251
|
Castonguay AM, Gravel C, Lévesque M. Treating Parkinson's Disease with Antibodies: Previous Studies and Future Directions. JOURNAL OF PARKINSONS DISEASE 2021; 11:71-92. [PMID: 33104039 PMCID: PMC7990466 DOI: 10.3233/jpd-202221] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Parkinson's disease is a neurodegenerative disorder mainly characterized by the degeneration of dopaminergic neurons in the substantia nigra. Degenerating neurons contain abnormal aggregates called Lewy bodies, that are predominantly composed of the misfolded and/or mutated alpha-synuclein protein. Post-translational modifications, cellular stress, inflammation and gene mutations are thought to trigger its pathological misfolding and aggregation. With alpha-synuclein pathology being strongly associated with dopaminergic neuronal toxicity, strategies aimed to reduce its burden are expected to be beneficial in slowing disease progression. Moreover, multiple sources of evidence suggest a cell-to-cell transmission of pathological alpha-synuclein in a prion-like manner. Therefore, antibodies targeting extra- or intracellular alpha-synuclein could be efficient in limiting the aggregation and transmission. Several active and passive immunization strategies have been explored to target alpha-synuclein. Here, we summarize immunotherapeutic approaches that were tested in pre-clinical or clinical studies in the last two decades in an attempt to treat Parkinson's disease.
Collapse
Affiliation(s)
- Anne-Marie Castonguay
- Department of Psychiatry and Neurosciences, Faculty of Medicine, Université Laval, Québec, QC, Canada.,CERVO Brain Research Centre, 2601, chemin de la Canardière, Québec, QC, Canada
| | - Claude Gravel
- Department of Psychiatry and Neurosciences, Faculty of Medicine, Université Laval, Québec, QC, Canada.,CERVO Brain Research Centre, 2601, chemin de la Canardière, Québec, QC, Canada
| | - Martin Lévesque
- Department of Psychiatry and Neurosciences, Faculty of Medicine, Université Laval, Québec, QC, Canada.,CERVO Brain Research Centre, 2601, chemin de la Canardière, Québec, QC, Canada
| |
Collapse
|
252
|
Plaza-Zabala A, Sierra-Torre V, Sierra A. Assessing Autophagy in Microglia: A Two-Step Model to Determine Autophagosome Formation, Degradation, and Net Turnover. Front Immunol 2021; 11:620602. [PMID: 33584716 PMCID: PMC7878397 DOI: 10.3389/fimmu.2020.620602] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 12/11/2020] [Indexed: 12/22/2022] Open
Abstract
Autophagy is a complex process that encompasses the enclosure of cytoplasmic debris or dysfunctional organelles in membranous vesicles, the autophagosomes, for their elimination in the lysosomes. Autophagy is increasingly recognized as a critical process in macrophages, including microglia, as it finely regulates innate immune functions such as inflammation. A gold-standard method to assess its induction is the analysis of the autophagic flux using as a surrogate the expression of the microtubule-associated light chain protein 3 conjugated to phosphatidylethanolamine (LC3-II) by Western blot, in the presence of lysosomal inhibitors. Therefore, the current definition of autophagy flux actually puts the focus on the degradation stage of autophagy. In contrast, the most important autophagy controlling genes that have been identified in the last few years in fact target early stages of autophagosome formation. From a biological standpoint is therefore conceivable that autophagosome formation and degradation are independently regulated and we argue that both stages need to be systematically analyzed. Here, we propose a simple two-step model to understand changes in autophagosome formation and degradation using data from conventional LC3-II Western blot, and test it using two models of autophagy modulation in cultured microglia: rapamycin and the ULK1/2 inhibitor, MRT68921. Our two-step model will help to unravel the effect of genetic, pharmacological, and environmental manipulations on both formation and degradation of autophagosomes, contributing to dissect out the role of autophagy in physiology and pathology in microglia as well as other cell types.
Collapse
Affiliation(s)
- Ainhoa Plaza-Zabala
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Spain.,Glial Cell Biology Lab, Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Virginia Sierra-Torre
- Glial Cell Biology Lab, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neuroscience, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Amanda Sierra
- Glial Cell Biology Lab, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neuroscience, University of the Basque Country UPV/EHU, Leioa, Spain.,Ikerbasque Foundation, Bilbao, Spain
| |
Collapse
|
253
|
Metabotropic glutamate receptor 5 inhibits α-synuclein-induced microglia inflammation to protect from neurotoxicity in Parkinson's disease. J Neuroinflammation 2021; 18:23. [PMID: 33461598 PMCID: PMC7814625 DOI: 10.1186/s12974-021-02079-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 01/07/2021] [Indexed: 12/19/2022] Open
Abstract
Background Microglia activation induced by α-synuclein (α-syn) is one of the most important factors in Parkinson’s disease (PD) pathogenesis. However, the molecular mechanisms by which α-syn exerts neuroinflammation and neurotoxicity remain largely elusive. Targeting metabotropic glutamate receptor 5 (mGluR5) has been an attractive strategy to mediate microglia activation for neuroprotection, which might be an essential regulator to modulate α-syn-induced neuroinflammation for the treatment of PD. Here, we showed that mGluR5 inhibited α-syn-induced microglia inflammation to protect from neurotoxicity in vitro and in vivo. Methods Co-immunoprecipitation assays were utilized to detect the interaction between mGluR5 and α-syn in microglia. Griess, ELISA, real-time PCR, western blotting, and immunofluorescence assays were used to detect the regulation of α-syn-induced inflammatory signaling, cytokine secretion, and lysosome-dependent degradation. Results α-syn selectively interacted with mGluR5 but not mGluR3, and α-syn N terminal deletion region was essential for binding to mGluR5 in co-transfected HEK293T cells. The interaction between these two proteins was further detected in BV2 microglia, which was inhibited by the mGluR5 specific agonist CHPG without effect by its selective antagonist MTEP. Moreover, in both BV2 cells and primary microglia, activation of mGluR5 by CHPG partially inhibited α-syn-induced inflammatory signaling and cytokine secretion and also inhibited the microglia activation to protect from neurotoxicity. We further found that α-syn overexpression decreased mGluR5 expression via a lysosomal pathway, as evidenced by the lysosomal inhibitor, NH4Cl, by blocking mGluR5 degradation, which was not evident with the proteasome inhibitor, MG132. Additionally, co-localization of mGluR5 with α-syn was detected in lysosomes as merging with its marker, LAMP-1. Consistently, in vivo experiments with LPS- or AAV-α-syn-induced rat PD model also confirmed that α-syn accelerated lysosome-dependent degradation of mGluR5 involving a complex, to regulate neuroinflammation. Importantly, the binding is strengthened with LPS or α-syn overexpression but alleviated by urate, a potential clinical biomarker for PD. Conclusions These findings provided evidence for a novel mechanism by which the association of α-syn with mGluR5 was attributed to α-syn-induced microglia activation via modulation of mGluR5 degradation and its intracellular signaling. This may be a new molecular target for an effective therapeutic strategy for PD pathology. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02079-1.
Collapse
|
254
|
Microglial Turnover in Ageing-Related Neurodegeneration: Therapeutic Avenue to Intervene in Disease Progression. Cells 2021; 10:cells10010150. [PMID: 33466587 PMCID: PMC7828713 DOI: 10.3390/cells10010150] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/11/2021] [Accepted: 01/11/2021] [Indexed: 02/06/2023] Open
Abstract
Microglia are brain-dwelling macrophages and major parts of the neuroimmune system that broadly contribute to brain development, homeostasis, ageing and injury repair in the central nervous system (CNS). Apart from other brain macrophages, they have the ability to constantly sense changes in the brain’s microenvironment, functioning as housekeepers for neuronal well-being and providing neuroprotection in normal physiology. Microglia use a set of genes for these functions that involve proinflammatory cytokines. In response to specific stimuli, they release these proinflammatory cytokines, which can damage and kill neurons via neuroinflammation. However, alterations in microglial functioning are a common pathophysiology in age-related neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, Huntington’s and prion diseases, as well as amyotrophic lateral sclerosis, frontotemporal dementia and chronic traumatic encephalopathy. When their sentinel or housekeeping functions are severely disrupted, they aggravate neuropathological conditions by overstimulating their defensive function and through neuroinflammation. Several pathways are involved in microglial functioning, including the Trem2, Cx3cr1 and progranulin pathways, which keep the microglial inflammatory response under control and promote clearance of injurious stimuli. Over time, an imbalance in this system leads to protective microglia becoming detrimental, initiating or exacerbating neurodegeneration. Correcting such imbalances might be a potential mode of therapeutic intervention in neurodegenerative diseases.
Collapse
|
255
|
Schmidt MF, Gan ZY, Komander D, Dewson G. Ubiquitin signalling in neurodegeneration: mechanisms and therapeutic opportunities. Cell Death Differ 2021; 28:570-590. [PMID: 33414510 PMCID: PMC7862249 DOI: 10.1038/s41418-020-00706-7] [Citation(s) in RCA: 181] [Impact Index Per Article: 60.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 12/01/2020] [Accepted: 12/01/2020] [Indexed: 02/06/2023] Open
Abstract
Neurodegenerative diseases are characterised by progressive damage to the nervous system including the selective loss of vulnerable populations of neurons leading to motor symptoms and cognitive decline. Despite millions of people being affected worldwide, there are still no drugs that block the neurodegenerative process to stop or slow disease progression. Neuronal death in these diseases is often linked to the misfolded proteins that aggregate within the brain (proteinopathies) as a result of disease-related gene mutations or abnormal protein homoeostasis. There are two major degradation pathways to rid a cell of unwanted or misfolded proteins to prevent their accumulation and to maintain the health of a cell: the ubiquitin–proteasome system and the autophagy–lysosomal pathway. Both of these degradative pathways depend on the modification of targets with ubiquitin. Aging is the primary risk factor of most neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis. With aging there is a general reduction in proteasomal degradation and autophagy, and a consequent increase of potentially neurotoxic protein aggregates of β-amyloid, tau, α-synuclein, SOD1 and TDP-43. An often over-looked yet major component of these aggregates is ubiquitin, implicating these protein aggregates as either an adaptive response to toxic misfolded proteins or as evidence of dysregulated ubiquitin-mediated degradation driving toxic aggregation. In addition, non-degradative ubiquitin signalling is critical for homoeostatic mechanisms fundamental for neuronal function and survival, including mitochondrial homoeostasis, receptor trafficking and DNA damage responses, whilst also playing a role in inflammatory processes. This review will discuss the current understanding of the role of ubiquitin-dependent processes in the progressive loss of neurons and the emergence of ubiquitin signalling as a target for the development of much needed new drugs to treat neurodegenerative disease. ![]()
Collapse
Affiliation(s)
- Marlene F Schmidt
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Royal Parade, Melbourne, VIC, 3052, Australia
| | - Zhong Yan Gan
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Royal Parade, Melbourne, VIC, 3052, Australia
| | - David Komander
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Royal Parade, Melbourne, VIC, 3052, Australia
| | - Grant Dewson
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Royal Parade, Melbourne, VIC, 3052, Australia.
| |
Collapse
|
256
|
Carlson SW, Yan HQ, Li Y, Henchir J, Ma X, Young MS, Ikonomovic MD, Dixon CE. Differential Regional Responses in Soluble Monomeric Alpha Synuclein Abundance Following Traumatic Brain Injury. Mol Neurobiol 2021; 58:362-374. [PMID: 32948930 PMCID: PMC7704579 DOI: 10.1007/s12035-020-02123-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/05/2020] [Indexed: 12/14/2022]
Abstract
Alpha synuclein (α-synuclein) is a neuronal protein found predominately in presynaptic terminals. While the pathological effect of α-synuclein aggregates has been a topic of intense study in several neurodegenerative conditions, less attention has been placed on changes in monomeric α-synuclein and related physiological consequences on neuronal function. A growing body of evidence supports an important physiological role of α-synuclein in neurotransmission. In the context of traumatic brain injury (TBI), we hypothesized that the regional abundance of soluble monomeric α-synuclein is altered over a chronic time period post-injury. To this end, we evaluated α-synuclein in the cortex, hippocampus, and striatum of adult rats at 6 h, 1 day, 1, 2, 4, and 8 weeks after controlled cortical impact (CCI) injury. Western blot analysis demonstrated decreased levels of monomer α-synuclein protein in the ipsilateral hippocampus at 6 h, 1 day, 1, 2, and 8 weeks, as well as in the ipsilateral cortex at 1 and 2 weeks and in the ipsilateral striatum at 6 h after CCI compared with sham animals. Immunohistochemical analysis revealed lower α-synuclein and a modest reduction in synaptophysin staining in the ipsilateral hippocampus at 1 week after CCI compared with sham animals, with no evidence of intracellular or extracellular α-synuclein aggregates. Collectively, these findings demonstrate that monomeric α-synuclein protein abundance in the hippocampus is reduced over an extensive (acute-to-chronic) post-injury interval. This deficit may contribute to the chronically impaired neurotransmission known to occur after TBI.
Collapse
Affiliation(s)
- S W Carlson
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - H Q Yan
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - Y Li
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - J Henchir
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - X Ma
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - M S Young
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - M D Ikonomovic
- Neurology, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA, 15261, USA
- VA Pittsburgh Healthcare System, Pittsburgh, PA, USA
| | - C E Dixon
- Neurological Surgery, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA.
- VA Pittsburgh Healthcare System, Pittsburgh, PA, USA.
| |
Collapse
|
257
|
Wu AG, Zhou XG, Qiao G, Yu L, Tang Y, Yan L, Qiu WQ, Pan R, Yu CL, Law BYK, Qin DL, Wu JM. Targeting microglial autophagic degradation in NLRP3 inflammasome-mediated neurodegenerative diseases. Ageing Res Rev 2021; 65:101202. [PMID: 33161129 DOI: 10.1016/j.arr.2020.101202] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 02/07/2023]
Abstract
Neuroinflammation is considered as a detrimental factor in neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), etc. Nucleotide-binding oligomerization domain-, leucine-rich repeat- and pyrin domain-containing 3 (NLRP3), the most well-studied inflammasome, is abundantly expressed in microglia and has gained considerable attention. Misfolded proteins are characterized as the common hallmarks of neurodegenerative diseases due to not only their induced neuronal toxicity but also their effects in over-activating microglia and the NLRP3 inflammasome. The activated NLRP3 inflammasome aggravates the pathology and accelerates the progression of neurodegenerative diseases. Emerging evidence indicates that microglial autophagy plays an important role in the maintenance of brain homeostasis and the negative regulation of NLRP3 inflammasome-mediated neuroinflammation. The excessive activation of NLRP3 inflammasome impairs microglial autophagy and further aggravates the pathogenesis of neurodegenerative diseases. In this review article, we summarize and discuss the NLRP3 inflammasome and its specific inhibitors in microglia. The crucial role of microglial autophagy and its inducers in the removal of misfolded proteins, the clearance of damaged mitochondria and reactive oxygen species (ROS), and the degradation of the NLRP3 inflammasome or its components in neurodegenerative diseases are summarized. Understanding the underlying mechanisms behind the sex differences in NLRP3 inflammasome-mediated neurodegenerative diseases will help researchers to develop more targeted therapies and increase our diagnostic and prognostic abilities. In addition, the superiority of the combined use of microglial autophagy inducers with the specific inhibitors of the NLRP3 inflammasome in the inhibition of NLRP3 inflammasome-mediated neuroinflammation requires further preclinical and clinical validations in the future.
Collapse
|
258
|
Qin Y, Qiu J, Wang P, Liu J, Zhao Y, Jiang F, Lou H. Impaired autophagy in microglia aggravates dopaminergic neurodegeneration by regulating NLRP3 inflammasome activation in experimental models of Parkinson's disease. Brain Behav Immun 2021; 91:324-338. [PMID: 33039664 DOI: 10.1016/j.bbi.2020.10.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 09/25/2020] [Accepted: 10/06/2020] [Indexed: 11/16/2022] Open
Abstract
Microglia-mediated inflammation plays an important role in the pathogenesis of several neurodegenerative diseases including Parkinson's disease (PD). Recently, autophagy has been linked to the regulation of the inflammatory response. However, the potential role of microglial autophagy in the context of PD pathology has not been characterized. In the present study, we investigated whether impaired microglial autophagy would affect dopaminergic neurodegeneration and neuroinflammation both in vivo and in vitro. In vitro, BV2 microglial cells were exposed to LPS in the presence or absence of autophagy-related gene 5 (Atg5) small interference RNA (Atg5-siRNA). For in vivo study, microglial Atg5 conditional knockout (Atg5flox/flox; CX3CR1-Cre) mice and their wild-type littermates (Atg5flox/flox) were intraperitoneally injected with MPTP to induce experimental PD model. Our results revealed that disruption of autophagy by Atg5-siRNA aggravated LPS-induced inflammatory responses in BV2 cells and caused greater apoptosis in SH-SY5Y cells treated with BV2 conditioned medium. In mice, impaired autophagy in microglia exacerbated dopaminergic neuron loss in response to MPTP. The mechanism by which the deficiency of microglial autophagy promoted neuroinflammation and dopaminergic neurodegeneration was related to the regulation of NLRP3 inflammasome activation. These findings demonstrate that impairing microglial autophagy aggravates pro-inflammatory responses to LPS and exacerbates MPTP-induced neurodegeneration by modulating NLRP3 inflammasome responses. We anticipate that enhancing microglial autophagy may be a promising new therapeutic strategy for PD.
Collapse
Affiliation(s)
- Yue Qin
- Department of Pharmacology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Jingru Qiu
- Department of Pharmacology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Ping Wang
- Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 250021, China
| | - Jia Liu
- Department of Pharmacology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Yong Zhao
- Department of Pharmacology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Fan Jiang
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Haiyan Lou
- Department of Pharmacology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China.
| |
Collapse
|
259
|
Choi YR, Park SJ, Park SM. Molecular events underlying the cell-to-cell transmission of α-synuclein. FEBS J 2020; 288:6593-6602. [PMID: 33332736 DOI: 10.1111/febs.15674] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 12/26/2022]
Abstract
The pathogenesis of Parkinson's disease (PD), which is a progressive neurodegenerative disease, is associated with the formation of protein inclusion bodies called Lewy bodies (LB) or Lewy neurites (LN). α-Synuclein (α-Syn) is a major component of LB and LN. The formation of LB or LN is mediated by formation of α-Syn fibrils, which are formed from α-Syn monomers and oligomers. Additionally, intercellular α-Syn propagation has been proposed to be important for the progression of PD. Thus, various studies have focused on elucidating the role of α-Syn propagation in the pathogenesis of PD. Previous studies have reported that α-Syn species are released from the cells through various pathways, including the unconventional secretion pathways. The released α-Syn species are internalized by the cells through multiple mechanisms, including receptor-mediated endocytosis. Some molecular processes involved in intercellular α-Syn propagation have been recently elucidated. This review discusses the current studies on the molecular mechanisms underlying the release and uptake of α-Syn and their physiological relevance.
Collapse
Affiliation(s)
- Yu Ree Choi
- Department of Pharmacology, Ajou University School of Medicine, Suwon, Korea.,Center for Convergence Research of Neurological Disorders, Ajou University School of Medicine, Suwon, Korea.,BK21 Plus Program, Department of Biomedical Sciences, Ajou University School of Medicine, Suwon, Korea
| | - Soo Jin Park
- Department of Pharmacology, Ajou University School of Medicine, Suwon, Korea.,Center for Convergence Research of Neurological Disorders, Ajou University School of Medicine, Suwon, Korea.,Department of Thoracic and Cardiovascular Surgery, Ajou University School of Medicine, Suwon, Korea
| | - Sang Myun Park
- Department of Pharmacology, Ajou University School of Medicine, Suwon, Korea.,Center for Convergence Research of Neurological Disorders, Ajou University School of Medicine, Suwon, Korea.,BK21 Plus Program, Department of Biomedical Sciences, Ajou University School of Medicine, Suwon, Korea
| |
Collapse
|
260
|
Miyazaki I, Asanuma M. Neuron-Astrocyte Interactions in Parkinson's Disease. Cells 2020; 9:cells9122623. [PMID: 33297340 PMCID: PMC7762285 DOI: 10.3390/cells9122623] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/20/2020] [Accepted: 12/05/2020] [Indexed: 12/12/2022] Open
Abstract
Parkinson’s disease (PD) is the second most common neurodegenerative disease. PD patients exhibit motor symptoms such as akinesia/bradykinesia, tremor, rigidity, and postural instability due to a loss of nigrostriatal dopaminergic neurons. Although the pathogenesis in sporadic PD remains unknown, there is a consensus on the involvement of non-neuronal cells in the progression of PD pathology. Astrocytes are the most numerous glial cells in the central nervous system. Normally, astrocytes protect neurons by releasing neurotrophic factors, producing antioxidants, and disposing of neuronal waste products. However, in pathological situations, astrocytes are known to produce inflammatory cytokines. In addition, various studies have reported that astrocyte dysfunction also leads to neurodegeneration in PD. In this article, we summarize the interaction of astrocytes and dopaminergic neurons, review the pathogenic role of astrocytes in PD, and discuss therapeutic strategies for the prevention of dopaminergic neurodegeneration. This review highlights neuron-astrocyte interaction as a target for the development of disease-modifying drugs for PD in the future.
Collapse
|
261
|
Cserép C, Pósfai B, Dénes Á. Shaping Neuronal Fate: Functional Heterogeneity of Direct Microglia-Neuron Interactions. Neuron 2020; 109:222-240. [PMID: 33271068 DOI: 10.1016/j.neuron.2020.11.007] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/13/2020] [Accepted: 11/06/2020] [Indexed: 12/11/2022]
Abstract
The functional contribution of microglia to normal brain development, healthy brain function, and neurological disorders is increasingly recognized. However, until recently, the nature of intercellular interactions mediating these effects remained largely unclear. Recent findings show microglia establishing direct contact with different compartments of neurons. Although communication between microglia and neurons involves intermediate cells and soluble factors, direct membrane contacts enable a more precisely regulated, dynamic, and highly effective form of interaction for fine-tuning neuronal responses and fate. Here, we summarize the known ultrastructural, molecular, and functional features of direct microglia-neuron interactions and their roles in brain disease.
Collapse
Affiliation(s)
- Csaba Cserép
- "Momentum" Laboratory of Neuroimmunology, Institute of Experimental Medicine, Szigony u. 43, 1083 Budapest, Hungary
| | - Balázs Pósfai
- "Momentum" Laboratory of Neuroimmunology, Institute of Experimental Medicine, Szigony u. 43, 1083 Budapest, Hungary; Szentágothai János Doctoral School of Neurosciences, Semmelweis University, Üllői út 26, 1085 Budapest, Hungary
| | - Ádám Dénes
- "Momentum" Laboratory of Neuroimmunology, Institute of Experimental Medicine, Szigony u. 43, 1083 Budapest, Hungary.
| |
Collapse
|
262
|
Autophagy Pathways in CNS Myeloid Cell Immune Functions. Trends Neurosci 2020; 43:1024-1033. [DOI: 10.1016/j.tins.2020.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/17/2020] [Accepted: 09/04/2020] [Indexed: 02/06/2023]
|
263
|
Le Guerroué F, Youle RJ. Ubiquitin signaling in neurodegenerative diseases: an autophagy and proteasome perspective. Cell Death Differ 2020; 28:439-454. [PMID: 33208890 DOI: 10.1038/s41418-020-00667-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 10/28/2020] [Accepted: 10/30/2020] [Indexed: 12/13/2022] Open
Abstract
Ubiquitin signaling is a sequence of events driving the fate of a protein based on the type of ubiquitin modifications attached. In the case of neurodegenerative diseases, ubiquitin signaling is mainly associated with degradation signals to process aberrant proteins, which form aggregates often fatal for the brain cells. This signaling is often perturbed by the aggregates themselves and leads to the accumulation of toxic aggregates and inclusion bodies that are deleterious due to a toxic gain of function. Decrease in quality control pathways is often seen with age and is a critical onset for the development of neurodegeneration. Many aggregates are now thought to propagate in a prion-like manner, where mutated proteins acting like seeds are transitioning from cell to cell, converting normal proteins to toxic aggregates. Modulation of ubiquitin signaling, by stimulating ubiquitin ligase activation, is a potential therapeutic strategy to treat patients with neurodegeneration diseases.
Collapse
Affiliation(s)
- François Le Guerroué
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard J Youle
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
| |
Collapse
|
264
|
Jeon YM, Kwon Y, Jo M, Lee S, Kim S, Kim HJ. The Role of Glial Mitochondria in α-Synuclein Toxicity. Front Cell Dev Biol 2020; 8:548283. [PMID: 33262983 PMCID: PMC7686475 DOI: 10.3389/fcell.2020.548283] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 10/20/2020] [Indexed: 12/18/2022] Open
Abstract
The abnormal accumulation of alpha-synuclein (α-syn) aggregates in neurons and glial cells is widely known to be associated with many neurodegenerative diseases, including Parkinson's disease (PD), Dementia with Lewy bodies (DLB), and Multiple system atrophy (MSA). Mitochondrial dysfunction in neurons and glia is known as a key feature of α-syn toxicity. Studies aimed at understanding α-syn-induced toxicity and its role in neurodegenerative diseases have primarily focused on neurons. However, a growing body of evidence demonstrates that glial cells such as microglia and astrocytes have been implicated in the initial pathogenesis and the progression of α-Synucleinopathy. Glial cells are important for supporting neuronal survival, synaptic functions, and local immunity. Furthermore, recent studies highlight the role of mitochondrial metabolism in the normal function of glial cells. In this work, we review the complex relationship between glial mitochondria and α-syn-mediated neurodegeneration, which may provide novel insights into the roles of glial cells in α-syn-associated neurodegenerative diseases.
Collapse
Affiliation(s)
- Yu-Mi Jeon
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Younghwi Kwon
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
- Department of Brain and Cognitive Sciences, DGIST, Daegu, South Korea
| | - Myungjin Jo
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Shinrye Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Seyeon Kim
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
- Department of Brain and Cognitive Sciences, DGIST, Daegu, South Korea
| | - Hyung-Jun Kim
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| |
Collapse
|
265
|
Marogianni C, Sokratous M, Dardiotis E, Hadjigeorgiou GM, Bogdanos D, Xiromerisiou G. Neurodegeneration and Inflammation-An Interesting Interplay in Parkinson's Disease. Int J Mol Sci 2020; 21:E8421. [PMID: 33182554 PMCID: PMC7697354 DOI: 10.3390/ijms21228421] [Citation(s) in RCA: 164] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 10/30/2020] [Accepted: 11/06/2020] [Indexed: 12/12/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder, caused by, so far, unknown pathogenetic mechanisms. There is no doubt that pro-inflammatory immune-mediated mechanisms are pivotal to the pathogenicity and progression of the disease. In this review, we highlight the binary role of microglia activation in the pathophysiology of the disorder, both neuroprotective and neuromodulatory. We present how the expression of several cytokines implicated in dopaminergic neurons (DA) degeneration could be used as biomarkers for PD. Viral infections have been studied and correlated to the disease progression, usually operating as trigger factors for the inflammatory process. The gut-brain axis and the possible contribution of the peripheral bowel inflammation to neuronal death, mainly dopaminergic neurons, seems to be a main contributor of brain neuroinflammation. The role of the immune system has also been analyzed implicating a-synuclein in the activation of innate and adaptive immunity. We also discuss therapeutic approaches concerning PD and neuroinflammation, which have been studied in experimental and in vitro models and data stemming from epidemiological studies.
Collapse
Affiliation(s)
- Chrysoula Marogianni
- Department of Neurology, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.M.); (M.S.); (E.D.)
| | - Maria Sokratous
- Department of Neurology, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.M.); (M.S.); (E.D.)
| | - Efthimios Dardiotis
- Department of Neurology, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.M.); (M.S.); (E.D.)
| | | | - Dimitrios Bogdanos
- Department of Internal Medicine, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece;
| | - Georgia Xiromerisiou
- Department of Neurology, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.M.); (M.S.); (E.D.)
| |
Collapse
|
266
|
Lecours C, St-Pierre MK, Picard K, Bordeleau M, Bourque M, Awogbindin IO, Benadjal A, Ibanez FG, Gagnon D, Cantin L, Parent M, Di Paolo T, Tremblay ME. Levodopa partially rescues microglial numerical, morphological, and phagolysosomal alterations in a monkey model of Parkinson's disease. Brain Behav Immun 2020; 90:81-96. [PMID: 32755645 DOI: 10.1016/j.bbi.2020.07.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/23/2020] [Accepted: 07/29/2020] [Indexed: 02/07/2023] Open
Abstract
Parkinson's disease (PD) is the most common neurodegenerative motor disorder. The mechanisms underlying the onset and progression of Levodopa (L-Dopa)-induced dyskinesia (LID) during PD treatment remain elusive. Emerging evidence implicates functional modification of microglia in the development of LID. Thus, understanding the link between microglia and the development of LID may provide the knowledge required to preserve or promote beneficial microglial functions, even during a prolonged L-Dopa treatment. To provide novel insights into microglial functional alterations in PD pathophysiology, we characterized their density, morphology, ultrastructure, and degradation activity in the sensorimotor functional territory of the putamen, using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) cynomolgus monkeys. A subset of MPTP monkeys was treated orally with L-Dopa and developed LID similar to PD patients. Using a combination of light, confocal and transmission electron microscopy, our quantitative analyses revealed alterations of microglial density, morphology and phagolysosomal activity following MPTP intoxication that were partially normalized with L-Dopa treatment. In particular, microglial density, cell body and arborization areas were increased in the MPTP monkeys, whereas L-Dopa-treated MPTP animals presented a microglial phenotype similar to the control animals. At the ultrastructural level, microglia did not differ between groups in their markers of cellular stress or aging. Nevertheless, microglia from the MPTP monkeys displayed reduced numbers of endosomes, compared with control animals, that remained lower after L-Dopa treatment. Microglia from MPTP monkeys treated with L-Dopa also had increased numbers of primary lysosomes compared with non-treated MPTP animals, while secondary and tertiary lysosomes remained unchanged. Moreover, a decrease microglial immunoreactivity for CD68, considered a marker of phagocytosis and lysosomal activity, was measured in the MPTP monkeys treated with L-Dopa, compared with non-treated MPTP animals. Taken together, these findings revealed significant changes in microglia during PD pathophysiology that were partially rescued by L-Dopa treatment. Albeit, this L-Dopa treatment conferred phagolysosomal insufficiency on microglia in the dyskinetic Parkinsonian monkeys.
Collapse
Affiliation(s)
- Cynthia Lecours
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Faculté de Pharmacie, Université Laval, Québec, QC, Canada
| | - Marie-Kim St-Pierre
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
| | - Katherine Picard
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
| | - Maude Bordeleau
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Integrated Program of Neuroscience, Faculty of Medicine, McGill University, Montréal, QC, Canada
| | - Melanie Bourque
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
| | - Ifeoluwa Oluleke Awogbindin
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Neuroimmunology Group, Molecular Drug Metabolism and Toxicology Laboratory, Department of Biochemistry, University of Ibadan, Ibadan, Nigeria
| | - Amin Benadjal
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Biologie Intégrative et Physiologie, Sorbonne Université, Paris VI, France
| | | | - Dave Gagnon
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Québec, QC, Canada; CERVO Brain Research Center, Québec, QC, Canada
| | - Leo Cantin
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Département de Chirurgie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Martin Parent
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Québec, QC, Canada; CERVO Brain Research Center, Québec, QC, Canada
| | - Therese Di Paolo
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Faculté de Pharmacie, Université Laval, Québec, QC, Canada.
| | - Marie-Eve Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Département de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec, QC, Canada; Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
267
|
Ejma M, Madetko N, Brzecka A, Guranski K, Alster P, Misiuk-Hojło M, Somasundaram SG, Kirkland CE, Aliev G. The Links between Parkinson's Disease and Cancer. Biomedicines 2020; 8:biomedicines8100416. [PMID: 33066407 PMCID: PMC7602272 DOI: 10.3390/biomedicines8100416] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/08/2020] [Accepted: 10/12/2020] [Indexed: 12/12/2022] Open
Abstract
Epidemiologic studies indicate a decreased incidence of most cancer types in Parkinson’s disease (PD) patients. However, some neoplasms are associated with a higher risk of occurrence in PD patients. Both pathologies share some common biological pathways. Although the etiologies of PD and cancer are multifactorial, some factors associated with PD, such as α-synuclein aggregation; mutations of PINK1, PARKIN, and DJ-1; mitochondrial dysfunction; and oxidative stress can also be involved in cancer proliferation or cancer suppression. The main protein associated with PD, i.e., α-synuclein, can be involved in some types of neoplastic formations. On the other hand, however, its downregulation has been found in the other cancers. PINK1 can act as oncogenic or a tumor suppressor. PARKIN dysfunction may lead to some cancers’ growth, and its expression may be associated with some tumors’ suppression. DJ-1 mutation is involved in PD pathogenesis, but its increased expression was found in some neoplasms, such as melanoma or breast, lung, colorectal, uterine, hepatocellular, and nasopharyngeal cancers. Both mitochondrial dysfunction and oxidative stress are involved in PD and cancer development. The aim of this review is to summarize the possible associations between PD and carcinogenesis.
Collapse
Affiliation(s)
- Maria Ejma
- Department of Neurology, Wroclaw Medical University, Borowska 213, 50-556 Wrocław, Poland; (M.E.); (N.M.); (K.G.)
| | - Natalia Madetko
- Department of Neurology, Wroclaw Medical University, Borowska 213, 50-556 Wrocław, Poland; (M.E.); (N.M.); (K.G.)
| | - Anna Brzecka
- Department of Pulmonology and Lung Oncology, Wroclaw Medical University, Grabiszyńska 105, 53-439 Wroclaw, Poland;
| | - Konstanty Guranski
- Department of Neurology, Wroclaw Medical University, Borowska 213, 50-556 Wrocław, Poland; (M.E.); (N.M.); (K.G.)
| | - Piotr Alster
- Department of Neurology, Medical University of Warsaw, Kondratowicza 8, 03-242 Warszawa, Poland;
| | - Marta Misiuk-Hojło
- Department of Ophthalmology, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland;
| | - Siva G. Somasundaram
- Department of Biological Sciences, Salem University, Salem, WV 26426, USA; (S.G.S.); (C.E.K.)
| | - Cecil E. Kirkland
- Department of Biological Sciences, Salem University, Salem, WV 26426, USA; (S.G.S.); (C.E.K.)
| | - Gjumrakch Aliev
- Sechenov First Moscow State Medical University (Sechenov University), St. Trubetskaya, 8, bld. 2, 119991 Moscow, Russia
- Research Institute of Human Morphology, Russian Academy of Medical Science, Street Tsyurupa 3, 117418 Moscow, Russia
- Institute of Physiologically Active Compounds, Russian Academy of Sciences, Chernogolovka, 142432 Moscow Region, Russia
- GALLY International Research Institute, 7733 Louis Pasteur Drive, #330, San Antonio, TX 78229, USA
- Correspondence: or ; Tel.: +1-210-442-8625 or +1-440-263-7461
| |
Collapse
|
268
|
Bartels T, De Schepper S, Hong S. Microglia modulate neurodegeneration in Alzheimer's and Parkinson's diseases. Science 2020; 370:66-69. [PMID: 33004513 DOI: 10.1126/science.abb8587] [Citation(s) in RCA: 212] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dementia is a rapidly rising global health crisis that silently disables families and ends lives and livelihoods around the world. To date, however, no early biomarkers or effective therapies exist. It is now clear that brain microglia are more than mere bystanders or amyloid phagocytes; they can act as governors of neuronal function and homeostasis in the adult brain. Here, we highlight the fundamental role of microglia as tissue-resident macrophages in neuronal health. Then, we suggest how chronic impairment in microglia-neuron cross-talk may secure the permanence of the failure of synaptic and neuronal function and health in Alzheimer's and Parkinson's diseases. Understanding how to assess and modulate microglia-neuron interactions critical for brain health will be key to developing effective therapies for dementia.
Collapse
Affiliation(s)
- Tim Bartels
- UK Dementia Research Institute, Institute of Neurology, University College London, London WC1E 6BT, UK
| | - Sebastiaan De Schepper
- UK Dementia Research Institute, Institute of Neurology, University College London, London WC1E 6BT, UK
| | - Soyon Hong
- UK Dementia Research Institute, Institute of Neurology, University College London, London WC1E 6BT, UK.
| |
Collapse
|
269
|
Heras-Garvin A, Stefanova N. From Synaptic Protein to Prion: The Long and Controversial Journey of α-Synuclein. Front Synaptic Neurosci 2020; 12:584536. [PMID: 33071772 PMCID: PMC7536368 DOI: 10.3389/fnsyn.2020.584536] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Since its discovery 30 years ago, α-synuclein (α-syn) has been one of the most studied proteins in the field of neuroscience. Dozens of groups worldwide have tried to reveal not only its role in the CNS but also in other organs. α-syn has been linked to several processes essential in brain homeostasis such as neurotransmitter release, synaptic function, and plasticity. However, despite the efforts made in this direction, the main function of α-syn is still unknown. Moreover, α-syn became a protein of interest for neurologists and neuroscientists when mutations in its gene were found associated with Parkinson's disease (PD) and even more when α-syn protein deposits were observed in the brain of PD, dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) patients. At present, the abnormal accumulation of α-syn constitutes one of the pathological hallmarks of these disorders, also referred to as α-synucleinopathies, and it is used for post-mortem diagnostic criteria. Whether α-syn aggregation is cause or consequence of the pathogenic events underlying α-synucleinopathies remains unclear and under discussion. Recently, different in vitro and in vivo studies have shown the ability of pathogenic α-syn to spread between cells, not only within the CNS but also from peripheral locations such as the gut, salivary glands, and through the olfactory network into the CNS, inducing abnormal misfolding of endogenous α-syn and leading to neurodegeneration and motor and cognitive impairment in animal models. Thus, it has been suggested that α-syn should be considered a prion protein. Here we present an update of what we know about α-syn function, aggregation and spreading, and its role in neurodegeneration. We also discuss the rationale and findings supporting the hypothetical prion nature of α-syn, its weaknesses, and future perspectives for research and the development of disease-modifying therapies.
Collapse
Affiliation(s)
- Antonio Heras-Garvin
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Nadia Stefanova
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
270
|
Fatoba O, Itokazu T, Yamashita T. Microglia as therapeutic target in central nervous system disorders. J Pharmacol Sci 2020; 144:102-118. [PMID: 32921391 DOI: 10.1016/j.jphs.2020.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/19/2020] [Accepted: 07/07/2020] [Indexed: 12/17/2022] Open
Abstract
Chronic microglial activation is associated with the pathogenesis of several CNS disorders. Microglia show phenotypic diversity and functional complexity in diseased CNS. Thus, understanding the pathology-specific heterogeneity of microglial behavior is crucial for the future development of microglia-modulating therapy for variety of CNS disorders. This review summarizes up-to-date knowledge on how microglia contribute to CNS homeostasis during development and throughout adulthood. We discuss the heterogeneity of microglial phenotypes in the context of CNS disorders with an emphasis on neurodegenerative diseases, demyelinating diseases, CNS trauma, and epilepsy. We conclude this review with a discussion about the disease-specific heterogeneity of microglial function and how it could be exploited for therapeutic intervention.
Collapse
Affiliation(s)
- Oluwaseun Fatoba
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; WPI-Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Takahide Itokazu
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Neuro-Medical Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Toshihide Yamashita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; WPI-Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Neuro-Medical Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
271
|
Ripon MKH, Lee H, Dash R, Choi HJ, Oktaviani DF, Moon IS, Haque MN. N-acetyl-D-glucosamine kinase binds dynein light chain roadblock 1 and promotes protein aggregate clearance. Cell Death Dis 2020; 11:619. [PMID: 32796833 PMCID: PMC7427805 DOI: 10.1038/s41419-020-02862-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/30/2020] [Accepted: 07/03/2020] [Indexed: 12/18/2022]
Abstract
Emerging evidence indicates that neurodegenerative diseases (NDs) result from a failure to clear toxic protein aggregates rather than from their generation. We previously showed N-acetylglucosamine kinase (NAGK) promotes dynein functionality and suggested this might promote aggregate removal and effectively address proteinopathies. Here, we report NAGK interacts with dynein light chain roadblock type 1 (DYNLRB1) and efficiently suppresses mutant huntingtin (mHtt) (Q74) and α-synuclein (α-syn) A53T aggregation in mouse brain cells. A kinase-inactive NAGKD107A also efficiently cleared Q74 aggregates. Yeast two-hybrid selection and in silico protein-protein docking analysis showed the small domain of NAGK (NAGK-DS) binds to the C-terminal of DYNLRB1. Furthermore, a small peptide derived from NAGK-DS interfered with Q74 clearance. We propose binding of NAGK-DS to DYNLRB1 'pushes up' the tail of dynein light chain and confers momentum for inactive phi- to active open-dynein transition.
Collapse
Affiliation(s)
- Md Kamal Hossain Ripon
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
- Department of Pharmacy, Mawlana Bhashani Science and Technology University, Tangail, 1902, Bangladesh
| | - HyunSook Lee
- Section of Neuroscience, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Raju Dash
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Ho Jin Choi
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Diyah Fatimah Oktaviani
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Il Soo Moon
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea.
- Section of Neuroscience, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea.
| | - Md Nazmul Haque
- Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
- Department of Fisheries Biology and Genetics, Patuakhali Science and Technology University, Patuakhali, 8602, Bangladesh
| |
Collapse
|
272
|
Tanriöver G, Bacioglu M, Schweighauser M, Mahler J, Wegenast-Braun BM, Skodras A, Obermüller U, Barth M, Kronenberg-Versteeg D, Nilsson KPR, Shimshek DR, Kahle PJ, Eisele YS, Jucker M. Prominent microglial inclusions in transgenic mouse models of α-synucleinopathy that are distinct from neuronal lesions. Acta Neuropathol Commun 2020; 8:133. [PMID: 32787922 PMCID: PMC7425556 DOI: 10.1186/s40478-020-00993-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/09/2020] [Indexed: 11/29/2023] Open
Abstract
Alpha-synucleinopathies are a group of progressive neurodegenerative disorders, characterized by intracellular deposits of aggregated α-synuclein (αS). The clinical heterogeneity of these diseases is thought to be attributed to conformers (or strains) of αS but the contribution of inclusions in various cell types is unclear. The aim of the present work was to study αS conformers among different transgenic (TG) mouse models of α-synucleinopathies. To this end, four different TG mouse models were studied (Prnp-h[A53T]αS; Thy1-h[A53T]αS; Thy1-h[A30P]αS; Thy1-mαS) that overexpress human or murine αS and differed in their age-of-symptom onset and subsequent disease progression. Postmortem analysis of end-stage brains revealed robust neuronal αS pathology as evidenced by accumulation of αS serine 129 (p-αS) phosphorylation in the brainstem of all four TG mouse lines. Overall appearance of the pathology was similar and only modest differences were observed among additionally affected brain regions. To study αS conformers in these mice, we used pentameric formyl thiophene acetic acid (pFTAA), a fluorescent dye with amyloid conformation-dependent spectral properties. Unexpectedly, besides the neuronal αS pathology, we also found abundant pFTAA-positive inclusions in microglia of all four TG mouse lines. These microglial inclusions were also positive for Thioflavin S and showed immunoreactivity with antibodies recognizing the N-terminus of αS, but were largely p-αS-negative. In all four lines, spectral pFTAA analysis revealed conformational differences between microglia and neuronal inclusions but not among the different mouse models. Concomitant with neuronal lesions, microglial inclusions were already present at presymptomatic stages and could also be induced by seeded αS aggregation. Although nature and significance of microglial inclusions for human α-synucleinopathies remain to be clarified, the previously overlooked abundance of microglial inclusions in TG mouse models of α-synucleinopathy bears importance for mechanistic and preclinical-translational studies.
Collapse
|
273
|
Zheng H, Shi C, Luo H, Fan L, Yang Z, Hu X, Zhang Z, Zhang S, Hu Z, Fan Y, Yang J, Mao C, Xu Y. α-Synuclein in Parkinson's Disease: Does a Prion-Like Mechanism of Propagation from Periphery to the Brain Play a Role? Neuroscientist 2020; 27:367-387. [PMID: 32729773 DOI: 10.1177/1073858420943180] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative diseases, defined as motor and non-motor symptoms associated with the loss of dopaminergic neurons and a decreased release of dopamine (DA). Currently, PD patients are believed to have a neuropathological basis denoted by the presence of Lewy bodies (LBs) or Lewy neurites (LNs), which mostly comprise α-synuclein (α-syn) inclusions. Remarkably, there is a growing body of evidence indicating that the inclusions undergo template-directed aggregation and propagation via template-directed among the brain and peripheral organs, mainly in a prion-like manner. Interestingly, some studies reported that an integral loop was reminiscent of the mechanism of Parkinson's disease, denoting that α-syn as prionoid was transmitted from the periphery to the brain via specific pathways. Also the systematic life cycle of α-syn in the cellular level is illustrated. In this review, we critically assess landmark evidence in the field of Parkinson's disease with a focus on the genesis and prion-like propagation of the α-syn pathology. The anatomical and cell-to-cell evidences are discussed to depict the theory behind the propagation and transferred pathways. Furthermore, we highlight effective therapeutic perspectives and clinical trials targeting prion-like mechanisms. Major controversies surrounding this topic are also discussed.
Collapse
Affiliation(s)
- Huimin Zheng
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Changhe Shi
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
| | - Haiyang Luo
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Liyuan Fan
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory for Pharmacology of Liver Diseases, Zhengzhou University, Zhengzhou, Henan, China
| | - Zhihua Yang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Xinchao Hu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Zhongxian Zhang
- The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Sino-British Research Centre for Molecular Oncology, National Centre for International Research in Cell and Gene Therapy, School of Basic Medical Sciences, Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Shuo Zhang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Zhengwei Hu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Yu Fan
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Jing Yang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
| | - Chengyuan Mao
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,The Academy of Medical Sciences of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Sino-British Research Centre for Molecular Oncology, National Centre for International Research in Cell and Gene Therapy, School of Basic Medical Sciences, Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Yuming Xu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
| |
Collapse
|
274
|
Rodríguez-Gómez JA, Kavanagh E, Engskog-Vlachos P, Engskog MK, Herrera AJ, Espinosa-Oliva AM, Joseph B, Hajji N, Venero JL, Burguillos MA. Microglia: Agents of the CNS Pro-Inflammatory Response. Cells 2020; 9:E1717. [PMID: 32709045 PMCID: PMC7407646 DOI: 10.3390/cells9071717] [Citation(s) in RCA: 168] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/14/2020] [Accepted: 07/15/2020] [Indexed: 12/21/2022] Open
Abstract
The pro-inflammatory immune response driven by microglia is a key contributor to the pathogenesis of several neurodegenerative diseases. Though the research of microglia spans over a century, the last two decades have increased our understanding exponentially. Here, we discuss the phenotypic transformation from homeostatic microglia towards reactive microglia, initiated by specific ligand binding to pattern recognition receptors including toll-like receptor-4 (TLR4) or triggering receptors expressed on myeloid cells-2 (TREM2), as well as pro-inflammatory signaling pathways triggered such as the caspase-mediated immune response. Additionally, new research disciplines such as epigenetics and immunometabolism have provided us with a more holistic view of how changes in DNA methylation, microRNAs, and the metabolome may influence the pro-inflammatory response. This review aimed to discuss our current knowledge of pro-inflammatory microglia from different angles, including recent research highlights such as the role of exosomes in spreading neuroinflammation and emerging techniques in microglia research including positron emission tomography (PET) scanning and the use of human microglia generated from induced pluripotent stem cells (iPSCs). Finally, we also discuss current thoughts on the impact of pro-inflammatory microglia in neurodegenerative diseases.
Collapse
Affiliation(s)
- José A. Rodríguez-Gómez
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Medical Physiology and Biophysics, Faculty of Medicine, University of Seville, 41009 Sevilla, Spain
| | - Edel Kavanagh
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Pinelopi Engskog-Vlachos
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institute, 17177 Stockholm, Sweden; (P.E.-V.); (B.J.)
| | - Mikael K.R. Engskog
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, 751 23 Uppsala, Sweden;
| | - Antonio J. Herrera
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Ana M. Espinosa-Oliva
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Bertrand Joseph
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institute, 17177 Stockholm, Sweden; (P.E.-V.); (B.J.)
| | - Nabil Hajji
- Division of Brain Sciences, The John Fulcher Molecular Neuro-Oncology Laboratory, Imperial College London, London W12 ONN, UK;
| | - José L. Venero
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Miguel A. Burguillos
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| |
Collapse
|
275
|
Choi I, Seegobin SP, Liang D, Yue Z. Synucleinphagy: a microglial "community cleanup program" for neuroprotection. Autophagy 2020; 16:1718-1720. [PMID: 32453651 DOI: 10.1080/15548627.2020.1774149] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
SNCA/α-synuclein is a major component in the Lewy body (LB), a pathological hallmark of Parkinson disease (PD) and dementia with Lewy body (DLB), collectively known as synucleinopathies. SNCA/α-synuclein can be secreted from neurons and transmitted to neighboring cells including neurons and glia, which underlie the spreading of LB pathology as described by Braak and colleagues. We recently have investigated the mechanism and significance for microglia, a prototypic phagocyte in the brain, in engulfing and controlling SNCA/α-synuclein homeostasis in the brain. Using microglia-specific autophagy-deficient mice, we demonstrated that microglia ingest and degrade neuron-released SNCA/α-synuclein through SQSTM1/p62-mediated selective autophagy both in vivo and in vitro. This process requires the presence of TLR4 (toll like receptor 4), which interacts with SNCA/α-synuclein to induce the transcriptional upregulation of Sqstm1/p62 through the NFKB/NF-κB pathway. We term the selective autophagy of SNCA/α-synuclein as "synucleinphagy". We showed that the disruption of microglial autophagy causes accumulation of misfolded SNCA/α-synuclein and loss of dopaminergic neurons, two hallmarks of PD. Hence, our study reveals a neuroprotective role of microglia through an autophagy-mediated "community cleanup program".
Collapse
Affiliation(s)
- Insup Choi
- Departments of Neurology and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY, USA
| | - Steven P Seegobin
- Departments of Neurology and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY, USA
| | - Dongxiao Liang
- Departments of Neurology and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY, USA.,Department of Neurology, Xiangya Hospital, Central South University , Changsha, Hunan, China
| | - Zhenyu Yue
- Departments of Neurology and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY, USA
| |
Collapse
|
276
|
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
|