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Wang F, Chen Z, Zhou Q, Sun Q, Zheng N, Chen Z, Lin J, Li B, Li L. Implications of liquid-liquid phase separation and ferroptosis in Alzheimer's disease. Neuropharmacology 2024; 259:110083. [PMID: 39043267 DOI: 10.1016/j.neuropharm.2024.110083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 07/04/2024] [Accepted: 07/15/2024] [Indexed: 07/25/2024]
Abstract
Neuronal cell demise represents a prevalent occurrence throughout the advancement of Alzheimer's disease (AD). However, the mechanism of triggering the death of neuronal cells remains unclear. Its potential mechanisms include aggregation of soluble amyloid-beta (Aβ) to form insoluble amyloid plaques, abnormal phosphorylation of tau protein and formation of intracellular neurofibrillary tangles (NFTs), neuroinflammation, ferroptosis, oxidative stress, liquid-liquid phase separation (LLPS) and metal ion disorders. Among them, ferroptosis is an iron-dependent lipid peroxidation-driven cell death and emerging evidences have demonstrated the involvement of ferroptosis in the pathological process of AD. The sensitivity to ferroptosis is tightly linked to numerous biological processes. Moreover, emerging evidences indicate that LLPS has great impacts on regulating human health and diseases, especially AD. Soluble Aβ can undergo LLPS to form liquid-like droplets, which can lead to the formation of insoluble amyloid plaques. Meanwhile, tau has a high propensity to condensate via the mechanism of LLPS, which can lead to the formation of NFTs. In this review, we summarize the most recent advancements pertaining to LLPS and ferroptosis in AD. Our primary focus is on expounding the influence of Aβ, tau protein, iron ions, and lipid oxidation on the intricate mechanisms underlying ferroptosis and LLPS within the domain of AD pathology. Additionally, we delve into the intricate cross-interactions that occur between LLPS and ferroptosis in the context of AD. Our findings are expected to serve as a theoretical and experimental foundation for clinical research and targeted therapy for AD.
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Affiliation(s)
- Fuwei Wang
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China
| | - Zihao Chen
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China
| | - Qiong Zhou
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China
| | - Qiang Sun
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China
| | - Nan Zheng
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China
| | - Ziwen Chen
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China
| | - Jiantao Lin
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China.
| | - Baohong Li
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China.
| | - Li Li
- Dongguan Key Laboratory of Traditional Chinese Medicine and New Pharmaceutical Development, The Affiliated Dongguan Songshan Lake Central Hospital, School of Pharmacy, Guangdong Medical University, Dongguan, China.
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Liu H, Liu Z, Xiao J, Liu X, Jiang H, Wang X. Photo-induced Oriented Crystallization of Intracellular Nanocrystals Based on Phase Separation for Diagnostic Bioimaging and Analysis. Adv Healthc Mater 2024; 13:e2303248. [PMID: 38272459 DOI: 10.1002/adhm.202303248] [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: 09/25/2023] [Revised: 01/05/2024] [Indexed: 01/27/2024]
Abstract
Biomineral crystals form complex nonequilibrium structures based on the multistep nucleation theory, via transient amorphous precursors. However, the intricate nature of the biological system results in the inconsistent frequency of nucleation and crystallization, which making it problematic to obtain homogeneous nanocrystals, limits their application in biomedicine. Here, it is reported that homogeneous nanocrystals of photoinduced oriented crystallization with protein coronas are based on intracellular liquid-liquid phase separation for in situ analysis and mapping of surface-enhanced Raman spectroscopy (SERS). Near-infrared light promotes the formation of intracellular dense phases, accelerates the nucleation of gold atoms at secondary structure sites of proteins, and promotes the growth of crystals. Homogeneous gold nanocrystals with stable SERS signals can be used to analysis different cell cycles and acquire in situ molecular information of metastatic tumor cells. Of note are tag molecule is embedded in protein coronas of gold nanocrystals to enable the mapping of patient tumor tissue samples and the portable recognition of tumor cells. Thus, this study proposes a new strategy for biomineralization of intracellular homogeneous gold nanocrystals and its potential application.
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Affiliation(s)
- Hao Liu
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Zhiming Liu
- Guangdong Provincial Key Laboratory of Laser Life Science and Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou, 510631, P. R. China
| | - Jiang Xiao
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Xiaohui Liu
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Hui Jiang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Xuemei Wang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu, 210096, China
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3
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Lu X, Lu J, Li S, Feng S, Wang Y, Cui L. The Role of Liquid-Liquid Phase Separation in the Accumulation of Pathological Proteins: New Perspectives on the Mechanism of Neurodegenerative Diseases. Aging Dis 2024:AD.2024.0209. [PMID: 38739933 DOI: 10.14336/ad.2024.0209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/20/2024] [Indexed: 05/16/2024] Open
Abstract
It is widely accepted that living organisms form highly dynamic membrane-less organelles (MLOS) with various functions through phase separation, and the indispensable role that phase separation plays in the mechanisms of normal physiological functions and pathogenesis is gradually becoming clearer. Pathological aggregates, regarded as hallmarks of neurodegenerative diseases, have been revealed to be closely related to aberrant phase separation. Specific proteins are assembled into condensates and transform into insoluble inclusions through aberrant phase separation, contributing to the development of diseases. In this review, we present an overview of the progress of phase separation research, involving its biological mechanisms and the status of research in neurodegenerative diseases, focusing on five main disease-specific proteins, tau, TDP-43, FUS, α-Syn and HTT, and how exactly these proteins reside within dynamic liquid-like compartments and thus turn into solid deposits. Further studies will yield new perspectives for understanding the aggregation mechanisms and potential therapeutic strategies, and future research directions are anticipated.
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Affiliation(s)
- Xingyu Lu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Jiongtong Lu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Shengnan Li
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Sifan Feng
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yan Wang
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Lili Cui
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- The Marine Biomedical Research Institute of Guangdong, School of Ocean and Tropical Medicine, Guangdong Medical University, Zhanjiang, Guangdong, China
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4
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Padhi D, Baruah P, Ramesh M, Moorthy H, Govindaraju T. Hybrid molecules synergistically mitigate ferroptosis and amyloid-associated toxicities in Alzheimer's disease. Redox Biol 2024; 71:103119. [PMID: 38507972 PMCID: PMC10963859 DOI: 10.1016/j.redox.2024.103119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 02/22/2024] [Accepted: 03/07/2024] [Indexed: 03/22/2024] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the build-up of extracellular amyloid β (Aβ) plaques and intracellular neurofibrillary tangles (NFTs). Ferroptosis, an iron (Fe)-dependent form of cell death plays a significant role in the multifaceted AD pathogenesis through generation of reactive oxygen species (ROS), mitochondrial damage, lipid peroxidation, and reduction in glutathione peroxidase 4 (GPX4) enzyme activity and levels. Aberrant liquid-liquid phase separation (LLPS) of tau drives the growth and maturation of NFTs contributing to AD pathogenesis. In this study, we strategically combined the structural and functional properties of gallic acid (GA) and cyclic dipeptides (CDPs) to synthesize hybrid molecules that effectively target both ferroptosis and amyloid toxicity in AD. This innovative approach marks a paradigm shift from conventional therapeutic strategies. This is the first report of a synthetic small molecule (GCTR) that effectively combats ferroptosis, simultaneously restoring enzymatic activity and enhancing cellular levels of its master regulator, GPX4. Further, GCTR disrupts Fe3+-induced LLPS of tau, and aids in attenuation of abnormal tau fibrillization. The synergistic action of GCTR in combating both ferroptosis and amyloid toxicity, bolstered by GPX4 enhancement and modulation of Fe3+-induced tau LLPS, holds promise for the development of small molecule-based novel therapeutics for AD.
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Affiliation(s)
- Dikshaa Padhi
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Prayasee Baruah
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Madhu Ramesh
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Hariharan Moorthy
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Thimmaiah Govindaraju
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India.
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5
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Lee S, Kovacs GG. The Irony of Iron: The Element with Diverse Influence on Neurodegenerative Diseases. Int J Mol Sci 2024; 25:4269. [PMID: 38673855 PMCID: PMC11049980 DOI: 10.3390/ijms25084269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/07/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024] Open
Abstract
Iron accumulation in the brain is a common feature of many neurodegenerative diseases. Its involvement spans across the main proteinopathies involving tau, amyloid-beta, alpha-synuclein, and TDP-43. Accumulating evidence supports the contribution of iron in disease pathologies, but the delineation of its pathogenic role is yet challenged by the complex involvement of iron in multiple neurotoxicity mechanisms and evidence supporting a reciprocal influence between accumulation of iron and protein pathology. Here, we review the major proteinopathy-specific observations supporting four distinct hypotheses: (1) iron deposition is a consequence of protein pathology; (2) iron promotes protein pathology; (3) iron protects from or hinders protein pathology; and (4) deposition of iron and protein pathology contribute parallelly to pathogenesis. Iron is an essential element for physiological brain function, requiring a fine balance of its levels. Understanding of disease-related iron accumulation at a more intricate and systemic level is critical for advancements in iron chelation therapies.
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Affiliation(s)
- Seojin Lee
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON M5T 0S8, Canada;
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Gabor G. Kovacs
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON M5T 0S8, Canada;
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
- Edmond J. Safra Program in Parkinson’s Disease, Rossy Program for PSP Research and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON M5T 2S8, Canada
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Venkatramani A, Ashtam A, Panda D. EB1 Increases the Dynamics of Tau Droplets and Inhibits Tau Aggregation: Implications in Tauopathies. ACS Chem Neurosci 2024; 15:1219-1233. [PMID: 38445984 DOI: 10.1021/acschemneuro.3c00815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024] Open
Abstract
EB1, a microtubule plus end-tracking protein (+TIP), regulates microtubule dynamics. Recent evidence indicates cross-talk between EB proteins and tau, a microtubule-associated neuronal protein that is important for the growth and stability of microtubules. We investigated the interaction between tau and EB1 and the effect of binding of EB1 on tau function and aggregation. EB1 colocalized with tau in SH-SY5Y cells and coimmunoprecipitated with tau. Further, purified EB1 impaired the ability of adult tau to induce tubulin polymerization in vitro. EB1 bound to tau with a dissociation constant of 2.5 ± 0.7 μM. EB1 reduced heparin-induced tau aggregation with a half-maximal inhibitory concentration of 4.3 ± 0.2 μM, and increased the dynamics of tau in phase-separated droplets. The fluorescence recovery rate in tau droplets increased from 0.02 ± 0.01 to 0.07 ± 0.03 s-1, while the half-time of recovery decreased from 44.5 ± 14 to 13.5 ± 6 s in the presence of 8 μM EB1, suggesting a delay in the transition of tau from the soluble to aggregated form in tau liquid-liquid phase separation. EB1 decreased the rate of aggregation and increased the critical concentration of tau aggregation. Dynamic light scattering, atomic force microscopy, dot blot assays, and SDS-PAGE analysis showed that EB1 inhibited the formation of oligomers and higher-order aggregates of tau. The data suggest a novel role for EB1 as a regulator of tau function and aggregation, and the findings indicated the role of the EB family proteins in neuronal function and neurodegeneration.
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Affiliation(s)
- Anuradha Venkatramani
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Anvesh Ashtam
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Dulal Panda
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
- National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab 160062, India
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7
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Liu HN, Wang T, Hu JJ, Chen L, Shi X, Li YM, Luo SZ. The disordered protein SERF promotes α-Synuclein aggregation through liquid-liquid phase separation. J Biol Chem 2024; 300:105667. [PMID: 38272228 PMCID: PMC10877630 DOI: 10.1016/j.jbc.2024.105667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 12/26/2023] [Accepted: 12/28/2023] [Indexed: 01/27/2024] Open
Abstract
The aggregation of α-Synuclein (α-Syn) into amyloid fibrils is the hallmark of Parkinson's disease. Under stress or other pathological conditions, the accumulation of α-Syn oligomers is the main contributor to the cytotoxicity. A potential approach for treating Parkinson's disease involves preventing the accumulation of these α-Syn oligomers. In this study, we present a novel mechanism involving a conserved group of disorderly proteins known as small EDRK-rich factor (SERF), which promotes the aggregation of α-Syn through a cophase separation process. Using diverse methods like confocal microscopy, fluorescence recovery after photobleaching assays, solution-state NMR spectroscopy, and Western blot, we determined that the N-terminal domain of SERF1a plays a role in the interactions that occur during cophase separation. Within these droplets, α-Syn undergoes a gradual transformation from solid condensates to amyloid fibrils, while SERF1a is excluded from the condensates and dissolves into the solution. Notably, in vivo experiments show that SERF1a cophase separation with α-Syn significantly reduces the deposition of α-Syn oligomers and decreases its cellular toxicity under stress. These findings suggest that SERF1a accelerates the conversion of α-Syn from highly toxic oligomers to less toxic fibrils through cophase separation, thereby mitigating the biological damage of α-Syn aggregation.
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Affiliation(s)
- He-Ning Liu
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Ting Wang
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Jin-Jian Hu
- Key Lab of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China
| | - Long Chen
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Xiangyan Shi
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen, China.
| | - Yan-Mei Li
- Key Lab of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China.
| | - Shi-Zhong Luo
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China.
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8
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Fu Q, Zhang B, Chen X, Chu L. Liquid-liquid phase separation in Alzheimer's disease. J Mol Med (Berl) 2024; 102:167-181. [PMID: 38167731 DOI: 10.1007/s00109-023-02407-3] [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: 04/17/2023] [Revised: 11/26/2023] [Accepted: 12/04/2023] [Indexed: 01/05/2024]
Abstract
The pathological aggregation and misfolding of tau and amyloid-β play a key role in Alzheimer's disease (AD). However, the underlying pathological mechanisms remain unclear. Emerging evidences indicate that liquid-liquid phase separation (LLPS) has great impacts on regulating human health and diseases, especially neurodegenerative diseases. A series of studies have revealed the significance of LLPS in AD. In this review, we summarize the latest progress of LLPS in AD, focusing on the impact of metal ions, small-molecule inhibitors, and proteinaceous partners on tau LLPS and aggregation, as well as toxic oligomerization, the role of LLPS on amyloid-β (Aβ) aggregation, and the cross-interactions between amyloidogenic proteins in AD. Eventually, the fundamental methods and techniques used in LLPS study are introduced. We expect to present readers a deeper understanding of the relationship between LLPS and AD.
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Affiliation(s)
- Qinggang Fu
- Hepatic Surgery Center and Hubei Key Laboratory of Hepato-Pancreatic-Biliary Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Bixiang Zhang
- Hepatic Surgery Center and Hubei Key Laboratory of Hepato-Pancreatic-Biliary Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Xiaoping Chen
- Hepatic Surgery Center and Hubei Key Laboratory of Hepato-Pancreatic-Biliary Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Liang Chu
- Hepatic Surgery Center and Hubei Key Laboratory of Hepato-Pancreatic-Biliary Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.
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Satoh R, Weigand SD, Pham T, Ali F, Arani A, Senjem ML, Jack CR, Whitwell JL, Josephs KA. Magnetic Susceptibility in Progressive Supranuclear Palsy Variants, Parkinson's Disease, and Corticobasal Syndrome. Mov Disord 2023; 38:2282-2290. [PMID: 37772771 PMCID: PMC10840892 DOI: 10.1002/mds.29613] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 09/11/2023] [Indexed: 09/30/2023] Open
Abstract
BACKGROUND Previous studies have shown that magnetic susceptibility is increased in several subcortical regions in progressive supranuclear palsy (PSP). However, it is still unclear how subcortical and cortical susceptibilities vary across different PSP variants, Parkinson's disease (PD), and corticobasal syndrome (CBS). OBJECTIVE This study aims to clarify the susceptibility profiles in the subcortical and cortical regions in different PSP variants, PD, and CBS. METHODS Sixty-four patients, 20 PSP-Richardson syndrome (PSP-RS), 9 PSP-parkinsonism (PSP-P), 7 PSP-progressive gait freezing, 4 PSP-postural instability, 11 PD, and 13 CBS, and 20 cognitively normal control subjects underwent a 3-Tesla magnetic resonance imaging scan to reconstruct quantitative susceptibility maps. Region-of-interest analysis was performed to obtain susceptibility in several subcortical and cortical regions. Bayesian linear mixed effect models were used to estimate susceptibility within group and differences between groups. RESULTS In the subcortical regions, patients with PSP-RS and PSP-P showed greater susceptibility than control subjects in the pallidum, substantia nigra, red nucleus, and cerebellar dentate (P < 0.05). Patients with PSP-RS also showed greater susceptibility than patients with PSP-progressive gait freezing, PD, and CBS in the red nucleus and cerebellar dentate, and patients with PSP-P showed greater susceptibility than PD in the red nucleus. Patients with PSP-postural instability and CBS showed greater susceptibility than control subjects in the pallidum and substantia nigra. No significant differences were observed in any cortical region. CONCLUSIONS The PSP variants and CBS had different patterns of magnetic susceptibility in the subcortical regions. The findings will contribute to our understanding about iron profiles and pathophysiology of PSP and may provide a potential biomarker to differentiate PSP variants, PD, and CBS. © 2023 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Ryota Satoh
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Stephen D Weigand
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, 55905, USA
| | - Thu Pham
- Department of Radiology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Farwa Ali
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Arvin Arani
- Department of Radiology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Matthew L. Senjem
- Department of Radiology, Mayo Clinic, Rochester, MN, 55905, USA
- Department of Information Technology, Mayo Clinic, Rochester, MN, 55905, USA
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Li P, Chen J, Wang X, Su Z, Gao M, Huang Y. Liquid - liquid phase separation of tau: Driving forces, regulation, and biological implications. Neurobiol Dis 2023; 183:106167. [PMID: 37230179 DOI: 10.1016/j.nbd.2023.106167] [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: 03/26/2023] [Revised: 05/16/2023] [Accepted: 05/21/2023] [Indexed: 05/27/2023] Open
Abstract
The past 15 years have witnessed an explosion in the studies of biomolecular condensates that are implicated in numerous biological processes and play vital roles in human health and diseases. Recent findings demonstrate that the microtubule-associated protein tau forms liquid condensates through liquid-liquid phase separation (LLPS) in in vitro experiments using purified recombinant proteins and cell-based experiments. Although in vivo studies are lacking, liquid condensates have emerged as an important assembly state of physiological and pathological tau and LLPS can regulate the function of microtubules, mediate stress granule formation, and accelerate tau amyloid aggregation. In this review, we summarize recent advances in tau LLPS, aiming to unveiling the delicate interactions driving tau LLPS. We further discuss the association of tau LLPS with physiology and disease in the context of the sophisticated regulation of tau LLPS. Deciphering the mechanisms underlying tau LLPS and the liquid-to-solid transition enables rational design of molecules that inhibit or delay the formation of tau solid species, thus providing novel targeted therapeutic strategies for tauopathies.
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Affiliation(s)
- Ping Li
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Jingxin Chen
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Xi Wang
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Zhengding Su
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Meng Gao
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China.
| | - Yongqi Huang
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China.
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11
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Lee S, Martinez-Valbuena I, de Andrea CE, Villalba-Esparza M, Ilaalagan S, Couto B, Visanji NP, Lang AE, Kovacs GG. Cell-Specific Dysregulation of Iron and Oxygen Homeostasis as a Novel Pathophysiology in PSP. Ann Neurol 2023; 93:431-445. [PMID: 36309960 DOI: 10.1002/ana.26540] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 10/23/2022] [Accepted: 10/25/2022] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Progressive supranuclear palsy (PSP) is a 4R-tauopathy showing heterogeneous tau cytopathology commencing in the globus pallidus (GP) and the substantia nigra (SN), regions also associated with age-related iron accumulation. Abnormal iron levels have been extensively associated with tau pathology in neurodegenerative brains, however, its role in PSP pathogenesis remains yet unknown. We perform the first cell type-specific evaluation of PSP iron homeostasis and the closely related oxygen homeostasis, in relation to tau pathology in human postmortem PSP brains. METHODS In brain regions vulnerable to PSP pathology (GP, SN, and putamen), we visualized iron deposition in tau-affected and unaffected neurons, astroglia, oligodendrocytes, and microglia, using a combination of iron staining with immunolabelling. To further explore molecular pathways underlying our observations, we examined the expression of key iron and oxygen homeostasis mRNA transcripts and proteins. RESULTS We found astrocytes as the major cell type accumulating iron in the early affected regions of PSP, highly associated with cellular tau pathology. The same regions are affected by dysregulated expression of alpha and beta hemoglobin and neuroglobin showing contrasting patterns. We discovered changes in iron and oxygen homeostasis-related gene expression associated with aging of the brain, and identified dysregulated expression of rare neurodegeneration with brain iron accumulation (NBIA) genes associated with tau pathology to distinguish PSP from the healthy aging brain. INTERPRETATION We present novel aspects of PSP pathophysiology highlighting an overlap with NBIA pathways. Our findings reveal potential novel targets for therapy development and have implications beyond PSP for other iron-associated neurodegenerative diseases. ANN NEUROL 2023;93:431-445.
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Affiliation(s)
- Seojin Lee
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Ivan Martinez-Valbuena
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Carlos E de Andrea
- Department of Pathology, Clínica Universidad de Navarra, Pamplona, Spain.,Department of Anatomy, Physiology, and Pathology, University of Navarra, Pamplona, Spain.,Navarra Institute for Health Research (IdISNA), Pamplona, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | - Maria Villalba-Esparza
- Department of Pathology, Clínica Universidad de Navarra, Pamplona, Spain.,Department of Anatomy, Physiology, and Pathology, University of Navarra, Pamplona, Spain.,Navarra Institute for Health Research (IdISNA), Pamplona, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | - Suganthini Ilaalagan
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Blas Couto
- Edmond J. Safra Program in Parkinson's Disease, Rossy Program for PSP Research and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Naomi P Visanji
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada.,Edmond J. Safra Program in Parkinson's Disease, Rossy Program for PSP Research and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada
| | - Anthony E Lang
- Edmond J. Safra Program in Parkinson's Disease, Rossy Program for PSP Research and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Gabor G Kovacs
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada.,Edmond J. Safra Program in Parkinson's Disease, Rossy Program for PSP Research and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada.,Laboratory Medicine Program, University Health Network, Toronto, Ontario, Canada
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12
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Ainani H, Bouchmaa N, Ben Mrid R, El Fatimy R. Liquid-liquid phase separation of protein tau: An emerging process in Alzheimer's disease pathogenesis. Neurobiol Dis 2023; 178:106011. [PMID: 36702317 DOI: 10.1016/j.nbd.2023.106011] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 01/04/2023] [Accepted: 01/21/2023] [Indexed: 01/24/2023] Open
Abstract
Metabolic reactions within cells occur in various isolated compartments with or without borders, the latter being known as membrane-less organelles (MLOs). The MLOs show liquid-like properties and are formed by a process known as liquid-liquid phase separation (LLPS). MLOs contribute to different molecules interactions such as protein-protein, protein-RNA, and RNA-RNA driven by various factors, such as multivalency of intrinsic disorders. MLOs are involved in several cell signaling pathways such as transcription, immune response, and cellular organization. However, disruption of these processes has been found in different pathologies. Recently, it has been demonstrated that protein aggregates, a characteristic of some neurodegenerative diseases, undergo similar phase separation. Tau protein is known as a major neurofibrillary tangles component in Alzheimer's disease (AD). This protein can undergo phase separation to form a MLO known as tau droplet in vitro and in vivo, and this process can be facilitated by several factors, including crowding agents, RNA, and phosphorylation. Tau droplet has been shown to mature into insoluble aggregates suggesting that this process may precede and induce neurodegeneration in AD. Here we review major factors involved in liquid droplet formation within a cell. Additionally, we highlight recent findings concerning tau aggregation following phase separation in AD, along with the potential therapeutic strategies that could be explored in this process against the progression of this pathology.
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Affiliation(s)
- Hassan Ainani
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Najat Bouchmaa
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Reda Ben Mrid
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Rachid El Fatimy
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco.
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13
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Sieme D, Griesinger C, Rezaei-Ghaleh N. Metal Binding to Sodium Heparin Monitored by Quadrupolar NMR. Int J Mol Sci 2022; 23:ijms232113185. [PMID: 36361973 PMCID: PMC9655979 DOI: 10.3390/ijms232113185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/18/2022] [Accepted: 10/26/2022] [Indexed: 11/16/2022] Open
Abstract
Heparins and heparan sulfate polysaccharides are negatively charged glycosaminoglycans and play important roles in cell-to-matrix and cell-to-cell signaling processes. Metal ion binding to heparins alters the conformation of heparins and influences their function. Various experimental techniques have been used to investigate metal ion-heparin interactions, frequently with inconsistent results. Exploiting the quadrupolar 23Na nucleus, we herein develop a 23Na NMR-based competition assay and monitor the binding of divalent Ca2+ and Mg2+ and trivalent Al3+ metal ions to sodium heparin and the consequent release of sodium ions from heparin. The 23Na spin relaxation rates and translational diffusion coefficients are utilized to quantify the metal ion-induced release of sodium ions from heparin. In the case of the Al3+ ion, the complementary approach of 27Al quadrupolar NMR is employed as a direct probe of ion binding to heparin. Our NMR results demonstrate at least two metal ion-binding sites with different affinities on heparin, potentially undergoing dynamic exchange. For the site with lower metal ion binding affinity, the order of Ca2+ > Mg2+ > Al3+ is obtained, in which even the weakly binding Al3+ ion is capable of displacing sodium ions from heparin. Overall, the multinuclear quadrupolar NMR approach employed here can monitor and quantify metal ion binding to heparin and capture different modes of metal ion-heparin binding.
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Affiliation(s)
- Daniel Sieme
- Department of NMR-Based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, D-37077 Göttingen, Germany
| | - Christian Griesinger
- Department of NMR-Based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, D-37077 Göttingen, Germany
| | - Nasrollah Rezaei-Ghaleh
- Department of NMR-Based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, D-37077 Göttingen, Germany
- Institute of Physical Biology, Heinrich Heine University (HHU) Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
- Institute of Biological Information Processing, IBI-7: Structural Biochemistry, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, D-52428 Jülich, Germany
- Correspondence: or
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14
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Liquid-Liquid Phase Separation Promotes Protein Aggregation and Its Implications in Ferroptosis in Parkinson’s Disease Dementia. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:7165387. [PMID: 36246407 PMCID: PMC9560807 DOI: 10.1155/2022/7165387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/07/2022] [Accepted: 09/16/2022] [Indexed: 11/17/2022]
Abstract
The pathological features of PDD are represented by dopaminergic neuronal death and intracellular α-synuclein (α-syn) aggregation. The interaction of iron accumulation with α-syn and tau was further explored as an essential pathological mechanism of PDD. However, the links and mechanisms between these factors remain unclear. Studies have shown that the occurrence and development of neurodegenerative diseases such as PDD are closely related to the separation of abnormal phases. Substances such as proteins can form droplets through liquid-liquid phase separation (LLPS) under normal physiological conditions and even undergo further liquid-solid phase transitions to form solid aggregates under disease or regulatory disorders, leading to pathological phenomena. By analyzing the existing literature, we propose that LLPS is the crucial mechanism causing abnormal accumulation of α-syn, tau, and other proteins in PDD, and its interaction with iron metabolism disorder is the key factor driving ferroptosis in PDD. Therefore, we believe that LLPS can serve as one of the means to explain the pathological mechanism of PDD. Determining the significance of LLPS in neurodegenerative diseases such as PDD will stimulate interest in research into treatments based on interference with abnormal LLPS.
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15
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Han Y, Ye H, Li P, Zeng Y, Yang J, Gao M, Su Z, Huang Y. In vitro characterization and molecular dynamics simulation reveal mechanism of 14-3-3ζ regulated phase separation of the tau protein. Int J Biol Macromol 2022; 208:1072-1081. [PMID: 35381286 DOI: 10.1016/j.ijbiomac.2022.03.215] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/10/2022] [Accepted: 03/31/2022] [Indexed: 11/29/2022]
Abstract
As a major microtubule-associated protein, tau is involved in the assembly of microtubules in the central nervous system. However, under pathological conditions tau assembles into amyloid filaments. Liquid droplets formed by liquid-liquid phase separation (LLPS) are a recently identified assembly state of tau and may have a major effect on the physiological function of tau and the formation of tau aggregates. 14-3-3 proteins are ubiquitously expressed in various tissues and regulate a wide variety of biological processes. In this work, we demonstrate that 14-3-3ζ is recruited into tau droplets and regulates tau LLPS by in vitro assays. While the mobility of tau molecules inside the droplets is not affected in the presence of 14-3-3ζ, the amount and size of droplets can vary significantly. Mechanistic studies reveal that 14-3-3ζ regulates tau LLPS by electrostatic interactions and hydrophobic interactions with the proline-rich domain and the microtubule-binding domain of tau. Surprisingly, the disordered C-terminal tail rather than the amphipathic binding groove of 14-3-3ζ plays a key role. Our findings not only provide a novel dimension to understand the interactions between 14 and 3-3 proteins and tau, but also suggest that 14-3-3 proteins may play an important role in regulating the LLPS of their binding partners.
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Affiliation(s)
- Yue Han
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Haiqiong Ye
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Ping Li
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Yifan Zeng
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Jing Yang
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Meng Gao
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China.
| | - Zhengding Su
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Yongqi Huang
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan 430068, China; Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China; Department of Biological Engineering, Hubei University of Technology, Wuhan 430068, China.
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16
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Juan SMA, Daglas M, Adlard P. Tau pathology, metal dyshomeostasis and repetitive mild traumatic brain injury: an unexplored link paving the way for neurodegeneration. J Neurotrauma 2022; 39:902-922. [PMID: 35293225 DOI: 10.1089/neu.2021.0241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Repetitive mild traumatic brain injury (r-mTBI), commonly experienced by athletes and military personnel, causes changes in multiple intracellular pathways, one of which involves the tau protein. Tau phosphorylation plays a role in several neurodegenerative conditions including chronic traumatic encephalopathy (CTE), a progressive neurodegenerative disorder linked to repeated head trauma. There is now mounting evidence suggesting that tau phosphorylation may be regulated by metal ions (such as iron, zinc and copper), which themselves are implicated in ageing and neurodegenerative disorders such as Alzheimer's disease (AD). Recent work has also shown that a single TBI can result in age-dependent and region-specific modulation of metal ions. As such, this review explores the link between TBI, CTE, ageing and neurodegeneration with a specific focus on the involvement of (and interaction between) tau pathology and metal dyshomeostasis. The authors highlight that metal dyshomeostasis has yet to be investigated in the context of repeat head trauma or CTE. Given the evidence that metal dyshomeostasis contributes to the onset and/or progression of neurodegeneration, and that CTE itself is a neurodegenerative condition, this brings to light an uncharted link that should be explored. The development of adequate models of r-mTBI and/or CTE will be crucial in deepening our understanding of the pathological mechanisms that drive the clinical manifestations in these conditions and also in the development of effective therapeutics targeted towards slowing progressive neurodegenerative disorders.
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Affiliation(s)
- Sydney M A Juan
- The Florey Institute of Neuroscience and Mental Health, 56369, 30 Royal Parade, Parkville, Melbourne, Victoria, Australia, 3052;
| | - Maria Daglas
- The Florey Institute of Neuroscience and Mental Health, 56369, Parkville, Victoria, Australia;
| | - Paul Adlard
- Florey Institute of Neuroscience and Mental Health, 56369, Parkville, Victoria, Australia;
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Venkatramani A, Mukherjee S, Kumari A, Panda D. Shikonin impedes phase separation and aggregation of tau and protects SH-SY5Y cells from the toxic effects of tau oligomers. Int J Biol Macromol 2022; 204:19-33. [PMID: 35120943 DOI: 10.1016/j.ijbiomac.2022.01.172] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/20/2022] [Accepted: 01/28/2022] [Indexed: 12/22/2022]
Abstract
Tauopathies such as Alzheimer's and Parkinson's diseases involve the abnormal deposition of tau aggregates in the brain and neuronal tissues. We report that a natural naphthoquinone, shikonin, impeded the oligomerization and fibrillization of tau. The compound strongly inhibited heparin, arachidonic acid, and RNA-induced tau aggregation. Atomic force microscopy, dynamic light scattering, SDS-PAGE, and dot blot assays revealed that shikonin diminished tau oligomerization and decreased the mean size of tau oligomers. Transmission electron microscopy and atomic force microscopy analysis further showed that shikonin could suppress tau fibrillization and shorten the tau filaments. Shikonin inhibited tau droplet formation. The compound significantly reduced the aggregation rate of a tryptophan mutant (Y310W-tau) of tau. In addition, shikonin disaggregated preformed tau filaments with a half-maximal disaggregation concentration (DC50) of 6.3 ± 0.4 μM. Pre-treatment of neuroblastoma cells (SH-SY5Y) with shikonin protected the cells from the toxicity induced by tau oligomers and increased their viability. The findings imply that shikonin inhibited several steps in the tau aggregation pathways, especially the early stages, such as liquid-liquid phase separation. Therefore, shikonin is an attractive candidate for developing a therapy against tauopathy.
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Affiliation(s)
- Anuradha Venkatramani
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Sandipan Mukherjee
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Anuradha Kumari
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Dulal Panda
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India; National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, SAS. Nagar, Mohali 160062, Punjab, India.
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