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Liu L, Huang JS, Han C, Zhang GX, Xu XY, Shen Y, Li J, Jiang HY, Lin ZC, Xiong N, Wang T. Induced Pluripotent Stem Cells in Huntington's Disease: Disease Modeling and the Potential for Cell-Based Therapy. Mol Neurobiol 2015; 53:6698-6708. [PMID: 26659595 DOI: 10.1007/s12035-015-9601-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 12/01/2015] [Indexed: 12/31/2022]
Abstract
Huntington's disease (HD) is an incurable neurodegenerative disorder that is characterized by motor dysfunction, cognitive impairment, and behavioral abnormalities. It is an autosomal dominant disorder caused by a CAG repeat expansion in the huntingtin gene, resulting in progressive neuronal loss predominately in the striatum and cortex. Despite the discovery of the causative gene in 1993, the exact mechanisms underlying HD pathogenesis have yet to be elucidated. Treatments that slow or halt the disease process are currently unavailable. Recent advances in induced pluripotent stem cell (iPSC) technologies have transformed our ability to study disease in human neural cells. Here, we firstly review the progress made to model HD in vitro using patient-derived iPSCs, which reveal unique insights into illuminating molecular mechanisms and provide a novel human cell-based platform for drug discovery. We then highlight the promises and challenges for pluripotent stem cells that might be used as a therapeutic source for cell replacement therapy of the lost neurons in HD brains.
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Affiliation(s)
- Ling Liu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jin-Sha Huang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Chao Han
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Guo-Xin Zhang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiao-Yun Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yan Shen
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jie Li
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hai-Yang Jiang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhi-Cheng Lin
- Department of Psychiatry, Harvard Medical School; Division of Alcohol and Drug Abuse, and Mailman Neuroscience Research Center, McLean Hospital, Belmont, MA, USA
| | - Nian Xiong
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Tao Wang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
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Purine nucleosides in neuroregeneration and neuroprotection. Neuropharmacology 2015; 104:226-42. [PMID: 26577017 DOI: 10.1016/j.neuropharm.2015.11.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 11/05/2015] [Accepted: 11/06/2015] [Indexed: 12/20/2022]
Abstract
In the present review, we stress the importance of the purine nucleosides, adenosine and guanosine, in protecting the nervous system, both centrally and peripherally, via activation of their receptors and intracellular signalling mechanisms. A most novel part of the review focus on the mechanisms of neuronal regeneration that are targeted by nucleosides, including a recently identified action of adenosine on axonal growth and microtubule dynamics. Discussion on the role of the purine nucleosides transversally with the most established neurotrophic factors, e.g. brain derived neurotrophic factor (BDNF), glial derived neurotrophic factor (GDNF), is also focused considering the intimate relationship between some adenosine receptors, as is the case of the A2A receptors, and receptors for neurotrophins. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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Crotti A, Glass CK. The choreography of neuroinflammation in Huntington's disease. Trends Immunol 2015; 36:364-73. [PMID: 26001312 PMCID: PMC4786070 DOI: 10.1016/j.it.2015.04.007] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 04/19/2015] [Accepted: 04/19/2015] [Indexed: 01/01/2023]
Abstract
Currently, the concept of 'neuroinflammation' includes inflammation associated with neurodegenerative diseases, in which there is little or no infiltration of blood-derived immune cells into the brain. The roles of brain-resident and peripheral immune cells in these inflammatory settings are poorly understood, and it is unclear whether neuroinflammation results from immune reaction to neuronal dysfunction/degeneration, and/or represents cell-autonomous phenotypes of dysfunctional immune cells. Here, we review recent studies examining these questions in the context of Huntington's disease (HD), where mutant Huntingtin (HTT) is expressed in both neurons and glia. Insights into the cellular and molecular mechanisms underlying neuroinflammation in HD may provide a better understanding of inflammation in more complex neurodegenerative disorders, and of the contribution of the neuroinflammatory component to neurodegenerative disease pathogenesis.
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Affiliation(s)
| | - Christopher K Glass
- Department of Cellular and Molecular Medicine, University of California San Diego, CA, USA; Department of Medicine, University of California San Diego, CA, USA.
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Saftig P, Bovolenta P. Proteases at work: cues for understanding neural development and degeneration. Front Mol Neurosci 2015; 8:13. [PMID: 25999813 PMCID: PMC4419857 DOI: 10.3389/fnmol.2015.00013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 04/21/2015] [Indexed: 12/19/2022] Open
Abstract
Proteolytical processing of membrane bound molecules is a fundamental mechanism for the degradation of these proteins as well as for controlling cell-to-cell communication, which is at the basis of tissue development and homeostasis. Members of families of metalloproteinases and intra-membrane proteases are major effectors of these events. A recent workshop in Baeza, Spain, was devoted to discuss how this mechanism coordinates brain development and how its dysfunction leads to brain pathologies. Herein we summarize the findings presented during this workshop, which illuminate the role of metalloproteinases, including matrix metalloproteinase, A Disintegrin and Metalloproteinase-proteases and intra-membrane proteases, in the regulation of neurogenesis, axon guidance, and synaptogenesis as well as in neurodegeneration. Indeed, there is increasing evidence that proteolysis at the membrane is directly linked to neuropathologies such as Alzheimer Disease and autism spectrum or prion disorders. These proteolytic events are tightly regulated and we are just at the beginning of understanding how these processes could be exploited to design therapeutic treatments aimed at alleviating psychiatric and neurodegenerative pathologies.
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Affiliation(s)
- Paul Saftig
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, Kiel Germany
| | - Paola Bovolenta
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Madrid Spain ; Centro de Investigación Biomédica en Red de Enfermedades Raras, Madrid Spain
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Kreiner G. Compensatory mechanisms in genetic models of neurodegeneration: are the mice better than humans? Front Cell Neurosci 2015; 9:56. [PMID: 25798086 PMCID: PMC4351629 DOI: 10.3389/fncel.2015.00056] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 02/06/2015] [Indexed: 01/08/2023] Open
Abstract
Neurodegenerative diseases are one of the main causes of mental and physical disabilities. Neurodegeneration has been estimated to begin many years before the first clinical symptoms manifest, and even a prompt diagnosis at this stage provides very little advantage for a more effective treatment as the currently available pharmacotherapies are based on disease symptomatology. The etiology of the majority of neurodegenerative diseases remains unknown, and even for those diseases caused by identified genetic mutations, the direct pathways from gene alteration to final cell death have not yet been fully elucidated. Advancements in genetic engineering have provided many transgenic mice that are used as an alternative to pharmacological models of neurodegenerative diseases. Surprisingly, even the models reiterating the same causative mutations do not fully recapitulate the inevitable neuronal loss, and some fail to even show phenotypic alterations, which suggests the possible existence of compensatory mechanisms. A better evaluation of these mechanisms may not only help us to explain why neurodegenerative diseases are mostly late-onset disorders in humans but may also provide new markers and targets for novel strategies designed to extend neuronal function and survival. The aim of this mini-review is to draw attention to this under-explored field in which investigations may reasonably contribute to unveiling hidden reserves in the organism.
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Affiliation(s)
- Grzegorz Kreiner
- Department of Brain Biochemistry, Institute of Pharmacology, Polish Academy of Sciences Kraków, Poland
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Differential effects of delayed aging on phenotype and striatal pathology in a murine model of Huntington disease. J Neurosci 2015; 34:15658-68. [PMID: 25411494 DOI: 10.1523/jneurosci.1830-14.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The common neurodegenerative syndromes exhibit age-related incidence, and many Mendelian neurodegenerative diseases exhibit age-related penetrance. Mutations slowing aging retard age related pathologies. To assess whether delayed aging retards the effects of a mutant allele causing a Huntington's disease (HD)-like syndrome, we generated compound mutant mice, placing a dominant HD knock-in polyglutamine allele onto the slow-aging Snell dwarf genotype. The Snell genotype did not affect mutant huntingtin protein expression. Bigenic and control mice were evaluated prospectively from 10 to 100 weeks of age. Adult HD knock-in allele mice lost weight progressively with weight loss blunted significantly in male bigenic HD knock-in/Snell dwarf mice. Impaired balance beam performance developed significantly more slowly in bigenic HD knock-in/Snell dwarf mice. Striatal dopamine receptor expression was diminished significantly and similarly in all HD-like mice, regardless of the Snell genotype. Striatal neuronal intranuclear inclusion burden was similar between HD knock-in mice with and without the Snell genotype, whereas nigral neuropil aggregates were diminished in bigenic HD knock-in/Snell dwarf mice. Compared with control mice, Snell dwarf mice exhibited differences in regional benzodiazepine and cannabinoid receptor binding site expression. These results indicate that delaying aging delayed behavioral decline with little effect on the development of striatal pathology in this model of HD but may have altered synaptic pathology. These results indicate that mutations prolonging lifespan in mice delay onset of significant phenotypic features of this model and also demonstrate dissociation between striatal pathology and a commonly used behavioral measure of disease burden in HD models.
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Striatal long noncoding RNA Abhd11os is neuroprotective against an N-terminal fragment of mutant huntingtin in vivo. Neurobiol Aging 2014; 36:1601.e7-16. [PMID: 25619660 DOI: 10.1016/j.neurobiolaging.2014.11.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 10/28/2014] [Accepted: 11/25/2014] [Indexed: 12/26/2022]
Abstract
A large number of gene products that are enriched in the striatum have ill-defined functions, although they may have key roles in age-dependent neurodegenerative diseases affecting the striatum, especially Huntington disease (HD). In the present study, we focused on Abhd11os, (called ABHD11-AS1 in human) which is a putative long noncoding RNA (lncRNA) whose expression is enriched in the mouse striatum. We confirm that despite the presence of 2 small open reading frames (ORFs) in its sequence, Abhd11os is not translated into a detectable peptide in living cells. We demonstrate that Abhd11os levels are markedly reduced in different mouse models of HD. We performed in vivo experiments in mice using lentiviral vectors encoding either Abhd11os or a small hairpin RNA targeting Abhd11os. Results show that Abhd11os overexpression produces neuroprotection against an N-terminal fragment of mutant huntingtin, whereas Abhd11os knockdown is protoxic. These novel results indicate that the loss lncRNA Abhd11os likely contribute to striatal vulnerability in HD. Our study emphasizes that lncRNA may play crucial roles in neurodegenerative diseases.
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Francelle L, Galvan L, Gaillard MC, Guillermier M, Houitte D, Bonvento G, Petit F, Jan C, Dufour N, Hantraye P, Elalouf JM, De Chaldée M, Déglon N, Brouillet E. Loss of the thyroid hormone-binding protein Crym renders striatal neurons more vulnerable to mutant huntingtin in Huntington's disease. Hum Mol Genet 2014; 24:1563-73. [PMID: 25398949 PMCID: PMC4381754 DOI: 10.1093/hmg/ddu571] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The mechanisms underlying preferential atrophy of the striatum in Huntington's disease (HD) are unknown. One hypothesis is that a set of gene products preferentially expressed in the striatum could determine the particular vulnerability of this brain region to mutant huntingtin (mHtt). Here, we studied the striatal protein µ-crystallin (Crym). Crym is the NADPH-dependent p38 cytosolic T3-binding protein (p38CTBP), a key regulator of thyroid hormone (TH) T3 (3,5,3'-triiodo-l-thyronine) transportation. It has been also recently identified as the enzyme that reduces the sulfur-containing cyclic ketimines, which are potential neurotransmitters. Here, we confirm the preferential expression of the Crym protein in the rodent and macaque striatum. Crym expression was found to be higher in the macaque caudate than in the putamen. Expression of Crym was reduced in the BACHD and Knock-in 140CAG mouse models of HD before onset of striatal atrophy. We show that overexpression of Crym in striatal medium-size spiny neurons using a lentiviral-based strategy in mice is neuroprotective against the neurotoxicity of an N-terminal fragment of mHtt in vivo. Thus, reduction of Crym expression in HD could render striatal neurons more susceptible to mHtt suggesting that Crym may be a key determinant of the vulnerability of the striatum. In addition our work points to Crym as a potential molecular link between striatal degeneration and the THs deregulation reported in HD patients.
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Affiliation(s)
- Laetitia Francelle
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Laurie Galvan
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Marie-Claude Gaillard
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Martine Guillermier
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Diane Houitte
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Gilles Bonvento
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Fanny Petit
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Caroline Jan
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Noëlle Dufour
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Philippe Hantraye
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France
| | - Jean-Marc Elalouf
- CEA, iBiTecS, F-91191 Gif-sur-Yvette Cedex, France, CNRS, FRE 3377, F-91191 Gif-sur-Yvette Cedex, France, Université Paris-Sud, FRE 3377, F-91191 Gif-sur-Yvette Cedex, France
| | - Michel De Chaldée
- CEA, iBiTecS, F-91191 Gif-sur-Yvette Cedex, France, CNRS, FRE 3377, F-91191 Gif-sur-Yvette Cedex, France, Université Paris-Sud, FRE 3377, F-91191 Gif-sur-Yvette Cedex, France
| | - Nicole Déglon
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France, Laboratory of Cellular and Molecular Neurotherapies, Department of Clinical Neurociences, Lausanne University Hospital, Lausanne, Switzerland
| | - Emmanuel Brouillet
- CEA, DSV, I²BM, Molecular Imaging Research Center (MIRCen), F-92265 Fontenay-aux-Roses, France, Neurodegenerative Diseases Laboratory, CNRS CEA URA 2210, F-92265 Fontenay-aux-Roses, France,
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Francelle L, Galvan L, Brouillet E. Possible involvement of self-defense mechanisms in the preferential vulnerability of the striatum in Huntington's disease. Front Cell Neurosci 2014; 8:295. [PMID: 25309327 PMCID: PMC4176035 DOI: 10.3389/fncel.2014.00295] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 09/03/2014] [Indexed: 01/01/2023] Open
Abstract
HD is caused by a mutation in the huntingtin gene that consists in a CAG repeat expansion translated into an abnormal poly-glutamine (polyQ) tract in the huntingtin (Htt) protein. The most striking neuropathological finding in HD is the atrophy of the striatum. The regional expression of mutant Htt (mHtt) is ubiquitous in the brain and cannot explain by itself the preferential vulnerability of the striatum in HD. mHtt has been shown to produce an early defect in transcription, through direct alteration of the function of key regulators of transcription and in addition, more indirectly, as a result of compensatory responses to cellular stress. In this review, we focus on gene products that are preferentially expressed in the striatum and have down- or up-regulated expression in HD and, as such, may play a crucial role in the susceptibility of the striatum to mHtt. Many of these striatal gene products are for a vast majority down-regulated and more rarely increased in HD. Recent research shows that some of these striatal markers have a pro-survival/neuroprotective role in neurons (e.g., MSK1, A2A, and CB1 receptors) whereas others enhance the susceptibility of striatal neurons to mHtt (e.g., Rhes, RGS2, D2 receptors). The down-regulation of these latter proteins may be considered as a potential self-defense mechanism to slow degeneration. For a majority of the striatal gene products that have been identified so far, their function in the striatum is unknown and their modifying effects on mHtt toxicity remain to be experimentally addressed. Focusing on these striatal markers may contribute to a better understanding of HD pathogenesis, and possibly the identification of novel therapeutic targets.
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Affiliation(s)
- Laetitia Francelle
- Neurodegenerative Disease Laboratory, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction des Sciences du Vivant, Institut d'Imagerie BioMédicale, Molecular Imaging Research Center Fontenay-aux-Roses, France ; Centre National de la Recherche Scientifique - Commissariat à l'Énergie Atomique et aux Énergies Alternatives Unité de Recherche Associée 2210 Fontenay-aux-Roses, France
| | - Laurie Galvan
- Neurodegenerative Disease Laboratory, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction des Sciences du Vivant, Institut d'Imagerie BioMédicale, Molecular Imaging Research Center Fontenay-aux-Roses, France ; Centre National de la Recherche Scientifique - Commissariat à l'Énergie Atomique et aux Énergies Alternatives Unité de Recherche Associée 2210 Fontenay-aux-Roses, France ; Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, Brain Research Institute, David Geffen School of Medicine, University of California Los Angeles Los Angeles, CA, USA
| | - Emmanuel Brouillet
- Neurodegenerative Disease Laboratory, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction des Sciences du Vivant, Institut d'Imagerie BioMédicale, Molecular Imaging Research Center Fontenay-aux-Roses, France ; Centre National de la Recherche Scientifique - Commissariat à l'Énergie Atomique et aux Énergies Alternatives Unité de Recherche Associée 2210 Fontenay-aux-Roses, France
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Scheuing L, Chiu CT, Liao HM, Linares GR, Chuang DM. Preclinical and clinical investigations of mood stabilizers for Huntington's disease: what have we learned? Int J Biol Sci 2014; 10:1024-38. [PMID: 25285035 PMCID: PMC4183923 DOI: 10.7150/ijbs.9898] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 07/08/2014] [Indexed: 12/20/2022] Open
Abstract
Huntington's disease (HD) is a lethal, autosomal dominant neurodegenerative disorder caused by CAG repeat expansions at exon 1 of the huntingtin (Htt) gene, which encodes for a mutant huntingtin protein (mHtt). Prominent symptoms of HD include motor dysfunction, characterized by chorea; psychiatric disturbances such as mood and personality changes; and cognitive decline that may lead to dementia. Pathologically multiple complex processes and pathways are involved in the development of HD, including selective loss of neurons in the striatum and cortex, dysregulation of cellular autophagy, mitochondrial dysfunction, decreased neurotrophic and growth factor levels, and aberrant regulation of gene expression and epigenetic patterns. No cure for HD presently exists, nor are there drugs that can halt the progression of this devastating disease. Therefore, the need to discover neuroprotective modalities to combat HD is critical. In basic and preclinical studies using cellular and animal HD models, the mood stabilizers lithium and valproic acid (VPA) have shown multiple beneficial effects, including behavioral and motor improvement, enhanced neuroprotection, and lifespan extension. Recent studies in transgenic HD mice support the notion that combined lithium/VPA treatment is more effective than treatment with either drug alone. In humans, several clinical studies of HD patients found that lithium treatment improved mood, and that VPA treatment both stabilized mood and moderately reduced chorea. In contrast, other studies observed that the hallmark features of HD were unaffected by treatment with either lithium or VPA. The current review discusses preclinical and clinical investigations of the beneficial effects of lithium and VPA on HD pathophysiology.
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Affiliation(s)
- Lisa Scheuing
- Molecular Neurobiology Section, National Institute of Mental Health, National Institutes of Health, 10 Center Drive MSC 1363, Bethesda, MD 20892-1363, USA
| | - Chi-Tso Chiu
- Molecular Neurobiology Section, National Institute of Mental Health, National Institutes of Health, 10 Center Drive MSC 1363, Bethesda, MD 20892-1363, USA
| | - Hsiao-Mei Liao
- Molecular Neurobiology Section, National Institute of Mental Health, National Institutes of Health, 10 Center Drive MSC 1363, Bethesda, MD 20892-1363, USA
| | - Gabriel R Linares
- Molecular Neurobiology Section, National Institute of Mental Health, National Institutes of Health, 10 Center Drive MSC 1363, Bethesda, MD 20892-1363, USA
| | - De-Maw Chuang
- Molecular Neurobiology Section, National Institute of Mental Health, National Institutes of Health, 10 Center Drive MSC 1363, Bethesda, MD 20892-1363, USA
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