1
|
Kurepa J, Bruce KA, Gerhardt GA, Smalle JA. A Plant Model of α-Synucleinopathy: Expression of α-Synuclein A53T Variant in Hairy Root Cultures Leads to Proteostatic Stress and Dysregulation of Iron Metabolism. APPLIED BIOSCIENCES 2024; 3:233-249. [PMID: 38835931 PMCID: PMC11149894 DOI: 10.3390/applbiosci3020016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Synucleinopathies, typified by Parkinson's disease (PD), entail the accumulation of α-synuclein (αSyn) aggregates in nerve cells. Various αSyn mutants, including the αSyn A53T variant linked to early-onset PD, increase the propensity for αSyn aggregate formation. In addition to disrupting protein homeostasis and inducing proteostatic stress, the aggregation of αSyn in PD is associated with an imbalance in iron metabolism, which increases the generation of reactive oxygen species and causes oxidative stress. This study explored the impact of αSyn A53T expression in transgenic hairy roots of four medicinal plants (Lobelia cardinalis, Artemisia annua, Salvia miltiorrhiza, and Polygonum multiflorum). In all tested plants, αSyn A53T expression triggered proteotoxic stress and perturbed iron homeostasis, mirroring the molecular profile observed in human and animal nerve cells. In addition to the common eukaryotic defense mechanisms against proteostatic and oxidative stresses, a plant stress response generally includes the biosynthesis of a diverse set of protective secondary metabolites. Therefore, the hairy root cultures expressing αSyn A53T offer a platform for identifying secondary metabolites that can ameliorate the effects of αSyn, thereby aiding in the development of possible PD treatments and/or treatments of synucleinopathies.
Collapse
Affiliation(s)
- Jasmina Kurepa
- Department of Plant and Soil Sciences, Martin-Gatton College of Agriculture Food and Environment, Kentucky Tobacco Research & Development Center, University of Kentucky, Lexington, KY 40546, USA
| | - Kristen A. Bruce
- Naprogenix, Inc., UK-AsTeCC, 145 Graham Avenue, Lexington, KY 40506, USA
| | - Greg A. Gerhardt
- Brain Restoration Center, University of Kentucky, Lexington, KY 40536, USA
- Department of Neurosurgery, University of Kentucky, Lexington, KY 40536, USA
- Department of Neuroscience, University of Kentucky, Lexington, KY 40536, USA
- Department of Neurology, University of Kentucky, Lexington, KY 40536, USA
| | - Jan A. Smalle
- Department of Plant and Soil Sciences, Martin-Gatton College of Agriculture Food and Environment, Kentucky Tobacco Research & Development Center, University of Kentucky, Lexington, KY 40546, USA
| |
Collapse
|
2
|
Moors TE, Milovanovic D. Defining a Lewy Body: Running Up the Hill of Shifting Definitions and Evolving Concepts. JOURNAL OF PARKINSON'S DISEASE 2024; 14:17-33. [PMID: 38189713 PMCID: PMC10836569 DOI: 10.3233/jpd-230183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/14/2023] [Indexed: 01/09/2024]
Abstract
Lewy bodies (LBs) are pathological hallmarks of Parkinson's disease and dementia with Lewy bodies, characterized by the accumulation of α-synuclein (αSyn) protein in the brain. While LBs were first described a century ago, their formation and morphogenesis mechanisms remain incompletely understood. Here, we present a historical overview of LB definitions and highlight the importance of semantic clarity and precise definitions when describing brain inclusions. Recent breakthroughs in imaging revealed shared features within LB subsets and the enrichment of membrane-bound organelles in these structures, challenging the conventional LB formation model. We discuss the involvement of emerging concepts of liquid-liquid phase separation, where biomolecules demix from a solution to form dense condensates, as a potential LB formation mechanism. Finally, we emphasize the need for the operational definitions of LBs based on morphological characteristics and detection protocols, particularly in studies investigating LB formation mechanisms. A better understanding of LB organization and ultrastructure can contribute to the development of targeted therapeutic strategies for synucleinopathies.
Collapse
Affiliation(s)
- Tim E. Moors
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Dragomir Milovanovic
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
- Einstein Center for Neuroscience, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Berlin, Germany
| |
Collapse
|
3
|
Borland H, Rasmussen I, Bjerregaard-Andersen K, Rasmussen M, Olsen A, Vilhardt F. α-synuclein build-up is alleviated via ESCRT-dependent endosomal degradation brought about by p38MAPK inhibition in cells expressing p25α. J Biol Chem 2022; 298:102531. [PMID: 36162505 PMCID: PMC9637583 DOI: 10.1016/j.jbc.2022.102531] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 08/24/2022] [Accepted: 09/04/2022] [Indexed: 11/24/2022] Open
Abstract
α-synucleinopathy is driven by an imbalance of synthesis and degradation of α-synuclein (αSyn), causing a build up of αSyn aggregates and post-translationally modified species, which not only interfere with normal cellular metabolism but also by their secretion propagates the disease. Therefore, a better understanding of αSyn degradation pathways is needed to address α-synucleinopathy. Here, we used the nerve growth factor–differentiated catecholaminergic PC12 neuronal cell line, which was conferred α-synucleinopathy by inducible expression of αSyn and tubulin polymerization-promoting protein p25α. p25α aggregates αSyn, and imposes a partial autophagosome–lysosome block to mimic aspects of lysosomal deficiency common in neurodegenerative disease. Under basal conditions, αSyn was degraded by multiple pathways but most prominently by macroautophagy and Nedd4/Ndfip1-mediated degradation. We found that expression of p25α induced strong p38MAPK activity. Remarkably, when opposed by inhibitor SB203580 or p38MAPK shRNA knockdown, endolysosomal localization and degradation of αSyn increased, and αSyn secretion and cytotoxicity decreased. This effect was specifically dependent on Hsc70 and the endosomal sorting complex required for transport machinery, but different from classical microautophagy, as the αSyn Hsc70 binding motif was unnecessary. Furthermore, in a primary neuronal (h)-αSyn seeding model, p38MAPK inhibition decreased pathological accumulation of phosphorylated serine-129-αSyn and cytotoxicity. In conclusion, p38MAPK inhibition shifts αSyn degradation from various forms of autophagy to an endosomal sorting complex required for transport–dependent uptake mechanism, resulting in increased αSyn turnover and cell viability in p25α-expressing cells. More generally, our results suggest that under conditions of autophagolysosomal malfunction, the uninterrupted endosomal pathway offers a possibility to achieve disease-associated protein degradation.
Collapse
Affiliation(s)
- Helena Borland
- Dept. of Cellular and Molecular Medicine, The Panum Institute, The Faculty of Health Sciences, University of Copenhagen, Copenhagen 2200N, Denmark; Dept. of Cell Biology, H. Lundbeck A/S, 2500 Valby, Denmark.
| | - Izabela Rasmussen
- Dept. of Cellular and Molecular Medicine, The Panum Institute, The Faculty of Health Sciences, University of Copenhagen, Copenhagen 2200N, Denmark.
| | | | - Michel Rasmussen
- Dept. of Cellular and Molecular Medicine, The Panum Institute, The Faculty of Health Sciences, University of Copenhagen, Copenhagen 2200N, Denmark.
| | - Anders Olsen
- Dept. of Chemistry and Bioscience, The Faculty of Engineering and Science, University of Aalborg, Fredrik Bajers Vej 7H, 9220 Aalborg, Denmark.
| | - Frederik Vilhardt
- Dept. of Cellular and Molecular Medicine, The Panum Institute, The Faculty of Health Sciences, University of Copenhagen, Copenhagen 2200N, Denmark.
| |
Collapse
|
4
|
Sahoo S, Padhy AA, Kumari V, Mishra P. Role of Ubiquitin-Proteasome and Autophagy-Lysosome Pathways in α-Synuclein Aggregate Clearance. Mol Neurobiol 2022; 59:5379-5407. [PMID: 35699874 DOI: 10.1007/s12035-022-02897-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/21/2022] [Indexed: 11/26/2022]
Abstract
Synuclein aggregation in neuronal cells is the primary underlying cause of synucleinopathies. Changes in gene expression patterns, structural modifications, and altered interactions with other cellular proteins often trigger aggregation of α-synuclein, which accumulates as oligomers or fibrils in Lewy bodies. Although fibrillar forms of α-synuclein are primarily considered pathological, recent studies have revealed that even the intermediate states of aggregates are neurotoxic, complicating the development of therapeutic interventions. Autophagy and ubiquitin-proteasome pathways play a significant role in maintaining the soluble levels of α-synuclein inside cells; however, the heterogeneous nature of the aggregates presents a significant bottleneck to its degradation by these cellular pathways. With studies focused on identifying the proteins that modulate synuclein aggregation and clearance, detailed mechanistic insights are emerging about the individual and synergistic effects of these degradation pathways in regulating soluble α-synuclein levels. In this article, we discuss the impact of α-synuclein aggregation on autophagy-lysosome and ubiquitin-proteasome pathways and the therapeutic strategies that target various aspects of synuclein aggregation or degradation via these pathways. Additionally, we also highlight the natural and synthetic compounds that have shown promise in alleviating the cellular damage caused due to synuclein aggregation.
Collapse
Affiliation(s)
- Subhashree Sahoo
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Amrita Arpita Padhy
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Varsha Kumari
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Parul Mishra
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India.
| |
Collapse
|
5
|
Kim HJ, Koh HC. Chaperon-mediated autophagy can regulate diquat-induced apoptosis by inhibiting α-synuclein accumulation cooperatively with macroautophagy. Food Chem Toxicol 2021; 158:112706. [PMID: 34848256 DOI: 10.1016/j.fct.2021.112706] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/03/2021] [Accepted: 11/24/2021] [Indexed: 11/17/2022]
Abstract
α-Synuclein, which is associated with Parkinson's disease, is cleared by the ubiquitin-proteasome system and autophagy lysosome system. Chaperon-mediated autophagy (CMA) and macroautophagy are major subtypes of autophagy and play a critical role in pesticide-induced α-synucleinopathy. In this study, we explored the role of CMA in diquat (DQ)-induced α-synucleinopathy and characterized the relationship between CMA and macroautophagy in the clearance of pathologic α-synuclein for the prevention of DQ neurotoxicity. DQ was cytotoxic to SH-SY5Y cells in a concentration-dependent manner, as shown by decreased cell viability and increased cytotoxicity. DQ treatment was also found to induce autophagy such as CMA and macroautophagy by monitoring the expression of Lamp2A and microtubule-associated protein 1A/1B light chain 3B (LC3-II) respectively. Following DQ treatment, SH-SY5Y cells were found to have induced phosphorylated and detergent-insoluble α-synuclein deposits, and MG132, a proteasome inhibitor, effectively potentiated both CMA and macroautophagy for preventing α-synuclein aggregation. Interestingly, CMA impairment by Lamp2A-knock down decreased the LC3II expression compared to in DQ-treated cells transfected with control siRNA. In Lamp2-knock down cells, pathologic α-synuclein was increased 12 h after DQ treatment, but there was no change observed at 24 h. In DQ-treated cells, macroautophagy by 3-methyladenine and bafilomycin inhibition increased Lamp2A expression, indicating an increase in CMA activity. In addition, CMA modulation affected apoptosis, and inhibiting lysosome activity by NH4Cl increased apoptosis in DQ-treated cells. An increase in autophagy was confirmed to compensate for the decrease in lysosome activity. Pretreatment with z-VAD-fmk, a pan-caspase inhibitor, significantly enhanced the macroautophagy response of DQ-exposed cells without alterations in Lamp2A expression. Our results suggest that CMA can regulate DQ-induced α-synucleinopathy cooperatively with macroautophagy, and crosstalk between macroautophagy and CMA plays an important role in DQ-induced cytotoxicity. Taken together, autophagy modulation may be a useful treatment strategy in pesticide-induced neurodegenerative disorders through preventing α-synucleinopathy.
Collapse
Affiliation(s)
- Hong Ju Kim
- Department of Pharmacology, College of Medicine, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea; Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea
| | - Hyun Chul Koh
- Department of Pharmacology, College of Medicine, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea; Hanyang Biomedical Research Institute, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea; Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea.
| |
Collapse
|
6
|
Bi M, Du X, Xiao X, Dai Y, Jiao Q, Chen X, Zhang L, Jiang H. Deficient immunoproteasome assembly drives gain of α-synuclein pathology in Parkinson's disease. Redox Biol 2021; 47:102167. [PMID: 34662812 PMCID: PMC8577461 DOI: 10.1016/j.redox.2021.102167] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 01/07/2023] Open
Abstract
Aberrant α-synuclein (α-Syn) accumulation resulting from proteasome dysfunction is considered as a prominent factor to initiate and aggravate the neurodegeneration in Parkinson's disease (PD). Although the involvement of 26S proteasome in proteostasis imbalance has been widely accepted, our knowledge about the regulation of immunoproteasome function and its potential role in α-Syn pathology remains limited. Immunoproteasome abundance and proteolytic activities depend on the finely tuned assembly process, especially β-ring formation mediated by the only well-known chaperone proteasome maturation protein (POMP). Here, we identified that α-Syn overexpression was associated with a reduction in immunoproteasome function, which in turn limited the degradation of polo-like kinase 2 (PLK2), exacerbated α-Syn Ser129 phosphorylation and aggregation, ultimately leading to the neurodegeneration. These effects could be dramatically attenuated by β5i overexpression. Mechanistically, α-Syn suppressed the transcriptional regulation of POMP by nuclear factor erythroid 2-related factor 2 (NRF2), thereby preventing the assembly of immunoproteasome β subunits. Dopaminergic neurons-specific overexpression of NRF2-POMP axis effectively rescued the aggregation of α-Syn and PD-like phenotypes. These findings characterized abnormal immunoproteasome assembly as a key contributor governing α-Syn accumulation and neurodegeneration, which might open up a new perspective for the implication of immunoproteasome in PD and provide approaches of manipulating immunoproteasome assembly for therapeutic purposes. α-Syn negatively regulated immunoproteasome by inhibiting POMP-mediated assembly. Immunoproteasome deficiency prevented PLK2 degradation to aggravate neurotoxicity. Enhanced immunoproteasome assembly via NRF2-POMP axis alleviated α-Syn pathology.
Collapse
Affiliation(s)
- Mingxia Bi
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Xixun Du
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Xue Xiao
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Yingying Dai
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Qian Jiao
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Xi Chen
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Lingqiang Zhang
- State Key Laboratory of Proteomics, National Center for Protein Sciences (Beijing), Beijing Institute of Lifeomics, Beijing, China
| | - Hong Jiang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China.
| |
Collapse
|
7
|
Mavroeidi P, Xilouri M. Neurons and Glia Interplay in α-Synucleinopathies. Int J Mol Sci 2021; 22:4994. [PMID: 34066733 PMCID: PMC8125822 DOI: 10.3390/ijms22094994] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/29/2021] [Accepted: 05/04/2021] [Indexed: 11/16/2022] Open
Abstract
Accumulation of the neuronal presynaptic protein alpha-synuclein within proteinaceous inclusions represents the key histophathological hallmark of a spectrum of neurodegenerative disorders, referred to by the umbrella term a-synucleinopathies. Even though alpha-synuclein is expressed predominantly in neurons, pathological aggregates of the protein are also found in the glial cells of the brain. In Parkinson's disease and dementia with Lewy bodies, alpha-synuclein accumulates mainly in neurons forming the Lewy bodies and Lewy neurites, whereas in multiple system atrophy, the protein aggregates mostly in the glial cytoplasmic inclusions within oligodendrocytes. In addition, astrogliosis and microgliosis are found in the synucleinopathy brains, whereas both astrocytes and microglia internalize alpha-synuclein and contribute to the spread of pathology. The mechanisms underlying the pathological accumulation of alpha-synuclein in glial cells that under physiological conditions express low to non-detectable levels of the protein are an area of intense research. Undoubtedly, the presence of aggregated alpha-synuclein can disrupt glial function in general and can contribute to neurodegeneration through numerous pathways. Herein, we summarize the current knowledge on the role of alpha-synuclein in both neurons and glia, highlighting the contribution of the neuron-glia connectome in the disease initiation and progression, which may represent potential therapeutic target for a-synucleinopathies.
Collapse
Affiliation(s)
| | - Maria Xilouri
- Center of Clinical Research, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, 11527 Athens, Greece;
| |
Collapse
|
8
|
Ke M, Chong CM, Zhu Q, Zhang K, Cai CZ, Lu JH, Qin D, Su H. Comprehensive Perspectives on Experimental Models for Parkinson's Disease. Aging Dis 2021; 12:223-246. [PMID: 33532138 PMCID: PMC7801282 DOI: 10.14336/ad.2020.0331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 03/31/2020] [Indexed: 11/19/2022] Open
Abstract
Parkinson’s disease (PD) ranks second among the most common neurodegenerative diseases, characterized by progressive and selective loss of dopaminergic neurons. Various cross-species preclinical models, including cellular models and animal models, have been established through the decades to study the etiology and mechanism of the disease from cell lines to nonhuman primates. These models are aimed at developing effective therapeutic strategies for the disease. None of the current models can replicate all major pathological and clinical phenotypes of PD. Selection of the model for PD largely relies on our interest of study. In this review, we systemically summarized experimental PD models, including cellular and animal models used in preclinical studies, to understand the pathogenesis of PD. This review is intended to provide current knowledge about the application of these different PD models, with focus on their strengths and limitations with respect to their contributions to the assessment of the molecular pathobiology of PD and identification of the therapeutic strategies for the disease.
Collapse
Affiliation(s)
- Minjing Ke
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Cheong-Meng Chong
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Qi Zhu
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Ke Zhang
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Cui-Zan Cai
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Jia-Hong Lu
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Dajiang Qin
- 2Guangzhou Regenerative Medicine and Health Guangdong Laboratory, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,3South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Huanxing Su
- 1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| |
Collapse
|
9
|
Reverse engineering Lewy bodies: how far have we come and how far can we go? Nat Rev Neurosci 2021; 22:111-131. [PMID: 33432241 DOI: 10.1038/s41583-020-00416-6] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2020] [Indexed: 12/19/2022]
Abstract
Lewy bodies (LBs) are α-synuclein (α-syn)-rich intracellular inclusions that are an important pathological hallmark of Parkinson disease and several other neurodegenerative diseases. Increasing evidence suggests that the aggregation of α-syn has a central role in LB formation and is one of the key processes that drive neurodegeneration and pathology progression in Parkinson disease. However, little is known about the mechanisms underlying the formation of LBs, their biochemical composition and ultrastructural properties, how they evolve and spread with disease progression, and their role in neurodegeneration. In this Review, we discuss current knowledge of α-syn pathology, including the biochemical, structural and morphological features of LBs observed in different brain regions. We also review the most used cellular and animal models of α-syn aggregation and pathology spreading in relation to the extent to which they reproduce key features of authentic LBs. Finally, we provide important insights into molecular and cellular determinants of LB formation and spreading, and highlight the critical need for more detailed and systematic characterization of α-syn pathology, at both the biochemical and structural levels. This would advance our understanding of Parkinson disease and other neurodegenerative diseases and allow the development of more-reliable disease models and novel effective therapeutic strategies.
Collapse
|
10
|
Li M, Hu J, Yuan X, Shen L, Zhu L, Luo Q. Hepcidin Decreases Rotenone-Induced α-Synuclein Accumulation via Autophagy in SH-SY5Y Cells. Front Mol Neurosci 2020; 13:560891. [PMID: 33177988 PMCID: PMC7596286 DOI: 10.3389/fnmol.2020.560891] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 09/11/2020] [Indexed: 12/11/2022] Open
Abstract
Parkinson’s disease (PD) is a neurodegenerative disorder, and the hallmarks of this disease include iron deposition and α-synuclein (α-syn) aggregation. Hepcidin could reduce iron in the central and peripheral nervous systems. Here, we hypothesized that hepcidin could further decrease α-syn accumulation via reducing iron. Therefore, rotenone or α-syn was introduced into human neuroblastoma SH-SY5Y cells to imitate the pathological progress of PD in vitro. This study investigated the clearance effects of hepcidin on α-syn induced by a relatively low concentration of rotenone exposure or α-syn overexpression to elucidate the potential clearance pathway involved in this process. We demonstrated that SH-SY5Y cell viability was impaired after rotenone treatment in a dose-dependent manner. α-syn expression and iron content increased under a low concentration rotenone (25 nM for 3 days) treatment in SH-SY5Y cells. Pre-treatment with hepcidin peptide suppressed the abovementioned effects of rotenone. However, hepcidin did not affect treatment with rotenone under high iron conditions. Hepcidin also played a role in reducing α-syn accumulation in rotenone and α-syn overexpression conditions. We identified that the probable clearance effect of hepcidin on α-syn was mediated by the autophagy pathway using pretreatment with autophagy inhibitors (3-MA and CQ) and detection of autophagy protein markers (LC3II/I and p62). In conclusion, hepcidin eliminated α-syn expression via the autophagy pathway in rotenone-treated and α-syn overexpression SH-SY5Y cells. This study highlights that hepcidin may offer a potential therapeutic perspective in α-syn accumulation diseases.
Collapse
Affiliation(s)
- Meiqi Li
- Department of Physiology and Hypoxic Biomedicine, Institute of Special Environmental Medicine and Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Jianan Hu
- Department of Physiology and Hypoxic Biomedicine, Institute of Special Environmental Medicine and Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Xiaoyu Yuan
- Department of Emergency, Affiliated Hospital of Nantong University, Nantong, China
| | - Lihua Shen
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong, China
| | - Li Zhu
- Department of Physiology and Hypoxic Biomedicine, Institute of Special Environmental Medicine and Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Qianqian Luo
- Department of Physiology and Hypoxic Biomedicine, Institute of Special Environmental Medicine and Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| |
Collapse
|
11
|
Proteasome Subunits Involved in Neurodegenerative Diseases. Arch Med Res 2020; 52:1-14. [PMID: 32962866 DOI: 10.1016/j.arcmed.2020.09.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/25/2020] [Accepted: 09/04/2020] [Indexed: 12/29/2022]
Abstract
The ubiquitin-proteasome system is the major pathway for the maintenance of protein homeostasis. Its inhibition causes accumulation of ubiquitinated proteins; this accumulation has been associated with several of the most common neurodegenerative diseases. Several genetic factors have been identified for most neurodegenerative diseases, however, most cases are considered idiopathic, thus making the study of the mechanisms of protein accumulation a relevant field of research. It is often mentioned that the biggest risk factor for neurodegenerative diseases is aging, and several groups have reported an age-related alteration of the expression of some of the 26S proteasome subunits and a reduction of its activity. Proteasome subunits interact with proteins that are known to accumulate in neurodegenerative diseases such as α-synuclein in Parkinson's, tau in Alzheimer's, and huntingtin in Huntington's diseases. These interactions have been explored for several years, but only until recently, we are beginning to understand them. In this review, we discuss the known interactions, the underlying patterns, and the phenotypes associated with the 26S proteasome subunits in the etiology and progression of neurodegenerative diseases where there is evidence of proteasome involvement. Special emphasis is made in reviewing proteasome subunits that interact with proteins known to have an age-related altered expression or to be involved in neurodegenerative diseases to explore key effectors that may trigger or augment their progression. Interestingly, while the causes of age-related reduction of some of the proteasome subunits are not known, there are specific relationships between the observed neurodegenerative disease and the affected proteasome subunits.
Collapse
|
12
|
Fouka M, Mavroeidi P, Tsaka G, Xilouri M. In Search of Effective Treatments Targeting α-Synuclein Toxicity in Synucleinopathies: Pros and Cons. Front Cell Dev Biol 2020; 8:559791. [PMID: 33015057 PMCID: PMC7500083 DOI: 10.3389/fcell.2020.559791] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 08/14/2020] [Indexed: 12/11/2022] Open
Abstract
Parkinson's disease (PD), multiple system atrophy (MSA) and Dementia with Lewy bodies (DLB) represent pathologically similar, progressive neurodegenerative disorders characterized by the pathological aggregation of the neuronal protein α-synuclein. PD and DLB are characterized by the abnormal accumulation and aggregation of α-synuclein in proteinaceous inclusions within neurons named Lewy bodies (LBs) and Lewy neurites (LNs), whereas in MSA α-synuclein inclusions are mainly detected within oligodendrocytes named glial cytoplasmic inclusions (GCIs). The presence of pathologically aggregated α-synuclein along with components of the protein degradation machinery, such as ubiquitin and p62, in LBs and GCIs is considered to underlie the pathogenic cascade that eventually leads to the severe neurodegeneration and neuroinflammation that characterizes these diseases. Importantly, α-synuclein is proposed to undergo pathogenic misfolding and oligomerization into higher-order structures, revealing self-templating conformations, and to exert the ability of "prion-like" spreading between cells. Therefore, the manner in which the protein is produced, is modified within neural cells and is degraded, represents a major focus of current research efforts in the field. Given that α-synuclein protein load is critical to disease pathogenesis, the identification of means to limit intracellular protein burden and halt α-synuclein propagation represents an obvious therapeutic approach in synucleinopathies. However, up to date the development of effective therapeutic strategies to prevent degeneration in synucleinopathies is limited, due to the lack of knowledge regarding the precise mechanisms underlying the observed pathology. This review critically summarizes the recent developed strategies to counteract α-synuclein toxicity, including those aimed to increase protein degradation, to prevent protein aggregation and cell-to-cell propagation, or to engage antibodies against α-synuclein and discuss open questions and unknowns for future therapeutic approaches.
Collapse
Affiliation(s)
| | | | | | - Maria Xilouri
- Center of Clinical Research, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| |
Collapse
|
13
|
Limanaqi F, Biagioni F, Gambardella S, Familiari P, Frati A, Fornai F. Promiscuous Roles of Autophagy and Proteasome in Neurodegenerative Proteinopathies. Int J Mol Sci 2020; 21:E3028. [PMID: 32344772 PMCID: PMC7215558 DOI: 10.3390/ijms21083028] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 12/12/2022] Open
Abstract
Alterations in autophagy and the ubiquitin proteasome system (UPS) are commonly implicated in protein aggregation and toxicity which manifest in a number of neurological disorders. In fact, both UPS and autophagy alterations are bound to the aggregation, spreading and toxicity of the so-called prionoid proteins, including alpha synuclein (α-syn), amyloid-beta (Aβ), tau, huntingtin, superoxide dismutase-1 (SOD-1), TAR-DNA-binding protein of 43 kDa (TDP-43) and fused in sarcoma (FUS). Recent biochemical and morphological studies add to this scenario, focusing on the coordinated, either synergistic or compensatory, interplay that occurs between autophagy and the UPS. In fact, a number of biochemical pathways such as mammalian target of rapamycin (mTOR), transcription factor EB (TFEB), Bcl2-associated athanogene 1/3 (BAG3/1) and glycogen synthase kinase beta (GSk3β), which are widely explored as potential targets in neurodegenerative proteinopathies, operate at the crossroad between autophagy and UPS. These biochemical steps are key in orchestrating the specificity and magnitude of the two degradation systems for effective protein homeostasis, while intermingling with intracellular secretory/trafficking and inflammatory pathways. The findings discussed in the present manuscript are supposed to add novel viewpoints which may further enrich our insight on the complex interactions occurring between cell-clearing systems, protein misfolding and propagation. Discovering novel mechanisms enabling a cross-talk between the UPS and autophagy is expected to provide novel potential molecular targets in proteinopathies.
Collapse
Affiliation(s)
- Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy;
| | - Francesca Biagioni
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077 Pozzilli, Italy; (F.B.); (S.G.); (A.F.)
| | - Stefano Gambardella
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077 Pozzilli, Italy; (F.B.); (S.G.); (A.F.)
| | - Pietro Familiari
- Department of Human Neurosciences, Division of Neurosurgery, Sapienza University of Rome, 00185 Roma, Italy;
| | - Alessandro Frati
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077 Pozzilli, Italy; (F.B.); (S.G.); (A.F.)
| | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy;
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077 Pozzilli, Italy; (F.B.); (S.G.); (A.F.)
| |
Collapse
|
14
|
Teil M, Arotcarena ML, Faggiani E, Laferriere F, Bezard E, Dehay B. Targeting α-synuclein for PD Therapeutics: A Pursuit on All Fronts. Biomolecules 2020; 10:biom10030391. [PMID: 32138193 PMCID: PMC7175302 DOI: 10.3390/biom10030391] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/26/2020] [Accepted: 02/29/2020] [Indexed: 12/15/2022] Open
Abstract
Parkinson's Disease (PD) is characterized both by the loss of dopaminergic neurons in the substantia nigra and the presence of cytoplasmic inclusions called Lewy Bodies. These Lewy Bodies contain the aggregated α-synuclein (α-syn) protein, which has been shown to be able to propagate from cell to cell and throughout different regions in the brain. Due to its central role in the pathology and the lack of a curative treatment for PD, an increasing number of studies have aimed at targeting this protein for therapeutics. Here, we reviewed and discussed the many different approaches that have been studied to inhibit α-syn accumulation via direct and indirect targeting. These analyses have led to the generation of multiple clinical trials that are either completed or currently active. These clinical trials and the current preclinical studies must still face obstacles ahead, but give hope of finding a therapy for PD with time.
Collapse
Affiliation(s)
- Margaux Teil
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Marie-Laure Arotcarena
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Emilie Faggiani
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Florent Laferriere
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Erwan Bezard
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Benjamin Dehay
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
- Correspondence:
| |
Collapse
|
15
|
Pathways of protein synthesis and degradation in PD pathogenesis. PROGRESS IN BRAIN RESEARCH 2020; 252:217-270. [PMID: 32247365 DOI: 10.1016/bs.pbr.2020.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Since the discovery of protein aggregates in the brains of individuals with Parkinson's disease (PD) in the early 20th century, the scientific community has been interested in the role of dysfunctional protein metabolism in PD etiology. Recent advances in the field have implicated defective protein handling underlying PD through genetic, in vitro, and in vivo studies incorporating many disease models alongside neuropathological evidence. Here, we discuss the existing body of research focused on understanding cellular pathways of protein synthesis and degradation, and how aberrations in either system could engender PD pathology with special attention to α-synuclein-related consequences. We consider transcription, translation, and post-translational modification to constitute protein synthesis, and protein degradation to encompass proteasome-, lysosome- and endoplasmic reticulum-dependent mechanisms. Novel findings connecting each of these steps in protein metabolism to development of PD indicate that deregulation of protein production and turnover remains an exciting area in PD research.
Collapse
|
16
|
Lehtonen Š, Sonninen TM, Wojciechowski S, Goldsteins G, Koistinaho J. Dysfunction of Cellular Proteostasis in Parkinson's Disease. Front Neurosci 2019; 13:457. [PMID: 31133790 PMCID: PMC6524622 DOI: 10.3389/fnins.2019.00457] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/23/2019] [Indexed: 12/15/2022] Open
Abstract
Despite decades of research, current therapeutic interventions for Parkinson’s disease (PD) are insufficient as they fail to modify disease progression by ameliorating the underlying pathology. Cellular proteostasis (protein homeostasis) is an essential factor in maintaining a persistent environment for neuronal activity. Proteostasis is ensured by mechanisms including regulation of protein translation, chaperone-assisted protein folding and protein degradation pathways. It is generally accepted that deficits in proteostasis are linked to various neurodegenerative diseases including PD. While the proteasome fails to degrade large protein aggregates, particularly alpha-synuclein (α-SYN) in PD, drug-induced activation of autophagy can efficiently remove aggregates and prevent degeneration of dopaminergic (DA) neurons. Therefore, maintenance of these mechanisms is essential to preserve all cellular functions relying on a correctly folded proteome. The correlations between endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) that aims to restore proteostasis within the secretory pathway are well-established. However, while mild insults increase the activity of chaperones, prolonged cell stress, or insufficient adaptive response causes cell death. Modulating the activity of molecular chaperones, such as protein disulfide isomerase which assists refolding and contributes to the removal of unfolded proteins, and their associated pathways may offer a new approach for disease-modifying treatment. Here, we summarize some of the key concepts and emerging ideas on the relation of protein aggregation and imbalanced proteostasis with an emphasis on PD as our area of main expertise. Furthermore, we discuss recent insights into the strategies for reducing the toxic effects of protein unfolding in PD by targeting the ER UPR pathway.
Collapse
Affiliation(s)
- Šárka Lehtonen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Tuuli-Maria Sonninen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Sara Wojciechowski
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Gundars Goldsteins
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jari Koistinaho
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| |
Collapse
|
17
|
Stefanis L, Emmanouilidou E, Pantazopoulou M, Kirik D, Vekrellis K, Tofaris GK. How is alpha-synuclein cleared from the cell? J Neurochem 2019; 150:577-590. [PMID: 31069800 DOI: 10.1111/jnc.14704] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/04/2019] [Accepted: 04/05/2019] [Indexed: 12/22/2022]
Abstract
The levels and conformers of alpha-synuclein are critical in the pathogenesis of Parkinson's Disease and related synucleinopathies. Homeostatic mechanisms in protein degradation and secretion have been identified as regulators of alpha-synuclein at different stages of its intracellular trafficking and transcellular propagation. Here we review pathways involved in the removal of various forms of alpha-synuclein from both the intracellular and extracellular environment. Proteasomes and lysosomes are likely to play complementary roles in the removal of intracellular alpha-synuclein species, in a manner that depends on alpha-synuclein post-translational modifications. Extracellular alpha-synuclein is cleared by extracellular proteolytic enzymes, or taken up by neighboring cells, especially microglia and astrocytes, and degraded within lysosomes. Exosomes, on the other hand, represent a vehicle for egress of excess burden of the intracellular protein, potentially contributing to the transfer of alpha-synuclein between cells. Dysfunction in any one of these clearance mechanisms, or a combination thereof, may be involved in the initiation or progression of Parkinson's disease, whereas targeting these pathways may offer an opportunity for therapeutic intervention. This article is part of the Special Issue "Synuclein".
Collapse
Affiliation(s)
- Leonidas Stefanis
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece.,First Department of Neurology, National and Kapodistrian University of Athens Medical School, Athens, Greece
| | | | | | - Deniz Kirik
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Kostas Vekrellis
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - George K Tofaris
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| |
Collapse
|
18
|
Pathogenic alpha-synuclein aggregates preferentially bind to mitochondria and affect cellular respiration. Acta Neuropathol Commun 2019; 7:41. [PMID: 30871620 PMCID: PMC6419482 DOI: 10.1186/s40478-019-0696-4] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 03/10/2019] [Indexed: 11/10/2022] Open
Abstract
Misfolded alpha-synuclein (αSyn) is a major constituent of Lewy bodies and Lewy neurites, which are pathological hallmarks of Parkinson's disease (PD). The contribution of αSyn to PD is well established, but the detailed mechanism remains obscure. Using a model in which αSyn aggregation in primary neurons was seeded by exogenously added, preformed αSyn amyloid fibrils (PFF), we found that a majority of pathogenic αSyn (indicated by serine 129 phosphorylated αSyn, ps-αSyn) was membrane-bound and associated with mitochondria. In contrast, only a minuscule amount of physiological αSyn was mitochondrial bound. In vitro, αSyn PFF displayed a stronger binding to purified mitochondria than did αSyn monomer, revealing a preferential mitochondria binding by aggregated αSyn. This selective mitochondrial ps-αSyn accumulation was confirmed in other neuronal and animal αSyn aggregation models that do not require exogenously added PFF and, more importantly, in postmortem brain tissues of patients suffering from PD and other neurodegenerative diseases with αSyn aggregation (α-synucleinopathies). We also showed that the mitochondrial ps-αSyn accumulation was accompanied by defects in cellular respiration in primary neurons, suggesting a link to mitochondrial dysfunction. Together, our results show that, contrary to physiological αSyn, pathogenic αSyn aggregates preferentially bind to mitochondria, indicating mitochondrial dysfunction as the common downstream mechanism for α-synucleinopathies. Our findings suggest a plausible model explaining the formation and the peculiar morphology of Lewy body and reveal that disrupting the interaction between ps-αSyn and the mitochondria is a therapeutic target for α-synucleinopathies.
Collapse
|
19
|
Cresto N, Gardier C, Gubinelli F, Gaillard MC, Liot G, West AB, Brouillet E. The unlikely partnership between LRRK2 and α-synuclein in Parkinson's disease. Eur J Neurosci 2019; 49:339-363. [PMID: 30269383 PMCID: PMC6391223 DOI: 10.1111/ejn.14182] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 09/11/2018] [Accepted: 09/17/2018] [Indexed: 12/19/2022]
Abstract
Our understanding of the mechanisms underlying Parkinson's disease, the once archetypical nongenetic neurogenerative disorder, has dramatically increased with the identification of α-synuclein and LRRK2 pathogenic mutations. While α-synuclein protein composes the aggregates that can spread through much of the brain in disease, LRRK2 encodes a multidomain dual-enzyme distinct from any other protein linked to neurodegeneration. In this review, we discuss emergent datasets from multiple model systems that suggest these unlikely partners do interact in important ways in disease, both within cells that express both LRRK2 and α-synuclein as well as through more indirect pathways that might involve neuroinflammation. Although the link between LRRK2 and disease can be understood in part through LRRK2 kinase activity (phosphotransferase activity), α-synuclein toxicity is multilayered and plausibly interacts with LRRK2 kinase activity in several ways. We discuss common protein interactors like 14-3-3s that may regulate α-synuclein and LRRK2 in disease. Finally, we examine cellular pathways and outcomes common to both mutant α-synuclein expression and LRRK2 activity and points of intersection. Understanding the interplay between these two unlikely partners in disease may provide new therapeutic avenues for PD.
Collapse
Affiliation(s)
- Noémie Cresto
- Neurodegenerative Diseases Laboratory, UMR9199, CEA, CNRS, Université Paris Sud, Université Paris-Saclay, and MIRCen (Molecular Imaging Research Centre), Institut François Jacob, DRF, CEA, Fontenay-aux-Roses, France
| | - Camille Gardier
- Neurodegenerative Diseases Laboratory, UMR9199, CEA, CNRS, Université Paris Sud, Université Paris-Saclay, and MIRCen (Molecular Imaging Research Centre), Institut François Jacob, DRF, CEA, Fontenay-aux-Roses, France
| | - Francesco Gubinelli
- Neurodegenerative Diseases Laboratory, UMR9199, CEA, CNRS, Université Paris Sud, Université Paris-Saclay, and MIRCen (Molecular Imaging Research Centre), Institut François Jacob, DRF, CEA, Fontenay-aux-Roses, France
| | - Marie-Claude Gaillard
- Neurodegenerative Diseases Laboratory, UMR9199, CEA, CNRS, Université Paris Sud, Université Paris-Saclay, and MIRCen (Molecular Imaging Research Centre), Institut François Jacob, DRF, CEA, Fontenay-aux-Roses, France
| | - Géraldine Liot
- Neurodegenerative Diseases Laboratory, UMR9199, CEA, CNRS, Université Paris Sud, Université Paris-Saclay, and MIRCen (Molecular Imaging Research Centre), Institut François Jacob, DRF, CEA, Fontenay-aux-Roses, France
| | - Andrew B. West
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, United States 35294
| | - Emmanuel Brouillet
- Neurodegenerative Diseases Laboratory, UMR9199, CEA, CNRS, Université Paris Sud, Université Paris-Saclay, and MIRCen (Molecular Imaging Research Centre), Institut François Jacob, DRF, CEA, Fontenay-aux-Roses, France
| |
Collapse
|
20
|
LRRK2 G2019S Mutation Inhibits Degradation of α-Synuclein in an In Vitro Model of Parkinson's Disease. Curr Med Sci 2018; 38:1012-1017. [PMID: 30536063 DOI: 10.1007/s11596-018-1977-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 10/30/2018] [Indexed: 12/31/2022]
Abstract
The G2019S mutation of the leucine-rich repeat kinase 2 (LRRK2) is the most common genetic cause of Parkinson's disease (PD). However, the molecular mechanisms of LRRK2 mutation contributing to the onset and progression of PD have not been fully illustrated. We generated HEK293 cells stably transfected with α-synuclein and investigated the effect of LRRK2 G2019S mutation on the degradation of α-synuclein. The lysosomal activity was assessed by the protein degradation of glyceraldehyde-3-phosphate dehydrogenase and ribonuclease A. It was found that α-synuclein was mainly degraded in lysosomes. LRRK2 G2019S inhibited the degradation of α-synuclein, and promoted its aggregation. LRRK2 G2019S also decreased the activities of lysosomal enzymes including cathepsin B and cathepsin L. Furthermore, the inhibitory effect of LRRK2 G2019S on lysosomal functions did not depend on its kinase activity. These findings indicated that the inhibitory effect of LRRK2 G2019S on α-synuclein degradation could underlie the pathogenesis of aberrant α-synuclein aggregation in PD with LRRK2 mutation.
Collapse
|
21
|
Huang CC, Chiu TY, Lee TY, Hsieh HJ, Lin CC, Kao LS. Soluble α-synuclein facilitates priming and fusion by releasing Ca 2+ from the thapsigargin-sensitive Ca 2+ pool in PC12 cells. J Cell Sci 2018; 131:jcs.213017. [PMID: 30404828 DOI: 10.1242/jcs.213017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 10/12/2018] [Indexed: 02/01/2023] Open
Abstract
α-Synuclein is associated with Parkinson's disease, and is mainly localized in presynaptic terminals and regulates exocytosis, but its physiological roles remain controversial. Here, we studied the effects of soluble and aggregated α-synuclein on exocytosis, and explored the molecular mechanism by which α-synuclein interacts with regulatory proteins, including Rab3A, Munc13-1 (also known as Unc13a) and Munc18-1 (also known as STXBP1), in order to regulate exocytosis. Through fluorescence recovery after photobleaching experiments, overexpressed α-synuclein in PC12 cells was found to be in a monomeric form, which promotes exocytosis. In contrast, aggregated α-synuclein induced by lactacystin treatment inhibits exocytosis. Our results show that α-synuclein is involved in vesicle priming and fusion. α-Synuclein and phorbol 12-myristate 13-acetate (PMA), which is known to enhance vesicle priming mediated by Rab3A, Munc13-1 and Munc18-1, act on the same population of vesicles, but regulate priming independently. Furthermore, the results show a novel effects of α-synuclein on mobilizing Ca2+ release from thapsigargin-sensitive Ca2+ pools to enhance the ATP-induced [Ca2+]i increase, which enhances vesicle fusion. Our results provide a detailed understanding of the action of α-synuclein during the final steps of exocytosis.
Collapse
Affiliation(s)
- Chien-Chang Huang
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China.,Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Tai-Yu Chiu
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Tzu-Ying Lee
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Hsin-Jui Hsieh
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Chung-Chih Lin
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China .,Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China.,Biophotonics Interdisciplinary Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Lung-Sen Kao
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China .,Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| |
Collapse
|
22
|
Zeng Y, Jones AM, Thomas EE, Nassif B, Silberg JJ, Segatori L. A Split Transcriptional Repressor That Links Protein Solubility to an Orthogonal Genetic Circuit. ACS Synth Biol 2018; 7:2126-2138. [PMID: 30089365 PMCID: PMC6858789 DOI: 10.1021/acssynbio.8b00129] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Monitoring the aggregation of proteins within the cellular environment is key to investigating the molecular mechanisms underlying the formation of off-pathway protein assemblies associated with the development of disease and testing therapeutic strategies to prevent the accumulation of non-native conformations. It remains challenging, however, to couple protein aggregation events underlying the cellular pathogenesis of a disease to genetic circuits and monitor their progression in a quantitative fashion using synthetic biology tools. To link the aggregation propensity of a target protein to the expression of an easily detectable reporter, we investigated the use of a transcriptional AND gate system based on complementation of a split transcription factor. We first identified two-fragment tetracycline repressor (TetR) variants that can be regulated via ligand-dependent induction and demonstrated that split TetR variants can function as transcriptional AND gates in both bacteria and mammalian cells. We then adapted split TetR for use as an aggregation sensor. Protein aggregation was detected by monitoring complementation between a larger TetR fragment that serves as a "detector" and a smaller TetR fragment expressed as a fusion to an aggregation-prone protein that serves as a "sensor" of the target protein aggregation status. This split TetR represents a novel genetic component that can be used for a wide range of applications in bacterial as well as mammalian synthetic biology and a much needed cell-based sensor for monitoring a protein's conformational status in complex cellular environments.
Collapse
Affiliation(s)
- Yimeng Zeng
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, USA
| | - Alicia M. Jones
- Department of Biosciences, Rice University, Houston, Texas 77005, USA
| | - Emily E. Thomas
- Department of Biosciences, Rice University, Houston, Texas 77005, USA
| | - Barbara Nassif
- Department of Biosciences, Rice University, Houston, Texas 77005, USA
| | - Jonathan J. Silberg
- Department of Biosciences, Rice University, Houston, Texas 77005, USA
- Department of Bioengineering, Rice University, Houston, Texas 77005, USA
| | - Laura Segatori
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, USA
- Department of Biosciences, Rice University, Houston, Texas 77005, USA
- Department of Bioengineering, Rice University, Houston, Texas 77005, USA
| |
Collapse
|
23
|
Cox D, Raeburn C, Sui X, Hatters DM. Protein aggregation in cell biology: An aggregomics perspective of health and disease. Semin Cell Dev Biol 2018; 99:40-54. [PMID: 29753879 DOI: 10.1016/j.semcdb.2018.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 03/21/2018] [Accepted: 05/04/2018] [Indexed: 01/08/2023]
Abstract
Maintaining protein homeostasis (proteostasis) is essential for cellular health and is governed by a network of quality control machinery comprising over 800 genes. When proteostasis becomes imbalanced, proteins can abnormally aggregate or become mislocalized. Inappropriate protein aggregation and proteostasis imbalance are two of the central pathological features of common neurodegenerative diseases including Alzheimer, Parkinson, Huntington, and motor neuron diseases. How aggregation contributes to the pathogenic mechanisms of disease remains incompletely understood. Here, we integrate some of the key and emerging ideas as to how protein aggregation relates to imbalanced proteostasis with an emphasis on Huntington disease as our area of main expertise. We propose the term "aggregomics" be coined in reference to how aggregation of particular proteins concomitantly influences the spatial organization and protein-protein interactions of the surrounding proteome. Meta-analysis of aggregated interactomes from various published datasets reveals chaperones and RNA-binding proteins are common components across various disease contexts. We conclude with an examination of therapeutic avenues targeting proteostasis mechanisms.
Collapse
Affiliation(s)
- Dezerae Cox
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia
| | - Candice Raeburn
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia
| | - Xiaojing Sui
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia
| | - Danny M Hatters
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Australia; Bio21 Molecular Science and Biotechnology Institute, Australia.
| |
Collapse
|
24
|
Chung KM, Hernández N, Sproul AA, Yu WH. Alzheimer's disease and the autophagic-lysosomal system. Neurosci Lett 2018; 697:49-58. [PMID: 29758300 DOI: 10.1016/j.neulet.2018.05.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 05/08/2018] [Accepted: 05/10/2018] [Indexed: 02/06/2023]
Abstract
Age-related neurodegenerative diseases are of critical concern to the general population and research/medical community due to their health impact and socioeconomic consequences. A feature of most, if not all, neurodegenerative disorders is the presence of proteinopathies, in which misfolded or conformationally altered proteins drive disease progression and are often used as a primary neuropathological marker of disease. In particular, Alzheimer's disease (AD) is characterized by abnormal accumulation of protein aggregates, primarily extracellular plaques composed of the Aβ peptide and intracellular tangles comprised of the tau protein, both of which may indicate a primary defect in protein clearance. Protein degradation is a key cellular mechanism for protein homeostasis and is essential for cell survival but is disrupted in neurodegenerative diseases. Dysregulation in proteolytic pathways - mainly the autophagic-lysosomal system (A-LS) and the ubiquitin-proteasome system (UPS) - has been increasingly associated with proteinopathies in neurodegenerative diseases. Here we review the role of dysfunctional autophagy underlying AD-related proteinopathy and discuss how to model this aspect of disease, as well as summarize recent advances in translational strategies for targeted A-LS dysfunction in AD.
Collapse
Affiliation(s)
- Kyung Min Chung
- Taub Institute and the Department of Pathology & Cell Biology, Columbia University, New York, NY, 10032, United States
| | - Nancy Hernández
- Taub Institute and the Department of Pathology & Cell Biology, Columbia University, New York, NY, 10032, United States
| | - Andrew A Sproul
- Taub Institute and the Department of Pathology & Cell Biology, Columbia University, New York, NY, 10032, United States
| | - Wai Haung Yu
- Taub Institute and the Department of Pathology & Cell Biology, Columbia University, New York, NY, 10032, United States.
| |
Collapse
|
25
|
Oxidized DJ-1 Levels in Urine Samples as a Putative Biomarker for Parkinson's Disease. PARKINSONS DISEASE 2018; 2018:1241757. [PMID: 29887985 PMCID: PMC5985070 DOI: 10.1155/2018/1241757] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 03/25/2018] [Indexed: 12/29/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease. Oxidative stress is the most critical risk factor for neurodegenerative diseases, including Alzheimer's disease (AD) and Huntington's disease (HD). Numerous reports have demonstrated that oxidative stress aggravates cytotoxicity in dopaminergic neurons and accelerates the formation of protein inclusions. In addition, oxidative stress, such as 4-hydroxynonenal (HNE), oxidized protein, and dopamine quinone, are related to PD progression. DJ-1 is a PD-causative gene, and it plays a pivotal role as a sensor and eliminator of oxidative stress. Several studies have shown that oxidized DJ-1 (OxiDJ-1) formation is induced by oxidative stress. Hence, previous studies suggest that oxidized DJ-1 could be a biomarker for PD. We previously reported higher DJ-1 levels in Korean male PD patient urine exosomes than male non-PD controls. We speculate that OxiDJ-1 levels in PD patient urine might be higher than that in non-PD controls. In this study, we established an ELISA for OxiDJ-1 using recombinant DJ-1 treated with H2O2. Using Western blot assay and ELISA, we confirmed an increase of OxiDJ-1 from HEK293T cells treated with H2O2. Using our ELISA, we observed significantly higher, 2-fold, OxiDJ-1 levels in the urine of Korean PD patients than in non-PD controls.
Collapse
|
26
|
Frinchi M, Scaduto P, Cappello F, Belluardo N, Mudò G. Heat shock protein (Hsp) regulation by muscarinic acetylcholine receptor (mAChR) activation in the rat hippocampus. J Cell Physiol 2018; 233:6107-6116. [DOI: 10.1002/jcp.26454] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 12/04/2017] [Accepted: 01/02/2018] [Indexed: 12/30/2022]
Affiliation(s)
- Monica Frinchi
- Department of Experimental Biomedicine and Clinical Neuroscienc es, div. of Human PhysiologyUniversity of PalermoPalermoItaly
| | - Pietro Scaduto
- Department of Experimental Biomedicine and Clinical Neuroscienc es, div. of Human PhysiologyUniversity of PalermoPalermoItaly
| | - Francesco Cappello
- Department of Experimental Biomedicine and Clinical Neurosciences, div. of AnatomyUniversity of PalermoPalermoItaly
- Euro‐Mediterranean Institute of Science and TechnologyPalermoItaly
- Department of BiologyTemple UniversityPhiladelphiaPennsylvania
| | - Natale Belluardo
- Department of Experimental Biomedicine and Clinical Neuroscienc es, div. of Human PhysiologyUniversity of PalermoPalermoItaly
| | - Giuseppa Mudò
- Department of Experimental Biomedicine and Clinical Neuroscienc es, div. of Human PhysiologyUniversity of PalermoPalermoItaly
| |
Collapse
|
27
|
Terron A, Bal-Price A, Paini A, Monnet-Tschudi F, Bennekou SH, Leist M, Schildknecht S. An adverse outcome pathway for parkinsonian motor deficits associated with mitochondrial complex I inhibition. Arch Toxicol 2018; 92:41-82. [PMID: 29209747 PMCID: PMC5773657 DOI: 10.1007/s00204-017-2133-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 11/22/2017] [Indexed: 12/21/2022]
Abstract
Epidemiological studies have observed an association between pesticide exposure and the development of Parkinson's disease, but have not established causality. The concept of an adverse outcome pathway (AOP) has been developed as a framework for the organization of available information linking the modulation of a molecular target [molecular initiating event (MIE)], via a sequence of essential biological key events (KEs), with an adverse outcome (AO). Here, we present an AOP covering the toxicological pathways that link the binding of an inhibitor to mitochondrial complex I (i.e., the MIE) with the onset of parkinsonian motor deficits (i.e., the AO). This AOP was developed according to the Organisation for Economic Co-operation and Development guidelines and uploaded to the AOP database. The KEs linking complex I inhibition to parkinsonian motor deficits are mitochondrial dysfunction, impaired proteostasis, neuroinflammation, and the degeneration of dopaminergic neurons of the substantia nigra. These KEs, by convention, were linearly organized. However, there was also evidence of additional feed-forward connections and shortcuts between the KEs, possibly depending on the intensity of the insult and the model system applied. The present AOP demonstrates mechanistic plausibility for epidemiological observations on a relationship between pesticide exposure and an elevated risk for Parkinson's disease development.
Collapse
Affiliation(s)
| | | | - Alicia Paini
- European Commission Joint Research Centre, Ispra, Italy
| | | | | | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, PO Box M657, 78457, Konstanz, Germany
| | - Stefan Schildknecht
- In Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, PO Box M657, 78457, Konstanz, Germany.
| |
Collapse
|
28
|
Bentea E, Verbruggen L, Massie A. The Proteasome Inhibition Model of Parkinson's Disease. JOURNAL OF PARKINSONS DISEASE 2017; 7:31-63. [PMID: 27802243 PMCID: PMC5302045 DOI: 10.3233/jpd-160921] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The pathological hallmarks of Parkinson's disease are the progressive loss of nigral dopaminergic neurons and the formation of intracellular inclusion bodies, termed Lewy bodies, in surviving neurons. Accumulation of proteins in large insoluble cytoplasmic aggregates has been proposed to result, partly, from a failure in the function of intracellular protein degradation pathways. Evidence in support for such a hypothesis emerged in the beginning of the years 2000 with studies demonstrating structural and functional deficits in the ubiquitin-proteasome pathway in post-mortem nigral tissue of patients with Parkinson's disease. These fundamental findings have inspired the development of a new generation of animal models based on the use of proteasome inhibitors to disturb protein homeostasis and trigger nigral dopaminergic neurodegeneration. In this review, we provide an updated overview of the current approaches in employing proteasome inhibitors to model Parkinson's disease, with particular emphasis on rodent studies. In addition, the mechanisms underlying proteasome inhibition-induced cell death and the validity criteria (construct, face and predictive validity) of the model will be critically discussed. Due to its distinct, but highly relevant mechanism of inducing neuronal death, the proteasome inhibition model represents a useful addition to the repertoire of toxin-based models of Parkinson's disease that might provide novel clues to unravel the complex pathogenesis of this disorder.
Collapse
Affiliation(s)
| | | | - Ann Massie
- Correspondence to: Dr. Ann Massie, Department of Pharmaceutical Biotechnology and Molecular Biology, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium. Tel.: +32 2 477 4502; E-mail:
| |
Collapse
|
29
|
Gleixner AM, Hutchison DF, Sannino S, Bhatia TN, Leak LC, Flaherty PT, Wipf P, Brodsky JL, Leak RK. N-Acetyl-l-Cysteine Protects Astrocytes against Proteotoxicity without Recourse to Glutathione. Mol Pharmacol 2017; 92:564-575. [PMID: 28830914 DOI: 10.1124/mol.117.109926] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/17/2017] [Indexed: 02/06/2023] Open
Abstract
N-acetyl-l-cysteine (NAC) exhibits protective properties in brain injury models and has undergone a number of clinical trials. Most studies of NAC have focused on neurons. However, neuroprotection may be complemented by the protection of astrocytes because healthier astrocytes can better support the viability of neurons. Here, we show that NAC can protect astrocytes against protein misfolding stress (proteotoxicity), the hallmark of neurodegenerative disorders. Although NAC is thought to be a glutathione precursor, NAC protected primary astrocytes from the toxicity of the proteasome inhibitor MG132 without eliciting any increase in glutathione. Furthermore, glutathione depletion failed to attenuate the protective effects of NAC. MG132 elicited a robust increase in the folding chaperone heat shock protein 70 (Hsp70), and NAC mitigated this effect. Nevertheless, three independent inhibitors of Hsp70 function ablated the protective effects of NAC, suggesting that NAC may help preserve Hsp70 chaperone activity and improve protein quality control without need for Hsp70 induction. Consistent with this view, NAC abolished an increase in ubiquitinated proteins in MG132-treated astrocytes. However, NAC did not affect the loss of proteasome activity in response to MG132, demonstrating that it boosted protein homeostasis and cell viability without directly interfering with the efficacy of this proteasome inhibitor. The thiol-containing molecules l-cysteine and d-cysteine both mimicked the protective effects of NAC, whereas the thiol-lacking molecule N-acetyl-S-methyl-l-cysteine failed to exert protection or blunt the rise in ubiquitinated proteins. Collectively, these findings suggest that the thiol group in NAC is required for its effects on glial viability and protein quality control.
Collapse
Affiliation(s)
- Amanda M Gleixner
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Daniel F Hutchison
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Sara Sannino
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Tarun N Bhatia
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Lillian C Leak
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Patrick T Flaherty
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Peter Wipf
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Jeffrey L Brodsky
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| |
Collapse
|
30
|
Prion-like mechanisms and potential therapeutic targets in neurodegenerative disorders. Pharmacol Ther 2017; 172:22-33. [DOI: 10.1016/j.pharmthera.2016.11.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
31
|
Prolyl oligopeptidase inhibition attenuates the toxicity of a proteasomal inhibitor, lactacystin, in the alpha-synuclein overexpressing cell culture. Neurosci Lett 2017; 636:83-89. [DOI: 10.1016/j.neulet.2016.11.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 11/01/2016] [Accepted: 11/02/2016] [Indexed: 11/23/2022]
|
32
|
Gleixner AM, Posimo JM, Pant DB, Henderson MP, Leak RK. Astrocytes Surviving Severe Stress Can Still Protect Neighboring Neurons from Proteotoxic Injury. Mol Neurobiol 2016; 53:4939-60. [PMID: 26374549 PMCID: PMC4792804 DOI: 10.1007/s12035-015-9427-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 09/03/2015] [Indexed: 12/18/2022]
Abstract
Astrocytes are one of the major cell types to combat cellular stress and protect neighboring neurons from injury. In order to fulfill this important role, astrocytes must sense and respond to toxic stimuli, perhaps including stimuli that are severely stressful and kill some of the astrocytes. The present study demonstrates that primary astrocytes that managed to survive severe proteotoxic stress were protected against subsequent challenges. These findings suggest that the phenomenon of preconditioning or tolerance can be extended from mild to severe stress for this cell type. Astrocytic stress adaptation lasted at least 96 h, the longest interval tested. Heat shock protein 70 (Hsp70) was raised in stressed astrocytes, but inhibition of neither Hsp70 nor Hsp32 activity abolished their resistance against a second proteotoxic challenge. Only inhibition of glutathione synthesis abolished astrocytic stress adaptation, consistent with our previous report. Primary neurons were plated upon previously stressed astrocytes, and the cocultures were then exposed to another proteotoxic challenge. Severely stressed astrocytes were still able to protect neighboring neurons against this injury, and the protection was unexpectedly independent of glutathione synthesis. Stressed astrocytes were even able to protect neurons after simultaneous application of proteasome and Hsp70 inhibitors, which otherwise elicited synergistic, severe loss of neurons when applied together. Astrocyte-induced neuroprotection against proteotoxicity was not elicited with astrocyte-conditioned media, suggesting that physical cell-to-cell contacts may be essential. These findings suggest that astrocytes may adapt to severe stress so that they can continue to protect neighboring cell types from profound injury.
Collapse
Affiliation(s)
- Amanda M Gleixner
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Jessica M Posimo
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Deepti B Pant
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Matthew P Henderson
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, 407 Mellon Hall, 600 Forbes Avenue, Pittsburgh, PA, 15282, USA.
| |
Collapse
|
33
|
Heinemann SD, Posimo JM, Mason DM, Hutchison DF, Leak RK. Synergistic stress exacerbation in hippocampal neurons: Evidence favoring the dual-hit hypothesis of neurodegeneration. Hippocampus 2016; 26:980-94. [PMID: 26934478 DOI: 10.1002/hipo.22580] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2016] [Indexed: 12/21/2022]
Abstract
The dual-hit hypothesis of neurodegeneration states that severe stress sensitizes vulnerable cells to subsequent challenges so that the two hits are synergistic in their toxic effects. Although the hippocampus is vulnerable to a number of neurodegenerative disorders, there are no models of synergistic cell death in hippocampal neurons in response to combined proteotoxic and oxidative stressors, the two major characteristics of these diseases. Therefore, a relatively high-throughput dual-hit model of stress synergy was developed in primary hippocampal neurons. In order to increase the rigor of the study and strengthen the interpretations, three independent, unbiased viability assays were employed at multiple timepoints. Stress synergy was elicited when hippocampal neurons were treated with the proteasome inhibitor MG132 followed by exposure to the oxidative toxicant paraquat, but only after 48 h. MG132 and paraquat only elicited additive effects 24 h after the final hit and even loss of heat shock protein 70 activity and glutathione did not promote stress synergy at this early timepoint. Dual hits of MG132 elicited modest glutathione loss and slightly synergistic toxic effects 48 h after the second hit, but only at some concentrations and only according to two viability assays (metabolic fitness and cytoskeletal integrity). The thiol N-acetyl cysteine protected hippocampal neurons against dual MG132/MG132 hits but not dual MG132/paraquat hits. These findings support the view that proteotoxic and oxidative stress propel and propagate each other in hippocampal neurons, leading to synergistically toxic effects, but not as the default response and only after a delay. The neuronal stress synergy observed here lies in contrast to astrocytic responses to dual hits, because astrocytes that survive severe proteotoxic stress resist additional cell loss following second hits. In conclusion, a new model of hippocampal vulnerability was developed for the testing of therapies, because neuroprotective treatments that are effective against severe, synergistic stress are more likely to succeed in the clinic. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Scott D Heinemann
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Jessica M Posimo
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Daniel M Mason
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Daniel F Hutchison
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania
| |
Collapse
|
34
|
Roy A, Rangasamy SB, Kundu M, Pahan K. BPOZ-2 Gene Delivery Ameliorates Alpha-Synucleinopathy in A53T Transgenic Mouse Model of Parkinson's Disease. Sci Rep 2016; 6:22067. [PMID: 26916519 PMCID: PMC4768134 DOI: 10.1038/srep22067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 02/05/2016] [Indexed: 12/04/2022] Open
Abstract
Ankyrin-rich BTB/POZ domain containing protein-2 or BPOZ-2, a scaffold protein, has been recently shown to control the degradation of many biological proteins ranging from embryonic development to tumor progression. However, its role in the process of neuronal diseases has not been properly explored. Since, abnormal clearance of metabolic proteins contributes to the development of alpha-synuclein (α-syn) pathologies in Parkinson’s disease (PD), we are interested to explore if BPOZ-2 participates in the amelioration of α-syn in vivo in basal ganglia. Here we report that lentiviral administration of bpoz-2 gene indeed lowers the burden of α-syn in DA neurons in the nigra of A53T transgenic (A53T-Tg) mouse. Our detailed immunological analyses have shown that the overexpression of bpoz-2 dramatically improves both somatic and neuritic α-syn pathologies in the nigral DA neurons. Similarly, the specific ablation of bpoz-2 by lentiviral-shRNA stimulates the load of monomeric and polymeric forms of α-syn in the nigral DA neurons of A53T-Tg. While investigating the mechanism, we observed that BPOZ-2 was involved in a protein-protein association with PINK1 and therefore could stimulate PINK1-dependent autophagic clearance of α-syn. Our results have demonstrated that bpoz-2 gene delivery could have prospect in the amelioration of alpha-synucleinopathy in PD and other Lewy body diseases.
Collapse
Affiliation(s)
- Avik Roy
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Suresh Babu Rangasamy
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Madhuchhanda Kundu
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Kalipada Pahan
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA.,Division of Research and Development, Jesse Brown Veterans Affairs Medical Center, 820 South Darnen Avenue, Chicago, IL, USA
| |
Collapse
|
35
|
Hassan M, Selimovic D, Hannig M, Haikel Y, Brodell RT, Megahed M. Endoplasmic reticulum stress-mediated pathways to both apoptosis and autophagy: Significance for melanoma treatment. World J Exp Med 2015; 5:206-217. [PMID: 26618107 PMCID: PMC4655250 DOI: 10.5493/wjem.v5.i4.206] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/29/2015] [Accepted: 09/08/2015] [Indexed: 02/06/2023] Open
Abstract
Melanoma is the most aggressive form of skin cancer. Disrupted intracellular signaling pathways are responsible for melanoma's extraordinary resistance to current chemotherapeutic modalities. The pathophysiologic basis for resistance to both chemo- and radiation therapy is rooted in altered genetic and epigenetic mechanisms that, in turn, result in the impairing of cell death machinery and/or excessive activation of cell growth and survival-dependent pathways. Although most current melanoma therapies target mitochondrial dysregulation, there is increasing evidence that endoplasmic reticulum (ER) stress-associated pathways play a role in the potentiation, initiation and maintenance of cell death machinery and autophagy. This review focuses on the reliability of ER-associated pathways as therapeutic targets for melanoma treatment.
Collapse
|
36
|
Yap YW, Llanos RM, La Fontaine S, Cater MA, Beart PM, Cheung NS. Comparative Microarray Analysis Identifies Commonalities in Neuronal Injury: Evidence for Oxidative Stress, Dysfunction of Calcium Signalling, and Inhibition of Autophagy-Lysosomal Pathway. Neurochem Res 2015; 41:554-67. [PMID: 26318862 DOI: 10.1007/s11064-015-1666-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 07/14/2015] [Accepted: 07/14/2015] [Indexed: 12/21/2022]
Abstract
Mitochondrial dysfunction, ubiquitin-proteasomal system impairment and excitotoxicity occur during the injury and death of neurons in neurodegenerative conditions. The aim of this work was to elucidate the cellular mechanisms that are universally altered by these conditions. Through overlapping expression profiles of rotenone-, lactacystin- and N-methyl-D-aspartate-treated cortical neurons, we have identified three affected biological processes that are commonly affected; oxidative stress, dysfunction of calcium signalling and inhibition of the autophagic-lysosomal pathway. These data provides many opportunities for therapeutic intervention in neurodegenerative conditions, where mitochondrial dysfunction, proteasomal inhibition and excitotoxicity are evident.
Collapse
Affiliation(s)
- Yann Wan Yap
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia
| | - Roxana M Llanos
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia
| | - Sharon La Fontaine
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia.,Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Michael A Cater
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia
| | - Philip M Beart
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Nam Sang Cheung
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia.
| |
Collapse
|
37
|
De Rosa P, Marini ES, Gelmetti V, Valente EM. Candidate genes for Parkinson disease: Lessons from pathogenesis. Clin Chim Acta 2015; 449:68-76. [PMID: 26048192 DOI: 10.1016/j.cca.2015.04.042] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 04/23/2015] [Indexed: 01/06/2023]
Abstract
Parkinson disease (PD) is a multifactorial neurodegenerative disease characterized by the progressive loss of specific neuronal populations and accumulation of Lewy bodies in the brain, leading to motor and non-motor symptoms. In a small subset of patients, PD is dominantly or recessively inherited, while a number of susceptibility genetic loci have been identified through genome wide association studies. The discovery of genes mutated in PD and functional studies on their protein products have provided new insights into the molecular events leading to neurodegeneration, suggesting that few interconnected molecular pathways may be deranged in all forms of PD, triggering neuronal loss. Here, we summarize the most relevant findings implicating the main PD-related proteins in biological processes such as mitochondrial dysfunction, misfolded protein damage, alteration of cellular clearance systems, abnormal calcium handling and altered inflammatory response, which represent key targets for neuroprotection.
Collapse
Affiliation(s)
- Priscilla De Rosa
- IRCCS Casa Sollievo della Sofferenza, CSS-Mendel Institute, San Giovanni Rotondo, Italy
| | - Elettra Sara Marini
- IRCCS Casa Sollievo della Sofferenza, CSS-Mendel Institute, San Giovanni Rotondo, Italy; Dept. of Biological and Environmental Sciences, University of Messina, Messina, Italy
| | - Vania Gelmetti
- IRCCS Casa Sollievo della Sofferenza, CSS-Mendel Institute, San Giovanni Rotondo, Italy
| | - Enza Maria Valente
- IRCCS Casa Sollievo della Sofferenza, CSS-Mendel Institute, San Giovanni Rotondo, Italy; Section of Neurosciences, Dept. of Medicine and Surgery, University of Salerno, Salerno, Italy.
| |
Collapse
|
38
|
Kilpatrick K, Zeng Y, Hancock T, Segatori L. Genetic and chemical activation of TFEB mediates clearance of aggregated α-synuclein. PLoS One 2015; 10:e0120819. [PMID: 25790376 PMCID: PMC4366176 DOI: 10.1371/journal.pone.0120819] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 02/05/2015] [Indexed: 12/27/2022] Open
Abstract
Aggregation of α-synuclein (α-syn) is associated with the development of a number of neurodegenerative diseases, including Parkinson’s disease (PD). The formation of α-syn aggregates results from aberrant accumulation of misfolded α-syn and insufficient or impaired activity of the two main intracellular protein degradation systems, namely the ubiquitin-proteasome system and the autophagy-lysosomal pathway. In this study, we investigated the role of transcription factor EB (TFEB), a master regulator of the autophagy-lysosomal pathway, in preventing the accumulation of α-syn aggregates in human neuroglioma cells. We found that TFEB overexpression reduces the accumulation of aggregated α-syn by inducing autophagic clearance of α-syn. Furthermore, we showed that pharmacological activation of TFEB using 2-hydroxypropyl-β-cyclodextrin promotes autophagic clearance of aggregated α-syn. In summary, our findings demonstrate that TFEB modulates autophagic clearance of α-syn and suggest that pharmacological activation of TFEB is a promising strategy to enhance the degradation of α-syn aggregates.
Collapse
Affiliation(s)
- Kiri Kilpatrick
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, United States of America
| | - Yimeng Zeng
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, United States of America
| | - Tommy Hancock
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, United States of America
| | - Laura Segatori
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, United States of America
- Department of Bioengineering, Rice University, Houston, Texas, United States of America
- Department of Biochemistry and Cell Biology. Rice University, Houston, Texas, United States of America
- * E-mail:
| |
Collapse
|
39
|
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
|
40
|
Posimo JM, Weilnau JN, Gleixner AM, Broeren MT, Weiland NL, Brodsky JL, Wipf P, Leak RK. Heat shock protein defenses in the neocortex and allocortex of the telencephalon. Neurobiol Aging 2015; 36:1924-37. [PMID: 25771395 DOI: 10.1016/j.neurobiolaging.2015.02.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/30/2015] [Accepted: 02/11/2015] [Indexed: 11/18/2022]
Abstract
The telencephalic allocortex develops protein inclusions before the neocortex in many age-related proteinopathies. One major defense mechanism against proteinopathic stress is the heat shock protein (Hsp) network. We therefore contrasted Hsp defenses in stressed primary neocortical and allocortical cells. Neocortical neurons were more resistant to the proteasome inhibitor MG132 than neurons from 3 allocortical subregions: entorhinal cortex, piriform cortex, and hippocampus. However, allocortical neurons exhibited higher MG132-induced increases in Hsp70 and heat shock cognate 70 (Hsc70). MG132-treated allocortical neurons also exhibited greater levels of protein ubiquitination. Inhibition of Hsp70/Hsc70 activity synergistically exacerbated MG132 toxicity in allocortical neurons more than neocortical neurons, suggesting that the allocortex is more reliant on these Hsp defenses. In contrast, astrocytes harvested from the neocortex or allocortex did not differ in their response to Hsp70/Hsc70 inhibition. Consistent with the idea that chaperones are maximally engaged in allocortical neurons, an increase in Hsp70/Hsc70 activity was protective only in neocortical neurons. Finally, the levels of select Hsps were altered in the neocortex and allocortex in vivo with aging.
Collapse
Affiliation(s)
- Jessica M Posimo
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Justin N Weilnau
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Amanda M Gleixner
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Matthew T Broeren
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Nicole L Weiland
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, USA.
| |
Collapse
|
41
|
Falsone A, Falsone SF. Legal but lethal: functional protein aggregation at the verge of toxicity. Front Cell Neurosci 2015; 9:45. [PMID: 25741240 PMCID: PMC4332346 DOI: 10.3389/fncel.2015.00045] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 01/30/2015] [Indexed: 12/21/2022] Open
Abstract
Many neurodegenerative disorders are linked to irreversible protein aggregation, a process that usually comes along with toxicity and serious cellular damage. However, it is emerging that protein aggregation can also serve for physiological purposes, as impressively shown for prions. While the aggregation of this protein family was initially considered exclusively toxic in mammalians organisms, it is now almost clear that many other proteins adopt prion-like attributes to rationally polymerize into higher order complexes with organized physiologic roles. This implies that cells can tolerate at least in some measure the accumulation of inherently dangerous protein aggregates for functional profit. This review summarizes currently known strategies that living organisms adopt to preserve beneficial aggregation, and to prevent the catastrophic accumulation of toxic aggregates that frequently accompany neurodegeneration.
Collapse
Affiliation(s)
- Angelika Falsone
- Institute of Pharmaceutical Sciences, University of Graz Graz, Austria
| | - S Fabio Falsone
- Institute of Pharmaceutical Sciences, University of Graz Graz, Austria
| |
Collapse
|
42
|
Konieczny J, Czarnecka A, Kamińska K, Lenda T, Nowak P. Decreased behavioral response to intranigrally administered GABAA agonist muscimol in the lactacystin model of Parkinson's disease may result from partial lesion of nigral non-dopamine neurons: comparison to the classical neurotoxin 6-OHDA. Behav Brain Res 2015; 283:203-14. [PMID: 25655509 DOI: 10.1016/j.bbr.2015.01.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 01/22/2015] [Accepted: 01/24/2015] [Indexed: 12/28/2022]
Abstract
Lactacystin is a selective UPS inhibitor recently used to destroy dopamine (DA) neurons in animal models of Parkinson's disease (PD). However, both in vitro and in vivo studies show discrepancies in terms of the sensitivity of non-DA neurons to its toxicity. Therefore, our study was aimed to examine the toxic effect of intranigral administration of lactacystin on DA and non-DA neurons in the rat substantia nigra (SN), compared to the classic neurotoxin 6-OHDA. Tissue DA levels in the striatum and SN and GABA levels in the SN were also examined. Moreover, behavioral response of nigral GABAA receptors to locally administered muscimol was evaluated in these two PD models. We found that both lactacystin and 6-OHDA induced a strong decrease in DA level in the lesioned striatum and SN but only lactacystin slightly reduced GABA levels in the SN. A stereological analysis showed that both neurotoxins highly decreased the number of DA neurons in the SN, while only lactacystin moderately reduced the number of non-DA ones. Finally, in the lactacystin group, the number of contralateral rotations after intranigrally administrated muscimol was decreased in contrast to the increased response in the 6-OHDA model. Our study proves that, although lactacystin is not a fully selective to DA neurons, these neurons are much more vulnerable to its toxicity. Partial lesion of nigral non-DA neurons in this model may explain the decreased behavioral response to the GABAA agonist muscimol.
Collapse
Affiliation(s)
- Jolanta Konieczny
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland.
| | - Anna Czarnecka
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland
| | - Kinga Kamińska
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland
| | - Tomasz Lenda
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland
| | - Przemysław Nowak
- Department of Toxicology and Occupational Health Protection, Medical University of Silesia, 18 Medyków Street, 40-752 Katowice Ligota, Poland
| |
Collapse
|
43
|
Licker V, Burkhard PR. Proteomics as a new paradigm to tackle Parkinson’s disease research challenges. TRANSLATIONAL PROTEOMICS 2014. [DOI: 10.1016/j.trprot.2014.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
44
|
Macedo D, Tavares L, McDougall GJ, Vicente Miranda H, Stewart D, Ferreira RB, Tenreiro S, Outeiro TF, Santos CN. (Poly)phenols protect from α-synuclein toxicity by reducing oxidative stress and promoting autophagy. Hum Mol Genet 2014; 24:1717-32. [DOI: 10.1093/hmg/ddu585] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
|
45
|
Konieczny J, Jantas D, Lenda T, Domin H, Czarnecka A, Kuter K, Śmiałowska M, Lasoń W, Lorenc-Koci E. Lack of neuroprotective effect of celastrol under conditions of proteasome inhibition by lactacystin in in vitro and in vivo studies: implications for Parkinson's disease. Neurotox Res 2014; 26:255-73. [PMID: 24842651 PMCID: PMC4143605 DOI: 10.1007/s12640-014-9477-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 04/11/2014] [Accepted: 05/03/2014] [Indexed: 01/23/2023]
Abstract
A number of studies suggest that the ubiquitin-proteasome system (UPS) impairment may underlie neuronal death in Parkinson's disease. Celastrol is a neuroprotective agent with anti-inflammatory and antioxidant properties. The aim of this study was to determine whether celastrol may exert neuroprotective effects both in vitro and in vivo under conditions of the lactacystin-induced UPS inhibition. In the in vitro study, mouse primary cortical neurons and neuroblastoma SH-SY5Y cells were incubated with lactacystin for 48 h (2.5 and 10 μg/ml, respectively). The animal study was performed on male Wistar rats injected unilaterally with lactacystin (5 μg/2 μl) into the substantia nigra (SN) pars compacta. In the in vitro study, we did not found any protective effects of celastrol, given either in the pre- or co-treatment mode. Moreover, in the higher concentrations, celastrol itself reduced cell viability, and enhanced the lactacystin-induced cell death in both types of cells. In the in vivo study, none of the celastrol doses (0.3-3 mg/kg) attenuated the lactacystin-induced decrease in the level of dopamine (DA) and its metabolites or protected nigral dopaminergic neurons against the lactacystin-induced degeneration. The highest celastrol dose potentiated the lactacystin-induced decrease in the level of DA and its metabolites in the lesioned striatum, and accelerated the lactacystin-induced increase in the oxidative and total metabolism of DA. Moreover, when given alone, this dose of celastrol bilaterally decreased the number and/or density of dopaminergic neurons in the SN. Our results demonstrate that celastrol does not induce neuroprotective effects under conditions of UPS inhibition.
Collapse
Affiliation(s)
- Jolanta Konieczny
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 St., 31-343, Kraków, Poland,
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Hu X, Zhang H, Zhang Y, Zhang Y, Bai L, Chen Q, Wu J, Zhang L. Differential protein profile of PC12 cells exposed to proteasomal inhibitor lactacystin. Neurosci Lett 2014; 575:25-30. [PMID: 24858133 DOI: 10.1016/j.neulet.2014.05.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 04/09/2014] [Accepted: 05/13/2014] [Indexed: 12/23/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide and recent studies implicate a central role for ubiquitin-proteasome system (UPS) impairment in the etiopathogenesis of PD. To explore the possible role of UPS dysfunction in PD and the proteins involved, PC12 cells were treated with 10μM lactacystin, a 20S proteasome inhibitor, for 24h. Lactacystin induced cell death and α-synuclein-positive inclusions in cytoplasm. Following two-dimensional difference in-gel electrophoresis (2-D DIGE) which was used to separate the cellular proteins, the proteins that were significantly altered were analyzed and identified. Proteomic study identified 6 differentially expressed proteins between lactacystin-treated and control cells in this study. Four proteins (heat shock 70kDa protein 8, 78kDa glucose-regulated protein, serine proteinase inhibitor clade B member 6 and aldehyde reductase) were increased and 2 proteins (peripherin and tyrosine hydroxylase) were decreased following proteasomal inhibition. The results revealed that PC12 cells treated with 10μM lactacystin for 24h could be used as a cellular model of PD. The proteins identified in the present indicate not only the damage of proteasomal inhibition to the cells but also the possible responses of the cells. These data show that proteomic study may provide information relevant to biological basis for PD and potential new treatment targets.
Collapse
Affiliation(s)
- Xinyu Hu
- Department of Neurology, The First Hospital, Jilin University, Changchun 130021, China
| | - Haina Zhang
- Department of Rehabilitation, The Second Hospital, Jilin University, Changchun 130041, China
| | - Yizhi Zhang
- Department of Neurology, The Second Hospital, Jilin University, Changchun 130041, China
| | - Ying Zhang
- Department of Neurology, The Second Hospital, Jilin University, Changchun 130041, China
| | - Ling Bai
- Department of Clinical Medicine, Norman Bethune Health Science Center, Jilin University, Changchun 130021, China
| | - Qiuhui Chen
- Department of Neurology, The Second Hospital, Jilin University, Changchun 130041, China
| | - Jiang Wu
- Department of Neurology, The First Hospital, Jilin University, Changchun 130021, China
| | - Lei Zhang
- Department of Pediatrics, The Second Hospital, Jilin University, Changchun 130041, China.
| |
Collapse
|
47
|
Huang H, Wang H, Figueiredo-Pereira ME. Regulating the ubiquitin/proteasome pathway via cAMP-signaling: neuroprotective potential. Cell Biochem Biophys 2014; 67:55-66. [PMID: 23686612 DOI: 10.1007/s12013-013-9628-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The cAMP-signaling pathway has been under intensive investigation for decades. It is a wonder that such a small simple molecule like cAMP can modulate a vast number of diverse processes in different types of cells. The ubiquitous involvement of cAMP-signaling in a variety of cellular events requires tight spatial and temporal control of its generation, propagation, compartmentalization, and elimination. Among the various steps of the cAMP-signaling pathway, G-protein-coupled receptors, adenylate cyclases, phosphodiesterases, the two major cAMP targets, i.e., protein kinase A and exchange protein activated by cAMP, as well as the A-kinase anchoring proteins, are potential targets for drug development. Herein we review the recent progress on the regulation and manipulation of different steps of the cAMP-signaling pathway. We end by focusing on the emerging role of cAMP-signaling in modulating protein degradation via the ubiquitin/proteasome pathway. New discoveries on the regulation of the ubiquitin/proteasome pathway by cAMP-signaling support the development of new therapeutic approaches to prevent proteotoxicity in chronic neurodegenerative disorders and other human disease conditions associated with impaired protein turnover by the ubiquitin/proteasome pathway and the accumulation of ubiquitin-protein aggregates.
Collapse
Affiliation(s)
- He Huang
- Department of Biological Sciences, Hunter College and Graduate Center, City University of New York, 695 Park Avenue, New York, NY 10065, USA
| | | | | |
Collapse
|
48
|
Konieczny J, Czarnecka A, Lenda T, Kamińska K, Lorenc-Koci E. Chronic L-DOPA treatment attenuates behavioral and biochemical deficits induced by unilateral lactacystin administration into the rat substantia nigra. Behav Brain Res 2013; 261:79-88. [PMID: 24361083 DOI: 10.1016/j.bbr.2013.12.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 12/05/2013] [Accepted: 12/11/2013] [Indexed: 12/25/2022]
Abstract
The aim of the study was to determine whether the dopamine (DA) precursor l-DOPA attenuates parkinsonian-like symptoms produced by the ubiquitin-proteasome system inhibitor lactacystin. Wistar rats were injected unilaterally with lactacystin (2.5 μg/2 μl) or 6-OHDA (8 μg/2 μl) into the substantia nigra (SN) pars compacta. Four weeks after the lesion, the animals were treated chronically with l-DOPA (25 or 50 mg/kg) for two weeks. During l-DOPA treatment, the lactacystin-treated rats were tested for catalepsy and forelimb asymmetry. Rotational behavior was evaluated after apomorphine (0.25 mg/kg) and l-DOPA in both PD models. After completion of experiments, the animals were killed and the levels of DA and its metabolites in the striatum and SN were assayed. We found that acute l-DOPA administration effectively decreased catalepsy and increased the use of the compromised forelimb in the cylinder test. However, the lactacystin group did not respond to apomorphine or acute l-DOPA administration in the rotational test. Repeated l-DOPA treatment produced contralateral rotations in both PD models, but the number of rotations was much greater in the 6-OHDA-lesioned rats. Both toxins markedly (>90%) reduced the levels of DA and its metabolites in the striatum and SN, while l-DOPA diminished these decreases, especially in the SN. By demonstrating the efficacy of l-DOPA in several behavioral tests, our study confirms the usefulness of the lactacystin lesion as a model of PD. However, marked differences in the rotational response to apomorphine and l-DOPA suggest different mechanisms of neurodegeneration evoked by lactacystin and 6-OHDA.
Collapse
Affiliation(s)
- Jolanta Konieczny
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 Street, PL 31-343 Kraków, Poland.
| | - Anna Czarnecka
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 Street, PL 31-343 Kraków, Poland
| | - Tomasz Lenda
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 Street, PL 31-343 Kraków, Poland
| | - Kinga Kamińska
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 Street, PL 31-343 Kraków, Poland
| | - Elżbieta Lorenc-Koci
- Department of Neuropsychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 Street, PL 31-343 Kraków, Poland
| |
Collapse
|
49
|
N-Acetyl cysteine blunts proteotoxicity in a heat shock protein-dependent manner. Neuroscience 2013; 255:19-32. [DOI: 10.1016/j.neuroscience.2013.09.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/11/2013] [Accepted: 09/25/2013] [Indexed: 11/23/2022]
|
50
|
Pienaar IS, Harrison IF, Elson JL, Bury A, Woll P, Simon AK, Dexter DT. An animal model mimicking pedunculopontine nucleus cholinergic degeneration in Parkinson's disease. Brain Struct Funct 2013; 220:479-500. [PMID: 24292256 DOI: 10.1007/s00429-013-0669-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/29/2013] [Indexed: 11/28/2022]
Abstract
A rostral brainstem structure, the pedunculopontine nucleus (PPN), is severely affected by Parkinson's disease (PD) pathology and is regarded a promising target for therapeutic deep-brain stimulation (DBS). However, understanding the PPN's role in PD and assessing the potential of DBS are hampered by the lack of a suitable model of PPN degeneration. Rats were rendered Parkinsonian through a unilateral substantia nigra pars compacta (SNpc) stereotaxic injection of the proteasome inhibitor Lactacystin, to investigate whether the lesion's pathological effects spread to impact the integrity of PPN cholinergic neurons which are affected in PD. At 5 weeks post-surgery, stereological analysis revealed that the lesion caused a 48 % loss of dopaminergic SNpc neurons and a 61 % loss of PPN cholinergic neurons, accompanied by substantial somatic hypotrophy in the remaining cholinergic neurons. Magnetic resonance imaging revealed T2 signal hyper-/hypointensity in the PPN of the injected hemisphere, respectively at weeks 3 and 5 post-lesion. Moreover, isolated PPN cholinergic neurons revealed no significant alterations in key autophagy mRNA levels, suggesting that autophagy-related mechanisms fail to protect the PPN against Lactacystin-induced cellular changes. Hence, the current results suggest that the Lactacystin PD model offers a suitable model for investigating the role of the PPN in PD.
Collapse
Affiliation(s)
- Ilse S Pienaar
- Division of Brain Sciences, Department of Medicine, Centre for Neuroinflammation and Neurodegeneration, Imperial College London, London, W12 ONN, UK,
| | | | | | | | | | | | | |
Collapse
|