1
|
Li Y, Peng X. Comparison of the force fields on monomeric and fibrillar PHF6 of tau protein. Biophys Chem 2021; 277:106631. [PMID: 34116358 DOI: 10.1016/j.bpc.2021.106631] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/18/2021] [Accepted: 06/01/2021] [Indexed: 11/19/2022]
Abstract
The hexapeptide 306VQIVYK311 (PHF6) plays an important role in the aggregation of Tau protein, which is a hallmark of the Alzheimer's disease (AD). In this article, we systematically compare the effects of eight popular all-atom force fields on the monomeric and fibrillar PHF6 in the molecular dynamics (MD) simulations, which could be helpful in the computer-aided drug design against PHF6. We show that the fibrillar PHF6 prefers β-strand-like structures in all the force fields while the monomer has different structural preferences depending on the force fields. The interactions for stabilizing the fibril are further investigated. In the end, according to the interactions revealed by NMR and the stability of the fibril in the literature, we benchmark the force fields.
Collapse
Affiliation(s)
- Yanchun Li
- Center for Quantum Technology Research, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Xubiao Peng
- Center for Quantum Technology Research, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China; Beijing Academy of Quantum Information Sciences, Beijing 100193, China.
| |
Collapse
|
2
|
Desale SE, Chidambaram H, Chinnathambi S. G-protein coupled receptor, PI3K and Rho signaling pathways regulate the cascades of Tau and amyloid-β in Alzheimer's disease. MOLECULAR BIOMEDICINE 2021; 2:17. [PMID: 35006431 PMCID: PMC8607389 DOI: 10.1186/s43556-021-00036-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/18/2021] [Indexed: 12/16/2022] Open
Abstract
Alzheimer's disease is a progressive neurodegenerative disease characterized by the presence of amyloid-β plaques in the extracellular environment and aggregates of Tau protein that forms neurofibrillary tangles (NFTs) in neuronal cells. Along with these pathological proteins, the disease shows neuroinflammation, neuronal death, impairment in the immune function of microglia and synaptic loss, which are mediated by several important signaling pathways. The PI3K/Akt-mediated survival-signaling pathway is activated by many receptors such as G-protein coupled receptors (GPCRs), triggering receptor expressed on myeloid cells 2 (TREM2), and lysophosphatidic acid (LPA) receptor. The signaling pathway not only increases the survival of neurons but also regulates inflammation, phagocytosis, cellular protection, Tau phosphorylation and Aβ secretion as well. In this review, we focused on receptors, which activate PI3K/Akt pathway and its potential to treat Alzheimer's disease. Among several membrane receptors, GPCRs are the major drug targets for therapy, and GPCR signaling pathways are altered during Alzheimer's disease. Several GPCRs are involved in the pathogenic progression, phosphorylation of Tau protein by activation of various cellular kinases and are involved in the amyloidogenic pathway of amyloid-β synthesis. Apart from various GPCR signaling pathways, GPCR regulating/ interacting proteins are involved in the pathogenesis of Alzheimer's disease. These include several small GTPases, Ras homolog enriched in brain, GPCR associated sorting proteins, β-arrestins, etc., that play a critical role in disease progression and has been elaborated in this review.
Collapse
Affiliation(s)
- Smita Eknath Desale
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411008 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002 India
| | - Hariharakrishnan Chidambaram
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411008 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002 India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411008 India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002 India
| |
Collapse
|
3
|
Jangampalli Adi P, Reddy PH. Phosphorylated tau targeted small-molecule PROTACs for the treatment of Alzheimer's disease and tauopathies. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166162. [PMID: 33940164 DOI: 10.1016/j.bbadis.2021.166162] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
Tau is a microtubule-stabilizing protein that plays an important role in the formation of axonal microtubules in neurons. Phosphorylated tau (p-Tau) has received great attention in the field of Alzheimer's disease (AD) as a potential therapeutic target due to its involvement with synaptic damage and neuronal dysfunction. Mounting evidence suggests that amyloid beta (Aβ)-targeted clinical trials continuously failed; therefore, it is important to consider alternative therapeutic strategies such as p-tau-PROTACs targeted small molecules for AD and other tauopathies. The present article describes the characteristics of tau biology, structure, and function in both healthy and pathological states in AD. It also explains data from studies that have identified the involvement of p-tau in neuronal damage and synaptic and cognitive functions in AD. Current article also covers several aspects, including small molecule inhibitors, and the development of p-tau-PROTACs targeted drug molecules to treat patients with AD and other tauopathies.
Collapse
Affiliation(s)
| | - P Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Public Health, Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Speech, Language, and Hearing Sciences, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| |
Collapse
|
4
|
Gu JL, Liu F. Tau in Alzheimer's Disease: Pathological Alterations and an Attractive Therapeutic Target. Curr Med Sci 2021; 40:1009-1021. [PMID: 33428128 DOI: 10.1007/s11596-020-2282-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 12/03/2020] [Indexed: 12/20/2022]
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disease with two major hallmarks: extracellular amyloid plaques made of amyloid-β (Aβ) and intracellular neurofibrillary tangles (NFTs) of abnormally hyperphosphorylated tau. The number of NFTs correlates positively with the severity of dementia in AD patients. However, there is still no efficient therapy available for AD treatment and prevention so far. A deeper understanding of AD pathogenesis has identified novel strategies for the generation of specific therapies over the past few decades. Several studies have suggested that the prion-like seeding and spreading of tau pathology in the brain may be a key driver of AD. Tau protein is considered as a promising candidate target for the development of therapeutic interventions due to its considerable pathological role in a variety of neurodegenerative disorders. Abnormal tau hyperphosphorylation plays a detrimental pathological role, eventually leading to neurodegeneration. In the present review, we describe the recent research progresses in the pathological mechanisms of tau protein in AD and briefly discuss tau-based therapeutic strategies.
Collapse
Affiliation(s)
- Jian-Lan Gu
- Department of Biochemistry and Molecular Biology, School of Medicine, Nantong University, Nantong, 226001, China. .,Co-innovation Center of Neuroregeneration, Key Laboratory of Neuroregeneration and Ministry of Education of Jiangsu, Nantong, 226001, China.
| | - Fei Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, 10314, USA
| |
Collapse
|
5
|
Chidambaram H, Chinnathambi S. Role of cysteines in accelerating Tau filament formation. J Biomol Struct Dyn 2020; 40:4366-4375. [PMID: 33317395 DOI: 10.1080/07391102.2020.1856720] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease is majorly associated with intracellular accumulation of Tau into paired helical filaments and tangles. The self-aggregated dimeric and oligomeric species of Tau formed are more toxic to neuronal cells and acts as seeds for filament formation. The two cysteine residues and the two hexapeptide regions of full-length Tau play a key role in initialization and filament formation during Tau aggregation. The role of cysteine residues in Tau aggregation has been studied by in-vitro aggregation assay that was measured by Thioflavin S fluorescence to observe the kinetics of aggregation. In this study, we have performed in-vitro aggregation assay with recombinant full-length Tau and the cysteine mutants to understand the mechanism of cysteine independent Tau aggregation. Here, we report that cysteine mutant full-length Tau can aggregate to form filaments under in-vitro conditions. To visualize the polymorphisms of Tau and cysteine mutants under different aggregation conditions anionic cofactor, heparin was employed. Wild-type Tau showed rapid aggregation to form oligomers and filaments. On the other hand, the cysteine mutant delayed the initial Tau aggregation. This indicates the importance of cysteine residues in accelerating initial Tau nucleation for its aggregation. The filament morphology of wild-type and cysteine mutant Tau has been characterized using transmission electron microscopy and high-resolution transmission electron microscopy.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Hariharakrishnan Chidambaram
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| |
Collapse
|
6
|
Soeda Y, Takashima A. New Insights Into Drug Discovery Targeting Tau Protein. Front Mol Neurosci 2020; 13:590896. [PMID: 33343298 PMCID: PMC7744460 DOI: 10.3389/fnmol.2020.590896] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 11/10/2020] [Indexed: 12/17/2022] Open
Abstract
Microtubule-associated protein tau is characterized by the fact that it is an intrinsically disordered protein due to its lack of a stable conformation and high flexibility. Intracellular inclusions of fibrillar forms of tau with a β-sheet structure accumulate in the brain of patients with Alzheimer's disease and other tauopathies. Accordingly, detachment of tau from microtubules and transition of tau from a disordered state to an abnormally aggregated state are essential events preceding the onset of tau-related diseases. Many reports have shown that this transition is caused by post-translational modifications, including hyperphosphorylation and acetylation. The misfolded tau is self-assembled and forms a tau oligomer before the appearance of tau inclusions. Animal and pathological studies using human samples have demonstrated that tau oligomer formation contributes to neuronal loss. During the progression of tauopathies, tau seeds are released from cells and incorporated into other cells, leading to the propagation of pathological tau aggregation. Accumulating evidence suggests several potential approaches for blocking tau-mediated toxicity: (1) direct inhibition of pathological tau aggregation and (2) inhibition of tau post-translational modifications that occur prior to pathological tau aggregation, (3) inhibition of tau propagation and (4) stabilization of microtubules. In addition to traditional low-molecular-weight compounds, newer drug discovery approaches such as the development of medium-molecular-weight drugs (peptide- or oligonucleotide-based drugs) and high-molecular-weight drugs (antibody-based drugs) provide alternative pathways to preventing the formation of abnormal tau. Of particular interest are recent studies suggesting that tau droplet formation by liquid-liquid phase separation may be the initial step in aberrant tau aggregation, as well results that implicate roles for tau in dendritic and nuclear functions. Here, we review the mechanisms through which drugs can target tau and consider recent clinical trials for the treatment of tauopathies. In addition, we discuss the utility of these newer strategies and propose future directions for research on tau-targeted therapeutics.
Collapse
Affiliation(s)
- Yoshiyuki Soeda
- Laboratory for Alzheimer's Disease, Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
| | - Akihiko Takashima
- Laboratory for Alzheimer's Disease, Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
| |
Collapse
|
7
|
Chidambaram H, Das R, Chinnathambi S. Interaction of Tau with the chemokine receptor, CX3CR1 and its effect on microglial activation, migration and proliferation. Cell Biosci 2020; 10:109. [PMID: 32944223 PMCID: PMC7493323 DOI: 10.1186/s13578-020-00474-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/08/2020] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease that leads to progressive loss of memory and dementia. The pathological hallmarks of AD include extracellular accumulation of amyloid-β peptides forming senile plaques and intracellular accumulation of Tau oligomers and filamentous species. Tau is a microtubule-binding protein that stabilizes tubulin to form microtubules under physiological condition. In AD/ pathological condition, Tau detaches from microtubules and aggregates to form oligomers of different sizes and filamentous species such as paired helical filaments. Microglia are the resident brain macrophages that are involved in the phagocytosis of microbes, cellular debris, misfolded and aggregated proteins. Chemokine receptor, CX3CR1 is mostly expressed on microglia and is involved in maintaining the microglia in a quiescent state by binding to its ligand, fractalkine (CX3CL1), which is expressed in neurons as both soluble or membrane-bound state. Hence, under physiological conditions, the CX3CR1/CX3CL1 axis plays a significant role in maintaining the central nervous system (CNS) homeostasis. Further, CX3CR1/CX3CL1 signalling is involved in the synthesis of anti-inflammatory cytokines and also has a significant role in cytoskeletal rearrangement, migration, apoptosis and proliferation. In AD brain, the expression level of fractalkine is reduced, and hence Tau competes to interact with its receptor, CX3CR1. In microglia, phagocytosis and internalization of extracellular Tau species occurs in the presence of a chemokine receptor, CX3CR1 which binds directly to Tau and promotes its internalization. In this review, the pathophysiological roles of CX3CR1/fractalkine signalling in microglia and neurons at different stages of Alzheimer's disease and the possible role of CX3CR1/Tau signalling has been widely discussed.
Collapse
Affiliation(s)
- Hariharakrishnan Chidambaram
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India
- Academy of Scientific and Innovative Research (AcSIR), 411008 Pune, India
| | - Rashmi Das
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India
- Academy of Scientific and Innovative Research (AcSIR), 411008 Pune, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India
- Academy of Scientific and Innovative Research (AcSIR), 411008 Pune, India
| |
Collapse
|
8
|
Muralidar S, Ambi SV, Sekaran S, Thirumalai D, Palaniappan B. Role of tau protein in Alzheimer's disease: The prime pathological player. Int J Biol Macromol 2020; 163:1599-1617. [PMID: 32784025 DOI: 10.1016/j.ijbiomac.2020.07.327] [Citation(s) in RCA: 93] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 07/07/2020] [Accepted: 07/31/2020] [Indexed: 01/11/2023]
Abstract
Alzheimer's disease (AD) is a prevalently found tauopathy characterized by memory loss and cognitive insufficiency. AD is an age-related neurodegenerative disease with two major hallmarks which includes extracellular amyloid plaques made of amyloid-β (Aβ) and intracellular neurofibrillary tangles of hyperphosphorylated tau. With population aging worldwide, there is an indispensable need for treatment strategies that can potentially manage this developing dementia. Despite broad researches on targeting Aβ in the past two decades, research findings on Aβ targeted therapeutics failed to prove efficacy in the treatment of AD. Tau protein with its extensive pathological role in several neurodegenerative diseases can be considered as a promising target candidate for developing therapeutic interventions. The abnormal hyperphosphorylation of tau plays detrimental pathological functions which ultimately lead to neurodegeneration. This review will divulge the importance of tau in AD pathogenesis, the interplay of Aβ and tau, the pathological functions of tau, and potential therapeutic strategies for an effective management of neuronal disorders.
Collapse
Affiliation(s)
- Shibi Muralidar
- School of Chemical and Biotechnology, SASTRA Deemed-to-be-University, Thanjavur 613401, Tamil Nadu, India
| | - Senthil Visaga Ambi
- School of Chemical and Biotechnology, SASTRA Deemed-to-be-University, Thanjavur 613401, Tamil Nadu, India.
| | - Saravanan Sekaran
- School of Chemical and Biotechnology, SASTRA Deemed-to-be-University, Thanjavur 613401, Tamil Nadu, India; Centre for Nanotechnology & Advanced Biomaterials (CeNTAB), School of Chemical and Biotechnology, SASTRA Deemed-to-be-University, Thanjavur 613401, Tamil Nadu, India
| | - Diraviyam Thirumalai
- School of Chemical and Biotechnology, SASTRA Deemed-to-be-University, Thanjavur 613401, Tamil Nadu, India
| | - Balamurugan Palaniappan
- School of Chemical and Biotechnology, SASTRA Deemed-to-be-University, Thanjavur 613401, Tamil Nadu, India
| |
Collapse
|
9
|
Gabr MT, Peccati F. Dual Targeting of Monomeric Tau and α-Synuclein Aggregation: A New Multitarget Therapeutic Strategy for Neurodegeneration. ACS Chem Neurosci 2020; 11:2051-2057. [PMID: 32579329 DOI: 10.1021/acschemneuro.0c00281] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Development of efficient multitargeted therapeutic strategies is crucial in facing the multifaceted nature of neurodegenerative diseases. Parkinson's disease (PD) and Alzheimer's disease (AD), the two most common neurodegenerative disorders, share a common hallmark of accumulation of misfolded protein aggregates which are Lewy bodies (LBs) and neurofibrillary tangles (NFTs), respectively. Tau protein and α-synuclein (α-syn), the precursors of LBs and NFTs, have demonstrated synergistic aggregation and neurotoxicity in both in vitro and in vivo models. Herein, we validate for the first time dual targeting of monomeric tau and α-syn aggregation as an efficient platform for development of multitarget therapeutics for neurological disorders. Cellular fluorescence resonance energy transfer (FRET)-based high-throughput screening for tau-binding compounds, followed by additional screening of the hits for their ability to impede α-syn aggregation identified MG-2119 as a potential lead. The high binding affinity of MG-2119 to monomeric tau was verified using cellular FRET assay, isothermal titration calorimetry (ITC), surface plasmon resonance (SPR), and microscale thermophoresis (MSH). Moreover, MG-2119 inhibited α-syn aggregation as revealed by thioflavin T (ThT) assay and dynamic light scattering (DLS) measurements. Interestingly, MG-2119 was capable of rescuing combined tau and α-syn-induced cytotoxicity in SH-SY5Y neuroblastoma cells in a dose-dependent manner. Less pronounced cell-rescuing effects were observed for single-targeted tau and α-syn aggregation inhibitors showcasing the superiority of the multitargeted approach described in this study. The satisfactory pharmacokinetic profile and low toxicity of MG-2119 hold promise for future optimization to develop potential therapeutics for neurological disorders.
Collapse
Affiliation(s)
- Moustafa T. Gabr
- Department of Radiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Francesca Peccati
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| |
Collapse
|