal autophagy and provide a new target for developing therapies for neurodegenerative disorders.
Collapse
Affiliation(s)
| | - Ndidi-Ese Uzor
- Department of Neurobiology and Anatomy, University of Texas Medical School, Houston, TX 77030.,The University of Texas Graduate School of Biomedical Sciences, Houston, TX 77030
| | - Yuri Dabaghian
- The Jan and Dan Duncan Neurological Research Institute, Baylor College of Medicine, Houston, TX 77030.,Department of Computational and Applied Mathematics, Rice University, Houston, TX 77005
| | | | - Steven Finkbeiner
- Gladstone Institute of Neurological Disease and the Taube/Koret Center for Neurodegenerative Disease Research, San Francisco, CA 94158.,Departments of Neurology and Physiology, University of California, San Francisco, CA 94143
| | - Andrey S Tsvetkov
- Department of Neurobiology and Anatomy, University of Texas Medical School, Houston, TX 77030.,The University of Texas Graduate School of Biomedical Sciences, Houston, TX 77030
| |
Collapse
|
304
|
Biasiotto G, Di Lorenzo D, Archetti S, Zanella I. Iron and Neurodegeneration: Is Ferritinophagy the Link? Mol Neurobiol 2015; 53:5542-74. [PMID: 26468157 DOI: 10.1007/s12035-015-9473-y] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/01/2015] [Indexed: 12/12/2022]
Abstract
Mounting evidence indicates that the lysosome-autophagy pathway plays a critical role in iron release from ferritin, the main iron storage cellular protein, hence in the distribution of iron to the cells. The recent identification of nuclear receptor co-activator 4 as the receptor for ferritin delivery to selective autophagy sheds further light on the understanding of the mechanisms underlying this pathway. The emerging view is that iron release from ferritin through the lysosomes is a general mechanism in normal and tumour cells of different tissue origins, but it has not yet been investigated in brain cells. Defects in the lysosome-autophagy pathway are often involved in the pathogenesis of neurodegenerative disorders, and brain iron homeostasis disruption is a hallmark of many of these diseases. However, in most cases, it has not been established whether iron dysregulation is directly involved in the pathogenesis of the diseases or if it is a secondary effect derived from other pathogenic mechanisms. The recent evidence of the crucial involvement of autophagy in cellular iron handling offers new perspectives about the role of iron in neurodegeneration, suggesting that autophagy dysregulation could cause iron dyshomeostasis. In this review, we recapitulate our current knowledge on the routes through which iron is released from ferritin, focusing on the most recent advances. We summarise the current evidence concerning lysosome-autophagy pathway dysfunctions and those of iron metabolism and discuss their potential interconnections in several neurodegenerative disorders, such as Alzheimer's, Parkinson's and Huntington's diseases; amyotrophic lateral sclerosis; and frontotemporal lobar dementia.
Collapse
Affiliation(s)
- Giorgio Biasiotto
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy
- Biotechnology Laboratory, Department of Diagnostics, Civic Hospital of Brescia, Piazzale Spedali Civili 1, 25123, Brescia, Italy
| | - Diego Di Lorenzo
- Biotechnology Laboratory, Department of Diagnostics, Civic Hospital of Brescia, Piazzale Spedali Civili 1, 25123, Brescia, Italy
| | - Silvana Archetti
- Biotechnology Laboratory, Department of Diagnostics, Civic Hospital of Brescia, Piazzale Spedali Civili 1, 25123, Brescia, Italy
| | - Isabella Zanella
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
- Biotechnology Laboratory, Department of Diagnostics, Civic Hospital of Brescia, Piazzale Spedali Civili 1, 25123, Brescia, Italy.
| |
Collapse
|
305
|
Roos A, Kollipara L, Buchkremer S, Labisch T, Brauers E, Gatz C, Lentz C, Gerardo-Nava J, Weis J, Zahedi RP. Cellular Signature of SIL1 Depletion: Disease Pathogenesis due to Alterations in Protein Composition Beyond the ER Machinery. Mol Neurobiol 2015; 53:5527-41. [PMID: 26468156 DOI: 10.1007/s12035-015-9456-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 09/25/2015] [Indexed: 12/14/2022]
Abstract
SIL1 acts as nucleotide exchange factor for the endoplasmic reticulum chaperone BiP. Mutations of SIL1 cause Marinesco-Sjögren syndrome (MSS), a neurodegenerative disorder. Moreover, a particular function of SIL1 for etiopathology of amyotrophic lateral sclerosis (ALS) was highlighted, thus declaring the functional SIL1-BiP complex as a modifier for neurodegenerative disorders. Thereby, depletion of SIL1 was associated with an earlier manifestation and in strengthened disease progression in ALS. Owing to the absence of appropriate in vitro models, the precise cellular pathophysiological mechanisms leading to neurodegeneration in MSS and triggering the same in further disorders like ALS are still elusive. We found that SIL1 depletion in human embryonic kidney 293 (HEK293) cells led to structural changes of the endoplasmic reticulum (ER) including the nuclear envelope and mitochondrial degeneration that closely mimic pathological alterations in MSS and ALS. Functional studies revealed disturbed protein transport, cytotoxicity with reduced proliferation and viability, accompanied by activation of cellular defense mechanisms including the unfolded protein response, ER-associated degradation pathway, proteolysis, and expression of apoptotic and survival factors. Our data moreover indicated that proteins involved in cytoskeletal organization, vesicular transport, mitochondrial function, and neurological processes contribute to SIL1 pathophysiology. Altered protein expression upon SIL1 depletion in vitro could be confirmed in Sil1-deficient motoneurones for paradigmatic proteins belonging to different functional classes. Our results demonstrate that SIL1-depleted HEK293 cells are an appropriate model to identify proteins modulated by SIL1 expression level and contributing to neurodegeneration in MSS and further disorders like ALS. Thereby, our combined results point out that proteins beyond such involved ER-related protein processing are affected by SIL1 depletion.
Collapse
Affiliation(s)
- Andreas Roos
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany.
- Leibniz-Institut für Analytische Wissenschaften-ISAS e.V, Otto-Hahn-Str. 6b, 44227, Dortmund, Germany.
| | - Laxmikanth Kollipara
- Leibniz-Institut für Analytische Wissenschaften-ISAS e.V, Otto-Hahn-Str. 6b, 44227, Dortmund, Germany
| | - Stephan Buchkremer
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Thomas Labisch
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Eva Brauers
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Christian Gatz
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Chris Lentz
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - José Gerardo-Nava
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Joachim Weis
- Institute of Neuropathology, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany
| | - René P Zahedi
- Leibniz-Institut für Analytische Wissenschaften-ISAS e.V, Otto-Hahn-Str. 6b, 44227, Dortmund, Germany
| |
Collapse
|
306
|
Cheng CW, Lin MJ, Shen CKJ. Rapamycin alleviates pathogenesis of a newDrosophilamodel of ALS-TDP. J Neurogenet 2015. [DOI: 10.3109/01677063.2015.1077832] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
307
|
The Progranulin Cleavage Products, Granulins, Exacerbate TDP-43 Toxicity and Increase TDP-43 Levels. J Neurosci 2015; 35:9315-28. [PMID: 26109656 DOI: 10.1523/jneurosci.4808-14.2015] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mutations in the human progranulin gene resulting in protein haploinsufficiency cause frontotemporal lobar degeneration with TDP-43 inclusions. Although progress has been made in understanding the normal functions of progranulin and TDP-43, the molecular interactions between these proteins remain unclear. Progranulin is proteolytically processed into granulins, but the role of granulins in the pathogenesis of neurodegenerative disease is unknown. We used a Caenorhabditis elegans model of neuronal TDP-43 proteinopathy to specifically interrogate the contribution of granulins to the neurodegenerative process. Complete loss of the progranulin gene did not worsen TDP-43 toxicity, whereas progranulin heterozygosity did. Interestingly, expression of individual granulins alone had little effect on behavior. In contrast, when granulins were coexpressed with TDP-43, they exacerbated its toxicity in a variety of behaviors including motor coordination. These same granulins increased TDP-43 levels via a post-translational mechanism. We further found that in human neurodegenerative disease subjects, granulin fragments accumulated specifically in diseased regions of brain. To our knowledge, this is the first demonstration of a toxic role for granulin fragments in a neurodegenerative disease model. These studies suggest that presence of cleaved granulins, rather than or in addition to loss of full-length progranulin, may contribute to disease in TDP-43 proteinopathies.
Collapse
|
308
|
Wang G, Yang H, Yan S, Wang CE, Liu X, Zhao B, Ouyang Z, Yin P, Liu Z, Zhao Y, Liu T, Fan N, Guo L, Li S, Li XJ, Lai L. Cytoplasmic mislocalization of RNA splicing factors and aberrant neuronal gene splicing in TDP-43 transgenic pig brain. Mol Neurodegener 2015; 10:42. [PMID: 26334913 PMCID: PMC4557629 DOI: 10.1186/s13024-015-0036-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Accepted: 08/10/2015] [Indexed: 12/13/2022] Open
Abstract
Background TAR DNA-binding protein 43 (TDP-43) is a nuclear protein, but it is redistributed in the neuronal cytoplasm in both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Because small transgenic animal models often lack cytoplasmic TDP-43, how the cytoplasmic accumulation of TDP-43 contributes to these diseases remains unclear. The current study is aimed at studying the mechanism of cytoplasmic pathology of TDP-43. Results We established transgenic pigs expressing mutant TDP-43 (M337V). This pig model shows severe phenotypes and early death. We found that transgenic TDP-43 is also distributed in the cytoplasm of neuronal cells in the spinal cord and brain. Transgenic TDP-43 interacts with PSF, an RNA splicing factor that associates with NeuN to regulate neuronal RNA splicing. The interaction of TDP-43, PSF and NeuN causes PSF and NeuN mislocalize into the neuronal cytoplasm in transgenic pigs. Consistently, abnormal PSF-related neuronal RNA splicing is seen in TDP-43 transgenic pigs. The cytoplasmic localization of PSF and NeuN as well as abnormal PSF-related neuronal RNA splicing was also found in ALS patient brains. Conclusion Our findings from a large mammalian model suggest that cytoplasmic mutant TDP-43 could reduce the nuclear function of RNA splicing factors, contributing to neuropathology.
Collapse
Affiliation(s)
- Guohao Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Huaqiang Yang
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Sen Yan
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Chuan-En Wang
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Xudong Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Bentian Zhao
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Zhen Ouyang
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Peng Yin
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Zhaoming Liu
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Yu Zhao
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Tao Liu
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Nana Fan
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Lin Guo
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| | - Shihua Li
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Xiao-Jiang Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Liangxue Lai
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| |
Collapse
|
309
|
Donnelly CJ, Grima JC, Sattler R. Aberrant RNA homeostasis in amyotrophic lateral sclerosis: potential for new therapeutic targets? Neurodegener Dis Manag 2015; 4:417-37. [PMID: 25531686 DOI: 10.2217/nmt.14.36] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive motor neuron degeneration. The disease pathogenesis is multifaceted in that multiple cellular and molecular pathways have been identified as contributors to the disease progression. Consequently, numerous therapeutic targets have been pursued for clinical development, unfortunately with little success. The recent discovery of mutations in RNA modulating genes such as TARDBP/TDP-43, FUS/TLS or C9ORF72 changed our understanding of neurodegenerative mechanisms in ALS and introduced the role of dysfunctional RNA processing as a significant contributor to disease pathogenesis. This article discusses the latest findings on such RNA toxicity pathways in ALS and potential novel therapeutic approaches.
Collapse
Affiliation(s)
- Christopher J Donnelly
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | | |
Collapse
|
310
|
Meneghello G, Verheyen A, Van Ingen M, Kuijlaars J, Tuefferd M, Van Den Wyngaert I, Nuydens R. Evaluation of established human iPSC-derived neurons to model neurodegenerative diseases. Neuroscience 2015; 301:204-12. [DOI: 10.1016/j.neuroscience.2015.05.071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 03/30/2015] [Accepted: 05/28/2015] [Indexed: 01/21/2023]
|
311
|
Yang DJ, Zhu L, Ren J, Ma RJ, Zhu H, Xu J. Dysfunction of autophagy as the pathological mechanism of motor neuron disease based on a patient-specific disease model. Neurosci Bull 2015. [PMID: 26219222 DOI: 10.1007/s12264-015-1541-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Autophagy is the main catabolic pathway in cells for the degradation of impaired proteins and organelles. Accumulating evidence supports the hypothesis that dysfunction of autophagy, leading to an imbalance of proteostasis and the accumulation of toxic proteins in neurons, is a central player in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS). The clinical pathology of ALS is complex and many genes associated with autophagy and RNA processing are mutated in patients with the familial form. But a causal relationship between autophagic dysfunction and ALS has not been fully established. More importantly, studies on the pathological mechanism of ALS are mainly based on animal models that may not precisely recapitulate the disease itself in human beings. The development of human iPSC techniques allows us to address these issues directly in human cell models that may profoundly influence drug discovery for ALS.
Collapse
Affiliation(s)
- Dan-Jing Yang
- Advanced Institute of Translational Medicine, Tongji University, Shanghai, 200092, China
| | | | | | | | | | | |
Collapse
|
312
|
Wang X, Zhou S, Ding X, Ma M, Zhang J, Zhou Y, Wu E, Teng J. Activation of ER Stress and Autophagy Induced by TDP-43 A315T as Pathogenic Mechanism and the Corresponding Histological Changes in Skin as Potential Biomarker for ALS with the Mutation. Int J Biol Sci 2015; 11:1140-9. [PMID: 26327808 PMCID: PMC4551750 DOI: 10.7150/ijbs.12657] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 06/18/2015] [Indexed: 12/12/2022] Open
Abstract
TAR DNA binding protein 43 (TDP-43) A315T mutation (TDP-43A315T) has been found in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) as a disease causing mutation with enhanced protein aggregation, formation of protease-resistant fragments, and neurotoxicity. However, the molecular mechanisms for its pathogenic effects are largely unknown. In this study, we demonstrate that TDP-43A315T enhanced neuronal toxicity via activating endoplasmic reticulum (ER) stress-mediated apoptosis in SH-SY5Y cells. Moreover, autophagy was activated by overexpression of TDP-43A315T in a self-defensive manner to decrease neuronal toxicity. Inhibition of autophagy attenuates TDP-43A315T induced neuronal cell death. Furthermore, the expression levels of TDP-43, ER chaperone 78 kDa glucose-regulated protein (GRP-78), and autophagy marker microtubule-associated protein 1A/1B-light chain 3 (LC3) in the skin tissues from ALS patients with TDP-43A315T mutation were markedly higher than those from the healthy control. Thus, our findings provide new molecular evidence for TDP-43A315T neuropathology. In addition, the pathological change in the skin tissues of the patients with TDP-43A315T mutation can be used as a quick diagnostic biomarker.
Collapse
Affiliation(s)
- Xuejing Wang
- 1. Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China
| | - Shuang Zhou
- 2. Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, 58105, USA
| | - Xuebing Ding
- 1. Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China
| | - Mingming Ma
- 3. Department of Neurology, People's Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Jiewen Zhang
- 3. Department of Neurology, People's Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Yue Zhou
- 4. Department of Statistics, North Dakota State University, Fargo, ND, 58105, USA
| | - Erxi Wu
- 2. Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, 58105, USA
| | - Junfang Teng
- 1. Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China
| |
Collapse
|
313
|
Jang W, Kim HJ, Li H, Jo KD, Lee MK, Yang HO. The Neuroprotective Effect of Erythropoietin on Rotenone-Induced Neurotoxicity in SH-SY5Y Cells Through the Induction of Autophagy. Mol Neurobiol 2015; 53:3812-3821. [PMID: 26156288 DOI: 10.1007/s12035-015-9316-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 06/23/2015] [Indexed: 12/25/2022]
Abstract
Currently, the autophagy pathway is thought to be important for the pathogenesis of Parkinson's disease (PD), and the modulation of autophagy may be a novel strategy for the treatment of this disease. Erythropoietin (EPO) has been reported to have neuroprotective effects through anti-oxidative, anti-apoptotic, and anti-inflammatory mechanisms, and it has also been shown to modulate autophagy signaling in an oxygen toxicity model. Therefore, we investigated the effects of EPO on autophagy markers and evaluated its neuroprotective effect on rotenone-induced neurotoxicity. We adapted the rotenone-induced neurotoxicity model to SH-SY5Y cells as an in vitro model of PD. We measured cell viability using MTT and annexin V/propidium iodide assays and measured intracellular levels of reactive oxygen species. Immunofluorescence analysis was performed to measure the expression of LC3 and α-synuclein. Intracellular signaling proteins associated with autophagy were examined by immunoblot analysis. EPO mono-treatment increased the levels of mammalian target of rapamycin (mTOR)-independent/upstream autophagy markers, including Beclin-1, AMPK, and ULK-1. Rotenone treatment of SH-SY5Y cells reduced their viability, increased reactive oxygen species levels, and induced apoptosis and α-synuclein expression, and simultaneous exposure to EPO significantly reduced these effects. Rotenone enhanced mTOR expression and suppressed Beclin-1 expression, indicating suppression of the autophagy system. However, combined treatment with EPO restored Beclin-1 expression and decreased mTOR expression. EPO protects against rotenone-induced neurotoxicity in SH-SY5Y cells by enhancing autophagy-related signaling pathways. The experimental evidence for the EPO-induced neuroprotection against rotenone-induced dopaminergic neurotoxicity may significantly impact the development of future PD treatment strategies.
Collapse
Affiliation(s)
- Wooyoung Jang
- Department of Neurology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Bangdong-ri, Sacheon-myeon, Gangneung, Gangwon-do, 210-711, Republic of Korea. .,Biomedical Research Center, Gangneung Asan Hospital, Bangdong-ri, Sacheon-myeon, Gangneung, 210-711, Gangwon-do, Republic of Korea.
| | - Hee Ju Kim
- Natural Products Research Center, Korea Institute of Science and Technology, 679 Saimdang-ro, Gangneung, 210-340, Republic of Korea.,Biomedical Research Center, Gangneung Asan Hospital, Bangdong-ri, Sacheon-myeon, Gangneung, 210-711, Gangwon-do, Republic of Korea
| | - Huan Li
- Natural Products Research Center, Korea Institute of Science and Technology, 679 Saimdang-ro, Gangneung, 210-340, Republic of Korea
| | - Kwang Deog Jo
- Department of Neurology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Bangdong-ri, Sacheon-myeon, Gangneung, Gangwon-do, 210-711, Republic of Korea
| | - Moon Kyu Lee
- Department of Neurology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Bangdong-ri, Sacheon-myeon, Gangneung, Gangwon-do, 210-711, Republic of Korea
| | - Hyun Ok Yang
- Natural Products Research Center, Korea Institute of Science and Technology, 679 Saimdang-ro, Gangneung, 210-340, Republic of Korea.
| |
Collapse
|
314
|
Chou CC, Alexeeva OM, Yamada S, Pribadi A, Zhang Y, Mo B, Williams KR, Zarnescu DC, Rossoll W. PABPN1 suppresses TDP-43 toxicity in ALS disease models. Hum Mol Genet 2015; 24:5154-73. [PMID: 26130692 DOI: 10.1093/hmg/ddv238] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 06/22/2015] [Indexed: 12/13/2022] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) is a major disease protein in amyotrophic lateral sclerosis (ALS) and related neurodegenerative diseases. Both the cytoplasmic accumulation of toxic ubiquitinated and hyperphosphorylated TDP-43 fragments and the loss of normal TDP-43 from the nucleus may contribute to the disease progression by impairing normal RNA and protein homeostasis. Therefore, both the removal of pathological protein and the rescue of TDP-43 mislocalization may be critical for halting or reversing TDP-43 proteinopathies. Here, we report poly(A)-binding protein nuclear 1 (PABPN1) as a novel TDP-43 interaction partner that acts as a potent suppressor of TDP-43 toxicity. Overexpression of full-length PABPN1 but not a truncated version lacking the nuclear localization signal protects from pathogenic TDP-43-mediated toxicity, promotes the degradation of pathological TDP-43 and restores normal solubility and nuclear localization of endogenous TDP-43. Reduced levels of PABPN1 enhances the phenotypes in several cell culture and Drosophila models of ALS and results in the cytoplasmic mislocalization of TDP-43. Moreover, PABPN1 rescues the dysregulated stress granule (SG) dynamics and facilitates the removal of persistent SGs in TDP-43-mediated disease conditions. These findings demonstrate a role for PABPN1 in rescuing several cytopathological features of TDP-43 proteinopathy by increasing the turnover of pathologic proteins.
Collapse
Affiliation(s)
- Ching-Chieh Chou
- Department of Cell Biology, Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | | - Shizuka Yamada
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA and
| | - Amy Pribadi
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA and
| | - Yi Zhang
- Department of Cell Biology, Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Bi Mo
- Department of Cell Biology
| | | | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA and
| | - Wilfried Rossoll
- Department of Cell Biology, Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, GA 30322, USA,
| |
Collapse
|
315
|
Crisp MJ, Mawuenyega KG, Patterson BW, Reddy NC, Chott R, Self WK, Weihl CC, Jockel-Balsarotti J, Varadhachary AS, Bucelli RC, Yarasheski KE, Bateman RJ, Miller TM. In vivo kinetic approach reveals slow SOD1 turnover in the CNS. J Clin Invest 2015; 125:2772-80. [PMID: 26075819 DOI: 10.1172/jci80705] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 05/07/2015] [Indexed: 12/27/2022] Open
Abstract
Therapeutic strategies that target disease-associated transcripts are being developed for a variety of neurodegenerative syndromes. Protein levels change as a function of their half-life, a property that critically influences the timing and application of therapeutics. In addition, both protein kinetics and concentration may play important roles in neurodegeneration; therefore, it is essential to understand in vivo protein kinetics, including half-life. Here, we applied a stable isotope-labeling technique in combination with mass spectrometric detection and determined the in vivo kinetics of superoxide dismutase 1 (SOD1), mutation of which causes amyotrophic lateral sclerosis. Application of this method to human SOD1-expressing rats demonstrated that SOD1 is a long-lived protein, with a similar half-life in both the cerebral spinal fluid (CSF) and the CNS. Additionally, in these animals, the half-life of SOD1 was longest in the CNS when compared with other tissues. Evaluation of this method in human subjects demonstrated successful incorporation of the isotope label in the CSF and confirmed that SOD1 is a long-lived protein in the CSF of healthy individuals. Together, the results of this study provide important insight into SOD1 kinetics and support application of this technique to the design and implementation of clinical trials that target long-lived CNS proteins.
Collapse
|
316
|
Hippocampal endosomal, lysosomal, and autophagic dysregulation in mild cognitive impairment: correlation with aβ and tau pathology. J Neuropathol Exp Neurol 2015; 74:345-58. [PMID: 25756588 DOI: 10.1097/nen.0000000000000179] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Endosomal-lysosomal and autophagic dysregulation occurs in the hippocampus in prodromal Alzheimer disease (AD), but its relationship with β-amyloid (Aβ) and tau pathology remains unclear. To investigate this issue, we performed immunoblot analysis of hippocampal homogenates from cases with an antemortem clinical diagnosis of no cognitive impairment, mild cognitive impairment (MCI), and AD. Western blot analysis revealed significant increases in the acid hydrolase cathepsin D and early endosome marker rabaptin5 in the MCI group compared with AD, whereas levels of phosphorylated mammalian target of rapamycin proteins (pmTOR), total mammalian target of rapamycin (mTOR), p62, traf6, and LilrB2 were comparable across clinical groups. Hippocampal Aβ1-40 and Aβ1-42 concentrations and AT8-immunopositive neurofibrillary tangle density were not significantly different across the clinical groups. Greater cathepsin D expression was associated with global cognitive score and episodic memory score but not with mini mental state examination or advanced neuropathology criteria. These results indicate that alterations in hippocampal endosomal-lysosomal proteins in MCI are independent of tau or Aβ pathology.
Collapse
|
317
|
Amelioration of toxicity in neuronal models of amyotrophic lateral sclerosis by hUPF1. Proc Natl Acad Sci U S A 2015; 112:7821-6. [PMID: 26056265 DOI: 10.1073/pnas.1509744112] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Over 30% of patients with amyotrophic lateral sclerosis (ALS) exhibit cognitive deficits indicative of frontotemporal dementia (FTD), suggesting a common pathogenesis for both diseases. Consistent with this hypothesis, neuronal and glial inclusions rich in TDP43, an essential RNA-binding protein, are found in the majority of those with ALS and FTD, and mutations in TDP43 and a related RNA-binding protein, FUS, cause familial ALS and FTD. TDP43 and FUS affect the splicing of thousands of transcripts, in some cases triggering nonsense-mediated mRNA decay (NMD), a highly conserved RNA degradation pathway. Here, we take advantage of a faithful primary neuronal model of ALS and FTD to investigate and characterize the role of human up-frameshift protein 1 (hUPF1), an RNA helicase and master regulator of NMD, in these disorders. We show that hUPF1 significantly protects mammalian neurons from both TDP43- and FUS-related toxicity. Expression of hUPF2, another essential component of NMD, also improves survival, whereas inhibiting NMD prevents rescue by hUPF1, suggesting that hUPF1 acts through NMD to enhance survival. These studies emphasize the importance of RNA metabolism in ALS and FTD, and identify a uniquely effective therapeutic strategy for these disorders.
Collapse
|
318
|
Wang X, Ma M, Teng J, Che X, Zhang W, Feng S, Zhou S, Zhang Y, Wu E, Ding X. Valproate Attenuates 25-kDa C-Terminal Fragment of TDP-43-Induced Neuronal Toxicity via Suppressing Endoplasmic Reticulum Stress and Activating Autophagy. Int J Biol Sci 2015; 11:752-61. [PMID: 26078717 PMCID: PMC4466456 DOI: 10.7150/ijbs.11880] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 04/17/2015] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disease. To date, there is no any effective pharmacological treatment for improving patients' symptoms and quality of life. Rapidly emerging evidence suggests that C-terminal fragments (CTFs) of TAR DNA-binding protein of 43 kDa (TDP-43), including TDP-35 and TDP-25, may play an important role in ALS pathogenesis. Valproate (VPA), a widely used antiepileptic drug, has neuroprotective effects on neurodegenerative disorders. As for ALS, preclinical studies also provide encouraging evidence for multiple beneficial effects in ALS mouse models. However, the potential molecular mechanisms have not been explored. Here, we show protective effects of VPA against TDP-43 CTFs-mediated neuronal toxicity and its underlying mechanisms in vitro. Remarkably, TDP-43 CTFs induced neuronal damage via endoplastic reticulum (ER) stress-mediated apoptosis. Furthermore, autophagic self-defense system was activated to reduce TDP-43 CTFs-induced neuronal death. Finally, VPA attenuated TDP-25-induced neuronal toxicity via suppressing ER stress-mediated apoptosis and enhancing autophagy. Taken together, these results demonstrate that VPA exerts neuroprotective effects against TDP-43 CTFs-induced neuronal damage. Thus, we provide new molecular evidence for VPA treatment in patients with ALS and other TDP-43 proteinopathies.
Collapse
Affiliation(s)
- Xuejing Wang
- 1. Department of neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Mingming Ma
- 2. Department of neurology, People's Hospital of Zhengzhou University, Zhengzhou, Henan 450003, China
| | - Junfang Teng
- 1. Department of neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Xiangqian Che
- 4. Department of Neurology, Ruijin Hospital, Shanghai Jiaotong University, Shanghai 200025, China
| | - Wenwen Zhang
- 1. Department of neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Shuman Feng
- 2. Department of neurology, People's Hospital of Zhengzhou University, Zhengzhou, Henan 450003, China
| | - Shuang Zhou
- 3. Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, 58105, USA
| | - Ying Zhang
- 3. Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, 58105, USA
| | - Erxi Wu
- 3. Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, 58105, USA
| | - Xuebing Ding
- 1. Department of neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| |
Collapse
|
319
|
Khurana V, Tardiff DF, Chung CY, Lindquist S. Toward stem cell-based phenotypic screens for neurodegenerative diseases. Nat Rev Neurol 2015; 11:339-50. [PMID: 25986505 DOI: 10.1038/nrneurol.2015.79] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In the absence of a single preventive or disease-modifying strategy, neurodegenerative diseases are becoming increasingly prevalent in our ageing population. The mechanisms underlying neurodegeneration are poorly understood, making the target-based drug screening strategies that are employed by the pharmaceutical industry fraught with difficulty. However, phenotypic screening in neurons and glia derived from patients is now conceivable through unprecedented developments in reprogramming, transdifferentiation, and genome editing. We outline progress in this nascent field, but also consider the formidable hurdles to identifying robust, disease-relevant and screenable cellular phenotypes in patient-derived cells. We illustrate how analysis in the simple baker's yeast cell Saccharaomyces cerevisiae is driving discovery in patient-derived neurons, and how approaches in this model organism can establish a paradigm to guide the development of stem cell-based phenotypic screens.
Collapse
Affiliation(s)
- Vikram Khurana
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, WACC-835, 15 Parkman Street, Boston, MA 02114, USA
| | - Daniel F Tardiff
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Chee Yeun Chung
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Susan Lindquist
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| |
Collapse
|
320
|
Defining the genetic connection linking amyotrophic lateral sclerosis (ALS) with frontotemporal dementia (FTD). Trends Genet 2015; 31:263-73. [DOI: 10.1016/j.tig.2015.03.005] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 03/10/2015] [Accepted: 03/10/2015] [Indexed: 12/11/2022]
|
321
|
Nah J, Yuan J, Jung YK. Autophagy in neurodegenerative diseases: from mechanism to therapeutic approach. Mol Cells 2015; 38:381-9. [PMID: 25896254 PMCID: PMC4443278 DOI: 10.14348/molcells.2015.0034] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 02/09/2015] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a lysosome-dependent intracellular degradation process that allows recycling of cytoplasmic constituents into bioenergetic and biosynthetic materials for maintenance of homeostasis. Since the function of autophagy is particularly important in various stress conditions, perturbation of autophagy can lead to cellular dysfunction and diseases. Accumulation of abnormal protein aggregates, a common cause of neurodegenerative diseases, can be reduced through autophagic degradation. Recent studies have revealed defects in autophagy in most cases of neurodegenerative disorders. Moreover, deregulated excessive autophagy can also cause neurodegeneration. Thus, healthy activation of autophagy is essential for therapeutic approaches in neurodegenerative diseases and many autophagy-regulating compounds are under development for therapeutic purposes. This review describes the overall role of autophagy in neurodegeneration, focusing on various therapeutic strategies for modulating specific stages of autophagy and on the current status of drug development.
Collapse
Affiliation(s)
- Jihoon Nah
- Global Research Laboratory, School of Biological Science, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-747,
Korea
| | - Junying Yuan
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115-5730,
USA
| | - Yong-Keun Jung
- Global Research Laboratory, School of Biological Science, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-747,
Korea
| |
Collapse
|
322
|
Ichida JK, Kiskinis E. Probing disorders of the nervous system using reprogramming approaches. EMBO J 2015; 34:1456-77. [PMID: 25925386 PMCID: PMC4474524 DOI: 10.15252/embj.201591267] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 04/14/2015] [Indexed: 11/09/2022] Open
Abstract
The groundbreaking technologies of induced pluripotency and lineage conversion have generated a genuine opportunity to address fundamental aspects of the diseases that affect the nervous system. These approaches have granted us unrestricted access to the brain and spinal cord of patients and have allowed for the study of disease in the context of human cells, expressing physiological levels of proteins and under each patient's unique genetic constellation. Along with this unprecedented opportunity have come significant challenges, particularly in relation to patient variability, experimental design and data interpretation. Nevertheless, significant progress has been achieved over the past few years both in our ability to create the various neural subtypes that comprise the nervous system and in our efforts to develop cellular models of disease that recapitulate clinical findings identified in patients. In this Review, we present tables listing the various human neural cell types that can be generated and the neurological disease modeling studies that have been reported, describe the current state of the field, highlight important breakthroughs and discuss the next steps and future challenges.
Collapse
Affiliation(s)
- Justin K Ichida
- Department of Stem Cells and Regenerative Medicine, Eli and Edythe Broad, CIRM Center for Regenerative Medicine and Stem Cell Research at USC, University of Southern California, Los Angeles, CA, USA
| | - Evangelos Kiskinis
- The Ken and Ruth Davee Department of Neurology & Clinical Neurological Sciences and Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| |
Collapse
|
323
|
Finkbeiner S, Frumkin M, Kassner PD. Cell-based screening: extracting meaning from complex data. Neuron 2015; 86:160-74. [PMID: 25856492 PMCID: PMC4457442 DOI: 10.1016/j.neuron.2015.02.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 09/23/2014] [Accepted: 01/22/2015] [Indexed: 01/23/2023]
Abstract
Unbiased discovery approaches have the potential to uncover neurobiological insights into CNS disease and lead to the development of therapies. Here, we review lessons learned from imaging-based screening approaches and recent advances in these areas, including powerful new computational tools to synthesize complex data into more useful knowledge that can reliably guide future research and development.
Collapse
Affiliation(s)
- Steven Finkbeiner
- Director of the Taube/Koret Center for Neurodegenerative Disease and the Hellman Family Foundation Program in Alzheimer's Disease Research, Gladstone Institute of Neurological Disease, San Francisco, CA 94158, USA; Departments of Neurology and Physiology, University of California, San Francisco, San Francisco, CA 94143, USA.
| | - Michael Frumkin
- Director of Engineering, Research, Google, Inc., 1600 Amphitheatre Parkway, Mountain View, CA 94043, USA
| | - Paul D Kassner
- Director of Research, Amgen, Inc., 1120 Veterans Boulevard South, San Francisco, CA 94080, USA
| |
Collapse
|
324
|
Scotter EL, Chen HJ, Shaw CE. TDP-43 Proteinopathy and ALS: Insights into Disease Mechanisms and Therapeutic Targets. Neurotherapeutics 2015; 12:352-63. [PMID: 25652699 PMCID: PMC4404432 DOI: 10.1007/s13311-015-0338-x] [Citation(s) in RCA: 199] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Therapeutic options for patients with amyotrophic lateral sclerosis (ALS) are currently limited. However, recent studies show that almost all cases of ALS, as well as tau-negative frontotemporal dementia (FTD), share a common neuropathology characterized by the deposition of TAR-DNA binding protein (TDP)-43-positive protein inclusions, offering an attractive target for the design and testing of novel therapeutics. Here we demonstrate how diverse environmental stressors linked to stress granule formation, as well as mutations in genes encoding RNA processing proteins and protein degradation adaptors, initiate ALS pathogenesis via TDP-43. We review the progressive development of TDP-43 proteinopathy from cytoplasmic mislocalization and misfolding through to macroaggregation and the addition of phosphate and ubiquitin moieties. Drawing from cellular and animal studies, we explore the feasibility of therapeutics that act at each point in pathogenesis, from mitigating genetic risk using antisense oligonucleotides to modulating TDP-43 proteinopathy itself using small molecule activators of autophagy, the ubiquitin-proteasome system, or the chaperone network. We present the case that preventing the misfolding of TDP-43 and/or enhancing its clearance represents the most important target for effectively treating ALS and frontotemporal dementia.
Collapse
Affiliation(s)
- Emma L. Scotter
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, de Crespigny Park, London, SE5 8AF UK
- Department of Pharmacology, University of Auckland, Auckland, New Zealand
- Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Han-Jou Chen
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, de Crespigny Park, London, SE5 8AF UK
| | - Christopher E. Shaw
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, de Crespigny Park, London, SE5 8AF UK
| |
Collapse
|
325
|
Abstract
The degeneration of motor neurons in amyotrophic lateral sclerosis (ALS) inevitably causes paralysis and death within a matter of years. Mounting genetic and functional evidence suggest that abnormalities in RNA processing and metabolism underlie motor neuron loss in sporadic and familial ALS. Abnormal localization and aggregation of essential RNA-binding proteins are fundamental pathological features of sporadic ALS, and mutations in genes encoding RNA processing enzymes cause familial disease. Also, expansion mutations occurring in the noncoding region of C9orf72-the most common cause of inherited ALS-result in nuclear RNA foci, underscoring the link between abnormal RNA metabolism and neurodegeneration in ALS. This review summarizes the current understanding of RNA dysfunction in ALS, and builds upon this knowledge base to identify converging mechanisms of neurodegeneration in ALS. Potential targets for therapy development are highlighted, with particular emphasis on early and conserved pathways that lead to motor neuron loss in ALS.
Collapse
Affiliation(s)
- Sami J Barmada
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, 5015 Biomedical Sciences Research Building, SSPC 2200, Ann Arbor, MI, 48109, USA,
| |
Collapse
|
326
|
Abstract
Loss of protein homeostasis (proteostasis) is a common feature of aging and disease that is characterized by the appearance of nonnative protein aggregates in various tissues. Protein aggregation is routinely suppressed by the proteostasis network (PN), a collection of macromolecular machines that operate in diverse ways to maintain proteome integrity across subcellular compartments and between tissues to ensure a healthy life span. Here, we review the composition, function, and organizational properties of the PN in the context of individual cells and entire organisms and discuss the mechanisms by which disruption of the PN, and related stress response pathways, contributes to the initiation and progression of disease. We explore emerging evidence that disease susceptibility arises from early changes in the composition and activity of the PN and propose that a more complete understanding of the temporal and spatial properties of the PN will enhance our ability to develop effective treatments for protein conformational diseases.
Collapse
Affiliation(s)
- Johnathan Labbadia
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, Illinois 60208;
| | | |
Collapse
|
327
|
Uversky VN. Intrinsically disordered proteins and their (disordered) proteomes in neurodegenerative disorders. Front Aging Neurosci 2015; 7:18. [PMID: 25784874 PMCID: PMC4345837 DOI: 10.3389/fnagi.2015.00018] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 02/13/2015] [Indexed: 12/14/2022] Open
Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida Tampa, FL, USA ; Biology Department, Faculty of Science, King Abdulaziz University Jeddah, Saudi Arabia ; Institute for Biological Instrumentation, Russian Academy of Sciences Pushchino, Russia ; Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences St. Petersburg, Russia
| |
Collapse
|
328
|
Lystad AH, Simonsen A. Assays to monitor aggrephagy. Methods 2015; 75:112-9. [DOI: 10.1016/j.ymeth.2014.12.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 12/12/2014] [Accepted: 12/22/2014] [Indexed: 12/15/2022] Open
|
329
|
Autophagy receptor defects and ALS-FTLD. Mol Cell Neurosci 2015; 66:43-52. [PMID: 25683489 DOI: 10.1016/j.mcn.2015.01.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/16/2015] [Accepted: 01/27/2015] [Indexed: 12/11/2022] Open
Abstract
Various pathophysiological mechanisms have been implicated in the ALS-FTLD clinicopathological spectrum of neurodegenerative disorders. Here we focus on the role of autophagy, an intracellular catabolic pathway, in these conditions. Growing evidence suggests that the autophagic process can be disturbed in ALS-FTLD, including by genetic mutations affecting autophagy receptor proteins (ubiquilin-2, optineurin, SQSTM1/p62) and regulators (VCP). Such mutations may impair clearance of autophagy substrates with pathological consequences. Recent studies have also uncovered a direct connection between autophagy and RNA processing, supporting an integrated model connecting several ALS-FTLD associated gene products. This article is part of a Special Issue entitled 'Neuronal Protein'.
Collapse
|
330
|
Maniecka Z, Polymenidou M. From nucleation to widespread propagation: A prion-like concept for ALS. Virus Res 2015; 207:94-105. [PMID: 25656065 DOI: 10.1016/j.virusres.2014.12.032] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/12/2014] [Accepted: 12/29/2014] [Indexed: 12/12/2022]
Abstract
Propagation of pathological protein assemblies via a prion-like mechanism has been suggested to drive neurodegenerative diseases, such as Parkinson's and Alzheimer's. Recently, amyotrophic lateral sclerosis (ALS)-linked proteins, such as SOD1, TDP-43 and FUS were shown to follow self-perpetuating seeded aggregation, thereby adding ALS to the group of prion-like disorders. The cell-to-cell spread of these pathological protein assemblies and their pathogenic mechanism is poorly understood. However, as ALS is a non-cell autonomous disease and pathology in glial cells was shown to contribute to motor neuron damage, spreading mechanisms are likely to underlie disease progression via the interplay between affected neurons and their neighboring glial cells.
Collapse
Affiliation(s)
- Zuzanna Maniecka
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Magdalini Polymenidou
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| |
Collapse
|
331
|
Abstract
Most neurodegenerative diseases that afflict humans are associated with the intracytoplasmic deposition of aggregate-prone proteins in neurons. Autophagy is a powerful process for removing such proteins. In this Review, we consider how certain neurodegenerative diseases may be associated with impaired autophagy and how this may affect pathology. We also discuss how autophagy induction may be a plausible therapeutic strategy for some conditions and review studies in various models that support this hypothesis. Finally, we briefly describe some of the signaling pathways that may be amenable to therapeutic targeting for these goals.
Collapse
|
332
|
Buratti E. Functional Significance of TDP-43 Mutations in Disease. ADVANCES IN GENETICS 2015; 91:1-53. [DOI: 10.1016/bs.adgen.2015.07.001] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
333
|
Dual Role of Autophagy in Neurodegenerative Diseases: The Case of Amyotrophic Lateral Sclerosis. CURRENT TOPICS IN NEUROTOXICITY 2015. [DOI: 10.1007/978-3-319-13939-5_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
334
|
Jaronen M, Goldsteins G, Koistinaho J. ER stress and unfolded protein response in amyotrophic lateral sclerosis-a controversial role of protein disulphide isomerase. Front Cell Neurosci 2014; 8:402. [PMID: 25520620 PMCID: PMC4251436 DOI: 10.3389/fncel.2014.00402] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 11/07/2014] [Indexed: 01/20/2023] Open
Abstract
Accumulation of proteins in aberrant conformation occurs in many neurodegenerative diseases. Furthermore, dysfunctions in protein handling in endoplasmic reticulum (ER) and the following ER stress have been implicated in a vast number of diseases, such as amyotrophic lateral sclerosis (ALS). During excessive ER stress unfolded protein response (UPR) is activated to return ER to its normal physiological balance. The exact mechanisms of protein misfolding, accumulation and the following ER stress, which could lead to neurodegeneration, and the question whether UPR is a beneficial compensatory mechanism slowing down the neurodegenerative processes, are of interest. Protein disulphide isomerase (PDI) is a disulphide bond-modulating ER chaperone, which can also facilitate the ER-associated degradation (ERAD) of misfolded proteins. In this review we discuss the recent findings of ER stress, UPR and especially the role of PDI in ALS.
Collapse
Affiliation(s)
- Merja Jaronen
- Department of Neurobiology, A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland Kuopio, Finland ; Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Gundars Goldsteins
- Department of Neurobiology, A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland Kuopio, Finland
| | - Jari Koistinaho
- Department of Neurobiology, A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland Kuopio, Finland
| |
Collapse
|
335
|
Lattante S, de Calbiac H, Le Ber I, Brice A, Ciura S, Kabashi E. Sqstm1 knock-down causes a locomotor phenotype ameliorated by rapamycin in a zebrafish model of ALS/FTLD. Hum Mol Genet 2014; 24:1682-90. [PMID: 25410659 DOI: 10.1093/hmg/ddu580] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Mutations in SQSTM1, encoding for the protein SQSTM1/p62, have been recently reported in 1-3.5% of patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration (ALS/FTLD). Inclusions positive for SQSTM1/p62 have been detected in patients with neurodegenerative disorders, including ALS/FTLD. In order to investigate the pathogenic mechanisms induced by SQSTM1 mutations in ALS/FTLD, we developed a zebrafish model. Knock-down of the sqstm1 zebrafish ortholog, as well as impairment of its splicing, led to a specific phenotype, consisting of behavioral and axonal anomalies. Here, we report swimming deficits associated with shorter motor neuronal axons that could be rescued by the overexpression of wild-type human SQSTM1. Interestingly, no rescue of the loss-of-function phenotype was observed when overexpressing human SQSTM1 constructs carrying ALS/FTLD-related mutations. Consistent with its role in autophagy regulation, we found increased mTOR levels upon knock-down of sqstm1. Furthermore, treatment of zebrafish embryos with rapamycin, a known inhibitor of the mTOR pathway, yielded an amelioration of the locomotor phenotype in the sqstm1 knock-down model. Our results suggest that loss-of-function of SQSTM1 causes phenotypic features characterized by locomotor deficits and motor neuron axonal defects that are associated with a misregulation of autophagic processes.
Collapse
Affiliation(s)
- Serena Lattante
- Sorbonne Université, UPMC Univ Paris 06, UM 75, ICM; Inserm, U 1127, ICM; Cnrs, UMR 7225, ICM; ICM, Paris, F-75013 Paris, France
| | - Hortense de Calbiac
- Sorbonne Université, UPMC Univ Paris 06, UM 75, ICM; Inserm, U 1127, ICM; Cnrs, UMR 7225, ICM; ICM, Paris, F-75013 Paris, France
| | - Isabelle Le Ber
- Sorbonne Université, UPMC Univ Paris 06, UM 75, ICM; Inserm, U 1127, ICM; Cnrs, UMR 7225, ICM; ICM, Paris, F-75013 Paris, France, AP-HP, Hôpital de la Salpêtrière, Centre de Référence Démences Rares, F-75013, Paris, France
| | - Alexis Brice
- Sorbonne Université, UPMC Univ Paris 06, UM 75, ICM; Inserm, U 1127, ICM; Cnrs, UMR 7225, ICM; ICM, Paris, F-75013 Paris, France, AP-HP, Hôpital de la Salpêtrière, Département de Génétique et Cytogénétique, F-75013, Paris, France
| | - Sorana Ciura
- Sorbonne Université, UPMC Univ Paris 06, UM 75, ICM; Inserm, U 1127, ICM; Cnrs, UMR 7225, ICM; ICM, Paris, F-75013 Paris, France,
| | - Edor Kabashi
- Sorbonne Université, UPMC Univ Paris 06, UM 75, ICM; Inserm, U 1127, ICM; Cnrs, UMR 7225, ICM; ICM, Paris, F-75013 Paris, France,
| |
Collapse
|
336
|
Toops KA, Tan LX, Jiang Z, Radu RA, Lakkaraju A. Cholesterol-mediated activation of acid sphingomyelinase disrupts autophagy in the retinal pigment epithelium. Mol Biol Cell 2014; 26:1-14. [PMID: 25378587 PMCID: PMC4279221 DOI: 10.1091/mbc.e14-05-1028] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
How autophagy is regulated in the postmitotic retinal pigment epithelium (RPE) is unclear. Visual cycle metabolites and cholesterol that accumulate in the RPE inhibit autophagic flux by activating acid sphingomyelinase (ASMase). Increased ceramide promotes tubulin acetylation, which prevents autophagosome traffic. ASMase inhibition restores RPE autophagy. Autophagy is an essential mechanism for clearing damaged organelles and proteins within the cell. As with neurodegenerative diseases, dysfunctional autophagy could contribute to blinding diseases such as macular degeneration. However, precisely how inefficient autophagy promotes retinal damage is unclear. In this study, we investigate innate mechanisms that modulate autophagy in the retinal pigment epithelium (RPE), a key site of insult in macular degeneration. High-speed live imaging of polarized adult primary RPE cells and data from a mouse model of early-onset macular degeneration identify a mechanism by which lipofuscin bisretinoids, visual cycle metabolites that progressively accumulate in the RPE, disrupt autophagy. We demonstrate that bisretinoids trap cholesterol and bis(monoacylglycero)phosphate, an acid sphingomyelinase (ASMase) cofactor, within the RPE. ASMase activation increases cellular ceramide, which promotes tubulin acetylation on stabilized microtubules. Live-imaging data show that autophagosome traffic and autophagic flux are inhibited in RPE with acetylated microtubules. Drugs that remove excess cholesterol or inhibit ASMase reverse this cascade of events and restore autophagosome motility and autophagic flux in the RPE. Because accumulation of lipofuscin bisretinoids and abnormal cholesterol homeostasis are implicated in macular degeneration, our studies suggest that ASMase could be a potential therapeutic target to ensure the efficient autophagy that maintains RPE health.
Collapse
Affiliation(s)
- Kimberly A Toops
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, McPherson Eye Research Institute, and
| | - Li Xuan Tan
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53706
| | - Zhichun Jiang
- Jules Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA 90024
| | - Roxana A Radu
- Jules Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA 90024
| | - Aparna Lakkaraju
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, McPherson Eye Research Institute, and Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53706
| |
Collapse
|
337
|
First aid for a damaged proteome. Nat Chem Biol 2014; 10:869. [DOI: 10.1038/nchembio.1684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
338
|
Combating neurodegenerative disease with chemical probes and model systems. Nat Chem Biol 2014; 10:911-20. [PMID: 25325702 DOI: 10.1038/nchembio.1663] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/11/2014] [Indexed: 12/19/2022]
Abstract
The disheartening results of recent clinical trials for neurodegenerative disease (ND) therapeutics underscore the need for a more comprehensive understanding of the underlying disease biology before effective therapies can be devised. One hallmark of many NDs is a disruption in protein homeostasis. Therefore, investigating the role of protein homeostasis in these diseases is central to delineating their underlying pathobiology. Here, we review the seminal role that chemical biology has played in furthering the research on and treatment of dysfunctional protein homeostasis in NDs. We also discuss the vital and predictive role of model systems in identifying conserved homeostasis pathways and genes therein that are altered in neurodegeneration. Integrating approaches from chemical biology with the use of model systems yields a powerful toolkit with which to unravel the complexities of ND biology.
Collapse
|