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Lee E, Park H, Kim S. Transcellular transmission and molecular heterogeneity of aggregation-prone proteins in neurodegenerative diseases. Mol Cells 2024; 47:100089. [PMID: 38971320 DOI: 10.1016/j.mocell.2024.100089] [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: 05/14/2024] [Revised: 06/26/2024] [Accepted: 07/01/2024] [Indexed: 07/08/2024] Open
Abstract
The accumulation of aggregation-prone proteins in a specific neuronal population is a common feature of neurodegenerative diseases, which is correlated with the development of pathological lesions in diseased brains. The formation and progression of pathological protein aggregates in susceptible neurons induce cellular dysfunction, resulting in progressive degeneration. Moreover, recent evidence supports the notion that the cell-to-cell transmission of pathological protein aggregates may be involved in the onset and progression of many neurodegenerative diseases. Indeed, several studies have identified different pathological aggregate strains. Although how these different aggregate strains form remains unclear, a variety of biomolecular compositions or cross-seeding events promoted by the presence of other protein aggregates in the cellular environment may affect the formation of different strains of pathological aggregates, which in turn can influence complex pathologies in diseased brains. In this review, we summarize the recent results regarding cell-to-cell transmission and the molecular heterogeneity of pathological aggregate strains, raising key questions for future research directions.
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Affiliation(s)
- Eunmin Lee
- Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Chungbuk 28644, Korea
| | - Hyeonwoo Park
- Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Chungbuk 28644, Korea
| | - Sangjune Kim
- Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Chungbuk 28644, Korea.
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2
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Skeens A, Siriwardhana C, Massinople SE, Wunder MM, Ellis ZL, Keith KM, Girman T, Frey SL, Legleiter J. The polyglutamine domain is the primary driver of seeding in huntingtin aggregation. PLoS One 2024; 19:e0298323. [PMID: 38483973 PMCID: PMC10939245 DOI: 10.1371/journal.pone.0298323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 01/22/2024] [Indexed: 03/17/2024] Open
Abstract
Huntington's Disease (HD) is a fatal, neurodegenerative disease caused by aggregation of the huntingtin protein (htt) with an expanded polyglutamine (polyQ) domain into amyloid fibrils. Htt aggregation is modified by flanking sequences surrounding the polyQ domain as well as the binding of htt to lipid membranes. Upon fibrillization, htt fibrils are able to template the aggregation of monomers into fibrils in a phenomenon known as seeding, and this process appears to play a critical role in cell-to-cell spread of HD. Here, exposure of C. elegans expressing a nonpathogenic N-terminal htt fragment (15-repeat glutamine residues) to preformed htt-exon1 fibrils induced inclusion formation and resulted in decreased viability in a dose dependent manner, demonstrating that seeding can induce toxic aggregation of nonpathogenic forms of htt. To better understand this seeding process, the impact of flanking sequences adjacent to the polyQ stretch, polyQ length, and the presence of model lipid membranes on htt seeding was investigated. Htt seeding readily occurred across polyQ lengths and was independent of flanking sequence, suggesting that the structured polyQ domain within fibrils is the key contributor to the seeding phenomenon. However, the addition of lipid vesicles modified seeding efficiency in a manner suggesting that seeding primarily occurs in bulk solution and not at the membrane interface. In addition, fibrils formed in the presence of lipid membranes displayed similar seeding efficiencies. Collectively, this suggests that the polyQ domain that forms the amyloid fibril core is the main driver of seeding in htt aggregation.
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Affiliation(s)
- Adam Skeens
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Chathuranga Siriwardhana
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Sophia E. Massinople
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Michelle M. Wunder
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Zachary L. Ellis
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Kaitlyn M. Keith
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Tyler Girman
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Shelli L. Frey
- The Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania, United States of America
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
- Rockefeller Neurosciences Institutes, West Virginia University, Morgantown, West Virginia, United States of America
- Department of Neuroscience, West Virginia University, Morgantown, West Virginia, United States of America
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3
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Dinamarca MC, Colombo L, Brykczynska U, Grimm A, Fruh I, Hossain I, Gabriel D, Eckert A, Müller M, Pecho-Vrieseling E. Transmission-selective muscle pathology induced by the active propagation of mutant huntingtin across the human neuromuscular synapse. Front Mol Neurosci 2024; 16:1287510. [PMID: 38235149 PMCID: PMC10791992 DOI: 10.3389/fnmol.2023.1287510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 11/27/2023] [Indexed: 01/19/2024] Open
Abstract
Neuron-to-neuron transmission of aggregation-prone, misfolded proteins may potentially explain the spatiotemporal accumulation of pathological lesions in the brains of patients with neurodegenerative protein-misfolding diseases (PMDs). However, little is known about protein transmission from the central nervous system to the periphery, or how this propagation contributes to PMD pathology. To deepen our understanding of these processes, we established two functional neuromuscular systems derived from human iPSCs. One was suitable for long-term high-throughput live-cell imaging and the other was adapted to a microfluidic system assuring that connectivity between motor neurons and muscle cells was restricted to the neuromuscular junction. We show that the Huntington's disease (HD)-associated mutant HTT exon 1 protein (mHTTEx1) is transmitted from neurons to muscle cells across the human neuromuscular junction. We found that transmission is an active and dynamic process that starts before aggregate formation and is regulated by synaptic activity. We further found that transmitted mHTTEx1 causes HD-relevant pathology at both molecular and functional levels in human muscle cells, even in the presence of the ubiquitous expression of mHTTEx1. In conclusion, we have uncovered a causal link between mHTTEx1 synaptic transmission and HD pathology, highlighting the therapeutic potential of blocking toxic protein transmission in PMDs.
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Affiliation(s)
- Margarita C. Dinamarca
- Neuronal Development and Degeneration Laboratory, Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Laura Colombo
- Neuronal Development and Degeneration Laboratory, Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Urszula Brykczynska
- Neuronal Development and Degeneration Laboratory, Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Amandine Grimm
- Neurobiology Laboratory for Brain Aging and Mental Health, Transfaculty Research Platform, Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland
| | - Isabelle Fruh
- Biomedical Research, Novartis Pharma AG, Novartis Campus, Basel, Switzerland
| | - Imtiaz Hossain
- Biomedical Research, Novartis Pharma AG, Novartis Campus, Basel, Switzerland
| | - Daniela Gabriel
- Biomedical Research, Novartis Pharma AG, Novartis Campus, Basel, Switzerland
| | - Anne Eckert
- Neurobiology Laboratory for Brain Aging and Mental Health, Transfaculty Research Platform, Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland
| | - Matthias Müller
- Biomedical Research, Novartis Pharma AG, Novartis Campus, Basel, Switzerland
| | - Eline Pecho-Vrieseling
- Neuronal Development and Degeneration Laboratory, Department of Biomedicine, University of Basel, Basel, Switzerland
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4
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Bonavita R, Scerra G, Di Martino R, Nuzzo S, Polishchuk E, Di Gennaro M, Williams SV, Caporaso MG, Caiazza C, Polishchuk R, D’Agostino M, Fleming A, Renna M. The HSPB1-p62/SQSTM1 functional complex regulates the unconventional secretion and transcellular spreading of the HD-associated mutant huntingtin protein. Hum Mol Genet 2023; 32:2269-2291. [PMID: 36971475 PMCID: PMC10321397 DOI: 10.1093/hmg/ddad047] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 03/06/2023] [Accepted: 03/23/2023] [Indexed: 07/20/2023] Open
Abstract
Conformational diseases, such as Alzheimer, Parkinson and Huntington diseases, are part of a common class of neurological disorders characterized by the aggregation and progressive accumulation of proteins bearing aberrant conformations. Huntington disease (HD) has autosomal dominant inheritance and is caused by mutations leading to an abnormal expansion in the polyglutamine (polyQ) tract of the huntingtin (HTT) protein, leading to the formation of HTT inclusion bodies in neurons of affected patients. Interestingly, recent experimental evidence is challenging the conventional view by which the disease pathogenesis is solely a consequence of the intracellular accumulation of mutant protein aggregates. These studies reveal that transcellular transfer of mutated huntingtin protein is able to seed oligomers involving even the wild-type (WT) forms of the protein. To date, there is still no successful strategy to treat HD. Here, we describe a novel functional role for the HSPB1-p62/SQSTM1 complex, which acts as a cargo loading platform, allowing the unconventional secretion of mutant HTT by extracellular vesicles. HSPB1 interacts preferentially with polyQ-expanded HTT compared with the WT protein and affects its aggregation. Furthermore, HSPB1 levels correlate with the rate of mutant HTT secretion, which is controlled by the activity of the PI3K/AKT/mTOR signalling pathway. Finally, we show that these HTT-containing vesicular structures are biologically active and able to be internalized by recipient cells, therefore providing an additional mechanism to explain the prion-like spreading properties of mutant HTT. These findings might also have implications for the turn-over of other disease-associated, aggregation-prone proteins.
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Affiliation(s)
| | | | - R Di Martino
- Institute for Endocrinology and Experimental Oncology “G. Salvatore,” National Research Council, 80131 Naples, Italy
- Institute of Biochemistry and Cell Biology, National Research Council, 80131 Naples, Italy
| | - S Nuzzo
- IRCCS SYNLAB SDN, 80143 Naples, Italy
| | - E Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - M Di Gennaro
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - S V Williams
- Department of Physiology, Development and Neuroscience, University of Cambridge, CB2 3DY Cambridge, UK
| | - M G Caporaso
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - C Caiazza
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - R Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - M D’Agostino
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy
| | - A Fleming
- Department of Physiology, Development and Neuroscience, University of Cambridge, CB2 3DY Cambridge, UK
| | - M Renna
- To whom correspondence should be addressed at: Department of Molecular Medicine and Medical Biotechnologies, School of Medicine, University of Naples “Federico II”, Via S. Pansini, 5, Building 19, Corpi Bassi Sud (I floor), 80131 Naples, Italy. Tel: +39 081/7463623, Fax: +39 081-7463205;
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5
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Subramaniam S. Striatal Induction and Spread of the Huntington’s Disease Protein: A Novel Rhes Route. J Huntingtons Dis 2022; 11:281-290. [PMID: 35871361 PMCID: PMC9484121 DOI: 10.3233/jhd-220548] [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] [Indexed: 11/25/2022]
Abstract
The CAG/CAA expansion encoding polyQ huntingtin (mutant huntingtin [mHTT]) causes Huntington’s disease (HD), which is characterized by atrophy and loss of striatal medium spiny neurons (MSNs), which are preceded by neuropathological alterations in the cortex. Previous studies have shown that mHTT can spread in the brain, but the mechanisms involved in the stereotyped degeneration and dysfunction of the neurons from the striatum to the cortex remain unclear. In this study, we found that the mHTT expression initially restricted in the striatum later spread to the cortical regions in mouse brains. Such transmission was diminished in mice that lacked the striatal-enriched protein Ras-homolog enriched in the striatum (Rhes). Rhes restricted to MSNs was also found in the cortical layers of the brain, indicating a new transmission route for the Rhes protein to the brain. Mechanistically, Rhes promotes such transmission via a direct cell-to-cell contact mediated by tunneling nanotubes (TNTs), the membranous protrusions that enable the transfer of mHTT, Rhes, and other vesicular cargoes. These transmission patterns suggest that Rhes and mHTT are likely co-transported in the brain using TNT-like cell-to-cell contacts. On the basis of these new results, a perspective is presented in this review: Rhes may ignite the mHTT transmission from the striatum that may coincide with HD onset and disease progression through an anatomically connected striato-cortical retrograde route.
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Turos-Korgul L, Kolba MD, Chroscicki P, Zieminska A, Piwocka K. Tunneling Nanotubes Facilitate Intercellular Protein Transfer and Cell Networks Function. Front Cell Dev Biol 2022; 10:915117. [PMID: 35903550 PMCID: PMC9314668 DOI: 10.3389/fcell.2022.915117] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 06/20/2022] [Indexed: 11/24/2022] Open
Abstract
The past decade witnessed a huge interest in the communication machinery called tunneling nanotubes (TNTs) which is a novel, contact-dependent type of intercellular protein transfer (IPT). As the IPT phenomenon plays a particular role in the cross-talk between cells, including cancer cells as well as in the immune and nervous systems, it therefore participates in remodeling of the cellular networks. The following review focuses on the placing the role of tunneling nanotube-mediated protein transfer between distant cells. Firstly, we describe different screening methods used to study IPT including tunneling nanotubes. Further, we present various examples of TNT-mediated protein transfer in the immune system, cancer microenvironment and in the nervous system, with particular attention to the methods used to verify the transfer of individual proteins.
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7
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Narang P, Shah M, Beljanski V. Exosomal RNAs in diagnosis and therapies. Noncoding RNA Res 2022; 7:7-15. [PMID: 35087990 PMCID: PMC8777382 DOI: 10.1016/j.ncrna.2022.01.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 12/17/2022] Open
Abstract
The field of extracellular vesicles has been rapidly developing after it became evident that a defined subset of vesicles, called exosomes, can modulate several biological functions in distant cells and tissues. Exosomes range in a size from 40 to 160 nm in diameter, are released by majority of cells in our body, and carry molecules which reflect the cell of origin. The types of biomolecules packed, their respective purpose, and their impact on the physiological state of distinct cells and tissues should be understood to advance the using of exosomes as biomarkers of health and disease. Many of such physiological effects can be linked to exosomal RNA molecules which include both coding and non-coding RNAs. The biological role(s) of various exosomal RNAs have started being recognized after RNA sequencing methods became widely available which led to discovery of a variety of RNA molecules in exosomes and their roles in regulating of many biological processes are beginning to be unraveled. In present review, we outline and discuss recent progress in the elucidation of the various biological processes driven by exosomal RNA and their relevance for several major conditions including disorders of central nervous system, cardiovascular system, metabolism, cancer, and immune system. Furthermore, we also discuss potential use of exosomes as valuable therapeutics for tissue regeneration and for conditions resulting from excessive inflammation. While exosome research is still in its infancy, in-depth understanding of exosome formation, their biological effects, and specific cell-targeting will uncover how they can be used as disease biomarkers and therapeutics.
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Affiliation(s)
- Pranay Narang
- Department of Biological Sciences, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, Davie, Florida, United States
| | - Morish Shah
- Department of Public Health, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University, Davie, Florida, United States
| | - Vladimir Beljanski
- Department of Biological Sciences, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, Davie, Florida, United States
- Dr. Kiran C. Patel College of Allopathic Medicine, Nova Southeastern University, Davie, Florida, United States
- Cell Therapy Institute, Dr Kiran C. Patel College of Allopathic Medicine, Nova Southeastern University, Davie, Florida, United States
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8
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Kaur S, Verma H, Dhiman M, Tell G, Gigli GL, Janes F, Mantha AK. Brain Exosomes: Friend or Foe in Alzheimer's Disease? Mol Neurobiol 2021; 58:6610-6624. [PMID: 34595669 DOI: 10.1007/s12035-021-02547-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 08/23/2021] [Indexed: 01/18/2023]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease. It is known to be a multifactorial disease and several causes are associated with its occurrence as well as progression. However, the accumulation of amyloid beta (Aβ) is widely considered its major pathogenic hallmark. Additionally, neurofibrillary tangles (NFT), mitochondrial dysfunction, oxidative stress, and aging (cellular senescence) are considered as additional hits affecting the disease pathology. Several studies are now suggesting important role of inflammation in AD, which shifts our thought towards the brain's resident immune cells, microglia, and astrocytes; how they interact with neurons; and how these interactions are affected by intra and extracellular stressful factors. These interactions can be modulated by different mechanisms and pathways, in which exosomes could play an important role. Exosomes are multivesicular bodies secreted by nearly all types of cells. The exosomes secreted by glial cells or neurons affect the interactions and thus the physiology of these cells by transmitting miRNAs, proteins, and lipids. Exosomes can serve as a friend or foe to the neuron function, depending upon the carried signals. Exosomes, from the healthy microenvironment, may assist neuron function and health, whereas, from the stressed microenvironment, they carry oxidative and inflammatory signals to the neurons and thus prove detrimental to the neuronal function. Furthermore, exosomes can cross the blood-brain barrier (BBB), and from the blood plasma they can enter the brain cells and activate microglia and astrocytes. Exosomes can transport Aβ or Tau, cytokines, miRNAs between the cells, and alter the physiology of recipient cells. They can also assist in Aβ clearance and regulation of synaptic activity. The exosomes derived from different cells play different roles, and this field is still in its infancy stage. This review advocates exosomes' role as a friend or foe in neurodegenerative diseases, especially in the case of Alzheimer's disease.
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Affiliation(s)
- Sharanjot Kaur
- Department of Microbiology, School of Biological Sciences , Central University of Punjab, Bathinda, Punjab, India
| | - Harkomal Verma
- Department of Zoology, School of Biological Sciences, Central University of Punjab, Village Ghudda151 401, Punjab, Bathinda, India
| | - Monisha Dhiman
- Department of Microbiology, School of Biological Sciences , Central University of Punjab, Bathinda, Punjab, India
| | - Gianluca Tell
- Department of Medicine, University of Udine, Udine, Italy
| | - Gian Luigi Gigli
- Department of Medicine, University of Udine, Udine, Italy
- Clinical Neurology, Udine University Hospital, Udine, Italy
| | | | - Anil K Mantha
- Department of Zoology, School of Biological Sciences, Central University of Punjab, Village Ghudda151 401, Punjab, Bathinda, India.
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Kim C, Yousefian-Jazi A, Choi SH, Chang I, Lee J, Ryu H. Non-Cell Autonomous and Epigenetic Mechanisms of Huntington's Disease. Int J Mol Sci 2021; 22:12499. [PMID: 34830381 PMCID: PMC8617801 DOI: 10.3390/ijms222212499] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 02/06/2023] Open
Abstract
Huntington's disease (HD) is a rare neurodegenerative disorder caused by an expansion of CAG trinucleotide repeat located in the exon 1 of Huntingtin (HTT) gene in human chromosome 4. The HTT protein is ubiquitously expressed in the brain. Specifically, mutant HTT (mHTT) protein-mediated toxicity leads to a dramatic degeneration of the striatum among many regions of the brain. HD symptoms exhibit a major involuntary movement followed by cognitive and psychiatric dysfunctions. In this review, we address the conventional role of wild type HTT (wtHTT) and how mHTT protein disrupts the function of medium spiny neurons (MSNs). We also discuss how mHTT modulates epigenetic modifications and transcriptional pathways in MSNs. In addition, we define how non-cell autonomous pathways lead to damage and death of MSNs under HD pathological conditions. Lastly, we overview therapeutic approaches for HD. Together, understanding of precise neuropathological mechanisms of HD may improve therapeutic approaches to treat the onset and progression of HD.
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Affiliation(s)
- Chaebin Kim
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
| | - Ali Yousefian-Jazi
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
| | - Seung-Hye Choi
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
| | - Inyoung Chang
- Department of Biology, Boston University, Boston, MA 02215, USA;
| | - Junghee Lee
- Boston University Alzheimer’s Disease Research Center, Boston University, Boston, MA 02118, USA
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
- VA Boston Healthcare System, Boston, MA 02130, USA
| | - Hoon Ryu
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
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Jabłońska M, Grzelakowska K, Wiśniewski B, Mazur E, Leis K, Gałązka P. Pridopidine in the treatment of Huntington's disease. Rev Neurosci 2021; 31:441-451. [PMID: 32083454 DOI: 10.1515/revneuro-2019-0085] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 12/06/2019] [Indexed: 01/26/2023]
Abstract
Huntington's disease (HD) is a highly common inherited monogenic neurodegenerative disease, and the gene responsible for its development is located in the 4p16.3 chromosome. The product of that gene mutation is an abnormal huntingtin (Htt) protein that disrupts the neural conduction, thus leading to motor and cognitive disorders. The disease progresses to irreversible changes in the central nervous system (CNS). Although only a few drugs are available to symptomatic treatment, 'dopamine stabilizers' (as represented by the pridopidine) may be the new treatment options. The underlying causes of HD are dopaminergic conduction disorders. Initially, the disease is hyperkinetic (chorea) until it eventually reaches the hypokinetic phase. Studies confirmed a correlation between the amount of dopamine in the CNS and the stage of the disease. Pridopidine has the capacity to be a dopamine buffer, which could increase or decrease the dopamine content depending on the disease phase. A research carried out on animal models demonstrated the protective effect of pridopidine on nerve cells thanks to its ability to alter the cortical glutamatergic signaling through the N-methyl-D-aspartate (NMDA) receptors. Studies on dopamine stabilizers also reported that pridopidine has a 100-fold greater affinity for the sigma-1 receptor than for the D2 receptor. Disturbances in the activity of sigma-1 receptors occur in neurodegenerative diseases, including HD. Their interaction with pridopidine results in the neuroprotective effect, which is manifested as an increase in the plasticity of synaptic neurons and prevention of their atrophy within the striatum. To determine the effectiveness of pridopidine in the treatment of HD, large multicenter randomized studies such as HART, MermaiHD, and PRIDE-HD were carried out.
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Affiliation(s)
- Magdalena Jabłońska
- Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-090 Bydgoszcz, Poland
| | - Klaudyna Grzelakowska
- Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-090 Bydgoszcz, Poland
| | - Bartłomiej Wiśniewski
- Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-090 Bydgoszcz, Poland
| | - Ewelina Mazur
- Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-090 Bydgoszcz, Poland
| | - Kamil Leis
- Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-090 Bydgoszcz, Poland
| | - Przemysław Gałązka
- Department of General and Oncological Pediatric Surgery, Antoni Jurasz University Hospital No. 1 in Bydgoszcz, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-090 Bydgoszcz, Poland
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11
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Shedding a new light on Huntington's disease: how blood can both propagate and ameliorate disease pathology. Mol Psychiatry 2021; 26:5441-5463. [PMID: 32514103 DOI: 10.1038/s41380-020-0787-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 05/06/2020] [Accepted: 05/13/2020] [Indexed: 01/01/2023]
Abstract
Huntington's disease (HD) is a monogenic neurodegenerative disorder resulting from a mutation in the huntingtin gene. This leads to the expression of the mutant huntingtin protein (mHTT) which provokes pathological changes in both the central nervous system (CNS) and periphery. Accumulating evidence suggests that mHTT can spread between cells of the CNS but here, we explored the possibility that mHTT could also propagate and cause pathology via the bloodstream. For this, we used a parabiosis approach to join the circulatory systems of wild-type (WT) and zQ175 mice. After surgery, we observed mHTT in the plasma and circulating blood cells of WT mice and post-mortem analyses revealed the presence of mHTT aggregates in several organs including the liver, kidney, muscle and brain. The presence of mHTT in the brain was accompanied by vascular abnormalities, such as a reduction of Collagen IV signal intensity and altered vessel diameter in the striatum, and changes in expression of Glutamic acid decarboxylase 65/67 (GAD65-67) in the cortex. Conversely, we measured reduced pathology in zQ175 mice by decreased mitochondrial impairments in peripheral organs, restored vessel diameter in the cortex and improved expression of Dopamine- and cAMP-regulated phosphoprotein 32 (DARPP32) in striatal neurons. Collectively, these results demonstrate that circulating mHTT can disseminate disease, but importantly, that healthy blood can dilute pathology. These findings have significant implications for the development of therapies in HD.
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12
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Chuang CL, Demontis F. Systemic manifestation and contribution of peripheral tissues to Huntington's disease pathogenesis. Ageing Res Rev 2021; 69:101358. [PMID: 33979693 DOI: 10.1016/j.arr.2021.101358] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 03/23/2021] [Accepted: 05/07/2021] [Indexed: 12/11/2022]
Abstract
Huntington disease (HD) is an autosomal dominant neurodegenerative disease that is caused by expansion of cytosine/adenosine/guanine repeats in the huntingtin (HTT) gene, which leads to a toxic, aggregation-prone, mutant HTT-polyQ protein. Beyond the well-established mechanisms of HD progression in the central nervous system, growing evidence indicates that also peripheral tissues are affected in HD and that systemic signaling originating from peripheral tissues can influence the progression of HD in the brain. Herein, we review the systemic manifestation of HD in peripheral tissues, and the impact of systemic signaling on HD pathogenesis. Mutant HTT induces a body wasting syndrome (cachexia) primarily via its activity in skeletal muscle, bone, adipose tissue, and heart. Additional whole-organism effects induced by mutant HTT include decline in systemic metabolic homeostasis, which stems from derangement of pancreas, liver, gut, hypothalamic-pituitary-adrenal axis, and circadian functions. In addition to spreading via the bloodstream and a leaky blood brain barrier, HTT-polyQ may travel long distance via its uptake by neurons and its axonal transport from the peripheral to the central nervous system. Lastly, signaling factors that are produced and/or secreted in response to therapeutic interventions such as exercise or in response to mutant HTT activity in peripheral tissues may impact HD. In summary, these studies indicate that HD is a systemic disease that is influenced by intertissue signaling and by the action of pathogenic HTT in peripheral tissues. We propose that treatment strategies for HD should include the amelioration of HD symptoms in peripheral tissues. Moreover, harnessing signaling between peripheral tissues and the brain may provide a means for reducing HD progression in the central nervous system.
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Kuang X, Nunn K, Jiang J, Castellano P, Hardikar U, Horgan A, Kong J, Tan Z, Dai W. Structural insight into transmissive mutant huntingtin species by correlative light and electron microscopy and cryo-electron tomography. Biochem Biophys Res Commun 2021; 560:99-104. [PMID: 33984771 DOI: 10.1016/j.bbrc.2021.04.124] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 04/29/2021] [Indexed: 02/07/2023]
Abstract
Aggregates of mutant huntingtin (mHTT) containing an expanded polyglutamine (polyQ) tract are hallmarks of Huntington's Disease (HD). Studies have shown that mHTT can spread between cells, leading to the propagation of misfolded protein pathology. However, the structure of transmissive mHTT species, and the molecular mechanisms underlying their transmission remain unknown. Using correlative light and electron microscopy (CLEM) and cryo-electron tomography (cryo-ET), we identified two types of aggregation-prone granules in conditioned medium from PC12 cells expressing a mHTT N-terminal fragment: densities enclosed by extracellular vesicles (EVs), and uncoated, amorphous meshworks of heterogeneous oligomers that co-localize with clusters of EVs. In vitro assays confirmed that liposomes induce condensation of polyQ oligomers into higher-order assemblies, resembling the uncoated meshworks observed in PC12 conditioned medium. Our findings provide novel insights into formation and architecture of transmissive mHTT proteins, and highlight the potential role of EVs as both carriers and modulators of transmissive mHTT proteins.
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Affiliation(s)
- Xuyuan Kuang
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Department of Hyperbaric Oxygen, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Kyle Nunn
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Jennifer Jiang
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Paul Castellano
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Uttara Hardikar
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Arianna Horgan
- Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Joyce Kong
- Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Zhiqun Tan
- Department of Anatomy and Neurobiology, University of California Irvine School of Medicine, Irvine, CA, 29697, USA; Institute for Memory Impairment and Neurological Disorders, University of California-Irvine, Irvine, CA, 29697, USA.
| | - Wei Dai
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA; Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA.
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14
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Cordero Cervantes D, Zurzolo C. Peering into tunneling nanotubes-The path forward. EMBO J 2021; 40:e105789. [PMID: 33646572 PMCID: PMC8047439 DOI: 10.15252/embj.2020105789] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 10/21/2020] [Accepted: 01/15/2021] [Indexed: 12/19/2022] Open
Abstract
The identification of Tunneling Nanotubes (TNTs) and TNT-like structures signified a critical turning point in the field of cell-cell communication. With hypothesized roles in development and disease progression, TNTs' ability to transport biological cargo between distant cells has elevated these structures to a unique and privileged position among other mechanisms of intercellular communication. However, the field faces numerous challenges-some of the most pressing issues being the demonstration of TNTs in vivo and understanding how they form and function. Another stumbling block is represented by the vast disparity in structures classified as TNTs. In order to address this ambiguity, we propose a clear nomenclature and provide a comprehensive overview of the existing knowledge concerning TNTs. We also discuss their structure, formation-related pathways, biological function, as well as their proposed role in disease. Furthermore, we pinpoint gaps and dichotomies found across the field and highlight unexplored research avenues. Lastly, we review the methods employed to date and suggest the application of new technologies to better understand these elusive biological structures.
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Affiliation(s)
| | - Chiara Zurzolo
- Institut PasteurMembrane Traffic and PathogenesisParisFrance
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15
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Gong W, Pan W, He Y, Huang M, Zhang J, Gu Z, Zhang D, Yang Z, Qu J. Super-resolution imaging of the dynamic cleavage of intercellular tunneling nanotubes. FRONTIERS OF OPTOELECTRONICS 2020; 13:318-326. [PMID: 36641564 PMCID: PMC9743874 DOI: 10.1007/s12200-020-1068-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Accepted: 09/11/2020] [Indexed: 06/17/2023]
Abstract
As a new method of cell-cell communication, tunneling nanotubes (TNTs) play important roles in cell-cell signaling and mass exchanges. However, a lack of powerful tools to visualize dynamic TNTs with high temporal/spatial resolution restricts the exploration of their formation and cleavage, hindering the complete understanding of its mechanism. Herein, we present the first example of using stochastic optical reconstruction microscopy (STORM) to observe the tube-like structures of TNTs linking live cells with an easily prepared fluorescent dye. Because of this new imaging microscopy, the cleavage process of TNTs was observed with a high spatial resolution.
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Affiliation(s)
- Wanjun Gong
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Wenhui Pan
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Ying He
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Meina Huang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Jianguo Zhang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Zhenyu Gu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Dan Zhang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Zhigang Yang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
| | - Junle Qu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
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16
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Stress-Sensitive Protein Rac1 and Its Involvement in Neurodevelopmental Disorders. Neural Plast 2020; 2020:8894372. [PMID: 33299404 PMCID: PMC7707960 DOI: 10.1155/2020/8894372] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 11/01/2020] [Accepted: 11/12/2020] [Indexed: 02/07/2023] Open
Abstract
Ras-related C3 botulinum toxin substrate 1 (Rac1) is a small GTPase that is well known for its sensitivity to the environmental stress of a cell or an organism. It senses the external signals which are transmitted from membrane-bound receptors and induces downstream signaling cascades to exert its physiological functions. Rac1 is an important regulator of a variety of cellular processes, such as cytoskeletal organization, generation of oxidative products, and gene expression. In particular, Rac1 has a significant influence on certain brain functions like neuronal migration, synaptic plasticity, and memory formation via regulation of actin dynamics in neurons. Abnormal Rac1 expression and activity have been observed in multiple neurological diseases. Here, we review recent findings to delineate the role of Rac1 signaling in neurodevelopmental disorders associated with abnormal spine morphology, synaptogenesis, and synaptic plasticity. Moreover, certain novel inhibitors of Rac1 and related pathways are discussed as potential avenues toward future treatment for these diseases.
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17
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Tang BL. Trafficking Unconventionally via UPS. Cells 2020; 9:cells9092009. [PMID: 32882862 PMCID: PMC7564385 DOI: 10.3390/cells9092009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 09/01/2020] [Indexed: 11/24/2022] Open
Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore
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18
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Jamwal S, Elsworth JD, Rahi V, Kumar P. Gene therapy and immunotherapy as promising strategies to combat Huntington's disease-associated neurodegeneration: emphasis on recent updates and future perspectives. Expert Rev Neurother 2020; 20:1123-1141. [PMID: 32720531 DOI: 10.1080/14737175.2020.1801424] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Modulation of gene expression using gene therapy as well as modulation of immune activation using immunotherapy has attracted considerable attention as rapidly emerging potential therapeutic intervention for the treatment of HD. Several preclinical and clinical trials for gene-based therapy and immunotherapy/antibody-based have been conducted. AREAS COVERED This review focused on the potential use of gene therapy and immuno-based therapies to treat HD, including the current status, the rationale for these approaches as well as preclinical and clinical data supporting it. Growing knowledge of HD pathogenesis has resulted in the discovery of new therapeutic targets, some of which are now in clinical trials. Focus has been allocated to RNA and DNA-based gene therapies for the reduction of mutant huntingtin (mHTT), using Immuno/antibody-based therapies. EXPERT OPINION While safety and efficacy of gene therapy and immunotherapy has been well demonstrated for HD, therefore much focus has now been shifted to disease-modifying therapies. This review defines the current status and future directions of gene therapy and immunotherapies. The review summarizes by what means HD genetic root cause modification and functional restoration of mHtt protein could be achieved by using targeted multimodality gene therapy and immunotherapy to target intracellular and extracellular mHtt.
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Affiliation(s)
- Sumit Jamwal
- Department of Psychiatry, Yale University School of Medicine , New Haven, CT, USA
| | - John D Elsworth
- Department of Psychiatry, Yale University School of Medicine , New Haven, CT, USA
| | - Vikrant Rahi
- Department of Pharmaceutical Sciences and Technology, Maharaja Ranjit Singh Punjab Technical University , Bathinda, India
| | - Puneet Kumar
- Department of Pharmacology, School of Basic and Applied Sciences, Central University of Punjab , Bathinda, India
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19
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Bartl S, Oueslati A, Southwell AL, Siddu A, Parth M, David LS, Maxan A, Salhat N, Burkert M, Mairhofer A, Friedrich T, Pankevych H, Balazs K, Staffler G, Hayden MR, Cicchetti F, Smrzka OW. Inhibiting cellular uptake of mutant huntingtin using a monoclonal antibody: Implications for the treatment of Huntington's disease. Neurobiol Dis 2020; 141:104943. [PMID: 32407769 DOI: 10.1016/j.nbd.2020.104943] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/08/2020] [Accepted: 05/06/2020] [Indexed: 12/24/2022] Open
Abstract
Huntington's disease (HD) is caused by a highly polymorphic CAG trinucleotide expansion in the gene encoding for the huntingtin protein (HTT). The resulting mutant huntingtin protein (mutHTT) is ubiquitously expressed but also exhibits the ability to propagate from cell-to-cell to disseminate pathology; a property which may serve as a new therapeutic focus. Accordingly, we set out to develop a monoclonal antibody (mAB) targeting a particularly exposed region close to the aa586 caspase-6 cleavage site of the HTT protein. This monoclonal antibody, designated C6-17, effectively binds mutHTT and is able to deplete the protein from cell culture supernatants. Using cell-based assays, we demonstrate that extracellular secretion of mutHTT into cell culture media and its subsequent uptake in recipient HeLa cells can be almost entirely blocked by mAB C6-17. Immunohistochemical stainings of post-mortem HD brain tissue confirmed the specificity of mAB C6-17 to human mutHTT aggregates. These findings demonstrate that mAB C6-17 not only successfully engages with its target, mutHTT, but also inhibits cell uptake suggesting that this antibody could interfere with the pathological processes of mutHTT spreading in vivo.
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Affiliation(s)
| | - Abid Oueslati
- Université Laval/Centre de recherche du CHU, Québec, Canada
| | | | - Alberto Siddu
- Université Laval/Centre de recherche du CHU, Québec, Canada
| | | | | | | | | | | | | | | | | | | | | | | | | | - Oskar W Smrzka
- AFFiRiS AG, Vienna, Austria; Ablevia biotech GmbH, Vienna, Austria
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20
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Sameni S, Zhang R, Digman MA. The Phasor FLIM Method Reveals a Link Between a Change in Energy Metabolism and mHtt protein spread in Healthy Mammalian Cells when Co-cultured with Huntington Diseased Cells. Methods Appl Fluoresc 2020; 9. [PMID: 32235053 DOI: 10.1088/2050-6120/ab854d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 03/31/2020] [Indexed: 11/12/2022]
Abstract
Huntington Disease (HD) is a late-onset autosomal neurodegenerative disease characterized by the aggregations of mutant Huntingtin proteins (mHTT). A glutamine stretch (PolyQ) at the N-terminal of the Huntingtin protein is generated by the abnormal expansion of CAG trinucleotide repeats in exon 1 of the HTT gene. While the resulting polyQ aggregates are the predominate feature of HD , the intercellular spread of the expanded protein and the effect upon this transfer inside healthy cells have not yet fully understood. Here, we have employed the phasor Fluorescence Lifetime Imaging Microscopy (FLIM) method to measure NADH fluorescence lifetime change after the internalization of the PolyQ protein. Based on our analysis, we have found a significant decrease in the fraction of bound NADH in both cytoplasmic and nucleus regions when cells are co-cultured or when healthy cells uptake the supernatant containing polyQ proteins and aggregates. Overall, our FLIM study combined with confocal fluorescence imaging visualizes the absorption of the mutant Htt protein aggregates which results in a distinct NADH fluorescence lifetime between control cells and acceptor cells. These studies show, for the first time, the influence of how neighboring cells expressing the expanded Htt protein can regulate energy metabolism in healthy cells.
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Affiliation(s)
- Sara Sameni
- CNL, Salk Institute, La Jolla, California, UNITED STATES
| | - Run Zhang
- Surgery, University of California San Francisco, San Francisco, California, UNITED STATES
| | - Michelle A Digman
- Biomedical Engineering, University of California Irvine, University of California, Irvine, CA, United States, Irvine, California, UNITED STATES
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21
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Ochaba J, Fote G, Kachemov M, Thein S, Yeung SY, Lau AL, Hernandez S, Lim RG, Casale M, Neel MJ, Monuki ES, Reidling J, Housman DE, Thompson LM, Steffan JS. IKKβ slows Huntington's disease progression in R6/1 mice. Proc Natl Acad Sci U S A 2019; 116:10952-10961. [PMID: 31088970 PMCID: PMC6561205 DOI: 10.1073/pnas.1814246116] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Neuroinflammation is an important contributor to neuronal pathology and death in neurodegenerative diseases and neuronal injury. Therapeutic interventions blocking the activity of the inflammatory kinase IKKβ, a key regulator of neuroinflammatory pathways, is protective in several animal models of neurodegenerative disease and neuronal injury. In Huntington's disease (HD), however, significant questions exist as to the impact of blocking or diminishing the activity of IKKβ on HD pathology given its potential role in Huntingtin (HTT) degradation. In cell culture, IKKβ phosphorylates HTT serine (S) 13 and activates HTT degradation, a process that becomes impaired with polyQ expansion. To investigate the in vivo relationship of IKKβ to HTT S13 phosphorylation and HD progression, we crossed conditional tamoxifen-inducible IKKβ knockout mice with R6/1 HD mice. Behavioral assays in these mice showed a significant worsening of HD pathological phenotypes. The increased behavioral pathology correlated with reduced levels of endogenous mouse full-length phospho-S13 HTT, supporting the importance of IKKβ in the phosphorylation of HTT S13 in vivo. Notably, many striatal autophagy genes were up-regulated in HD vs. control mice; however, IKKβ knockout partially reduced this up-regulation in HD, increased striatal neurodegeneration, and enhanced an activated microglial response. We propose that IKKβ is protective in striatal neurons early in HD progression via phosphorylation of HTT S13. As IKKβ is also required for up-regulation of some autophagy genes and HTT is a scaffold for selective autophagy, IKKβ may influence autophagy through multiple mechanisms to maintain healthy striatal function, thereby reducing neuronal degeneration to slow HD onset.
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Affiliation(s)
- Joseph Ochaba
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
| | - Gianna Fote
- Department of Biological Chemistry, University of California, Irvine, CA 92697
| | - Marketta Kachemov
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
| | - Soe Thein
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697
| | - Sylvia Y Yeung
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697
| | - Alice L Lau
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697
| | - Sarah Hernandez
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
- Sue and Bill Gross Stem Cell Center, University of California, Irvine, CA 92697
| | - Ryan G Lim
- Department of Biological Chemistry, University of California, Irvine, CA 92697
- Sue and Bill Gross Stem Cell Center, University of California, Irvine, CA 92697
| | - Malcolm Casale
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
| | - Michael J Neel
- Department of Pathology & Laboratory Medicine, University of California, Irvine, CA 92697
| | - Edwin S Monuki
- Department of Pathology & Laboratory Medicine, University of California, Irvine, CA 92697
| | - Jack Reidling
- Institute of Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - David E Housman
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139;
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Leslie M Thompson
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
- Department of Biological Chemistry, University of California, Irvine, CA 92697
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697
- Sue and Bill Gross Stem Cell Center, University of California, Irvine, CA 92697
- Institute of Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Joan S Steffan
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697;
- Institute of Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
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