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Furuta M, Arii S, Umeda H, Matsukawa R, Shizu K, Kaji H, Kawashima SA, Hori Y, Tomita T, Sohma Y, Mitsunuma H, Kanai M. Leuco Ethyl Violet as Self-Activating Prodrug Photocatalyst for In Vivo Amyloid-Selective Oxygenation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2401346. [PMID: 38689504 DOI: 10.1002/advs.202401346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/02/2024] [Indexed: 05/02/2024]
Abstract
Aberrant aggregates of amyloid-β (Aβ) and tau protein (tau), called amyloid, are related to the etiology of Alzheimer disease (AD). Reducing amyloid levels in AD patients is a potentially effective approach to the treatment of AD. The selective degradation of amyloids via small molecule-catalyzed photooxygenation in vivo is a leading approach; however, moderate catalyst activity and the side effects of scalp injury are problematic in prior studies using AD model mice. Here, leuco ethyl violet (LEV) is identified as a highly active, amyloid-selective, and blood-brain barrier (BBB)-permeable photooxygenation catalyst that circumvents all of these problems. LEV is a redox-sensitive, self-activating prodrug catalyst; self-oxidation of LEV through a hydrogen atom transfer process under photoirradiation produces catalytically active ethyl violet (EV) in the presence of amyloid. LEV effectively oxygenates human Aβ and tau, suggesting the feasibility for applications in humans. Furthermore, a concept of using a hydrogen atom as a caging group of a reactive catalyst functional in vivo is postulated. The minimal size of the hydrogen caging group is especially useful for catalyst delivery to the brain through BBB.
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Affiliation(s)
- Masahiro Furuta
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Suguru Arii
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Hiroki Umeda
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Ryota Matsukawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Katsuyuki Shizu
- Institute for Chemical Research, Kyoto University, Kyoto, 611-0011, Japan
| | - Hironori Kaji
- Institute for Chemical Research, Kyoto University, Kyoto, 611-0011, Japan
| | - Shigehiro A Kawashima
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yukiko Hori
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Taisuke Tomita
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Youhei Sohma
- School of Pharmaceutical Sciences, Wakayama Medical University, Wakayama, 640-8156, Japan
| | - Harunobu Mitsunuma
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- PRESTO, JST, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Motomu Kanai
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
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Hakeem MJ, Khan JM, Malik A, Husain FM, Alresaini SM, Ahmad A, Alam P. Molecular insight into the modulation of ovalbumin fibrillation by allura red dye at acidic pH. Int J Biol Macromol 2023; 230:123254. [PMID: 36641020 DOI: 10.1016/j.ijbiomac.2023.123254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 01/08/2023] [Accepted: 01/09/2023] [Indexed: 01/13/2023]
Abstract
The synthetic food additive dye induces amyloid fibrillation has many implications in the laboratory and industries. The effect of Allura red (AR), on the fibrillation of ovalbumin (Ova) at pH 2.0 was investigated. The influence of salt and pH was also seen on AR-induced Ova aggregation. We have used several spectroscopic and microscopy techniques to characterize the changes. The turbidity data suggest that concentrations above 0.05 mM of AR induce aggregation, and the size of aggregates increased in response to AR concentration. The kinetics data showed that the AR induces Ova aggregation quickly without lag time. The aggregates induced by AR have amyloid-like aggregates confirmed by far-UV CD and TEM. NaCl has very marginal effects in AR-induced aggregation. The turbidity results clearly state that Ova is not forming aggregates with pH above 4.0 due to electrostatic repulsion. However, Ova forms bigger aggregates in the presence of 0.5 mM AR at a pH below 4.0. These spectroscopic data suggest that the amyloid fibrillation that occurs in Ova is due to electrostatic and hydrophobic interaction. The amyloid fibrillation induced by AR dye in protein should be taken seriously for food safety purposes.
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Affiliation(s)
- Mohammed J Hakeem
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, 2460, Riyadh, 11451, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, 2460, Riyadh, 11451, Saudi Arabia.
| | - Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Fohad Mabood Husain
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, 2460, Riyadh, 11451, Saudi Arabia
| | | | - Aqeel Ahmad
- Department of Medical Biochemistry, College of Medicine, Shaqra University, Shaqra 11961, Saudi Arabia
| | - Prawez Alam
- Department of Pharmacognosy, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
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3
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Bopardikar M, Koti Ainavarapu SR, Hosur RV. Pyrogallol, Corilagin and Chebulagic acid target the "fuzzy coat" of alpha-synuclein to inhibit the fibrillization of the protein. RSC Adv 2022; 12:35770-35777. [PMID: 36545068 PMCID: PMC9749937 DOI: 10.1039/d2ra04358k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 10/13/2022] [Indexed: 12/15/2022] Open
Abstract
The accumulation of the intrinsically disordered protein alpha-synuclein (αSyn) in the form of insoluble fibrillar aggregates in the central nervous system is linked to a variety of neurodegenerative disorders such as Parkinson's disease, Lewy body dementia, and multiple system atrophy. Here we show that Pyrogallol, Corilagin and Chebulagic acid, compounds containing a different number of catechol rings, are independently capable of delaying and reducing the extent of αSyn fibrillization. The efficiency of inhibition was found to correlate with the number of catechol rings. Further, our NMR studies reveal that these compounds interact with the N-terminal region of αSyn which is unstructured even in the fibrillar form of the protein and is known as the "fuzzy coat" of fibrils. Thus, Corilagin and Chebulagic acid target the fuzzy coat of αSyn and not the amyloid core which is a common target for the inhibition of protein fibrillization. Our results indicate that the N-terminus also plays a key role in the fibrillization of αSyn.
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Affiliation(s)
- Mandar Bopardikar
- Department of Chemical Sciences, Tata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai 400005India
| | - Sri Rama Koti Ainavarapu
- Department of Chemical Sciences, Tata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai 400005India
| | - Ramakrishna V. Hosur
- UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Kalina CampusSantacruzMumbai 400098India
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Min JO, Strohäker T, Jeong BC, Zweckstetter M, Lee SJ. Chicago sky blue 6B inhibits α-synuclein aggregation and propagation. Mol Brain 2022; 15:27. [PMID: 35346306 PMCID: PMC8962151 DOI: 10.1186/s13041-022-00913-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/17/2022] [Indexed: 11/10/2022] Open
Abstract
Abnormal deposition of α-synuclein aggregates in Lewy bodies and Lewy neurites is the hallmark lesion in Parkinson’s disease (PD). These aggregates, thought to be the culprit of disease pathogenesis, spread throughout the brain as the disease progresses. Agents that inhibit α-synuclein aggregation and/or spread of aggregates would thus be candidate disease-modifying drugs. Here, we found that Chicago sky blue 6B (CSB) may be such a drug, showing that it inhibits α-synuclein aggregation and cell-to-cell propagation in both in vitro and in vivo models of synucleinopathy. CSB inhibited the fibrillation of α-synuclein in a concentration-dependent manner through direct binding to the N-terminus of α-synuclein. Furthermore, both seeded polymerization and cell-to-cell propagation of α-synuclein were inhibited by CSB treatment. Notably, CSB alleviated behavioral deficits and neuropathological features, such as phospho-α-synuclein and astrogliosis, in A53T α-synuclein transgenic mice. These results indicate that CSB directly binds α-synuclein and inhibits its aggregation, thereby blocking α-synuclein cell-to-cell propagation.
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Affiliation(s)
- Joo-Ok Min
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, Republic of Korea
| | - Timo Strohäker
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Byung-Chul Jeong
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, Republic of Korea.,Nutritional Sciences and Toxicology Department, University of California Berkeley, Berkeley, USA
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany.,Department for NMR-Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany
| | - Seung-Jae Lee
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, Republic of Korea.
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Wang F, Wang Y, Jiang L, Wang W, Sang J, Wang X, Lu F, Liu F. The food additive fast green FCF inhibits α-synuclein aggregation, disassembles mature fibrils and protects against amyloid-induced neurotoxicity. Food Funct 2021; 12:5465-5477. [PMID: 33997868 DOI: 10.1039/d0fo03301d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
α-Synuclein (α-syn) aggregates into cytotoxic amyloid fibrils, which are recognized as the defining neuropathological feature of Parkinson's disease (PD). Therefore, inhibiting α-syn fibrillogenesis and disrupting the preformed fibrils are both considered attractive strategies to cure PD. We discovered that a safe food additive, fast green FCF, is capable of inhibiting α-synuclein fibrillogenesis and reducing the related cytotoxicity. Thioflavin T fluorescence assays demonstrated that fast green FCF could inhibit the fibrillogenesis α-synuclein. In the presence of 100 μM fast green FCF, amorphous aggregates were formed and observed by atomic force microscopy. Toxicity assays in cell cultures revealed that fast green FCF significantly reduced the cytotoxicity of α-syn. Molecular dynamics simulations revealed the potential mechanism of the interactions between fast green FCF and α-synuclein. Fast green FCF greatly disrupted the α-synuclein pentamer and reduced the β-sheet content by reducing both nonpolar and polar interactions. Furthermore, two binding sites were identified, named region I (Y39-K45) and region II (H50-Q62). Our data reveal that electrostatic interactions, hydrogen bonds, and π-π interactions synergistically contribute to the binding of fast green FCF to the α-synuclein pentamer. These results indicate that fast green FCF is a candidate prototype for the development of drugs against the aggregation of amyloid fibrils in PD.
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Affiliation(s)
- Fenghua Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Ying Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Luying Jiang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Wenqian Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Jingcheng Sang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Xinyu Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Fuping Lu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
| | - Fufeng Liu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education; Tianjin Key Laboratory of Industrial Microbiology; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P. R. China.
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Mukimin A, Vistanty H, Zen N. Hybrid advanced oxidation process (HAOP) as highly efficient and powerful treatment for complete demineralization of antibiotics. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116728] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Advances in the development of imaging probes and aggregation inhibitors for alpha-synuclein. Acta Pharmacol Sin 2020; 41:483-498. [PMID: 31586134 PMCID: PMC7470848 DOI: 10.1038/s41401-019-0304-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 08/29/2019] [Indexed: 12/20/2022] Open
Abstract
Abnormal protein aggregation has been linked to many neurodegenerative diseases, including Parkinson’s disease (PD). The main pathological hallmark of PD is the formation of Lewy bodies (LBs) and Lewy neurites, both of which contain the presynaptic protein alpha-synuclein (α-syn). Under normal conditions, native α-syn exists in a soluble unfolded state but undergoes misfolding and aggregation into toxic aggregates under pathological conditions. Toxic α-syn species, especially oligomers, can cause oxidative stress, membrane penetration, synaptic and mitochondrial dysfunction, as well as other damage, leading to neuronal death and eventually neurodegeneration. Early diagnosis and treatments targeting PD pathogenesis are urgently needed. Given its critical role in PD, α-syn is an attractive target for the development of both diagnostic tools and effective therapeutics. This review summarizes the progress toward discovering imaging probes and aggregation inhibitors for α-syn. Relevant strategies and techniques in the discovery of α-syn-targeted drugs are also discussed.
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Liu F, Wang Y, Sang J, Wei W, Zhao W, Chen B, Zhao F, Jia L, Lu F. Brazilin Inhibits α-Synuclein Fibrillogenesis, Disrupts Mature Fibrils, and Protects against Amyloid-Induced Cytotoxicity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:11769-11777. [PMID: 31575115 DOI: 10.1021/acs.jafc.9b04558] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The inhibitory effect of brazilin against α-synuclein (α-syn) fibrillogenesis, disruption effect against mature fibrils, and the following cytotoxicity were examined by systematical biochemical, biophysical, cellular biological, and molecular simulation experiments. It is found that brazilin inhibited α-syn fibrillogenesis and disrupted the performed fibrils with a concentration-dependent manner. Moreover, cellular experimental data showed that brazilin effectively reduced the cytotoxicity induced by α-syn aggregates. Finally, molecular dynamics simulations were performed to explore the interactions between brazilin and α-syn pentamer. It is found that brazilin directly interacts with α-syn pentamer, and the hydrophobic interactions are favorable for brazilin binding with the α-syn pentamer, while the electrostatic part provides adverse effects. Three binding regions were identified to inhibit α-syn fibrillogenesis or disrupt the preformed aggregates. Furthermore, six important residues (i.e., G51, V52, A53, E61, V66, and K80) of α-syn were also identified. We expected that brazilin is an effective agent against α-syn fibrillogenesis and associated cytotoxicity.
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Affiliation(s)
- Fufeng Liu
- Key Laboratory of Industrial Fermentation Microbiology , Ministry of Education , Tianjin 300457 , P. R. China
| | | | | | | | | | | | | | | | - Fuping Lu
- Key Laboratory of Industrial Fermentation Microbiology , Ministry of Education , Tianjin 300457 , P. R. China
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Bopardikar M, Bhattacharya A, Rao Kakita VM, Rachineni K, Borde LC, Choudhary S, Koti Ainavarapu SR, Hosur RV. Triphala inhibits alpha-synuclein fibrillization and their interaction study by NMR provides insights into the self-association of the protein. RSC Adv 2019; 9:28470-28477. [PMID: 35529629 PMCID: PMC9071048 DOI: 10.1039/c9ra05551g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 08/31/2019] [Indexed: 11/21/2022] Open
Abstract
The process of assembly and accumulation of the intrinsically disordered protein (IDP), alpha-synuclein (αSyn) into amyloid fibrils is a pathogenic process leading to several neurodegenerative disorders such as Parkinson's disease, multiple system atrophy and others. Although several molecules are known to inhibit αSyn fibrillization, the mechanism of inhibition is just beginning to emerge. Here, we report the inhibition of fibrillization of αSyn by Triphala, a herbal preparation in the traditional Indian medical system of Ayurveda. Triphala was found to be a rich source of polyphenols which are known to act as amyloid inhibitors. ThT fluorescence and TEM studies showed that Triphala inhibited the fibrillization of αSyn. However, it was observed that Triphala does not disaggregate preformed αSyn fibrils. Further, native-PAGE showed that Triphala reduces the propensity of αSyn to oligomerize during the lag phase of fibrillization. Our NMR results showed that certain stretches of residues in the N-terminal and NAC regions of αSyn play an anchor role in the self-association process of the protein, thereby providing mechanistic insights into the early events during αSyn fibrillization. Triphala inhibits αSyn self-association by interacting with anchoring regions which are responsible for αSyn oligomerization.![]()
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Affiliation(s)
- Mandar Bopardikar
- Department of Chemical Sciences
- Tata Institute of Fundamental Research
- Mumbai 400005
- India
| | - Anusri Bhattacharya
- UM-DAE Centre for Excellence in Basic Sciences
- University of Mumbai
- Kalina Campus
- Mumbai 400098
- India
| | - Veera Mohana Rao Kakita
- UM-DAE Centre for Excellence in Basic Sciences
- University of Mumbai
- Kalina Campus
- Mumbai 400098
- India
| | - Kavitha Rachineni
- UM-DAE Centre for Excellence in Basic Sciences
- University of Mumbai
- Kalina Campus
- Mumbai 400098
- India
| | - Lalit C. Borde
- Department of Biological Sciences
- Tata Institute of Fundamental Research
- Mumbai 400005
- India
| | - Sinjan Choudhary
- UM-DAE Centre for Excellence in Basic Sciences
- University of Mumbai
- Kalina Campus
- Mumbai 400098
- India
| | | | - Ramakrishna V. Hosur
- Department of Chemical Sciences
- Tata Institute of Fundamental Research
- Mumbai 400005
- India
- UM-DAE Centre for Excellence in Basic Sciences
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Schwab K, Frahm S, Horsley D, Rickard JE, Melis V, Goatman EA, Magbagbeolu M, Douglas M, Leith MG, Baddeley TC, Storey JMD, Riedel G, Wischik CM, Harrington CR, Theuring F. A Protein Aggregation Inhibitor, Leuco-Methylthioninium Bis(Hydromethanesulfonate), Decreases α-Synuclein Inclusions in a Transgenic Mouse Model of Synucleinopathy. Front Mol Neurosci 2018; 10:447. [PMID: 29375308 PMCID: PMC5767730 DOI: 10.3389/fnmol.2017.00447] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 12/21/2017] [Indexed: 12/13/2022] Open
Abstract
α-Synuclein (α-Syn) aggregation is a pathological feature of synucleinopathies, neurodegenerative disorders that include Parkinson's disease (PD). We have tested whether N,N,N',N'-tetramethyl-10H-phenothiazine-3,7-diaminium bis(hydromethanesulfonate) (leuco-methylthioninium bis(hydromethanesulfonate); LMTM), a tau aggregation inhibitor, affects α-Syn aggregation in vitro and in vivo. Both cellular and transgenic models in which the expression of full-length human α-Syn (h-α-Syn) fused with a signal sequence peptide to promote α-Syn aggregation were used. Aggregated α-Syn was observed following differentiation of N1E-115 neuroblastoma cells transfected with h-α-Syn. The appearance of aggregated α-Syn was inhibited by LMTM, with an EC50 of 1.1 μM, with minimal effect on h-α-Syn mRNA levels being observed. Two independent lines of mice (L58 and L62) transgenic for the same fusion protein accumulated neuronal h-α-Syn that, with aging, developed into fibrillary inclusions characterized by both resistance to proteinase K (PK)-cleavage and their ability to bind thiazin red. There was a significant decrease in α-Syn-positive neurons in multiple brain regions following oral treatment of male and female mice with LMTM administered daily for 6 weeks at 5 and 15 mg MT/kg. The early aggregates of α-Syn and the late-stage fibrillar inclusions were both susceptible to inhibition by LMTM, a treatment that also resulted in the rescue of movement and anxiety-related traits in these mice. The results suggest that LMTM may provide a potential disease modification therapy in PD and other synucleinopathies through the inhibition of α-Syn aggregation.
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Affiliation(s)
- Karima Schwab
- Institute of Pharmacology, Charite – Universitätsmedizin Berlin, Berlin, Germany
| | - Silke Frahm
- Institute of Pharmacology, Charite – Universitätsmedizin Berlin, Berlin, Germany
| | - David Horsley
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Janet E. Rickard
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Valeria Melis
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Elizabeth A. Goatman
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Mandy Magbagbeolu
- Institute of Pharmacology, Charite – Universitätsmedizin Berlin, Berlin, Germany
| | - Morag Douglas
- Department of Chemistry, University of Aberdeen, Aberdeen, United Kingdom
| | - Michael G. Leith
- Department of Chemistry, University of Aberdeen, Aberdeen, United Kingdom
| | - Thomas C. Baddeley
- Department of Chemistry, University of Aberdeen, Aberdeen, United Kingdom
- TauRx Therapeutics Ltd., Singapore, Singapore
| | - John M. D. Storey
- Department of Chemistry, University of Aberdeen, Aberdeen, United Kingdom
- TauRx Therapeutics Ltd., Singapore, Singapore
| | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Claude M. Wischik
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
- TauRx Therapeutics Ltd., Singapore, Singapore
| | - Charles R. Harrington
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
- TauRx Therapeutics Ltd., Singapore, Singapore
| | - Franz Theuring
- Institute of Pharmacology, Charite – Universitätsmedizin Berlin, Berlin, Germany
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