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Nittari G, Roy P, Martinelli I, Bellitto V, Tomassoni D, Traini E, Tayebati SK, Amenta F. Rodent Models of Huntington's Disease: An Overview. Biomedicines 2023; 11:3331. [PMID: 38137552 PMCID: PMC10741199 DOI: 10.3390/biomedicines11123331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
Huntington's disease (HD) is an autosomal-dominant inherited neurological disorder caused by a genetic mutation in the IT15 gene. This neurodegenerative disorder is caused by a polyglutamine repeat expansion mutation in the widely expressed huntingtin (HTT) protein. HD is characterized by the degeneration of basal ganglia neurons and progressive cell death in intrinsic neurons of the striatum, accompanied by dementia and involuntary abnormal choreiform movements. Animal models have been extensively studied and have proven to be extremely valuable for therapeutic target evaluations. They reveal the hallmark of the age-dependent formation of aggregates or inclusions consisting of misfolded proteins. Animal models of HD have provided a therapeutic strategy to treat HD by suppressing mutant HTT (mHTT). Transgenic animal models have significantly increased our understanding of the molecular processes and pathophysiological mechanisms underlying the HD behavioral phenotype. Since effective therapies to cure or interrupt the course of the disease are not yet available, clinical research will have to make use of reliable animal models. This paper reviews the main studies of rodents as HD animal models, highlighting the neurological and behavioral differences between them. The choice of an animal model depends on the specific aspect of the disease to be investigated. Toxin-based models can still be useful, but most experimental hypotheses depend on success in a genetic model, whose choice is determined by the experimental question. There are many animal models showing similar HD symptoms or pathologies. They include chemical-induced HDs and genetic HDs, where cell-free and cell culture, lower organisms (such as yeast, Drosophila, C. elegans, zebrafish), rodents (mice, rats), and non-human primates are involved. These models provide accessible systems to study molecular pathogenesis and test potential treatments. For developing more effective pharmacological treatments, better animal models must be available and used to evaluate the efficacy of drugs.
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Affiliation(s)
- Giulio Nittari
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
| | - Proshanta Roy
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
| | - Ilenia Martinelli
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
| | - Vincenzo Bellitto
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
| | - Daniele Tomassoni
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile III da Varano, 62032 Camerino, Italy;
| | - Enea Traini
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
| | - Seyed Khosrow Tayebati
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
| | - Francesco Amenta
- School of Medicinal and Health Products Sciences, University of Camerino, Via Madonna Delle Carceri, 9, 62032 Camerino, Italy; (G.N.); (P.R.); (I.M.); (V.B.); (E.T.); (S.K.T.)
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Reed AL, Mitchell W, Alexandrescu AT, Alder NN. Interactions of amyloidogenic proteins with mitochondrial protein import machinery in aging-related neurodegenerative diseases. Front Physiol 2023; 14:1263420. [PMID: 38028797 PMCID: PMC10652799 DOI: 10.3389/fphys.2023.1263420] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 10/02/2023] [Indexed: 12/01/2023] Open
Abstract
Most mitochondrial proteins are targeted to the organelle by N-terminal mitochondrial targeting sequences (MTSs, or "presequences") that are recognized by the import machinery and subsequently cleaved to yield the mature protein. MTSs do not have conserved amino acid compositions, but share common physicochemical properties, including the ability to form amphipathic α-helical structures enriched with basic and hydrophobic residues on alternating faces. The lack of strict sequence conservation implies that some polypeptides can be mistargeted to mitochondria, especially under cellular stress. The pathogenic accumulation of proteins within mitochondria is implicated in many aging-related neurodegenerative diseases, including Alzheimer's, Parkinson's, and Huntington's diseases. Mechanistically, these diseases may originate in part from mitochondrial interactions with amyloid-β precursor protein (APP) or its cleavage product amyloid-β (Aβ), α-synuclein (α-syn), and mutant forms of huntingtin (mHtt), respectively, that are mediated in part through their associations with the mitochondrial protein import machinery. Emerging evidence suggests that these amyloidogenic proteins may present cryptic targeting signals that act as MTS mimetics and can be recognized by mitochondrial import receptors and transported into different mitochondrial compartments. Accumulation of these mistargeted proteins could overwhelm the import machinery and its associated quality control mechanisms, thereby contributing to neurological disease progression. Alternatively, the uptake of amyloidogenic proteins into mitochondria may be part of a protein quality control mechanism for clearance of cytotoxic proteins. Here we review the pathomechanisms of these diseases as they relate to mitochondrial protein import and effects on mitochondrial function, what features of APP/Aβ, α-syn and mHtt make them suitable substrates for the import machinery, and how this information can be leveraged for the development of therapeutic interventions.
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Affiliation(s)
- Ashley L. Reed
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
| | - Wayne Mitchell
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Andrei T. Alexandrescu
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
| | - Nathan N. Alder
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
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Kriachkov VA, Gotmanova NN, Tashlitsky VN, Bacheva AV. Brain-Derived 11S Regulator (PA28αβ) Promotes Proteasomal Hydrolysis of Elongated Oligoglutamine-Containing Peptides. Int J Mol Sci 2023; 24:13275. [PMID: 37686081 PMCID: PMC10487437 DOI: 10.3390/ijms241713275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/08/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023] Open
Abstract
Proteins with extended polyglutamine regions are associated with several neurodegenerative disorders, including Huntington's disease. Intracellular proteolytic processing of these proteins is not well understood. In particular, it is unclear whether long polyglutamine fragments resulting from the proteolysis of these proteins can be potentially cleaved by the proteasome. Here, we studied the susceptibility of the glutamine-glutamine bond to proteolysis by the proteasome using oligoglutamine-containing peptides with a fluorophore/quencher pair. We found that the addition of the 11S proteasomal regulator (also known as PA28) significantly accelerated the hydrolysis of oligoglutamine-containing peptides by the 20S proteasome. Unexpectedly, a similar effect was observed for the 26S proteasome in the presence of the 11S regulator. LC/MS data revealed that the hydrolysis of our peptides with both 20S and 26S proteasomes leads to N-terminal fragments containing two or three glutamine residues and that the hydrolysis site does not change after the addition of the 11S regulator. This was confirmed by the docking experiment, which shows that the preferred hydrolysis site is located after the second/third glutamine residue. Inhibitory analysis revealed that trypsin-like specificity is mainly responsible for the proteasomal hydrolysis of the glutamine-glutamine bond. Together, our results indicate that both 20S and 26S proteasomes are capable of degrading the N-terminal part of oligoglutamine fragments, while the 11S regulator significantly accelerates the hydrolysis without changing its specificity. This data suggests that proteasome activity may be enhanced in relation to polyglutamine substrates present in neurons in the early stages of polyglutamine disorders.
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Affiliation(s)
- Viacheslav A. Kriachkov
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC 3010, Australia;
| | - Natalia N. Gotmanova
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (N.N.G.); (V.N.T.)
| | - Vadim N. Tashlitsky
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (N.N.G.); (V.N.T.)
| | - Anna V. Bacheva
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia; (N.N.G.); (V.N.T.)
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White A, McGlone A, Gomez-Pastor R. Protein Kinase CK2 and Its Potential Role as a Therapeutic Target in Huntington's Disease. Biomedicines 2022; 10:1979. [PMID: 36009526 PMCID: PMC9406209 DOI: 10.3390/biomedicines10081979] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/10/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
Huntington's Disease (HD) is a devastating neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the HTT gene, for which no disease modifying therapies are currently available. Much of the recent research has focused on developing therapies to directly lower HTT expression, and while promising, these therapies have presented several challenges regarding administration and efficacy. Another promising therapeutic approach is the modulation of HTT post-translational modifications (PTMs) that are dysregulated in disease and have shown to play a key role in HTT toxicity. Among all PTMs, modulation of HTT phosphorylation has been proposed as an attractive therapeutic option due to the possibility of orally administering specific kinase effectors. One of the kinases described to participate in HTT phosphorylation is Protein Kinase CK2. CK2 has recently emerged as a target for the treatment of several neurological and psychiatric disorders, although its role in HD remains controversial. While pharmacological studies in vitro inhibiting CK2 resulted in reduced HTT phosphorylation and increased toxicity, genetic approaches in mouse models of HD have provided beneficial effects. In this review we discuss potential therapeutic approaches related to the manipulation of HTT-PTMs with special emphasis on the role of CK2 as a therapeutic target in HD.
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Affiliation(s)
| | | | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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Jahanshahi A, Boonstra JT, Alosaimi F, Ozsoy O, Michielse S, Temel Y. Hidden brain atrophy in ultra-high-field MR images in a transgenic rat model of Huntington's disease. BRAIN DISORDERS 2022. [DOI: 10.1016/j.dscb.2022.100039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Nuclear and cytoplasmic huntingtin inclusions exhibit distinct biochemical composition, interactome and ultrastructural properties. Nat Commun 2021; 12:6579. [PMID: 34772920 PMCID: PMC8589980 DOI: 10.1038/s41467-021-26684-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/11/2021] [Indexed: 12/20/2022] Open
Abstract
Despite the strong evidence linking the aggregation of the Huntingtin protein (Htt) to the pathogenesis of Huntington's disease (HD), the mechanisms underlying Htt aggregation and neurodegeneration remain poorly understood. Herein, we investigated the ultrastructural properties and protein composition of Htt cytoplasmic and nuclear inclusions in mammalian cells and primary neurons overexpressing mutant exon1 of the Htt protein. Our findings provide unique insight into the ultrastructural properties of cytoplasmic and nuclear Htt inclusions and their mechanisms of formation. We show that Htt inclusion formation and maturation are complex processes that, although initially driven by polyQ-dependent Htt aggregation, also involve the polyQ and PRD domain-dependent sequestration of lipids and cytoplasmic and cytoskeletal proteins related to HD dysregulated pathways; the recruitment and accumulation of remodeled or dysfunctional membranous organelles, and the impairment of the protein quality control and degradation machinery. We also show that nuclear and cytoplasmic Htt inclusions exhibit distinct biochemical compositions and ultrastructural properties, suggesting different mechanisms of aggregation and toxicity.
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Schulze-Krebs A, Canneva F, Stemick J, Plank AC, Harrer J, Bates GP, Aeschlimann D, Steffan JS, von Hörsten S. Transglutaminase 6 Is Colocalized and Interacts with Mutant Huntingtin in Huntington Disease Rodent Animal Models. Int J Mol Sci 2021; 22:8914. [PMID: 34445621 PMCID: PMC8396294 DOI: 10.3390/ijms22168914] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/09/2021] [Accepted: 08/11/2021] [Indexed: 01/07/2023] Open
Abstract
Mammalian transglutaminases (TGs) catalyze calcium-dependent irreversible posttranslational modifications of proteins and their enzymatic activities contribute to the pathogenesis of several human neurodegenerative diseases. Although different transglutaminases are found in many different tissues, the TG6 isoform is mostly expressed in the CNS. The present study was embarked on/undertaken to investigate expression, distribution and activity of transglutaminases in Huntington disease transgenic rodent models, with a focus on analyzing the involvement of TG6 in the age- and genotype-specific pathological features relating to disease progression in HD transgenic mice and a tgHD transgenic rat model using biochemical, histological and functional assays. Our results demonstrate the physical interaction between TG6 and (mutant) huntingtin by co-immunoprecipitation analysis and the contribution of its enzymatic activity for the total aggregate load in SH-SY5Y cells. In addition, we identify that TG6 expression and activity are especially abundant in the olfactory tubercle and piriform cortex, the regions displaying the highest amount of mHTT aggregates in transgenic rodent models of HD. Furthermore, mHTT aggregates were colocalized within TG6-positive cells. These findings point towards a role of TG6 in disease pathogenesis via mHTT aggregate formation.
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Affiliation(s)
- Anja Schulze-Krebs
- Experimental Therapy, Preclinical Experimental Center, University Hospital Erlangen (UKEr), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (F.C.); (A.-C.P.); (J.H.); (S.v.H.)
| | - Fabio Canneva
- Experimental Therapy, Preclinical Experimental Center, University Hospital Erlangen (UKEr), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (F.C.); (A.-C.P.); (J.H.); (S.v.H.)
| | - Judith Stemick
- Department of Molecular Neurology, University Hospital Erlangen (UKEr), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany;
| | - Anne-Christine Plank
- Experimental Therapy, Preclinical Experimental Center, University Hospital Erlangen (UKEr), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (F.C.); (A.-C.P.); (J.H.); (S.v.H.)
| | - Julia Harrer
- Experimental Therapy, Preclinical Experimental Center, University Hospital Erlangen (UKEr), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (F.C.); (A.-C.P.); (J.H.); (S.v.H.)
| | - Gillian P. Bates
- Huntington’s Disease Centre, Department of Neurodegenerative Disease and UK Dementia Research Institute at UCL, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
| | - Daniel Aeschlimann
- Matrix Biology and Tissue Repair Research Unit, College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK;
| | - Joan S. Steffan
- Institute of Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697, USA;
- Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697, USA
| | - Stephan von Hörsten
- Experimental Therapy, Preclinical Experimental Center, University Hospital Erlangen (UKEr), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (F.C.); (A.-C.P.); (J.H.); (S.v.H.)
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Sanders M, Petrasch-Parwez E, Habbes HW, Düring MV, Förster E. Postnatal Developmental Expression Profile Classifies the Indusium Griseum as a Distinct Subfield of the Hippocampal Formation. Front Cell Dev Biol 2021; 8:615571. [PMID: 33511122 PMCID: PMC7835525 DOI: 10.3389/fcell.2020.615571] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/07/2020] [Indexed: 11/13/2022] Open
Abstract
The indusium griseum (IG) is a cortical structure overlying the corpus callosum along its anterior–posterior extent. It has been classified either as a vestige of the hippocampus or as an extension of the dentate gyrus via the fasciola cinerea, but its attribution to a specific hippocampal subregion is still under debate. To specify the identity of IG neurons more precisely, we investigated the spatiotemporal expression of calbindin, secretagogin, Necab2, PCP4, and Prox1 in the postnatal mouse IG, fasciola cinerea, and hippocampus. We identified the calcium-binding protein Necab2 as a first reliable marker for the IG and fasciola cinerea throughout postnatal development into adulthood. In contrast, calbindin, secretagogin, and PCP4 were expressed each with a different individual time course during maturation, and at no time point, IG or fasciola cinerea principal neurons expressed Prox1, a transcription factor known to define dentate granule cell fate. Concordantly, in a transgenic mouse line expressing enhanced green fluorescent protein (eGFP) in dentate granule cells, neurons of IG and fasciola cinerea were eGFP-negative. Our findings preclude that IG neurons represent dentate granule cells, as earlier hypothesized, and strongly support the view that the IG is an own hippocampal subfield composed of a distinct neuronal population.
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Affiliation(s)
- Marie Sanders
- Department of Neuroanatomy and Molecular Brain Research, Ruhr-University Bochum, Bochum, Germany
| | | | - Hans-Werner Habbes
- Department of Neuroanatomy and Molecular Brain Research, Ruhr-University Bochum, Bochum, Germany
| | - Monika V Düring
- Department of Neuroanatomy and Molecular Brain Research, Ruhr-University Bochum, Bochum, Germany
| | - Eckart Förster
- Department of Neuroanatomy and Molecular Brain Research, Ruhr-University Bochum, Bochum, Germany
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Investigating the Structure of Neurotoxic Protein Aggregates Inside Cells. Trends Cell Biol 2020; 30:951-966. [PMID: 32981805 DOI: 10.1016/j.tcb.2020.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/13/2020] [Accepted: 08/17/2020] [Indexed: 12/22/2022]
Abstract
Neurodegenerative diseases affect the lives of millions of people across the world, being particularly prevalent in the aging population. Despite huge research efforts, conclusive insights into the disease mechanisms are still lacking. Therefore, therapeutic strategies are limited to symptomatic treatments. A common histopathological hallmark of many neurodegenerative diseases is the presence of large pathognomonic protein aggregates, but their role in the disease pathology is unclear and subject to controversy. Here, we discuss imaging methods allowing investigation of these structures within their cellular environment: conventional electron microscopy (EM), super-resolution light microscopy (SR-LM), and cryo-electron tomography (cryo-ET). Multidisciplinary approaches are key for understanding neurodegenerative diseases and may contribute to the development of effective treatments. For simplicity, we focus on huntingtin aggregates, characteristic of Huntington's disease.
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Lateralization of increased density of Iba1-immunopositive microglial cells in the anterior midcingulate cortex of schizophrenia and bipolar disorder. Eur Arch Psychiatry Clin Neurosci 2020; 270:819-828. [PMID: 32062729 PMCID: PMC8510942 DOI: 10.1007/s00406-020-01107-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 02/03/2020] [Indexed: 12/27/2022]
Abstract
There is increasing evidence from genetic, biochemical, pharmacological, neuroimaging and post-mortem studies that immunological dysregulation plays a crucial role in the pathogenesis of psychoses. The involvement of microglia in schizophrenia and bipolar disorder (BD) has remained controversial, however, since results from various post-mortem studies are still inconclusive. Here, we analyzed the estimated density of microglia of age-matched individuals with schizophrenia (n = 17), BD (n = 13), and non-psychiatric control subjects (n = 17) in the anterior midcingulate cortex (aMCC), a brain area putatively involved in the pathogenesis of psychoses, using ionized calcium binding adaptor molecule 1 (Iba1)-immunohistochemistry. The microglial cells displayed a homogenously distributed Iba1-staining pattern in the aMCC with slightly varying activation states in all three groups. The estimated microglial densities did not differ significantly between individuals with schizophrenia, BD and control subjects. Remarkably, when both hemispheres were investigated separately within the three groups, the density was significantly lateralized towards the right aMCC in schizophrenia (p = 0.01) and-even more evident-in BD subjects (p = 0.008). This left-right lateralization was not observed in the control group (p = 0.52). Of note, microglial density was significantly lower in BD individuals who did not commit suicide compared with BD individuals who died from suicide (p = 0.002). This difference was not observed between individuals with BD who committed suicide and controls. The results, tentatively interpreted, suggest a hitherto unknown increased lateralization of microglial density to the right hemisphere in both psychiatric groups. If confirmed in independent samples, lateralization should be considered in all post-mortem studies on microglia. Density differences between suicide and non-suicide individuals needs further elucidation.
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FGF2 and dual agonist of NCAM and FGF receptor 1, Enreptin, rescue neurite outgrowth loss in hippocampal neurons expressing mutated huntingtin proteins. J Neural Transm (Vienna) 2019; 126:1493-1500. [PMID: 31501979 DOI: 10.1007/s00702-019-02073-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 08/30/2019] [Indexed: 10/26/2022]
Abstract
In the present study, we developed an in vitro model of Huntington disease (HD) by transfecting primary rat hippocampal neurons with plasmids coding for m-htt exon 1 with different number of CAG repeats (18, 50 and 115) and demonstrated the influence of the length of polyQ sequence on neurite elongation. We found that exogenously applied FGF2 significantly rescued the m-htt-induced loss of neurite outgrowth. Moreover, the Enreptin peptide, an FGFR1 and NCAM dual agonist, had a similar neuritogenic effect to FGF2 in clinically relevant m-htt 50Q-expressing neurons. This study has developed an in vitro model of primary hippocampal neurons transfected with m-htt-coding vectors that is a powerful tool to study m-htt-related effects on neuronal placticity.
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Schreiber S, Petrasch-Parwez E, Porrmann-Kelterbaum E, Förster E, Epplen JT, Gerding WM. Neurodegeneration in the olfactory bulb and olfactory deficits in the Ccdc66 -/- mouse model for retinal degeneration. IBRO Rep 2018; 5:43-53. [PMID: 30211337 PMCID: PMC6132079 DOI: 10.1016/j.ibror.2018.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 08/23/2018] [Indexed: 12/12/2022] Open
Abstract
The Ccdc66-deficient (Ccdc66 -/-) mouse model exhibits slow progressive retinal degeneration. It is unclear whether CCDC66 protein also plays a role in the wildtype (WT; Ccdc66 +/+) mouse brain and whether the lack of Ccdc66 gene expression in the Ccdc66 -/- mouse brain may result in morphological and behavioral alterations. CCDC66 protein expression in different brain regions of the adult WT mouse and in whole brain during postnatal development was quantified by SDS-PAGE and Western blot. Ccdc66 reporter gene expression was visualized by X-gal staining. Selected brain regions were further analyzed by light and electron microscopy. In order to correlate anatomical with behavioral data, an olfactory habituation/dishabituation test was performed. CCDC66 protein was expressed throughout the early postnatal development in the WT mouse brain. In adult mice, the main olfactory bulb exhibited high CCDC66 protein levels comparable to the expression in the retina. Additionally, the Ccdc66 -/- mouse brain showed robust Ccdc66 reporter gene expression especially in adult olfactory bulb glomeruli, the olfactory nerve layer and the olfactory epithelium. Degeneration was detected in the Ccdc66 -/- olfactory bulb glomeruli at advanced age. This degeneration was also reflected in behavioral alterations; compared to the WT, Ccdc66 -/- mice spent significantly less time sniffing at the initial presentation of unknown, neutral odors and barely responded to social odors. Ccdc66 -/- mice develop substantial olfactory nerve fiber degeneration and alteration of olfaction-related behavior at advanced age. Thus, the Ccdc66 -/- mouse model for retinal degeneration adds the possibility to study mechanisms of central nervous system degeneration.
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Key Words
- AG, astroglia
- CTX, cortex
- Ccdc66
- Ccdc66 +/+, WT, wildtype
- Ccdc66 -/-, Ccdc66-deficient
- De, dendrite
- EPL, external plexiform layer
- GAPDH, glyceraldehyde-3-phosphate dehydrogenase
- GL, glomerular layer
- IPL, internal plexiform layer
- M, mitochondrion
- ML, mitral cell layer
- MOB, main olfactory bulb
- Mouse model
- Neurodegeneration
- OE, olfactory epithelium
- ONF, olfactory nerve fibers
- ONL, olfactory nerve layer
- ORN, olfactory receptor neuron(s)
- Olfactory bulb
- P, postnatal day
- PBS, phosphate-buffered saline
- PG, periglomerular cells
- RIPA, radioimmunoprecipitation assay
- RMS, rostral migratory stream
- RP, retinitis pigmentosa
- Retinitis pigmentosa
- SC, supporting cell
- SEZ, subependymal zone
- SVZ, subventricular zone
- gPRA, generalized progressive retinal atrophy
- ioD, integrated optic density
- m, month/s
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Affiliation(s)
- Sabrina Schreiber
- Department of Human Genetics, Ruhr-University, 44780 Bochum, Germany
| | | | | | - Eckart Förster
- Department of Neuroanatomy and Molecular Brain Research, Ruhr-University, 44780 Bochum, Germany
| | - Jörg T. Epplen
- Department of Human Genetics, Ruhr-University, 44780 Bochum, Germany
- Department of Biochemistry and Molecular Medicine, University of Witten-Herdecke, ZBAF, 58453 Witten, Germany
| | - Wanda M. Gerding
- Department of Human Genetics, Ruhr-University, 44780 Bochum, Germany
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Genetic Rodent Models of Huntington Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1049:29-57. [DOI: 10.1007/978-3-319-71779-1_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Plank AC, Canneva F, Raber KA, Urbach YK, Dobner J, Puchades M, Bjaalie JG, Gillmann C, Bäuerle T, Riess O, Nguyen HHP, von Hörsten S. Early Alterations in Operant Performance and Prominent Huntingtin Aggregation in a Congenic F344 Rat Line of the Classical CAG n51trunc Model of Huntington Disease. Front Neurosci 2018; 12:11. [PMID: 29422836 PMCID: PMC5788972 DOI: 10.3389/fnins.2018.00011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/08/2018] [Indexed: 11/17/2022] Open
Abstract
The transgenic rat model of Huntington disease expressing a fragment of mutant HTT (tgHD rat) has been thoroughly characterized and reproduces hallmark symptoms of human adult-onset HD. Pursuing the optimization of this model for evaluation of translational therapeutic approaches, the F344 inbred rat strain was considered as advantageous genetic background for the expression of the HD transgenic construct. In the present study, a novel congenic line of the SPRDtgHD transgenic model of HD, carrying 51 CAG repeats, was generated on the F344 rat genetic background. To assess the behavioral phenotype, classical assays investigating motor function, emotion, and sensorimotor gating were applied, along with automated screening of metabolic and activity parameters as well as operant conditioning tasks. The neuropathological phenotype was analyzed by immunohistochemistry and ex vivo magnetic resonance imaging. F344tgHD rats displayed markedly reduced anxiety-like behavior in the social interaction test and elevated impulsivity traits already at 3 months of age. Neuropathologically, reduced striatal volume and pronounced aggregation of mutant huntingtin in several brain regions were detected at later disease stage. In conclusion, the congenic F344tgHD model reproduces key aspects of the human HD phenotype, substantiating its value for translational therapeutic approaches.
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Affiliation(s)
- Anne-Christine Plank
- Experimental Therapy, Preclinical Experimental Center, University Clinics Erlangen, Erlangen, Germany
| | - Fabio Canneva
- Experimental Therapy, Preclinical Experimental Center, University Clinics Erlangen, Erlangen, Germany
| | - Kerstin A Raber
- Experimental Therapy, Preclinical Experimental Center, University Clinics Erlangen, Erlangen, Germany
| | - Yvonne K Urbach
- Experimental Therapy, Preclinical Experimental Center, University Clinics Erlangen, Erlangen, Germany
| | - Julia Dobner
- Experimental Therapy, Preclinical Experimental Center, University Clinics Erlangen, Erlangen, Germany
| | - Maja Puchades
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Jan G Bjaalie
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Clarissa Gillmann
- Preclinical Imaging Platform Erlangen, Institute of Radiology, University Clinics Erlangen, Erlangen, Germany
| | - Tobias Bäuerle
- Preclinical Imaging Platform Erlangen, Institute of Radiology, University Clinics Erlangen, Erlangen, Germany
| | - Olaf Riess
- Institute of Medical Genetics and Applied Genomics, University Clinics Tuebingen, Tuebingen, Germany
| | - Hoa H P Nguyen
- Institute of Medical Genetics and Applied Genomics, University Clinics Tuebingen, Tuebingen, Germany
| | - Stephan von Hörsten
- Experimental Therapy, Preclinical Experimental Center, University Clinics Erlangen, Erlangen, Germany
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15
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De Mello WC, Gerena Y, Ayala-Peña S. Angiotensins and Huntington's Disease: A Study on Immortalized Progenitor Striatal Cell Lines. Front Endocrinol (Lausanne) 2017; 8:108. [PMID: 28596754 PMCID: PMC5442183 DOI: 10.3389/fendo.2017.00108] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 05/03/2017] [Indexed: 12/21/2022] Open
Abstract
Neurons from mouse models of Huntington's disease (HD) exhibit altered electrophysiological properties, potentially contributing to neuronal dysfunction and neurodegeneration. The renin-angiotensin system (RAS) is a potential contributor to the pathophysiology of neurodegenerative diseases. However, the role of angiotensin II (Ang II) and angiotensin (1-7) has not been characterized in HD. We investigated the influence of Ang II and angiotensin (1-7) on total potassium current using immortalized progenitor mutant huntingtin-expressing (Q111) and wild-type (Q7) cell lines. Measurements of potassium current were performed using the whole cell configuration of pCLAMP. The results showed that (1) the effect of Ang II administered to the bath caused a negligible effect on potassium current in mutant Q111 cells compared with wild-type Q7 cells and that intracellular administration of Ang II reduced the potassium current in wild type but not in mutant cells; (2) the small effect of Ang II was abolished by losartan; (3) intracellular administration of Ang II performed in mutant huntingtin-expressing Q111 cells revealed a negligible effect of the peptide on potassium current; (4) flow cytometer analysis indicated a low expression of Ang II AT1 receptors in mutant Q111 cells; (5) mutant huntingtin-expressing striatal cells are highly sensitive to Ang (1-7) and that the effect of Ang (1-7) is related to the activation of Mas receptors. In conclusion, mutant huntingtin-expressing cells showed a negligible effect of Ang II on potassium current, a result probably due to the reduced expression of AT1 receptors at the surface cell membrane. In contrast, administration of Ang (1-7) to the bath showed a significant decline of the potassium current in mutant cells, an effect dependent on the activation of Mas receptors. Ang II had an intracrine effect in wild-type cells and Ang (1-7) exerted a significant effect in mutant huntingtin-expressing striatal cells.
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Affiliation(s)
- Walmor C. De Mello
- Department of Pharmacology and Toxicology, School of Medicine, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, USA
| | - Yamil Gerena
- Department of Pharmacology and Toxicology, School of Medicine, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, USA
| | - Sylvette Ayala-Peña
- Department of Pharmacology and Toxicology, School of Medicine, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, USA
- *Correspondence: Sylvette Ayala-Peña,
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16
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Lokhande S, Patra BN, Ray A. A link between chromatin condensation mechanisms and Huntington's disease: connecting the dots. MOLECULAR BIOSYSTEMS 2016; 12:3515-3529. [PMID: 27714015 DOI: 10.1039/c6mb00598e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Huntington's disease is a rare neurodegenerative disorder whose complex pathophysiology exhibits system-wide changes in the body, with striking and debilitating clinical features targeting the central nervous system. Among the various molecular functions affected in this disease, mitochondrial dysfunction and transcriptional dysregulation are some of the most studied aspects of this disease. However, there is evidence of the involvement of a mutant Huntingtin protein in the processes of DNA damage, chromosome condensation and DNA repair. This review attempts to briefly recapitulate the clinical features, model systems used to study the disease, major molecular processes affected, and, more importantly, examines recent evidence for the involvement of the mutant Huntingtin protein in the processes regulating chromosome condensation, leading to DNA damage response and neuronal death.
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Affiliation(s)
- Sonali Lokhande
- Keck Graduate Institute of Applied Life Sciences, Claremont, CA 91711, USA.
| | - Biranchi N Patra
- Keck Graduate Institute of Applied Life Sciences, Claremont, CA 91711, USA.
| | - Animesh Ray
- Keck Graduate Institute of Applied Life Sciences, Claremont, CA 91711, USA.
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17
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Old Things New View: Ascorbic Acid Protects the Brain in Neurodegenerative Disorders. Int J Mol Sci 2015; 16:28194-217. [PMID: 26633354 PMCID: PMC4691042 DOI: 10.3390/ijms161226095] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/23/2015] [Accepted: 10/14/2015] [Indexed: 12/13/2022] Open
Abstract
Ascorbic acid is a key antioxidant of the Central Nervous System (CNS). Under brain activity, ascorbic acid is released from glial reservoirs to the synaptic cleft, where it is taken up by neurons. In neurons, ascorbic acid scavenges reactive oxygen species (ROS) generated during synaptic activity and neuronal metabolism where it is then oxidized to dehydroascorbic acid and released into the extracellular space, where it can be recycled by astrocytes. Other intrinsic properties of ascorbic acid, beyond acting as an antioxidant, are important in its role as a key molecule of the CNS. Ascorbic acid can switch neuronal metabolism from glucose consumption to uptake and use of lactate as a metabolic substrate to sustain synaptic activity. Multiple evidence links oxidative stress with neurodegeneration, positioning redox imbalance and ROS as a cause of neurodegeneration. In this review, we focus on ascorbic acid homeostasis, its functions, how it is used by neurons and recycled to ensure antioxidant supply during synaptic activity and how this antioxidant is dysregulated in neurodegenerative disorders.
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18
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Abstract
Mitochondria are highly specialized in function, but mitochondrial and, therefore, cellular integrity is maintained through their dynamic nature. Through the frequent processes of fusion and fission, mitochondria continuously change in shape and adjust function to meet cellular requirements. Abnormalities in fusion/fission dynamics generate cellular dysfunction that may lead to diseases. Mutations in the genes encoding mitochondrial fusion/fission proteins, such as MFN2 and OPA1, have been associated with an increasing number of genetic disorders, including Charcot-Marie-Tooth disease type 2A (CMT2A) and autosomal dominant optic atrophy. In this review, we address the mitochondrial dynamic changes in several important genetic diseases, which will bring the new insight of clinical relevance of mitochondrial genetics.
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Affiliation(s)
- Le Chen
- Molecular & Cellular Cardiology, University of California, Davis, One Shields Avenue Davis, CA, 95616, USA,
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19
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Duan W, Jiang M, Jin J. Metabolism in HD: still a relevant mechanism? Mov Disord 2014; 29:1366-74. [PMID: 25124273 DOI: 10.1002/mds.25992] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 07/22/2014] [Indexed: 12/14/2022] Open
Abstract
The polyglutamine expansion within huntingtin is the causative factor in the pathogenesis of Huntington's disease (HD). Although the underlying mechanisms by which mutant huntingtin causes neuronal dysfunction and degeneration have not been fully elucidated, compelling evidence suggests that mitochondrial dysfunction and compromised energy metabolism are key players in HD pathogenesis. Longitudinal studies of HD subjects have shown reductions in glucose utilization before the disease clinical onset. Preferential striatal neurodegeneration, a hallmark of HD pathogenesis, also has been associated with interrupted energy metabolism. Data from genetic HD models indicate that mutant huntingtin disrupts mitochondrial bioenergetics and prevents adenosine triphosphate (ATP) generation, implying altered energy metabolism as an important component of HD pathogenesis. Here we revisit the evidence of abnormal energy metabolism in the central nervous system of HD patients, review our current understanding of the molecular mechanisms underlying abnormal metabolism induced by mutant huntingtin, and discuss the promising therapeutic development by halting abnormal metabolism in HD.
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Affiliation(s)
- Wenzhen Duan
- Division of Neurobiology, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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20
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Eckmann J, Clemens LE, Eckert SH, Hagl S, Yu-Taeger L, Bordet T, Pruss RM, Muller WE, Leuner K, Nguyen HP, Eckert GP. Mitochondrial membrane fluidity is consistently increased in different models of Huntington disease: restorative effects of olesoxime. Mol Neurobiol 2014; 50:107-18. [PMID: 24633813 DOI: 10.1007/s12035-014-8663-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 02/18/2014] [Indexed: 12/12/2022]
Abstract
Huntington disease (HD) is a fatal neurodegenerative disorder caused by a CAG repeat expansion in exon 1 of the huntingtin gene (HTT). One prominent target of the mutant huntingtin protein (mhtt) is the mitochondrion, affecting its morphology, distribution, and function. Thus, mitochondria have been suggested as potential therapeutic targets for the treatment of HD. Olesoxime, a cholesterol-like compound, promotes motor neuron survival and neurite outgrowth in vitro, and its effects are presumed to occur via a direct interaction with mitochondrial membranes (MMs). We examined the properties of MMs isolated from cell and animal models of HD as well as the effects of olesoxime on MM fluidity and cholesterol levels. MMs isolated from brains of aged Hdh Q111/Q111 knock-in mice showed a significant decrease in 1,6-diphenyl-hexatriene (DPH) anisotropy, which is inversely correlated with membrane fluidity. Similar increases in MM fluidity were observed in striatal STHdh Q111/Q111 cells as well as in MMs isolated from brains of BACHD transgenic rats. Treatment of STHdh cells with olesoxime decreased the fluidity of isolated MMs. Decreased membrane fluidity was also measured in olesoxime-treated MMs isolated from brains of HD knock-in mice. In both models, treatment with olesoxime restored HD-specific changes in MMs. Accordingly, olesoxime significantly counteracted the mhtt-induced increase in MM fluidity of MMs isolated from brains of BACHD rats after 12 months of treatment in vivo, possibly by enhancing MM cholesterol levels. Thus, olesoxime may represent a novel pharmacological tool to treat mitochondrial dysfunction in HD.
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Affiliation(s)
- Janett Eckmann
- Department of Pharmacology, Biocenter, Goethe-University Campus Riedberg, Biocentre Geb. N260, R.1.09, Max-von-Laue Str. 9, 60438, Frankfurt, Germany
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21
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Chaturvedi RK, Flint Beal M. Mitochondrial diseases of the brain. Free Radic Biol Med 2013; 63:1-29. [PMID: 23567191 DOI: 10.1016/j.freeradbiomed.2013.03.018] [Citation(s) in RCA: 313] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 12/13/2022]
Abstract
Neurodegenerative disorders are debilitating diseases of the brain, characterized by behavioral, motor and cognitive impairments. Ample evidence underpins mitochondrial dysfunction as a central causal factor in the pathogenesis of neurodegenerative disorders including Parkinson's disease, Huntington's disease, Alzheimer's disease, Amyotrophic lateral sclerosis, Friedreich's ataxia and Charcot-Marie-Tooth disease. In this review, we discuss the role of mitochondrial dysfunction such as bioenergetics defects, mitochondrial DNA mutations, gene mutations, altered mitochondrial dynamics (mitochondrial fusion/fission, morphology, size, transport/trafficking, and movement), impaired transcription and the association of mutated proteins with mitochondria in these diseases. We highlight the therapeutic role of mitochondrial bioenergetic agents in toxin and in cellular and genetic animal models of neurodegenerative disorders. We also discuss clinical trials of bioenergetics agents in neurodegenerative disorders. Lastly, we shed light on PGC-1α, TORC-1, AMP kinase, Nrf2-ARE, and Sirtuins as novel therapeutic targets for neurodegenerative disorders.
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Affiliation(s)
- Rajnish K Chaturvedi
- CSIR-Indian Institute of Toxicology Research, 80 MG Marg, Lucknow 226001, India.
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22
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Faure A, Es-Seddiqi M, Brown BL, Nguyen HP, Riess O, von Hörsten S, Le Blanc P, Desvignes N, Bozon B, El Massioui N, Doyère V. Modified impact of emotion on temporal discrimination in a transgenic rat model of Huntington disease. Front Behav Neurosci 2013; 7:130. [PMID: 24133419 PMCID: PMC3783849 DOI: 10.3389/fnbeh.2013.00130] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 09/10/2013] [Indexed: 11/13/2022] Open
Abstract
Huntington's disease (HD) is characterized by triad of motor, cognitive, and emotional symptoms along with neuropathology in fronto-striatal circuit and limbic system including amygdala. Emotional alterations, which have a negative impact on patient well-being, represent some of the earliest symptoms of HD and might be related to the onset of the neurodegenerative process. In the transgenic rat model (tgHD rats), evidence suggest emotional alterations at the symptomatic stage along with neuropathology of the central nucleus of amygdala (CE). Studies in humans and animals demonstrate that emotion can modulate time perception. The impact of emotion on time perception has never been tested in HD, nor is it known if that impact could be part of the presymptomatic emotional phenotype of the pathology. The aim of this paper was to characterize the effect of emotion on temporal discrimination in presymptomatic tgHD animals. In the first experiment, we characterized the acute effect of an emotion (fear) conditioned stimulus on temporal discrimination using a bisection procedure, and tested its dependency upon an intact central amygdala. The second experiment was aimed at comparing presymptomatic homozygous transgenic animals at 7-months of age and their wild-type littermates (WT) in their performance on the modulation of temporal discrimination by emotion. Our principal findings show that (1) a fear cue produces a short-lived decrease of temporal precision after its termination, and (2) animals with medial CE lesion and presymptomatic tgHD animals demonstrate an alteration of this emotion-evoked temporal distortion. The results contribute to our knowledge about the presymptomatic phenotype of this HD rat model, showing susceptibility to emotion that may be related to dysfunction of the central nucleus of amygdala.
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Affiliation(s)
- Alexis Faure
- Centre de Neurosciences Paris-Sud, Université Paris-Sud, UMR 8195 Orsay, France ; Centre National de la Recherche Scientifique Orsay, France
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23
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Ayala-Peña S. Role of oxidative DNA damage in mitochondrial dysfunction and Huntington's disease pathogenesis. Free Radic Biol Med 2013; 62:102-110. [PMID: 23602907 PMCID: PMC3722255 DOI: 10.1016/j.freeradbiomed.2013.04.017] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 02/21/2013] [Accepted: 04/12/2013] [Indexed: 12/20/2022]
Abstract
Huntington's disease (HD) is a neurodegenerative disorder with an autosomal dominant expression pattern and typically a late-onset appearance. HD is a movement disorder with a heterogeneous phenotype characterized by involuntary dance-like gait, bioenergetic deficits, motor impairment, and cognitive and psychiatric deficits. Compelling evidence suggests that increased oxidative stress and mitochondrial dysfunction may underlie HD pathogenesis. However, the exact mechanisms underlying mutant huntingtin-induced neurological toxicity remain unclear. The objective of this paper is to review recent literature regarding the role of oxidative DNA damage in mitochondrial dysfunction and HD pathogenesis.
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Affiliation(s)
- Sylvette Ayala-Peña
- Department of Pharmacology and Toxicology, University of Puerto Rico Medical Sciences Campus, P.O. Box 365067, San Juan, Puerto Rico 00936-5067.
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24
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Ebel P, Vom Dorp K, Petrasch-Parwez E, Zlomuzica A, Kinugawa K, Mariani J, Minich D, Ginkel C, Welcker J, Degen J, Eckhardt M, Dere E, Dörmann P, Willecke K. Inactivation of ceramide synthase 6 in mice results in an altered sphingolipid metabolism and behavioral abnormalities. J Biol Chem 2013; 288:21433-21447. [PMID: 23760501 DOI: 10.1074/jbc.m113.479907] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The N-acyl chain length of ceramides is determined by the specificity of different ceramide synthases (CerS). The CerS family in mammals consists of six members with different substrate specificities and expression patterns. We have generated and characterized a mouse line harboring an enzymatically inactive ceramide synthase 6 (CerS6KO) gene and lacz reporter cDNA coding for β-galactosidase directed by the CerS6 promoter. These mice display a decrease in C16:0 containing sphingolipids. Relative to wild type tissues the amount of C16:0 containing sphingomyelin in kidney is ∼35%, whereas we find a reduction of C16:0 ceramide content in the small intestine to about 25%. The CerS6KO mice show behavioral abnormalities including a clasping abnormality of their hind limbs and a habituation deficit. LacZ reporter expression in the brain reveals CerS6 expression in hippocampus, cortex, and the Purkinje cell layer of the cerebellum. Using newly developed antibodies that specifically recognize the CerS6 protein we show that the endogenous CerS6 protein is N-glycosylated and expressed in several tissues of mice, mainly kidney, small and large intestine, and brain.
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Affiliation(s)
- Philipp Ebel
- From the Molecular Genetics, Life and Medical Sciences Institute (LIMES)
| | | | - Elisabeth Petrasch-Parwez
- the Department of Neuroanatomy and Molecular Brain Research, Ruhr-University of Bochum, 44801 Bochum, Germany
| | - Armin Zlomuzica
- the Mental Health Research and Treatment Center, Ruhr-University of Bochum, 44780 Bochum, Germany
| | - Kiyoka Kinugawa
- the Hôpital Charles Foix, Institut de la longévité, Paris 94205, France,; the Université Pierre et Marie Curie, Neurobiologie des Processus Adaptatifs, Paris 75005, France, and
| | - Jean Mariani
- the Hôpital Charles Foix, Institut de la longévité, Paris 94205, France,; the Université Pierre et Marie Curie, Neurobiologie des Processus Adaptatifs, Paris 75005, France, and
| | - David Minich
- From the Molecular Genetics, Life and Medical Sciences Institute (LIMES)
| | - Christina Ginkel
- From the Molecular Genetics, Life and Medical Sciences Institute (LIMES)
| | - Jochen Welcker
- the Department of Neuroscience, Max-Delbrueck-Centrum, Berlin, 13125 Berlin, Germany
| | - Joachim Degen
- From the Molecular Genetics, Life and Medical Sciences Institute (LIMES)
| | - Matthias Eckhardt
- the Institute of Biochemistry and Molecular Biology, University of Bonn, 53115 Bonn, Germany
| | - Ekrem Dere
- the Mental Health Research and Treatment Center, Ruhr-University of Bochum, 44780 Bochum, Germany,; the Hôpital Charles Foix, Institut de la longévité, Paris 94205, France,; the Université Pierre et Marie Curie, Neurobiologie des Processus Adaptatifs, Paris 75005, France, and
| | - Peter Dörmann
- Institute of Molecular Physiology and Biotechnology of Plants, and
| | - Klaus Willecke
- From the Molecular Genetics, Life and Medical Sciences Institute (LIMES),.
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25
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Kelp A, Koeppen AH, Petrasch-Parwez E, Calaminus C, Bauer C, Portal E, Yu-Taeger L, Pichler B, Bauer P, Riess O, Nguyen HP. A novel transgenic rat model for spinocerebellar ataxia type 17 recapitulates neuropathological changes and supplies in vivo imaging biomarkers. J Neurosci 2013; 33:9068-81. [PMID: 23699518 PMCID: PMC6705027 DOI: 10.1523/jneurosci.5622-12.2013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 03/18/2013] [Accepted: 04/09/2013] [Indexed: 02/05/2023] Open
Abstract
Spinocerebellar ataxia 17 (SCA17) is an autosomal-dominant, late-onset neurodegenerative disorder caused by an expanded polyglutamine (polyQ) repeat in the TATA-box-binding protein (TBP). To further investigate this devastating disease, we sought to create a first transgenic rat model for SCA17 that carries a full human cDNA fragment of the TBP gene with 64 CAA/CAG repeats (TBPQ64). In line with previous observations in mouse models for SCA17, TBPQ64 rats show a severe neurological phenotype including ataxia, impairment of postural reflexes, and hyperactivity in early stages followed by reduced activity, loss of body weight, and early death. Neuropathologically, the severe phenotype of SCA17 rats was associated with neuronal loss, particularly in the cerebellum. Degeneration of Purkinje, basket, and stellate cells, changes in the morphology of the dendrites, nuclear TBP-positive immunoreactivity, and axonal torpedos were readily found by light and electron microscopy. While some of these changes are well recapitulated in existing mouse models for SCA17, we provide evidence that some crucial characteristics of SCA17 are better mirrored in TBPQ64 rats. Thus, this SCA17 model represents a valuable tool to pursue experimentation and therapeutic approaches that may be difficult or impossible to perform with SCA17 transgenic mice. We show for the first time positron emission tomography (PET) and diffusion tensor imaging (DTI) data of a SCA animal model that replicate recent PET studies in human SCA17 patients. Our results also confirm that DTI are potentially useful correlates of neuropathological changes in TBPQ64 rats and raise hope that DTI imaging could provide a biomarker for SCA17 patients.
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Affiliation(s)
- Alexandra Kelp
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
| | - Arnulf H. Koeppen
- Department of Neuropathology and Neurology, Albany, New York 12208, and
| | - Elisabeth Petrasch-Parwez
- Department of Neuroanatomy and Molecular Brain Research, Ruhr-University Bochum, 44787 Bochum, Germany
| | - Carsten Calaminus
- Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation, and
| | - Claudia Bauer
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
| | - Esteban Portal
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
| | - Libo Yu-Taeger
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
| | - Bernd Pichler
- Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation, and
| | - Peter Bauer
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
| | - Olaf Riess
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
| | - Huu Phuc Nguyen
- Institute of Medical Genetics and Applied Genomics
- Centre for Rare Diseases Tübingen, University of Tübingen, 72076 Tübingen, Germany
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26
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A novel BACHD transgenic rat exhibits characteristic neuropathological features of Huntington disease. J Neurosci 2013; 32:15426-38. [PMID: 23115180 DOI: 10.1523/jneurosci.1148-12.2012] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Huntington disease (HD) is an inherited progressive neurodegenerative disorder, characterized by motor, cognitive, and psychiatric deficits as well as neurodegeneration and brain atrophy beginning in the striatum and the cortex and extending to other subcortical brain regions. The genetic cause is an expansion of the CAG repeat stretch in the HTT gene encoding huntingtin protein (htt). Here, we generated an HD transgenic rat model using a human bacterial artificial chromosome (BAC), which contains the full-length HTT genomic sequence with 97 CAG/CAA repeats and all regulatory elements. BACHD transgenic rats display a robust, early onset and progressive HD-like phenotype including motor deficits and anxiety-related symptoms. In contrast to BAC and yeast artificial chromosome HD mouse models that express full-length mutant huntingtin, BACHD rats do not exhibit an increased body weight. Neuropathologically, the distribution of neuropil aggregates and nuclear accumulation of N-terminal mutant huntingtin in BACHD rats is similar to the observations in human HD brains. Aggregates occur more frequently in the cortex than in the striatum and neuropil aggregates appear earlier than mutant htt accumulation in the nucleus. Furthermore, we found an imbalance in the striatal striosome and matrix compartments in early stages of the disease. In addition, reduced dopamine receptor binding was detectable by in vivo imaging. Our data demonstrate that this transgenic BACHD rat line may be a valuable model for further understanding the disease mechanisms and for preclinical pharmacological studies.
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27
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Chaturvedi RK, Beal MF. Mitochondria targeted therapeutic approaches in Parkinson's and Huntington's diseases. Mol Cell Neurosci 2012; 55:101-14. [PMID: 23220289 DOI: 10.1016/j.mcn.2012.11.011] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 11/20/2012] [Accepted: 11/27/2012] [Indexed: 12/18/2022] Open
Abstract
Substantial evidence from both genetic and toxin induced animal and cellular models and postmortem human brain tissue indicates that mitochondrial dysfunction plays a central role in pathophysiology of the neurodegenerative disorders including Parkinson's disease (PD), and Huntington's disease (HD). This review discusses the emerging understanding of the role of mitochondrial dysfunction including bioenergetics defects, mitochondrial DNA mutations, familial nuclear DNA mutations, altered mitochondrial fusion/fission and morphology, mitochondrial transport/trafficking, altered transcription and increased interaction of pathogenic proteins with mitochondria in the pathogenesis of PD and HD. This review recapitulates some of the key therapeutic strategies applied to surmount mitochondrial dysfunction in these debilitating disorders. We discuss the therapeutic role of mitochondrial bioenergetic agents such as creatine, Coenzyme-Q10, mitochondrial targeted antioxidants and peptides, the SIRT1 activator resveratrol, and the pan-PPAR agonist bezafibrate in toxin and genetic cellular and animal models of PD and HD. We also summarize the phase II-III clinical trials conducted using some of these agents. Lastly, we discuss PGC-1α, TORC and Sirtuins as potential therapeutic targets for mitochondrial dysfunction in neurodegenerative disorders. This article is part of a Special Issue entitled 'Mitochondrial function and dysfunction in neurodegeneration'.
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Affiliation(s)
- Rajnish K Chaturvedi
- Developmental Toxicology Division, Systems Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), 80 MG Marg, Lucknow 226001, India.
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Siddiqui A, Rivera-Sánchez S, del R. Castro M, Acevedo-Torres K, Rane A, Torres-Ramos CA, Nicholls DG, Andersen JK, Ayala-Torres S. Mitochondrial DNA damage is associated with reduced mitochondrial bioenergetics in Huntington's disease. Free Radic Biol Med 2012; 53:1478-88. [PMID: 22709585 PMCID: PMC3846402 DOI: 10.1016/j.freeradbiomed.2012.06.008] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 06/06/2012] [Accepted: 06/07/2012] [Indexed: 11/25/2022]
Abstract
Oxidative stress and mitochondrial dysfunction have been implicated in the pathology of HD; however, the precise mechanisms by which mutant huntingtin modulates levels of oxidative damage in turn resulting in mitochondrial dysfunction are not known. We hypothesize that mutant huntingtin increases oxidative mtDNA damage leading to mitochondrial dysfunction. We measured nuclear and mitochondrial DNA lesions and mitochondrial bioenergetics in the STHdhQ7 and STHdhQ111 in vitro striatal model of HD. Striatal cells expressing mutant huntingtin show higher basal levels of mitochondrial-generated ROS and mtDNA lesions and a lower spare respiratory capacity. Silencing of APE1, the major mammalian apurinic/apyrimidinic (AP) endonuclease that participates in the base excision repair (BER) pathway, caused further reductions of spare respiratory capacity in the mutant huntingtin-expressing cells. Localization experiments show that APE1 increases in the mitochondria of wild-type Q7 cells but not in the mutant huntingtin Q111 cells after treatment with hydrogen peroxide. Moreover, these results are recapitulated in human HD striata and HD skin fibroblasts that show significant mtDNA damage (increased lesion frequency and mtDNA depletion) and significant decreases in spare respiratory capacity, respectively. These data suggest that mtDNA is a major target of mutant huntingtin-associated oxidative stress and may contribute to subsequent mitochondrial dysfunction and that APE1 (and, by extension, BER) is an important target in the maintenance of mitochondrial function in HD.
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Affiliation(s)
| | - Sulay Rivera-Sánchez
- Department of Biochemistry, University of Puerto Rico Medical Sciences Campus, San Juan, PR
| | - María del R. Castro
- Department of Pharmacology and Toxicology, University of Puerto Rico Medical Sciences Campus, San Juan, PR
| | - Karina Acevedo-Torres
- Department of Physiology, University of Puerto Rico Medical Sciences Campus, San Juan, PR
| | - Anand Rane
- Buck Institute for Age Research, Novato, CA
| | - Carlos A. Torres-Ramos
- Department of Physiology, University of Puerto Rico Medical Sciences Campus, San Juan, PR
| | | | | | - Sylvette Ayala-Torres
- Department of Pharmacology and Toxicology, University of Puerto Rico Medical Sciences Campus, San Juan, PR
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Blockx I, Verhoye M, Van Audekerke J, Bergwerf I, Kane JX, Delgado Y Palacios R, Veraart J, Jeurissen B, Raber K, von Hörsten S, Ponsaerts P, Sijbers J, Leergaard TB, Van der Linden A. Identification and characterization of Huntington related pathology: an in vivo DKI imaging study. Neuroimage 2012; 63:653-62. [PMID: 22743196 DOI: 10.1016/j.neuroimage.2012.06.032] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 06/10/2012] [Accepted: 06/15/2012] [Indexed: 12/31/2022] Open
Abstract
An important focus of Huntington Disease (HD) research is the identification of symptom-independent biomarkers of HD neuropathology. There is an urgent need for reproducible, sensitive and specific outcome measures, which can be used to track disease onset as well as progression. Neuroimaging studies, in particular diffusion-based MRI methods, are powerful probes for characterizing the effects of disease and aging on tissue microstructure. We report novel diffusional kurtosis imaging (DKI) findings in aged transgenic HD rats. We demonstrate altered diffusion metrics in the (pre)frontal cerebral cortex, external capsule and striatum. Presence of increased diffusion complexity and restriction in the striatum is confirmed by an increased fiber dispersion in this region. Immunostaining of the same specimens reveals decreased number of microglia in the (pre)frontal cortex, and increased numbers of oligodendrocytes in the striatum. We conclude that DKI allows sensitive and specific characterization of altered tissue integrity in this HD rat model, indicating a promising potential for diagnostic imaging of gray and white matter pathology.
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Affiliation(s)
- Ines Blockx
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium.
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30
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Altered diffusion tensor imaging measurements in aged transgenic Huntington disease rats. Brain Struct Funct 2012; 218:767-78. [PMID: 22618438 PMCID: PMC3586769 DOI: 10.1007/s00429-012-0427-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Accepted: 04/30/2012] [Indexed: 11/12/2022]
Abstract
Rodent models of Huntington disease (HD) are valuable tools for investigating HD pathophysiology and evaluating new therapeutic approaches. Non-invasive characterization of HD-related phenotype changes is important for monitoring progression of pathological processes and possible effects of interventions. The first transgenic rat model for HD exhibits progressive late-onset affective, cognitive, and motor impairments, as well as neuropathological features reflecting observations from HD patients. In this report, we contribute to the anatomical phenotyping of this model by comparing high-resolution ex vivo DTI measurements obtained in aged transgenic HD rats and wild-type controls. By region of interest analysis supplemented by voxel-based statistics, we find little evidence of atrophy in basal ganglia regions, but demonstrate altered DTI measurements in the dorsal and ventral striatum, globus pallidus, entopeduncular nucleus, substantia nigra, and hippocampus. These changes are largely compatible with DTI findings in preclinical and clinical HD patients. We confirm earlier reports that HD rats express a moderate neuropathological phenotype, and provide evidence of altered DTI measures in specific HD-related brain regions, in the absence of pronounced morphometric changes.
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31
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Zeef DH, van Goethem NP, Vlamings R, Schaper F, Jahanshahi A, Hescham S, von Hörsten S, Prickaerts J, Temel Y. Memory deficits in the transgenic rat model of Huntington's disease. Behav Brain Res 2012; 227:194-8. [DOI: 10.1016/j.bbr.2011.11.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 11/04/2011] [Accepted: 11/06/2011] [Indexed: 11/26/2022]
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Olfactory neuron-specific expression of A30P alpha-synuclein exacerbates dopamine deficiency and hyperactivity in a novel conditional model of early Parkinson's disease stages. Neurobiol Dis 2011; 44:192-204. [DOI: 10.1016/j.nbd.2011.06.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 06/05/2011] [Accepted: 06/26/2011] [Indexed: 11/19/2022] Open
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33
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Alexandru A, Jagla W, Graubner S, Becker A, Bäuscher C, Kohlmann S, Sedlmeier R, Raber KA, Cynis H, Rönicke R, Reymann KG, Petrasch-Parwez E, Hartlage-Rübsamen M, Waniek A, Rossner S, Schilling S, Osmand AP, Demuth HU, von Hörsten S. Selective hippocampal neurodegeneration in transgenic mice expressing small amounts of truncated Aβ is induced by pyroglutamate-Aβ formation. J Neurosci 2011; 31:12790-801. [PMID: 21900558 PMCID: PMC6623394 DOI: 10.1523/jneurosci.1794-11.2011] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 07/09/2011] [Accepted: 07/12/2011] [Indexed: 12/24/2022] Open
Abstract
Posttranslational amyloid-β (Aβ) modification is considered to play an important role in Alzheimer's disease (AD) etiology. An N-terminally modified Aβ species, pyroglutamate-amyloid-β (pE3-Aβ), has been described as a major constituent of Aβ deposits specific to human AD but absent in normal aging. Formed via cyclization of truncated Aβ species by glutaminyl cyclase (QC; QPCT) and/or its isoenzyme (isoQC; QPCTL), pE3-Aβ aggregates rapidly and is known to seed additional Aβ aggregation. To directly investigate pE3-Aβ toxicity in vivo, we generated and characterized transgenic TBA2.1 and TBA2.2 mice, which express truncated mutant human Aβ. Along with a rapidly developing behavioral phenotype, these mice showed progressively accumulating Aβ and pE3-Aβ deposits in brain regions of neuronal loss, impaired long-term potentiation, microglial activation, and astrocytosis. Illustrating a threshold for pE3-Aβ neurotoxicity, this phenotype was not found in heterozygous animals but in homozygous TBA2.1 or double-heterozygous TBA2.1/2.2 animals only. A significant amount of pE3-Aβ formation was shown to be QC-dependent, because crossbreeding of TBA2.1 with QC knock-out, but not isoQC knock-out, mice significantly reduced pE3-Aβ levels. Hence, lowering the rate of QC-dependent posttranslational pE3-Aβ formation can, in turn, lower the amount of neurotoxic Aβ species in AD.
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MESH Headings
- Aging/pathology
- Aging/psychology
- Alzheimer Disease/pathology
- Amyloid beta-Protein Precursor/biosynthesis
- Animals
- Behavior, Animal
- Brain/pathology
- Enzyme-Linked Immunosorbent Assay
- Gliosis/pathology
- Heredodegenerative Disorders, Nervous System/genetics
- Heredodegenerative Disorders, Nervous System/pathology
- Heredodegenerative Disorders, Nervous System/psychology
- Hippocampus/pathology
- Humans
- Immunohistochemistry
- Kinetics
- Long-Term Potentiation/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Mice, Transgenic
- Microscopy, Electron
- Neuronal Plasticity/genetics
- Neuronal Plasticity/physiology
- Phenotype
- Postural Balance/physiology
- Protein Processing, Post-Translational
- Pyrrolidonecarboxylic Acid/metabolism
- Reflex, Startle/physiology
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
| | | | | | | | | | | | | | - Kerstin A. Raber
- Experimental Therapy, Friedrich Alexander University Erlangen Nürnberg, 91054 Erlangen, Germany
| | | | - Raik Rönicke
- German Center of Neurodegenerative Diseases, 39120 Magdeburg, Germany
| | - Klaus G. Reymann
- German Center of Neurodegenerative Diseases, 39120 Magdeburg, Germany
- Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany
| | | | - Maike Hartlage-Rübsamen
- Paul Flechsig Institute for Brain Research, University of Leipzig, 04109 Leipzig, Germany, and
| | - Alexander Waniek
- Paul Flechsig Institute for Brain Research, University of Leipzig, 04109 Leipzig, Germany, and
| | - Steffen Rossner
- Paul Flechsig Institute for Brain Research, University of Leipzig, 04109 Leipzig, Germany, and
| | | | - Alexander P. Osmand
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee 37920
| | - Hans-Ulrich Demuth
- Ingenium Pharmaceuticals, 82152 Martinsried, Germany
- Probiodrug, 06120 Halle/Saale, Germany
| | - Stephan von Hörsten
- Experimental Therapy, Friedrich Alexander University Erlangen Nürnberg, 91054 Erlangen, Germany
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34
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Blockx I, Van Camp N, Verhoye M, Boisgard R, Dubois A, Jego B, Jonckers E, Raber K, Siquier K, Kuhnast B, Dollé F, Nguyen HP, Von Hörsten S, Tavitian B, Van der Linden A. Genotype specific age related changes in a transgenic rat model of Huntington's disease. Neuroimage 2011; 58:1006-16. [PMID: 21767653 DOI: 10.1016/j.neuroimage.2011.07.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 06/29/2011] [Accepted: 07/04/2011] [Indexed: 12/15/2022] Open
Abstract
We aimed to characterize the transgenic Huntington rat model with in vivo imaging and identify sensitive and reliable biomarkers associated with early and progressive disease status. In order to do so, we performed a multimodality (DTI and PET) longitudinal imaging study, during which the same TgHD and wildtype (Wt) rats were repetitively scanned. Surprisingly, the relative ventricle volume was smaller but increased faster in TgHD compared to Wt animals. DTI (mean, axial, radial diffusivity) revealed subtle genotype-specific aging effects in the striatum and its surrounding white matter, already in the presymptomatic stage. Using ¹⁸F-FDG and ¹⁸F-Fallypride PET imaging, we were not able to demonstrate genotype-specific aging effects within the striatum. The outcome of this longitudinal study was somewhat surprising as it demonstrated a significant differential aging pattern in TgHD versus Wt animals. Although it seems that the TgHD rat model does not have a sufficient expression of disease yet at the age of 12 months, further validation of this model is highly beneficial since there is still an incomplete understanding of the early disease mechanisms of Huntington's disease.
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Affiliation(s)
- Ines Blockx
- Bio-Imaging Lab, University of Antwerp, Belgium
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35
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Gerding WM, Schreiber S, Schulte-Middelmann T, de Castro Marques A, Atorf J, Akkad DA, Dekomien G, Kremers J, Dermietzel R, Gal A, Rülicke T, Ibrahim S, Epplen JT, Petrasch-Parwez E. Ccdc66 null mutation causes retinal degeneration and dysfunction. Hum Mol Genet 2011; 20:3620-31. [PMID: 21680557 DOI: 10.1093/hmg/ddr282] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Retinitis pigmentosa (RP) is a group of human retinal disorders, with more than 100 genes involved in retinal degeneration. Canine and murine models are useful for investigating human RP based on known, naturally occurring mutations. In Schapendoes dogs, for example, a mutation in the CCDC66 gene has been shown to cause autosomal recessively inherited, generalized progressive retinal atrophy (gPRA), the canine counterpart to RP. Here, a novel mouse model with a disrupted Ccdc66 gene was investigated to reveal the function of protein CCDC66 and the pathogenesis of this form of gPRA. Homozygous Ccdc66 mutant mice lack retinal Ccdc66 RNA and protein expression. Light and electron microscopy reveal an initial degeneration of photoreceptors already at 13 days of age, followed by a slow, progressive retinal degeneration over months. Retinal dysfunction causes reduced scotopic a-wave amplitudes, declining from 1 to 7 months of age as well as an early reduction of the photopic b-wave at 1 month, improving slightly at 7 months, as evidenced by electroretinography. In the retina of the wild-type (WT) mouse, protein CCDC66 is present at highest levels after birth, followed by a decline until adulthood, suggesting a crucial role in early development. Protein CCDC66 is expressed predominantly in the developing rod outer segments as confirmed by subcellular analyses. These findings illustrate that the lack of protein CCDC66 causes early, slow progressive rod-cone dysplasia in the novel Ccdc66 mutant mouse model, thus providing a sound foundation for the development of therapeutic strategies.
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Affiliation(s)
- Wanda M Gerding
- Department of Human Genetics, Ruhr-University,44780 Bochum, Germany
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36
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Transforming Growth Factor-Beta Signaling in the Neural Stem Cell Niche: A Therapeutic Target for Huntington's Disease. Neurol Res Int 2011; 2011:124256. [PMID: 21766020 PMCID: PMC3134994 DOI: 10.1155/2011/124256] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 02/19/2011] [Indexed: 12/31/2022] Open
Abstract
The neural stem cell niches possess the regenerative capacity to generate new functional neurons in the adult brain, suggesting the possibility of endogenous neuronal replacement after injury or disease. Huntington disease (HD) is a neurodegenerative disease and characterized by neuronal loss in the basal ganglia, leading to motor, cognitive, and psychological disabilities. Apparently, in order to make use of the neural stem cell niche as a therapeutic concept for repair strategies in HD, it is important to understand the cellular and molecular composition of the neural stem cell niche under such neurodegenerative conditions. This paper mainly discusses the current knowledge on the regulation of the hippocampal neural stem cell niche in the adult brain and by which mechanism it might be compromised in the case of HD.
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37
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Abstract
Human cortical excitability can be modified by repetitive transcranial magnetic stimulation (rTMS), but the cellular mechanisms are largely unknown. Here, we show that the pattern of delivery of theta-burst stimulation (TBS) (continuous versus intermittent) differently modifies electric activity and protein expression in the rat neocortex. Intermittent TBS (iTBS), but not continuous TBS (cTBS), enhanced spontaneous neuronal firing and EEG gamma band power. Sensory evoked cortical inhibition increased only after iTBS, although both TBS protocols increased the first sensory response arising from the resting cortical state. Changes in the cortical expression of the calcium-binding proteins parvalbumin (PV) and calbindin D-28k (CB) indicate that changes in spontaneous and evoked cortical activity following rTMS are in part related to altered activity of inhibitory systems. By reducing PV expression in the fast-spiking interneurons, iTBS primarily affected the inhibitory control of pyramidal cell output activity, while cTBS, by reducing CB expression, more likely affected the dendritic integration of synaptic inputs controlled by other classes of inhibitory interneurons. Calretinin, the third major calcium-binding protein expressed by another class of interneurons was not affected at all. We conclude that different patterns of TBS modulate the activity of inhibitory cell classes differently, probably depending on the synaptic connectivity and the preferred discharge pattern of these inhibitory neurons.
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Ellrichmann G, Petrasch-Parwez E, Lee DH, Reick C, Arning L, Saft C, Gold R, Linker RA. Efficacy of fumaric acid esters in the R6/2 and YAC128 models of Huntington's disease. PLoS One 2011; 6:e16172. [PMID: 21297955 PMCID: PMC3031519 DOI: 10.1371/journal.pone.0016172] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Accepted: 12/09/2010] [Indexed: 01/29/2023] Open
Abstract
Huntington's disease (HD) is an autosomal dominantly inherited progressive neurodegenerative disease. The exact sequel of events finally resulting in neurodegeneration is only partially understood and there is no established protective treatment so far. Some lines of evidence speak for the contribution of oxidative stress to neuronal tissue damage. The fumaric acid ester dimethylfumarate (DMF) is a new disease modifying therapy currently in phase III studies for relapsing-remitting multiple sclerosis. DMF potentially exerts neuroprotective effects via induction of the transcription factor “nuclear factor E2-related factor 2” (Nrf2) and detoxification pathways. Thus, we investigated here the therapeutic efficacy of DMF in R6/2 and YAC128 HD transgenic mice which mimic many aspects of HD and are characterized by an enhanced generation of free radicals in neurons. Treatment with DMF significantly prevented weight loss in R6/2 mice between postnatal days 80–90. At the same time, DMF treatment led to an attenuated motor impairment as measured by the clasping score. Average survival in the DMF group was 100.5 days vs. 94.0 days in the placebo group. In the histological analysis on day 80, DMF treatment resulted in a significant preservation of morphologically intact neurons in the striatum as well as in the motor cortex. DMF treatment resulted in an increased Nrf2 immunoreactivity in neuronal subpopulations, but not in astrocytes. These beneficial effects were corroborated in YAC128 mice which, after one year of DMF treatment, also displayed reduced dyskinesia as well as a preservation of neurons. In conclusion, DMF may exert beneficial effects in mouse models of HD. Given its excellent side effect profile, further studies with DMF as new therapeutic approach in HD and other neurodegenerative diseases are warranted.
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Affiliation(s)
- Gisa Ellrichmann
- Department of Neurology, St. Josef-Hospital, Ruhr-University Bochum, Bochum, Germany
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39
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Abstract
It has been more than 17 years since the causative mutation for Huntington's disease was discovered as the expansion of the triplet repeat in the N-terminal portion of the Huntingtin (HTT) gene. In the intervening time, researchers have discovered a great deal about Huntingtin's involvement in a number of cellular processes. However, the role of Huntingtin in the key pathogenic mechanism leading to neurodegeneration in the disease process has yet to be discovered. Here, we review the body of knowledge that has been uncovered since gene discovery and include discussions of the HTT gene, CAG triplet repeat expansion, HTT expression, protein features, posttranslational modifications, and many of its known protein functions and interactions. We also highlight potential pathogenic mechanisms that have come to light in recent years.
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Affiliation(s)
- Karen N McFarland
- Department of Neurology, University of Florida, Gainesville, FL 32610-0236, USA.
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40
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Stem cell quiescence in the hippocampal neurogenic niche is associated with elevated transforming growth factor-beta signaling in an animal model of Huntington disease. J Neuropathol Exp Neurol 2010; 69:717-28. [PMID: 20535034 DOI: 10.1097/nen.0b013e3181e4f733] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Cellular proliferation, differentiation, integration, and survival within the adult neural stem cell niche are altered under pathological conditions, but the molecular cues regulating the biology of this niche are mostly unknown. We examined the hippocampal neural stem cell niche in a transgenic rat model of Huntington disease. In this model, progressive cognitive deficits develop at the age of 9 months, suggesting possible hippocampal dysfunction. We found a disease-associated progressive decline in hippocampal progenitor cell proliferation accompanied by an expansion of the pool of 5-bromo-2-deoxyuridine label-retaining Sox-2-positive quiescent stem cells in the transgenic animals. Increments in quiescent stem cells occurred at the expense of cAMP-responsive element-binding protein-mediated neuronal differentiation and survival. Because elevated levels of transforming growth factor-beta1 (TGF-beta1) impair neural progenitor proliferation, we investigated hippocampal TGF-beta signaling and determined that TGF-beta1 induces the neural progenitors to exit the cell cycle. Although phospho-Smad2, an effector of TGF-beta signaling, is normally absent in subgranular stem cells, it accumulated progressively in Sox2/glial fibrillary acidic protein-expressing cells of the subgranular zone in the transgenic rats. These results indicate that alterations in neurogenesis in transgenic Huntington disease rats occur in successive phases that are associated with increasing TGF-beta signaling. Thus, TGF-beta1 signaling seems to be a crucial modulator of neurogenesis in Huntington disease and may represent a target for future therapy.
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41
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Byvaltsev V, Sudakov N, Nikiforov S, Konstantinov Y. Mitochondrial Dysfunction and Neurodegenerative Diseases. World Neurosurg 2010; 74:10-2. [DOI: 10.1016/j.wneu.2010.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Indexed: 11/24/2022]
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42
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Huntington’s disease and mitochondrial alterations: emphasis on experimental models. J Bioenerg Biomembr 2010; 42:207-15. [DOI: 10.1007/s10863-010-9289-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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43
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44
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Jafarian M, Rahimi S, Behnam F, Hosseini M, Haghir H, Sadeghzadeh B, Gorji A. The effect of repetitive spreading depression on neuronal damage in juvenile rat brain. Neuroscience 2010; 169:388-94. [PMID: 20438812 DOI: 10.1016/j.neuroscience.2010.04.062] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Revised: 04/20/2010] [Accepted: 04/25/2010] [Indexed: 10/19/2022]
Abstract
Spreading depression (SD) is pronounced depolarization of neurons and glia that travels slowly across brain tissue followed by massive redistribution of ions between intra- and extracellular compartments. There is a relationship between SD and some neurological disorders. In the present study the effects of repetitive SD on neuronal damage in cortical and subcortical regions of juvenile rat brain were investigated. The animals were anesthetized and the electrodes as well as cannula were implanted over the brain. SD-like event was induced by KCl injection. The brains were removed after 2 or 4 weeks after induction of 2 or 4 SD-like waves (with interval of 1 week), respectively. Normal saline was injected instead of KCl in sham group. For stereological study, paraffin-embedded brains were cut in 5 microm sections. The sections were stained with Toluidine Blue to measure the volume-weighted mean volume of normal neurons and the numerical density of dark neurons. The volume-weighted mean volume of normal neurons in the granular layer of the dentate gyrus and layer V of the temporal cortex in SD group were significantly decreased after four repetitive SD. Furthermore, densities of dark neurons in the granular layer of the dentate gyrus (after 2 weeks), the caudate-putamen, and layer V of the temporal cortex (after 4 weeks) were significantly increased in SD group. Repetitive cortical SD in juvenile rats may cause neuronal damage in cortical and subcortical areas of the brain. This may important in pathophysiology of SD-related neurological disorders.
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Affiliation(s)
- M Jafarian
- Department of Anatomy, Mashhad University of Medical Sciences, Mashhad, Iran; Shefa Neuroscience Center, Tehran, Iran
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45
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Squitieri F, Ciarmiello A. Key role of nuclear medicine in seeking biomarkers of Huntington’s disease. Eur J Nucl Med Mol Imaging 2010; 37:1124-7. [DOI: 10.1007/s00259-010-1439-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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46
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Transgenic overexpression of the alpha-synuclein interacting protein synphilin-1 leads to behavioral and neuropathological alterations in mice. Neurogenetics 2010; 11:107-20. [PMID: 19760259 DOI: 10.1007/s10048-009-0212-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 08/03/2009] [Indexed: 12/11/2022]
Abstract
Synphilin-1 has been identified as an interacting protein of alpha-synuclein, Parkin, and LRRK2, proteins which are mutated in familial forms of Parkinson disease (PD). Subsequently, synphilin-1 has also been shown to be an intrinsic component of Lewy bodies in sporadic PD. In order to elucidate the role of synphilin-1 in the pathogenesis of PD, we generated transgenic mice overexpressing wild-type and mutant (R621C) synphilin-1 driven by a mouse prion protein promoter. Transgenic expression of both wild-type and the R621C variant synphilin-1 resulted in increased dopamine levels of the nigrostriatal system in 3-month-old mice. Furthermore, we found pathological ubiquitin-positive inclusions in cerebellar sections and dark-cell degeneration of Purkinje cells. Both transgenic mouse lines showed significant reduction of motor skill learning and motor performance. These findings suggest a pathological role of overexpressed synphilin-1 in vivo and will help to further elucidate the mechanisms of protein aggregation and neuronal cell death.
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Duran R, Barrero FJ, Morales B, Luna JD, Ramirez M, Vives F. Oxidative stress and plasma aminopeptidase activity in Huntington’s disease. J Neural Transm (Vienna) 2010; 117:325-32. [DOI: 10.1007/s00702-009-0364-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Accepted: 12/23/2009] [Indexed: 11/30/2022]
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Miller BR, Walker AG, Fowler SC, von Hörsten S, Riess O, Johnson MA, Rebec GV. Dysregulation of coordinated neuronal firing patterns in striatum of freely behaving transgenic rats that model Huntington's disease. Neurobiol Dis 2010; 37:106-13. [PMID: 19818852 PMCID: PMC2787873 DOI: 10.1016/j.nbd.2009.09.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Revised: 09/04/2009] [Accepted: 09/27/2009] [Indexed: 10/20/2022] Open
Abstract
Altered neuronal activity in the striatum appears to be a key component of Huntington's disease (HD), a fatal, neurodegenerative condition. To assess this hypothesis in freely behaving transgenic rats that model HD (tgHDs), we used chronically implanted micro-wires to record the spontaneous activity of striatal neurons. We found that relative to wild-type controls, HD rats suffer from population-level deficits in striatal activity characterized by a loss of correlated firing and fewer episodes of coincident spike bursting between simultaneously recorded neuronal pairs. These results are in line with our previous report of marked alterations in the pattern of striatal firing in mouse models of HD that vary in background strain, genetic construct, and symptom severity. Thus, loss of coordinated spike activity in striatum appears to be a common feature of HD pathophysiology, regardless of HD model variability.
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Affiliation(s)
- Benjamin R Miller
- Program in Neuroscience and Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405, USA
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Su B, Wang X, Zheng L, Perry G, Smith MA, Zhu X. Abnormal mitochondrial dynamics and neurodegenerative diseases. Biochim Biophys Acta Mol Basis Dis 2009; 1802:135-42. [PMID: 19799998 DOI: 10.1016/j.bbadis.2009.09.013] [Citation(s) in RCA: 202] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 09/10/2009] [Accepted: 09/22/2009] [Indexed: 12/23/2022]
Abstract
Mitochondrial dysfunction is a prominent feature of various neurodegenerative diseases. A deeper understanding of the remarkably dynamic nature of mitochondria, characterized by a delicate balance of fission and fusion, has helped to fertilize a recent wave of new studies demonstrating abnormal mitochondrial dynamics in neurodegenerative diseases. This review highlights mitochondrial dysfunction and abnormal mitochondrial dynamics in Alzheimer disease, Parkinson disease, amyotrophic lateral sclerosis, and Huntington disease and discusses how these abnormal mitochondrial dynamics may contribute to mitochondrial and neuronal dysfunction. We propose that abnormal mitochondrial dynamics represents a key common pathway that mediates or amplifies mitochondrial dysfunction and neuronal dysfunction during the course of neurodegeneration.
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Affiliation(s)
- Bo Su
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
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Bunse S, Locovei S, Schmidt M, Qiu F, Zoidl G, Dahl G, Dermietzel R. The potassium channel subunit Kvbeta3 interacts with pannexin 1 and attenuates its sensitivity to changes in redox potentials. FEBS J 2009; 276:6258-70. [PMID: 19780818 DOI: 10.1111/j.1742-4658.2009.07334.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pannexin 1 (Panx1), a member of the second gap junction protein family identified in vertebrates, appears to preferentially form non-junctional membrane channels. A candidate regulatory protein of Panx1 is the potassium channel subunit Kvbeta3, previously identified by bacterial two-hybrid strategies. Here, we report on the physical association of Panx1 with Kvbeta3 by immunoprecipitation when co-expressed in a neuroblastoma cell line (Neuro2A). Furthermore, in vivo co-expression of Panx1 and Kvbeta3 was shown to occur in murine hippocampus and cerebellum. Kvbeta3 is known to accelerate inactivation of otherwise slowly inactivating potassium channels under reducing conditions. We subsequently found that Panx1 channel currents exhibit a significant reduction when exposed to reducing agents, and that this effect is attenuated in the presence of Kvbeta3. Apparently, Kvbeta3 is involved in regulating the susceptibility of Panx1 channels to redox potential. Furthermore, the Panx1 channel blockers carbenoxolone and Probenecid were less effective in inhibiting Panx1 currents when Kvbeta3 was co-expressed. The influence of Kvbeta3 on Panx1 is the first example of modulation of Panx1 channel function(s) by interacting proteins, and suggests the physiological importance of sensing changes in redox potentials.
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Affiliation(s)
- Stefanie Bunse
- Department of Neuroanatomy & Molecular Brain Research, Ruhr University, Bochum, Germany
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