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Wang YF, Wang YD, Gao S, Sun W. Implications of p53 in mitochondrial dysfunction and Parkinson's disease. Int J Neurosci 2024; 134:906-917. [PMID: 36514978 DOI: 10.1080/00207454.2022.2158824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022]
Abstract
Purpose: To study the underlying molecular mechanisms of p53 in the mitochondrial dysfunction and the pathogenesis of Parkinson's disease (PD), and provide a potential therapeutic target for PD treatment. Methods: We review the contributions of p53 to mitochondrial changes leading to apoptosis and the subsequent degeneration of dopaminergic neurons in PD. Results: P53 is a multifunctional protein implicated in the regulation of diverse cellular processes via transcription-dependent and transcription-independent mechanisms. Mitochondria are vital subcellular organelles for that maintain cellular function, and mitochondrial defect and impairment are primary causes of dopaminergic neuron degeneration in PD. Increasing evidence has revealed that mitochondrial dysfunction-associated dopaminergic neuron degeneration is tightly regulated by p53 in PD pathogenesis. Neurodegenerative stress triggers p53 activation, which induces mitochondrial changes, including transmembrane permeability, reactive oxygen species production, Ca2+ overload, electron transport chain defects and other dynamic alterations, and these changes contribute to neurodegeneration and are linked closely with PD occurrence and development. P53 inhibition has been shown to attenuate mitochondrial dysfunction and protect dopaminergic neurons from degeneration under conditions of neurodegenerative stress. Conclusions: p53 appears to be a potential target for neuroprotective therapy of PD.
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Affiliation(s)
- Yi-Fan Wang
- Department of Neurology, Shenzhen Sami Medical Center, Shenzhen, China
| | - Ying-Di Wang
- Department of Urinary Surgery, Tumor Hospital of Jilin Province, Chang Chun, China
| | - Song Gao
- Department of Anesthesiology, Tumor Hospital of Jilin Province, Chang Chun, China
| | - Wei Sun
- Department of Neurology, Shenzhen Sami Medical Center, Shenzhen, China
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2
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Yang Y, Shi M, Liu X, Zhu Q, Xu Z, Liu G, Feng T, Stewart T, Zhang J. Calcium influx: An essential process by which α-Synuclein regulates morphology of erythrocytes. J Adv Res 2024; 62:187-198. [PMID: 37714326 PMCID: PMC11331169 DOI: 10.1016/j.jare.2023.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/06/2023] [Accepted: 09/11/2023] [Indexed: 09/17/2023] Open
Abstract
INTRODUCTION Morphological abnormalities of erythrocytes/red blood cells (RBCs), e.g., increased acanthocytes, in Parkinson's disease (PD) have been reported previously, although the underlying mechanisms remain to be characterized. In this study, the potential roles of α-synuclein (α-syn), a protein critically involved in PD and highly abundant in RBCs, were studied in PD patients as well as in a PD mouse model. METHODS Transgenic [PAC-Tg (SNCAA53T), A53T] mice overexpressing A53T mutant α-syn and SNCA knockout mice were employed to characterize the effect of α-syn on RBC morphology. In addition to A53T and SNCA knockout mice, the morphology of RBCs of PD patients was also examined using scanning electron microscopy. The potential roles of α-syn were further investigated in cultured RBCs and mice. RESULTS Morphological abnormalities of RBCs and increased accumulation of aggregated α-syn on the RBC membrane were observed in PD patients. A similar phenomenon was also observed in A53T mice. Furthermore, while mice lacking α-syn expression showed a lower proportion of acanthocytes, treating RBCs derived from SNCA knockout mice with aggregated α-syn resulted in a higher percentage of acanthocytes. In a follow-up proteomic investigation, several major classes of proteins were identified as α-syn-associated proteins on the RBC membrane, seven of which were calcium-binding proteins. Applying aggregated α-syn to the RBC membrane directly induced extracellular calcium influx along with morphological changes; both observations were adequately reversed by blocking calcium influx. CONCLUSIONS This study demonstrated that α-syn plays a critical role in PD-associated morphological abnormalities of RBCs, at least partially via a process mediated by extracellular calcium influx.
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Affiliation(s)
- Ying Yang
- Department of Pathology, Zhejiang University First Affiliated Hospital and School of Medicine, Hangzhou, Zhejiang 310002, China; Department of Pathology, School of Basic Medical Sciences, Peking University Third Hospital, Peking University Health Science Center, Beijing 100191, China
| | - Min Shi
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - Xiaodan Liu
- Department of Pathology, School of Basic Medical Sciences, Peking University Third Hospital, Peking University Health Science Center, Beijing 100191, China
| | - Qiaoyun Zhu
- Central Laboratory, Zhejiang University First Affiliated Hospital and School of Medicine, Hangzhou, Zhejiang 310002, China
| | - Zhi Xu
- Department of Pathology, Zhejiang University First Affiliated Hospital and School of Medicine, Hangzhou, Zhejiang 310002, China
| | - Genliang Liu
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China; China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
| | - Tao Feng
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China; China National Clinical Research Center for Neurological Diseases, Beijing 100070, China.
| | - Tessandra Stewart
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98104, USA.
| | - Jing Zhang
- Department of Pathology, Zhejiang University First Affiliated Hospital and School of Medicine, Hangzhou, Zhejiang 310002, China; National Human Brain Bank for Health and Disease, Zhejiang University, Zhejiang, Hangzhou, China.
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3
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Currim F, Tanwar R, Brown-Leung JM, Paranjape N, Liu J, Sanders LH, Doorn JA, Cannon JR. Selective dopaminergic neurotoxicity modulated by inherent cell-type specific neurobiology. Neurotoxicology 2024; 103:266-287. [PMID: 38964509 PMCID: PMC11288778 DOI: 10.1016/j.neuro.2024.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 06/27/2024] [Accepted: 06/28/2024] [Indexed: 07/06/2024]
Abstract
Parkinson's disease (PD) is a debilitating neurodegenerative disease affecting millions of individuals worldwide. Hallmark features of PD pathology are the formation of Lewy bodies in neuromelanin-containing dopaminergic (DAergic) neurons of the substantia nigra pars compacta (SNpc), and the subsequent irreversible death of these neurons. Although genetic risk factors have been identified, around 90 % of PD cases are sporadic and likely caused by environmental exposures and gene-environment interaction. Mechanistic studies have identified a variety of chemical PD risk factors. PD neuropathology occurs throughout the brain and peripheral nervous system, but it is the loss of DAergic neurons in the SNpc that produce many of the cardinal motor symptoms. Toxicology studies have found specifically the DAergic neuron population of the SNpc exhibit heightened sensitivity to highly variable chemical insults (both in terms of chemical structure and mechanism of neurotoxic action). Thus, it has become clear that the inherent neurobiology of nigral DAergic neurons likely underlies much of this neurotoxic response to broad insults. This review focuses on inherent neurobiology of nigral DAergic neurons and how such neurobiology impacts the primary mechanism of neurotoxicity. While interactions with a variety of other cell types are important in disease pathogenesis, understanding how inherent DAergic biology contributes to selective sensitivity and primary mechanisms of neurotoxicity is critical to advancing the field. Specifically, key biological features of DAergic neurons that increase neurotoxicant susceptibility.
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Affiliation(s)
- Fatema Currim
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA
| | - Reeya Tanwar
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA
| | - Josephine M Brown-Leung
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA
| | - Neha Paranjape
- Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Jennifer Liu
- Departments of Neurology and Pathology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Center for Neurodegeneration and Neurotherapeutics, Duke University School of Medicine, Durham, NC 27710, USA
| | - Laurie H Sanders
- Departments of Neurology and Pathology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Center for Neurodegeneration and Neurotherapeutics, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jonathan A Doorn
- Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Jason R Cannon
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA.
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4
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Kim HS, Xiao Y, Chen X, He S, Im J, Willner MJ, Finlayson MO, Xu C, Zhu H, Choi SJ, Mosharov EV, Kim H, Xu B, Leong KW. Chronic Opioid Treatment Arrests Neurodevelopment and Alters Synaptic Activity in Human Midbrain Organoids. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400847. [PMID: 38549185 PMCID: PMC11151039 DOI: 10.1002/advs.202400847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Indexed: 06/06/2024]
Abstract
Understanding the impact of long-term opioid exposure on the embryonic brain is critical due to the surging number of pregnant mothers with opioid dependency. However, this has been limited by human brain inaccessibility and cross-species differences in animal models. Here, a human midbrain model is established that uses hiPSC-derived midbrain organoids to assess cell-type-specific responses to acute and chronic fentanyl treatment and fentanyl withdrawal. Single-cell mRNA sequencing of 25,510 cells from organoids in different treatment groups reveals that chronic fentanyl treatment arrests neuronal subtype specification during early midbrain development and alters synaptic activity and neuron projection. In contrast, acute fentanyl treatment increases dopamine release but does not significantly alter gene expression related to cell lineage development. These results provide the first examination of the effects of opioid exposure on human midbrain development at the single-cell level.
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Affiliation(s)
- Hye Sung Kim
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
- Institute of Tissue Regeneration Engineering (ITREN)Dankook UniversityCheonan31116Republic of Korea
- Mechanobiology Dental Medicine Research CenterDankook UniversityCheonan31116Republic of Korea
- Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative MedicineDankook UniversityCheonan31116Republic of Korea
| | - Yang Xiao
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
| | - Xuejing Chen
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
- Department of PhysicsTsinghua UniversityBeijing100084China
| | - Siyu He
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
| | - Jongwon Im
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
| | - Moshe J. Willner
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
| | - Michael O. Finlayson
- Single Cell Analysis CoreJP Sulzberger Columbia Genome CenterColumbia University Irving Medical CenterNew YorkNY10032USA
| | - Cong Xu
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
| | - Huixiang Zhu
- Department of PsychiatryColumbia University Medical CenterNew YorkNY10032USA
| | - Se Joon Choi
- Department of PsychiatryColumbia University Medical CenterNew YorkNY10032USA
- Division of Molecular TherapeuticsNew York State Psychiatric InstituteNew YorkNY10032USA
| | - Eugene V. Mosharov
- Department of PsychiatryColumbia University Medical CenterNew YorkNY10032USA
- Division of Molecular TherapeuticsNew York State Psychiatric InstituteNew YorkNY10032USA
| | - Hae‐Won Kim
- Institute of Tissue Regeneration Engineering (ITREN)Dankook UniversityCheonan31116Republic of Korea
- Mechanobiology Dental Medicine Research CenterDankook UniversityCheonan31116Republic of Korea
- Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative MedicineDankook UniversityCheonan31116Republic of Korea
| | - Bin Xu
- Department of PsychiatryColumbia University Medical CenterNew YorkNY10032USA
| | - Kam W. Leong
- Department of Biomedical EngineeringColumbia UniversityNew YorkNY10027USA
- Department of Systems BiologyColumbia University Irving Medical CenterNew YorkNY10032USA
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5
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Sandoval A, Duran P, Corzo-López A, Fernández-Gallardo M, Muñoz-Herrera D, Leyva-Leyva M, González-Ramírez R, Felix R. The role of voltage-gated calcium channels in the pathogenesis of Parkinson's disease. Int J Neurosci 2024; 134:452-461. [PMID: 35993158 DOI: 10.1080/00207454.2022.2115905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 06/07/2022] [Accepted: 07/29/2022] [Indexed: 10/15/2022]
Abstract
Aim: Voltage-gated calcium (CaV) channels play an essential role in maintaining calcium homeostasis and regulating numerous physiological processes in neurons. Therefore, dysregulation of calcium signaling is relevant in many neurological disorders, including Parkinson's disease (PD). This review aims to introduce the role of CaV channels in PD and discuss some novel aspects of channel regulation and its impact on the molecular pathophysiology of the disease. Methods: an exhaustive search of the literature in the field was carried out using the PubMed database of The National Center for Biotechnology Information. Systematic searches were performed from the initial date of publication to May 2022. Results: Although α-synuclein aggregates are the main feature of PD, L-type calcium (CaV1) channels seem to play an essential role in the pathogenesis of PD. Changes in the functional expression of CaV1.3 channels alter Calcium homeostasis and contribute to the degeneration of dopaminergic neurons. Furthermore, recent studies suggest that CaV channel trafficking towards the cell membrane depends on the activity of the ubiquitin-proteasome system (UPS). In PD, there is an increase in the expression of L-type channels associated with a decrease in the expression of Parkin, an E3 enzyme of the UPS. Therefore, a link between Parkin and CaV channels could play a fundamental role in the pathogenesis of PD and, as such, could be a potentially attractive target for therapeutic intervention. Conclusion: The study of alterations in the functional expression of CaV channels will provide a framework to understand better the neurodegenerative processes that occur in PD and a possible path toward identifying new therapeutic targets to treat this condition.
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Affiliation(s)
- Alejandro Sandoval
- School of Medicine FES Iztacala, National Autonomous University of Mexico (UNAM), Tlalnepantla, Mexico
| | - Paz Duran
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Alejandra Corzo-López
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | | | - David Muñoz-Herrera
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Margarita Leyva-Leyva
- Department of Molecular Biology and Histocompatibility, "Dr. Manuel Gea González" General Hospital, Mexico City, Mexico
| | - Ricardo González-Ramírez
- Department of Molecular Biology and Histocompatibility, "Dr. Manuel Gea González" General Hospital, Mexico City, Mexico
| | - Ricardo Felix
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
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Ratan Y, Rajput A, Pareek A, Pareek A, Jain V, Sonia S, Farooqui Z, Kaur R, Singh G. Advancements in Genetic and Biochemical Insights: Unraveling the Etiopathogenesis of Neurodegeneration in Parkinson's Disease. Biomolecules 2024; 14:73. [PMID: 38254673 PMCID: PMC10813470 DOI: 10.3390/biom14010073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/15/2023] [Accepted: 12/28/2023] [Indexed: 01/24/2024] Open
Abstract
Parkinson's disease (PD) is the second most prevalent neurodegenerative movement disorder worldwide, which is primarily characterized by motor impairments. Even though multiple hypotheses have been proposed over the decades that explain the pathogenesis of PD, presently, there are no cures or promising preventive therapies for PD. This could be attributed to the intricate pathophysiology of PD and the poorly understood molecular mechanism. To address these challenges comprehensively, a thorough disease model is imperative for a nuanced understanding of PD's underlying pathogenic mechanisms. This review offers a detailed analysis of the current state of knowledge regarding the molecular mechanisms underlying the pathogenesis of PD, with a particular emphasis on the roles played by gene-based factors in the disease's development and progression. This study includes an extensive discussion of the proteins and mutations of primary genes that are linked to PD, including α-synuclein, GBA1, LRRK2, VPS35, PINK1, DJ-1, and Parkin. Further, this review explores plausible mechanisms for DAergic neural loss, non-motor and non-dopaminergic pathologies, and the risk factors associated with PD. The present study will encourage the related research fields to understand better and analyze the current status of the biochemical mechanisms of PD, which might contribute to the design and development of efficacious and safe treatment strategies for PD in future endeavors.
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Affiliation(s)
- Yashumati Ratan
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Aishwarya Rajput
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Ashutosh Pareek
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Aaushi Pareek
- Department of Pharmacy, Banasthali Vidyapith, Banasthali 304022, Rajasthan, India; (A.R.); (A.P.); (A.P.)
| | - Vivek Jain
- Department of Pharmaceutical Sciences, Mohan Lal Sukhadia University, Udaipur 313001, Rajasthan, India;
| | - Sonia Sonia
- Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar 143005, Punjab, India;
| | - Zeba Farooqui
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA;
| | - Ranjeet Kaur
- Adesh Institute of Dental Sciences and Research, Bathinda 151101, Punjab, India;
| | - Gurjit Singh
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA;
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Ramezani M, Wagenknecht-Wiesner A, Wang T, Holowka DA, Eliezer D, Baird BA. Alpha synuclein modulates mitochondrial Ca 2+ uptake from ER during cell stimulation and under stress conditions. NPJ Parkinsons Dis 2023; 9:137. [PMID: 37741841 PMCID: PMC10518018 DOI: 10.1038/s41531-023-00578-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 09/08/2023] [Indexed: 09/25/2023] Open
Abstract
Alpha synuclein (a-syn) is an intrinsically disordered protein prevalent in neurons, and aggregated forms are associated with synucleinopathies including Parkinson's disease (PD). Despite the biomedical importance and extensive studies, the physiological role of a-syn and its participation in etiology of PD remain uncertain. We showed previously in model RBL cells that a-syn colocalizes with mitochondrial membranes, depending on formation of N-terminal helices and increasing with mitochondrial stress1. We have now characterized this colocalization and functional correlates in RBL, HEK293, and N2a cells. We find that expression of a-syn enhances stimulated mitochondrial uptake of Ca2+ from the ER, depending on formation of its N-terminal helices but not on its disordered C-terminal tail. Our results are consistent with a-syn acting as a tether between mitochondria and ER, and we show increased contacts between these two organelles using structured illumination microscopy. We tested mitochondrial stress caused by toxins related to PD, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP+) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and found that a-syn prevents recovery of stimulated mitochondrial Ca2+ uptake. The C-terminal tail, and not N-terminal helices, is involved in this inhibitory activity, which is abrogated when phosphorylation site serine-129 is mutated (S129A). Correspondingly, we find that MPTP/MPP+ and CCCP stress is accompanied by both phosphorylation (pS129) and aggregation of a-syn. Overall, our results indicate that a-syn can participate as a tethering protein to modulate Ca2+ flux between ER and mitochondria, with potential physiological significance. A-syn can also prevent cellular recovery from toxin-induced mitochondrial dysfunction, which may represent a pathological role of a-syn in the etiology of PD.
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Affiliation(s)
- Meraj Ramezani
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | | | - Tong Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - David A Holowka
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY, 10065, USA.
| | - Barbara A Baird
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA.
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Chawla S, Ahmadpour D, Schneider KL, Kumar N, Fischbach A, Molin M, Nystrom T. Calcineurin stimulation by Cnb1p overproduction mitigates protein aggregation and α-synuclein toxicity in a yeast model of synucleinopathy. Cell Commun Signal 2023; 21:220. [PMID: 37620860 PMCID: PMC10464345 DOI: 10.1186/s12964-023-01242-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 07/22/2023] [Indexed: 08/26/2023] Open
Abstract
The calcium-responsive phosphatase, calcineurin, senses changes in Ca2+ concentrations in a calmodulin-dependent manner. Here we report that under non-stress conditions, inactivation of calcineurin signaling or deleting the calcineurin-dependent transcription factor CRZ1 triggered the formation of chaperone Hsp100p (Hsp104p)-associated protein aggregates in Saccharomyces cerevisiae. Furthermore, calcineurin inactivation aggravated α-Synuclein-related cytotoxicity. Conversely, elevated production of the calcineurin activator, Cnb1p, suppressed protein aggregation and cytotoxicity associated with the familial Parkinson's disease-related mutant α-Synuclein A53T in a partly CRZ1-dependent manner. Activation of calcineurin boosted normal localization of both wild type and mutant α-synuclein to the plasma membrane, an intervention previously shown to mitigate α-synuclein toxicity in Parkinson's disease models. The findings demonstrate that calcineurin signaling, and Ca2+ influx to the vacuole, limit protein quality control in non-stressed cells and may have implications for elucidating to which extent aberrant calcineurin signaling contributes to the progression of Parkinson's disease(s) and other synucleinopathies. Video Abstract.
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Affiliation(s)
- Srishti Chawla
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, 405 30, Sweden.
- Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden.
| | - Doryaneh Ahmadpour
- Center for Bionics and Pain Research, Sahlgrenska University Hospital, Mölndal, 431 30, Sweden
| | - Kara L Schneider
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, 405 30, Sweden
| | - Navinder Kumar
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, 405 30, Sweden
| | - Arthur Fischbach
- Max Planck Institute for Biology of Ageing, Cologne, 50931, Germany
| | - Mikael Molin
- Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Thomas Nystrom
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, 405 30, Sweden.
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Nanclares C, Poynter J, Martell-Martinez HA, Vermilyea S, Araque A, Kofuji P, Lee MK, Covelo A. Dysregulation of astrocytic Ca 2+ signaling and gliotransmitter release in mouse models of α-synucleinopathies. Acta Neuropathol 2023; 145:597-610. [PMID: 36764943 PMCID: PMC10119048 DOI: 10.1007/s00401-023-02547-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/17/2023] [Accepted: 02/01/2023] [Indexed: 02/12/2023]
Abstract
α-Synuclein is a major component of Lewy bodies (LB) and Lewy neurites (LN) appearing in the postmortem brain of Parkinson's disease (PD) and other α-synucleinopathies. While most studies of α-synucleinopathies have focused on neuronal and synaptic alterations as well as dysfunctions of the astrocytic homeostatic roles, whether the bidirectional astrocyte-neuronal communication is affected in these diseases remains unknown. We have investigated whether the astrocyte Ca2+ excitability and the glutamatergic gliotransmission underlying astrocyte-neuronal signaling are altered in several transgenic mouse models related to α-synucleinopathies, i.e., mice expressing high and low levels of the human A53T mutant α-synuclein (G2-3 and H5 mice, respectively) globally or selectively in neurons (iSyn mice), mice expressing human wildtype α-synuclein (I2-2 mice), and mice expressing A30P mutant α-synuclein (O2 mice). Combining astrocytic Ca2+ imaging and neuronal electrophysiological recordings in hippocampal slices of these mice, we have found that compared to non-transgenic mice, astrocytes in G2-3 mice at different ages (1-6 months) displayed a Ca2+ hyperexcitability that was independent of neurotransmitter receptor activation, suggesting that the expression of α-synuclein mutant A53T altered the intrinsic properties of astrocytes. Similar dysregulation of the astrocyte Ca2+ signal was present in H5 mice, but not in I2-2 and O2 mice, indicating α-synuclein mutant-specific effects. Moreover, astrocyte Ca2+ hyperexcitability was absent in mice expressing the α-synuclein mutant A53T selectively in neurons, indicating that the effects on astrocytes were cell-autonomous. Consistent with these effects, glutamatergic gliotransmission was enhanced in G2-3 and H5 mice, but was unaffected in I2-2, O2 and iSyn mice. These results indicate a cell-autonomous effect of pathogenic A53T expression in astrocytes that may contribute to the altered neuronal and synaptic function observed in α-synucleinopathies.
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Affiliation(s)
- Carmen Nanclares
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Jonah Poynter
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Hector A Martell-Martinez
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Scott Vermilyea
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, Minneapolis, MN, 55455, USA
| | - Alfonso Araque
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Paulo Kofuji
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA.
| | - Michael K Lee
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA.
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, Minneapolis, MN, 55455, USA.
| | - Ana Covelo
- Department of Neuroscience, University of Minnesota, 4-125 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA.
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1215 NeuroCentre Magendie, 33077, Bordeaux, France.
- University of Bordeaux, 33077, Bordeaux, France.
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Ramezani M, Wagenknecht-Wiesner A, Wang T, Holowka DA, Eliezer D, Baird BA. Alpha Synuclein Modulates Mitochondrial Ca 2+ Uptake from ER During Cell Stimulation and Under Stress Conditions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.23.537965. [PMID: 37163091 PMCID: PMC10168219 DOI: 10.1101/2023.04.23.537965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Alpha synuclein (a-syn) is an intrinsically disordered protein prevalent in neurons, and aggregated forms are associated with synucleinopathies including Parkinson' disease (PD). Despite the biomedical importance and extensive studies, the physiological role of a-syn and its participation in etiology of PD remain uncertain. We showed previously in model RBL cells that a-syn colocalizes with mitochondrial membranes, depending on formation of N-terminal helices and increasing with mitochondrial stress. 1 We have now characterized this colocalization and functional correlates in RBL, HEK293, and N2a cells. We find that expression of a-syn enhances stimulated mitochondrial uptake of Ca 2+ from the ER, depending on formation of its N-terminal helices but not on its disordered C-terminal tail. Our results are consistent with a-syn acting as a tether between mitochondria and ER, and we show increased contacts between these two organelles using structured illumination microscopy. We tested mitochondrial stress caused by toxins related to PD, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP+) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP), and found that a-syn prevents recovery of stimulated mitochondrial Ca 2+ uptake. The C-terminal tail, and not N-terminal helices, is involved in this inhibitory activity, which is abrogated when phosphorylation site serine-129 is mutated (S129A). Correspondingly, we find that MPTP/MPP+ and CCCP stress is accompanied by both phosphorylation (pS129) and aggregation of a-syn. Overall, our results indicate that a-syn can participate as a tethering protein to modulate Ca 2+ flux between ER and mitochondria, with potential physiological significance. A-syn can also prevent cellular recovery from toxin-induced mitochondrial dysfunction, which may represent a pathological role of a-syn in the etiology of PD.
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Affiliation(s)
- Meraj Ramezani
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | | | - Tong Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | - David A. Holowka
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065
| | - Barbara A. Baird
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
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11
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Correa BH, Moreira CR, Hildebrand ME, Vieira LB. The Role of Voltage-Gated Calcium Channels in Basal Ganglia Neurodegenerative Disorders. Curr Neuropharmacol 2023; 21:183-201. [PMID: 35339179 PMCID: PMC10190140 DOI: 10.2174/1570159x20666220327211156] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/11/2022] [Accepted: 03/14/2022] [Indexed: 11/22/2022] Open
Abstract
Calcium (Ca2+) plays a central role in regulating many cellular processes and influences cell survival. Several mechanisms can disrupt Ca2+ homeostasis to trigger cell death, including oxidative stress, mitochondrial damage, excitotoxicity, neuroinflammation, autophagy, and apoptosis. Voltage-gated Ca2+ channels (VGCCs) act as the main source of Ca2+ entry into electrically excitable cells, such as neurons, and they are also expressed in glial cells such as astrocytes and oligodendrocytes. The dysregulation of VGCC activity has been reported in both Parkinson's disease (PD) and Huntington's (HD). PD and HD are progressive neurodegenerative disorders (NDs) of the basal ganglia characterized by motor impairment as well as cognitive and psychiatric dysfunctions. This review will examine the putative role of neuronal VGCCs in the pathogenesis and treatment of central movement disorders, focusing on PD and HD. The link between basal ganglia disorders and VGCC physiology will provide a framework for understanding the neurodegenerative processes that occur in PD and HD, as well as a possible path towards identifying new therapeutic targets for the treatment of these debilitating disorders.
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Affiliation(s)
- Bernardo H.M. Correa
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Carlos Roberto Moreira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Luciene Bruno Vieira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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12
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Mosharov EV, Lindau M. Patch Amperometry and Intracellular Patch Electrochemistry. Methods Mol Biol 2023; 2565:239-260. [PMID: 36205899 PMCID: PMC9910029 DOI: 10.1007/978-1-0716-2671-9_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Both patch amperometry (PA) and intracellular patch electrochemistry (IPE) take advantage of a recording configuration where an electrochemical detector-carbon fiber electrode (CFE)-is housed inside a patch pipette. PA, which is employed in cell-attached or excised inside-out patch clamp configuration, offers high-resolution patch capacitance measurements with simultaneous amperometric detection of catecholamines released during exocytosis. The method provides precise information on single-vesicle size and quantal content, fusion pore conductance, and permeability of the pore for catecholamines. IPE, on the other hand, measures cytosolic catecholamines that diffuse into the patch pipette following membrane rupture to achieve the whole-cell configuration. In amperometric mode, IPE detects total catechols, whereas in cyclic voltammetric mode, it provides more specific information on the nature of the detected molecules and may selectively quantify catecholamines, providing a direct approach to determine cytosolic concentrations of catecholaminergic transmitters and their metabolites. Here, we provide detailed instructions on setting up PA and IPE, performing experiments and analyzing the data.
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Affiliation(s)
- Eugene V. Mosharov
- Departments of Psychiatry and Neurology, Columbia University Medical Center, New York State Psychiatric Institute, New York, NY 10032
| | - Manfred Lindau
- Department of Physiology and Biophysics, University of Miami, Miller School of Medicine, Miami, FL, 33136
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13
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The complex role of inflammation and gliotransmitters in Parkinson's disease. Neurobiol Dis 2023; 176:105940. [PMID: 36470499 PMCID: PMC10372760 DOI: 10.1016/j.nbd.2022.105940] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 11/28/2022] [Accepted: 12/01/2022] [Indexed: 12/09/2022] Open
Abstract
Our understanding of the role of innate and adaptive immune cell function in brain health and how it goes awry during aging and neurodegenerative diseases is still in its infancy. Inflammation and immunological dysfunction are common components of Parkinson's disease (PD), both in terms of motor and non-motor components of PD. In recent decades, the antiquated notion that the central nervous system (CNS) in disease states is an immune-privileged organ, has been debunked. The immune landscape in the CNS influences peripheral systems, and peripheral immunological changes can alter the CNS in health and disease. Identifying immune and inflammatory pathways that compromise neuronal health and survival is critical in designing innovative and effective strategies to limit their untoward effects on neuronal health.
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14
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Park J, Jang KM, Park KK. Effects of Apamin on MPP +-Induced Calcium Overload and Neurotoxicity by Targeting CaMKII/ERK/p65/STAT3 Signaling Pathways in Dopaminergic Neuronal Cells. Int J Mol Sci 2022; 23:ijms232315255. [PMID: 36499581 PMCID: PMC9736188 DOI: 10.3390/ijms232315255] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/19/2022] [Accepted: 11/28/2022] [Indexed: 12/12/2022] Open
Abstract
Parkinson's disease (PD), a neurodegenerative disorder, is characterized by the loss of dopaminergic (DA) neurons. The pathogenesis of PD is associated with several factors including oxidative stress, inflammation, and mitochondrial dysfunction. Ca2+ signaling plays a vital role in neuronal signaling and altered Ca2+ homeostasis has been implicated in many neuronal diseases including PD. Recently, we reported that apamin (APM), a selective antagonist of the small-conductivity Ca2+-activated K+ (SK) channel, suppresses neuroinflammatory response. However, the mechanism(s) underlying the vulnerability of DA neurons were not fully understood. In this study, we investigated whether APM affected 1-methyl-4-phenyl pyridinium (MPP+)-mediated neurotoxicity in SH-SY5Y cells and rat embryo primary mesencephalic neurons. We found that APM decreased Ca2+ overload arising from MPP+-induced neurotoxicity response through downregulating the level of CaMKII, phosphorylation of ERK, and translocation of nuclear factor NFκB/signal transducer and activator of transcription (STAT)3. Furthermore, we showed that the correlation of MPP+-mediated Ca2+ overload and ERK/NFκB/STAT3 in the neurotoxicity responses, and dopaminergic neuronal cells loss, was verified through inhibitors. Our findings showed that APM might prevent loss of DA neurons via inhibition of Ca2+-overload-mediated signaling pathway and provide insights regarding the potential use of APM in treating neurodegenerative diseases.
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Affiliation(s)
- Jihyun Park
- Department of Pathology, College of Medicine, Catholic University of Daegu, Daegu 42472, Republic of Korea
| | - Kyung Mi Jang
- Department of Pediatrics, College of Medicine, Yeungnam University, Daegu 42415, Republic of Korea
| | - Kwan-Kyu Park
- Department of Pathology, College of Medicine, Catholic University of Daegu, Daegu 42472, Republic of Korea
- Correspondence: ; Tel.: +82-53-650-4149
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15
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Interactions of dopamine, iron, and alpha-synuclein linked to dopaminergic neuron vulnerability in Parkinson's disease and neurodegeneration with brain iron accumulation disorders. Neurobiol Dis 2022; 175:105920. [DOI: 10.1016/j.nbd.2022.105920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 10/21/2022] [Accepted: 11/04/2022] [Indexed: 11/08/2022] Open
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Zhang J, Shen Q, Ma Y, Liu L, Jia W, Chen L, Xie J. Calcium Homeostasis in Parkinson's Disease: From Pathology to Treatment. Neurosci Bull 2022; 38:1267-1270. [PMID: 35727497 PMCID: PMC9554109 DOI: 10.1007/s12264-022-00899-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 05/06/2022] [Indexed: 11/25/2022] Open
Affiliation(s)
- Jingxian Zhang
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China
| | - Qingqing Shen
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China
| | - Yue Ma
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China
| | - Lin Liu
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China
| | - Wenting Jia
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China
| | - Leilei Chen
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China.
| | - Junxia Xie
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, 266071, China.
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17
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Network Pharmacology and Molecular Docking Analyses Unveil the Mechanisms of Yiguanjian Decoction against Parkinson’s Disease from Inner/Outer Brain Perspective. BIOMED RESEARCH INTERNATIONAL 2022; 2022:4758189. [PMID: 36237735 PMCID: PMC9552692 DOI: 10.1155/2022/4758189] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/06/2022] [Accepted: 09/14/2022] [Indexed: 11/18/2022]
Abstract
Objective This study aims to explore the pharmacodynamic mechanism of Yiguanjian (YGJ) decoction against Parkinson's disease (PD) through integrating the central nervous (inner brain) and peripheral system (outer brain) relationship spectrum. Methods The active components of YGJ were achieved from the TCMSP, TCMID, and TCM@Taiwan databases. The blood-brain barrier (BBB) permeability of the active components along with their corresponding targets was evaluated utilizing the existing website, namely, SwissADME and SwissTargetPrediction. The targets of PD were determined through database retrieval. The interaction network was constructed upon the STRING database, followed by the visualization using Cytoscape software. Then, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on potential targets. Finally, the molecular docking approach was employed to assess the binding affinity between key components and key targets. Results Overall, we identified 79 active components, 128 potential targets of YGJ, and 97 potential targets of YGJ-BBB potentially suitable for the treatment of PD. GO and KEGG analyses showed that the YGJ treatment of PD mainly relied on PI3K-Akt pathway while the YGJ-BBB was mostly involved in endocrine resistance. The molecular docking results displayed high affinity between multiple compounds and targets in accordance with previous observations. Conclusions Our study unveiled the potential mechanisms of YGJ against PD from a systemic perspective: (1) for the YGJ, they have potential exerting effects on the peripheral system and inhibiting neuronal apoptosis through regulating the PI3K-Akt pathway; (2) for the YGJ-BBB, they can directly modulate endocrine resistance of the central nervous and holistically enhance body resistance to PD along with YGJ on PI3K-Akt pathway.
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18
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Burke S, Trudeau LE. Axonal Domain Structure as a Putative Identifier of Neuron-Specific Vulnerability to Oxidative Stress in Cultured Neurons. eNeuro 2022; 9:ENEURO.0139-22.2022. [PMID: 36192156 PMCID: PMC9595591 DOI: 10.1523/eneuro.0139-22.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 08/30/2022] [Accepted: 09/16/2022] [Indexed: 12/15/2022] Open
Abstract
Several populations of neurons are purported to degenerate in Parkinson's disease (PD). One current hypothesis suggests that vulnerable neurons in PD share common characteristics including projecting to voluminous territories and having extremely long and branched axonal domains with large numbers of neurotransmitter release sites. In this study, we used a mouse in vitro culture system to compare the axonal domain of neuronal populations suspected to be vulnerable in PD to that of neuronal populations considered at a lesser risk. In the first category, we included dopamine (DA) neurons of the substantia nigra, noradrenergic neurons of the locus coeruleus (LC), serotonin neurons of the raphe nuclei (R), and cholinergic neurons of the dorsal motor nucleus of the vagus (DMV). In the second category, we included DA neurons of the ventral tegmental area, cholinergic neurons of the hypoglossal nucleus, and cholinergic interneurons of the dorsal striatum. Validating their differential vulnerability, we find that, when compared with neurons presumed to be resilient in PD, a larger proportion of neurons presumed to be vulnerable in PD degenerate in response to cell stress induced by hydrogen peroxide. We also find that they are endowed with larger axonal domains, that are more complex, have more axonal varicosities with a higher proportion of varicosities that are positive for synaptotagmin 1 (Syt-1). Notwithstanding the obvious limitations related to the dissection of small brain nuclei and to the growth of these neurons in vitro, these findings support the hypothesis that axonal domain structure is a key characteristic of neuronal vulnerability to oxidative stress.
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Affiliation(s)
- Samuel Burke
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, Quebec, H3T 1J4, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, Quebec, H3T 1J4, Canada
- Neural Signaling and Circuitry Research Group (SNC), Montréal, Quebec, H3T 1J4, Canada
- Center for Interdisciplinary Research on the Brain and Learning (CIRCA), Montréal, Quebec, H3T 1J4
| | - Louis-Eric Trudeau
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, Quebec, H3T 1J4, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, Quebec, H3T 1J4, Canada
- Neural Signaling and Circuitry Research Group (SNC), Montréal, Quebec, H3T 1J4, Canada
- Center for Interdisciplinary Research on the Brain and Learning (CIRCA), Montréal, Quebec, H3T 1J4
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19
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Kulkarni AS, Burns MR, Brundin P, Wesson DW. Linking α-synuclein-induced synaptopathy and neural network dysfunction in early Parkinson's disease. Brain Commun 2022; 4:fcac165. [PMID: 35822101 PMCID: PMC9272065 DOI: 10.1093/braincomms/fcac165] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/11/2022] [Accepted: 06/20/2022] [Indexed: 01/18/2023] Open
Abstract
The prodromal phase of Parkinson's disease is characterized by aggregation of the misfolded pathogenic protein α-synuclein in select neural centres, co-occurring with non-motor symptoms including sensory and cognitive loss, and emotional disturbances. It is unclear whether neuronal loss is significant during the prodrome. Underlying these symptoms are synaptic impairments and aberrant neural network activity. However, the relationships between synaptic defects and network-level perturbations are not established. In experimental models, pathological α-synuclein not only impacts neurotransmission at the synaptic level, but also leads to changes in brain network-level oscillatory dynamics-both of which likely contribute to non-motor deficits observed in Parkinson's disease. Here we draw upon research from both human subjects and experimental models to propose a 'synapse to network prodrome cascade' wherein before overt cell death, pathological α-synuclein induces synaptic loss and contributes to aberrant network activity, which then gives rise to prodromal symptomology. As the disease progresses, abnormal patterns of neural activity ultimately lead to neuronal loss and clinical progression of disease. Finally, we outline goals and research needed to unravel the basis of functional impairments in Parkinson's disease and other α-synucleinopathies.
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Affiliation(s)
- Aishwarya S Kulkarni
- Department of Pharmacology & Therapeutics, University of Florida, 1200 Newell Dr, Gainesville, FL 32610, USA
| | - Matthew R Burns
- Department of Neurology, University of Florida, 1200 Newell Dr, Gainesville, FL 32610, USA
- Norman Fixel Institute for Neurological Disorders, University of Florida, 1200 Newell Dr, Gainesville, FL 32610, USA
| | - Patrik Brundin
- Pharma Research and Early Development (pRED), F. Hoffman-La Roche, Little Falls, NJ, USA
| | - Daniel W Wesson
- Department of Pharmacology & Therapeutics, University of Florida, 1200 Newell Dr, Gainesville, FL 32610, USA
- Norman Fixel Institute for Neurological Disorders, University of Florida, 1200 Newell Dr, Gainesville, FL 32610, USA
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20
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Chalazonitis A, Rao M, Sulzer D. Similarities and differences between nigral and enteric dopaminergic neurons unravel distinctive involvement in Parkinson's disease. NPJ Parkinsons Dis 2022; 8:50. [PMID: 35459867 PMCID: PMC9033791 DOI: 10.1038/s41531-022-00308-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 03/14/2022] [Indexed: 11/09/2022] Open
Abstract
In addition to the well-known degeneration of midbrain dopaminergic neurons, enteric neurons can also be affected in neurodegenerative disorders such as Parkinson's disease (PD). Dopaminergic neurons have recently been identified in the enteric nervous system (ENS). While ENS dopaminergic neurons have been shown to degenerate in genetic mouse models of PD, analyses of their survival in enteric biopsies of PD patients have provided inconsistent results to date. In this context, this review seeks to highlight the distinctive and shared factors and properties that control the evolution of these two sets of dopaminergic neurons from neuronal precursors to aging neurons. Although their cellular sources and developmental times of origin differ, midbrain and ENS dopaminergic neurons express many transcription factors in common and their respective environments express similar neurotrophic molecules. For example, Foxa2 and Sox6 are expressed by both populations to promote the specification, differentiation, and long-term maintenance of the dopaminergic phenotype. Both populations exhibit sustained patterns of excitability that drive intrinsic vulnerability over time. In disorders such as PD, colon biopsies have revealed aggregation of alpha-synuclein in the submucosal plexus where dopaminergic neurons reside and lack blood barrier protection. Thus, these enteric neurons may be more susceptible to neurotoxic insults and aggregation of α-synuclein that spreads from gut to midbrain. Under sustained stress, inefficient autophagy leads to neurodegeneration, GI motility dysfunction, and PD symptoms. Recent findings suggest that novel neurotrophic factors such as CDNF have the potential to be used as neuroprotective agents to prevent and treat ENS symptoms of PD.
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Affiliation(s)
- Alcmène Chalazonitis
- Department of Pathology & Cell Biology, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY, USA.
| | - Meenakshi Rao
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - David Sulzer
- Departments of Psychiatry, Neurology, and Pharmacology, Division of Molecular Therapeutics, New York State Psychiatry Institute, Columbia University, New York, NY, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815, USA
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21
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George DS, Hackelberg S, Jayaraj ND, Ren D, Edassery SL, Rathwell CA, Miller RE, Malfait AM, Savas JN, Miller RJ, Menichella DM. Mitochondrial calcium uniporter deletion prevents painful diabetic neuropathy by restoring mitochondrial morphology and dynamics. Pain 2022; 163:560-578. [PMID: 34232927 PMCID: PMC8720329 DOI: 10.1097/j.pain.0000000000002391] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 05/25/2021] [Accepted: 06/18/2021] [Indexed: 01/11/2023]
Abstract
ABSTRACT Painful diabetic neuropathy (PDN) is an intractable complication affecting 25% of diabetic patients. Painful diabetic neuropathy is characterized by neuropathic pain accompanied by dorsal root ganglion (DRG) nociceptor hyperexcitability, resulting in calcium overload, axonal degeneration, and loss of cutaneous innervation. The molecular pathways underlying these effects are unknown. Using high-throughput and deep-proteome profiling, we found that mitochondrial fission proteins were elevated in DRG neurons from mice with PDN induced by a high-fat diet (HFD). In vivo calcium imaging revealed increased calcium signaling in DRG nociceptors from mice with PDN. Furthermore, using electron microscopy, we showed that mitochondria in DRG nociceptors had fragmented morphology as early as 2 weeks after starting HFD, preceding the onset of mechanical allodynia and small-fiber degeneration. Moreover, preventing calcium entry into the mitochondria, by selectively deleting the mitochondrial calcium uniporter from these neurons, restored normal mitochondrial morphology, prevented axonal degeneration, and reversed mechanical allodynia in the HFD mouse model of PDN. These studies suggest a molecular cascade linking neuropathic pain to axonal degeneration in PDN. In particular, nociceptor hyperexcitability and the associated increased intracellular calcium concentrations could lead to excessive calcium entry into mitochondria mediated by the mitochondrial calcium uniporter, resulting in increased calcium-dependent mitochondrial fission and ultimately contributing to small-fiber degeneration and neuropathic pain in PDN. Hence, we propose that targeting calcium entry into nociceptor mitochondria may represent a promising effective and disease-modifying therapeutic approach for this currently intractable and widespread affliction. Moreover, these results are likely to inform studies of other neurodegenerative disease involving similar underlying events.
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Affiliation(s)
| | | | | | - Dongjun Ren
- Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | | | - Craig A. Rathwell
- Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Rachel E. Miller
- Department of Internal Medicine, Rush Medical College, Chicago, IL, United States
| | - Anne-Marie Malfait
- Department of Internal Medicine, Rush Medical College, Chicago, IL, United States
| | | | - Richard J. Miller
- Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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22
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Abstract
The notion that autoimmune responses to α-synuclein may be involved in the pathogenesis of this disorder stems from reports that mutations in α-synuclein or certain alleles of the major histocompatibility complex (MHC) are associated with the disease and that dopaminergic and norepinephrinergic neurons in the midbrain can present antigenic epitopes. Here, we discuss recent evidence that a defined set of peptides derived from α-synuclein act as antigenic epitopes displayed by specific MHC alleles and drive helper and cytotoxic T cell responses in patients with PD. Moreover, phosphorylated α-synuclein may activate T cell responses in a less restricted manner in PD. While the roles for the acquired immune system in disease pathogenesis remain unknown, preclinical animal models and in vitro studies indicate that T cells may interact with neurons and exert effects related to neuronal death and neuroprotection. These findings suggest that therapeutics that target T cells and ameliorate the incidence or disease severity of inflammatory bowel disorders or CNS autoimmune diseases such as multiple sclerosis may be useful in PD.
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23
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Habernig L, Broeskamp F, Aufschnaiter A, Diessl J, Peselj C, Urbauer E, Eisenberg T, de Ory A, Büttner S. Ca2+ administration prevents α-synuclein proteotoxicity by stimulating calcineurin-dependent lysosomal proteolysis. PLoS Genet 2021; 17:e1009911. [PMID: 34780474 PMCID: PMC8629384 DOI: 10.1371/journal.pgen.1009911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 11/29/2021] [Accepted: 10/25/2021] [Indexed: 12/02/2022] Open
Abstract
The capacity of a cell to maintain proteostasis progressively declines during aging. Virtually all age-associated neurodegenerative disorders associated with aggregation of neurotoxic proteins are linked to defects in the cellular proteostasis network, including insufficient lysosomal hydrolysis. Here, we report that proteotoxicity in yeast and Drosophila models for Parkinson's disease can be prevented by increasing the bioavailability of Ca2+, which adjusts intracellular Ca2+ handling and boosts lysosomal proteolysis. Heterologous expression of human α-synuclein (αSyn), a protein critically linked to Parkinson's disease, selectively increases total cellular Ca2+ content, while the levels of manganese and iron remain unchanged. Disrupted Ca2+ homeostasis results in inhibition of the lysosomal protease cathepsin D and triggers premature cellular and organismal death. External administration of Ca2+ reduces αSyn oligomerization, stimulates cathepsin D activity and in consequence restores survival, which critically depends on the Ca2+/calmodulin-dependent phosphatase calcineurin. In flies, increasing the availability of Ca2+ discloses a neuroprotective role of αSyn upon manganese overload. In sum, we establish a molecular interplay between cathepsin D and calcineurin that can be activated by Ca2+ administration to counteract αSyn proteotoxicity.
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Affiliation(s)
- Lukas Habernig
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Filomena Broeskamp
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Andreas Aufschnaiter
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Jutta Diessl
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Carlotta Peselj
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Elisabeth Urbauer
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Tobias Eisenberg
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- BioTechMed Graz, Graz, Austria
- Field of Excellence BioHealth–University of Graz, Graz, Austria
| | - Ana de Ory
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Sabrina Büttner
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
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24
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Paß T, Wiesner RJ, Pla-Martín D. Selective Neuron Vulnerability in Common and Rare Diseases-Mitochondria in the Focus. Front Mol Biosci 2021; 8:676187. [PMID: 34295920 PMCID: PMC8290884 DOI: 10.3389/fmolb.2021.676187] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/08/2021] [Indexed: 12/12/2022] Open
Abstract
Mitochondrial dysfunction is a central feature of neurodegeneration within the central and peripheral nervous system, highlighting a strong dependence on proper mitochondrial function of neurons with especially high energy consumptions. The fitness of mitochondria critically depends on preservation of distinct processes, including the maintenance of their own genome, mitochondrial dynamics, quality control, and Ca2+ handling. These processes appear to be differently affected in common neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, as well as in rare neurological disorders, including Huntington’s disease, Amyotrophic Lateral Sclerosis and peripheral neuropathies. Strikingly, particular neuron populations of different morphology and function perish in these diseases, suggesting that cell-type specific factors contribute to the vulnerability to distinct mitochondrial defects. Here we review the disruption of mitochondrial processes in common as well as in rare neurological disorders and its impact on selective neurodegeneration. Understanding discrepancies and commonalities regarding mitochondrial dysfunction as well as individual neuronal demands will help to design new targets and to make use of already established treatments in order to improve treatment of these diseases.
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Affiliation(s)
- Thomas Paß
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Cologne, Cologne, Germany
| | - Rudolf J Wiesner
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - David Pla-Martín
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Cologne, Cologne, Germany
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25
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Miller DR, Guenther DT, Maurer AP, Hansen CA, Zalesky A, Khoshbouei H. Dopamine Transporter Is a Master Regulator of Dopaminergic Neural Network Connectivity. J Neurosci 2021; 41:5453-5470. [PMID: 33980544 PMCID: PMC8221606 DOI: 10.1523/jneurosci.0223-21.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/19/2021] [Accepted: 05/01/2021] [Indexed: 12/13/2022] Open
Abstract
Dopaminergic neurons of the substantia nigra pars compacta (SNC) and ventral tegmental area (VTA) exhibit spontaneous firing activity. The dopaminergic neurons in these regions have been shown to exhibit differential sensitivity to neuronal loss and psychostimulants targeting dopamine transporter. However, it remains unclear whether these regional differences scale beyond individual neuronal activity to regional neuronal networks. Here, we used live-cell calcium imaging to show that network connectivity greatly differs between SNC and VTA regions with higher incidence of hub-like neurons in the VTA. Specifically, the frequency of hub-like neurons was significantly lower in SNC than in the adjacent VTA, consistent with the interpretation of a lower network resilience to SNC neuronal loss. We tested this hypothesis, in DAT-cre/loxP-GCaMP6f mice of either sex, when activity of an individual dopaminergic neuron is suppressed, through whole-cell patch clamp electrophysiology, in either SNC or VTA networks. Neuronal loss in the SNC increased network clustering, whereas the larger number of hub-neurons in the VTA overcompensated by decreasing network clustering in the VTA. We further show that network properties are regulatable via a dopamine transporter but not a D2 receptor dependent mechanism. Our results demonstrate novel regulatory mechanisms of functional network topology in dopaminergic brain regions.SIGNIFICANCE STATEMENT In this work, we begin to untangle the differences in complex network properties between the substantia nigra pars compacta (SNC) and VTA, that may underlie differential sensitivity between regions. The methods and analysis employed provide a springboard for investigations of network topology in multiple deep brain structures and disorders.
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Affiliation(s)
- Douglas R Miller
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - Dylan T Guenther
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - Andrew P Maurer
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - Carissa A Hansen
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - Andrew Zalesky
- Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, Melbourne, Victoria 3010, Australia
- Department of Biomedical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia
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26
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Ortner NJ. Voltage-Gated Ca 2+ Channels in Dopaminergic Substantia Nigra Neurons: Therapeutic Targets for Neuroprotection in Parkinson's Disease? Front Synaptic Neurosci 2021; 13:636103. [PMID: 33716705 PMCID: PMC7952618 DOI: 10.3389/fnsyn.2021.636103] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/25/2021] [Indexed: 12/21/2022] Open
Abstract
The loss of dopamine (DA)-producing neurons in the substantia nigra pars compacta (SN) underlies the core motor symptoms of the progressive movement disorder Parkinson's disease (PD). To date, no treatment to prevent or slow SN DA neurodegeneration exists; thus, the identification of the underlying factors contributing to the high vulnerability of these neurons represents the basis for the development of novel therapies. Disrupted Ca2+ homeostasis and mitochondrial dysfunction seem to be key players in the pathophysiology of PD. The autonomous pacemaker activity of SN DA neurons, in combination with low cytosolic Ca2+ buffering, leads to large somatodendritic fluctuations of intracellular Ca2+ levels that are linked to elevated mitochondrial oxidant stress. L-type voltage-gated Ca2+ channels (LTCCs) contribute to these Ca2+ oscillations in dendrites, and LTCC inhibition was beneficial in cellular and in vivo animal models of PD. However, in a recently completed phase 3 clinical trial, the dihydropyridine (DHP) LTCC inhibitor isradipine failed to slow disease progression in early PD patients, questioning the feasibility of DHPs for PD therapy. Novel evidence also suggests that R- and T-type Ca2+ channels (RTCCs and TTCCs, respectively) represent potential PD drug targets. This short review aims to (re)evaluate the therapeutic potential of LTCC, RTCC, and TTCC inhibition in light of novel preclinical and clinical data and the feasibility of available Ca2+ channel blockers to modify PD disease progression. I also summarize their cell-specific roles for SN DA neuron function and describe how their gating properties allow activity (and thus their contribution to stressful Ca2+ oscillations) during pacemaking.
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Affiliation(s)
- Nadine J. Ortner
- Department of Pharmacology and Toxicology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
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27
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Minakaki G, Krainc D, Burbulla LF. The Convergence of Alpha-Synuclein, Mitochondrial, and Lysosomal Pathways in Vulnerability of Midbrain Dopaminergic Neurons in Parkinson's Disease. Front Cell Dev Biol 2020; 8:580634. [PMID: 33381501 PMCID: PMC7767856 DOI: 10.3389/fcell.2020.580634] [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: 07/06/2020] [Accepted: 11/10/2020] [Indexed: 12/15/2022] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by progressive bradykinesia, rigidity, resting tremor, and gait impairment, as well as a spectrum of non-motor symptoms including autonomic and cognitive dysfunction. The cardinal motor symptoms of PD stem from the loss of substantia nigra (SN) dopaminergic (DAergic) neurons, and it remains unclear why SN DAergic neurons are preferentially lost in PD. However, recent identification of several genetic PD forms suggests that mitochondrial and lysosomal dysfunctions play important roles in the degeneration of midbrain dopamine (DA) neurons. In this review, we discuss the interplay of cell-autonomous mechanisms linked to DAergic neuron vulnerability and alpha-synuclein homeostasis. Emerging studies highlight a deleterious feedback cycle, with oxidative stress, altered DA metabolism, dysfunctional lysosomes, and pathological alpha-synuclein species representing key events in the pathogenesis of PD. We also discuss the interactions of alpha-synuclein with toxic DA metabolites, as well as the biochemical links between intracellular iron, calcium, and alpha-synuclein accumulation. We suggest that targeting multiple pathways, rather than individual processes, will be important for developing disease-modifying therapies. In this context, we focus on current translational efforts specifically targeting lysosomal function, as well as oxidative stress via calcium and iron modulation. These efforts could have therapeutic benefits for the broader population of sporadic PD and related synucleinopathies.
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Affiliation(s)
- Georgia Minakaki
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Lena F Burbulla
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
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28
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Zampese E, Surmeier DJ. Calcium, Bioenergetics, and Parkinson's Disease. Cells 2020; 9:cells9092045. [PMID: 32911641 PMCID: PMC7564460 DOI: 10.3390/cells9092045] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022] Open
Abstract
Degeneration of substantia nigra (SN) dopaminergic (DAergic) neurons is responsible for the core motor deficits of Parkinson’s disease (PD). These neurons are autonomous pacemakers that have large cytosolic Ca2+ oscillations that have been linked to basal mitochondrial oxidant stress and turnover. This review explores the origin of Ca2+ oscillations and their role in the control of mitochondrial respiration, bioenergetics, and mitochondrial oxidant stress.
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29
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Verma A, Ray A, Bapat D, Diwakar L, Kommaddi RP, Schneider BL, Hirsch EC, Ravindranath V. Glutaredoxin 1 Downregulation in the Substantia Nigra Leads to Dopaminergic Degeneration in Mice. Mov Disord 2020; 35:1843-1853. [PMID: 32618039 DOI: 10.1002/mds.28190] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 06/02/2020] [Accepted: 06/08/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Parkinson's disease (PD) is characterized by a severe loss of the dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc). Perturbation of protein thiol redox homeostasis has been shown to play a role in the dysregulation of cell death and cell survival signaling pathways in these neurons. Glutaredoxin 1 (Grx1) is a thiol/disulfide oxidoreductase that catalyzes the deglutathionylation of proteins and is important for regulation of cellular protein thiol redox homeostasis. OBJECTIVES We evaluated if the downregulation of Grx1 could lead to dopaminergic degeneration and PD-relevant motor deficits in mice. METHODS Grx1 was downregulated unilaterally through viral vector-mediated transduction of short hairpin RNA against Grx1 into the SNpc. Behavioral assessment was performed through rotarod and elevated body swing test. Stereological analysis of tyrosine hydroxylase-positive and Nissl-positive neurons was carried out to evaluate neurodegeneration. RESULTS Downregulation of Grx1 resulted in contralateral bias of elevated body swing and reduced latency to fall off, accelerating rotarod. This was accompanied by a loss of tyrosine hydroxylase-positive neurons in the SNpc and their DA projections in the striatum. Furthermore, there was a loss Nissl-positive neurons in the SNpc, indicating cell death. This was selective to the SNpc neurons because DA neurons in the ventral tegmental area were unaffected akin to that seen in human PD. Furthermore, Grx1 mRNA expression was substantially decreased in the SNpc from PD patients. CONCLUSIONS Our study indicates that Grx1 is critical for the survival of SNpc DA neurons and that it is downregulated in human PD. © 2020 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Aditi Verma
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India
| | - Ajit Ray
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India
| | - Deepti Bapat
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India
| | - Latha Diwakar
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India.,Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Reddy Peera Kommaddi
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India.,Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Bernard L Schneider
- Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Etienne C Hirsch
- Institut du Cerveau-ICM Inserm U 1127, CNRS UMR 7225, Sorbonne Université, Paris, France
| | - Vijayalakshmi Ravindranath
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India.,Centre for Brain Research, Indian Institute of Science, Bangalore, India
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30
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Abdelwahab S, Elsebay SAG, Fouli Gaber M, Abdel-Hafez SMN. Comparative study between bone marrow mesenchymal stem cell and their conditioned medium in the treatment of rat model of Parkinsonism. J Cell Physiol 2020; 236:440-457. [PMID: 32557610 DOI: 10.1002/jcp.29872] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 05/30/2020] [Indexed: 12/17/2022]
Abstract
Parkinsonism is one of the most common aging neurodegenerative disorders. This study aims to compare the therapeutic effect of stem cell versus its conditioned medium in the Parkinsonism model. Parkinsonism was induced by daily subcutaneous injection of 0.5 mg/kg of rotenone dissolved in dimethyl sulfoxide for 28 days. Fifty rats were divided randomly into five groups: control, dimethyl sulfoxide, Parkinsonism, stem cell-treated, and conditioned medium-treated groups. Midbrain specimens were obtained for histological, immunohistochemical, and biochemical studies. Lewy bodies were observed in the Parkinsonism group in the dopaminergic neuron and neuropil as well. Almost all of the pathological changes were clearly ameliorated in both stem cell- and conditioned medium-treated groups as confirmed by biochemical, histological, and immunohistochemical (anti-nestin, anti-glial fibrillary acidic protein, and anti-α synuclein) studies. However, the conditioned medium showed more superior therapeutic effect establishing nearly the normal histological architecture of substantia nigra. These results may pave the future for using stem cell-conditioned medium as a more convenient and effective adjuvant therapy in Parkinsonism and other neurodegenerative disorders.
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Affiliation(s)
- Soha Abdelwahab
- Department of Histology and Cell Biology, Faculty of Medicine, Minia University, Minia, Egypt
| | - Sara Abdel Gawad Elsebay
- Department of Histology and Cell Biology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Manar Fouli Gaber
- Department of Histology and Cell Biology, Faculty of Medicine, Minia University, Minia, Egypt
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31
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Gonzalez-Rodriguez P, Zampese E, Surmeier DJ. Selective neuronal vulnerability in Parkinson's disease. PROGRESS IN BRAIN RESEARCH 2020; 252:61-89. [PMID: 32247375 DOI: 10.1016/bs.pbr.2020.02.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease, disabling millions worldwide. Despite the imperative PD poses, at present, there is no cure or means of slowing progression. This gap is attributable to our incomplete understanding of the factors driving pathogenesis. Research over the past several decades suggests that both cell-autonomous and non-cell autonomous processes contribute to the neuronal dysfunction underlying PD symptoms. The thesis of this review is that an intersection of these processes governs the pattern of pathology in PD. Studies of substantia nigra pars compacta (SNc) dopaminergic neurons, whose loss is responsible for the core motor symptoms of PD, suggest that they have a combination of traits-a long, highly branched axon, autonomous activity, and elevated mitochondrial oxidant stress-that predispose them to non-cell autonomous drivers of pathogenesis, like misfolded forms of alpha-synuclein (α-SYN) and inflammation. The literature surrounding these issues will be briefly summarized, and the translational implications of an intersectional hypothesis of PD pathogenesis discussed.
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Affiliation(s)
| | - Enrico Zampese
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - D James Surmeier
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States.
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32
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Noncanonical Roles of h α-syn (A53T) in the Pathogenesis of Parkinson's Disease: Synaptic Pathology and Neuronal Aging. Neural Plast 2020; 2020:6283754. [PMID: 32273890 PMCID: PMC7115172 DOI: 10.1155/2020/6283754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 01/04/2020] [Accepted: 01/31/2020] [Indexed: 12/26/2022] Open
Abstract
The motor and nonmotor symptoms of PD involve several brain regions. However, whether α-syn pathology originating from the SNc can directly lead to the pathological changes in distant cerebral regions and induce PD-related symptoms remains unclear. Here, AAV9-synapsin-mCherry-human SNCA (A53T) was injected into the unilateral SNc of mice. Motor function and olfactory sensitivity were evaluated. Our results showed that AAV9-synapsin-mCherry-human SNCA was continuously expressed in SNc. The animals showed mild motor and olfactory dysfunction at 7 months after viral injection. The pathology in SNc was characterized by the loss of dopaminergic neurons accompanied by ER stress. In the striatum, hα-syn expression was high, CaMKβ-2 and NR2B expression decreased, and active synapses reduced. In the olfactory bulb, hα-syn expression was high, and aging cells in the mitral layer increased. The results suggested that hα-syn was transported in the striatum and OB along the nerve fibers that originated from the SNc and induced pathological changes in the distant cerebral regions, which contributed to the motor and nonmotor symptoms of PD.
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33
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Mitochondrial Dysfunction Combined with High Calcium Load Leads to Impaired Antioxidant Defense Underlying the Selective Loss of Nigral Dopaminergic Neurons. J Neurosci 2020; 40:1975-1986. [PMID: 32005765 DOI: 10.1523/jneurosci.1345-19.2019] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/15/2019] [Accepted: 11/24/2019] [Indexed: 12/13/2022] Open
Abstract
Mitochondrial dysfunction is critically involved in Parkinson's disease, characterized by loss of dopaminergic neurons (DaNs) in the substantia nigra (SNc), whereas DaNs in the neighboring ventral tegmental area (VTA) are much less affected. In contrast to VTA, SNc DaNs engage calcium channels to generate action potentials, which lead to oxidant stress by yet unknown pathways. To determine the molecular mechanisms linking calcium load with selective cell death in the presence of mitochondrial deficiency, we analyzed the mitochondrial redox state and the mitochondrial membrane potential in mice of both sexes with genetically induced, severe mitochondrial dysfunction in DaNs (MitoPark mice), at the same time expressing a redox-sensitive GFP targeted to the mitochondrial matrix. Despite mitochondrial insufficiency in all DaNs, exclusively SNc neurons showed an oxidized redox-system, i.e., a low reduced/oxidized glutathione (GSH-GSSG) ratio. This was mimicked by cyanide, but not by rotenone or antimycin A, making the involvement of reactive oxygen species rather unlikely. Surprisingly, a high mitochondrial inner membrane potential was maintained in MitoPark SNc DaNs. Antagonizing calcium influx into the cell and into mitochondria, respectively, rescued the disturbed redox ratio and induced further hyperpolarization of the inner mitochondrial membrane. Our data therefore show that the constant calcium load in SNc DaNs is counterbalanced by a high mitochondrial inner membrane potential, even under conditions of severe mitochondrial dysfunction, but triggers a detrimental imbalance in the mitochondrial redox system, which will lead to neuron death. Our findings thus reveal a new mechanism, redox imbalance, which underlies the differential vulnerability of DaNs to mitochondrial defects.SIGNIFICANCE STATEMENT Parkinson's disease is characterized by the preferential degeneration of dopaminergic neurons (DaNs) of the substantia nigra pars compacta (SNc), resulting in the characteristic hypokinesia in patients. Ubiquitous pathological triggers cannot be responsible for the selective neuron loss. Here we show that mitochondrial impairment together with elevated calcium burden destabilize the mitochondrial antioxidant defense only in SNc DaNs, and thus promote the increased vulnerability of this neuron population.
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34
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Verma A, Ravindranath V. Ca V1.3 L-Type Calcium Channels Increase the Vulnerability of Substantia Nigra Dopaminergic Neurons in MPTP Mouse Model of Parkinson's Disease. Front Aging Neurosci 2020; 11:382. [PMID: 32009942 PMCID: PMC6978652 DOI: 10.3389/fnagi.2019.00382] [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: 09/27/2019] [Accepted: 12/30/2019] [Indexed: 12/16/2022] Open
Abstract
Mechanisms underlying the selective vulnerability of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) over those in the ventral tegmental area (VTA) to degeneration in Parkinson’s disease (PD) remain poorly understood. DA neurons of SNpc and VTA are autonomous pacemakers but pacemaking in SNpc but not in VTA is accompanied by calcium influx through L-type calcium channel, CaV1.3 contributing to increased intracellular calcium and hence to cell death. CaV1.342A, an alternatively spliced short variant of CaV1.3 has increased calcium influx. We, therefore studied the role of CaV1.342 (full-length channel) and CaV1.342A in mouse SNpc in PD pathogenesis by quantifying mRNA levels of CaV1.342 and CaV1.342A in SNpc and followed the change in their levels in MPTP induced parkinsonism mouse model. Using in situ hybridization and immunohistochemistry we observed the localization of mRNA of CaV1.342 and CaV1.342A in tyrosine hydroxylase (TH) positive DA neurons. Further, mRNA levels of CaV1.342A were higher in SNpc as compared to the cortex. Upon MPTP treatment, mRNA levels of CaV1.342 and CaV1.342A maintained their levels in SNpc in spite of the loss of ~50% of the DA neurons. This indicates that the expression of CaV1.342 and CaV1.342A is maintained at a robust level during the degenerative process in the parkinsonism model.
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Affiliation(s)
- Aditi Verma
- Centre for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Vijayalakshmi Ravindranath
- Centre for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Bangalore, India.,Centre for Brain Research, Indian Institute of Science, Bangalore, India
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35
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Lieberman OJ, Frier MD, McGuirt AF, Griffey CJ, Rafikian E, Yang M, Yamamoto A, Borgkvist A, Santini E, Sulzer D. Cell-type-specific regulation of neuronal intrinsic excitability by macroautophagy. eLife 2020; 9:e50843. [PMID: 31913125 PMCID: PMC6984822 DOI: 10.7554/elife.50843] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 01/07/2020] [Indexed: 12/28/2022] Open
Abstract
The basal ganglia are a group of subcortical nuclei that contribute to action selection and reinforcement learning. The principal neurons of the striatum, spiny projection neurons of the direct (dSPN) and indirect (iSPN) pathways, maintain low intrinsic excitability, requiring convergent excitatory inputs to fire. Here, we examined the role of autophagy in mouse SPN physiology and animal behavior by generating conditional knockouts of Atg7 in either dSPNs or iSPNs. Loss of autophagy in either SPN population led to changes in motor learning but distinct effects on cellular physiology. dSPNs, but not iSPNs, required autophagy for normal dendritic structure and synaptic input. In contrast, iSPNs, but not dSPNs, were intrinsically hyperexcitable due to reduced function of the inwardly rectifying potassium channel, Kir2. These findings define a novel mechanism by which autophagy regulates neuronal activity: control of intrinsic excitability via the regulation of potassium channel function.
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Affiliation(s)
- Ori J Lieberman
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | - Micah D Frier
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | - Avery F McGuirt
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | - Christopher J Griffey
- Department of NeurologyColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | - Elizabeth Rafikian
- Mouse NeuroBehavior Core, Institute for Genomic MedicineColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | - Mu Yang
- Mouse NeuroBehavior Core, Institute for Genomic MedicineColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | - Ai Yamamoto
- Department of NeurologyColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
| | | | | | - David Sulzer
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
- Department of NeurologyColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
- Department of PharmacologyColumbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
- Division of Molecular TherapeuticsNew York State Psychiatric InstituteNew YorkUnited States
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36
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Lebowitz JJ, Khoshbouei H. Heterogeneity of dopamine release sites in health and degeneration. Neurobiol Dis 2019; 134:104633. [PMID: 31698055 DOI: 10.1016/j.nbd.2019.104633] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/12/2019] [Accepted: 10/02/2019] [Indexed: 02/06/2023] Open
Abstract
Despite comprising only ~ 0.001% of all neurons in the human brain, ventral midbrain dopamine neurons exert a profound influence on human behavior and cognition. As a neuromodulator, dopamine selectively inhibits or enhances synaptic signaling to coordinate neural output for action, attention, and affect. Humans invariably lose brain dopamine during aging, and this can be exacerbated in disease states such as Parkinson's Disease. Further, it is well established in multiple disease states that cell loss is selective for a subset of highly sensitive neurons within the nigrostriatal dopamine tract. Regional differences in dopamine tone are regulated pre-synaptically, with subcircuits of projecting dopamine neurons exhibiting distinct molecular and physiological signatures. Specifically, proteins at dopamine release sites that synthesize and package cytosolic dopamine, modulate its release and reuptake, and alter neuronal excitability show regional differences that provide linkages to the observed sensitivity to neurodegeneration. The aim of this review is to outline the major components of dopamine homeostasis at neurotransmitter release sites and describe the regional differences most relevant to understanding why some, but not all, dopamine neurons exhibit heightened vulnerability to neurodegeneration.
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Affiliation(s)
- Joseph J Lebowitz
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Habibeh Khoshbouei
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32610, USA.
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37
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Li H, Jiang H, Zhang B, Feng J. Modeling Parkinson's Disease Using Patient-specific Induced Pluripotent Stem Cells. JOURNAL OF PARKINSONS DISEASE 2019; 8:479-493. [PMID: 30149462 PMCID: PMC6218140 DOI: 10.3233/jpd-181353] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Parkinson’s disease (PD) is the second most common neurodegenerative disorder. It is characterized by the degeneration of nigral dopaminergic (DA) neurons. While over 90% of cases are idiopathic, without a clear etiology, mutations in many genes have been linked to rare, familial forms of PD. It has been quite challenging to develop effective animal models of PD that capture salient features of PD. The discovery of induced pluripotent stem cells (iPSCs) makes it possible to generate patient-specific DA neurons to study PD. Here, we review the methods for the generation of iPSCs and discuss previous studies using iPSC-derived neurons from monogenic forms of PD. These investigations have revealed several converging pathways that intersect with the unique vulnerabilities of human nigral DA neurons. With the rapid development in stem cell biology, it is possible to generate patient-specific neurons that will be increasingly similar to those in the brain of the patient. Combined with the ability to edit the genome to generate isogenic iPSCs, the generation and analysis of patient-specific midbrain DA neurons will transform PD research by providing a valuable tool for mechanistic study and drug discovery.
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Affiliation(s)
- Hong Li
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA.,Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, USA
| | - Houbo Jiang
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA.,Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, USA
| | - Boyang Zhang
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA.,Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, USA
| | - Jian Feng
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA.,Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, USA
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38
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Soman SK, Bazała M, Keatinge M, Bandmann O, Kuznicki J. Restriction of mitochondrial calcium overload by mcu inactivation renders a neuroprotective effect in zebrafish models of Parkinson's disease. Biol Open 2019; 8:bio044347. [PMID: 31548178 PMCID: PMC6826286 DOI: 10.1242/bio.044347] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 09/13/2019] [Indexed: 12/21/2022] Open
Abstract
The loss of dopaminergic neurons (DA) is a pathological hallmark of sporadic and familial forms of Parkinson's disease (PD). We have previously shown that inhibiting mitochondrial calcium uniporter (mcu) using morpholinos can rescue DA neurons in the PTEN-induced putative kinase 1 (pink1)-/- zebrafish model of PD. In this article, we show results from our studies in mcu knockout zebrafish, which was generated using the CRISPR/Cas9 system. Functional assays confirmed impaired mitochondrial calcium influx in mcu -/- zebrafish. We also used in vivo calcium imaging and fluorescent assays in purified mitochondria to investigate mitochondrial calcium dynamics in a pink1 -/- zebrafish model of PD. Mitochondrial morphology was evaluated in DA neurons and muscle fibers using immunolabeling and transgenic lines, respectively. We observed diminished mitochondrial area in DA neurons of pink1 -/- zebrafish, while deletion of mcu restored mitochondrial area. In contrast, the mitochondrial volume in muscle fibers was not restored after inactivation of mcu in pink1 -/- zebrafish. Mitochondrial calcium overload coupled with depolarization of mitochondrial membrane potential leads to mitochondrial dysfunction in the pink1 -/- zebrafish model of PD. We used in situ hybridization and immunohistochemical labeling of DA neurons to evaluate the effect of mcu deletion on DA neuronal clusters in the ventral telencephalon of zebrafish brain. We show that DA neurons are rescued after deletion of mcu in pink1 -/- and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) zebrafish model of PD. Thus, inactivation of mcu is protective in both genetic and chemical models of PD. Our data reveal that regulating mcu function could be an effective therapeutic target in PD pathology.
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Affiliation(s)
- Smijin K Soman
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Księcia Trojdena 4, 02-109, Warsaw, Poland
| | - Michal Bazała
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Księcia Trojdena 4, 02-109, Warsaw, Poland
| | - Marcus Keatinge
- Medical Research Council Centre for Developmental and Biomedical Genetics, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385a Glossop Road, Sheffield, S10 2HQ, UK
| | - Oliver Bandmann
- Medical Research Council Centre for Developmental and Biomedical Genetics, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385a Glossop Road, Sheffield, S10 2HQ, UK
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Księcia Trojdena 4, 02-109, Warsaw, Poland
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39
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Leandrou E, Emmanouilidou E, Vekrellis K. Voltage-Gated Calcium Channels and α-Synuclein: Implications in Parkinson's Disease. Front Mol Neurosci 2019; 12:237. [PMID: 31649506 PMCID: PMC6794345 DOI: 10.3389/fnmol.2019.00237] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/17/2019] [Indexed: 12/15/2022] Open
Abstract
Alpha-synuclein (α-syn) is biochemically and genetically linked to Parkinson's disease (PD) and other synucleinopathies. It is now widely accepted that α-syn can be released in the extracellular space, even though the mechanism of its release is still unclear. In addition, pathology-related aggregated species of α-syn have been shown to propagate between neurons in synaptically connected areas of the brain thereby assisting the spreading of pathology in healthy neighboring neuronal cells. In neurons, calcium channels are key signaling elements that modulate the release of bioactive molecules (hormones, proteins, and neurotransmitters) through calcium sensing. Such calcium sensing activity is determined by the distinct biophysical and pharmacological properties and the ability of calcium channels to interact with other modulatory proteins. Although the function of extracellular α-syn is currently unknown, previous work suggested the presence of a calcium-dependent mechanism for α-syn secretion both in vitro, in neuronal cells in culture, and also in vivo, in the context of a trans-neuronal network in brain. Mechanisms regulating extracellular α-syn levels may be of particular importance as they could represent novel therapeutic targets. We discuss here how calcium channel activity may contribute to α-syn aggregation and secretion as a pathway to disease progression in synucleinopathies.
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Affiliation(s)
- Emmanouela Leandrou
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, Athens, Greece
| | - Evangelia Emmanouilidou
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, Athens, Greece.,Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Kostas Vekrellis
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, Athens, Greece
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40
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Burbulla LF, Krainc D. The role of dopamine in the pathogenesis of GBA1-linked Parkinson's disease. Neurobiol Dis 2019; 132:104545. [PMID: 31351996 DOI: 10.1016/j.nbd.2019.104545] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 05/21/2019] [Accepted: 07/24/2019] [Indexed: 12/20/2022] Open
Abstract
Our understanding of the molecular mechanisms underlying differential vulnerability of substantia nigra dopamine neurons in Parkinson's disease (PD) remains limited, and previous therapeutic efforts targeting rodent nigral neurons have not been successfully translated to humans. However, recent emergence of induced pluripotent stem cell technology has highlighted some fundamental differences between human and rodent midbrain dopamine neurons that may at least in part explain relative resistance of rodent neurons to degeneration in genetic models of PD. Using GBA1-linked PD as an example, we discuss cellular pathways that may predispose human neurons to degeneration in PD, including mitochondrial oxidant stress, elevated intracellular calcium, altered synaptic vesicle endocytosis, accumulation of oxidized dopamine and neuromelanin. Recent studies have suggested that a combination of mitochondrial oxidant stress and accumulation of oxidized dopamine contribute to dysfunction of nigral neurons in various genetic and sporadic forms of PD. We also briefly summarize the development of targeted therapies for GBA1-associated synucleinopathies and highlight that modulation of wild-type GCase activity serves as an important target for the treatment of genetic and idiopathic forms of PD and dementia with Lewy bodies.
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Affiliation(s)
- Lena F Burbulla
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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41
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Mitochondrial Dysfunction in Parkinson's Disease-Cause or Consequence? BIOLOGY 2019; 8:biology8020038. [PMID: 31083583 PMCID: PMC6627981 DOI: 10.3390/biology8020038] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/25/2019] [Accepted: 02/05/2019] [Indexed: 12/18/2022]
Abstract
James Parkinson first described the motor symptoms of the disease that took his name over 200 years ago. While our knowledge of many of the changes that occur in this condition has increased, it is still unknown what causes this neurodegeneration and why it only affects some individuals with advancing age. Here we review current literature to discuss whether the mitochondrial dysfunction we have detected in Parkinson’s disease is a pathogenic cause of neuronal loss or whether it is itself a consequence of dysfunction in other pathways. We examine research data from cases of idiopathic Parkinson’s with that from model systems and individuals with familial forms of the disease. Furthermore, we include data from healthy aged individuals to highlight that many of the changes described are also present with advancing age, though not normally in the presence of severe neurodegeneration. While a definitive answer to this question may still be just out of reach, it is clear that mitochondrial dysfunction sits prominently at the centre of the disease pathway that leads to catastrophic neuronal loss in those affected by this disease.
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42
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Garretti F, Agalliu D, Lindestam Arlehamn CS, Sette A, Sulzer D. Autoimmunity in Parkinson's Disease: The Role of α-Synuclein-Specific T Cells. Front Immunol 2019; 10:303. [PMID: 30858851 PMCID: PMC6397885 DOI: 10.3389/fimmu.2019.00303] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/06/2019] [Indexed: 12/23/2022] Open
Abstract
Evidence from a variety of studies implicates a role for the adaptive immune system in Parkinson's disease (PD). Similar to multiple sclerosis (MS) patients who display a high number of T cells in the brain attacking oligodendrocytes, PD patients show higher numbers of T cells in the ventral midbrain than healthy, age-matched controls. Mouse models of the disease also show the presence of T cells in the brain. The role of these infiltrating T cells in the propagation of disease is controversial; however, recent studies indicate that they may be autoreactive in nature, recognizing disease-altered self-proteins as foreign antigens. T cells of PD patients can generate an autoimmune response to α-synuclein, a protein that is aggregated in PD. α-Synuclein and other proteins are post-translationally modified in an environment in which protein processing is altered, possibly leading to the generation of neo-epitopes, or self-peptides that have not been identified by the host immune system as non-foreign. Infiltrating T cells may also be responding to such modified proteins. Genome-wide association studies (GWAS) have shown associations of PD with haplotypes of major histocompatibility complex (MHC) class II genes, and a polymorphism in a non-coding region that may increase MHC class II in PD patients. We speculate that the inflammation observed in PD may play both pathogenic and protective roles. Future studies on the adaptive immune system in neurodegenerative disorders may elucidate steps in disease pathogenesis and assist with the development of both biomarkers and treatments.
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Affiliation(s)
- Francesca Garretti
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, United States
| | - Dritan Agalliu
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, United States.,Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
| | | | - Alessandro Sette
- Division of Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, CA, United States.,Department of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - David Sulzer
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States.,Department of Pharmacology, Columbia University Irving Medical Center, New York, NY, United States.,Department of Psychiatry, Columbia University Irving Medical Center, New York, NY, United States
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43
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Switching on Endogenous Metal Binding Proteins in Parkinson's Disease. Cells 2019; 8:cells8020179. [PMID: 30791479 PMCID: PMC6406413 DOI: 10.3390/cells8020179] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 01/26/2019] [Accepted: 02/05/2019] [Indexed: 12/28/2022] Open
Abstract
The formation of cytotoxic intracellular protein aggregates is a pathological signature of multiple neurodegenerative diseases. The principle aggregating protein in Parkinson’s disease (PD) and atypical Parkinson’s diseases is α-synuclein (α-syn), which occurs in neural cytoplasmic inclusions. Several factors have been found to trigger α-syn aggregation, including raised calcium, iron, and copper. Transcriptional inducers have been explored to upregulate expression of endogenous metal-binding proteins as a potential neuroprotective strategy. The vitamin-D analogue, calcipotriol, induced increased expression of the neuronal vitamin D-dependent calcium-binding protein, calbindin-D28k, and this significantly decreased the occurrence of α-syn aggregates in cells with transiently raised intracellular free Ca, thereby increasing viability. More recently, the induction of endogenous expression of the Zn and Cu binding protein, metallothionein, by the glucocorticoid analogue, dexamethasone, gave a specific reduction in Cu-dependent α-syn aggregates. Fe accumulation has long been associated with PD. Intracellularly, Fe is regulated by interactions between the Fe storage protein ferritin and Fe transporters, such as poly(C)-binding protein 1. Analysis of the transcriptional regulation of Fe binding proteins may reveal potential inducers that could modulate Fe homoeostasis in disease. The current review highlights recent studies that suggest that transcriptional inducers may have potential as novel mechanism-based drugs against metal overload in PD.
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44
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Liss B, Striessnig J. The Potential of L-Type Calcium Channels as a Drug Target for Neuroprotective Therapy in Parkinson's Disease. Annu Rev Pharmacol Toxicol 2019; 59:263-289. [PMID: 30625283 DOI: 10.1146/annurev-pharmtox-010818-021214] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The motor symptoms of Parkinson's disease (PD) mainly arise from degeneration of dopamine neurons within the substantia nigra. As no disease-modifying PD therapies are available, and side effects limit long-term benefits of current symptomatic therapies, novel treatment approaches are needed. The ongoing phase III clinical study STEADY-PD is investigating the potential of the dihydropyridine isradipine, an L-type Ca2+ channel (LTCC) blocker, for neuroprotective PD therapy. Here we review the clinical and preclinical rationale for this trial and discuss potential reasons for the ambiguous outcomes of in vivo animal model studies that address PD-protective dihydropyridine effects. We summarize current views about the roles of Cav1.2 and Cav1.3 LTCC isoforms for substantia nigra neuron function, and their high vulnerability to degenerative stressors, and for PD pathophysiology. We discuss different dihydropyridine sensitivities of LTCC isoforms in view of their potential as drug targets for PD neuroprotection, and we conclude by considering how these aspects could guide further drug development.
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Affiliation(s)
- Birgit Liss
- Institut für Angewandte Physiologie, Universität Ulm, 89081 Ulm, Germany;
| | - Jörg Striessnig
- Abteilung Pharmakologie und Toxikologie, Institut für Pharmazie, and Center for Molecular Biosciences Innsbruck, Universität Innsbruck, A-6020 Innsbruck, Austria;
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45
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The Cellular Environment Affects Monomeric α-Synuclein Structure. Trends Biochem Sci 2018; 44:453-466. [PMID: 30527975 DOI: 10.1016/j.tibs.2018.11.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/13/2018] [Accepted: 11/16/2018] [Indexed: 12/19/2022]
Abstract
The presynaptic protein α-synuclein (aSyn) is an 'intrinsically disordered protein' that is highly dynamic in conformation. Transient intramolecular interactions between its charged N and C termini, and between its hydrophobic region and the C terminus, prevent self-association. These interactions inhibit the formation of insoluble inclusions, which are the pathological hallmark of Parkinson's disease and many other synucleinopathies. This review discusses how these intramolecular interactions are influenced by the specific environment aSyn is in. We discuss how charge, pH, calcium, and salt affect the physiological structure of monomeric aSyn, and how they may favour the formation of toxic structures. The more we understand the dynamic conformations of aSyn, the better we can design desperately needed therapeutics to prevent disease progression.
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46
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Mikami Y. [Pathophysiological functions of gas mediators in neurodegeneration]. Nihon Yakurigaku Zasshi 2018; 152:233-239. [PMID: 30393255 DOI: 10.1254/fpj.152.233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Since the discovery of nitric oxide (NO) as gaseous signaling molecule, two other gaseous mediators, carbon monoxide (CO) and hydrogen sulfide (H2S) have been found to be also involved in many physiological and pathophysiological functions. This review will briefly summarize our recent progress in the pathophysiology of NO and H2S. In the photoreceptor cells, the level of intracellular Ca2+ is kept relatively low by H2S. Intraperitoneal injection of H2S donor to mice protected photoreceptor cells from light-induced retinal degeneration caused by oxidative stress and elevation of intracellular Ca2+. Another gaseous mediator NO induces Ca2+ release from the endoplasmic reticulum via S-nitrosylated type 1 ryanodine receptor (RyR1) Ca2+ release channel. NO-induced Ca2+ release (NICR) was abolished in primary cultured neurons from the knock-in mice, in which the S-nitrosylation site Cys-3636 of RyR1 was replaced by Ala (Ryr1C3636A). The neurons in hippocampal CA3 region of Ryr1C3636A mice were protected against seizure-induced neuronal cell death. The result indicates that NICR is critical for status epilepticus-induced neurodegeneration. The developments in the pathophysiology of gaseous mediators in the central nervous system will provide a better pharmacological advances for the treatment of neurodegenerative diseases.
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47
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Teplov IY, Tuleukhanov ST, Zinchenko VP. Regulation of Action Potential Frequency and Amplitude by T-type Ca2+ Channel During Spontaneous Synchronous Activity of Hippocampal Neurons. Biophysics (Nagoya-shi) 2018. [DOI: 10.1134/s0006350918040206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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48
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Verma M, Wills Z, Chu CT. Excitatory Dendritic Mitochondrial Calcium Toxicity: Implications for Parkinson's and Other Neurodegenerative Diseases. Front Neurosci 2018; 12:523. [PMID: 30116173 PMCID: PMC6083050 DOI: 10.3389/fnins.2018.00523] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 07/12/2018] [Indexed: 12/22/2022] Open
Abstract
Dysregulation of calcium homeostasis has been linked to multiple neurological diseases. In addition to excitotoxic neuronal cell death observed following stroke, a growing number of studies implicate excess excitatory neuronal activity in chronic neurodegenerative diseases. Mitochondria function to rapidly sequester large influxes of cytosolic calcium through the activity of the mitochondrial calcium uniporter (MCU) complex, followed by more gradual release via calcium antiporters, such as NCLX. Increased cytosolic calcium levels almost invariably result in increased mitochondrial calcium uptake. While this response may augment mitochondrial respiration, limiting classic excitotoxic injury in the short term, recent studies employing live calcium imaging and molecular manipulation of calcium transporter activities suggest that mitochondrial calcium overload plays a key role in Parkinson’s disease (PD), Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), and related dementias [PD with dementia (PDD), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD)]. Herein, we review the literature on increased excitatory input, mitochondrial calcium dysregulation, and the transcriptional or post-translational regulation of mitochondrial calcium transport proteins, with an emphasis on the PD-linked kinases LRRK2 and PINK1. The impact on pathological dendrite remodeling and neuroprotective effects of manipulating MCU, NCLX, and LETM1 are reviewed. We propose that shortening and simplification of the dendritic arbor observed in neurodegenerative diseases occur through a process of excitatory mitochondrial toxicity (EMT), which triggers mitophagy and perisynaptic mitochondrial depletion, mechanisms that are distinct from classic excitotoxicity.
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Affiliation(s)
- Manish Verma
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Zachary Wills
- Department of Neurobiology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Charleen T Chu
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Pittsburgh Institute for Neurodegenerative Diseases, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Protein Conformational Diseases, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Neuroscience, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
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49
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Vicario M, Cieri D, Brini M, Calì T. The Close Encounter Between Alpha-Synuclein and Mitochondria. Front Neurosci 2018; 12:388. [PMID: 29930495 PMCID: PMC5999749 DOI: 10.3389/fnins.2018.00388] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/22/2018] [Indexed: 01/02/2023] Open
Abstract
The presynaptic protein alpha-synuclein (α-syn) is unequivocally linked to the development of Parkinson’s disease (PD). Not only it is the major component of amyloid fibrils found in Lewy bodies but mutations and duplication/triplication in its gene are responsible for the onset of familial autosomal dominant forms of PD. Nevertheless, the precise mechanisms leading to neuronal degeneration are not fully understood. Several lines of evidence suggest that impaired autophagy clearance and mitochondrial dysfunctions such as bioenergetics and calcium handling defects and alteration in mitochondrial morphology might play a pivotal role in the etiology and progression of PD, and indicate the intriguing possibility that α-syn could be involved in the control of mitochondrial function both in physiological and pathological conditions. In favor of this, it has been shown that a fraction of cellular α-syn can selectively localize to mitochondrial sub-compartments upon specific stimuli, highlighting possible novel routes for α-syn action. A plethora of mitochondrial processes, including cytochrome c release, calcium homeostasis, control of mitochondrial membrane potential and ATP production, is directly influenced by α-syn. Eventually, α-syn localization within mitochondria may also account for its aggregation state, making the α-syn/mitochondria intimate relationship a potential key for the understanding of PD pathogenesis. Here, we will deeply survey the recent literature in the field by focusing our attention on the processes directly controlled by α-syn within mitochondrial sub-compartments and its potential partners providing possible hints for future therapeutic targets.
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Affiliation(s)
- Mattia Vicario
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Domenico Cieri
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Marisa Brini
- Department of Biology, University of Padova, Padova, Italy
| | - Tito Calì
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Padova Neuroscience Center, University of Padova, Padova, Italy
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50
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Jayaraj ND, Bhattacharyya BJ, Belmadani AA, Ren D, Rathwell CA, Hackelberg S, Hopkins BE, Gupta HR, Miller RJ, Menichella DM. Reducing CXCR4-mediated nociceptor hyperexcitability reverses painful diabetic neuropathy. J Clin Invest 2018. [PMID: 29533926 DOI: 10.1172/jci92117] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Painful diabetic neuropathy (PDN) is an intractable complication of diabetes that affects 25% of patients. PDN is characterized by neuropathic pain and small-fiber degeneration, accompanied by dorsal root ganglion (DRG) nociceptor hyperexcitability and loss of their axons within the skin. The molecular mechanisms underlying DRG nociceptor hyperexcitability and small-fiber degeneration in PDN are unknown. We hypothesize that chemokine CXCL12/CXCR4 signaling is central to this mechanism, as we have shown that CXCL12/CXCR4 signaling is necessary for the development of mechanical allodynia, a pain hypersensitivity behavior common in PDN. Focusing on DRG neurons expressing the sodium channel Nav1.8, we applied transgenic, electrophysiological, imaging, and chemogenetic techniques to test this hypothesis. In the high-fat diet mouse model of PDN, we were able to prevent and reverse mechanical allodynia and small-fiber degeneration by limiting CXCR4 signaling or neuronal excitability. This study reveals that excitatory CXCR4/CXCL12 signaling in Nav1.8-positive DRG neurons plays a critical role in the pathogenesis of mechanical allodynia and small-fiber degeneration in a mouse model of PDN. Hence, we propose that targeting CXCR4-mediated DRG nociceptor hyperexcitability is a promising therapeutic approach for disease-modifying treatments for this currently intractable and widespread affliction.
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Affiliation(s)
| | | | - Abdelhak A Belmadani
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Dongjun Ren
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Craig A Rathwell
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | | | - Brittany E Hopkins
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Herschel R Gupta
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Richard J Miller
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Daniela M Menichella
- Department of Neurology and.,Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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