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von Maydell D, Wright S, Bonner JM, Staab C, Spitaleri A, Liu L, Pao PC, Yu CJ, Scannail AN, Li M, Boix CA, Mathys H, Leclerc G, Menchaca GS, Welch G, Graziosi A, Leary N, Samaan G, Kellis M, Tsai LH. Single-cell atlas of ABCA7 loss-of-function reveals impaired neuronal respiration via choline-dependent lipid imbalances. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.05.556135. [PMID: 38979214 PMCID: PMC11230156 DOI: 10.1101/2023.09.05.556135] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Loss-of-function (LoF) variants in the lipid transporter ABCA7 significantly increase the risk of Alzheimer's disease (odds ratio ∼2), yet the pathogenic mechanisms and the neural cell types affected by these variants remain largely unknown. Here, we performed single-nuclear RNA sequencing of 36 human post-mortem samples from the prefrontal cortex of 12 ABCA7 LoF carriers and 24 matched non-carrier control individuals. ABCA7 LoF was associated with gene expression changes in all major cell types. Excitatory neurons, which expressed the highest levels of ABCA7, showed transcriptional changes related to lipid metabolism, mitochondrial function, cell cycle-related pathways, and synaptic signaling. ABCA7 LoF-associated transcriptional changes in neurons were similarly perturbed in carriers of the common AD missense variant ABCA7 p.Ala1527Gly (n = 240 controls, 135 carriers), indicating that findings from our study may extend to large portions of the at-risk population. Consistent with ABCA7's function as a lipid exporter, lipidomic analysis of isogenic iPSC-derived neurons (iNs) revealed profound intracellular triglyceride accumulation in ABCA7 LoF, which was accompanied by a relative decrease in phosphatidylcholine abundance. Metabolomic and biochemical analyses of iNs further indicated that ABCA7 LoF was associated with disrupted mitochondrial bioenergetics that suggested impaired lipid breakdown by uncoupled respiration. Treatment of ABCA7 LoF iNs with CDP-choline (a rate-limiting precursor of phosphatidylcholine synthesis) reduced triglyceride accumulation and restored mitochondrial function, indicating that ABCA7 LoF-induced phosphatidylcholine dyshomeostasis may directly disrupt mitochondrial metabolism of lipids. Treatment with CDP-choline also rescued intracellular amyloid β -42 levels in ABCA7 LoF iNs, further suggesting a link between ABCA7 LoF metabolic disruptions in neurons and AD pathology. This study provides a detailed transcriptomic atlas of ABCA7 LoF in the human brain and mechanistically links ABCA7 LoF-induced lipid perturbations to neuronal energy dyshomeostasis. In line with a growing body of evidence, our study highlights the central role of lipid metabolism in the etiology of Alzheimer's disease.
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2
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Fu Z, Crooks EJ, Irizarry BA, Zhu X, Chowdhury S, Van Nostrand WE, Smith SO. An electrostatic cluster guides Aβ40 fibril formation in sporadic and Dutch-type cerebral amyloid angiopathy. J Struct Biol 2024; 216:108092. [PMID: 38615725 PMCID: PMC11162928 DOI: 10.1016/j.jsb.2024.108092] [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: 02/16/2024] [Revised: 04/08/2024] [Accepted: 04/11/2024] [Indexed: 04/16/2024]
Abstract
Cerebral amyloid angiopathy (CAA) is associated with the accumulation of fibrillar Aβ peptides upon and within the cerebral vasculature, which leads to loss of vascular integrity and contributes to disease progression in Alzheimer's disease (AD). We investigate the structure of human-derived Aβ40 fibrils obtained from patients diagnosed with sporadic or familial Dutch-type (E22Q) CAA. Using cryo-EM, two primary structures are identified containing elements that have not been observed in in vitro Aβ40 fibril structures. One population has an ordered N-terminal fold comprised of two β-strands stabilized by electrostatic interactions involving D1, E22, D23 and K28. This charged cluster is disrupted in the second population, which exhibits a disordered N-terminus and is favored in fibrils derived from the familial Dutch-type CAA patient. These results illustrate differences between human-derived CAA and AD fibrils, and how familial CAA mutations can guide fibril formation.
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Affiliation(s)
- Ziao Fu
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, United States; Laboratory of Molecular Neurobiology and Biophysics, The Rockefeller University, New York, NY 10065, United States
| | - Elliot J Crooks
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, United States
| | - Brandon A Irizarry
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, United States
| | - Xiaoyue Zhu
- George and Anne Ryan Institute for Neuroscience, Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI 02881, United States
| | - Saikat Chowdhury
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, United States; CSIR-Centre for Cellular & Molecular Biology, Habsiguda, Uppal Road, Hyderabad 500 007, Telangana, India; Academy of Scientific and Innovative Research (AcSIR), Kamala Nehru Nagar, Gaziabad 201 002, Uttar Pradesh, India
| | - William E Van Nostrand
- George and Anne Ryan Institute for Neuroscience, Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI 02881, United States.
| | - Steven O Smith
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, United States
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3
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Wolfram M, Tiwari MK, Hassenkam T, Li M, Bjerrum MJ, Meldal M. Cascade autohydrolysis of Alzheimer's Aβ peptides. Chem Sci 2023; 14:4986-4996. [PMID: 37206405 PMCID: PMC10189894 DOI: 10.1039/d2sc06668h] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 04/03/2023] [Indexed: 05/21/2023] Open
Abstract
Protein/peptide self-assembly into amyloid structures associates with major neurodegenerative disorders such as Alzheimer's disease (AD). Soluble assemblies (oligomers) of the Aβ peptide and their aggregates are perceived as neurotoxic species in AD. While screening for synthetic cleavage agents that could break down such aberrant assemblies through hydrolysis, we observed that the assemblies of Aβ oligopeptides, containing the nucleation sequence Aβ14-24 (H14QKLVFFAEDV24), could act as cleavage agents by themselves. Autohydrolysis showed a common fragment fingerprint among various mutated Aβ14-24 oligopeptides, Aβ12-25-Gly and Aβ1-28, and full-length Aβ1-40/42, under physiologically relevant conditions. Primary endoproteolytic autocleavage at the Gln15-Lys16, Lys16-Leu17 and Phe19-Phe20 positions was followed by subsequent exopeptidase self-processing of the fragments. Control experiments with homologous d-amino acid enantiomers Aβ12-25-Gly and Aβ16-25-Gly showed the same autocleavage pattern under similar reaction conditions. The autohydrolytic cascade reaction (ACR) was resilient to a broad range of conditions (20-37 °C, 10-150 μM peptide concentration at pH 7.0-7.8). Evidently, assemblies of the primary autocleavage fragments acted as structural/compositional templates (autocatalysts) for self-propagating autohydrolytic processing at the Aβ16-21 nucleation site, showing the potential for cross-catalytic seeding of the ACR in larger Aβ isoforms (Aβ1-28 and Aβ1-40/42). This result may shed new light on Aβ behaviour in solution and might be useful in the development of intervention strategies to decompose or inhibit neurotoxic Aβ assemblies in AD.
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Affiliation(s)
- Martin Wolfram
- Department of Chemistry, University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark +45 27202355 +45 21308299
| | - Manish K Tiwari
- Department of Chemistry, University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark +45 27202355 +45 21308299
| | - Tue Hassenkam
- Globe Institute, Section for Geobiology, Copenhagen University Øster Voldgade 5-7 1350 Copenhagen K Denmark
| | - Ming Li
- Technical University of Denmark, The Danish Hydrocarbon Research and Technology Centre Elektrovej, 2800 Kongens Lyngby Denmark
| | - Morten J Bjerrum
- Department of Chemistry, University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark +45 27202355 +45 21308299
| | - Morten Meldal
- Department of Chemistry, University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark +45 27202355 +45 21308299
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Li X, Zhou Y, Lu Z, Shan R, Sun D, Li J, Li P. Switchable enzyme mimics based on self-assembled peptides for polyethylene terephthalate degradation. J Colloid Interface Sci 2023; 646:198-208. [PMID: 37196493 DOI: 10.1016/j.jcis.2023.05.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 04/03/2023] [Accepted: 05/04/2023] [Indexed: 05/19/2023]
Abstract
Polyethylene terephthalate (PET), the most abundant polyester plastic, has become a global concern due to its refractoriness and accumulation in the environment. In this study, inspired by the structure and catalytic mechanism of the native enzyme, peptides, based on supramolecular self-assembly, were developed to construct enzyme mimics for PET degradation, which were achieved by combining the enzymatic active sites of serine, histidine and aspartate with the self-assembling polypeptide MAX. The two designed peptides with differences in hydrophobic residues at two positions exhibited a conformational transition from random coil to β-sheet by changing the pH and temperature, and the catalytic activity followed the self-assembly "switch" with the fibrils formed β-sheet, which could catalyze PET efficiently. Although the two peptides possessed same catalytic site, they showed different catalytic activities. Analysis of the structure - activity relationship of the enzyme mimics suggested that the high catalytic activity of the enzyme mimics for PET could be attributed to the formation of stable fibers of peptides and ordered arrangement of molecular conformation; in addition, hydrogen bonding and hydrophobic interactions, as the major forces, promoted effects of enzyme mimics on PET degradation. Enzyme mimics with PET-hydrolytic activity are a promising material for degrading PET and reducing environmental pollution.
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Affiliation(s)
- Xia Li
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China; School of Bioengineering, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China
| | - Yaoling Zhou
- School of Bioengineering, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China
| | - Zirui Lu
- School of Bioengineering, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China
| | - Ruida Shan
- School of Bioengineering, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China
| | - Dengyue Sun
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China; School of Bioengineering, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China
| | - Jianpeng Li
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China; School of Food Science and Engineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China.
| | - Piwu Li
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China; School of Bioengineering, Qilu University of Technology, Shandong Academy of Science, Jinan 250353, PR China.
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5
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Seira Curto J, Fernandez MR, Cladera J, Benseny-Cases N, Sanchez de Groot N. Aβ40 Aggregation under Changeable Conditions. Int J Mol Sci 2023; 24:ijms24098408. [PMID: 37176115 PMCID: PMC10179685 DOI: 10.3390/ijms24098408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/28/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023] Open
Abstract
Homeostasis is crucial for cell function, and disturbances in homeostasis can lead to health disorders. Under normal conditions, intracellular pH is maintained between 7.35 and 7.45. Altered endosomal and lysosomal pH together with a general drop in brain pH are associated with the aggregation of amyloid-β-peptide (Aβ) and the development of Alzheimer's disease. Under acidic conditions, close to the Aβ isoelectric point, the absence of charges favors the formation of intermolecular contacts and promotes aggregation. Here, we analyzed how pH levels affect the aggregation of Aβ40 considering the variations in brain pH and the coexistence of different aggregated conformations. Our results suggest that different macromolecular conformations can interact with each other and influence the aggregation process. In addition, we showed that neutral pH and physiological salt concentrations favor a slow aggregation, resulting in ordered, stable fibrils, with low cytotoxic effects. Overall, we highlight the complexity of the aggregation processes occurring in different physiological and pathological environments.
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Affiliation(s)
- Jofre Seira Curto
- Unitat de Bioquímica, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Maria Rosario Fernandez
- Unitat de Bioquímica, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Josep Cladera
- Unitat de Biofísica, Departament de Bioquímica i Biologia Molecular, Centre d'Estudis en Biofísica, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Núria Benseny-Cases
- Unitat de Biofísica, Departament de Bioquímica i Biologia Molecular, Centre d'Estudis en Biofísica, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Natalia Sanchez de Groot
- Unitat de Bioquímica, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
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6
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Zimbone S, Giuffrida ML, Sabatino G, Di Natale G, Tosto R, Consoli GML, Milardi D, Pappalardo G, Sciacca MFM. Aβ 8-20 Fragment as an Anti-Fibrillogenic and Neuroprotective Agent: Advancing toward Efficient Alzheimer's Disease Treatment. ACS Chem Neurosci 2023; 14:1126-1136. [PMID: 36857606 PMCID: PMC10020970 DOI: 10.1021/acschemneuro.2c00720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia, characterized by a spectrum of symptoms associated with memory loss and cognitive decline with deleterious consequences in everyday life. The lack of specific drugs for the treatment and/or prevention of this pathology makes AD an ever-increasing economic and social emergency. Oligomeric species of amyloid-beta (Aβ) are recognized as the primary cause responsible for synaptic dysfunction and neuronal degeneration, playing a crucial role in the onset of the pathology. Several studies have been focusing on the use of small molecules and peptides targeting oligomeric species to prevent Aβ aggregation and toxicity. Among them, peptide fragments derived from the primary sequence of Aβ have also been used to exploit any eventual recognition abilities toward the full-length Aβ parent peptide. Here, we test the Aβ8-20 fragment which contains the self-recognizing Lys-Leu-Val-Phe-Phe sequence and lacks Arg 5 and Asp 7 and the main part of the C-terminus, key points involved in the aggregation pathway and stabilization of the fibrillary structure of Aβ. In particular, by combining chemical and biological techniques, we show that Aβ8-20 does not undergo random coil to β sheet conformational transition, does not form amyloid fibrils by itself, and is not toxic for neuronal cells. Moreover, we demonstrate that Aβ8-20 mainly interacts with the 4-11 region of Aβ1-42 and inhibits the formation of toxic oligomeric species and Aβ fibrils. Finally, our data show that Aβ8-20 protects neuron-like cells from Aβ1-42 oligomer toxicity. We propose Aβ8-20 as a promising drug candidate for the treatment of AD.
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Affiliation(s)
- Stefania Zimbone
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Maria Laura Giuffrida
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Giuseppina Sabatino
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Giuseppe Di Natale
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Rita Tosto
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Grazia M L Consoli
- Consiglio Nazionale delle Ricerche, Istituto di Chimica Biomolecolare, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Danilo Milardi
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Giuseppe Pappalardo
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Michele F M Sciacca
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
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7
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Diaz-Espinoza R. Catalytically Active Amyloids as Future Bionanomaterials. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3802. [PMID: 36364578 PMCID: PMC9656882 DOI: 10.3390/nano12213802] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 10/14/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Peptides and proteins can aggregate into highly ordered and structured conformations called amyloids. These supramolecular structures generally have convergent features, such as the formation of intermolecular beta sheets, that lead to fibrillary architectures. The resulting fibrils have unique mechanical properties that can be exploited to develop novel nanomaterials. In recent years, sequences of small peptides have been rationally designed to self-assemble into amyloids that catalyze several chemical reactions. These amyloids exhibit reactive surfaces that can mimic the active sites of enzymes. In this review, I provide a state-of-the-art summary of the development of catalytically active amyloids. I will focus especially on catalytic activities mediated by hydrolysis, which are the most studied examples to date, as well as novel types of recently reported activities that promise to expand the possible repertoires. The combination of mechanical properties with catalytic activity in an amyloid scaffold has great potential for the development of future bionanomaterials aimed at specific applications.
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Affiliation(s)
- Rodrigo Diaz-Espinoza
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago 3363, Chile
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Ou W, Ohno Y, Yang J, Chandrashekar DV, Abdullah T, Sun J, Murphy R, Roules C, Jagadeesan N, Cribbs DH, Sumbria RK. Efficacy and Safety of a Brain-Penetrant Biologic TNF-α Inhibitor in Aged APP/PS1 Mice. Pharmaceutics 2022; 14:2200. [PMID: 36297637 PMCID: PMC9612380 DOI: 10.3390/pharmaceutics14102200] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/04/2022] [Accepted: 10/10/2022] [Indexed: 11/17/2022] Open
Abstract
Tumor necrosis factor alpha (TNF-α) plays a vital role in Alzheimer's disease (AD) pathology, and TNF-α inhibitors (TNFIs) modulate AD pathology. We fused the TNF-α receptor (TNFR), a biologic TNFI that sequesters TNF-α, to a transferrin receptor antibody (TfRMAb) to deliver the TNFI into the brain across the blood-brain barrier (BBB). TfRMAb-TNFR was protective in 6-month-old transgenic APP/PS1 mice in our previous work. However, the effects and safety following delayed chronic TfRMAb-TNFR treatment are unknown. Herein, we initiated the treatment when the male APP/PS1 mice were 10.7 months old (delayed treatment). Mice were injected intraperitoneally with saline, TfRMAb-TNFR, etanercept (non-BBB-penetrating TNFI), or TfRMAb for ten weeks. Biologic TNFIs did not alter hematology indices or tissue iron homeostasis; however, TfRMAb altered hematology indices, increased splenic iron transporter expression, and increased spleen and liver iron. TfRMAb-TNFR and etanercept reduced brain insoluble-amyloid beta (Aβ) 1-42, soluble-oligomeric Aβ, and microgliosis; however, only TfRMAb-TNFR reduced Aβ peptides, Thioflavin-S-positive Aβ plaques, and insoluble-oligomeric Aβ and increased plaque-associated phagocytic microglia. Accordingly, TfRMAb-TNFR improved spatial reference memory and increased BBB-tight junction protein expression, whereas etanercept did not. Overall, despite delayed treatment, TfRMAb-TNFR resulted in a better therapeutic response than etanercept without any TfRMAb-related hematology- or iron-dysregulation in aged APP/PS1 mice.
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Affiliation(s)
- Weijun Ou
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - Yuu Ohno
- Henry E. Riggs School of Applied Life Sciences, Keck Graduate Institute, 535 Watson Dr, Claremont, CA 91711, USA
| | - Joshua Yang
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
- Henry E. Riggs School of Applied Life Sciences, Keck Graduate Institute, 535 Watson Dr, Claremont, CA 91711, USA
| | - Devaraj V. Chandrashekar
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - Tamara Abdullah
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - Jiahong Sun
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - Riley Murphy
- Crean College of Health and Behavioral Sciences, Chapman University, Irvine, CA 92618, USA
| | - Chuli Roules
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - Nataraj Jagadeesan
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - David H. Cribbs
- MIND Institute, University of California, Irvine, CA 92697, USA
| | - Rachita K. Sumbria
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA
- Department of Neurology, University of California, Irvine, CA 92868, USA
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Immobilization Systems of Antimicrobial Peptide Ib−M1 in Polymeric Nanoparticles Based on Alginate and Chitosan. Polymers (Basel) 2022; 14:polym14153149. [PMID: 35956663 PMCID: PMC9370884 DOI: 10.3390/polym14153149] [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: 06/24/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 12/04/2022] Open
Abstract
The development of new strategies to reduce the use of traditional antibiotics has been a topic of global interest due to the resistance generated by multiresistant microorganisms, including Escherichia coli, as etiological agents of various diseases. Antimicrobial peptides are presented as an alternative for the treatment of infectious diseases caused by this type of microorganism. The Ib−M1 peptide meets the requirements to be used as an antimicrobial compound. However, it is necessary to use strategies that generate protection and resist the conditions encountered in a biological system. Therefore, in this study, we synthesized alginate and chitosan nanoparticles (Alg−Chi NPs) using the ionic gelation technique, which allows for the crosslinking of polymeric chains arranged in nanostructures by intermolecular interactions that can be either covalent or non-covalent. Such interactions can be achieved through the use of crosslinking agents that facilitate this binding. This technique allows for immobilization of the Ib−M1 peptide to form an Ib−M1/Alg−Chi bioconjugate. SEM, DLS, and FT-IR were used to determine the structural features of the nanoparticles. We evaluated the biological activity against E. coli ATCC 25922 and Vero mammalian cells, as well as the stability at various temperatures, pH, and proteases, of Ib−M1 and Ib−M1/Alg-Chi. The results showed agglomerates of nanoparticles with average sizes of 150 nm; an MIC of 12.5 µM, which was maintained in the bioconjugate; and cytotoxicity values close to 40%. Stability was maintained against pH and temperature; in proteases, it was only evidenced against pepsin in Ib−M1/Alg-Chi. The results are promising with respect to the use of Ib−M1 and Ib−M1/Alg−Chi as possible antimicrobial agents.
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Kalra AP, Eakins BB, Vagin SI, Wang H, Patel SD, Winter P, Aminpour M, Lewis JD, Rezania V, Shankar K, Scholes GD, Tuszynski JA, Rieger B, Meldrum A. A Nanometric Probe of the Local Proton Concentration in Microtubule-Based Biophysical Systems. NANO LETTERS 2022; 22:517-523. [PMID: 34962401 DOI: 10.1021/acs.nanolett.1c04487] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We show a double-functional fluorescence sensing paradigm that can retrieve nanometric pH information on biological structures. We use this method to measure the extent of protonic condensation around microtubules, which are protein polymers that play many roles crucial to cell function. While microtubules are believed to have a profound impact on the local cytoplasmic pH, this has been hard to show experimentally due to the limitations of conventional sensing techniques. We show that subtle changes in the local electrochemical surroundings cause a double-functional sensor to transform its spectrum, thus allowing a direct measurement of the protonic concentration at the microtubule surface. Microtubules concentrate protons by as much as one unit on the pH scale, indicating a charge storage role within the cell via the localized ionic condensation. These results confirm the bioelectrical significance of microtubules and reveal a sensing concept that can deliver localized biochemical information on intracellular structures.
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Affiliation(s)
- Aarat P Kalra
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States of America
| | - Boden B Eakins
- Department of Electrical and Computer Engineering, University of Alberta, 9107-116 St, Edmonton, Alberta T6G 2 V4, Canada
| | - Sergei I Vagin
- Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85747 Garching bei München, Germany
| | - Hui Wang
- Department of Physics, University of Alberta, 11335 Saskatchewan Dr NW, Edmonton, Alberta T6G 2E1, Canada
| | - Sahil D Patel
- Electrical and Computer Engineering Department, University of California, Santa Barbara, California 93106, United States of America
| | - Philip Winter
- Department of Oncology, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
| | - Maral Aminpour
- Department of Electrical and Computer Engineering, University of Alberta, 9107-116 St, Edmonton, Alberta T6G 2 V4, Canada
- Department of Oncology, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
| | - John D Lewis
- Department of Oncology, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
| | - Vahid Rezania
- Department of Physical Sciences, MacEwan University, Edmonton, Alberta T5J 4S2, Canada
| | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, 9107-116 St, Edmonton, Alberta T6G 2 V4, Canada
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States of America
| | - Jack A Tuszynski
- Department of Physics, University of Alberta, 11335 Saskatchewan Dr NW, Edmonton, Alberta T6G 2E1, Canada
- Department of Oncology, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
- Department of Mechanical and Aerospace Engineering (DIMEAS), Politecnico di Torino, Torino 10129, Italy
| | - Bernhard Rieger
- Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85747 Garching bei München, Germany
| | - Alkiviathes Meldrum
- Department of Physics, University of Alberta, 11335 Saskatchewan Dr NW, Edmonton, Alberta T6G 2E1, Canada
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11
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Loh D, Reiter RJ. Melatonin: Regulation of Biomolecular Condensates in Neurodegenerative Disorders. Antioxidants (Basel) 2021; 10:1483. [PMID: 34573116 PMCID: PMC8465482 DOI: 10.3390/antiox10091483] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 12/12/2022] Open
Abstract
Biomolecular condensates are membraneless organelles (MLOs) that form dynamic, chemically distinct subcellular compartments organizing macromolecules such as proteins, RNA, and DNA in unicellular prokaryotic bacteria and complex eukaryotic cells. Separated from surrounding environments, MLOs in the nucleoplasm, cytoplasm, and mitochondria assemble by liquid-liquid phase separation (LLPS) into transient, non-static, liquid-like droplets that regulate essential molecular functions. LLPS is primarily controlled by post-translational modifications (PTMs) that fine-tune the balance between attractive and repulsive charge states and/or binding motifs of proteins. Aberrant phase separation due to dysregulated membrane lipid rafts and/or PTMs, as well as the absence of adequate hydrotropic small molecules such as ATP, or the presence of specific RNA proteins can cause pathological protein aggregation in neurodegenerative disorders. Melatonin may exert a dominant influence over phase separation in biomolecular condensates by optimizing membrane and MLO interdependent reactions through stabilizing lipid raft domains, reducing line tension, and maintaining negative membrane curvature and fluidity. As a potent antioxidant, melatonin protects cardiolipin and other membrane lipids from peroxidation cascades, supporting protein trafficking, signaling, ion channel activities, and ATPase functionality during condensate coacervation or dissolution. Melatonin may even control condensate LLPS through PTM and balance mRNA- and RNA-binding protein composition by regulating N6-methyladenosine (m6A) modifications. There is currently a lack of pharmaceuticals targeting neurodegenerative disorders via the regulation of phase separation. The potential of melatonin in the modulation of biomolecular condensate in the attenuation of aberrant condensate aggregation in neurodegenerative disorders is discussed in this review.
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Affiliation(s)
- Doris Loh
- Independent Researcher, Marble Falls, TX 78654, USA
| | - Russel J. Reiter
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX 78229, USA
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12
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Duran-Meza E, Diaz-Espinoza R. Catalytic Amyloids as Novel Synthetic Hydrolases. Int J Mol Sci 2021; 22:ijms22179166. [PMID: 34502074 PMCID: PMC8431744 DOI: 10.3390/ijms22179166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/15/2021] [Accepted: 08/18/2021] [Indexed: 11/23/2022] Open
Abstract
Amyloids are supramolecular assemblies composed of polypeptides stabilized by an intermolecular beta-sheet core. These misfolded conformations have been traditionally associated with pathological conditions such as Alzheimer’s and Parkinson´s diseases. However, this classical paradigm has changed in the last decade since the discovery that the amyloid state represents a universal alternative fold accessible to virtually any polypeptide chain. Moreover, recent findings have demonstrated that the amyloid fold can serve as catalytic scaffolds, creating new opportunities for the design of novel active bionanomaterials. Here, we review the latest advances in this area, with particular emphasis on the design and development of catalytic amyloids that exhibit hydrolytic activities. To date, three different types of activities have been demonstrated: esterase, phosphoesterase and di-phosphohydrolase. These artificial hydrolases emerge upon the self-assembly of small peptides into amyloids, giving rise to catalytically active surfaces. The highly stable nature of the amyloid fold can provide an attractive alternative for the design of future synthetic hydrolases with diverse applications in the industry, such as the in situ decontamination of xenobiotics.
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Affiliation(s)
- Eva Duran-Meza
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile;
| | - Rodrigo Diaz-Espinoza
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago 9170022, Chile
- Correspondence:
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13
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Liu K, Li J, Raghunathan R, Zhao H, Li X, Wong STC. The Progress of Label-Free Optical Imaging in Alzheimer's Disease Screening and Diagnosis. Front Aging Neurosci 2021; 13:699024. [PMID: 34366828 PMCID: PMC8341907 DOI: 10.3389/fnagi.2021.699024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/02/2021] [Indexed: 01/13/2023] Open
Abstract
As the major neurodegenerative disease of dementia, Alzheimer's disease (AD) has caused an enormous social and economic burden on society. Currently, AD has neither clear pathogenesis nor effective treatments. Positron emission tomography (PET) and magnetic resonance imaging (MRI) have been verified as potential tools for diagnosing and monitoring Alzheimer's disease. However, the high costs, low spatial resolution, and long acquisition time limit their broad clinical utilization. The gold standard of AD diagnosis routinely used in research is imaging AD biomarkers with dyes or other reagents, which are unsuitable for in vivo studies owing to their potential toxicity and prolonged and costly process of the U.S. Food and Drug Administration (FDA) approval for human use. Furthermore, these exogenous reagents might bring unwarranted interference to mechanistic studies, causing unreliable results. Several label-free optical imaging techniques, such as infrared spectroscopic imaging (IRSI), Raman spectroscopic imaging (RSI), optical coherence tomography (OCT), autofluorescence imaging (AFI), optical harmonic generation imaging (OHGI), etc., have been developed to circumvent this issue and made it possible to offer an accurate and detailed analysis of AD biomarkers. In this review, we present the emerging label-free optical imaging techniques and their applications in AD, along with their potential and challenges in AD diagnosis.
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Affiliation(s)
- Kai Liu
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- Department of Gastrointestinal Surgery, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Jiasong Li
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
| | - Raksha Raghunathan
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
| | - Hong Zhao
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
| | - Xuping Li
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
| | - Stephen T. C. Wong
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
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14
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Michno W, Blennow K, Zetterberg H, Brinkmalm G. Refining the amyloid β peptide and oligomer fingerprint ambiguities in Alzheimer's disease: Mass spectrometric molecular characterization in brain, cerebrospinal fluid, blood, and plasma. J Neurochem 2021; 159:234-257. [PMID: 34245565 DOI: 10.1111/jnc.15466] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 06/11/2021] [Accepted: 07/06/2021] [Indexed: 01/05/2023]
Abstract
Since its discovery, amyloid-β (Aβ) has been the principal target of investigation of in Alzheimer's disease (AD). Over the years however, no clear correlation was found between the Aβ plaque burden and location, and AD-associated neurodegeneration and cognitive decline. Instead, diagnostic potential of specific Aβ peptides and/or their ratio, was established. For instance, a selective reduction in the concentration of the aggregation-prone 42 amino acid-long Aβ peptide (Aβ42) in cerebrospinal fluid (CSF) was put forward as reflective of Aβ peptide aggregation in the brain. With time, Aβ oligomers-the proposed toxic Aβ intermediates-have emerged as potential drivers of synaptic dysfunction and neurodegeneration in the disease process. Oligomers are commonly agreed upon to come in different shapes and sizes, and are very poorly characterized when it comes to their composition and their "toxic" properties. The concept of structural polymorphism-a diversity in conformational organization of amyloid aggregates-that depends on the Aβ peptide backbone, makes the characterization of Aβ aggregates and their role in AD progression challenging. In this review, we revisit the history of Aβ discovery and initial characterization and highlight the crucial role mass spectrometry (MS) has played in this process. We critically review the common knowledge gaps in the molecular identity of the Aβ peptide, and how MS is aiding the characterization of higher order Aβ assemblies. Finally, we go on to present recent advances in MS approaches for characterization of Aβ as single peptides and oligomers, and convey our optimism, as to how MS holds a promise for paving the way for progress toward a more comprehensive understanding of Aβ in AD research.
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Affiliation(s)
- Wojciech Michno
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.,Department of Pediatrics, Stanford University School of Medicine, Stanford University, Stanford, CA, USA
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Gunnar Brinkmalm
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
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15
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Magami K, Hachiya N, Morikawa K, Fujii N, Takata T. Isomerization of Asp is essential for assembly of amyloid-like fibrils of αA-crystallin-derived peptide. PLoS One 2021; 16:e0250277. [PMID: 33857260 PMCID: PMC8049310 DOI: 10.1371/journal.pone.0250277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 04/01/2021] [Indexed: 11/22/2022] Open
Abstract
Post-translational modifications are often detected in age-related diseases associated with protein misfolding such as cataracts from aged lenses. One of the major post-translational modifications is the isomerization of aspartate residues (L-isoAsp), which could be non-enzymatically and spontaneously occurring in proteins, resulting in various effects on the structure and function of proteins including short peptides. We have reported that the structure and function of an αA66–80 peptide, corresponding to the 66–80 (66SDRDKFVIFLDVKHF80) fragment of human lens αA-crystallin, was dramatically altered by the isomerization of aspartate residue (Asp) at position 76. In the current study, we observed amyloid-like fibrils of L-isoAsp containing αA66–80 using electron microscopy. The contribution of each amino acid for the peptide structure was further evaluated by circular dichroism (CD), bis-ANS, and thioflavin T fluorescence using 14 alanine substituents of αA66–80, including L-isoAsp at position 76. CD of 14 alanine substituents demonstrated random coiled structures except for the substituents of positively charged residues. Bis-ANS fluorescence of peptide with substitution of hydrophobic residue with alanine revealed decreased hydrophobicity of the peptide. Thioflavin T fluorescence also showed that the hydrophobicity around Asp76 of the peptide is important for the formation of amyloid-like fibrils. One of the substitutes, H79A (SDRDKFVIFL(L-isoD)VKAF) demonstrated an exact β-sheet structure in CD and highly increased Thioflavin T fluorescence. This phenomenon was inhibited by the addition of protein-L-isoaspartate O-methyltransferase (PIMT), which is an enzyme that changes L-isoAsp into Asp. These interactions were observed even after the formation of amyloid-like fibrils. Thus, isomerization of Asp in peptide is key to form fibrils of αA-crystallin-derived peptide, and L-isoAsp on fibrils can be a candidate for disassembling amyloid-like fibrils of αA-crystallin-derived peptides.
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Affiliation(s)
- Kosuke Magami
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Naomi Hachiya
- Tokyo Metropolitan Industrial Technology Research Institute, Aomi, Koto-ku, Tokyo, Japan
| | - Kazuo Morikawa
- Tokyo Metropolitan Industrial Technology Research Institute, Aomi, Koto-ku, Tokyo, Japan
| | - Noriko Fujii
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Sennan-gun, Osaka, Japan
| | - Takumi Takata
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Sennan-gun, Osaka, Japan
- * E-mail:
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16
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Cotrina EY, Gimeno A, Llop J, Jiménez-Barbero J, Quintana J, Prohens R, Cardoso I, Arsequell G. An Assay for Screening Potential Drug Candidates for Alzheimer's Disease That Act as Chaperones of the Transthyretin and Amyloid-β Peptides Interaction. Chemistry 2020; 26:17462-17469. [PMID: 32761825 DOI: 10.1002/chem.202002933] [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] [Received: 06/18/2020] [Revised: 08/03/2020] [Indexed: 11/08/2022]
Abstract
The protein transthyretin (TTR) modulates amyloid-β (Aβ) peptides deposition and processing and this physiological effect is further enhanced by treatment with iododiflunisal (IDIF), a small-molecule compound (SMC) with TTR tetramer stabilization properties, which behaves as chaperone of the complex. This knowledge has prompted us to design and optimize a rapid and simple high-throughput assay that relies on the ability of test compounds to form ternary soluble complexes TTR/Aβ/SMC that prevent Aβ aggregation. The method uses the shorter Aβ(12-28) sequence which is cheaper and simpler to use while retaining the aggregation properties of their parents Aβ(1-40) and Aβ(1-42). The test is carried out in 96-plate wells that are UV monitored for turbidity during 6 h. Given its reproducibility, we propose that this test can be a powerful tool for efficient screening of SMCs that act as chaperones of the TTR/Aβ interaction that may led to potential AD therapies.
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Affiliation(s)
- Ellen Y Cotrina
- Institut de Química Avançada de Catalunya (I.Q.A.C.-C.S.I.C.), Jordi Girona 18-26, 08034, Barcelona, Spain
| | - Ana Gimeno
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160, Derio, Spain.,Ikerbasque-Basque Foundation for Science, Maria Diaz de Haro 13, 48009, Bilbao, Spain.,Department of Organic Chemistry II, Faculty of Science & Technology, University of the Basque Country, 48940, Leioa, Bizkaia, Spain
| | - Jordi Llop
- CIC biomaGUNE, Basque Research and Technology Alliance (BRTA), 20014, San Sebastian, Spain
| | - Jesús Jiménez-Barbero
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160, Derio, Spain.,Ikerbasque-Basque Foundation for Science, Maria Diaz de Haro 13, 48009, Bilbao, Spain.,Department of Organic Chemistry II, Faculty of Science & Technology, University of the Basque Country, 48940, Leioa, Bizkaia, Spain
| | - Jordi Quintana
- Research Programme on Biomedical Informatics, Universitat Pompeu Fabra (UPF-IMIM), 08003, Barcelona, Spain
| | - Rafel Prohens
- Unitat de Polimorfisme i Calorimetria, Centres Científics i Tecnologics, Universitat de Barcelona, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Isabel Cardoso
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Gemma Arsequell
- Institut de Química Avançada de Catalunya (I.Q.A.C.-C.S.I.C.), Jordi Girona 18-26, 08034, Barcelona, Spain
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17
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Aziz AA, Siddiqui RA, Amtul Z. Engineering of fluorescent or photoactive Trojan probes for detection and eradication of β-Amyloids. Drug Deliv 2020; 27:917-926. [PMID: 32597244 PMCID: PMC8216438 DOI: 10.1080/10717544.2020.1785048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/14/2020] [Accepted: 06/16/2020] [Indexed: 11/04/2022] Open
Abstract
Trojan horse technology institutes a potentially promising strategy to bring together a diagnostic or cell-based drug design and a delivery platform. It provides the opportunity to re-engineer a novel multimodal, neurovascular detection probe, or medicine to fuse with blood-brain barrier (BBB) molecular Trojan horse. In Alzheimer's disease (AD) this could allow the targeted delivery of detection or therapeutic probes across the BBB to the sites of plaques and tangles development to image or decrease amyloid load, enhance perivascular Aβ clearance, and improve cerebral blood flow, owing principally to the significantly improved cerebral permeation. A Trojan horse can also be equipped with photosensitizers, nanoparticles, quantum dots, or fluorescent molecules to function as multiple targeting theranostic compounds that could be activated following changes in disease-specific processes of the diseased tissue such as pH and protease activity, or exogenous stimuli such as, light. This concept review theorizes the use of receptor-mediated transport-based platforms to transform such novel ideas to engineer systemic and smart Trojan detection or therapeutic probes to advance the neurodegenerative field.
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Affiliation(s)
- Amal A. Aziz
- Sir Wilfrid Laurier Secondary School, Thames Valley District School Board, London, Canada
| | - Rafat A. Siddiqui
- Nutrition Science and Food Chemistry Laboratory, Agricultural Research Station, Virginia State University, Petersburg, VA, USA
| | - Zareen Amtul
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Canada
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18
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Tailoring solulan C24 based niosomes for transdermal delivery of donepezil: In vitro characterization, evaluation of pH sensitivity, and microneedle-assisted Ex vivo permeation studies. J Drug Deliv Sci Technol 2020. [DOI: 10.1016/j.jddst.2020.101945] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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19
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Melatonin regulates Aβ production/clearance balance and Aβ neurotoxicity: A potential therapeutic molecule for Alzheimer's disease. Biomed Pharmacother 2020; 132:110887. [PMID: 33254429 DOI: 10.1016/j.biopha.2020.110887] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disease with multiple predisposing factors and complicated pathogenesis. Aβ peptide is one of the most important pathogenic factors in the etiology of AD. Accumulating evidence indicates that the imbalance of Aβ production and Aβ clearance in the brain of AD patients leads to Aβ deposition and neurotoxic Aβ oligomer formation. Melatonin shows a potent neuroprotective effect and can prevent or slow down the progression of AD, supporting the view that melatonin is a potential therapeutic molecule for AD. Melatonin modulates the regulatory network of secretase expression and affects the function of secretase, thereby inhibiting amyloidogenic APP processing and Aβ production. Additionally, melatonin ameliorates Aβ-induced neurotoxicity and probably promotes Aβ clearance through glymphatic-lymphatic drainage, BBB transportation and degradation pathways. In this review, we summarize and discuss the role of melatonin against Aβ-dependent AD pathogenesis. We explore the potential cellular and molecular mechanisms of melatonin on Aβ production and assembly, Aβ clearance, Aβ neurotoxicity and circadian cycle disruption. We summarize multiple clinical trials of melatonin treatment in AD patients, showing that melatonin has a promising effect on improving sleep quality and cognitive function. This review aims to stimulate further research on melatonin as a potential therapeutic agent for AD.
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20
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Valverde P, Martínez JD, Cañada FJ, Ardá A, Jiménez-Barbero J. Molecular Recognition in C-Type Lectins: The Cases of DC-SIGN, Langerin, MGL, and L-Sectin. Chembiochem 2020; 21:2999-3025. [PMID: 32426893 PMCID: PMC7276794 DOI: 10.1002/cbic.202000238] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 05/19/2020] [Indexed: 12/16/2022]
Abstract
Carbohydrates play a pivotal role in intercellular communication processes. In particular, glycan antigens are key for sustaining homeostasis, helping leukocytes to distinguish damaged tissues and invading pathogens from healthy tissues. From a structural perspective, this cross-talk is fairly complex, and multiple membrane proteins guide these recognition processes, including lectins and Toll-like receptors. Since the beginning of this century, lectins have become potential targets for therapeutics for controlling and/or avoiding the progression of pathologies derived from an incorrect immune outcome, including infectious processes, cancer, or autoimmune diseases. Therefore, a detailed knowledge of these receptors is mandatory for the development of specific treatments. In this review, we summarize the current knowledge about four key C-type lectins whose importance has been steadily growing in recent years, focusing in particular on how glycan recognition takes place at the molecular level, but also looking at recent progresses in the quest for therapeutics.
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Affiliation(s)
- Pablo Valverde
- CIC bioGUNE, Basque Research Technology Alliance, BRTA, Bizkaia Technology park, Building 800, 48160, Derio, Spain
| | - J Daniel Martínez
- CIC bioGUNE, Basque Research Technology Alliance, BRTA, Bizkaia Technology park, Building 800, 48160, Derio, Spain
| | - F Javier Cañada
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Avda Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Ana Ardá
- CIC bioGUNE, Basque Research Technology Alliance, BRTA, Bizkaia Technology park, Building 800, 48160, Derio, Spain
| | - Jesús Jiménez-Barbero
- CIC bioGUNE, Basque Research Technology Alliance, BRTA, Bizkaia Technology park, Building 800, 48160, Derio, Spain
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain
- Department of Organic Chemistry II, Faculty of Science and Technology, UPV-EHU, 48940, Leioa, Spain
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21
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Chandrasekhar G, Rajasekaran R. Investigating the pernicious effects of heparan sulfate in serum amyloid A1 protein aggregation: a structural bioinformatics approach. J Biomol Struct Dyn 2020; 40:1776-1790. [PMID: 33050843 DOI: 10.1080/07391102.2020.1833756] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Amyloid-A mediated (AA) amyloidosis is the pathogenic byproduct of body's prolonged exposure to inflammatory conditions. It is described by the aggregation of mutated/misfolded serum amyloid A1 (SAA1) protein in various tissues and organs. Genetic polymorphism G90D is suspected to cause AA amyloidosis, although the causal mechanism remains cryptic. Recent experimental findings insinuate that heparan sulphate (HS), a glycosaminoglycans, exhibits binding with SAA1 to promote its aggregation. To foster the enhanced binding of HS, we computationally determined the pernicious modifications in G90D mutant SAA1 protein. Also, we examined the influence of HS on the dynamic conformation of mutant SAA1 that could potentially succor amyloidosis. Accordingly, the protein-ligand binding studies indicate that upon SNP G90D, SAA1 protein exhibited an augmented association with HS. Further, the simulation of HS bound mutant SAA1 complex delineates an increase in RMSD, Rg, and RMSF. Also, both RMSD and Rg evinced a fluctuating trajectory. Further, the complex showed increase of beta turn in its secondary structural composition. Additionally, the free energy landscape of mutant SAA1-HS complex posits the occurrence of multiple global minima conformers as opposed to the presence of a single global energy minima conformation in native SAA1 protein. In conclusion, the aforementioned conformational ramifications induced by HS on SAA1 could potentially be the proteopathic incendiary behind AA amyloidosis; this incendiary will need to be considered in future studies for developing effective therapeutics against AA amyloidosis.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- G Chandrasekhar
- Bioinformatics Lab, Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology (Deemed to be University), Vellore, Tamil Nadu, India
| | - R Rajasekaran
- Bioinformatics Lab, Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology (Deemed to be University), Vellore, Tamil Nadu, India
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22
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Li J, Wang X, Shen M, Shi X. Polyethylenimine-Assisted Generation of Optical Nanoprobes for Biosensing Applications. ACS APPLIED BIO MATERIALS 2020; 3:3935-3955. [PMID: 35025470 DOI: 10.1021/acsabm.0c00536] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Detection of analytes in biological systems is pivotal to explore their physiological roles and provide diagnostic and treatment options for related diseases, which however remains a great challenge. Optical nanoprobes that exhibit absorption or fluorescence signal changes in response to the targets of interest have emerged as a versatile class of biosensors in the field. Polyethylenimine (PEI) with abundant amine groups plays indispensable roles in the construction of optical nanoprobes and mediating the sensing processes. After interaction with analytes, PEI-based optical nanoprobes can be induced to form aggregates, be disassembled or separated into individual units, or undergo structure/component alterations. As such, the optical properties of these nanoprobes have corresponding changes, allowing for sensitive and selective detection of a wide variety of analytes in biological environment. Up to now, detections of reactive oxygen species, pH, metal ions, biothiols, neurotransmitters, therapeutic agents, oxygen levels, enzyme activities, and virus/bacteria have been successfully demonstrated using PEI-based optical nanoprobes. Herein, we summarize the recent developments of PEI-based optical nanoprobes for biosensing applications and highlight the probe designs and sensing mechanisms. The existing challenges and prospects regarding biosensing applications of PEI-based optical nanoprobes are also briefly discussed.
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Affiliation(s)
- Jingchao Li
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China
| | - Xiaoying Wang
- Xuhui District Center for Disease Control and Prevention, Shanghai 200237, China
| | - Mingwu Shen
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China
| | - Xiangyang Shi
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China.,CQM-Centro de Quimica da Madeira, Universidade da Madeira, Campus da Penteada, 9020-105 Funchal, Portugal
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23
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Histidine-Lacked Aβ(1–16) Peptides: pH-Dependent Conformational Changes in Metal Ion Binding. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-020-10048-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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24
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Elucidating the Effect of Static Electric Field on Amyloid Beta 1-42 Supramolecular Assembly. J Mol Graph Model 2020; 96:107535. [PMID: 31978828 DOI: 10.1016/j.jmgm.2020.107535] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/06/2019] [Accepted: 01/09/2020] [Indexed: 02/07/2023]
Abstract
Amyloid-β (Aβ) aggregation is recognized to be a key toxic factor in the pathogenesis of Alzheimer disease, which is the most common progressive neurodegenerative disorder. In vitro experiments have elucidated that Aβ aggregation depends on several factors, such as pH, temperature and peptide concentration. Despite the research effort in this field, the fundamental mechanism responsible for the disease progression is still unclear. Recent research has proposed the application of electric fields as a non-invasive therapeutic option leading to the disruption of amyloid fibrils. In this regard, a molecular level understanding of the interactions governing the destabilization mechanism represents an important research advancement. Understanding the electric field effects on proteins, provides a more in-depth comprehension of the relationship between protein conformation and electrostatic dipole moment. The present study focuses on investigating the effect of static Electric Field (EF) on the conformational dynamics of Aβ fibrils by all-atom Molecular Dynamics (MD) simulations. The outcome of this work provides novel insight into this research field, demonstrating how the Aβ assembly may be destabilized by the applied EF.
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Examination of Adsorption Orientation of Amyloidogenic Peptides Over Nano-Gold Colloidal Particle Surfaces. Int J Mol Sci 2019; 20:ijms20215354. [PMID: 31661810 PMCID: PMC6862242 DOI: 10.3390/ijms20215354] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/14/2019] [Accepted: 10/23/2019] [Indexed: 01/12/2023] Open
Abstract
The adsorption of amyloidogenic peptides, amyloid beta 1–40 (Aβ1–40), alpha-synuclein (α-syn), and beta 2 microglobulin (β2m), was attempted over the surface of nano-gold colloidal particles, ranging from d = 10 to 100 nm in diameter (d). The spectroscopic inspection between pH 2 and pH 12 successfully extracted the critical pH point (pHo) at which the color change of the amyloidogenic peptide-coated nano-gold colloids occurred due to aggregation of the nano-gold colloids. The change in surface property caused by the degree of peptide coverage was hypothesized to reflect the ΔpHo, which is the difference in pHo between bare gold colloids and peptide coated gold colloids. The coverage ratio (Θ) for all amyloidogenic peptides over gold colloid of different sizes was extracted by assuming Θ = 0 at ΔpHo = 0. Remarkably, Θ was found to have a nano-gold colloidal size dependence, however, this nano-size dependence was not simply correlated with d. The geometric analysis and simulation of reproducing Θ was conducted by assuming a prolate shape of all amyloidogenic peptides. The simulation concluded that a spiking-out orientation of a prolate was required in order to reproduce the extracted Θ. The involvement of a secondary layer was suggested; this secondary layer was considered to be due to the networking of the peptides. An extracted average distance of networking between adjacent gold colloids supports the binding of peptides as if they are “entangled” and enclosed in an interfacial distance that was found to be approximately 2 nm. The complex nano-size dependence of Θ was explained by available spacing between adjacent prolates. When the secondary layer was formed, Aβ1–40 and α-syn possessed a higher affinity to a partially negative nano-gold colloidal surface. However, β2m peptides tend to interact with each other. This difference was explained by the difference in partial charge distribution over a monomer. Both Aβ1–40 and α-syn are considered to have a partial charge (especially δ+) distribution centering around the prolate axis. The β2m, however, possesses a distorted charge distribution. For a lower Θ (i.e., Θ <0.5), a prolate was assumed to conduct a gyration motion, maintaining the spiking-out orientation to fill in the unoccupied space with a tilting angle ranging between 5° and 58° depending on the nano-scale and peptide coated to the gold colloid.
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Beasley M, Stonebraker AR, Hasan I, Kapp KL, Liang BJ, Agarwal G, Groover S, Sedighi F, Legleiter J. Lipid Membranes Influence the Ability of Small Molecules To Inhibit Huntingtin Fibrillization. Biochemistry 2019; 58:4361-4373. [PMID: 31608620 DOI: 10.1021/acs.biochem.9b00739] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Several diseases, including Alzheimer's disease, Parkinson's disease, and Huntington's disease (HD), are associated with specific proteins aggregating and depositing within tissues and/or cellular compartments. The aggregation of these proteins is characterized by the formation of extended, β-sheet rich fibrils, termed amyloid. In addition, a variety of other aggregate species also form, including oligomers and protofibrils. Specifically, HD is caused by the aggregation of the huntingtin (htt) protein that contains an expanded polyglutamine domain. Due to the link between protein aggregation and disease, small molecule aggregation inhibitors have been pursued as potential therapeutic agents. Two such small molecules are epigallocatechin 3-gallate (EGCG) and curcumin, both of which inhibit the fibril formation of several amyloid-forming proteins. However, amyloid formation is a complex process that is strongly influenced by the protein's environment, leading to distinct aggregation pathways. Thus, changes in the protein's environment may alter the effectiveness of aggregation inhibitors. A well-known modulator of amyloid formation is lipid membranes. Here, we investigated if the presence of lipid vesicles altered the ability of EGCG or curcumin to modulate htt aggregation and influence the interaction of htt with lipid membranes. The presence of 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine or total brain lipid extract vesicles prevented the curcumin from inhibiting htt fibril formation. In contrast, EGCG's inhibition of htt fibril formation persisted in the presence of lipids. Collectively, these results highlight the complexity of htt aggregation and demonstrate that the presence of lipid membranes is a key modifier of the ability of small molecules to inhibit htt fibril formation.
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Affiliation(s)
- Maryssa Beasley
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Alyssa R Stonebraker
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Iraj Hasan
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Kathryn L Kapp
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Barry J Liang
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Garima Agarwal
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Sharon Groover
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Faezeh Sedighi
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States.,Rockefeller Neurosciences Institute , West Virginia University , 1 Medical Center Drive , P.O. Box 9303, Morgantown , West Virginia 26505 , United States.,Department of Neuroscience , West Virginia University , 1 Medical Center Drive , P.O. Box 9303, Morgantown , West Virginia 26505 , United States
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Owen MC, Gnutt D, Gao M, Wärmländer SKTS, Jarvet J, Gräslund A, Winter R, Ebbinghaus S, Strodel B. Effects of in vivo conditions on amyloid aggregation. Chem Soc Rev 2019; 48:3946-3996. [PMID: 31192324 DOI: 10.1039/c8cs00034d] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
One of the grand challenges of biophysical chemistry is to understand the principles that govern protein misfolding and aggregation, which is a highly complex process that is sensitive to initial conditions, operates on a huge range of length- and timescales, and has products that range from protein dimers to macroscopic amyloid fibrils. Aberrant aggregation is associated with more than 25 diseases, which include Alzheimer's, Parkinson's, Huntington's, and type II diabetes. Amyloid aggregation has been extensively studied in the test tube, therefore under conditions that are far from physiological relevance. Hence, there is dire need to extend these investigations to in vivo conditions where amyloid formation is affected by a myriad of biochemical interactions. As a hallmark of neurodegenerative diseases, these interactions need to be understood in detail to develop novel therapeutic interventions, as millions of people globally suffer from neurodegenerative disorders and type II diabetes. The aim of this review is to document the progress in the research on amyloid formation from a physicochemical perspective with a special focus on the physiological factors influencing the aggregation of the amyloid-β peptide, the islet amyloid polypeptide, α-synuclein, and the hungingtin protein.
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Affiliation(s)
- Michael C Owen
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
| | - David Gnutt
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, 38106 Braunschweig, Germany and Lead Discovery Wuppertal, Bayer AG, 42096 Wuppertal, Germany
| | - Mimi Gao
- Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Str. 4a, 44227 Dortmund, Germany and Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, 65926 Frankfurt, Germany
| | - Sebastian K T S Wärmländer
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius väg 16C, 106 91 Stockholm, Sweden
| | - Jüri Jarvet
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius väg 16C, 106 91 Stockholm, Sweden
| | - Astrid Gräslund
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius väg 16C, 106 91 Stockholm, Sweden
| | - Roland Winter
- Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Str. 4a, 44227 Dortmund, Germany
| | - Simon Ebbinghaus
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, 38106 Braunschweig, Germany
| | - Birgit Strodel
- Institute of Complex Systems: Structural Biochemistry, Forschungszentrum Jülich, 42525 Jülich, Germany. and Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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Protein misfolding, aggregation and mechanism of amyloid cytotoxicity: An overview and therapeutic strategies to inhibit aggregation. Int J Biol Macromol 2019; 134:1022-1037. [PMID: 31128177 DOI: 10.1016/j.ijbiomac.2019.05.109] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/18/2019] [Accepted: 05/18/2019] [Indexed: 12/18/2022]
Abstract
Protein and peptides are converted from their soluble forms into highly ordered fibrillar aggregates under various conditions inside the cell. Such transitions confer diverse neurodegenerative diseases including Alzheimer's disease, Huntington's disease Prion's disease, Parkinson's disease, polyQ and share abnormal folding of potentially cytotoxic protein species linked with degeneration and death of precise neuronal populations. Presently, major advances are made to understand and get detailed insight into the structural basis and mechanism of amyloid formation, cytotoxicity and therapeutic approaches to combat them. Here we highlight classifies and summarizes the detailed overview of protein misfolding and aggregation at their molecular level including the factors that promote protein aggregation under in vivo and in vitro conditions. In addition, we describe the recent technologies that aid the characterization of amyloid aggregates along with several models that might be responsible for amyloid induced cytotoxicity to cells. Overview on the inhibition of amyloidosis by targeting different small molecules (both natural and synthetic origin) have been also discussed, that provides important approaches to identify novel targets and develop specific therapeutic strategies to combat protein aggregation related neurodegenerative diseases.
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Saikia J, Pandey G, Sasidharan S, Antony F, Nemade HB, Kumar S, Chaudhary N, Ramakrishnan V. Electric Field Disruption of Amyloid Aggregation: Potential Noninvasive Therapy for Alzheimer's Disease. ACS Chem Neurosci 2019; 10:2250-2262. [PMID: 30707008 DOI: 10.1021/acschemneuro.8b00490] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The aggregation of β-amyloid peptides is a key event in the formative stages of Alzheimer's disease. Promoting folding and inhibiting aggregation was reported as an effective strategy in reducing Aβ-elicited toxicity. This study experimentally investigates the influence of the external electric field (EF) and magnetic field (MF) of varying strengths on the in vitro fibrillogenesis of hydrophobic core sequence, Aβ16-22, and its parent peptide, Aβ1-42. Biophysical methods such as ThT fluorescence, static light scattering, circular dichroism, and infrared spectroscopy suggest that EF has a stabilizing effect on the secondary structure, initiating a conformational switch of Aβ16-22 and Aβ1-42 from β to non-β conformation. This observation was further corroborated by dynamic light scattering and transmission electron microscopic studies. To mimic in vivo conditions, we repeated ThT fluorescence assay with Aβ1-42 in human cerebrospinal fluid to verify EF-mediated modulation. The self-seeding of Aβ1-42 and cross-seeding with Aβ1-40 to verify that the autocatalytic amplification of self-assembly as a result of secondary nucleation also yields comparable results in EF-exposed and unexposed samples. Aβ-elicited toxicity of EF-treated samples in two neuroblastoma cell lines (SH-SY5Y and IMR-32) and human embryonic kidney cell line (HEK293) were found to be 15-38% less toxic than the EF untreated ones under identical conditions. Experiments with fluorescent labeled Aβ1-42 to correlate reduced cytotoxicity and cell internalization suggest a comparatively smaller uptake of the EF-treated peptides. Our results provide a scientific roadmap for future noninvasive, therapeutic solutions for the treatment of Alzheimer's disease.
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Qi R, Liu J, Zhang N, Ji X, Han Y, Wang Y. Assembly and Evolution of Gemini-Type Peptide Amphiphile with a Di-Lysine Spacer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6154-6160. [PMID: 30983363 DOI: 10.1021/acs.langmuir.9b00688] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Peptide amphiphiles (PAs) can self-assemble into a variety of supramolecular structures with excellent biofunctions. However, their assembly with time has rarely been observed and reported. Here, we find that a novel gemini-type PA [12-(Lys)2-12], taking two lysine (Lys) groups as the spacer, shows an obvious assembly and evolution process with time. Driven by the strong hydrophobic interaction between the alkyl chains as well as the electrostatic force and hydrogen bonding among the peptide spacers, the 12-(Lys)2-12 molecules first self-assemble into vesicles and then transform into fibrils, ribbons, and belts with time. If replacing the -(Lys)2- spacer with four lysine groups [-(Lys)4-] or two glutamic acid groups [-(Glu)2-], the PA molecules do not show the aggregate growth with time. This indicates that the lysine structure and its length are important structural factors contributing to the dynamic aggregate evolution behavior. More interestingly, this assembly and evolution behavior is highly dependent on 12-(Lys)2-12 concentration. Only in the proper concentration region (0.5-0.7 mM), the self-assembly displays the aggregate growth with time. At lower or higher concentrations, the aggregate growth is largely delayed or inhibited. Moreover, we also find that the aggregate growth of 12-(Lys)2-12 is related to the fibril solubilization temperature ( Tf→s). The faster aggregate growth occurs when the temperature is much lower than Tf→s. This work gains new insights into the evolution of the self-assembling structures of peptide amphiphiles.
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Affiliation(s)
- Ruilian Qi
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Jian Liu
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Na Zhang
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | | | | | - Yilin Wang
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
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Abstract
AbstractThe aggregation of the 11 residue long NACore peptide segment of α-synuclein (68-GAVVTGVTAVA-78) has been investigated using a combination of cryogenic transmission electron microscopy (cryo-TEM), small- and wide-angle X-ray scattering, and spectroscopy techniques. The aqueous peptide solubility is pH dependent, and aggregation was triggered by a pH quench from pH 11.3 to approximately pH 8 or 6, where the average peptide net charge is weakly negative (pH 8), or essentially zero (pH 6). Cryo-TEM shows the presence of long and stiff fibrillar aggregates at both pH, that are built up from β-sheets, as demonstrated by circular dichroism spectroscopy and thioflavin T fluorescence. The fibrils are crystalline, with a wide angle X-ray diffraction pattern that is consistent with a previously determined crystal structure of NACore. Of particular note is the cryo-TEM observation of small globular shaped aggregates, of the order of a few nanometers in size, adsorbed onto the surface of already formed fibrils at pH 6. The fibrillation kinetics is slow, and occurs on the time scale of days. Similarly slow kinetics is observed at both pH, but slightly slower at pH 6, even though the peptide solubility is here expected to be lower. The observation of the small globular shaped aggregates, together with the associated kinetics, could be highly relevant in relation to mechanisms of secondary nucleation and oligomer formation in amyloid systems.
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32
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Jas GS, Childs EW, Kuczera K. Kinetic pathway analysis of an α-helix in two protonation states: Direct observation and optimal dimensionality reduction. J Chem Phys 2019; 150:074902. [PMID: 30795683 DOI: 10.1063/1.5082192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Thermodynamically stable conformers of secondary structural elements make a stable tertiary/quaternary structure that performs its proper biological function efficiently. Formation mechanisms of secondary and tertiary/quaternary structural elements from the primary structure are driven by the kinetic properties of the respective systems. Here we have carried out thermodynamic and kinetic characterization of an alpha helical heteropeptide in two protonation states, created with the addition and removal of a proton involving a single histidine residue in the primary structure. Applying far-UV circular dichroism spectroscopy, the alpha helix is observed to be significantly more stable in the deprotonated state. Nanosecond laser temperature jump spectroscopy monitoring time-resolved tryptophan fluorescence on the protonated conformer is carried out to measure the kinetics of this system. The measured relaxation rates at a final temperature between 296K and 314 K generated a faster component of 20 ns-11 ns and a slower component of 314 ns-198 ns. Atomically detailed characterization of the helix-coil kinetic pathways is performed based on all-atom molecular dynamics trajectories of the two conformers. Application of clustering and kinetic coarse-graining with optimum dimensionality reduction produced description of the trajectories in terms of kinetic models with two to five states. These models include aggregate states corresponding to helix, coil, and intermediates. The "coil" state involves the largest number of conformations, consistent with the expected high entropy of this structural ensemble. The "helix" aggregate states are found to be mixed with the full helix and partially folded forms. The experimentally observed higher helix stability in the deprotonated form of the alpha helical heteropeptide is reflected in the nature of the "helix" aggregate state arising from the kinetic model. In the protonated form, the "coil" state exhibits the lowest free energy and longest lifetime, while in the deprotonated form, it is the "helix" that is found to be most stable. Overall, the coarse grained models suggest that the protonation of a single histidine residue in the primary structure induces significant changes in the free energy landscape and kinetic network of the studied helix-forming heteropeptide.
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Affiliation(s)
- Gouri S Jas
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047, USA
| | - Ed W Childs
- Department of Surgery, Morehouse School of Medicine, Atlanta, Georgia 30310, USA
| | - Krzysztof Kuczera
- Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66047, USA
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Gekko K. Synchrotron-radiation vacuum-ultraviolet circular dichroism spectroscopy in structural biology: an overview. Biophys Physicobiol 2019; 16:41-58. [PMID: 30923662 PMCID: PMC6435020 DOI: 10.2142/biophysico.16.0_41] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 01/13/2019] [Indexed: 12/01/2022] Open
Abstract
Circular dichroism spectroscopy is widely used for analyzing the structures of chiral molecules, including biomolecules. Vacuum-ultraviolet circular dichroism (VUVCD) spectroscopy using synchrotron radiation can extend the short-wavelength limit into the vacuum-ultraviolet region (down to ~160 nm) to provide detailed and new information about the structures of biomolecules in combination with theoretical analysis and bioinformatics. The VUVCD spectra of saccharides can detect the high-energy transitions of chromophores such as hydroxy and acetal groups, disclosing the contributions of inter- or intramolecular hydrogen bonds to the equilibrium configuration of monosaccharides in aqueous solution. The roles of hydration in the fluctuation of the dihedral angles of carboxyl and amino groups of amino acids can be clarified by comparing the observed VUVCD spectra with those calculated theoretically. The VUVCD spectra of proteins markedly improves the accuracy of predicting the contents and number of segments of the secondary structures, and their amino acid sequences when combined with bioinformatics, for not only native but also nonnative and membrane-bound proteins. The VUVCD spectra of nucleic acids confirm the contributions of the base composition and sequence to the conformation in comparative analyses of synthetic poly-nucleotides composed of selected bases. This review surveys these recent applications of synchrotron-radiation VUVCD spectroscopy in structural biology, covering saccharides, amino acids, proteins, and nucleic acids.
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Affiliation(s)
- Kunihiko Gekko
- Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-0046, Japan
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Jahanbin F, Bozorgmehr MR, Morsali A, Beyramabadi SA. The effect of different alcohols on the Asp23-Lys28 and Asp23-Ala42 salt bridges of the most effective peptide in Alzheimer's disease: Molecular dynamics viewpoints. J Mol Graph Model 2019; 86:199-208. [DOI: 10.1016/j.jmgm.2018.10.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 10/21/2018] [Accepted: 10/22/2018] [Indexed: 11/27/2022]
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Miao Q, Pu K. Organic Semiconducting Agents for Deep-Tissue Molecular Imaging: Second Near-Infrared Fluorescence, Self-Luminescence, and Photoacoustics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1801778. [PMID: 30058244 DOI: 10.1002/adma.201801778] [Citation(s) in RCA: 348] [Impact Index Per Article: 58.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/17/2018] [Indexed: 05/05/2023]
Abstract
Optical imaging has played a pivotal role in biology and medicine, but it faces challenges of relatively low tissue penetration and poor signal-to-background ratio due to light scattering and tissue autofluorescence. To overcome these issues, second near-infrared fluorescence, self-luminescence, and photoacoustic imaging have recently emerged, which utilize an optical region with reduced light-tissue interactions, eliminate real-time light excitation, and detect acoustic signals with negligible attenuation, respectively. Because there are only a few endogenous molecules absorbing or emitting above the visible region, development of contrast agents is essential for those deep-tissue optical imaging modalities. Organic semiconducting agents with π-conjugated frameworks can be synthesized to meet different optical imaging requirements due to their easy chemical modification and legible structure-property relation. Herein, the deep-tissue optical imaging applications of organic semiconducting agents including small-molecule agents and nanoparticle derivatives are summarized. In particular, the molecular engineering and nanoformulation approaches to further improve the tissue penetration and detection sensitivity of these optical imaging modalities are highlighted. Finally, current challenges and potential opportunities in this emerging subfield of biomedical imaging are discussed.
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Affiliation(s)
- Qingqing Miao
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637457, Singapore
| | - Kanyi Pu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637457, Singapore
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Brumshtein B, Esswein SR, Sawaya MR, Rosenberg G, Ly AT, Landau M, Eisenberg DS. Identification of two principal amyloid-driving segments in variable domains of Ig light chains in systemic light-chain amyloidosis. J Biol Chem 2018; 293:19659-19671. [PMID: 30355736 DOI: 10.1074/jbc.ra118.004142] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 10/18/2018] [Indexed: 11/06/2022] Open
Abstract
Systemic light-chain amyloidosis (AL) is a human disease caused by overexpression of monoclonal immunoglobulin light chains that form pathogenic amyloid fibrils. These amyloid fibrils deposit in tissues and cause organ failure. Proteins form amyloid fibrils when they partly or fully unfold and expose segments capable of stacking into β-sheets that pair and thereby form a tight, dehydrated interface. These structures, termed steric zippers, constitute the spines of amyloid fibrils. Here, using a combination of computational (with ZipperDB and Boston University ALBase), mutational, biochemical, and protein structural analyses, we identified segments within the variable domains of Ig light chains that drive the assembly of amyloid fibrils in AL. We demonstrate that there are at least two such segments and that each one can drive amyloid fibril assembly independently of the other. Our analysis revealed that peptides derived from these segments form steric zippers featuring a typical dry interface with high-surface complementarity and occupy the same spatial location of the Greek-key immunoglobulin fold in both λ and κ variable domains. Of note, some predicted steric-zipper segments did not form amyloid fibrils or assembled into fibrils only when removed from the whole protein. We conclude that steric-zipper propensity must be experimentally validated and that the two segments identified here may represent therapeutic targets. In addition to elucidating the molecular pathogenesis of AL, these findings also provide an experimental approach for identifying segments that drive fibril formation in other amyloid diseases.
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Affiliation(s)
- Boris Brumshtein
- From the Departments of Biological Chemistry and Chemistry and Biochemistry, Howard Hughes Medical Institute, UCLA-DOE Institute, UCLA, Los Angeles, California 90095 and
| | - Shannon R Esswein
- From the Departments of Biological Chemistry and Chemistry and Biochemistry, Howard Hughes Medical Institute, UCLA-DOE Institute, UCLA, Los Angeles, California 90095 and
| | - Michael R Sawaya
- From the Departments of Biological Chemistry and Chemistry and Biochemistry, Howard Hughes Medical Institute, UCLA-DOE Institute, UCLA, Los Angeles, California 90095 and
| | - Gregory Rosenberg
- From the Departments of Biological Chemistry and Chemistry and Biochemistry, Howard Hughes Medical Institute, UCLA-DOE Institute, UCLA, Los Angeles, California 90095 and
| | - Alan T Ly
- From the Departments of Biological Chemistry and Chemistry and Biochemistry, Howard Hughes Medical Institute, UCLA-DOE Institute, UCLA, Los Angeles, California 90095 and
| | - Meytal Landau
- the Department of Biology, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - David S Eisenberg
- From the Departments of Biological Chemistry and Chemistry and Biochemistry, Howard Hughes Medical Institute, UCLA-DOE Institute, UCLA, Los Angeles, California 90095 and
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37
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Jas GS, Kuczera K. Deprotonation of a Single Amino Acid Residue Induces Significant Stability in an α-Helical Heteropeptide. J Phys Chem B 2018; 122:11508-11518. [PMID: 30339390 DOI: 10.1021/acs.jpcb.8b07418] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Stability of secondary structural elements is an integral component of a structurally stable protein. Presence of protons in the residue sequence and their immediate environment play a significant role in conformational stability. In this study, we show that removing a proton from a single amino acid residue significantly increases the stability of an α-helical heteropeptide in comparison with the unprotonated form. Far-UV circular dichroism spectroscopy, fluorescence spectroscopy, fluorescence energy transfer measurements, and over 10 μs of all-atom molecular dynamics simulations are used to provide an atomically detailed characterization of this event. There is a single histidine residue in the studied α-helical peptide sequence toward the N-terminal that interacts with a tryptophan located four residues away and quenches the fluorescence when protonated. Removing a proton from this histidine residue dequenches the tryptophan fluorescence and contributes to a significant increase in the helix stability. Atomically detailed analysis of individual residue conformations shows that the protonated histidine tends to be in closer proximity to the tryptophan, which correlates with higher helix content in the N and C termini and lower helix content in the central region of the peptide. In the presence of a neutral histidine, when tryptophan fluorescence is no longer quenched and histidine moves further away from tryptophan, the helix content remains mostly unchanged in the N-and-C termini and significantly increases in the central region. Our results strongly suggest that interactions of the tryptophan with a protonated histidine downregulate the helix population in the central segment of the helical structure compared to a neutral histidine residue. Upregulation of helix population of the central segment of this α-helical heteropeptide in the presence of a neutral histidine residue significantly increases the peptide structural stability.
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Affiliation(s)
| | - Krzysztof Kuczera
- Department of Chemistry , The University of Kansas , Lawrence , Kansas 66045 , United States
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Deshmukh SS, Magcalas FW, Kalbfleisch KN, Carpick BW, Kirkitadze MD. Tuberculosis vaccine candidate: Characterization of H4-IC31 formulation and H4 antigen conformation. J Pharm Biomed Anal 2018; 157:235-243. [PMID: 29866391 DOI: 10.1016/j.jpba.2018.05.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 05/28/2018] [Accepted: 05/30/2018] [Indexed: 12/01/2022]
Abstract
Tuberculosis (TB) is one of the leading causes of death worldwide, making the development of effective TB vaccines a global priority. A TB vaccine consisting of a recombinant fusion protein, H4, combined with a novel synthetic cationic adjuvant, IC31®, is currently being developed. The H4 fusion protein consists of two immunogenic mycobacterial antigens, Ag85 B and TB10.4, and the IC31® adjuvant is a mixture of KLK, a leucine-rich peptide (KLKL5KLK), and the oligodeoxynucleotide ODN1a, a TLR9 ligand. However, efficient and robust methods for assessing these formulated components are lacking. Here, we developed and optimized phase analysis light scattering (PALS), electrical sensing zone (ESZ), and Raman, FTIR, and CD spectroscopy methods to characterize the H4-IC31 vaccine formulation. PALS-measured conductivity and zeta potential values could differentiate between the similarly sized particles of IC31® adjuvant and the H4-IC31 vaccine candidate and could thereby serve as a control during vaccine formulation. In addition, zeta potential is indicative of the adjuvant to antigen ratio which is the key in the immunomodulatory response of the vaccine. ESZ was used as an orthogonal method to measure IC31® and H4-IC31 particle sizes. Raman, FTIR, and CD spectroscopy revealed structural changes in H4 protein and IC31® adjuvant, inducing an increase in both the β-sheet and random coil content as a result of adsorption. Furthermore, nanoDSF showed changes in the tertiary structure of H4 protein as a result of adjuvantation to IC31®. Our findings demonstrate the applicability of biophysical methods to characterize vaccine components in the final H4-IC31 drug product without the requirement for desorption.
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Affiliation(s)
- Sasmit S Deshmukh
- Sanofi Pasteur Ltd., 1755 Steeles Avenue West, Toronto, ON, M2R 3T4, Canada; SGS Canada, Biopharmaceutical Services, 6490 Vipond Drive, Mississauga, ON, L5T 1W8, Canada
| | - Federico Webster Magcalas
- Sanofi Pasteur Ltd., 1755 Steeles Avenue West, Toronto, ON, M2R 3T4, Canada; Biotechnology Advanced Program, Seneca College, 70 The Pond Road, Toronto, ON, M3J 3M6, Canada
| | - Kristen N Kalbfleisch
- Sanofi Pasteur Ltd., 1755 Steeles Avenue West, Toronto, ON, M2R 3T4, Canada; Biotechnology Advanced Program, Seneca College, 70 The Pond Road, Toronto, ON, M3J 3M6, Canada
| | - Bruce W Carpick
- Sanofi Pasteur Ltd., 1755 Steeles Avenue West, Toronto, ON, M2R 3T4, Canada
| | - Marina D Kirkitadze
- Sanofi Pasteur Ltd., 1755 Steeles Avenue West, Toronto, ON, M2R 3T4, Canada.
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39
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de Freitas MS, Rezaei Araghi R, Brandenburg E, Leiterer J, Emmerling F, Folmert K, Gerling-Driessen UIM, Bardiaux B, Böttcher C, Pagel K, Diehl A, Berlepsch HV, Oschkinat H, Koksch B. The protofilament architecture of a de novo designed coiled coil-based amyloidogenic peptide. J Struct Biol 2018; 203:263-272. [PMID: 29857134 DOI: 10.1016/j.jsb.2018.05.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 05/25/2018] [Accepted: 05/28/2018] [Indexed: 01/15/2023]
Abstract
Amyloid fibrils are polymers formed by proteins under specific conditions and in many cases they are related to pathogenesis, such as Parkinson's and Alzheimer's diseases. Their hallmark is the presence of a β-sheet structure. High resolution structural data on these systems as well as information gathered from multiple complementary analytical techniques is needed, from both a fundamental and a pharmaceutical perspective. Here, a previously reported de novo designed, pH-switchable coiled coil-based peptide that undergoes structural transitions resulting in fibril formation under physiological conditions has been exhaustively characterized by transmission electron microscopy (TEM), cryo-TEM, atomic force microscopy (AFM), wide-angle X-ray scattering (WAXS) and solid-state NMR (ssNMR). Overall, a unique 2-dimensional carpet-like assembly composed of large coexisiting ribbon-like, tubular and funnel-like structures with a clearly resolved protofilament substructure is observed. Whereas electron microscopy and scattering data point somewhat more to a hairpin model of β-fibrils, ssNMR data obtained from samples with selectively labelled peptides are in agreement with both, hairpin structures and linear arrangements.
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Affiliation(s)
- Mônica Santos de Freitas
- Leibniz-Institut für Molekulare Pharmakologie, Department NMR-Supported Structural Biology, Robert-Rössle-Strasse 10, 13125 Berlin, Germany; Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany; Universidade Federal do Rio de Janeiro, Instituto de Bioquímica Médica Leopoldo de Meis, Centro Nacional de Biologia Estrutural e Bioimagem, Av. Carlos Chagas Filho 373, Rio de Janeiro, Brazil
| | - Raheleh Rezaei Araghi
- Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany
| | - Enrico Brandenburg
- Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany
| | - Jork Leiterer
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Str. 11, 12489 Berlin, Germany
| | - Franziska Emmerling
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Str. 11, 12489 Berlin, Germany
| | - Kristin Folmert
- Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany
| | - Ulla I M Gerling-Driessen
- Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany
| | - Benjamin Bardiaux
- Institut Pasteur, Unité de Bioinformatique Structurale, CNRS UMR 3528, 75015 Paris, France
| | - Christoph Böttcher
- Freie Universität Berlin, Research Center for Electron Microscopy, Fabeckstrasse 36a, 14195 Berlin, Germany
| | - Kevin Pagel
- Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany
| | - Anne Diehl
- Leibniz-Institut für Molekulare Pharmakologie, Department NMR-Supported Structural Biology, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Hans V Berlepsch
- Freie Universität Berlin, Research Center for Electron Microscopy, Fabeckstrasse 36a, 14195 Berlin, Germany
| | - Hartmut Oschkinat
- Leibniz-Institut für Molekulare Pharmakologie, Department NMR-Supported Structural Biology, Robert-Rössle-Strasse 10, 13125 Berlin, Germany; Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany.
| | - Beate Koksch
- Freie Universität Berlin, Department of Chemistry and Biochemistry, Takustrasse 3, 14195 Berlin, Germany.
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40
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Galzitskaya OV, Selivanova OM. Rosetta Stone for Amyloid Fibrils: The Key Role of Ring-Like Oligomers in Amyloidogenesis. J Alzheimers Dis 2018; 59:785-795. [PMID: 28671122 DOI: 10.3233/jad-170230] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Deeper understanding of processes of protein misfolding, aggregation, formation of oligomers, protofibrils, and fibrils is crucial for the development of future medicine in treatment of amyloid-related diseases. While numerous reports illuminate the field, the above processes are extremely complex, as they depend on many varying parameters, such as the peptide concentration, temperature, pH, presence of metal ions, lipids, and organic solvents. Different mechanisms of amyloid fibril formation have been proposed, but the process of the oligomer-to-fibril transition is the least agreed upon. Our studies of a number of amyloidogenic proteins and peptides (insulin, Aβ peptides, the Bgl2 protein from the yeast cell wall), as well as their amyloidogenic fragments, have allowed us to propose a model of the fibril structure generation. We have found that the main building block of fibrils of any morphology is a ring-like oligomer. The varying models of interaction of ring oligomers with each other revealed in our studies make it possible to explain their polymorphism. Crucially, the amino acid sequence determines the oligomer structure for the given protein/peptide.
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Affiliation(s)
- Oxana V Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russia
| | - Olga M Selivanova
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russia
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41
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Amyloid fibrillation of an intrinsically disordered plant phloem protein AtPP16-1 under acidic condition. Biophys Chem 2018; 237:1-8. [PMID: 29605501 DOI: 10.1016/j.bpc.2018.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/22/2018] [Accepted: 03/22/2018] [Indexed: 12/25/2022]
Abstract
Arabidopsis thaliana Phloem Protein 16-1 (AtPP16-1) is a 156-residue intrinsically disordered nucleic acid binding protein which is putatively involved in long-distance systemic transport of RNA to budding regions in plants. Dimerization or oligomerization of the protein at pH higher than about 4.1 leaves no apolar surface exposed for interaction with the dye 8-Anilinonaphthalene-1-sulfonate (ANS). The most stable monomeric state is found near pH 4 where the structure of the protein is determined to have three short β-strands and a single α-helix. By surveying the pH-dependent propensity of fibrillation we find the protein enters the amyloidogenic state at pH 2, 60 °C. The reaction product is not amorphous aggregate, but simple amyloid fibrils with sparse or no branching. The mean diameters of the fibril population scaled from AFM images are 13.2 and 21.2 nm for precursor aggregates (PA) and proto- or elongated fibrils, respectively. These values are somewhat larger than the fibril diameters generally cited, and the reason could be larger lateral association for both PA and protofibrils. The protein AtPP16-1 is strictly pH-selective in terms of its structure and stability, and the solution structure is known at pH 4. Under the conditions of pH 2 used here for fibrillation, the protein retains substantial secondary structure. Even if the pH and temperature conditions used for fibrillation are hardly physiological, there is a finite possibility that some aggregation of AtPP16-1 would occur in vivo, as the case of transglutaminase aggregates in the chloroplast of transplastomic plants, for example. The pH related problem has been discussed in detail, but the questions emanating are: do phloem proteins fibrillate in vivo, and if so what implication fibrillation has for plant physiology?
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42
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Zhao W, Ai H. Effect of pH on Aβ 42 Monomer and Fibril-like Oligomers-Decoding in Silico of the Roles of pK Values of Charged Residues. Chemphyschem 2018; 19:1103-1116. [PMID: 29380494 DOI: 10.1002/cphc.201701384] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Indexed: 01/10/2023]
Abstract
Amyloid beta-peptide (Aβ) is the key to developing Alzheimer's disease. Experiments have confirmed that different acidity influences directly not only the structural morphology and population of Aβ oligomers, but also the toxicity. The atomic-level association between the pH, charged residues, and Aβ properties remains obscure. Herein, conformational changes of Aβ42 monomer, fibril-like trimer, and pentamer in the medium pH range of 4.0-7.5 are studied. The results reveal that, as the pH changes from 7.5 to the isoelectric pH, His6, His13, and His14 are protonated in turn, successively approach the center of mass of folded Aβ monomer, trigger ionic interactions and changes of neighboring turns (Asp7-Ser8, His14-Lys16) and even a distant one (Leu34-Met35), as well as concomitant changes of secondary structure, and promote the conformation transition from unfolded to folded. This observation discloses that protonation can convert these charged residues from originally hydrophilic to "hydrophobic-like". For fibril-like oligomers, the pH susceptibility essentially stems from the pK values of charged residues in the context of the Aβ fibril, and in turn one can predict the dynamic behavior of these residues in the processes of dissociation or stabilization of a fibril by comparing the pK values of residues involved in salt bridges in the normal state with those in the current context. This idea is justified by two fibril models and appears to be applicable to other peptides and their fibril systems.
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Affiliation(s)
- Wei Zhao
- Shandong Provincial Key Laboratory, of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, P. R. China
| | - Hongqi Ai
- Shandong Provincial Key Laboratory, of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, P. R. China
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43
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Selivanova OM, Surin AK, Ryzhykau YL, Glyakina AV, Suvorina MY, Kuklin AI, Rogachevsky VV, Galzitskaya OV. To Be Fibrils or To Be Nanofilms? Oligomers Are Building Blocks for Fibril and Nanofilm Formation of Fragments of Aβ Peptide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:2332-2343. [PMID: 29338255 DOI: 10.1021/acs.langmuir.7b03393] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
To identify the key stages in the amyloid fibril formation we studied the aggregation of amyloidogenic fragments of Aβ peptide, Aβ(16-25), Aβ(31-40), and Aβ(33-42), using the methods of electron microscopy, X-ray analysis, mass spectrometry, and structural modeling. We have found that fragments Aβ(31-40) and Aβ(33-42) form amyloid fibrils in the shape of bundles and ribbons, while fragment Aβ(16-25) forms only nanofilms. We are the first who performed 2D reconstruction of amyloid fibrils by the Markham rotation technique on electron micrographs of negatively stained fragments of Aβ peptide. Combined analysis of the data allows us to speculate that both the fibrils and the films are formed via association of ring-shaped oligomers with the external diameter of about 6 to 7 nm, the internal diameter of 2 to 3 nm, and the height of ∼3 nm. We conclude that such oligomers are the main building blocks in fibrils of any morphology. The interaction of ring oligomers with each other in different ways makes it possible to explain their polymorphism. The new mechanism of polymerization of amyloidogenic proteins and peptides, described here, could stimulate new approaches in the development of future therapeutics for the treatment of amyloid-related diseases.
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Affiliation(s)
- Olga M Selivanova
- Institute of Protein Research, Russian Academy of Sciences , Pushchino 142290, Russia
| | - Alexey K Surin
- Institute of Protein Research, Russian Academy of Sciences , Pushchino 142290, Russia
- State Research Center for Applied Microbiology & Biotechnology , Obolensk 142279, Russia
| | - Yury L Ryzhykau
- Moscow Institute of Physics and Technology , Dolgoprudny 141701, Russian Federation
| | - Anna V Glyakina
- Institute of Protein Research, Russian Academy of Sciences , Pushchino 142290, Russia
- Institute of Mathematical Problems of Biology RAS, Keldysh Institute of Applied Mathematics of Russian Academy of Sciences , Pushchino 142290, Russia
| | - Mariya Yu Suvorina
- Institute of Protein Research, Russian Academy of Sciences , Pushchino 142290, Russia
| | - Alexander I Kuklin
- Moscow Institute of Physics and Technology , Dolgoprudny 141701, Russian Federation
- Joint Institute for Nuclear Research , Dubna 141980, Russian Federation
| | - Vadim V Rogachevsky
- Institute of Cell Biophysics, Russian Academy of Sciences , Pushchino 142290, Russia
| | - Oxana V Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences , Pushchino 142290, Russia
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44
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Auer S. Simple Model of the Effect of Solution Conditions on the Nucleation of Amyloid Fibrils. J Phys Chem B 2017; 121:8893-8901. [DOI: 10.1021/acs.jpcb.7b05400] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stefan Auer
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
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45
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Lyu Y, Pu K. Recent Advances of Activatable Molecular Probes Based on Semiconducting Polymer Nanoparticles in Sensing and Imaging. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2017; 4:1600481. [PMID: 28638783 PMCID: PMC5473328 DOI: 10.1002/advs.201600481] [Citation(s) in RCA: 156] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 12/29/2016] [Indexed: 05/21/2023]
Abstract
Molecular probes that change their signals in response to the target of interest have a critical role in fundamental biology and medicine. Semiconducting polymer nanoparticles (SPNs) have recently emerged as a new generation of purely organic photonic nanoagents with desirable properties for biological applications. In particular, tunable optical properties of SPNs allow them to be developed into photoluminescence, chemiluminescence, and photoacoustic probes, wherein SPNs usually serve as the energy donor and internal reference for luminescence and photoacoustic probes, respectively. Moreover, facile surface modification and intraparticle engineering provide the versatility to make them responsive to various biologically and pathologically important substances and indexes including small-molecule mediators, proteins, pH and temperature. This article focuses on recent advances in the development of SPN-based activatable molecular probes for sensing and imaging. The designs and applications of these probes are discussed in details, and the present challenges to further advance them into life science are also analyzed.
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Affiliation(s)
- Yan Lyu
- School of Chemical and Biomedical EngineeringNanyang Technological University70 Nanyang DriveSingapore637457
| | - Kanyi Pu
- School of Chemical and Biomedical EngineeringNanyang Technological University70 Nanyang DriveSingapore637457
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46
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Diaz-Espinoza R, Nova E, Monasterio O. Overcoming electrostatic repulsions during amyloid assembly: Effect of pH and interaction with divalent metals using model peptides. Arch Biochem Biophys 2017; 621:46-53. [DOI: 10.1016/j.abb.2017.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/06/2017] [Accepted: 03/09/2017] [Indexed: 12/17/2022]
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47
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Cui D, Xie C, Pu K. Development of Semiconducting Polymer Nanoparticles for Photoacoustic Imaging. Macromol Rapid Commun 2017; 38. [PMID: 28401627 DOI: 10.1002/marc.201700125] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 03/23/2017] [Indexed: 01/01/2023]
Abstract
Semiconducting polymer nanoparticles (SPNs) have evolved into a new class of photonic materials with great potential for biomedical applications. Depending on the polymer structures, SPNs can be developed into optical agents for fluorescence and chemiluminescence imaging, photosensitizers for photodynamic therapy, and heat converters for photothermal therapy. In this feature article, recent work is summarized on the development of SPNs for in vivo photoacoustic (PA) imaging, a state-of-the-art imaging modality that converts light energy into mechanical acoustic waves to provide deep tissue penetration. The structure-property relationship and doping approaches are discussed to reveal the importance of promoting nonradiative decay in amplifying the PA brightness of SPNs. Moreover, their imaging applications, including lymph node mapping, tumor imaging, and monitoring of pathological indexes, are highlighted. These studies demonstrate that SPNs can serve as versatile PA agents for advanced molecular imaging applications.
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Affiliation(s)
- Dong Cui
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637457, Singapore
| | - Chen Xie
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637457, Singapore
| | - Kanyi Pu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637457, Singapore
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48
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Vadukul DM, Gbajumo O, Marshall KE, Serpell LC. Amyloidogenicity and toxicity of the reverse and scrambled variants of amyloid-β 1-42. FEBS Lett 2017; 591:822-830. [PMID: 28185264 PMCID: PMC5363225 DOI: 10.1002/1873-3468.12590] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/17/2017] [Accepted: 02/05/2017] [Indexed: 12/29/2022]
Abstract
β‐amyloid 1‐42 (Aβ1‐42) is a self‐assembling peptide that goes through many conformational and morphological changes before forming the fibrils that are deposited in extracellular plaques characteristic of Alzheimer's disease. The link between Aβ1‐42 structure and toxicity is of major interest, in particular, the neurotoxic potential of oligomeric species. Many studies utilise reversed (Aβ42‐1) and scrambled (AβS) forms of amyloid‐β as control peptides. Here, using circular dichroism, thioflavin T fluorescence and transmission electron microscopy, we reveal that both control peptides self‐assemble to form fibres within 24 h. However, oligomeric Aβ reduces cell survival of hippocampal neurons, while Aβ42‐1 and Aβs have reduced effect on cellular health, which may arise from their ability to assemble rapidly to form protofibrils and fibrils.
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49
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Moore KA, Pate KM, Soto-Ortega DD, Lohse S, van der Munnik N, Lim M, Jackson KS, Lyles VD, Jones L, Glassgow N, Napumecheno VM, Mobley S, Uline MJ, Mahtab R, Murphy CJ, Moss MA. Influence of gold nanoparticle surface chemistry and diameter upon Alzheimer's disease amyloid-β protein aggregation. J Biol Eng 2017; 11:5. [PMID: 28191036 PMCID: PMC5292815 DOI: 10.1186/s13036-017-0047-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 01/03/2017] [Indexed: 12/30/2022] Open
Abstract
Background Deposits of aggregated amyloid-β protein (Aβ) are a pathological hallmark of Alzheimer’s disease (AD). Thus, one therapeutic strategy is to eliminate these deposits by halting Aβ aggregation. While a variety of possible aggregation inhibitors have been explored, only nanoparticles (NPs) exhibit promise at low substoichiometric ratios. With tunable size, shape, and surface properties, NPs present an ideal platform for rationally designed Aβ aggregation inhibitors. In this study, we characterized the inhibitory capabilities of gold nanospheres exhibiting different surface coatings and diameters. Results Both NP diameter and surface chemistry were found to modulate the extent of aggregation, while NP electric charge influenced aggregate morphology. Notably, 8 nm and 18 nm poly(acrylic acid)-coated NPs abrogated Aβ aggregation at a substoichiometric ratio of 1:2,000,000. Theoretical calculations suggest that this low stoichiometry could arise from altered solution conditions near the NP surface. Specifically, local solution pH and charge density are congruent with conditions that influence aggregation. Conclusions These findings demonstrate the potential of surface-coated gold nanospheres to serve as tunable therapeutic agents for the inhibition of Aβ aggregation. Insights gained into the physiochemical properties of effective NP inhibitors will inform future rational design of effective NP-based therapeutics for AD. Electronic supplementary material The online version of this article (doi:10.1186/s13036-017-0047-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kelly A Moore
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208 USA
| | - Kayla M Pate
- Department of Chemical Engineering, University of South Carolina, 2C02 Swearingen Engineering Center, Columbia, SC 29208 USA
| | - Deborah D Soto-Ortega
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208 USA
| | - Samuel Lohse
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Nicholas van der Munnik
- Department of Chemical Engineering, University of South Carolina, 2C02 Swearingen Engineering Center, Columbia, SC 29208 USA
| | - Mihyun Lim
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208 USA
| | - Kaliah S Jackson
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Venetia D Lyles
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Lemeisha Jones
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Nisha Glassgow
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Vanessa M Napumecheno
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Shanee Mobley
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Mark J Uline
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208 USA.,Department of Chemical Engineering, University of South Carolina, 2C02 Swearingen Engineering Center, Columbia, SC 29208 USA
| | - Rahina Mahtab
- Department of Biological and Physical Sciences, South Carolina State University, Orangeburg, SC 29117 USA
| | - Catherine J Murphy
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Melissa A Moss
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208 USA.,Department of Chemical Engineering, University of South Carolina, 2C02 Swearingen Engineering Center, Columbia, SC 29208 USA
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50
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Miao Q, Pu K. Emerging Designs of Activatable Photoacoustic Probes for Molecular Imaging. Bioconjug Chem 2016; 27:2808-2823. [DOI: 10.1021/acs.bioconjchem.6b00641] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Qingqing Miao
- School of Chemical and Biomedical
Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore, 637457
| | - Kanyi Pu
- School of Chemical and Biomedical
Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore, 637457
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