1
|
Blomgren F, Rodin A, Chrobak W, Pacut DW, Swenson J, Ermilova I. Two statins and cromolyn as possible drugs against the cytotoxicity of Aβ(31-35) and Aβ(25-35) peptides: a comparative study by advanced computer simulation methods. RSC Adv 2022; 12:13352-13366. [PMID: 35520132 PMCID: PMC9066867 DOI: 10.1039/d2ra01963a] [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: 03/26/2022] [Accepted: 04/19/2022] [Indexed: 11/21/2022] Open
Abstract
In this work, possible effective mechanisms of cromolyn, atorvastatin and lovastatin on the cytotoxicity of Aβ(31-35) and Aβ(25-35) peptides were investigated by classical molecular dynamics and well-tempered metadynamics simulations. The results demonstrate that all the drugs affect the behavior of the peptides, such as their ability to aggregate, and alter their secondary structures and their affinity to a particular drug. Our findings from the computed properties suggest that the best drug candidate is lovastatin. This medicine inhibits peptide aggregation, adsorbs the peptides on the surface of the drug clusters, changes the secondary structure and binds to MET35, which has been seen as the reason for the toxicity of the studied peptide sequences. Moreover, lovastatin is the drug which previously has demonstrated the strongest ability to penetrate the blood-brain barrier and makes lovastatin the most promising medicine among the three investigated drugs. Atorvastatin is also seen as a potential candidate if its penetration through the blood-brain barrier could be improved. Otherwise, its properties are even better than the ones demonstrated by lovastatin. Cromolyn appears to be less interesting as an anti-aggregant from the computational data, in comparison to the two statins.
Collapse
Affiliation(s)
- Fredrik Blomgren
- Department of Physics, Chalmers University of Technology Fysikgränd 4 Göteborg 41258 Sweden +46-728487773
| | - Alexander Rodin
- Department of Physics, Chalmers University of Technology Fysikgränd 4 Göteborg 41258 Sweden +46-728487773
| | - Wojciech Chrobak
- Department of Physics, Chalmers University of Technology Fysikgränd 4 Göteborg 41258 Sweden +46-728487773
| | - Dawid Wojciech Pacut
- Department of Physics, Chalmers University of Technology Fysikgränd 4 Göteborg 41258 Sweden +46-728487773
| | - Jan Swenson
- Department of Physics, Chalmers University of Technology Fysikgränd 4 Göteborg 41258 Sweden +46-728487773
| | - Inna Ermilova
- Department of Physics, Chalmers University of Technology Fysikgränd 4 Göteborg 41258 Sweden +46-728487773
| |
Collapse
|
2
|
Leite JP, Lete MG, Fowler SB, Gimeno A, Rocha JF, Sousa SF, Webster CI, Jiménez-Bar̀bero JJ, Gales L. Aβ 31-35 Decreases Neprilysin-Mediated Alzheimer's Amyloid-β Peptide Degradation. ACS Chem Neurosci 2021; 12:3708-3718. [PMID: 34505762 DOI: 10.1021/acschemneuro.1c00432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Alzheimer's disease is associated with the deposition of extracellular senile plaques, made primarily of amyloid-β (Aβ), particularly peptides Aβ1-42 and Aβ1-40. Neprilysin, or neutral endopeptidase (NEP), catalyzes proteolysis of the amyloid peptides (Aβ) and is recognized as one of the major regulators of the levels of these peptides in the brain, preventing Aβ accumulation and plaque formation. Here, we used a combination of techniques to elucidate the mechanism of Aβ binding and cleavage by NEP. Our findings indicate that the Aβ31-X cleavage products remain bound to the neprilysin active site, reducing proteolytic activity. Interestingly, it was already shown that this Aβ31-35 sequence is also critical for recognition of Aβ peptides by other targets, such as the serpin-enzyme complex receptor in neuronal cells.
Collapse
Affiliation(s)
- José P. Leite
- i3S—Instituto de Investigação e Inovação em Saúde, Rua Alfredo Allen, 208, Porto 4200-135, Portugal
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, Porto 4200-135, Portugal
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Marta G. Lete
- CIC bioGUNE, Bizkaia Technology Park, Building 801A, Derio 48170, Spain
| | - Susan B. Fowler
- Antibody Discovery & Protein Engineering R&D, AstraZeneca, Cambridge CB21 6GH, U.K
| | - Ana Gimeno
- CIC bioGUNE, Bizkaia Technology Park, Building 801A, Derio 48170, Spain
| | - Juliana F. Rocha
- UCIBIO/REQUIMTE, BioSIM-Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, Porto 4200-319, Portugal
| | - Sérgio F. Sousa
- UCIBIO/REQUIMTE, BioSIM-Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, Porto 4200-319, Portugal
| | - Carl I. Webster
- Antibody Discovery & Protein Engineering R&D, AstraZeneca, Cambridge CB21 6GH, U.K
| | - Jesús J. Jiménez-Bar̀bero
- CIC bioGUNE, Bizkaia Technology Park, Building 801A, Derio 48170, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao 48013, Spain
- Department of Organic Chemistry II, Faculty of Science and Technology, UPV-EHU, 48940 Leioa, Spain
| | - Luís Gales
- i3S—Instituto de Investigação e Inovação em Saúde, Rua Alfredo Allen, 208, Porto 4200-135, Portugal
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, Porto 4200-135, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| |
Collapse
|
3
|
Chrobak W, Pacut DW, Blomgren F, Rodin A, Swenson J, Ermilova I. Component of Cannabis, Cannabidiol, as a Possible Drug against the Cytotoxicity of Aβ(31-35) and Aβ(25-35) Peptides: An Investigation by Molecular Dynamics and Well-Tempered Metadynamics Simulations. ACS Chem Neurosci 2021; 12:660-674. [PMID: 33544587 PMCID: PMC8023578 DOI: 10.1021/acschemneuro.0c00692] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/01/2021] [Indexed: 12/14/2022] Open
Abstract
In this work cannabidiol (CBD) was investigated as a possible drug against the cytotoxicity of Aβ(31-35) and Aβ(25-35) peptides with the help of atomistic molecular dynamics (MD) and well-tempered metadynamics simulations. Four interrelated mechanisms of possible actions of CBD are proposed from our computations. This implies that one mechanism can be a cause or/and a consequence of another. CBD is able to decrease the aggregation of peptides at certain concentrations of compounds in water. This particular action is more prominent for Aβ(25-35), since originally Aβ(31-35) did not exhibit aggregation properties in aqueous solutions. Interactions of CBD with the peptides affect secondary structures of the latter ones. Clusters of CBD are seen as possible adsorbents of Aβ(31-35) and Aβ(25-35) since peptides are tending to aggregate around them. And last but not least, CBD exhibits binding to MET35. All four mechanisms of actions can possibly inhibit the Aβ-cytotoxicity as discussed in this paper. Moreover, the amount of water also played a role in peptide clustering: with a growing concentration of peptides in water without a drug, the aggregation of both Aβ(31-35) and Aβ(25-35) increased. The number of hydrogen bonds between peptides and water was significantly higher for simulations with Aβ(25-35) at the higher concentration of peptides, while for Aβ(31-35) that difference was rather insignificant. The presence of CBD did not substantially affect the number of hydrogen bonds in the simulated systems.
Collapse
Affiliation(s)
| | | | | | | | - Jan Swenson
- Department of Physics, Chalmers
University of Technology, 412 96 Gothenburg, Sweden
| | - Inna Ermilova
- Department of Physics, Chalmers
University of Technology, 412 96 Gothenburg, Sweden
| |
Collapse
|
4
|
De novo aggregation of Alzheimer's Aβ25-35 peptides in a lipid bilayer. Sci Rep 2019; 9:7161. [PMID: 31073226 PMCID: PMC6509337 DOI: 10.1038/s41598-019-43685-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/27/2019] [Indexed: 11/28/2022] Open
Abstract
A potential mechanism of cytotoxicity attributed to Alzheimer’s Aβ peptides postulates that their aggregation disrupts membrane structure causing uncontrollable permeation of Ca2+ ions. To gain molecular insights into these processes, we have performed all-atom explicit solvent replica exchange with solute tempering molecular dynamics simulations probing aggregation of the naturally occurring Aβ fragment Aβ25-35 within the DMPC lipid bilayer. To compare the impact produced on the bilayer by Aβ25-35 oligomers and monomers, we used as a control our previous simulations, which explored binding of Aβ25-35 monomers to the same bilayer. We found that compared to monomeric species aggregation results in much deeper insertion of Aβ25-35 peptides into the bilayer hydrophobic core causing more pronounced disruption in its structure. Aβ25-35 peptides aggregate by incorporating monomer-like structures with stable C-terminal helix. As a result the Aβ25-35 dimer features unusual helix head-to-tail topology supported by a parallel off-registry interface. Such topology affords further growth of an aggregate by recruiting additional peptides. Free energy landscape reveals that inserted dimers represent the dominant equilibrium state augmented by two metastable states associated with surface bound dimers and inserted monomers. Using the free energy landscape we propose the pathway of Aβ25-35 binding, aggregation, and insertion into the lipid bilayer.
Collapse
|
5
|
Sambasivam D, Sivanesan S, Sultana S, Rajadas J. Conformational Preferences of Aβ25-35 and Aβ35-25 in Membrane Mimicking Environments. Protein Pept Lett 2019; 26:386-390. [PMID: 30836907 DOI: 10.2174/0929866526666190228122849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 01/03/2019] [Accepted: 02/04/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND The structural transition of aggregating Abeta peptides is the key event in the progression of Alzheimer's Disease (AD). OBJECTIVE In the present work, the structural modifications of toxic Aβ25-35 and the scrambled Aβ35-25 were studied in Trifluoroethanol (TFE) and in aqueous SDS micelles. METHODS Using CD spectroscopic investigations, the conformational transition of Aβ25-35 and Aβ35-25 peptides were determined in different membrane mimicking environments such as TFE and SDS. An interval scan CD of the peptides on evaporation of TFE was performed. TFE titrations were carried out to investigate the intrinsic ability of the structural conformations of peptides. RESULTS We show by spectroscopic evidence that Aβ25-35 prefers beta sheet structures upon increasing TFE concentrations. On the other hand, the non-toxic scrambled Aβ35-25 peptide only undergoes a transition from random coil to α-helix conformation with increasing TFE. In the interval scan studies, Aβ25-35 did not show any structural transitions, whereas Aβ35-25 showed transition from α-helix to β-sheet conformation. In membrane simulating aqueous SDS micelles, Aβ25-35 showed a transition from random coil to α-helix while Aβ35-25 underwent transition from random coil to β-sheet conformation. CONCLUSION Overall, the current results seek new insights into the structural properties of amyloidogenic and the truncated sequence in membrane mimicking solvents.
Collapse
Affiliation(s)
- Dhandayuthapani Sambasivam
- Bioorganic Chemistry Laboratory, Central Leather Research Institute, Adyar, Chennai 600 020, India.,Department of Chemistry, St Peter's Institute of Higher Education and Research, Chennai-600054, India
| | - Senthilkumar Sivanesan
- Bioorganic Chemistry Laboratory, Central Leather Research Institute, Adyar, Chennai 600 020, India
| | - Sayeeda Sultana
- Department of Chemistry, St Peter's Institute of Higher Education and Research, Chennai-600054, India
| | - Jayakumar Rajadas
- Bioorganic Chemistry Laboratory, Central Leather Research Institute, Adyar, Chennai 600 020, India.,Biomaterials and Advanced Drug Delivery Laboratory (BioADD), Stanford University School of Medicine, Stanford, CA, United States
| |
Collapse
|
6
|
Smith AK, Klimov DK. Binding of Cytotoxic Aβ25–35 Peptide to the Dimyristoylphosphatidylcholine Lipid Bilayer. J Chem Inf Model 2018; 58:1053-1065. [DOI: 10.1021/acs.jcim.8b00045] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Amy K. Smith
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
| | - Dmitri K. Klimov
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
| |
Collapse
|
7
|
Functional modulation of strychnine-sensitive glycine receptors in rat hippocampal pyramidal neurons by amyloid-β protein (1-42). Brain Res 2016; 1651:61-72. [DOI: 10.1016/j.brainres.2016.09.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 09/07/2016] [Accepted: 09/09/2016] [Indexed: 11/17/2022]
|
8
|
Ferdousi M, Habibi-Rezaei M, Balalaie S, Ramezanpour S, Sabouni F, Poursasan N, Sabokdast M, Moosavi-Movahedi AA. Toxicity of serum albumin on microglia upon seeding effect of amyloid peptide. J Biochem 2016; 160:325-332. [PMID: 27405917 DOI: 10.1093/jb/mvw042] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Accepted: 05/31/2016] [Indexed: 12/14/2022] Open
Abstract
We demonstrate in vitro cross-seeding of bovine serum albumin (BSA) in the presence of Aβ25-35 and their cytotoxic effects on microglial cells. To investigate the cross-seeding of BSA in the presence of Aβ25-35 fibrils, we examined how Aβ25-35 fibrils can function as seeds to trigger and accelerate BSA fibrillogenesis using ThT, intrinsic fluorescence, ANS fluorescence and transmission electron microscopy (TEM). Moreover, the effects of these fibrils on microglial viability were measured using MTT and Annexin V/propidium iodide (PI) staining. Although Aβ25-35 is toxic against microglia, it acted as seed and affected the aggregation pathway and accelerated the fibrillogenesis of BSA in vitro, resulted in an enhanced cytotoxic effect in comparison with Aβ25-35 or BSA alone. These observations thought to be helpful to understand the molecular mechanism of enhanced toxicity due to the coexistence of the aggregation prone proteins/peptides,. then cross-seeding effect on microglial cells that may involve in neurodegenerative diseases such as Alzheimer's disease (AD).
Collapse
Affiliation(s)
- Maryam Ferdousi
- School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Mehran Habibi-Rezaei
- School of Biology, College of Science, University of Tehran, Tehran, Iran .,Nano-Biomedicine Center of Excellence, Nanoscience and Nanotechnology Research Center, University of Tehran, Tehran, Iran
| | - Saeed Balalaie
- Peptide Chemistry Research Center, K. N. Toosi University of Technology, Tehran, Iran
| | - Sorour Ramezanpour
- Peptide Chemistry Research Center, K. N. Toosi University of Technology, Tehran, Iran
| | - Farzaneh Sabouni
- Department of Basic Sciences of Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Najmeh Poursasan
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Manijheh Sabokdast
- School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Ali A Moosavi-Movahedi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.,Center of Excellence in Biothermodynamics, University of Tehran, Tehran, Iran
| |
Collapse
|
9
|
Yuan L, Liu XJ, Han WN, Li QS, Wang ZJ, Wu MN, Yang W, Qi JS. [Gly14]-Humanin Protects Against Amyloid β Peptide-Induced Impairment of Spatial Learning and Memory in Rats. Neurosci Bull 2016; 32:374-82. [PMID: 27306655 DOI: 10.1007/s12264-016-0041-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 05/11/2016] [Indexed: 01/03/2023] Open
Abstract
Alzheimer disease (AD), a progressive neurodegenerative disorder, is characterized by cognitive decline and the accumulation of senile plaques in the brain. Amyloid β protein (Aβ) in the plaques is thought to be responsible for the memory loss in AD patients. [Gly14]-humanin (HNG), a derivative of humanin (HN), has much stronger neuroprotective effects than natural HN in vitro. However, clarification of the Aβ active center and the neuroprotective mechanism of HN still need in vivo evidence. The present study first compared the in vivo biological effects of three Aβ fragments (1-42, 31-35, and 35-31) on spatial memory in rats, and investigated the neuroprotective effects and molecular mechanisms of HNG. The results showed that intrahippocampal injection of Aβ1-42 and Aβ31-35 almost equally impaired spatial learning and memory, but the reversed sequence Aβ35-31 did not have any effect; a high dose of Aβ31-35 (20 nmol) produced a more detrimental response than a low dose (2 nmol); Aβ31-35 injection also disrupted gene and protein expression in the hippocampus, with up-regulation of caspase3 and down-regulation of STAT3; pretreatment with HNG not only protected spatial memory but also rescued STAT3 from Aβ-induced disruption; and the neuroprotective effects of HNG were effectively counteracted by genistein, a specific tyrosine kinase inhibitor. These results clearly show that sequence 31-35 in Aβ is the shortest active center responsible for the neurotoxicity of Aβ from molecule to behavior; and HNG protects spatial learning and memory in rats against Aβ-induced insults; and probably involves the activation of tyrosine kinases and subsequent beneficial modulation of STAT3 and caspase3.
Collapse
Affiliation(s)
- Li Yuan
- Department of Physiology, Shanxi Medical University, Taiyuan, 030001, China
| | - Xiao-Jie Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Wei-Na Han
- Department of Physiology, Shaoyang Medical College, Shaoyang, 422000, China
| | - Qing-Shan Li
- Department of Physiology, Shanxi Medical University, Taiyuan, 030001, China
| | - Zhao-Jun Wang
- Department of Physiology, Shanxi Medical University, Taiyuan, 030001, China
| | - Mei-Na Wu
- Department of Physiology, Shanxi Medical University, Taiyuan, 030001, China
| | - Wei Yang
- Department of Physiology, Shanxi Medical University, Taiyuan, 030001, China
| | - Jin-Shun Qi
- Department of Physiology, Shanxi Medical University, Taiyuan, 030001, China.
| |
Collapse
|
10
|
Gu M, Viles JH. Methionine oxidation reduces lag-times for amyloid-β(1-40) fiber formation but generates highly fragmented fibers. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:1260-1269. [PMID: 27108954 DOI: 10.1016/j.bbapap.2016.04.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/19/2016] [Indexed: 01/06/2023]
Abstract
Oxidative stress and the formation of amyloid plaques containing amyloid-β (Aβ) peptides are two key hallmarks of Alzheimer's disease. A proportion of methionine (Met) at position 35 within Aβ is oxidized to methionine sulphoxide (Met(OX)) within the Alzheimer's plaques. These oxidative processes may be the key to understanding the early stages of Alzheimer's disease. In vitro oxidation of Aβ, by the physiological oxidant H2O2, was monitored using (1)H NMR and mass spectrometry. Here we investigate the effect of Aβ methionine oxidation on fiber formation kinetics and morphology using the amyloid specific fluorescence dye Thioflavin T (ThT) and Transmission Electron Microscopy (TEM). Methionine oxidation reduces the total amount of fibers generated for both dominant forms of Aβ, however there are marked differences in the effect of Met(OX) between Aβ(1-40) and Aβ(1-42). Surprisingly the presence of Met(OX) reduces lag-times for Aβ(1-40) fiber formation but extends lag-times for Aβ(1-42). TEM indicates a change in fiber morphology with a pronounced reduction in fiber length for both methionine oxidized Aβ(1-40) and Aβ(1-42). In contrast, the morphology of preformed amyloid fibers is largely unaffected by the presence of H2O2. Our studies suggest that methionine oxidation promotes highly fragmented fiber assemblies of Aβ. Oxidative stress associated with Alzheimer's disease can cause oxidation of methionine within Aβ and this in turn will influence the complex assembly of Aβ monomer into amyloid fibers, which is likely to impact Aβ toxicity.
Collapse
Affiliation(s)
- Miao Gu
- School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
| | - John H Viles
- School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
| |
Collapse
|
11
|
Kim H, Youn K, Yun EY, Hwang JS, Jeong WS, Ho CT, Jun M. Oleic acid ameliorates Aβ-induced inflammation by downregulation of COX-2 and iNOS via NFκB signaling pathway. J Funct Foods 2015. [DOI: 10.1016/j.jff.2015.01.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
|
12
|
Tsai HHG, Lee JB, Shih YC, Wan L, Shieh FK, Chen CY. Location and Conformation of Amyloid β(25-35) Peptide and its Sequence-Shuffled Peptides within Membranes: Implications for Aggregation and Toxicity in PC12 Cells. ChemMedChem 2014; 9:1002-11. [DOI: 10.1002/cmdc.201400062] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Indexed: 12/18/2022]
|
13
|
Bao X, Jin Y, Liu X, Liao H, Zhang L, Pang T. Synthesis and biological evaluation of XB-1 analogues as novel histamine H3 receptor antagonists and neuroprotective agents. RSC Adv 2014. [DOI: 10.1039/c3ra46392c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
|
14
|
Wang ZJ, Han WN, Yang GZ, Yuan L, Liu XJ, Li QS, Qi JS. The neuroprotection of Rattin against amyloid β peptide in spatial memory and synaptic plasticity of rats. Hippocampus 2013; 24:44-53. [PMID: 23996574 DOI: 10.1002/hipo.22202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 12/22/2022]
Abstract
Rattin, a specific derivative of humanin in rats, shares the ability with HN to protect neurons against amyloid β (Aβ) peptide-induced cellular toxicity. However, it is still unclear whether Rattin can protect against Aβ-induced deficits in cognition and synaptic plasticity in rats. In the present study, we observed the effects of Rattin and Aβ31-35 on the spatial reference memory and in vivo hippocampal Long-term potentiation of rats by using Morris water maze test and hippocampal field potential recording. Furthermore, the probable molecular mechanism underlying the neuroprotective roles of Rattin was investigated. We showed that intra-hippocampal injection of Rattin effectively prevented the Aβ31-35-induced spatial memory deficits and hippocampal LTP suppression in rats; the Aβ31-35-induced activation of Caspase-3 and inhibition of STAT3 in the hippocampus were also prevented by Rattin treatment. These findings indicate that Rattin treatment can protect spatial memory and synaptic plasticity of rats against Aβ31-35-induced impairments, and the underlying protective mechanism of Rattin may be involved in STAT3 and Caspases-3 pathways. Therefore, application of Rattin or activation of its signaling pathways in the brain might be beneficial to the prevention of Aβ-related cognitive deficits.
Collapse
Affiliation(s)
- Zhao-Jun Wang
- Department of Neurobiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
15
|
Yates EA, Owens SL, Lynch MF, Cucco EM, Umbaugh CS, Legleiter J. Specific domains of Aβ facilitate aggregation on and association with lipid bilayers. J Mol Biol 2013; 425:1915-1933. [PMID: 23524134 DOI: 10.1016/j.jmb.2013.03.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 02/09/2013] [Accepted: 03/04/2013] [Indexed: 11/27/2022]
Abstract
A hallmark of Alzheimer's disease, a late-onset neurodegenerative disease, is the deposition of neuritic amyloid plaques composed of aggregated forms of the β-amyloid peptide (Aβ). Aβ forms a variety of nanoscale, toxic aggregate species ranging from small oligomers to fibrils. Aβ and many of its aggregate forms strongly interact with lipid membranes, which may represent an important step in several toxic mechanisms. Understanding the role that specific regions of Aβ play in regulating its aggregation and interaction with lipid membranes may provide insights into the fundamental interaction between Aβ and cellular surfaces. We investigated the interaction and aggregation of several Aβ fragments (Aβ1-11, Aβ1-28, Aβ10-26, Aβ12-24, Aβ16-22, Aβ22-35, and Aβ1-40) in the presence of supported model total brain lipid extract (TBLE) bilayers. These fragments represent a variety of chemically unique domains within Aβ, that is, the extracellular domain, the central hydrophobic core, and the transmembrane domain. Using scanning probe techniques, we elucidated aggregate morphologies for these different Aβ fragments in free solution and in the presence of TBLE bilayers. These fragments formed a variety of oligomeric and fibrillar aggregates under free solution conditions. Exposure to TBLE bilayers resulted in distinct aggregate morphologies compared to free solution and changes in bilayer stability dependent on the Aβ sequence. Aβ10-26, Aβ16-22, Aβ22-35, and Aβ1-40 aggregated into a variety of distinct fibrillar aggregates and disrupted the bilayer structure, resulting in altered mechanical properties of the bilayer. Aβ1-11, Aβ1-28, and Aβ12-24 had minimal interaction with lipid membranes, forming only sparse oligomers.
Collapse
Affiliation(s)
- Elizabeth A Yates
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University, Morgantown, WV 26506, USA
| | - Sherry L Owens
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University, Morgantown, WV 26506, USA
| | - Michael F Lynch
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University, Morgantown, WV 26506, USA
| | - Elena M Cucco
- Center for Neuroscience, Robert C. Byrd Health Sciences Center, PO Box 9304, West Virginia University, Morgantown, WV 26506, USA
| | - C Samuel Umbaugh
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University, Morgantown, WV 26506, USA
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University, Morgantown, WV 26506, USA; Center for Neuroscience, Robert C. Byrd Health Sciences Center, PO Box 9304, West Virginia University, Morgantown, WV 26506, USA; NanoSAFE, PO Box 6223, West Virginia University, Morgantown, WV 26506, USA.
| |
Collapse
|
16
|
Role of β-hairpin formation in aggregation: the self-assembly of the amyloid-β(25-35) peptide. Biophys J 2013; 103:576-586. [PMID: 22947874 DOI: 10.1016/j.bpj.2012.06.027] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 06/12/2012] [Accepted: 06/14/2012] [Indexed: 12/28/2022] Open
Abstract
The amyloid-β(25-35) peptide plays a key role in the etiology of Alzheimer's disease due to its extreme toxicity even in the absence of aging. Because of its high tendency to aggregate and its low solubility in water, the structure of this peptide is still unknown. In this work, we sought to understand the early stages of aggregation of the amyloid-β(25-35) peptide by conducting simulations of oligomers ranging from monomers to tetramers. Our simulations show that although the monomer preferentially adopts a β-hairpin conformation, larger aggregates have extended structures, and a clear transition from compact β-hairpin conformations to extended β-strand structures occurs between dimers and trimers. Even though β-hairpins are not present in the final architecture of the fibril, our simulations indicate that they play a critical role in fibril growth. Our simulations also show that β-sheet structures are stabilized when a β-hairpin is present at the edge of the sheet. The binding of the hairpin to the sheet leads to a subsequent destabilization of the hairpin, with part of the hairpin backbone dangling in solution. This free section of the peptide can then recruit an extra monomer from solution, leading to further sheet extension. Our simulations indicate that the peptide must possess sufficient conformational flexibility to switch between a hairpin and an extended conformation in order for β-sheet extension to occur, and offer a rationalization for the experimental observation that overstabilizing a hairpin conformation in the monomeric state (for example, through chemical cross-linking) significantly hampers the fibrillization process.
Collapse
|
17
|
He YX, Wu MN, Zhang H, Qi JS. Amyloid β-protein suppressed nicotinic acetylcholine receptor-mediated currents in acutely isolated rat hippocampal CA1 pyramidal neurons. Synapse 2012; 67:11-20. [PMID: 23015319 DOI: 10.1002/syn.21611] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 09/14/2012] [Indexed: 11/10/2022]
Abstract
Amyloid β protein (Aβ) is responsible for the deficits of learning and memory in Alzheimer's disease (AD). The high affinity between Aβ and nicotinic acetylcholine receptors (nAChRs) suggests that the impairment of cognitive function in AD might be involved in the Aβ-induced damage of nAChRs. This study investigated the effects of Aβ fragments on nAChR-mediated membrane currents in acutely isolated rat hippocampal pyramidal neurons by using whole-cell patch clamp technique. The results showed that: (1) nonspecific nAChR agonist nicotine, selective α7 nAChR agonist choline, and α4β2 nAChR agonist epibatidine all effectively evoked inward currents in CA1 neurons at normal resting membrane potential, with different desensitization characteristics; (2) acute application of different concentrations (pM-μM) of Aβ25-35, Aβ31-35, or Aβ35-31 alone did not trigger any membrane current, but pretreatment with 1 μM Aβ25-35 and Aβ31-35 similarly and reversibly suppressed the nicotine-induced currents; (3) further, choline- and epibatidine-induced currents were also reversibly suppressed by the Aβ pretreatment, but more prominent for the choline-induced response. These results demonstrate that the functional activity of both α7 and α4β2 nAChRs in the membrane of acutely isolated hippocampal neurons was significantly downregulated by Aβ treatment, suggesting that nAChRs, especially α7 nAChRs, in the brain may be the important biological targets of neurotoxic Aβ in AD. In addition, the similar suppression of nAChR currents by Aβ25-35 and Aβ31-35 suggests that the sequence 31-35 in Aβ molecule may be a shorter active center responsible for the neurotoxicity of Aβ in AD.
Collapse
Affiliation(s)
- Ye-Xin He
- Department of Radiology, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, People's Republic of China
| | | | | | | |
Collapse
|
18
|
Shimizu K, Takahama S, Endo Y, Sawasaki T. Stress-inducible caspase substrate TRB3 promotes nuclear translocation of procaspase-3. PLoS One 2012; 7:e42721. [PMID: 22912727 PMCID: PMC3415431 DOI: 10.1371/journal.pone.0042721] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/10/2012] [Indexed: 11/18/2022] Open
Abstract
Pseudokinase TRB3 is a stress-inducible nuclear protein, which has recently been shown to be involved in ER stress-induced apoptosis. However, it remains unclear how TRB3 contributes to the process. We recently demonstrated that TRB3 was cleaved by caspase-3 (CASP3) in vitro and also in apoptosis-induced cells. Thus, we investigate the role of TRB3 cleavage in the apoptotic process to address the above question. Overexpression studies revealed that the cleavage of TRB3 promoted CASP3/7 activation and apoptosis. In contrast, the anti-apoptotic effects were found under TRB3 non-cleavable conditions, such as ER stress, and also when the CASP3/7 activation was enhanced by knockdown of endogenous TRB3 expression. Interestingly, nuclear translocation of procaspase-3 (proCASP3) was observed in cells either overexpressing TRB3 or under tunicamycin-induced ER stress. Although forced cytoplasmic expression of proCASP3 enhanced apoptosis significantly, its nuclear expression did not produce any pro-apoptotic effect, suggesting that nuclear distribution of proCASP3 is not critical for the execution of apoptosis. Thus, TRB3 might prevent cytoplasmic activation of CASP3 by promoting proCASP3 entry into the nucleus, and thereby inhibit apoptosis. Taken together, our results suggest that TRB3, through its own cleavage, functions as a molecular switch between the cell survival and apoptotic pathways under stressful conditions.
Collapse
Affiliation(s)
- Kouhei Shimizu
- The Cell-Free Science and Technology Research Center, Ehime University, Matsuyama, Japan
| | | | - Yaeta Endo
- The Cell-Free Science and Technology Research Center, Ehime University, Matsuyama, Japan
- The Venture Business Laboratory, Ehime University, Matsuyama, Japan
- Proteo-Medicine Research Center, Ehime University, Toon, Japan
- RIKEN Systems and Structural Biology Center, Yokohama, Japan
| | - Tatsuya Sawasaki
- The Cell-Free Science and Technology Research Center, Ehime University, Matsuyama, Japan
- The Venture Business Laboratory, Ehime University, Matsuyama, Japan
- Proteo-Medicine Research Center, Ehime University, Toon, Japan
- RIKEN Systems and Structural Biology Center, Yokohama, Japan
- * E-mail:
| |
Collapse
|
19
|
Deletion of microsomal prostaglandin E synthase-1 protects neuronal cells from cytotoxic effects of β-amyloid peptide fragment 31–35. Biochem Biophys Res Commun 2012; 424:409-13. [DOI: 10.1016/j.bbrc.2012.06.121] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 06/24/2012] [Indexed: 02/04/2023]
|
20
|
Zhi-Kun S, Hong-Qi Y, Zhi-Quan W, Jing P, Zhen H, Sheng-Di C. Erythropoietin prevents PC12 cells from beta-amyloid-induced apoptosis via PI3K⁄Akt pathway. Transl Neurodegener 2012; 1:7. [PMID: 23211059 PMCID: PMC3514084 DOI: 10.1186/2047-9158-1-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 02/29/2012] [Indexed: 12/04/2022] Open
Abstract
Background Several studies indicated that Erythropoietin (Epo) may provide remarkable neuroprotection in some neurological diseases. It also showed the significant decrease of Epo immunoreactivity in the cerebral cortex and hippocampus in aged rats, suggesting the role of Epo in the pathogenesis of age-related neurodegenerative diseases such as AD. Methods The protective effect of Epo was studied in differentiated PC12 cells treated with Abeta. The viability of the cells, the apoptosis of the cells and the level of Bax, Bcl-2, cleaved caspase-3 and cleaved PARP expression were detected by MTT, Hoechst 33258 staining and Western blotting respectively. Results 20 μM Abeta (25-35) could induce a decreased viability and a increased apoptosis in PC12 cell in a time-dependent manner. However, 20 μM Abeta (35-25) had no effect on cell viability and apoptosis. Western blot analysis also showed that Abeta(25-35) treatment could decrease the expression of Bcl-2 (P < 0.05) and increase the expression of Bax (P < 0.05), Cleaved casapase-3 (P < 0.05), and Cleaved PARP (P < 0.05). The pretreatment of Epo could effectively reverse all the above changes induced by Abeta(25-35) (P < 0.05). Furthermore, the protective effect of Epo could be blocked by PI3K inhibitor LY294002 (P < 0.05). Conclusions Epo prevented cell injuries in PC12 cells exposed to the Abeta(25-35) and this effect may depend on the PI3K⁄Akt pathway. Our study provided an important evidence for the potential application of Epo in the therapy of Alzheimer's disease.
Collapse
Affiliation(s)
- Sun Zhi-Kun
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, People's Republic of China.
| | | | | | | | | | | |
Collapse
|
21
|
Grasso G, Giuffrida ML, Rizzarelli E. Metallostasis and amyloid β-degrading enzymes. Metallomics 2012; 4:937-49. [DOI: 10.1039/c2mt20105d] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
22
|
Aβ-degrading enzymes: potential for treatment of Alzheimer disease. J Neuropathol Exp Neurol 2011; 70:944-59. [PMID: 22002425 DOI: 10.1097/nen.0b013e3182345e46] [Citation(s) in RCA: 190] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
There is increasing evidence that deficient clearance of β-amyloid (Aβ) contributes to its accumulation in late-onset Alzheimer disease (AD). Several Aβ-degrading enzymes, including neprilysin (NEP), insulin-degrading enzyme, and endothelin-converting enzyme reduce Aβ levels and protect against cognitive impairment in mouse models of AD. The activity of several Aβ-degrading enzymes rises with age and increases still further in AD, perhaps as a physiological response to minimize the buildup of Aβ. The age- and disease-related changes in expression of more recently recognized Aβ-degrading enzymes (e.g. NEP-2 and cathepsin B) remain to be investigated, and there is strong evidence that reduced NEP activity contributes to the development of cerebral amyloid angiopathy. Regardless of the role of Aβ-degrading enzymes in the development of AD, experimental data indicate that increasing the activity of these enzymes (NEP in particular) has therapeutic potential in AD, although targeting their delivery to the brain remains a major challenge. The most promising current approaches include the peripheral administration of agents that enhance the activity of Aβ-degrading enzymes and the direct intracerebral delivery of NEP by convection-enhanced delivery. In the longer term, genetic approaches to increasing the intracerebral expression of NEP or other Aβ-degrading enzymes may offer advantages.
Collapse
|
23
|
Tsai HHG, Lee JB, Tseng SS, Pan XA, Shih YC. Folding and membrane insertion of amyloid-beta (25-35) peptide and its mutants: Implications for aggregation and neurotoxicity. Proteins 2010; 78:1909-25. [DOI: 10.1002/prot.22705] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
24
|
Guo F, Jing W, Ma CG, Wu MN, Zhang JF, Li XY, Qi JS. [Gly(14)]-humanin rescues long-term potentiation from amyloid beta protein-induced impairment in the rat hippocampal CA1 region in vivo. Synapse 2010; 64:83-91. [PMID: 19768812 DOI: 10.1002/syn.20707] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The novel neuroprotective action of Humanin (HN), especially its derivative [Gly(14)]-humanin (HNG), against Alzheimer's disease (AD)-related insults has been reported. However, it is still short of electrophysiological evidence for the protection of HN on synaptic plasticity, and the molecular mechanisms that underlie the neuroprotective function of HN remain largely unknown. The present study examined the effects of intracerebroventricular (i.c.v.) injection of HNG on amyloid beta (Abeta), a main constituent of senile plaques in the AD brain, induced suppression of long-term potentiation (LTP) in the rat hippocampal CA1 region in vivo and investigated the possible mechanism of HNG in LTP protection. We found that application of Abeta fragments 25-35 (Abeta25-35) and 31-35 (Abeta31-35) significantly inhibited high frequency stimulation-induced LTP, while HNG effectively prevented the suppression of LTP induced by Abeta fragments in a dose-dependent manner. After pretreatment with Genistein, a tyrosine kinase inhibitor, the protective action of HNG on LTP was nearly completely abolished. Therefore, the present study demonstrated for the first time that HNG could protect against the neurotoxic Abeta-induced hippocampal LTP impairment and the tyrosine kinase pathway was involved in the neuroprotective action of HNG, suggesting that HNG might be one of the promising candidates for the treatment of AD in the future.
Collapse
Affiliation(s)
- Fen Guo
- Department of Neurobiology, Key Laboratory for Cellular Physiology of Ministry of Education, Shanxi Medical University, Taiyuan 030001, China
| | | | | | | | | | | | | |
Collapse
|
25
|
Zhou Y, Liang M, Li W, Li K, Li P, Hu Y, Yang Z. Protective effects of Eucommia ulmoides Oliv. bark and leaf on amyloid β-induced cytotoxicity. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2009; 28:342-349. [PMID: 21784025 DOI: 10.1016/j.etap.2009.05.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 05/20/2009] [Accepted: 05/24/2009] [Indexed: 05/31/2023]
Abstract
The objectives of this study were to investigate the protective effects of Eucommia ulmoides Oliv. (EUO) bark and leaf against cytotoxicity induced by amyloid-β peptide (Aβ) and to explore their active components. The PC-12 cells injury mediated by Aβ(25-35) was employed to assess the neuroprotective effects of EUO bark, EUO leaf and various compounds. Intracellular Ca(2+) determination, MTT reduction assay, lactate dehydrogenase leakage evaluation and HO33258/PI staining were used to quantitatively or qualitatively evaluate cell viability and injury. The organic solvents partition and the macroporous resin separation were also applied to tracing the active constituents of EUO bark. Moreover, the effects of 8 compounds (3 iridoid glucoside, 3 phenylpripanoids and 2 flavonoids) were tested to identify the active compounds of EUO leaf. The results demonstrated that the water extracts of EUO barks and leaves, geniposidic acid and chlorogenic acid could efficiently protect PC-12 cells against the cytotoxicity of Aβ(25-35). This research suggests that EUO may represent a potential treatment strategy for Alzheimer's disease. Meanwhile, geniposidic acid and chlorogenic acid are the major active constituents of EUO barks and leaves, respectively.
Collapse
Affiliation(s)
- Yongqiang Zhou
- Key Laboratory of Modern Chinese Medicines, China Pharmaceutical University, Ministry of Education, Nanjing 210009, PR China
| | | | | | | | | | | | | |
Collapse
|
26
|
Abstract
The highly toxic A beta (25-35) is a peculiar peptide that differs from all the other commonly studied beta-amyloid peptides because of its extremely rapid aggregation properties and enhanced neurotoxicity. We investigated A beta (25-35) aggregation in H2O at pH 3.0 and at pH 7.4 by means of in-solution analyses. Adopting UV spectroscopy, Congo red spectrophotometry and thioflavin T fluorimetry, we were able to quantify, in water, the very fast assembling time necessary for A beta (25-35) to form stable insoluble aggregates and their ability to seed or not seed fibril growth. Our quantitative results, which confirm a very rapid assembly leading to stable insoluble aggregates of A beta (25-35) only when incubated at pH 7.4, might be helpful for designing novel aggregation inhibitors and to shed light on the in vivo environment in which fibril formation takes place.
Collapse
|
27
|
Neuroprotective effects of genistein and folic acid on apoptosis of rat cultured cortical neurons induced by β-amyloid 31-35. Br J Nutr 2009; 102:655-62. [DOI: 10.1017/s0007114509243042] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Genistein and folic acid have been reported respectively to protect against the development of cognitive dysfunction; however, the underlying mechanism(s) for this protection remain unknown. In this report, the mechanism(s) contributing to the neuroprotective effects of genistein and folic acid were explored using rat cortical neuron cultures. We found that genistein and folic acid, both separately and collaboratively, increased cell viability and mitochondrial membrane potential in β-amyloid (Aβ) 31-35-treated neurons. Furthermore, reduced percentage of comet cells and shortened tail length were observed in the neurons treated with genistein or folic acid. A more significant reduction in tail length of the comet neurons was observed in the co-administered neurons. RT-PCR analysis of the cultured cortical neurons showed down-regulated expression of p53, bax and caspase-3, but up-regulated expression of bcl-2 in the three neuroprotective treatment groups compared with neurons from the Aβ31-35 solo-treated group. In a nuclear dyeing experiment using Hoechst 33342, we found that both genistein and folic acid prevent neuronal apoptosis. Collectively, these findings suggest that the mechanism underlying the neuroprotection of genistein and folic acid singly or in combination observed in cultured cortical neuron studies might be related to their anti-apoptotic properties.
Collapse
|
28
|
Zhou YQ, Yang ZL, Xu L, Li P, Hu YZ. Akebia saponin D, a saponin component from Dipsacus asper Wall, protects PC 12 cells against amyloid-beta induced cytotoxicity. Cell Biol Int 2009; 33:1102-10. [PMID: 19615455 DOI: 10.1016/j.cellbi.2009.06.028] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 05/20/2009] [Accepted: 06/27/2009] [Indexed: 10/20/2022]
Abstract
According to Traditional Chinese Medicine, Alzheimer's disease (AD) is regarded as senile dementia, and the etiopathogenesis lies in kidney deficiency during aging. Dipsacus asper Wall (DAW), a well-known traditional Chinese medicine for enhancing kidney activity, may possess the therapeutic effects against AD. Our objectives were to investigate the protective effects of DAW against the amyloid-beta peptide (A beta)-induced cytotoxicity and explore its major active components. Injury of PC 12 cells mediated by A beta(25-35) was adopted to assess the cytoprotective effects of DAW aqueous extract and various fractions. Salvianolic acid B, a polyphenol compound isolated from Salvia miltiorrhiza, was employed as a positive control agent due to its markedly protective effect against neurotoxicity of amyloid beta. Five chemical fractions (i.e. alkaloids, essential oil, saponins, iridoid glucoside and polysaccharides) were prepared for activity test and analyzed by HPLC for active components identification. In addition, Akebia saponin D (the most important compound in DAW saponins) and hederagenin (the mother nucleus of akebia saponin D) were prepared for testing of their activity. DAW water extract, saponins fraction and akebia saponin D had the neuroprotective capacity to antagonize A beta(25-35)-induced cytotoxicity in PC 12 cells. In contrast, other fractions and hederagenin had no cytoprotective action. This research suggests that DAW may represent a potential treatment strategy for AD and akebia saponin D is one of its active components.
Collapse
Affiliation(s)
- Yong-Qiang Zhou
- Key Laboratory of Modern Chinese Medicines, China Pharmaceutical University, Ministry of Education, Nanjing 210009, PR China
| | | | | | | | | |
Collapse
|
29
|
Zhao L, Zhao ST, Qian ZM, Zhang C, Wu XM, Du F, Ke Y. Activation of group III metabotropic glutamate receptor reduces intracellular calcium in beta-amyloid peptide [31-35]-treated cortical neurons. Neurotox Res 2009; 16:174-83. [PMID: 19526293 DOI: 10.1007/s12640-009-9068-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 12/06/2008] [Accepted: 05/18/2009] [Indexed: 11/25/2022]
Abstract
It is unknown whether amyloid beta-protein 31-35 (Abeta[31-35]) has effects similar to Abeta[1-40] and Abeta[25-35] on the intracellular calcium ([Ca(2+)]i) to induce a disruption of calcium homeostasis. In this study, we investigated the effects of Abeta[31-35] on [Ca(2+)]i in primary cultured cortical neurons using real time fluorescence imaging technique and the Ca(2+)-sensitive dye Furo-2/AM. It was found that Abeta[31-35] (25 microM) could induce a significant elevation in [Ca(2+)]i and a decrease in the average latency in the cortical neurons in a dose-dependent manner. To examine whether the activation of group III mGluRs could block the changes in [Ca(2+)]i and protect neurons from apoptosis induced by Abeta[31-35], we then investigated the effects of L: -serine-O-phosphate (L: -SOP) and (R,S)-4-phosphonophenylglycine ((R,S)-PPG), the selective agonists of group III metabotropic glutamate receptors (mGluRs), on [Ca(2+)]i and apoptosis in neurons treated by Abeta[31-35]. We demonstrated that L: -SOP or (R,S)-PPG (100 microM) treatment suppresses significantly the elevation of [Ca(2+)]i induced by Abeta[31-35] and also induces an almost complete recovery of both the fluorescence intensity and apoptotic cells (%) to the control level in the neurons. These results suggest that Abeta[31-35] may be the shortest sequence responsible for the neuronal toxicity of Abeta protein and that the neuroprotective role of the activation of group III mGluRs from the apoptosis induced by Abeta[31-35] might be partly due to its ability to inhibit the increased calcium influx, which results from Abeta[31-35].
Collapse
Affiliation(s)
- Li Zhao
- Department of Neurobiology, Shanxi Medical University, 030001, Taiyuan, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
30
|
Piacentini R, Ripoli C, Leone L, Misiti F, Clementi ME, D'Ascenzo M, Giardina B, Azzena GB, Grassi C. Role of methionine 35 in the intracellular Ca2+ homeostasis dysregulation and Ca2+-dependent apoptosis induced by amyloid beta-peptide in human neuroblastoma IMR32 cells. J Neurochem 2009; 107:1070-82. [PMID: 18990116 DOI: 10.1111/j.1471-4159.2008.05680.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Amyloid beta-peptide (Abeta) plays a fundamental role in the pathogenesis of Alzheimer's disease. We recently reported that the redox state of the methionine residue in position 35 of amyloid beta-peptide (Abeta) 1-42 (Met35) strongly affects the peptide's ability to trigger apoptosis and is thus a major determinant of its neurotoxicity. Dysregulation of intracellular Ca(2+) homeostasis resulting in the activation of pro-apoptotic pathways has been proposed as a mechanism underlying Abeta toxicity. Therefore, we investigated correlations between the Met35 redox state, Abeta toxicity, and altered intracellular Ca(2+) signaling in human neuroblastoma IMR32 cells. Cells incubated for 6-24 h with 10 microM Abeta1-42 exhibited significantly increased KCl-induced Ca(2+) transient amplitudes and resting free Ca(2+) concentrations. Nifedipine-sensitive Ca(2+) current densities and Ca(v)1 channel expression were markedly enhanced by Abeta1-42. None of these effects were observed when cells were exposed to Abeta containing oxidized Met35 (Abeta1-42(Met35-Ox)). Cell pre-treatment with the intracellular Ca(2+) chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (1 microM) or the Ca(v)1 channel blocker nifedipine (5 microM) significantly attenuated Abeta1-42-induced apoptosis but had no effect on Abeta1-42(Met35-Ox) toxicity. Collectively, these data suggest that reduced Met35 plays a critical role in Abeta1-42 toxicity by rendering the peptide capable of disrupting intracellular Ca(2+) homeostasis and thereby provoking apoptotic cell death.
Collapse
Affiliation(s)
- Roberto Piacentini
- Institute of Human Physiology, Medical School, Catholic University S Cuore, Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Sun ZK, Yang HQ, Pan J, Zhen H, Wang ZQ, Chen SD, Ding JQ. Protective effects of erythropoietin on tau phosphorylation induced by beta-amyloid. J Neurosci Res 2008; 86:3018-27. [PMID: 18512763 DOI: 10.1002/jnr.21745] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neuropathological studies have demonstrated that the presence of neurofibrillary tangles (NFTs) is one of the most prominent pathologic characteristics of Alzheimer's disease (AD). The microtubule-associated protein tau is the major component of NFTs, and its abnormal hyperphosphorylation leads to the destabilization of microtubules, impaired axonal transport, and eventual death of the neurons. The hematopoietic cytokine erythropoietin (Epo) is now considered as a viable agent with regard to central nervous system injury in a variety of cellular systems. Here we report that Epo prevented tau hyperphosphorylation in SH-SY5Y cells exposed to the beta-amyloid peptide and that this effect may depend on the PI3K/Akt-GSK-3beta pathway. This study provides new molecular insight into the neuroprotective effect of Epo and suggests its possible therapeutic role in the management of AD.
Collapse
Affiliation(s)
- Zhi-Kun Sun
- Department of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
32
|
Huang SH, Lin CM, Chiang BH. Protective effects of Angelica sinensis extract on amyloid beta-peptide-induced neurotoxicity. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2008; 15:710-21. [PMID: 18448320 DOI: 10.1016/j.phymed.2008.02.022] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2007] [Revised: 11/18/2007] [Accepted: 02/20/2008] [Indexed: 05/22/2023]
Abstract
The protective effects of alcohol extract from the root of Angelica sinensis (AS) on beta-amyloid peptide (Abeta)-induced toxicity and the mechanism of these effects were investigated. Abeta is a pathological hallmark of Alzheimer's disease; it decreased viability of Neuro 2A cells in a concentration-dependent manner with IC(50) of 14.9 microM. AS extract resulted in dose-dependent anti-Abeta toxicity according to MTT assay. Reactive oxygen species (ROS) analysis revealed a significant production of hydrogen peroxide, decreased glutathione (GSH) levels and increased lipid peroxidation (TBARS value) in the Abeta-treated Neuro 2A cells. The Abeta-treated cells also showed a significant decline in the mitochondrial transmembrane potential (DeltaPsim) and increase in the mitochondrial volume, and portions of the cytoplasm were sequestered by a membrane-bound vacuole. The malfunctions of Neuro 2A cells caused by Abeta were attenuated using AS extract. The AS extract protected cell viability against Abeta-induced oxidative damage (ROS, TBARS, and GSH contents) and rescued the DeltaPsim levels in a dose-dependent manner: the dosages of 25, 50, 100, and 200 microg/ml recovered 77%, 87%, 102%, and 105% of DeltaPsim, respectively. AS extract also recovered the enlarged mitochondria mass with dosages from 25 to 200 microg/ml. The results of this study demonstrated that AS extract possessed the activity to prevent the neurotoxicity induced by Abeta-associated oxidative stress, implying that AS has a potential role in the prevention of Alzheimer's diseases.
Collapse
Affiliation(s)
- Shih-Hao Huang
- Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan
| | | | | |
Collapse
|
33
|
Frozza RL, Horn AP, Hoppe JB, Simão F, Gerhardt D, Comiran RA, Salbego CG. A comparative study of beta-amyloid peptides Abeta1-42 and Abeta25-35 toxicity in organotypic hippocampal slice cultures. Neurochem Res 2008; 34:295-303. [PMID: 18686032 DOI: 10.1007/s11064-008-9776-8] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Accepted: 06/09/2008] [Indexed: 12/28/2022]
Abstract
Accumulation of the neurotoxic amyloid beta-peptide (Abeta) in the brain is a hallmark of Alzheimer's disease (AD). Several synthetic Abeta peptides have been used to study the mechanisms of toxicity. Here, we sought to establish comparability between two commonly used Abeta peptides Abeta1-42 and Abeta25-35 on an in vitro model of Abeta toxicity. For this purpose we used organotypic slice cultures of rat hippocampus and observed that both Abeta peptides caused similar toxic effects regarding to propidium iodide uptake and caspase-3 activation. In addition, we also did not observe any effect of both peptides on Akt and PTEN phosphorylation; otherwise the phosphorylation of GSK-3beta was increased. Although further studies are necessary for understanding mechanisms underlying Abeta peptide toxicity, our results provide strong evidence that Abeta1-42 and the Abeta25-35 peptides induce neural injury in a similar pattern and that Abeta25-35 is a convenient tool for the investigation of neurotoxic mechanisms involved in AD.
Collapse
Affiliation(s)
- Rudimar Luiz Frozza
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul - UFRGS, Av. Ramiro Barcelos, 2600 - anexo, Porto Alegre, RS, CEP 90035-003, Brazil
| | | | | | | | | | | | | |
Collapse
|
34
|
Wu MN, He YX, Guo F, Qi JS. Alpha4beta2 nicotinic acetylcholine receptors are required for the amyloid beta protein-induced suppression of long-term potentiation in rat hippocampal CA1 region in vivo. Brain Res Bull 2008; 77:84-90. [PMID: 18602971 DOI: 10.1016/j.brainresbull.2008.06.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2008] [Revised: 06/06/2008] [Accepted: 06/08/2008] [Indexed: 11/26/2022]
Abstract
Amyloid beta protein (Abeta) is thought to be responsible for the deficit of learning and memory in Alzheimer's disease (AD), possibly through interfering with synaptic plasticity such as hippocampal long-term potentiation (LTP). Nicotinic acetylcholine receptors (nAChRs) participate in various cognitive brain functions. However, it is unclear whether nAChRs, especially alpha4beta2 subtype nAChRs, are involved in Abeta-induced impairment of hippocampal LTP. The present study investigates a possible role of nAChRs during the impairment of LTP by Abeta. Our results showed that: (1) intracerebroventricular injection of Abeta(1-40), Abeta(25-35) or Abeta(31-35) significantly suppressed high-frequency stimulation-induced LTP, while Abeta(35-31), a reversed sequence of Abeta(31-35), have no effect on the LTP; (2) epibatidine, a specific agonist of alpha4beta2 subtype of nAChRs, dose-dependently suppressed the induction of LTP; (3) co-injection of epibatidine together with Abeta(31-35) did not further enhance the suppression of LTP induced by Abeta(31-35) or epibatidine alone; (4) dihydro-beta-erythroidine, a selective antagonist against alpha4beta2 subtype of nAChRs, showed no effect on the induction of LTP, but significantly reversed Abeta(31-35)-induced LTP impairment. These results indicate that: (1) sequence 31-35 in Abeta molecule might be a shorter active center responsible for the neurotoxicity of full length of Abeta; (2) alpha4beta2 subtype of nAChRs is required for the suppressive action of Abeta on the hippocampal LTP in vivo. Thus, the present study provides further insight into the mechanisms by which Abeta impairs synaptic plasticity and cognitive function in the AD brain.
Collapse
Affiliation(s)
- M N Wu
- Department of Neurobiology and the national key discipline of physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | | | | | | |
Collapse
|
35
|
Patel NS, Quadros A, Brem S, Wotoczek-Obadia M, Mathura VS, Laporte V, Mullan M, Paris D. Potent anti-angiogenic motifs within the Alzheimer beta-amyloid peptide. Amyloid 2008; 15:5-19. [PMID: 18266117 DOI: 10.1080/13506120701814723] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Abeta peptides are the major constituents of senile plaques and cerebrovascular deposits in the brains of patients with Alzheimer's disease. We have shown previously that Abeta1-40 and Abeta1-42 peptides are potently anti-angiogenic both in vitro and in vivo. The current study characterizes important sequences within the Abeta peptide that are required to exert its anti-angiogenic activity. We have used human umbilical vein endothelial cells to assess the anti-angiogenic activity of short fragments of Abetain vitro in a Matrigel network assay and in vivo in a rat corneal model of angiogenesis. The anti-angiogenic activity of these short peptide fragments is not related to effects on apoptosis or necrosis. Using normal and mutated peptide fragments, we show that the sequence VHHQKLVFF is sufficient to exhibit potent anti-angiogenic effects. This small peptide may therefore have clinical relevance as an anti-angiogenic agent.
Collapse
|
36
|
Zhao L, Qian ZM, Zhang C, Wing HY, Du F, Ya K. Amyloid beta-peptide 31-35-induced neuronal apoptosis is mediated by caspase-dependent pathways via cAMP-dependent protein kinase A activation. Aging Cell 2008; 7:47-57. [PMID: 18005252 DOI: 10.1111/j.1474-9726.2007.00352.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
This study aims to investigate the roles of the protein kinase A (PKA)- and caspase-dependent pathways in amyloid beta-peptide 31-35 (Abeta[31-35])-induced apoptosis, and the mechanisms of neuroprotection by group III metabotropic glutamate receptor (mGluR) activation against apoptosis induced by Abeta[31-35] in cortical neurons. We demonstrated that Abeta[31-35] induces neuronal apoptosis as well as a significant increase in caspase-3, -8 and -9. Activation of group III mGluRs by l-serine-O-phosphate and (R,S)-4-phosphonophenylglycine (two group III mGluR agonists), which attenuate the effects of Abeta[31-35], provides neuroprotection to the cortical neurons subjected to Abeta[31-35]. We also showed that Rp-cAMP, an inhibitor of cAMP-dependent PKA, has the ability to protect neurons from Abeta[31-35]-induced apoptosis and to reverse almost completely the effects of Abeta[31-35] on the activities of caspase-3. Further, we found that Sp-cAMP, an activator of cAMP-dependent PKA, can significantly abolish the l-serine-O-phosphate- and (R,S)-4-phosphonophenylglycine-induced neuroprotection against apoptosis, and decrease caspase-3, -8 and -9 in the Abeta[31-35]-treated neurons. Our findings suggest that neuronal apoptosis induced by Abeta[31-35] is mediated by the PKA-dependent pathway as well as the caspase-dependent intrinsic and extrinsic apoptotic pathways. Activation of group III mGluRs protects neurons from Abeta[31-35]-induced apoptosis by blocking the caspase-dependent pathways. Inhibition of the PKA-dependent pathway might also protect neurons from Abeta[31-35]-induced apoptosis by blocking the caspase-dependent pathways. Taken together, our observations suggest that Abeta[31-35] might have the ability to activate PKA, which in turn activates the caspase-dependent intrinsic and extrinsic apoptotic pathways, inducing apoptosis in the cortical neurons.
Collapse
Affiliation(s)
- Li Zhao
- Department of Sports Physiology, Beijing Sport University, Beijing 100084, China
| | | | | | | | | | | |
Collapse
|
37
|
Xiong ZM, Kitagawa K, Nishiuchi Y, Kimura T, Inagaki C. Protective effects of Aβ-derived tripeptide, Aβ32–34, on Aβ1–42-induced phosphatidylinositol 4-kinase inhibition and neurotoxicity. Neurosci Lett 2007; 419:247-52. [PMID: 17499922 DOI: 10.1016/j.neulet.2007.04.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 04/10/2007] [Accepted: 04/10/2007] [Indexed: 12/20/2022]
Abstract
We previously reported that the neurotoxicity of pathophysiological concentrations of amyloid beta proteins (Abetas, 0.1-10nM) as assessed by the inhibition of type II phosphatidylinositol 4-kinase (PI4KII) activity and the enhancement of glutamate toxicity was blocked by a short fragment of Abeta, Abeta(31-35). Such protective effects of shorter fragments derived from Abeta(31-35) were examined in this study to reach the shortest effective peptide, using recombinant human PI4KII and primary cultured rat hippocampal neurons. Among the peptides tested (Abeta(31-34), Abeta(31-33), Abeta(31-32), Abeta(32-35), Abeta(33-35), Abeta(34-35), Abeta(32-34), Abeta(33-34) and Abeta(32-33)), Abeta(31-34), Abeta(32-35) and Abeta(32-34) blocked both the Abeta(1-42)-induced inhibition of PI4KII activity and enhancement of glutamate toxicity on cell viability. The shortest peptide among them, Abeta(32-34), showed a dose-dependent protective effect with 50% effective concentration near 1nM, while Abeta(34-32), with a reverse amino acid sequence for Abeta(32-34), showed no protective effects. Thus, a tripeptide, Abeta(32-34) i.e. Ile-Gly-Leu, may be available as a lead compound for designing effective Abeta antagonists.
Collapse
Affiliation(s)
- Zheng-Mei Xiong
- Department of Pharmacology, Kansai Medical University, Fumizono-cho 10-15, Moriguchi, Osaka 570-8506, Japan
| | | | | | | | | |
Collapse
|
38
|
Uberti D, Ferrari-Toninelli G, Bonini SA, Sarnico I, Benarese M, Pizzi M, Benussi L, Ghidoni R, Binetti G, Spano P, Facchetti F, Memo M. Blockade of the tumor necrosis factor-related apoptosis inducing ligand death receptor DR5 prevents beta-amyloid neurotoxicity. Neuropsychopharmacology 2007; 32:872-80. [PMID: 16936710 DOI: 10.1038/sj.npp.1301185] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We originally suggested that inhibition of tumor necrosis factor-related apoptosis inducing ligand (TRAIL) death pathway could be taken into consideration as a potential therapeutic strategy for Alzheimer's disease (AD). However, because the critical role of TRAIL in immune surveillance, the neutralization of TRAIL protein by an antibody to prevent its binding to death receptors is definitely a risky approach. Here, we demonstrated that the blockade of the TRAIL death receptor DR5 with a specific antibody completely prevented amyloid beta peptide (A beta) neurotoxicity in both neuronal cell line and primary cortical neurons. DR5 was demonstrated to be a key factor in TRAIL death pathway. In fact, whereas TRAIL expression was enhanced dose-dependently by concentrations of beta amyloid ranging from 10 nM to 1 microM, only the highest toxic dose of A beta (25 microM) induced the increased expression of DR5 and neuronal cell death. In addition, the increased expression of DR5 receptor after beta amyloid treatment was sustained by p53 transcriptional activity, as demonstrated by the data showing that the p53 inhibitor Pifithrin alpha prevented both beta amyloid-induced DR5 induction and cell death. These data suggest a sequential activation of p53 and DR5 upon beta amyloid exposure. Further insight into the key role of DR5 in AD was suggested by data showing a significant increase of DR5 receptor in cortical slices of AD brain. Thus, these findings may give intracellular TRAIL pathway a role in AD pathophysiology, making DR5 receptor a possible candidate as a pharmacological target.
Collapse
Affiliation(s)
- Daniela Uberti
- Department of Biomedical Sciences and Biotechnologies, University of Brescia Medical School, Brescia, Italy.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Nuutinen T, Huuskonen J, Suuronen T, Ojala J, Miettinen R, Salminen A. Amyloid-β 1–42 induced endocytosis and clusterin/apoJ protein accumulation in cultured human astrocytes. Neurochem Int 2007; 50:540-7. [PMID: 17196306 DOI: 10.1016/j.neuint.2006.11.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 10/24/2006] [Accepted: 11/02/2006] [Indexed: 02/05/2023]
Abstract
Recent studies indicate that astrocytes may be the primary target of secreted amyloid-beta 1-42 peptides, with the neurotoxicity representing a secondary response to astrocytic stress. Our purpose was to clarify the astrocytic stress response induced by amyloid-beta peptides in human and rat astrocytes. Human amyloid-beta 1-42 peptides and fibrils induced the appearance of cytoplasmic vacuoles in normal human astrocytes (NHA) and CCFsttg1 astrocytoma cells. Vacuoles appeared 9-12h after the amyloid-beta exposure and remained present for several days. Rat primary neonatal astrocytes showed similar but less prominent vacuolar response. Human amyloid-beta peptides 1-16, 1-28, 10-20, 17-21 and 25-35 did not cause vacuole formation. Electron microscopic observations revealed large endocytic vacuoles containing fibrillar amyloid material. Stress marker analysis did not show any increase in protein levels of HSP70, HSP90, GRP78 and GRP94. However, the protein level of clusterin/apoJ, a secreted chaperone, was strongly increased both in NHA and CCFsttg1 astrocytes. Endocytic response associated with the accumulation of clusterin/apoJ protein suggests that clusterin/apoJ has a role in the clearance of amyloid-beta peptides.
Collapse
Affiliation(s)
- Tapio Nuutinen
- Department of Neuroscience and Neurology, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland
| | | | | | | | | | | |
Collapse
|
40
|
Nassif M, Hoppe J, Santin K, Frozza R, Zamin LL, Simão F, Horn AP, Salbego C. β-Amyloid peptide toxicity in organotypic hippocampal slice culture involves Akt/PKB, GSK-3β, and PTEN. Neurochem Int 2007; 50:229-35. [PMID: 17018242 DOI: 10.1016/j.neuint.2006.08.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2006] [Revised: 08/03/2006] [Accepted: 08/14/2006] [Indexed: 12/20/2022]
Abstract
In the present study we investigated the toxicity induced by exposing organotypic slice culture to beta-amyloid peptide 25-35 (25microM) for 1, 3, 6, 12, 24 and 48h. To elucidate a mechanism involved in its toxicity, we studied the PI3-K cell signaling pathway, particularly Akt/PKB, GSK-3beta, and PTEN proteins. Cell death was quantified by propidium iodide uptake and proteins were analyzed by immunoblotting. Our results showed a significant cell death after 48h of beta-amyloid 25-35 peptide exposition. The exposition of cultures to beta-amyloid peptide resulted in an increase in the phosphorylation state of Akt and GSK-3beta proteins after 6h, followed by a decrease of the phosphorylation state of these proteins after 12h of exposition. However, after 24h of peptide treatment, the phosphorylation of GSK-3beta presented a new increase while the phosphorylation of Akt remained down. The immunocontent of the PTEN protein, an indirect Akt phosphatase, increased after 24 and 48h of beta-amyloid exposition. These results suggest an involvement of Akt dephosphorylation/inactivation in the toxicity induced by the beta-amyloid 25-35 peptide in organotypic slice hippocampal culture, probably induced by increasing PTEN immunocontent. Taken together, our results provide more information about the molecular mechanisms involved on beta-amyloid peptide toxicity.
Collapse
Affiliation(s)
- Melissa Nassif
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, 90035-003 Porto Alegre, RS, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Zhang YH, Zhang HJ, Wu F, Chen YH, Ma XQ, Du JQ, Zhou ZL, Li JY, Nan FJ, Li J. Isoquinoline-1,3,4-trione and its derivatives attenuate ?-amyloid-induced apoptosis of neuronal cells. FEBS J 2006; 273:4842-52. [PMID: 17032354 DOI: 10.1111/j.1742-4658.2006.05483.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Caspase-3 is a programmed cell death protease involved in neuronal apoptosis during physiological development and under pathological conditions. It is a promising therapeutic target for treatment of neurodegenerative diseases. We reported previously that isoquinoline-1,3,4-trione and its derivatives inhibit caspase-3. In this report, we validate isoquinoline-1,3,4-trione and its derivatives as potent, selective, irreversible, slow-binding and pan-caspase inhibitors. Furthermore, we show that these inhibitors attenuated apoptosis induced by beta-amyloid(25-35) in PC12 cells and primary neuronal cells.
Collapse
Affiliation(s)
- Ya-Hui Zhang
- National Center for Drug Screening, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Misiti F, Clementi ME, Tringali G, Vairano M, Orsini F, Pezzotti M, Navarra P, Giardina B, Pozzoli G. Fragment 31–35 of β-amyloid peptide induces neurodegeneration in rat cerebellar granule cells via bax gene expression and caspase-3 activation. Neurochem Int 2006; 49:525-32. [PMID: 16720060 DOI: 10.1016/j.neuint.2006.03.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 03/30/2006] [Indexed: 10/24/2022]
Abstract
The amyloid beta-peptide (AbetaP) is the major protein component of brain senile plaques in Alzheimer's disease. The redox state of methionine-35 residue plays a critical role in peptide neurotoxic actions. We used the fragment 31-35 of AbetaP [AbetaP(31-35)], containing a single methionine-35 residue (Met-35), to investigate the relationship between the oxidative state of Met-35 and neurotoxic and pro-apoptotic actions induced by the peptide; in rat cerebellar granule cells (CGC), we compared the effects of AbetaP(31-35), in which the Met-35 is present in the reduced state, with those of a modified peptide with oxidized Met-35 [AbetaP(31-35)Met-35(OX)](,) as well as an AbetaP-derivative with Met-35 substituted by norleucine [AbetaP(31-35)Nle-35]. AbetaP(31-35) induced a time-dependent decrease in cell viability. AbetaP(31-35)Met-35(OX) was significantly less potent, but still induced a significant decrease in cell viability compared to control. No toxic effects were observed after treatment with AbetaP(31-35)Nle-35. AbetaP(31-35) induced a 2-fold increase in bax mRNA levels after 4h, whereas AbetaP(31-35)Met-35(OX) raised bax mRNA levels by 41% and AbetaP(31-35)Nle-35 had no effect. Finally, AbetaP(31-35) caused a 43% increase in caspase-3 activity after 24h; AbetaP(31-35)Met-35(OX) caused only a 18% increase, and AbetaP(31-35)Nle-35 had no effect. These findings suggest that AbetaP(31-35)-induced neurodegeneration in CGC is mediated by a selective early increase in bax mRNA levels followed by delayed caspase-3 activation; the redox state of the single Met-35 residue is crucial in the occurrence and extent of the above phenomena.
Collapse
Affiliation(s)
- Francesco Misiti
- Institute of Biochemistry and Clinical Biochemistry, Catholic University School of Medicine, Largo F. Vito 1, 00168 Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
The free energy landscape for folding of the Alzheimer's amyloid-beta(25-35) peptide is explored using replica exchange molecular dynamics in both pure water and in HFIP/water cosolvent. This amphiphilic peptide is a natural by-product of the Alzheimer's amyloid-beta(1-40) peptide and retains the toxicity of its full-length counterpart as well as the ability to aggregate into beta-sheet-rich fibrils. Our simulations reveal that the peptide preferentially populates a helical structure in apolar organic solvent, while in pure water, the peptide adopts collapsed coil conformations and to a lesser extent beta-hairpin conformations. The beta-hairpin is characterized by a type II' beta-turn involving residues G29 and A30 and two short beta-strands involving residues N27, K28, I31, and I32. The hairpin is stabilized by backbone hydrogen-bonding interactions between residues K28 and I31; S26 and G33; and by side-chain-to-side-chain interactions between N27 and I32. Implications regarding the mechanism of aggregation of this peptide into fibrils and the role of the environment in modulating secondary structure are discussed.
Collapse
Affiliation(s)
- Guanghong Wei
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, USA
| | | |
Collapse
|
44
|
Wu B, Kitagawa K, Liu B, Zhang NY, Xiong ZM, Inagaki C. Attenuation of amyloid β (Aβ)-induced inhibition of phosphatidylinositol 4-kinase activity by Aβ fragments, Aβ20–29 and Aβ31–35. Neurosci Lett 2006; 396:148-52. [PMID: 16356635 DOI: 10.1016/j.neulet.2005.11.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 11/04/2005] [Accepted: 11/12/2005] [Indexed: 11/25/2022]
Abstract
We previously reported that pathophysiological concentrations of amyloid beta protein (Abeta25-35, 0.1-10 nM) directly inhibited type II phosphatidylinositol 4-kinase (PI4KII) activity in neuronal plasma membranes, which resulted in the enhanced glutamate neurotoxicity. In the present study, we examined the effects of Abeta fragments, Abeta20-29 and Abeta31-35, on the 10 nM Abeta25-35- or Abeta1-42-induced inhibition of PI4KII activity. Both of the peptide fragments recovered the inhibition of rat brain plasma membrane PI4KII activity over the concentration range of 0.1-5 nM. Such protection by the Abeta fragments was observed in the 10 nM Abeta25-35-induced inhibition of recombinant human PI4KII, suggesting that these Abeta fragments blocked the inhibition on PI4KII molecule. The Abeta25-35-induced enhancement of glutamate neurotoxicity was also completely inhibited in the presence of these fragments. Thus, Abeta20-29 and Abeta31-35 ameliorated the Abeta-enhanced glutamate neurotoxicity probably through attenuation of Abeta-induced inhibition of PI4KII activity.
Collapse
Affiliation(s)
- Bo Wu
- Department of Pharmacology, Kansai Medical University, Fumizono-cho 10-15, Moriguchi-City, Osaka 570-8506, Japan
| | | | | | | | | | | |
Collapse
|
45
|
Clementi ME, Pezzotti M, Orsini F, Sampaolese B, Mezzogori D, Grassi C, Giardina B, Misiti F. Alzheimer's amyloid beta-peptide (1-42) induces cell death in human neuroblastoma via bax/bcl-2 ratio increase: an intriguing role for methionine 35. Biochem Biophys Res Commun 2006; 342:206-13. [PMID: 16472763 DOI: 10.1016/j.bbrc.2006.01.137] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Accepted: 01/26/2006] [Indexed: 11/18/2022]
Abstract
The beta amyloid (Abeta), the major protein component of brain senile plaques in Alzheimer's disease, is known to be directly responsible for the production of free radicals toxic to brain tissue and the redox state of Met-35 residue seems to play a particular and critical role in peptide's neurotoxic actions. In this study, we investigated, in human neuroblastoma cells (IMR-32), the relationship between the oxidative state of methionine, and both neurotoxic and pro-apoptotic actions induced by Abeta-peptide, comparing the effects of native peptide, in which the Met-35 is present in the reduced state, with those of a modified peptide with oxidized Met-35 (Abeta(1-42)(35Met-ox)), as well as an Abeta-derivative with Met-35 substituted with norleucine (Abeta(1-42)(35Nle)). The obtained results show that Abeta induces a time-dependent decrease in cell viability; Abeta(1-42)(35Met-ox) was significantly less potent, though inducing a remarkable decrease in cell viability compared to control. On the contrary, no toxic effects were observed after treatment with Abeta(1-42)(35Nle). Abeta-peptide as well as the amyloid modified peptide with oxidized Met-35 induced the pro-apoptotic gene bax over-expression after 24 h, whereas Abeta(1-42)(35Nle) had no effect. Conversely, bcl-2, an anti-apoptotic gene, became highly down-regulated by Abeta peptide treatment, in contrast to that evidenced by the Abeta(1-42)(35Met-ox) peptide. Finally, Abeta caused an increase in caspase-3 activity to be higher with respect to that shown by Abeta(1-42)(35Met-ox) while Abeta(1-42)(35Nle) had no effect. These results support the hypothesis that Abeta-induced neurotoxicity occurs via bax over-expression, bcl-2 down-regulation, and caspase-3 activation, first indicating that methionine 35 redox state may alter this cell death pathway.
Collapse
Affiliation(s)
- M E Clementi
- CNR-ICRM, Institute of Chimica del Riconoscimento Molecolare, c/o Institute of Biochemistry and Clinical Biochemistry, Catholic University School of Medicine, Largo F. Vito 1, 00168 Rome, Italy
| | | | | | | | | | | | | | | |
Collapse
|
46
|
. CCA, . MP, . DM, . MEC, . FM, . BG, . FO. Aß(25-35) Peptide Induces Cell Death in PC12 Cells via Mitochondrial Damage and Cytochrome c Release. ACTA ACUST UNITED AC 2005. [DOI: 10.3923/jbs.2006.140.145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|