1
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Rabanal-Ruiz Y, Pedrero-Prieto CM, Sanchez-Rodriguez L, Flores-Cuadrado A, Saiz-Sanchez D, Frontinan-Rubio J, Ubeda-Banon I, Duran Prado M, Martinez-Marcos A, Peinado JR. Differential accumulation of human β-amyloid and tau from enriched extracts in neuronal and endothelial cells. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167204. [PMID: 38679217 DOI: 10.1016/j.bbadis.2024.167204] [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: 10/30/2023] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 05/01/2024]
Abstract
While Aβ and Tau cellular distribution has been largely studied, the comparative internalization and subcellular accumulation of Tau and Aβ isolated from human brain extracts in endothelial and neuronal cells has not yet been unveiled. We have previously demonstrated that controlled enrichment of Aβ from human brain extracts constitutes a valuable tool to monitor cellular internalization in vitro and in vivo. Herein, we establish an alternative method to strongly enrich Aβ and Tau aggregates from human AD brains, which has allowed us to study and compare the cellular internalization, distribution and toxicity of both proteins within brain barrier endothelial (bEnd.3) and neuronal (Neuro2A) cells. Our findings demonstrate the suitability of human enriched brain extracts to monitor the intracellular distribution of human Aβ and Tau, which, once internalized, show dissimilar sorting to different organelles within the cell and differential toxicity, exhibiting higher toxic effects on neuronal cells than on endothelial cells. While tau is strongly concentrated preferentially in mitochondria, Aβ is distributed predominantly within the endolysosomal system in endothelial cells, whereas the endoplasmic reticulum was its preferential location in neurons. Altogether, our findings display a picture of the interactions that human Aβ and Tau might establish in these cells.
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Affiliation(s)
- Y Rabanal-Ruiz
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - C M Pedrero-Prieto
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - L Sanchez-Rodriguez
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - A Flores-Cuadrado
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - D Saiz-Sanchez
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - J Frontinan-Rubio
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - I Ubeda-Banon
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - M Duran Prado
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - A Martinez-Marcos
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain.
| | - Juan R Peinado
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain.
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2
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Baev AY, Vinokurov AY, Potapova EV, Dunaev AV, Angelova PR, Abramov AY. Mitochondrial Permeability Transition, Cell Death and Neurodegeneration. Cells 2024; 13:648. [PMID: 38607087 PMCID: PMC11011324 DOI: 10.3390/cells13070648] [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: 03/10/2024] [Revised: 03/27/2024] [Accepted: 04/06/2024] [Indexed: 04/13/2024] Open
Abstract
Neurodegenerative diseases are chronic conditions occurring when neurons die in specific brain regions that lead to loss of movement or cognitive functions. Despite the progress in understanding the mechanisms of this pathology, currently no cure exists to treat these types of diseases: for some of them the only help is alleviating the associated symptoms. Mitochondrial dysfunction has been shown to be involved in the pathogenesis of most the neurodegenerative disorders. The fast and transient permeability of mitochondria (the mitochondrial permeability transition, mPT) has been shown to be an initial step in the mechanism of apoptotic and necrotic cell death, which acts as a regulator of tissue regeneration for postmitotic neurons as it leads to the irreparable loss of cells and cell function. In this study, we review the role of the mitochondrial permeability transition in neuronal death in major neurodegenerative diseases, covering the inductors of mPTP opening in neurons, including the major ones-free radicals and calcium-and we discuss perspectives and difficulties in the development of a neuroprotective strategy based on the inhibition of mPTP in neurodegenerative disorders.
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Affiliation(s)
- Artyom Y. Baev
- Laboratory of Experimental Biophysics, Centre for Advanced Technologies, Tashkent 100174, Uzbekistan;
- Department of Biophysics, Faculty of Biology, National University of Uzbekistan, Tashkent 100174, Uzbekistan
| | - Andrey Y. Vinokurov
- Cell Physiology and Pathology Laboratory, Orel State University, Orel 302026, Russia; (A.Y.V.); (E.V.P.); (A.V.D.)
| | - Elena V. Potapova
- Cell Physiology and Pathology Laboratory, Orel State University, Orel 302026, Russia; (A.Y.V.); (E.V.P.); (A.V.D.)
| | - Andrey V. Dunaev
- Cell Physiology and Pathology Laboratory, Orel State University, Orel 302026, Russia; (A.Y.V.); (E.V.P.); (A.V.D.)
| | - Plamena R. Angelova
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK;
| | - Andrey Y. Abramov
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK;
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3
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Dagar S, Sharma M, Tsaprailis G, Tapia CS, Crynen G, Joshi PS, Shahani N, Subramaniam S. Ribosome Profiling and Mass Spectrometry Reveal Widespread Mitochondrial Translation Defects in a Striatal Cell Model of Huntington Disease. Mol Cell Proteomics 2024; 23:100746. [PMID: 38447791 PMCID: PMC11040134 DOI: 10.1016/j.mcpro.2024.100746] [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: 09/21/2023] [Revised: 02/22/2024] [Accepted: 03/03/2024] [Indexed: 03/08/2024] Open
Abstract
Huntington disease (HD) is caused by an expanded polyglutamine mutation in huntingtin (mHTT) that promotes prominent atrophy in the striatum and subsequent psychiatric, cognitive deficits, and choreiform movements. Multiple lines of evidence point to an association between HD and aberrant striatal mitochondrial functions; however, the present knowledge about whether (or how) mitochondrial mRNA translation is differentially regulated in HD remains unclear. We found that protein synthesis is diminished in HD mitochondria compared to healthy control striatal cell models. We utilized ribosome profiling (Ribo-Seq) to analyze detailed snapshots of ribosome occupancy of the mitochondrial mRNA transcripts in control and HD striatal cell models. The Ribo-Seq data revealed almost unaltered ribosome occupancy on the nuclear-encoded mitochondrial transcripts involved in oxidative phosphorylation (SDHA, Ndufv1, Timm23, Tomm5, Mrps22) in HD cells. By contrast, ribosome occupancy was dramatically increased for mitochondrially encoded oxidative phosphorylation mRNAs (mt-Nd1, mt-Nd2, mt-Nd4, mt-Nd4l, mt-Nd5, mt-Nd6, mt-Co1, mt-Cytb, and mt-ATP8). We also applied tandem mass tag-based mass spectrometry identification of mitochondrial proteins to derive correlations between ribosome occupancy and actual mature mitochondrial protein products. We found many mitochondrial transcripts with comparable or higher ribosome occupancy, but diminished mitochondrial protein products, in HD. Thus, our study provides the first evidence of a widespread dichotomous effect on ribosome occupancy and protein abundance of mitochondria-related genes in HD.
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Affiliation(s)
- Sunayana Dagar
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - Manish Sharma
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - George Tsaprailis
- Proteomics Core, The Wertheim UF Scripps Institute, Jupiter, Florida, USA
| | | | - Gogce Crynen
- Bioinformatics and Statistics Core, The Wertheim UF Scripps Institute, Jupiter, Florida, USA
| | - Preksha Sandipkumar Joshi
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - Neelam Shahani
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - Srinivasa Subramaniam
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA; The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, California, USA; Norman Fixel Institute for Neurological Diseases, Gainesville, Florida, USA.
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4
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Fuentes JM, Morcillo P. The Role of Cardiolipin in Mitochondrial Function and Neurodegenerative Diseases. Cells 2024; 13:609. [PMID: 38607048 PMCID: PMC11012098 DOI: 10.3390/cells13070609] [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: 03/28/2024] [Accepted: 03/29/2024] [Indexed: 04/13/2024] Open
Abstract
Cardiolipin (CL) is a mitochondria-exclusive phospholipid synthesized in the inner mitochondrial membrane. CL plays a key role in mitochondrial membranes, impacting a plethora of functions this organelle performs. Consequently, it is conceivable that abnormalities in the CL content, composition, and level of oxidation may negatively impact mitochondrial function and dynamics, with important implications in a variety of diseases. This review concentrates on papers published in recent years, combined with basic and underexplored research in CL. We capture new findings on its biological functions in the mitochondria, as well as its association with neurodegenerative diseases such as Alzheimer's disease or Parkinson's disease. Lastly, we explore the potential applications of CL as a biomarker and pharmacological target to mitigate mitochondrial dysfunction.
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Affiliation(s)
- José M. Fuentes
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, 10003 Cáceres, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, Instituto de Salud Carlos III (CIBER-CIBERNED-ISCIII), 28029 Madrid, Spain
- Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE), 10003 Cáceres, Spain
| | - Patricia Morcillo
- Departmentof Neurology, Columbia University, New York, NY 10032, USA
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5
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Eisenbaum M, Pearson A, Ortiz C, Mullan M, Crawford F, Ojo J, Bachmeier C. ApoE4 expression disrupts tau uptake, trafficking, and clearance in astrocytes. Glia 2024; 72:184-205. [PMID: 37668005 DOI: 10.1002/glia.24469] [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: 02/03/2023] [Revised: 08/07/2023] [Accepted: 08/26/2023] [Indexed: 09/06/2023]
Abstract
Tauopathies are a collection of neurodegenerative diseases characterized by the accumulation of pathogenic aggregates of the microtubule-associated protein tau. Despite the prevalence and diversity of tau astrogliopathy in tauopathies, the interactions between astrocytes and tau in the brain, and the influence of neurodegenerative genetic risk factors like the apolipoprotein E4 (apoE4) isoform, are largely unknown. Here, we leveraged primary and immortalized astrocytes expressing humanized apoE isoforms to characterize the mechanisms by which astrocytes interact with and eliminate extracellular tau, and the influence of apoE genotype on these processes. Our work indicates that astrocytes rapidly internalize, process, and release tau via an exosomal secretory mechanism under physiological conditions. However, we found that apoE4 disrupted these processes in comparison to apoE3, resulting in an astrocytic phenotype prone to intracellular tau accumulation. Furthermore, exposure to repetitive mild traumatic brain injuries exacerbated the apoE4-induced impairments in tau processing and elimination by astrocytes in apoE4 targeted-replacement mice. The diminished ability of apoE4 astrocytes to eliminate extracellular tau can lead to an accumulation of pathogenic tau, which induces mitochondrial dysfunction, as demonstrated by our studies. In total, our findings suggest that the apoE4 isoform lowers the threshold of astrocytic resilience to pathogenic tau, rendering them susceptible to bioenergetic deficits in the early stages of neurodegenerative diseases such as traumatic brain injury, potentially contributing to neurological decline.
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Affiliation(s)
| | | | | | | | - Fiona Crawford
- The Roskamp Institute, Sarasota, Florida, USA
- James A. Haley Veterans' Hospital, Tampa, Florida, USA
| | - Joseph Ojo
- The Roskamp Institute, Sarasota, Florida, USA
| | - Corbin Bachmeier
- The Roskamp Institute, Sarasota, Florida, USA
- Bay Pines VA Healthcare System, Bay Pines, Florida, USA
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6
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Du F, Yu Q, Swerdlow RH, Waites CL. Glucocorticoid-driven mitochondrial damage stimulates Tau pathology. Brain 2023; 146:4378-4394. [PMID: 37070763 PMCID: PMC10545530 DOI: 10.1093/brain/awad127] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/10/2023] [Accepted: 03/28/2023] [Indexed: 04/19/2023] Open
Abstract
Prolonged exposure to glucocorticoids, the main stress hormones, damages the brain and is a risk factor for depression and Alzheimer's disease. Two major drivers of glucocorticoid-related neurotoxicity are mitochondrial dysfunction and Tau pathology; however, the molecular/cellular mechanisms precipitating these events, and their causal relationship, remain unclear. Using cultured murine hippocampal neurons and 4-5-month-old mice treated with the synthetic glucocorticoid dexamethasone, we investigate the mechanisms underlying glucocorticoid-induced mitochondrial damage and Tau pathology. We find that glucocorticoids stimulate opening of the mitochondrial permeability transition pore via transcriptional upregulation of its activating component, cyclophilin D. Inhibition of cyclophilin D is protective against glucocorticoid-induced mitochondrial damage as well as Tau phosphorylation and oligomerization in cultured neurons. We further identify the mitochondrially-targeted compound mito-apocynin as an inhibitor of glucocorticoid-induced permeability transition pore opening, and show that this compound protects against mitochondrial dysfunction, Tau pathology, synaptic loss, and behavioural deficits induced by glucocorticoids in vivo. Finally, we demonstrate that mito-apocynin and the glucocorticoid receptor antagonist mifepristone rescue Tau pathology in cytoplasmic hybrid cells, an ex vivo Alzheimer's disease model wherein endogenous mitochondria are replaced with mitochondria from Alzheimer's subjects. These findings show that mitochondrial permeability transition pore opening is a precipitating factor in glucocorticoid-induced mitochondrial dysfunction, and that this event stimulates Tau pathogenesis. Our data also link glucocorticoids to mitochondrial dysfunction and Tau pathology in the context of Alzheimer's disease and suggest that mitochondria are promising therapeutic targets for mitigating stress- and Tau-related brain damage.
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Affiliation(s)
- Fang Du
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer’s Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Qing Yu
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer’s Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Russell H Swerdlow
- University of Kansas Alzheimer’s Disease Center, University of Kansas School of Medicine, Landon Center on Aging, Kansas City, KS 66103, USA
| | - Clarissa L Waites
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer’s Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Neuroscience, Columbia University, New York, NY 10032, USA
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7
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Jang S, Javadov S. Unraveling the mechanisms of cardiolipin function: The role of oxidative polymerization of unsaturated acyl chains. Redox Biol 2023; 64:102774. [PMID: 37300954 PMCID: PMC10363451 DOI: 10.1016/j.redox.2023.102774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/26/2023] [Accepted: 06/03/2023] [Indexed: 06/12/2023] Open
Abstract
Cardiolipin is a unique phospholipid of the inner mitochondrial membrane (IMM) as well as in bacteria. It performs several vital functions such as resisting osmotic rupture and stabilizing the supramolecular structure of large membrane proteins, like ATP synthases and respirasomes. The process of cardiolipin biosynthesis results in the production of immature cardiolipin. A subsequent step is required for its maturation when its acyl groups are replaced with unsaturated acyl chains, primarily linoleic acid. Linoleic acid is the major fatty acid of cardiolipin across all organs and tissues, except for the brain. Linoleic acid is not synthesized by mammalian cells. It has the unique ability to undergo oxidative polymerization at a moderately accelerated rate compared to other unsaturated fatty acids. This property can enable cardiolipin to form covalently bonded net-like structures essential for maintaining the complex geometry of the IMM and gluing the quaternary structure of large IMM protein complexes. Unlike triglycerides, phospholipids possess only two covalently linked acyl chains, which constrain their capacity to develop robust and complicated structures through oxidative polymerization of unsaturated acyl chains. Cardiolipin, on the other hand, has four fatty acids at its disposal to form covalently bonded polymer structures. Despite its significance, the oxidative polymerization of cardiolipin has been overlooked due to the negative perception surrounding biological oxidation and methodological difficulties. Here, we discuss an intriguing hypothesis that oxidative polymerization of cardiolipin is essential for the structure and function of cardiolipin in the IMM in physiological conditions. In addition, we highlight current challenges associated with the identification and characterization of oxidative polymerization of cardiolipin in vivo. Altogether, the study provides a better understanding of the structural and functional role of cardiolipin in mitochondria.
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Affiliation(s)
- Sehwan Jang
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, PR 00936-5067, USA
| | - Sabzali Javadov
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, PR 00936-5067, USA.
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8
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Gautam M, Genç B, Helmold B, Ahrens A, Kuka J, Makrecka-Kuka M, Günay A, Koçak N, Aguilar-Wickings IR, Keefe D, Zheng G, Swaminathan S, Redmon M, Zariwala HA, Özdinler PH. SBT-272 improves TDP-43 pathology in ALS upper motor neurons by modulating mitochondrial integrity, motility, and function. Neurobiol Dis 2023; 178:106022. [PMID: 36716828 DOI: 10.1016/j.nbd.2023.106022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 01/09/2023] [Accepted: 01/25/2023] [Indexed: 01/28/2023] Open
Abstract
Mitochondrial defects are one of the common underlying causes of neuronal vulnerability in neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), and TDP-43 pathology is the most commonly observed proteinopathy. Disrupted inner mitochondrial membrane (IMM) reported in the upper motor neurons (UMNs) of ALS patients with TDP-43 pathology is recapitulated in the UMNs of well-characterized hTDP-43 mouse model of ALS. The construct validity, such as shared and common cellular pathology in mice and human, offers a unique opportunity to test treatment strategies that may translate to patients. SBT-272 is a well-tolerated brain-penetrant small molecule that stabilizes cardiolipin, a phospholipid found in IMM, thereby restoring mitochondrial structure and respiratory function. We investigated whether SBT-272 can improve IMM structure and health in UMNs diseased with TDP-43 pathology in our well-characterized UMN reporter line for ALS. We found that SBT-272 significantly improved mitochondrial structural integrity and restored mitochondrial motility and function. This led to improved health of diseased UMNs in vitro. In comparison to edaravone and AMX0035, SBT-272 appeared more effective in restoring health of diseased UMNs. Chronic treatment of SBT-272 for sixty days starting at an early symptomatic stage of the disease in vivo led to a significant reduction in astrogliosis, microgliosis, and TDP-43 pathology in the ALS motor cortex. Our results underscore the therapeutic potential of SBT-272, especially within the context of TDP-43 pathology and mitochondrial dysfunction.
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Affiliation(s)
- Mukesh Gautam
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Barış Genç
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Benjamin Helmold
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Angela Ahrens
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Janis Kuka
- Latvian Institute of Organic Synthesis (LIOS), Aizkraukles Street 21, LV-2006 Riga, Latvia
| | - Marina Makrecka-Kuka
- Latvian Institute of Organic Synthesis (LIOS), Aizkraukles Street 21, LV-2006 Riga, Latvia
| | - Aksu Günay
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Nuran Koçak
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Izaak R Aguilar-Wickings
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Dennis Keefe
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - Guozhu Zheng
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - Suchitra Swaminathan
- Division of Rheumatology, Department of Medicine, Feinberg School of Medicine, Northwestern University, 420 E Superior St, Chicago, IL 60611, USA.; Robert H. Lurie Comprehensive Cancer Research Center, Feinberg School of Medicine, Northwestern University, 675 N St Clair Fl 21 Ste 100, Chicago, IL 60611, USA
| | - Martin Redmon
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - Hatim A Zariwala
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - P Hande Özdinler
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA; Robert H. Lurie Comprehensive Cancer Research Center, Feinberg School of Medicine, Northwestern University, 675 N St Clair Fl 21 Ste 100, Chicago, IL 60611, USA; Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Northwestern University, 2205 Tech Dr, Evanston, IL 60208, USA..
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9
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Sohrabi T, Mirzaei-Behbahani B, Zadali R, Pirhaghi M, Morozova-Roche LA, Meratan AA. Common Mechanisms Underlying α-Synuclein-Induced Mitochondrial Dysfunction in Parkinson's Disease. J Mol Biol 2023:167992. [PMID: 36736886 DOI: 10.1016/j.jmb.2023.167992] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/19/2023] [Accepted: 01/24/2023] [Indexed: 02/05/2023]
Abstract
Parkinson's disease (PD) is the most common neurological movement disorder characterized by the selective and irreversible loss of dopaminergic neurons in substantia nigra pars compacta resulting in dopamine deficiency in the striatum. While most cases are sporadic or environmental, about 10% of patients have a positive family history with a genetic cause. The misfolding and aggregation of α-synuclein (α-syn) as a casual factor in the pathogenesis of PD has been supported by a great deal of literature. Extensive studies of mechanisms underpinning degeneration of the dopaminergic neurons induced by α-syn dysfunction suggest a complex process that involves multiple pathways, including mitochondrial dysfunction and increased oxidative stress, impaired calcium homeostasis through membrane permeabilization, synaptic dysfunction, impairment of quality control systems, disruption of microtubule dynamics and axonal transport, endoplasmic reticulum/Golgi dysfunction, nucleus malfunction, and microglia activation leading to neuroinflammation. Among them mitochondrial dysfunction has been considered as the most primary target of α-syn-induced toxicity, leading to neuronal cell death in both sporadic and familial forms of PD. Despite reviewing many aspects of PD pathogenesis related to mitochondrial dysfunction, a systemic study on how α-syn malfunction/aggregation damages mitochondrial functionality and leads to neurodegeneration is missing in the literature. In this review, we give a detailed molecular overview of the proposed mechanisms by which α-syn, directly or indirectly, contributes to mitochondrial dysfunction. This may provide valuable insights for development of new therapeutic approaches in relation to PD. Antioxidant-based therapy as a potential strategy to protect mitochondria against oxidative damage, its challenges, and recent developments in the field are discussed.
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Affiliation(s)
- Tahereh Sohrabi
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Behnaz Mirzaei-Behbahani
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Ramin Zadali
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Mitra Pirhaghi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | | | - Ali Akbar Meratan
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.
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10
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Fišar Z. Linking the Amyloid, Tau, and Mitochondrial Hypotheses of Alzheimer's Disease and Identifying Promising Drug Targets. Biomolecules 2022; 12:1676. [PMID: 36421690 PMCID: PMC9687482 DOI: 10.3390/biom12111676] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 10/23/2022] [Accepted: 11/09/2022] [Indexed: 08/27/2023] Open
Abstract
Damage or loss of brain cells and impaired neurochemistry, neurogenesis, and synaptic and nonsynaptic plasticity of the brain lead to dementia in neurodegenerative diseases, such as Alzheimer's disease (AD). Injury to synapses and neurons and accumulation of extracellular amyloid plaques and intracellular neurofibrillary tangles are considered the main morphological and neuropathological features of AD. Age, genetic and epigenetic factors, environmental stressors, and lifestyle contribute to the risk of AD onset and progression. These risk factors are associated with structural and functional changes in the brain, leading to cognitive decline. Biomarkers of AD reflect or cause specific changes in brain function, especially changes in pathways associated with neurotransmission, neuroinflammation, bioenergetics, apoptosis, and oxidative and nitrosative stress. Even in the initial stages, AD is associated with Aβ neurotoxicity, mitochondrial dysfunction, and tau neurotoxicity. The integrative amyloid-tau-mitochondrial hypothesis assumes that the primary cause of AD is the neurotoxicity of Aβ oligomers and tau oligomers, mitochondrial dysfunction, and their mutual synergy. For the development of new efficient AD drugs, targeting the elimination of neurotoxicity, mutual potentiation of effects, and unwanted protein interactions of risk factors and biomarkers (mainly Aβ oligomers, tau oligomers, and mitochondrial dysfunction) in the early stage of the disease seems promising.
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Affiliation(s)
- Zdeněk Fišar
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague, Czech Republic
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11
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Forloni G, La Vitola P, Balducci C. Oligomeropathies, inflammation and prion protein binding. Front Neurosci 2022; 16:822420. [PMID: 36081661 PMCID: PMC9445368 DOI: 10.3389/fnins.2022.822420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 07/28/2022] [Indexed: 11/13/2022] Open
Abstract
The central role of oligomers, small soluble aggregates of misfolded proteins, in the pathogenesis of neurodegenerative disorders is recognized in numerous experimental conditions and is compatible with clinical evidence. To underline this concept, some years ago we coined the term oligomeropathies to define the common mechanism of action of protein misfolding diseases like Alzheimer, Parkinson or prion diseases. Using simple experimental conditions, with direct application of synthetic β amyloid or α-synuclein oligomers intraventricularly at micromolar concentrations, we could detect differences and similarities in the biological consequences. The two oligomer species affected cognitive behavior, neuronal dysfunction and cerebral inflammatory reactions with distinct mechanisms. In these experimental conditions the proposed mediatory role of cellular prion protein in oligomer activities was not confirmed. Together with oligomers, inflammation at different levels can be important early in neurodegenerative disorders; both β amyloid and α-synuclein oligomers induce inflammation and its control strongly affects neuronal dysfunction. This review summarizes our studies with β-amyloid or α-synuclein oligomers, also considering the potential curative role of doxycycline, a well-known antibiotic with anti-amyloidogenic and anti-inflammatory activities. These actions are analyzed in terms of the therapeutic prospects.
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12
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Epremyan KK, Goleva TN, Zvyagilskaya RA. Effect of Tau Protein on Mitochondrial Functions. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:689-701. [PMID: 36171651 DOI: 10.1134/s0006297922080028] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 06/16/2023]
Abstract
Alzheimer's disease is the most common age-related progressive neurodegenerative disorder of brain cortex and hippocampus leading to cognitive impairment. Accumulation of extracellular amyloid plaques and intraneuronal neurofibrillary tangles are believed to be the main hallmarks of the disease. Origin of Alzheimer's disease is not totally clear, multiple initiator factors are likely to exist. Intracellular impacts of Alzheimer's disease include mitochondrial dysfunction, oxidative stress, ER-stress, disruption of autophagy, severe metabolic challenges leading to massive neuronal apoptosis. Mitochondria are the key players in all these processes. This formed the basis for the so-called mitochondrial cascade hypothesis. This review provides current data on the molecular mechanisms of the development of Alzheimer's disease associated with mitochondria. Special attention was paid to the interaction between Tau protein and mitochondria, as well as to the promising therapeutic approaches aimed at preventing development of neurodegeneration.
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Affiliation(s)
- Khoren K Epremyan
- Bach Institute of Biochemistry, Federal Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Tatyana N Goleva
- Bach Institute of Biochemistry, Federal Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071, Russia
| | - Renata A Zvyagilskaya
- Bach Institute of Biochemistry, Federal Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071, Russia
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13
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Levin J, Sing N, Melbourne S, Morgan A, Mariner C, Spillantini MG, Wegrzynowicz M, Dalley JW, Langer S, Ryazanov S, Leonov A, Griesinger C, Schmidt F, Weckbecker D, Prager K, Matthias T, Giese A. Safety, tolerability and pharmacokinetics of the oligomer modulator anle138b with exposure levels sufficient for therapeutic efficacy in a murine Parkinson model: A randomised, double-blind, placebo-controlled phase 1a trial. EBioMedicine 2022; 80:104021. [PMID: 35500536 PMCID: PMC9065877 DOI: 10.1016/j.ebiom.2022.104021] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 04/08/2022] [Accepted: 04/08/2022] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Synucleinopathies such as Parkinson ́s disease (PD), Dementia with Lewy bodies (DLB) and Multiple System Atrophy (MSA) are characterized by deposition of misfolded and aggregated α-synuclein. Small aggregates (oligomers) of α-synuclein have been shown to be the most relevant neurotoxic species and are targeted by anle138b, an orally bioavailable small molecule compound which shows strong disease-modifying effects in animal models of synucleinopathies. METHODS Anle138b was studied in a single-centre, double-blind, randomised, placebo-controlled single ascending dose (SAD) and multiple ascending dose (MAD) study in healthy subjects. Eligible participants were randomly assigned (1:1 for sentinel subjects and 1:5 for main group) to placebo or anle138b (dose range 50 mg to 300 mg per day), respectively. In addition, the effect of food on the pharmakokinetics of anle138b in healthy subjects was examined in doses of 150 mg per day. Participants were randomized to treatment sequence (fed→fasted) or (fasted→fed). Treatment was administered orally in hard gelatine capsules containing either 10 mg or 30 mg of anle138b or excipient only. The primary endpoints were safety and tolerability, the secondary endpoint was pharmakokinetics. Data from all randomized individuals were evaluated. CLINICALTRIALS gov-identifier: NCT04208152. EudraCT-number: 2019-004218-33. FINDINGS Between December 17th, 2019 and June 27th, 2020 196 healthy volunteers were screened and 68 participants were enrolled. Of these, all completed the study per protocol. There were no major protocol deviations. Adverse events in this healthy volunteer trial were mostly mild and all fully recovered or resolved prior to discharge. From baseline to completion of the trial no medically significant individual changes were observed in any system organ class. Already at multiple doses of 200 mg, exposure levels above the fully effective exposure in the MI2 mouse Parkinson model were observed. INTERPRETATION The favourable safety and PK profile of anle138b in doses resulting in exposures above the fully effective plasma level in a mouse Parkinson model warrant further clinical trials in patients with synucleinopathies. FUNDING This study was funded by MODAG GmbH and by the Michael J. Fox foundation for Parkinson's Research.
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Affiliation(s)
- Johannes Levin
- MODAG GmbH, Wendelsheim, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.; Department of Neurology, Ludwig-Maximilians-University Munich, Germany.
| | - Nand Sing
- Quotient Sciences, Mere Way, Ruddington Fields, Ruddington, Nottingham NG11 6JS, UK
| | - Sue Melbourne
- Quotient Sciences, Mere Way, Ruddington Fields, Ruddington, Nottingham NG11 6JS, UK
| | - Amber Morgan
- Quotient Sciences, Mere Way, Ruddington Fields, Ruddington, Nottingham NG11 6JS, UK
| | - Carla Mariner
- Quotient Sciences, Mere Way, Ruddington Fields, Ruddington, Nottingham NG11 6JS, UK
| | - Maria Grazia Spillantini
- Department of Clinical Neurosciences, University of Cambridge, The Clifford Allbutt Building, Cambridge, CB2 0AH, UK
| | - Michal Wegrzynowicz
- Department of Clinical Neurosciences, University of Cambridge, The Clifford Allbutt Building, Cambridge, CB2 0AH, UK.; Laboratory of Molecular Basis of Neurodegeneration, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Jeffrey W Dalley
- Department of Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, UK; Department of Psychiatry, Hershel Smith Building for Brain and Mind Sciences, Addenbrooke's Hospital, Cambridge CB2 0SZ
| | - Simon Langer
- Department of Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, UK
| | - Sergey Ryazanov
- MODAG GmbH, Wendelsheim, Germany; Department of NMR based structural Biology, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | - Andrei Leonov
- MODAG GmbH, Wendelsheim, Germany; Department of NMR based structural Biology, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | - Christian Griesinger
- Department of NMR based structural Biology, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany
| | | | | | | | | | - Armin Giese
- MODAG GmbH, Wendelsheim, Germany; Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Germany.
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14
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Mendes D, Peixoto F, Oliveira MM, Andrade PB, Videira RA. Mitochondria research and neurodegenerative diseases: on the track to understanding the biological world of high complexity. Mitochondrion 2022; 65:67-79. [PMID: 35623557 DOI: 10.1016/j.mito.2022.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/20/2022] [Accepted: 05/22/2022] [Indexed: 12/18/2022]
Abstract
From the simple unicellular eukaryote to the highly complex multicellular organism like Human, mitochondrion emerges as a ubiquitous player to ensure the organism's functionality. It is popularly known as "the powerhouse of the cell" by its key role in ATP generation. However, our understanding of the physiological relevance of mitochondria is being challenged by data obtained in different fields. In this review, a short history of the mitochondria research field is presented, stressing the findings and questions that allowed the knowledge advances, and put mitochondrion as the main player of safeguarding organism life as well as a key to solve the puzzle of the neurodegenerative diseases.
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Affiliation(s)
- Daniela Mendes
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, no 228, Porto 4050-313, Portugal
| | - Francisco Peixoto
- Chemistry Center - Vila Real (CQ-VR), Biological and Environment Department, School of Life and Environmental Sciences, University of Trás-os-Montes e Alto Douro, UTAD, P.O. Box 1013, 5001-801 Vila Real, Portugal
| | - Maria M Oliveira
- Chemistry Center - Vila Real (CQ-VR), Chemistry Department, School of Life and Environmental Sciences, University of Trás-os-Montes e Alto Douro, UTAD, P.O. Box 1013, 5001-801 Vila Real, Portugal
| | - Paula B Andrade
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, no 228, Porto 4050-313, Portugal
| | - Romeu A Videira
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, no 228, Porto 4050-313, Portugal.
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15
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Yao QQ, Wen J, Perrett S, Wu S. Distinct lipid membrane-mediated pathways of Tau assembly revealed by single-molecule analysis. NANOSCALE 2022; 14:4604-4613. [PMID: 35260870 DOI: 10.1039/d1nr05960b] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The conversion of intrinsically disordered Tau to highly ordered amyloid aggregates is associated with a wide range of neurodegenerative diseases termed tauopathies. The presence of lipid bilayer membranes is a critical factor that accelerates the abnormal aggregation of Tau protein. However, the lipid membrane-induced conformational changes of Tau and the mechanism for the accelerated fibrillation remain elusive. In this study, single-molecule Förster resonance energy transfer (smFRET) and fluorescence correlation spectroscopy (FCS) were applied to detect the conformational changes and intermolecular interactions of full-length Tau in the presence of different concentrations of 1,2-dimyristoyl-sn-glycero-3-phosphatidylserine (DMPS) vesicles. The results show that the conformation of Tau becomes expanded with opening of the N-terminal and C-terminal domains of Tau upon binding to DMPS. At low DMPS concentrations, Tau forms oligomers with a partially extended conformation which facilitates the amyloid fibrillization process. At high DMPS concentrations, Tau monomer binds to lipid membranes in a fully expanded conformation at low density thus inhibiting intermolecular aggregation. Our study reveals the underlying mechanisms by which lipid membranes influence amyloid formation of Tau, providing a foundation for further understanding of the pathogenesis and physiology of the interplay between Tau protein and lipid membranes.
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Affiliation(s)
- Qiong-Qiong Yao
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, China.
- University of the Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Jitao Wen
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, China.
- University of the Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Sarah Perrett
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, China.
- University of the Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Si Wu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, China.
- University of the Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
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16
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Torres AK, Jara C, Park-Kang HS, Polanco CM, Tapia D, Alarcón F, de la Peña A, Llanquinao J, Vargas-Mardones G, Indo JA, Inestrosa NC, Tapia-Rojas C. Synaptic Mitochondria: An Early Target of Amyloid-β and Tau in Alzheimer's Disease. J Alzheimers Dis 2021; 84:1391-1414. [PMID: 34719499 DOI: 10.3233/jad-215139] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Alzheimer's disease (AD) is characterized by cognitive impairment and the presence of neurofibrillary tangles and senile plaques in the brain. Neurofibrillary tangles are composed of hyperphosphorylated tau, while senile plaques are formed by amyloid-β (Aβ) peptide. The amyloid hypothesis proposes that Aβ accumulation is primarily responsible for the neurotoxicity in AD. Multiple Aβ-mediated toxicity mechanisms have been proposed including mitochondrial dysfunction. However, it is unclear if it precedes Aβ accumulation or if is a consequence of it. Aβ promotes mitochondrial failure. However, amyloid β precursor protein (AβPP) could be cleaved in the mitochondria producing Aβ peptide. Mitochondrial-produced Aβ could interact with newly formed ones or with Aβ that enter the mitochondria, which may induce its oligomerization and contribute to further mitochondrial alterations, resulting in a vicious cycle. Another explanation for AD is the tau hypothesis, in which modified tau trigger toxic effects in neurons. Tau induces mitochondrial dysfunction by indirect and apparently by direct mechanisms. In neurons mitochondria are classified as non-synaptic or synaptic according to their localization, where synaptic mitochondrial function is fundamental supporting neurotransmission and hippocampal memory formation. Here, we focus on synaptic mitochondria as a primary target for Aβ toxicity and/or formation, generating toxicity at the synapse and contributing to synaptic and memory impairment in AD. We also hypothesize that phospho-tau accumulates in mitochondria and triggers dysfunction. Finally, we discuss that synaptic mitochondrial dysfunction occur in aging and correlates with age-related memory loss. Therefore, synaptic mitochondrial dysfunction could be a predisposing factor for AD or an early marker of its onset.
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Affiliation(s)
- Angie K Torres
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile.,Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudia Jara
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Han S Park-Kang
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Catalina M Polanco
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Diego Tapia
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Fabián Alarcón
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Adely de la Peña
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Jesus Llanquinao
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Gabriela Vargas-Mardones
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Javiera A Indo
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
| | - Nibaldo C Inestrosa
- Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
| | - Cheril Tapia-Rojas
- Laboratory of Neurobiology of Aging, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebasti´n Sede Los Leones, Santiago, Chile
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17
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Sallaberry CA, Voss BJ, Majewski J, Biernat J, Mandelkow E, Chi EY, Vander Zanden CM. Tau and Membranes: Interactions That Promote Folding and Condensation. Front Cell Dev Biol 2021; 9:725241. [PMID: 34621743 PMCID: PMC8491580 DOI: 10.3389/fcell.2021.725241] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/31/2021] [Indexed: 12/15/2022] Open
Abstract
Tau misfolding and assembly is linked to a number of neurodegenerative diseases collectively described as tauopathies, including Alzheimer’s disease (AD) and Parkinson’s disease. Anionic cellular membranes, such as the cytosolic leaflet of the plasma membrane, are sites that concentrate and neutralize tau, primarily due to electrostatic interactions with tau’s microtubule binding repeat domain (RD). In addition to electrostatic interactions with lipids, tau also has interactions with membrane proteins, which are important for tau’s cellular functions. Tau also interacts with lipid tails to facilitate direct translocation across the membrane and can form stable protein-lipid complexes involved in cell-to-cell transport. Concentrated tau monomers at the membrane surface can form reversible condensates, change secondary structures, and induce oligomers, which may eventually undergo irreversible crosslinking and fibril formation. These β-sheet rich tau structures are capable of disrupting membrane organization and are toxic in cell-based assays. Given the evidence for relevant membrane-based tau assembly, we review the emerging hypothesis that polyanionic membranes may serve as a site for phase-separated tau condensation. Membrane-mediated phase separation may have important implications for regulating tau folding/misfolding, and may be a powerful mechanism to spatially direct tau for native membrane-mediated functions.
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Affiliation(s)
- Chad A Sallaberry
- Department of Chemistry & Biochemistry, University of Colorado Colorado Springs, Colorado Springs, CO, United States
| | - Barbie J Voss
- Department of Chemistry & Biochemistry, University of Colorado Colorado Springs, Colorado Springs, CO, United States
| | - Jaroslaw Majewski
- Division of Molecular and Cellular Biosciences, National Science Foundation, Alexandria, VA, United States.,Department of Chemical & Biological Engineering, Center for Biomedical Engineering, The University of New Mexico, Albuquerque, NM, United States.,Theoretical Biology and Biophysics Division, Los Alamos National Laboratory, Los Alamos, NM, United States
| | - Jacek Biernat
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Eckhard Mandelkow
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Center of Advanced European Studies and Research (CAESAR) Center, Bonn, Germany.,Department of Neurodegenerative Disease and Geriatric Psychiatry, Medical School, University of Bonn, Bonn, Germany
| | - Eva Y Chi
- Department of Chemical & Biological Engineering, Center for Biomedical Engineering, The University of New Mexico, Albuquerque, NM, United States
| | - Crystal M Vander Zanden
- Department of Chemistry & Biochemistry, University of Colorado Colorado Springs, Colorado Springs, CO, United States
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18
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Sharif NA. Therapeutic Drugs and Devices for Tackling Ocular Hypertension and Glaucoma, and Need for Neuroprotection and Cytoprotective Therapies. Front Pharmacol 2021; 12:729249. [PMID: 34603044 PMCID: PMC8484316 DOI: 10.3389/fphar.2021.729249] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/18/2021] [Indexed: 12/11/2022] Open
Abstract
Damage to the optic nerve and the death of associated retinal ganglion cells (RGCs) by elevated intraocular pressure (IOP), also known as glaucoma, is responsible for visual impairment and blindness in millions of people worldwide. The ocular hypertension (OHT) and the deleterious mechanical forces it exerts at the back of the eye, at the level of the optic nerve head/optic disc and lamina cribosa, is the only modifiable risk factor associated with glaucoma that can be treated. The elevated IOP occurs due to the inability of accumulated aqueous humor (AQH) to egress from the anterior chamber of the eye due to occlusion of the major outflow pathway, the trabecular meshwork (TM) and Schlemm’s canal (SC). Several different classes of pharmaceutical agents, surgical techniques and implantable devices have been developed to lower and control IOP. First-line drugs to promote AQH outflow via the uveoscleral outflow pathway include FP-receptor prostaglandin (PG) agonists (e.g., latanoprost, travoprost and tafluprost) and a novel non-PG EP2-receptor agonist (omidenepag isopropyl, Eybelis®). TM/SC outflow enhancing drugs are also effective ocular hypotensive agents (e.g., rho kinase inhibitors like ripasudil and netarsudil; and latanoprostene bunod, a conjugate of a nitric oxide donor and latanoprost). One of the most effective anterior chamber AQH microshunt devices is the Preserflo® microshunt which can lower IOP down to 10–13 mmHg. Other IOP-lowering drugs and devices on the horizon will be also discussed. Additionally, since elevated IOP is only one of many risk factors for development of glaucomatous optic neuropathy, a treatise of the role of inflammatory neurodegeneration of the optic nerve and retinal ganglion cells and appropriate neuroprotective strategies to mitigate this disease will also be reviewed and discussed.
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Affiliation(s)
- Najam A Sharif
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
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19
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Kurokin I, Lauer AA, Janitschke D, Winkler J, Theiss EL, Griebsch LV, Pilz SM, Matschke V, van der Laan M, Grimm HS, Hartmann T, Grimm MOW. Targeted Lipidomics of Mitochondria in a Cellular Alzheimer's Disease Model. Biomedicines 2021; 9:biomedicines9081062. [PMID: 34440266 PMCID: PMC8393816 DOI: 10.3390/biomedicines9081062] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 01/12/2023] Open
Abstract
Alzheimer’s disease (AD) is neuropathologically characterized by the accumulation of Amyloid-β (Aβ) in senile plaques derived from amyloidogenic processing of a precursor protein (APP). Recently, changes in mitochondrial function have become in the focus of the disease. Whereas a link between AD and lipid-homeostasis exists, little is known about potential alterations in the lipid composition of mitochondria. Here, we investigate potential changes in the main mitochondrial phospholipid classes phosphatidylcholine, phosphatidylethanolamine and the corresponding plasmalogens and lyso-phospholipids of a cellular AD-model (SH-SY5Y APPswedish transfected cells), comparing these results with changes in cell-homogenates. Targeted shotgun-lipidomics revealed lipid alterations to be specific for mitochondria and cannot be predicted from total cell analysis. In particular, lipids containing three and four times unsaturated fatty acids (FA X:4), such as arachidonic-acid, are increased, whereas FA X:6 or X:5, such as eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), are decreased. Additionally, PE plasmalogens are increased in contrast to homogenates. Results were confirmed in another cellular AD model, having a lower affinity to amyloidogenic APP processing. Besides several similarities, differences in particular in PE species exist, demonstrating that differences in APP processing might lead to specific changes in lipid homeostasis in mitochondria. Importantly, the observed lipid alterations are accompanied by changes in the carnitine carrier system, also suggesting an altered mitochondrial functionality.
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Affiliation(s)
- Irina Kurokin
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Anna Andrea Lauer
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Daniel Janitschke
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Jakob Winkler
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Elena Leoni Theiss
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Lea Victoria Griebsch
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Sabrina Melanie Pilz
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Veronika Matschke
- Department of Cytology, Institute of Anatomy, Medical Faculty, Ruhr University Bochum, D-44801 Bochum, Germany;
| | - Martin van der Laan
- Medical Biochemistry & Molecular Biology, Center for Molecular Signaling PZMS, Saarland University Medical School, 66421 Homburg, Germany;
| | - Heike Sabine Grimm
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Tobias Hartmann
- Deutsches Institut für Demenzprävention, Saarland University, 66421 Homburg, Germany;
| | - Marcus Otto Walter Grimm
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
- Deutsches Institut für Demenzprävention, Saarland University, 66421 Homburg, Germany;
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
- Correspondence:
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20
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Naveh Tassa S, Ben Zichri S, Lacham-Hartman S, Oren O, Slobodnik Z, Eremenko E, Toiber D, Jelinek R, Papo N. A Mechanism for the Inhibition of Tau Neurotoxicity: Studies with Artificial Membranes, Isolated Mitochondria, and Intact Cells. ACS Chem Neurosci 2021; 12:1563-1577. [PMID: 33904703 DOI: 10.1021/acschemneuro.1c00045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
It is currently believed that molecular agents that specifically bind to and neutralize the toxic proteins/peptides, amyloid β (Aβ42), tau, and the tau-derived peptide PHF6, hold the key to attenuating the progression of Alzheimer's disease (AD). We thus tested our previously developed nonaggregating Aβ42 double mutant (Aβ42DM) as a multispecific binder for three AD-associated molecules, wild-type Aβ42, the tauK174Q mutant, and a synthetic PHF6 peptide. Aβ42DM acted as a functional inhibitor of these molecules in in vitro assays and in neuronal cell-based models of AD. The double mutant bound both cytotoxic tauK174Q and synthetic PHF6 and protected neuronal cells from the accumulation of tau in cell lysates and mitochondria. Aβ42DM also reduced toxic intracellular levels of calcium and the overall cell toxicity induced by overexpressed tau, synthetic PHF6, Aβ42, or a combination of PHF6and Aβ42. Aβ42DM inhibited PHF6-induced overall mitochondrial dysfunction: In particular, Aβ42DM inhibited PHF6-induced damage to submitochondrial particles (SMPs) and suppressed PHF6-induced elevation of the ζ-potential of inverted SMPs (proxy for the inner mitochondrial membrane, IMM). PHF6 reduced the lipid fluidity of cardiolipin/DOPC vesicles (that mimic the IMM) but not DOPC (which mimics the outer mitochondrial membrane), and this effect was inhibited by Aβ42DM. This inhibition may be explained by the conformational changes in PHF6 induced by Aβ42DM in solution and in membrane mimetics. On this basis, the paper presents a mechanistic explanation for the inhibitory activity of Aβ42DM against Aβ42- and tau-induced membrane permeability and cell toxicity and provides confirmatory evidence for its protective function in neuronal cells.
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Affiliation(s)
- Segev Naveh Tassa
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Shani Ben Zichri
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Shiran Lacham-Hartman
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Ofek Oren
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Zeev Slobodnik
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Ekaterina Eremenko
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Debra Toiber
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Raz Jelinek
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Niv Papo
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
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21
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Tau internalization: A complex step in tau propagation. Ageing Res Rev 2021; 67:101272. [PMID: 33571704 DOI: 10.1016/j.arr.2021.101272] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 12/04/2020] [Accepted: 02/04/2021] [Indexed: 12/16/2022]
Abstract
Aggregation of microtubule-associated protein Tau (MAPT) may underlie abnormalities of the intracellular matrix and neuronal death in tauopathies. Tau proteins can be secreted to the extracellular space and internalized into adjacent cells. The internalization of Tau is a complex but critical step in Tau propagation. This review summarizes the internalization pathways of Tau, including macropinocytosis, Clathrin-mediated endocytosis (CME), lipid raft dependent endocytosis, Tunneling nanotubes dependent endocytosis (TNTs) and phagocytosis. The conformation of Tau fibrils and the types of recipient cell determine the internalization pathway. However, the HSPGs-dependent endocytosis seems to be the predominant pathway of Tau internalization. After internalization, Tau fibrils undergo clearance and seeding. Imbalance among Tau secretion, internalization and clearance may result in the propagation of misfolded Tau in the brain, thereby inducing Tauopathies. A better understanding of the internalization of Tau proteins may facilitate the discovery of novel therapeutic strategies to block the propagation of Tau pathology.
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22
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Bok E, Leem E, Lee BR, Lee JM, Yoo CJ, Lee EM, Kim J. Role of the Lipid Membrane and Membrane Proteins in Tau Pathology. Front Cell Dev Biol 2021; 9:653815. [PMID: 33996814 PMCID: PMC8119898 DOI: 10.3389/fcell.2021.653815] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/09/2021] [Indexed: 12/12/2022] Open
Abstract
Abnormal accumulation of misfolded tau aggregates is a pathological hallmark of various tauopathies including Alzheimer’s disease (AD). Although tau is a cytosolic microtubule-associated protein enriched in neurons, it is also found in extracellular milieu, such as interstitial fluid, cerebrospinal fluid, and blood. Accumulating evidence showed that pathological tau spreads along anatomically connected areas in the brain through intercellular transmission and templated misfolding, thereby inducing neurodegeneration and cognitive dysfunction. In line with this, the spatiotemporal spreading of tau pathology is closely correlated with cognitive decline in AD patients. Although the secretion and uptake of tau involve multiple different pathways depending on tau species and cell types, a growing body of evidence suggested that tau is largely secreted in a vesicle-free forms. In this regard, the interaction of vesicle-free tau with membrane is gaining growing attention due to its importance for both of tau secretion and uptake as well as aggregation. Here, we review the recent literature on the mechanisms of the tau-membrane interaction and highlights the roles of lipids and proteins at the membrane in the tau-membrane interaction as well as tau aggregation.
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Affiliation(s)
- Eugene Bok
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Eunju Leem
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Bo-Ram Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Ji Min Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea.,School of Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Chang Jae Yoo
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Eun Mi Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Jaekwang Kim
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
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23
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Falabella M, Vernon HJ, Hanna MG, Claypool SM, Pitceathly RDS. Cardiolipin, Mitochondria, and Neurological Disease. Trends Endocrinol Metab 2021; 32:224-237. [PMID: 33640250 PMCID: PMC8277580 DOI: 10.1016/j.tem.2021.01.006] [Citation(s) in RCA: 106] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 02/07/2023]
Abstract
Over the past decade, it has become clear that lipid homeostasis is central to cellular metabolism. Lipids are particularly abundant in the central nervous system (CNS) where they modulate membrane fluidity, electric signal transduction, and synaptic stabilization. Abnormal lipid profiles reported in Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and traumatic brain injury (TBI), are further support for the importance of lipid metablism in the nervous system. Cardiolipin (CL), a mitochondria-exclusive phospholipid, has recently emerged as a focus of neurodegenerative disease research. Aberrant CL content, structure, and localization are linked to impaired neurogenesis and neuronal dysfunction, contributing to aging and the pathogenesis of several neurodegenerative diseases, such as AD and PD. Furthermore, the highly tissue-specific acyl chain composition of CL confers it significant potential as a biomarker to diagnose and monitor the progression in several neurological diseases. CL also represents a potential target for pharmacological strategies aimed at treating neurodegeneration. Given the equipoise that currently exists between CL metabolism, mitochondrial function, and neurological disease, we review the role of CL in nervous system physiology and monogenic and neurodegenerative disease pathophysiology, in addition to its potential application as a biomarker and pharmacological target.
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Affiliation(s)
- Micol Falabella
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology, London, UK
| | - Hilary J Vernon
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael G Hanna
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, London, UK
| | - Steven M Claypool
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert D S Pitceathly
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, London, UK.
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24
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Gonzalez-Garcia M, Fusco G, De Simone A. Membrane Interactions and Toxicity by Misfolded Protein Oligomers. Front Cell Dev Biol 2021; 9:642623. [PMID: 33791300 PMCID: PMC8006268 DOI: 10.3389/fcell.2021.642623] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/08/2021] [Indexed: 01/13/2023] Open
Abstract
The conversion of otherwise soluble proteins into insoluble amyloid aggregates is associated with a range of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases, as well as non-neuropathic conditions such as type II diabetes and systemic amyloidoses. It is increasingly evident that the most pernicious species among those forming during protein aggregation are small prefibrillar oligomers. In this review, we describe the recent progress in the characterization of the cellular and molecular interactions by toxic misfolded protein oligomers. A fundamental interaction by these aggregates involves biological membranes, resulting in two major model mechanisms at the onset of the cellular toxicity. These include the membrane disruption model, resulting in calcium imbalance, mitochondrial dysfunction and intracellular reactive oxygen species, and the direct interaction with membrane proteins, leading to the alteration of their native function. A key challenge remains in the characterization of transient interactions involving heterogeneous protein aggregates. Solving this task is crucial in the quest of identifying suitable therapeutic approaches to suppress the cellular toxicity in protein misfolding diseases.
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Affiliation(s)
- Mario Gonzalez-Garcia
- Department of Life Sciences, Imperial College London, South Kensington, United Kingdom
| | - Giuliana Fusco
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge, United Kingdom
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, South Kensington, United Kingdom.,Department of Pharmacy, University of Naples Federico II, Naples, Italy
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25
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Caruana M, Camilleri A, Farrugia MY, Ghio S, Jakubíčková M, Cauchi RJ, Vassallo N. Extract from the Marine Seaweed Padina pavonica Protects Mitochondrial Biomembranes from Damage by Amyloidogenic Peptides. Molecules 2021; 26:1444. [PMID: 33799979 PMCID: PMC7962105 DOI: 10.3390/molecules26051444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 11/30/2022] Open
Abstract
The identification of compounds which protect the double-membrane of mitochondrial organelles from disruption by toxic confomers of amyloid proteins may offer a therapeutic strategy to combat human neurodegenerative diseases. Here, we exploited an extract from the marine brown seaweed Padina pavonica (PPE) as a vital source of natural bioactive compounds to protect mitochondrial membranes against insult by oligomeric aggregates of the amyloidogenic proteins amyloid-β (Aβ), α-synuclein (α-syn) and tau, which are currently considered to be major targets for drug discovery in Alzheimer's disease (AD) and Parkinson's disease (PD). We show that PPE manifested a significant inhibitory effect against swelling of isolated mitochondria exposed to the amyloid oligomers, and attenuated the release of cytochrome c from the mitochondria. Using cardiolipin-enriched synthetic lipid membranes, we also show that dye leakage from fluorophore-loaded vesicles and formation of channel-like pores in planar bilayer membranes are largely prevented by incubating the oligomeric aggregates with PPE. Lastly, we demonstrate that PPE curtails the ability of Aβ42 and α-syn monomers to self-assemble into larger β-aggregate structures, as well as potently disrupts their respective amyloid fibrils. In conclusion, the mito-protective and anti-aggregator biological activities of Padina pavonica extract may be of therapeutic value in neurodegenerative proteinopathies, such as AD and PD.
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Affiliation(s)
- Mario Caruana
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, 2023 Msida, Malta
| | - Angelique Camilleri
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, 2023 Msida, Malta
| | - Maria Ylenia Farrugia
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, 2023 Msida, Malta
| | - Stephanie Ghio
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, 2023 Msida, Malta
| | - Michaela Jakubíčková
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Department of Experimental Biology, Faculty of Science, Masaryk University, 60300 Brno, Czech Republic
| | - Ruben J. Cauchi
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, 2023 Msida, Malta
| | - Neville Vassallo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, 2023 Msida, Malta; (M.C.); (A.C.); (M.Y.F.); (S.G.); (M.J.); (R.J.C.)
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, 2023 Msida, Malta
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26
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Niewiadomska G, Niewiadomski W, Steczkowska M, Gasiorowska A. Tau Oligomers Neurotoxicity. Life (Basel) 2021; 11:28. [PMID: 33418848 PMCID: PMC7824853 DOI: 10.3390/life11010028] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 12/11/2022] Open
Abstract
Although the mechanisms of toxic activity of tau are not fully recognized, it is supposed that the tau toxicity is related rather not to insoluble tau aggregates but to its intermediate forms. It seems that neurofibrillar tangles (NFTs) themselves, despite being composed of toxic tau, are probably neither necessary nor sufficient for tau-induced neuronal dysfunction and toxicity. Tau oligomers (TauOs) formed during the early stages of tau aggregation are the pathological forms that play a key role in eliciting the loss of neurons and behavioral impairments in several neurodegenerative disorders called tauopathies. They can be found in tauopathic diseases, the most common of which is Alzheimer's disease (AD). Evidence of co-occurrence of b-amyloid, α-synuclein, and tau into their most toxic forms, i.e., oligomers, suggests that these species interact and influence each other's aggregation in several tauopathies. The mechanism responsible for oligomeric tau neurotoxicity is a subject of intensive investigation. In this review, we summarize the most recent literature on the damaging effect of TauOs on the stability of the genome and the function of the nucleus, energy production and mitochondrial function, cell signaling and synaptic plasticity, the microtubule assembly, neuronal cytoskeleton and axonal transport, and the effectiveness of the protein degradation system.
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Affiliation(s)
- Grazyna Niewiadomska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland
| | - Wiktor Niewiadomski
- Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland; (W.N.); (M.S.); (A.G.)
| | - Marta Steczkowska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland; (W.N.); (M.S.); (A.G.)
| | - Anna Gasiorowska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland; (W.N.); (M.S.); (A.G.)
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27
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Affiliation(s)
- Neville Vassallo
- Department of Physiology & Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida MSD 2080, Malta
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28
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Saghir AE, Farrugia G, Vassallo N. The human islet amyloid polypeptide in protein misfolding disorders: Mechanisms of aggregation and interaction with biomembranes. Chem Phys Lipids 2020; 234:105010. [PMID: 33227292 DOI: 10.1016/j.chemphyslip.2020.105010] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/06/2020] [Accepted: 11/09/2020] [Indexed: 02/09/2023]
Abstract
Human islet amyloid polypeptide (hIAPP), otherwise known as amylin, is a 37-residue peptide hormone which is reported to be a common factor in protein misfolding disorders such as type-2 diabetes mellitus, Alzheimer's disease and Parkinson's disease, due to deposition of insoluble hIAPP amyloid in the pancreas and brain. Multiple studies point to the importance of the peptide's interaction with biological membranes and the cytotoxicity of hIAPP species. Here, we discuss the aggregation pathways of hIAPP amyloid fibril formation and focus on the complex interplay between membrane-mediated assembly of hIAPP and the associated mechanisms of membrane damage caused by the peptide species. Mitochondrial membranes, which are unique in their lipid composition, are proposed as prime targets for the early intracellular formation of hIAPP toxic entities. We suggest that future studies should include more physiologically-relevant and in-cell studies to allow a more accurate model of in vivo interactions. Finally, we underscore an urgent need for developing effective therapeutic strategies aimed at hindering hIAPP-phospholipid interactions.
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Affiliation(s)
- Adam El Saghir
- Dept. of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Gianluca Farrugia
- Dept. of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Neville Vassallo
- Dept. of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta.
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29
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Cardiolipin in Immune Signaling and Cell Death. Trends Cell Biol 2020; 30:892-903. [DOI: 10.1016/j.tcb.2020.09.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 08/30/2020] [Accepted: 09/07/2020] [Indexed: 12/25/2022]
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30
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Collin F, Cerlati O, Couderc F, Lonetti B, Marty JD, Mingotaud AF. Multidisciplinary analysis of protein-lipid interactions and implications in neurodegenerative disorders. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.116059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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31
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Farrugia MY, Caruana M, Ghio S, Camilleri A, Farrugia C, Cauchi RJ, Cappelli S, Chiti F, Vassallo N. Toxic oligomers of the amyloidogenic HypF-N protein form pores in mitochondrial membranes. Sci Rep 2020; 10:17733. [PMID: 33082392 PMCID: PMC7575562 DOI: 10.1038/s41598-020-74841-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/06/2020] [Indexed: 12/30/2022] Open
Abstract
Studies on the amyloidogenic N-terminal domain of the E. coli HypF protein (HypF-N) have contributed significantly to a detailed understanding of the pathogenic mechanisms in neurodegenerative diseases characterised by the formation of misfolded oligomers, by proteins such as amyloid-β, α-synuclein and tau. Given that both cell membranes and mitochondria are increasingly recognised as key targets of oligomer toxicity, we investigated the damaging effects of aggregates of HypF-N on mitochondrial membranes. Essentially, we found that HypF-N oligomers characterised by high surface hydrophobicity (type A) were able to trigger a robust permeabilisation of mito-mimetic liposomes possessing cardiolipin-rich membranes and dysfunction of isolated mitochondria, as demonstrated by a combination of mitochondrial shrinking, lowering of mitochondrial membrane potential and cytochrome c release. Furthermore, using single-channel electrophysiology recordings we obtained evidence that the type A aggregates induced currents reflecting formation of ion-conducting pores in mito-mimetic planar phospholipid bilayers, with multi-level conductances ranging in the hundreds of pS at negative membrane voltages. Conversely, HypF-N oligomers with low surface hydrophobicity (type B) could not permeabilise or porate mitochondrial membranes. These results suggest an inherent toxicity of membrane-active aggregates of amyloid-forming proteins to mitochondria, and that targeting of oligomer-mitochondrial membrane interactions might therefore afford protection against such damage.
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Affiliation(s)
- Maria Ylenia Farrugia
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Mario Caruana
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Stephanie Ghio
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Angelique Camilleri
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | | | - Ruben J Cauchi
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Sara Cappelli
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50134, Florence, Italy
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50134, Florence, Italy
| | - Neville Vassallo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta.
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32
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Insights into Disease-Associated Tau Impact on Mitochondria. Int J Mol Sci 2020; 21:ijms21176344. [PMID: 32882957 PMCID: PMC7503371 DOI: 10.3390/ijms21176344] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/23/2022] Open
Abstract
Abnormal tau protein aggregation in the brain is a hallmark of tauopathies, such as frontotemporal lobar degeneration and Alzheimer’s disease. Substantial evidence has been linking tau to neurodegeneration, but the underlying mechanisms have yet to be clearly identified. Mitochondria are paramount organelles in neurons, as they provide the main source of energy (adenosine triphosphate) to these highly energetic cells. Mitochondrial dysfunction was identified as an early event of neurodegenerative diseases occurring even before the cognitive deficits. Tau protein was shown to interact with mitochondrial proteins and to impair mitochondrial bioenergetics and dynamics, leading to neurotoxicity. In this review, we discuss in detail the different impacts of disease-associated tau protein on mitochondrial functions, including mitochondrial transport, network dynamics, mitophagy and bioenergetics. We also give new insights about the effects of abnormal tau protein on mitochondrial neurosteroidogenesis, as well as on the endoplasmic reticulum-mitochondria coupling. A better understanding of the pathomechanisms of abnormal tau-induced mitochondrial failure may help to identify new targets for therapeutic interventions.
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33
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Tan JX, Finkel T. Mitochondria as intracellular signaling platforms in health and disease. J Cell Biol 2020; 219:e202002179. [PMID: 32320464 PMCID: PMC7199861 DOI: 10.1083/jcb.202002179] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/02/2020] [Accepted: 04/03/2020] [Indexed: 12/15/2022] Open
Abstract
Mitochondria, long viewed solely in the context of bioenergetics, are increasingly emerging as critical hubs for intracellular signaling. Due to their bacterial origin, mitochondria possess their own genome and carry unique lipid components that endow these organelles with specialized properties to help orchestrate multiple signaling cascades. Mitochondrial signaling modulates diverse pathways ranging from metabolism to redox homeostasis to cell fate determination. Here, we review recent progress in our understanding of how mitochondria serve as intracellular signaling platforms with a particular emphasis on lipid-mediated signaling, innate immune activation, and retrograde signaling. We further discuss how these signaling properties might potentially be exploited to develop new therapeutic strategies for a range of age-related conditions.
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Affiliation(s)
- Jay X. Tan
- Aging Institute, University of Pittsburgh School of Medicine/University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Toren Finkel
- Aging Institute, University of Pittsburgh School of Medicine/University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Clement A, Wiborg O, Asuni AA. Steps Towards Developing Effective Treatments for Neuropsychiatric Disturbances in Alzheimer's Disease: Insights From Preclinical Models, Clinical Data, and Future Directions. Front Aging Neurosci 2020; 12:56. [PMID: 32210790 PMCID: PMC7068814 DOI: 10.3389/fnagi.2020.00056] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/18/2020] [Indexed: 01/10/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia worldwide. It is mostly known for its devastating effect on memory and learning but behavioral alterations commonly known as neuropsychiatric disturbances (NPDs) are also characteristics of the disease. These include apathy, depression-like behavior, and sleep disturbances, and they all contribute to an increased caregiver burden and earlier institutionalization. The interaction between NPDs and AD pathology is not well understood, but the consensus is that they contribute to disease progression and faster decline. Consequently, recognizing and treating NPDs might improve AD pathology and increase the quality of life for both patients and caregivers. In this review article, we examine previous and current literature on apathy, depressive symptoms, and sleep disturbances in AD patients and preclinical AD mechanistic models. We hypothesize that tau accumulation, beta-amyloid (Aβ) aggregation, neuroinflammation, mitochondrial damage, and loss of the locus coeruleus (LC)-norepinephrine (NE) system all collectively impact the development of NPDs and contribute synergistically to AD pathology. Targeting more than one of these processes might provide the most optimal strategy for treating NPDs and AD. The development of such clinical approaches would be preceded by preclinical studies, for which robust and reliable mechanistic models of NPD-like behavior are needed. Thus, developing effective preclinical research models represents an important step towards a better understanding of NPDs in AD.
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Affiliation(s)
- Amalie Clement
- Laboratory of Neurobiology, Department of Health, Science and Technology, Aalborg University, Aalborg, Denmark
- Department of Physiology and Symptoms, H. Lundbeck A/S, Copenhagen, Denmark
| | - Ove Wiborg
- Laboratory of Neurobiology, Department of Health, Science and Technology, Aalborg University, Aalborg, Denmark
| | - Ayodeji A. Asuni
- Department of Physiology and Symptoms, H. Lundbeck A/S, Copenhagen, Denmark
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Quntanilla RA, Tapia-Monsalves C. The Role of Mitochondrial Impairment in Alzheimer´s Disease Neurodegeneration: The Tau Connection. Curr Neuropharmacol 2020; 18:1076-1091. [PMID: 32448104 PMCID: PMC7709157 DOI: 10.2174/1570159x18666200525020259] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/23/2020] [Accepted: 05/17/2020] [Indexed: 12/12/2022] Open
Abstract
Accumulative evidence has shown that mitochondrial dysfunction plays a pivotal role in the pathogenesis of Alzheimer's disease (AD). Mitochondrial impairment actively contributes to the synaptic and cognitive failure that characterizes AD. The presence of soluble pathological forms of tau like hyperphosphorylated at Ser396 and Ser404 and cleaved at Asp421 by caspase 3, negatively impacts mitochondrial bioenergetics, transport, and morphology in neurons. These adverse effects against mitochondria health will contribute to the synaptic impairment and cognitive decline in AD. Current studies suggest that mitochondrial failure induced by pathological tau forms is likely the result of the opening of the mitochondrial permeability transition pore (mPTP). mPTP is a mitochondrial mega-channel that is activated by increases in calcium and is associated with mitochondrial stress and apoptosis. This structure is composed of different proteins, where Ciclophilin D (CypD) is considered to be the primary mediator of mPTP activation. Also, new studies suggest that mPTP contributes to Aβ pathology and oxidative stress in AD. Further, inhibition of mPTP through the reduction of CypD expression prevents cognitive and synaptic impairment in AD mouse models. More importantly, tau protein contributes to the physiological regulation of mitochondria through the opening/interaction with mPTP in hippocampal neurons. Therefore, in this paper, we will discuss evidence that suggests an important role of pathological forms of tau against mitochondrial health. Also, we will discuss the possible role of mPTP in the mitochondrial impairment produced by the presence of tau pathology and its impact on synaptic function present in AD.
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Affiliation(s)
- Rodrigo A. Quntanilla
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de la Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Carola Tapia-Monsalves
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de la Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
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