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Ormsby AR, Cox D, Daly J, Priest D, Hinde E, Hatters DM. Nascent mutant Huntingtin exon 1 chains do not stall on ribosomes during translation but aggregates do recruit machinery involved in ribosome quality control and RNA. PLoS One 2020; 15:e0233583. [PMID: 32735619 PMCID: PMC7394408 DOI: 10.1371/journal.pone.0233583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 07/13/2020] [Indexed: 11/18/2022] Open
Abstract
Mutations that cause Huntington’s Disease involve a polyglutamine (polyQ) sequence expansion beyond 35 repeats in exon 1 of Huntingtin. Intracellular inclusion bodies of mutant Huntingtin protein are a key feature of Huntington’s disease brain pathology. We previously showed that in cell culture the formation of inclusions involved the assembly of disordered structures of mHtt exon 1 fragments (Httex1) and they were enriched with translational machinery when first formed. We hypothesized that nascent mutant Httex1 chains co-aggregate during translation by phase separation into liquid-like disordered aggregates and then convert to more rigid, amyloid structures. Here we further examined the mechanisms of inclusion assembly in a human epithelial kidney (AD293) cell culture model. We found mHttex1 did not appear to stall translation of its own nascent chain, or at best was marginal. We also found the inclusions appeared to recruit low levels of RNA but there was no difference in enrichment between early formed and mature inclusions. Proteins involved in translation or ribosome quality control were co-recruited to the inclusions (Ltn1 Rack1) compared to a protein not anticipated to be involved (NACAD), but there was no major specificity of enrichment in the early formed inclusions compared to mature inclusions. Furthermore, we observed co-aggregation with other proteins previously identified in inclusions, including Upf1 and chaperone-like proteins Sgta and Hspb1, which also suppressed aggregation at high co-expression levels. The newly formed inclusions also contained immobile mHttex1 molecules which points to the disordered aggregates being mechanically rigid prior to amyloid formation. Collectively our findings show little evidence that inclusion assembly arises by a discrete clustering of stalled nascent chains and associated quality control machinery. Instead, the machinery appear to be recruited continuously, or secondarily, to the nucleation of inclusion formation.
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Affiliation(s)
- Angelique R. Ormsby
- Department of Biochemistry and Molecular Biology; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC, Australia
| | - Dezerae Cox
- Department of Biochemistry and Molecular Biology; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC, Australia
| | - James Daly
- Department of Biochemistry and Molecular Biology; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC, Australia
| | - David Priest
- Department of Biochemistry and Molecular Biology; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC, Australia
| | - Elizabeth Hinde
- Department of Biochemistry and Molecular Biology; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC, Australia
| | - Danny M. Hatters
- Department of Biochemistry and Molecular Biology; and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC, Australia
- * E-mail:
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Sava V, Fihurka O, Khvorova A, Sanchez-Ramos J. Enriched chitosan nanoparticles loaded with siRNA are effective in lowering Huntington's disease gene expression following intranasal administration. Nanomedicine 2020; 24:102119. [PMID: 31666200 PMCID: PMC7098382 DOI: 10.1016/j.nano.2019.102119] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/09/2019] [Accepted: 10/15/2019] [Indexed: 02/07/2023]
Abstract
Therapies to lower gene expression in brain disease currently require chronic administration into the cerebrospinal fluid (CSF) by intrathecal infusions or direct intracerebral injections. Though well-tolerated in the short-term, this approach is not tenable for a life-time of administration. Nose-to-brain delivery of enriched chitosan-based nanoparticles loaded with anti-HTT siRNA was studied in a transgenic YAC128 mouse model of Huntington's Disease (HD). A series of chitosan-based nanoparticle (NP) formulations encapsulating anti-HTT small interfering RNA (siRNA) was designed to protect the payload from degradation "en route" to the target. Factors to improve production of effective nanocarriers of anti-HTT siRNA were identified and tested in a YAC128 mouse model of Huntington's disease. Four formulations of nanocarriers were identified to be effective in lowering HTT mRNA expression by at least 50%. Intranasal administration of nanoparticles carrying siRNA is a promising therapeutic alternative for safe and effective lowering of mutant HTT expression.
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Affiliation(s)
- Vasyl Sava
- Department of Neurology, University of South Florida, Tampa, FL
| | - Oksana Fihurka
- Department of Neurology, University of South Florida, Tampa, FL
| | - Anastasia Khvorova
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
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Webb TE. Eukaryotic (translation) initiation factor 4A (eIF4A) inhibition may be used to treat Huntington's disease by decreasing the expression of huntingtin. Med Hypotheses 2018; 114:28. [PMID: 29602458 DOI: 10.1016/j.mehy.2017.10.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 10/17/2017] [Accepted: 10/27/2017] [Indexed: 11/18/2022]
Affiliation(s)
- Thomas E Webb
- Guy's and St Thomas' NHS Trust, St Thomas' Hospital, London SE1 7EH, United Kingdom.
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Hamilton J, Brustovetsky T, Brustovetsky N. Oxidative metabolism and Ca 2+ handling in striatal mitochondria from YAC128 mice, a model of Huntington's disease. Neurochem Int 2017; 109:24-33. [PMID: 28062223 PMCID: PMC5495615 DOI: 10.1016/j.neuint.2017.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 12/29/2016] [Accepted: 01/02/2017] [Indexed: 01/30/2023]
Abstract
The mechanisms implicated in the pathology of Huntington's disease (HD) remain not completely understood, although dysfunction of mitochondrial oxidative metabolism and Ca2+ handling have been suggested as contributing factors. However, in our previous studies with mitochondria isolated from the whole brains of HD mice, we found no evidence for defects in mitochondrial respiration and Ca2+ handling. In the present study, we used the YAC128 mouse model of HD to evaluate the effect of mHtt on respiratory activity and Ca2+ uptake capacity of mitochondria isolated from the striatum, the most vulnerable brain region in HD. Isolated, Percoll-gradient purified striatal mitochondria from YAC128 mice were free of cytosolic and ER contaminations, but retained attached mHtt. Both nonsynaptic and synaptic striatal mitochondria isolated from early symptomatic 2-month-old YAC128 mice had similar respiratory rates and Ca2+ uptake capacities compared with mitochondria from wild-type FVB/NJ mice. Consistent with the lack of difference in mitochondrial respiration, we found that the expression of several nuclear-encoded proteins in striatal mitochondria was similar between wild-type and YAC128 mice. Taken together, our data demonstrate that mHtt does not alter respiration and Ca2+ uptake capacity in striatal mitochondria isolated from YAC128 mice, suggesting that respiratory defect and Ca2+ uptake deficiency most likely do not contribute to striatal pathology associated with HD.
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Affiliation(s)
- James Hamilton
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Tatiana Brustovetsky
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Nickolay Brustovetsky
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States; Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN, United States.
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Shekhar S, Vatsa N, Kumar V, Singh BK, Jamal I, Sharma A, Jana NR. Topoisomerase 1 inhibitor topotecan delays the disease progression in a mouse model of Huntington's disease. Hum Mol Genet 2017; 26:420-429. [PMID: 28007908 DOI: 10.1093/hmg/ddw398] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 11/17/2016] [Indexed: 11/14/2022] Open
Abstract
Huntington's disease (HD) is a dominantly inherited progressive neurodegenerative disorder caused by the accumulation of polyglutamine expanded mutant huntingtin as inclusion bodies primarily in the brain. After the discovery of the HD gene, considerable progress has been made in understanding the disease pathogenesis and multiple drug targets have been identified, even though currently there is no effective therapy. Here, we demonstrate that the treatment of topotecan, a brain-penetrating topoisomerase 1 inhibitor, to HD transgenic mouse considerably improved its motor behavioural abnormalities along with a significant extension of lifespan. Improvement of behavioural deficits are accompanied with the significant rescue of their progressively decreased body weight, brain weight and striatal volume. Interestingly, topotecan treatment also significantly reduced insoluble mutant huntingtin load in the HD mouse brain. Finally, we show that topotecan treatment to HD mouse not only inhibits the expression of transgenic mutant huntingtin, but also at the same time induces the expression of Ube3a, an ubiquitin ligase linked to the clearance of mutant huntingtin. These findings suggest that topotecan could be a potential therapeutic molecule to delay the progression of HD.
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Shin A, Shin B, Shin JW, Kim KH, Atwal RS, Hope JM, Gillis T, Leszyk JD, Shaffer SA, Lee R, Kwak S, MacDonald ME, Gusella JF, Seong IS, Lee JM. Novel allele-specific quantification methods reveal no effects of adult onset CAG repeats on HTT mRNA and protein levels. Hum Mol Genet 2017; 26:1258-1267. [PMID: 28165127 PMCID: PMC6075029 DOI: 10.1093/hmg/ddx033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 12/08/2016] [Accepted: 01/19/2017] [Indexed: 01/26/2023] Open
Abstract
Huntington's disease (HD) reflects dominant consequences of a CAG repeat expansion mutation in HTT. Expanded CAG repeat size is the primary determinant of age at onset and age at death in HD. Although HD pathogenesis is driven by the expanded CAG repeat, whether the mutation influences the expression levels of mRNA and protein from the disease allele is not clear due to the lack of sensitive allele-specific quantification methods and the presence of confounding factors. To determine the impact of CAG expansion at the molecular level, we have developed novel allele-specific HTT mRNA and protein quantification methods based on principles of multiplex ligation-dependent probe amplification and targeted MS/MS parallel reaction monitoring, respectively. These assays, exhibiting high levels of specificity and sensitivity, were designed to distinguish allelic products based upon expressed polymorphic variants in HTT, including rs149 109 767. To control for other cis-haplotype variations, we applied allele-specific quantification assays to a panel of HD lymphoblastoid cell lines, each carrying the major European disease haplotype (i.e. hap.01) on the mutant chromosome. We found that steady state levels of HTT mRNA and protein were not associated with expanded CAG repeat length. Rather, the products of mutant and normal alleles, both mRNA and protein, were balanced, thereby arguing that a cis-regulatory effect of the expanded CAG repeat is not a critical component of the underlying mechanism of HD. These robust allele-specific assays could prove valuable for monitoring the impact of allele-specific gene silencing strategies currently being explored as therapeutic interventions in HD.
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Affiliation(s)
- Aram Shin
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Baehyun Shin
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jun Wan Shin
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Kyung-Hee Kim
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Ranjit S. Atwal
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jennifer M. Hope
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Tammy Gillis
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - John D. Leszyk
- Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Scott A. Shaffer
- Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Ramee Lee
- CHDI Foundation, Princeton, NJ 08540, USA
| | - Seung Kwak
- CHDI Foundation, Princeton, NJ 08540, USA
| | - Marcy E. MacDonald
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Medical and Population Genetics Program, The Broad Institute of M.I.T. and Harvard, Cambridge, MA 02142, USA
| | - James F. Gusella
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Medical and Population Genetics Program, The Broad Institute of M.I.T. and Harvard, Cambridge, MA 02142, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Ihn Sik Seong
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jong-Min Lee
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Medical and Population Genetics Program, The Broad Institute of M.I.T. and Harvard, Cambridge, MA 02142, USA
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Ament SA, Pearl JR, Grindeland A, St. Claire J, Earls JC, Kovalenko M, Gillis T, Mysore J, Gusella JF, Lee JM, Kwak S, Howland D, Lee MY, Baxter D, Scherler K, Wang K, Geman D, Carroll JB, MacDonald ME, Carlson G, Wheeler VC, Price ND, Hood LE. High resolution time-course mapping of early transcriptomic, molecular and cellular phenotypes in Huntington's disease CAG knock-in mice across multiple genetic backgrounds. Hum Mol Genet 2017; 26:913-922. [PMID: 28334820 PMCID: PMC6075528 DOI: 10.1093/hmg/ddx006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 12/09/2016] [Accepted: 01/03/2017] [Indexed: 01/11/2023] Open
Abstract
Huntington's disease is a dominantly inherited neurodegenerative disease caused by the expansion of a CAG repeat in the HTT gene. In addition to the length of the CAG expansion, factors such as genetic background have been shown to contribute to the age at onset of neurological symptoms. A central challenge in understanding the disease progression that leads from the HD mutation to massive cell death in the striatum is the ability to characterize the subtle and early functional consequences of the CAG expansion longitudinally. We used dense time course sampling between 4 and 20 postnatal weeks to characterize early transcriptomic, molecular and cellular phenotypes in the striatum of six distinct knock-in mouse models of the HD mutation. We studied the effects of the HttQ111 allele on the C57BL/6J, CD-1, FVB/NCr1, and 129S2/SvPasCrl genetic backgrounds, and of two additional alleles, HttQ92 and HttQ50, on the C57BL/6J background. We describe the emergence of a transcriptomic signature in HttQ111/+ mice involving hundreds of differentially expressed genes and changes in diverse molecular pathways. We also show that this time course spanned the onset of mutant huntingtin nuclear localization phenotypes and somatic CAG-length instability in the striatum. Genetic background strongly influenced the magnitude and age at onset of these effects. This work provides a foundation for understanding the earliest transcriptional and molecular changes contributing to HD pathogenesis.
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Affiliation(s)
- Seth A. Ament
- Institute for Systems Biology, Seattle, WA, USA
- Institute for Genome Sciences and Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jocelynn R. Pearl
- Institute for Systems Biology, Seattle, WA, USA
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA, USA
| | | | - Jason St. Claire
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - John C. Earls
- Institute for Systems Biology, Seattle, WA, USA
- Department of Computer Science, University of Washington, Seattle, WA, USA
| | - Marina Kovalenko
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Tammy Gillis
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Jayalakshmi Mysore
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - James F. Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Jong-Min Lee
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Seung Kwak
- CHDI Management/CHDI Foundation, Princeton, NJ, USA
| | | | | | | | | | - Kai Wang
- Institute for Systems Biology, Seattle, WA, USA
| | - Donald Geman
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, USA
| | - Jeffrey B. Carroll
- Behavioral Neuroscience Program, Department of Psychology, Western Washington University, Bellingham, WA, USA
| | - Marcy E. MacDonald
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
| | | | - Vanessa C. Wheeler
- Center for Human Genetic Research, Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA
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Rué L, Bañez-Coronel M, Creus-Muncunill J, Giralt A, Alcalá-Vida R, Mentxaka G, Kagerbauer B, Zomeño-Abellán MT, Aranda Z, Venturi V, Pérez-Navarro E, Estivill X, Martí E. Targeting CAG repeat RNAs reduces Huntington's disease phenotype independently of huntingtin levels. J Clin Invest 2016; 126:4319-4330. [PMID: 27721240 DOI: 10.1172/jci83185] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/08/2016] [Indexed: 12/11/2022] Open
Abstract
Huntington's disease (HD) is a polyglutamine disorder caused by a CAG expansion in the Huntingtin (HTT) gene exon 1. This expansion encodes a mutant protein whose abnormal function is traditionally associated with HD pathogenesis; however, recent evidence has also linked HD pathogenesis to RNA stable hairpins formed by the mutant HTT expansion. Here, we have shown that a locked nucleic acid-modified antisense oligonucleotide complementary to the CAG repeat (LNA-CTG) preferentially binds to mutant HTT without affecting HTT mRNA or protein levels. LNA-CTGs produced rapid and sustained improvement of motor deficits in an R6/2 mouse HD model that was paralleled by persistent binding of LNA-CTG to the expanded HTT exon 1 transgene. Motor improvement was accompanied by a pronounced recovery in the levels of several striatal neuronal markers severely impaired in R6/2 mice. Furthermore, in R6/2 mice, LNA-CTG blocked several pathogenic mechanisms caused by expanded CAG RNA, including small RNA toxicity and decreased Rn45s expression levels. These results suggest that LNA-CTGs promote neuroprotection by blocking the detrimental activity of CAG repeats within HTT mRNA. The present data emphasize the relevance of expanded CAG RNA to HD pathogenesis, indicate that inhibition of HTT expression is not required to reverse motor deficits, and further suggest a therapeutic potential for LNA-CTG in polyglutamine disorders.
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Miller JRC, Lo KK, Andre R, Hensman Moss DJ, Träger U, Stone TC, Jones L, Holmans P, Plagnol V, Tabrizi SJ. RNA-Seq of Huntington's disease patient myeloid cells reveals innate transcriptional dysregulation associated with proinflammatory pathway activation. Hum Mol Genet 2016; 25:2893-2904. [PMID: 27170315 PMCID: PMC5181590 DOI: 10.1093/hmg/ddw142] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/03/2016] [Accepted: 05/03/2016] [Indexed: 12/21/2022] Open
Abstract
Innate immune activation beyond the central nervous system is emerging as a vital component of the pathogenesis of neurodegeneration. Huntington's disease (HD) is a fatal neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene. The systemic innate immune system is thought to act as a modifier of disease progression; however, the molecular mechanisms remain only partially understood. Here we use RNA-sequencing to perform whole transcriptome analysis of primary monocytes from thirty manifest HD patients and thirty-three control subjects, cultured with and without a proinflammatory stimulus. In contrast with previous studies that have required stimulation to elicit phenotypic abnormalities, we demonstrate significant transcriptional differences in HD monocytes in their basal, unstimulated state. This includes previously undetected increased resting expression of genes encoding numerous proinflammatory cytokines, such as IL6 Further pathway analysis revealed widespread resting enrichment of proinflammatory functional gene sets, while upstream regulator analysis coupled with Western blotting suggests that abnormal basal activation of the NFĸB pathway plays a key role in mediating these transcriptional changes. That HD myeloid cells have a proinflammatory phenotype in the absence of stimulation is consistent with a priming effect of mutant huntingtin, whereby basal dysfunction leads to an exaggerated inflammatory response once a stimulus is encountered. These data advance our understanding of mutant huntingtin pathogenesis, establish resting myeloid cells as a key source of HD immune dysfunction, and further demonstrate the importance of systemic immunity in the potential treatment of HD and the wider study of neurodegeneration.
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Affiliation(s)
- James R C Miller
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Kitty K Lo
- UCL Genetics Institute, University College London, London, WC1E 6BT, UK
| | - Ralph Andre
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Davina J Hensman Moss
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Ulrike Träger
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Timothy C Stone
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Lesley Jones
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Peter Holmans
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Vincent Plagnol
- UCL Genetics Institute, University College London, London, WC1E 6BT, UK
| | - Sarah J Tabrizi
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
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