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Tsekrekou M, Giannakou M, Papanikolopoulou K, Skretas G. Protein aggregation and therapeutic strategies in SOD1- and TDP-43- linked ALS. Front Mol Biosci 2024; 11:1383453. [PMID: 38855322 PMCID: PMC11157337 DOI: 10.3389/fmolb.2024.1383453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 05/02/2024] [Indexed: 06/11/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with severe socio-economic impact. A hallmark of ALS pathology is the presence of aberrant cytoplasmic inclusions composed of misfolded and aggregated proteins, including both wild-type and mutant forms. This review highlights the critical role of misfolded protein species in ALS pathogenesis, particularly focusing on Cu/Zn superoxide dismutase (SOD1) and TAR DNA-binding protein 43 (TDP-43), and emphasizes the urgent need for innovative therapeutic strategies targeting these misfolded proteins directly. Despite significant advancements in understanding ALS mechanisms, the disease remains incurable, with current treatments offering limited clinical benefits. Through a comprehensive analysis, the review focuses on the direct modulation of the misfolded proteins and presents recent discoveries in small molecules and peptides that inhibit SOD1 and TDP-43 aggregation, underscoring their potential as effective treatments to modify disease progression and improve clinical outcomes.
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Affiliation(s)
- Maria Tsekrekou
- Institute of Chemical Biology, National Hellenic Research Foundation, Athens, Greece
| | - Maria Giannakou
- Institute of Chemical Biology, National Hellenic Research Foundation, Athens, Greece
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Katerina Papanikolopoulou
- Institute for Fundamental Biomedical Research, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
- ResQ Biotech, Patras Science Park, Rio, Greece
| | - Georgios Skretas
- Institute of Chemical Biology, National Hellenic Research Foundation, Athens, Greece
- ResQ Biotech, Patras Science Park, Rio, Greece
- Institute for Bio-innovation, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
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2
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Pampalakis G, Angelis G, Zingkou E, Vekrellis K, Sotiropoulou G. A chemogenomic approach is required for effective treatment of amyotrophic lateral sclerosis. Clin Transl Med 2022; 12:e657. [PMID: 35064780 PMCID: PMC8783349 DOI: 10.1002/ctm2.657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 11/04/2021] [Accepted: 11/11/2021] [Indexed: 11/10/2022] Open
Abstract
ALS is a fatal untreatable disease involving degeneration of motor neurons. Μultiple causative genes encoding proteins with versatile functions have been identified indicating that diverse biological pathways lead to ALS. Chemical entities still represent a promising choice to delay ALS progression, attenuate symptoms and/or increase life expectancy, but also gene-based and stem cell-based therapies are in the process of development, and some are tested in clinical trials. Various compounds proved effective in transgenic models overexpressing distinct ALS causative genes unfortunately though, they showed no efficacy in clinical trials. Notably, while animal models provide a uniform genetic background for preclinical testing, ALS patients are not stratified, and the distinct genetic forms of ALS are treated as one group, which could explain the observed discrepancies between treating genetically homogeneous mice and quite heterogeneous patient cohorts. We suggest that chemical entity-genotype correlation should be exploited to guide patient stratification for pharmacotherapy, that is administered drugs should be selected based on the ALS genetic background.
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Affiliation(s)
- Georgios Pampalakis
- Department of Pharmacology - Pharmacognosy, School of Pharmacy, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Georgios Angelis
- Department of Pharmacology - Pharmacognosy, School of Pharmacy, Aristotle University of Thessaloniki, Thessaloniki, Greece
- Department of Pharmacy, School of Health Sciences, University of Patras, Rion-Patras, Greece
| | - Eleni Zingkou
- Department of Pharmacy, School of Health Sciences, University of Patras, Rion-Patras, Greece
| | - Kostas Vekrellis
- Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Georgia Sotiropoulou
- Department of Pharmacy, School of Health Sciences, University of Patras, Rion-Patras, Greece
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3
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Shiells H, Schelter BO, Bentham P, Baddeley TC, Rubino CM, Ganesan H, Hammel J, Vuksanovic V, Staff RT, Murray AD, Bracoud L, Wischik DJ, Riedel G, Gauthier S, Jia J, Moebius HJ, Hardlund J, Kipps CM, Kook K, Storey JMD, Harrington CR, Wischik CM. Concentration-Dependent Activity of Hydromethylthionine on Clinical Decline and Brain Atrophy in a Randomized Controlled Trial in Behavioral Variant Frontotemporal Dementia. J Alzheimers Dis 2021; 75:501-519. [PMID: 32280089 PMCID: PMC7306898 DOI: 10.3233/jad-191173] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Hydromethylthionine is a potent inhibitor of pathological aggregation of tau and TDP-43 proteins. OBJECTIVE To compare hydromethylthionine treatment effects at two doses and to determine how drug exposure is related to treatment response in bvFTD. METHODS We undertook a 52-week Phase III study in 220 bvFTD patients randomized to compare hydromethylthionine at 200 mg/day and 8 mg/day (intended as a control). The principal outcomes were change on the Addenbrookes Cognitive Examination - Revised (ACE-R), the Functional Activities Questionnaire (FAQ), and whole brain volume. Secondary outcomes included Modified Clinical Global Impression of Change (Modified-CGIC). A population pharmacokinetic exposure-response analysis was undertaken in 175 of the patients with available blood samples and outcome data using a discriminatory plasma assay for the parent drug. RESULTS There were no significant differences between the two doses as randomized. There were steep concentration-response relationships for plasma levels in the range 0.3-0.6 ng/ml at the 8 mg/day dose on clinical and MRI outcomes. There were significant exposure-dependent differences at 8 mg/day for FAQ, Modified-CGIC, and whole brain atrophy comparing patients with plasma levels greater than 0.346 ng/ml with having minimal drug exposure. The exposure-response is biphasic with worse outcomes at the high concentrations produced by 200 mg/day. CONCLUSIONS Hydromethylthionine has a similar concentration-response profile for effects on clinical decline and brain atrophy at the 8 mg/day dose in bvFTD as recently reported in AD. Treatment responses in bvFTD are predicted to be maximal at doses in the range 20-60 mg/day. A confirmatory placebo-controlled trial is now planned.
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Affiliation(s)
| | - Bjoern O Schelter
- TauRx Therapeutics Ltd., Aberdeen, UK.,Institute for Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, UK
| | | | - Thomas C Baddeley
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | | | - Harish Ganesan
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Jeffrey Hammel
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Vesna Vuksanovic
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Roger T Staff
- Aberdeen Royal Infirmary, NHS Grampian, Aberdeen, UK
| | - Alison D Murray
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | | | - Damon J Wischik
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Computer Science and Technology, University of Cambridge, Cambridge, UK
| | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Serge Gauthier
- McGill Centre for Studies in Aging, Alzheimer's Disease Research Unit, and Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Jianping Jia
- Beijing Institute for Brain Disorders Alzheimer's Disease Centre, Beijing, China
| | | | | | | | | | - John M D Storey
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | - Charles R Harrington
- TauRx Therapeutics Ltd., Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Claude M Wischik
- TauRx Therapeutics Ltd., Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
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Gumeni S, Vantaggiato C, Montopoli M, Orso G. Hereditary Spastic Paraplegia and Future Therapeutic Directions: Beneficial Effects of Small Compounds Acting on Cellular Stress. Front Neurosci 2021; 15:660714. [PMID: 34025345 PMCID: PMC8134669 DOI: 10.3389/fnins.2021.660714] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/29/2021] [Indexed: 12/29/2022] Open
Abstract
Hereditary spastic paraplegia (HSP) is a group of inherited neurodegenerative conditions that share a characteristic feature of degeneration of the longest axons within the corticospinal tract, which leads to progressive spasticity and weakness of the lower limbs. Mutations of over 70 genes produce defects in various biological pathways: axonal transport, lipid metabolism, endoplasmic reticulum (ER) shaping, mitochondrial function, and endosomal trafficking. HSPs suffer from an adequate therapeutic plan. Currently the treatments foreseen for patients affected by this pathology are physiotherapy, to maintain the outgoing tone, and muscle relaxant therapies for spasticity. Very few clinical studies have been conducted, and it's urgent to implement preclinical animal studies devoted to pharmacological test and screening, to expand the rose of compounds potentially attractive for clinical trials. Small animal models, such as Drosophila melanogaster and zebrafish, have been generated, analyzed, and used as preclinical model for screening of compounds and their effects. In this work, we briefly described the role of HSP-linked proteins in the organization of ER endomembrane system and in the regulation of ER homeostasis and stress as a common pathological mechanism for these HSP forms. We then focused our attention on the pharmacodynamic and pharmacokinetic features of some recently identified molecules with antioxidant property, such as salubrinal, guanabenz, N-acetyl cysteine, methylene blue, rapamycin, and naringenin, and on their potential use in future clinical studies. Expanding the models and the pharmacological screening for HSP disease is necessary to give an opportunity to patients and clinicians to test new molecules.
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Affiliation(s)
- Sentiljana Gumeni
- Department of Cell Biology and Biophysics, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Chiara Vantaggiato
- Laboratory of Molecular Biology, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, Italy
| | - Monica Montopoli
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padua, Italy
| | - Genny Orso
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padua, Italy
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5
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Musteikyte G, Ziaunys M, Smirnovas V. Methylene blue inhibits nucleation and elongation of SOD1 amyloid fibrils. PeerJ 2020; 8:e9719. [PMID: 32864220 PMCID: PMC7430317 DOI: 10.7717/peerj.9719] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/23/2020] [Indexed: 12/14/2022] Open
Abstract
Protein aggregation into highly-structured amyloid fibrils is linked to several neurodegenerative diseases. Such fibril formation by superoxide dismutase I (SOD1) is considered to be related to amyotrophic lateral sclerosis, a late-onset and fatal disorder. Despite much effort and the discovery of numerous anti-amyloid compounds, no effective cure or treatment is currently available. Methylene blue (MB), a phenothiazine dye, has been shown to modulate the aggregation of multiple amyloidogenic proteins. In this work we show its ability to inhibit both the spontaneous amyloid aggregation of SOD1 as well as elongation of preformed fibrils.
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Affiliation(s)
- Greta Musteikyte
- Department of Chemistry, University of Cambridge, Cambridge, United Kingdom.,Life Sciences Center, Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | - Mantas Ziaunys
- Life Sciences Center, Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | - Vytautas Smirnovas
- Life Sciences Center, Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
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6
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Buratti E. Targeting TDP-43 proteinopathy with drugs and drug-like small molecules. Br J Pharmacol 2020; 178:1298-1315. [PMID: 32469420 DOI: 10.1111/bph.15148] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 02/06/2023] Open
Abstract
Following the discovery of the involvement of the ribonucleoprotein TDP-43 in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), a major research focus has been to develop treatments that can prevent or alleviate these disease conditions. One pharmacological approach has been to use TDP-43-based disease models to test small molecules and drugs already known to have some therapeutic effect in a variety of neurodegenerative conditions. In parallel, various disease models have been used to perform high-throughput screens of drugs and small compound libraries. The aim of this review will be to provide a general overview of the compounds that have been described to alter pathological characteristics of TDP-43. These include expression levels, cytoplasmic mis-localization, post-translational modifications, cleavage, stress granule recruitment and aggregation. In parallel, this review will also address the use of compounds that modify the autophagic/proteasome systems that are known to target TDP-43 misfolding and aggregation. LINKED ARTICLES: This article is part of a themed issue on Neurochemistry in Japan. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.6/issuetoc.
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Affiliation(s)
- Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
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7
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8
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Preservation of neuromuscular function in symptomatic SOD1-G93A mice by peripheral infusion of methylene blue. Exp Neurol 2016; 285:96-107. [PMID: 27567739 DOI: 10.1016/j.expneurol.2016.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/31/2016] [Accepted: 08/23/2016] [Indexed: 12/14/2022]
Abstract
In mutant superoxide dismutase 1 (SOD1) mouse models of familial amyotrophic lateral sclerosis (fALS) some of the earliest signs of morphological and functional damage occur in the motor nerve terminals that innervate fast limb muscles. This study tested whether localized peripheral application of a protective drug could effectively preserve neuromuscular junctions in late-stage disease. Methylene blue (MB), which has mitochondria-protective properties, was infused via an osmotic pump into the anterior muscle compartment of one hind limb of late pre- symptomatic SOD1-G93A mice for ≥3weeks. When mice reached end-stage disease, peak twitch and tetanic contractions evoked by stimulation of the muscle nerve were measured in two anterior compartment muscles (tibialis anterior [TA] and extensor digitorum longus [EDL], both predominantly fast muscles). With 400μM MB in the infusion reservoir, muscles on the MB-infused side exhibited on average a ~100% increase in nerve-evoked contractile force compared to muscles on the contralateral non-infused side (p<0.01 for both twitch and tetanus in EDL and TA). Pairwise comparisons of endplate innervation also revealed a beneficial effect of MB infusion, with an average of 65% of endplates innervated in infused EDL, compared to only 35% on the non-infused side (p<0.01). Results suggested that MB's protective effects required an extracellular [MB] of ~1μM, were initiated peripherally (no evidence of retrograde transport into the spinal cord), and involved MB's reduced form. Thus peripherally-initiated actions of MB can help preserve neuromuscular structure and function in SOD1-G93A mice, even at late stages of disease.
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9
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Yang SH, Li W, Sumien N, Forster M, Simpkins JW, Liu R. Alternative mitochondrial electron transfer for the treatment of neurodegenerative diseases and cancers: Methylene blue connects the dots. Prog Neurobiol 2015; 157:273-291. [PMID: 26603930 DOI: 10.1016/j.pneurobio.2015.10.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/10/2015] [Accepted: 10/20/2015] [Indexed: 12/21/2022]
Abstract
Brain has exceptional high requirement for energy metabolism with glucose as the exclusive energy source. Decrease of brain energy metabolism and glucose uptake has been found in patients of Alzheimer's, Parkinson's and other neurodegenerative diseases, providing a clear link between neurodegenerative disorders and energy metabolism. On the other hand, cancers, including glioblastoma, have increased glucose uptake and rely on aerobic glycolysis for energy metabolism. The switch of high efficient oxidative phosphorylation to low efficient aerobic glycolysis pathway (Warburg effect) provides macromolecule for biosynthesis and proliferation. Current research indicates that methylene blue, a century old drug, can receive electron from NADH in the presence of complex I and donates it to cytochrome c, providing an alternative electron transfer pathway. Methylene blue increases oxygen consumption, decrease glycolysis, and increases glucose uptake in vitro. Methylene blue enhances glucose uptake and regional cerebral blood flow in rats upon acute treatment. In addition, methylene blue provides protective effect in neuron and astrocyte against various insults in vitro and in rodent models of Alzheimer's, Parkinson's, and Huntington's disease. In glioblastoma cells, methylene blue reverses Warburg effect by enhancing mitochondrial oxidative phosphorylation, arrests glioma cell cycle at s-phase, and inhibits glioma cell proliferation. Accordingly, methylene blue activates AMP-activated protein kinase, inhibits downstream acetyl-coA carboxylase and cyclin-dependent kinases. In summary, there is accumulating evidence providing a proof of concept that enhancement of mitochondrial oxidative phosphorylation via alternative mitochondrial electron transfer may offer protective action against neurodegenerative diseases and inhibit cancers proliferation.
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Affiliation(s)
- Shao-Hua Yang
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
| | - Wenjun Li
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Nathalie Sumien
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Michael Forster
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - James W Simpkins
- Department of Physiology and Pharmacology, Center for Neuroscience, Health Science Center, West Virginia University, Medical Center Drive, Morgantown, WV 26506, USA
| | - Ran Liu
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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Ryou MG, Choudhury GR, Li W, Winters A, Yuan F, Liu R, Yang SH. Methylene blue-induced neuronal protective mechanism against hypoxia-reoxygenation stress. Neuroscience 2015; 301:193-203. [PMID: 26047733 DOI: 10.1016/j.neuroscience.2015.05.064] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 05/13/2015] [Accepted: 05/27/2015] [Indexed: 12/17/2022]
Abstract
UNLABELLED Brain ischemia and reperfusion (I/R) injury occurs in various pathological conditions, but there is no effective treatment currently available in clinical practice. Methylene blue (MB) is a century-old drug with a newly discovered protective function in the ischemic stroke model. In the current investigation we studied the MB-induced neuroprotective mechanism focusing on stabilization and activation of hypoxia-inducible factor-1α (HIF-1α) in an in vitro oxygen and glucose deprivation (OGD)-reoxygenation model. METHODS HT22 cells were exposed to OGD (0.1% O2, 6h) and reoxygenation (21% O2, 24h). Cell viability was determined with the calcein AM assay. The dynamic change of intracellular O2 concentration was monitored by fluorescence lifetime imaging microscopy (FLTIM). Glucose uptake was quantified using the 2-[N-(7-Nitrobenz-2-Oxa-1,3-Diazol-4-yl)Amino]-2-Deoxy-d-Glucose (2-NBDG) assay. ATP concentration and glycolytic enzyme activity were examined by spectrophotometry. Protein content changes were measured by immunoblot: HIF-1α, prolyl hydroxylase 2 (PHD2), erythropoietin (EPO), Akt, mTOR, and PIP5K. The contribution of HIF-1α activation in the MB-induced neuroprotective mechanism was confirmed by blocking HIF-1α activation with 2-methoxyestradiol-2 (2-MeOE2) and by transiently transfecting constitutively active HIF-1α. RESULTS MB increases cell viability by about 50% vs. OGD control. Compared to the corresponding control, MB increases intracellular O2 concentration and glucose uptake as well as the activities of hexokinase and G-6-PDH, and ATP concentration. MB activates the EPO signaling pathway with a corresponding increase in HIF-1α. Phosphorylation of Akt was significantly increased with MB treatment followed by activation of the mTOR pathway. Importantly, we observed, MB increased nuclear translocation of HIF-1α vs. control (about three folds), which was shown by a ratio of nuclear:cytoplasmic HIF-1α protein content. CONCLUSION We conclude that MB protects the hippocampus-derived neuronal cells against OGD-reoxygenation injury by enhancing energy metabolism and increasing HIF-1α protein content accompanied by an activation of the EPO signaling pathway.
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Affiliation(s)
- M-G Ryou
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA; Cardiovascular Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA.
| | - G R Choudhury
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - W Li
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - A Winters
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - F Yuan
- Department of Neurosurgery, Beijing Tiantan Hospital, Beijing Neurosurgical Institute, Capital Medical University, Beijing 100050, China
| | - R Liu
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - S-H Yang
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA; Cardiovascular Research Institute, University of North Texas Health Science Center, Fort Worth, TX, USA; Department of Neurosurgery, Beijing Tiantan Hospital, Beijing Neurosurgical Institute, Capital Medical University, Beijing 100050, China.
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Hochgräfe K, Sydow A, Matenia D, Cadinu D, Könen S, Petrova O, Pickhardt M, Goll P, Morellini F, Mandelkow E, Mandelkow EM. Preventive methylene blue treatment preserves cognition in mice expressing full-length pro-aggregant human Tau. Acta Neuropathol Commun 2015; 3:25. [PMID: 25958115 PMCID: PMC4425867 DOI: 10.1186/s40478-015-0204-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 11/21/2022] Open
Abstract
Introduction Neurofibrillary tangles (NFT) composed of Tau are hallmarks of neurodegeneration in Alzheimer disease. Transgenic mice expressing full-length pro-aggregant human Tau (2N4R Tau-ΔK280, termed TauΔK) or its repeat domain (TauRD-ΔK280, TauRDΔK) develop a progressive Tau pathology with missorting, phosphorylation, aggregation of Tau, loss of synapses and functional deficits. Whereas TauRDΔK assembles into NFT concomitant with neuronal death, TauΔK accumulates into Tau pretangles without overt neuronal loss. Both forms cause a comparable cognitive decline (with onset at 10mo and 12mo, respectively), which is rescued upon switch-off of transgene expression. Since methylene blue (MB) is able to inhibit Tau aggregation in vitro, we investigated whether MB can prevent or rescue Tau-induced cognitive impairments in our mouse models. Both types of mice received MB orally using different preventive and therapeutic treatment protocols, initiated either before or after disease onset. The cognitive status of the mice was assessed by behavior tasks (open field, Morris water maze) to determine the most successful conditions for therapeutic intervention. Results Preventive and therapeutic MB application failed to avert or recover learning and memory deficits of TauRDΔK mice. Similarly, therapeutic MB treatment initiated after onset of cognitive impairments was ineffective in TauΔK mice. In contrast, preventive MB application starting before onset of functional deficits preserved cognition of TauΔK mice. Beside improved learning and memory, MB-treated TauΔK mice showed a strong decrease of insoluble Tau, a reduction of conformationally changed (MC1) and phosphorylated Tau species (AT180, PHF1) as well as an upregulation of protein degradation systems (autophagy and proteasome). This argues for additional pleiotropic effects of MB beyond its properties as Tau aggregation inhibitor. Conclusions Our data support the use of Tau aggregation inhibitors as potential drugs for the treatment of AD and other tauopathies and highlights the need for preventive treatment before onset of cognitive impairments. Electronic supplementary material The online version of this article (doi:10.1186/s40478-015-0204-4) contains supplementary material, which is available to authorized users.
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12
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Buratti E. Functional Significance of TDP-43 Mutations in Disease. ADVANCES IN GENETICS 2015; 91:1-53. [DOI: 10.1016/bs.adgen.2015.07.001] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Budini M, Baralle FE, Buratti E. Targeting TDP-43 in neurodegenerative diseases. Expert Opin Ther Targets 2014; 18:617-32. [DOI: 10.1517/14728222.2014.896905] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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14
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Guerrero-Muñoz MJ, Castillo-Carranza DL, Kayed R. Therapeutic approaches against common structural features of toxic oligomers shared by multiple amyloidogenic proteins. Biochem Pharmacol 2014; 88:468-78. [PMID: 24406245 DOI: 10.1016/j.bcp.2013.12.023] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 12/18/2013] [Accepted: 12/19/2013] [Indexed: 02/03/2023]
Abstract
Impaired proteostasis is one of the main features of all amyloid diseases, which are associated with the formation of insoluble aggregates from amyloidogenic proteins. The aggregation process can be caused by overproduction or poor clearance of these proteins. However, numerous reports suggest that amyloid oligomers are the most toxic species, rather than insoluble fibrillar material, in Alzheimer's, Parkinson's, and Prion diseases, among others. Although the exact protein that aggregates varies between amyloid disorders, they all share common structural features that can be used as therapeutic targets. In this review, we focus on therapeutic approaches against shared features of toxic oligomeric structures and future directions.
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Affiliation(s)
- Marcos J Guerrero-Muñoz
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Diana L Castillo-Carranza
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA.
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15
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Liu YC, Chiang PM, Tsai KJ. Disease animal models of TDP-43 proteinopathy and their pre-clinical applications. Int J Mol Sci 2013; 14:20079-111. [PMID: 24113586 PMCID: PMC3821604 DOI: 10.3390/ijms141020079] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/13/2013] [Accepted: 09/18/2013] [Indexed: 12/13/2022] Open
Abstract
Frontotemperal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) are two common neurodegenerative diseases. TDP-43 is considered to be a major disease protein in FTLD/ALS, but it’s exact role in the pathogenesis and the effective treatments remains unknown. To address this question and to determine a potential treatment for FTLD/ALS, the disease animal models of TDP-43 proteinopathy have been established. TDP-43 proteinopathy is the histologic feature of FTLD/ALS and is associated with disease progression. Studies on the disease animal models with TDP-43 proteinopathy and their pre-clinical applications are reviewed and summarized. Through these disease animal models, parts of TDP-43 functions in physiological and pathological conditions will be better understood and possible treatments for FTLD/ALS with TDP-43 proteinopathy may be identified for possible clinical applications in the future.
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Affiliation(s)
- Yu-Chih Liu
- Institute of Clinical Medicine, National Cheng Kung University, Tainan 704, Taiwan; E-Mails: (Y.-C.L.); (P.-M.C.)
- Institute of Basic Medical Science, National Cheng Kung University, Tainan 704, Taiwan
| | - Po-Min Chiang
- Institute of Clinical Medicine, National Cheng Kung University, Tainan 704, Taiwan; E-Mails: (Y.-C.L.); (P.-M.C.)
- Institute of Basic Medical Science, National Cheng Kung University, Tainan 704, Taiwan
| | - Kuen-Jer Tsai
- Institute of Clinical Medicine, National Cheng Kung University, Tainan 704, Taiwan; E-Mails: (Y.-C.L.); (P.-M.C.)
- Institute of Basic Medical Science, National Cheng Kung University, Tainan 704, Taiwan
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +886-6-235-3535 (ext. 4254); Fax: +886-6-275-8731
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16
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McGoldrick P, Joyce PI, Fisher EMC, Greensmith L. Rodent models of amyotrophic lateral sclerosis. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1832:1421-36. [PMID: 23524377 DOI: 10.1016/j.bbadis.2013.03.012] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 03/11/2013] [Accepted: 03/12/2013] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterised by the degeneration of upper and lower motor neurons. Recent advances in our understanding of some of the genetic causes of ALS, such as mutations in SOD1, TARDBP, FUS and VCP have led to the generation of rodent models of the disease, as a strategy to help our understanding of the pathophysiology of ALS and to assist in the development of therapeutic strategies. This review provides detailed descriptions of TDP-43, FUS and VCP models of ALS, and summarises potential therapeutics which have been recently trialled in rodent models of the disease. This article is part of a Special Issue entitled: Animal Models of Disease.
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Affiliation(s)
- Philip McGoldrick
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, WC1N 3BG, UK.
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17
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Abstract
Dysfunctions at the level of RNA processing have recently been shown to play a fundamental role in the pathogenesis of many neurodegenerative diseases. Several proteins responsible for these dysfunctions (TDP-43, FUS/TLS, and hnRNP A/Bs) belong to the nuclear class of heterogeneous ribonucleoproteins (hnRNPs) that predominantly function as general regulators of both coding and noncoding RNA metabolism. The discovery of the importance of these factors in mediating neuronal death has represented a major paradigmatic shift in our understanding of neurodegenerative processes. As a result, these discoveries have also opened the way toward novel biomolecular screening approaches in our search for therapeutic options. One of the major hurdles in this search is represented by the correct identification of the most promising targets to be prioritized. These may include aberrant aggregation processes, protein-protein interactions, RNA-protein interactions, or specific cellular pathways altered by disease. In this review, we discuss these four major options together with their various advantages and drawbacks.
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Affiliation(s)
- Maurizio Romano
- 1Department of Life Sciences, University of Trieste, Trieste, Italy
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18
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Yip PK, Pizzasegola C, Gladman S, Biggio ML, Marino M, Jayasinghe M, Ullah F, Dyall SC, Malaspina A, Bendotti C, Michael-Titus A. The omega-3 fatty acid eicosapentaenoic acid accelerates disease progression in a model of amyotrophic lateral sclerosis. PLoS One 2013; 8:e61626. [PMID: 23620776 PMCID: PMC3631166 DOI: 10.1371/journal.pone.0061626] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/12/2013] [Indexed: 12/14/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive fatal neurodegenerative disease characterised by loss of motor neurons that currently has no cure. Omega-3 polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA), have many health benefits including neuroprotective and myoprotective potential. We tested the hypothesis that a high level of dietary EPA could exert beneficial effects in ALS. The dietary exposure to EPA (300 mg/kg/day) in a well-established mouse model of ALS expressing the G93A superoxide dismutase 1 (SOD1) mutation was initiated at a pre-symptomatic or symptomatic stage, and the disease progression was monitored until the end stage. Daily dietary EPA exposure initiated at the disease onset did not significantly alter disease presentation and progression. In contrast, EPA treatment initiated at the pre-symptomatic stage induced a significantly shorter lifespan. In a separate group of animals sacrificed before the end stage, the tissue analysis showed that the vacuolisation detected in G93A-SOD1 mice was significantly increased by exposure to EPA. Although EPA did not alter motor neurone loss, EPA reversed the significant increase in activated microglia and the astrocytic activation seen in G93A-SOD1 mice. The microglia in the spinal cord of G93A-SOD1 mice treated with EPA showed a significant increase in 4-hydroxy-2-hexenal, a highly toxic aldehydic oxidation product of omega-3 fatty acids. These data show that dietary EPA supplementation in ALS has the potential to worsen the condition and accelerate the disease progression. This suggests that great caution should be exerted when considering dietary omega-3 fatty acid supplements in ALS patients.
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Affiliation(s)
- Ping K. Yip
- Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Chiara Pizzasegola
- Department Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri-IRCCS, Milano, Italy
| | - Stacy Gladman
- Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Maria Luigia Biggio
- Department Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri-IRCCS, Milano, Italy
| | - Marianna Marino
- Department Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri-IRCCS, Milano, Italy
| | - Maduka Jayasinghe
- Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Farhan Ullah
- Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Simon C. Dyall
- Blizard Institute, Queen Mary University of London, London, United Kingdom
- Department of Life Sciences, University of Roehampton, London, United Kingdom
| | - Andrea Malaspina
- Blizard Institute, Queen Mary University of London, London, United Kingdom
- North-East London and Essex MND Care Centre, Royal London Hospital, London, United Kingdom
| | - Caterina Bendotti
- Department Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri-IRCCS, Milano, Italy
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19
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Vaccaro A, Patten SA, Aggad D, Julien C, Maios C, Kabashi E, Drapeau P, Parker JA. Pharmacological reduction of ER stress protects against TDP-43 neuronal toxicity in vivo. Neurobiol Dis 2013; 55:64-75. [PMID: 23567652 DOI: 10.1016/j.nbd.2013.03.015] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 02/20/2013] [Accepted: 03/26/2013] [Indexed: 01/09/2023] Open
Abstract
C. elegans and D. rerio expressing mutant TAR DNA Binding Protein 43 (TDP-43) are powerful in vivo animal models for the genetics and pharmacology of amyotrophic lateral sclerosis (ALS). Using these small-animal models of ALS, we previously identified methylene blue (MB) as a potent suppressor of TDP-43 toxicity. Consequently here we investigated how MB might exert its neuroprotective properties and found that it acts through reduction of the endoplasmic reticulum (ER) stress response. We tested other compounds known to be active in the ER unfolded protein response in worms and zebrafish expressing mutant human TDP-43 (mTDP-43). We identified three compounds: salubrinal, guanabenz and a new structurally related compound phenazine, which also reduced paralysis, neurodegeneration and oxidative stress in our mTDP-43 models. Using C. elegans genetics, we showed that all four compounds act as potent suppressors of mTDP-43 toxicity through reduction of the ER stress response. Interestingly, these compounds operate through different branches of the ER unfolded protein pathway to achieve a common neuroprotective action. Our results indicate that protein-folding homeostasis in the ER is an important target for therapeutic development in ALS and other TDP-43-related neurodegenerative diseases.
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Abstract
Frontotemporal dementia (FTD) is a common dementia syndrome in patients under the age of 65 years with many features overlapping with amyotrophic lateral sclerosis (ALS). The link between FTD and ALS has been strengthened by the discovery that a hexanucleotide repeat expansion in a non-coding region of the C9ORF72 gene causes both familial and sporadic types of these two diseases. As we begin to understand the pathophysiological mechanisms by which this mutation leads to FTD and ALS (c9FTD/ALS), new targets for disease-modifying therapies will likely be unveiled. Putative C9ORF72 expansion pathogenic mechanisms include loss of C9ORF72 protein function, sequestration of nucleic acid binding proteins due to expanded hexanucleotide repeats, or a combination of the two. New animal models and other research tools informed by work in other repeat expansion neurodegenerative diseases such as the spinocerebellar ataxias will help to elucidate the mechanisms of C9ORF72-mediated disease. Similarly, re-examining previous studies of drugs developed to treat ALS in light of this new mutation may identify novel FTD treatments. Ultimately, research consortiums incorporating animal models and well-characterized clinical populations will be necessary to fully understand the natural history of the c9FTD/ALS clinical phenotypes and identify biomarkers and therapeutic agents that can cure the most common form of genetically determined FTD and ALS.
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Affiliation(s)
- Sharon J Sha
- University of California, San Francisco, Memory and Aging Center, Box 1207, San Francisco, CA 94143-1207, USA
| | - Adam Boxer
- University of California, San Francisco, Memory and Aging Center, Box 1207, San Francisco, CA 94143-1207, USA
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21
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Dibaj P, Zschüntzsch J, Steffens H, Scheffel J, Göricke B, Weishaupt JH, Le Meur K, Kirchhoff F, Hanisch UK, Schomburg ED, Neusch C. Influence of methylene blue on microglia-induced inflammation and motor neuron degeneration in the SOD1(G93A) model for ALS. PLoS One 2012; 7:e43963. [PMID: 22952827 PMCID: PMC3428282 DOI: 10.1371/journal.pone.0043963] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2011] [Accepted: 07/27/2012] [Indexed: 11/18/2022] Open
Abstract
Mutations in SOD1 cause hereditary variants of the fatal motor neuron disease amyotrophic lateral sclerosis (ALS). Pathophysiology of the disease is non-cell-autonomous, with toxicity deriving also from glia. In particular, microglia contribute to disease progression. Methylene blue (MB) inhibits the effect of nitric oxide, which mediates microglial responses to injury. In vivo 2P-LSM imaging was performed in ALS-linked transgenic SOD1(G93A) mice to investigate the effect of MB on microglia-mediated inflammation in the spinal cord. Local superfusion of the lateral spinal cord with MB inhibited the microglial reaction directed at a laser-induced axon transection in control and SOD1(G93A) mice. In vitro, MB at high concentrations inhibited cytokine and chemokine release from microglia of control and advanced clinical SOD1(G93A) mice. Systemic MB-treatment of SOD1(G93A) mice at early preclinical stages significantly delayed disease onset and motor dysfunction. However, an increase of MB dose had no additional effect on disease progression; this was unexpected in view of the local anti-inflammatory effects. Furthermore, in vivo imaging of systemically MB-treated mice also showed no alterations of microglia activity in response to local lesions. Thus although systemic MB treatment had no effect on microgliosis, instead, its use revealed an important influence on motor neuron survival as indicated by an increased number of lumbar anterior horn neurons present at the time of disease onset. Thus, potentially beneficial effects of locally applied MB on inflammatory events contributing to disease progression could not be reproduced in SOD1(G93A) mice via systemic administration, whereas systemic MB application delayed disease onset via neuroprotection.
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Affiliation(s)
- Payam Dibaj
- Max-Planck-Institute for Experimental Medicine, Göttingen, Germany.
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22
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Vaccaro A, Patten SA, Ciura S, Maios C, Therrien M, Drapeau P, Kabashi E, Parker JA. Methylene blue protects against TDP-43 and FUS neuronal toxicity in C. elegans and D. rerio. PLoS One 2012; 7:e42117. [PMID: 22848727 PMCID: PMC3407135 DOI: 10.1371/journal.pone.0042117] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 07/02/2012] [Indexed: 12/12/2022] Open
Abstract
The DNA/RNA-binding proteins TDP-43 and FUS are found in protein aggregates in a growing number of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and related dementia, but little is known about the neurotoxic mechanisms. We have generated Caenorhabditis elegans and zebrafish animal models expressing mutant human TDP-43 (A315T or G348C) or FUS (S57Δ or R521H) that reflect certain aspects of ALS including motor neuron degeneration, axonal deficits, and progressive paralysis. To explore the potential of our humanized transgenic C. elegans and zebrafish in identifying chemical suppressors of mutant TDP-43 and FUS neuronal toxicity, we tested three compounds with potential neuroprotective properties: lithium chloride, methylene blue and riluzole. We identified methylene blue as a potent suppressor of TDP-43 and FUS toxicity in both our models. Our results indicate that methylene blue can rescue toxic phenotypes associated with mutant TDP-43 and FUS including neuronal dysfunction and oxidative stress.
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Affiliation(s)
- Alexandra Vaccaro
- Université de Montréal Hospital Research Centre, Montréal, Québec, Canada
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- Centre of Excellence in Neuromics, Université de Montréal, Montréal, Canada
| | - Shunmoogum A. Patten
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- Centre of Excellence in Neuromics, Université de Montréal, Montréal, Canada
| | - Sorana Ciura
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- Centre of Excellence in Neuromics, Université de Montréal, Montréal, Canada
| | - Claudia Maios
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
| | - Martine Therrien
- Université de Montréal Hospital Research Centre, Montréal, Québec, Canada
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- Centre of Excellence in Neuromics, Université de Montréal, Montréal, Canada
| | - Pierre Drapeau
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- Centre of Excellence in Neuromics, Université de Montréal, Montréal, Canada
| | - Edor Kabashi
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- * E-mail: (EK); (JAP)
| | - J. Alex Parker
- Université de Montréal Hospital Research Centre, Montréal, Québec, Canada
- Département de pathologie et biologie cellulaire and Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Canada
- Centre of Excellence in Neuromics, Université de Montréal, Montréal, Canada
- * E-mail: (EK); (JAP)
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23
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Buratti E, Baralle FE. TDP-43: gumming up neurons through protein-protein and protein-RNA interactions. Trends Biochem Sci 2012; 37:237-47. [PMID: 22534659 DOI: 10.1016/j.tibs.2012.03.003] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 03/02/2012] [Accepted: 03/08/2012] [Indexed: 12/11/2022]
Abstract
Since the discovery that 43 kDa TAR DNA binding protein (TDP-43) is involved in neurodegeneration, studies of this protein have focused on the global effects of TDP-43 expression modulation on cell metabolism and survival. The major difficulty with these global searches, which can yield hundreds to thousands of variations in gene expression level and/or mRNA isoforms, is our limited ability to separate specific TDP-43 effects from secondary dysregulations occurring at the gene expression and various mRNA processing steps. In this review, we focus on two biochemical properties of TDP-43: its ability to bind RNA and its protein-protein interactions. In particular, we overview how these two properties may affect potentially very important processes for the pathology, from the autoregulation of TDP-43 to aggregation in the cytoplasmic/nuclear compartments.
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Affiliation(s)
- Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy
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