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Funke SA, Bartnik D, Glück JM, Piorkowska K, Wiesehan K, Weber U, Gulyas B, Halldin C, Pfeifer A, Spenger C, Muhs A, Willbold D. Development of a small D-enantiomeric Alzheimer's amyloid-β binding peptide ligand for future in vivo imaging applications. PLoS One 2012; 7:e41457. [PMID: 22848501 PMCID: PMC3404088 DOI: 10.1371/journal.pone.0041457] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Accepted: 06/25/2012] [Indexed: 11/18/2022] Open
Abstract
Alzheimer’s disease (AD) is a devastating disease affecting predominantly the aging population. One of the characteristic pathological hallmarks of AD are neuritic plaques, consisting of amyloid-β peptide (Aβ). While there has been some advancement in diagnostic classification of AD patients according to their clinical severity, no fully reliable method for pre-symptomatic diagnosis of AD is available. To enable such early diagnosis, which will allow the initiation of treatments early in the disease progress, neuroimaging tools are under development, making use of Aβ-binding ligands that can visualize amyloid plaques in the living brain. Here we investigate the properties of a newly designed series of D-enantiomeric peptides which are derivatives of ACI-80, formerly called D1, which was developed to specifically bind aggregated Aβ1–42. We describe ACI-80 derivatives with increased stability and Aβ binding properties, which were characterized using surface plasmon resonance and enzyme-linked immunosorbent assays. The specific interactions of the lead compounds with amyloid plaques were validated by ex vivo immunochemistry in transgenic mouse models of AD. The novel compounds showed increased binding affinity and are promising candidates for further development into in vivo imaging compounds.
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Affiliation(s)
| | - Dirk Bartnik
- Forschungszentrum Jülich, ICS-6, Jülich, Germany
| | | | | | | | - Urs Weber
- AC Immune, PSE Building B, EPFL, Lausanne, Switzerland
| | - Balazs Gulyas
- Psychiatry Section, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Christer Halldin
- Psychiatry Section, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Christian Spenger
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
- Prodema Management AG, Bronschhofen, Switzerland
| | - Andreas Muhs
- AC Immune, PSE Building B, EPFL, Lausanne, Switzerland
| | - Dieter Willbold
- Forschungszentrum Jülich, ICS-6, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
- * E-mail:
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Alldred MJ, Duff KE, Ginsberg SD. Microarray analysis of CA1 pyramidal neurons in a mouse model of tauopathy reveals progressive synaptic dysfunction. Neurobiol Dis 2012; 45:751-62. [PMID: 22079237 PMCID: PMC3259262 DOI: 10.1016/j.nbd.2011.10.022] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Accepted: 10/28/2011] [Indexed: 11/24/2022] Open
Abstract
The hTau mouse model of tauopathy was utilized to assess gene expression changes in vulnerable hippocampal CA1 neurons. CA1 pyramidal neurons were microaspirated via laser capture microdissection followed by RNA amplification in combination with custom-designed microarray analysis and qPCR validation in hTau mice and nontransgenic (ntg) littermates aged 11-14months. Statistical analysis revealed ~8% of all the genes on the array platform were dysregulated, with notable downregulation of several synaptic-related markers including synaptophysin (Syp), synaptojanin, and synaptobrevin, among others. Downregulation was also observed for select glutamate receptors (GluRs), Psd-95, TrkB, and several protein phosphatase subunits. In contrast, upregulation of tau isoforms and a calpain subunit were found. Microarray assessment of synaptic-related markers in a separate cohort of hTau mice at 7-8months of age indicated only a few alterations compared to the 11-14month cohort, suggesting progressive synaptic dysfunction occurs as tau accumulates in CA1 pyramidal neurons. An assessment of SYP and PSD-95 expression was performed in the hippocampal CA1 sector of hTau and ntg mice via confocal laser scanning microscopy along with hippocampal immunoblot analysis for protein-based validation of selected microarray observations. Results indicate significant decreases in SYP-immunoreactive and PSD-95-immunoreactive puncta as well as downregulation of SYP-immunoreactive and PSD-95-immunoreactive band intensity in hTau mice compared to age-matched ntg littermates. In summary, the high prevalence of downregulation of synaptic-related genes indicates that the moderately aged hTau mouse may be a model of tau-induced synaptodegeneration, and has profound effects on how we perceive progressive tau pathology affecting synaptic transmission in AD.
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Affiliation(s)
- Melissa J. Alldred
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY
- Department of Psychiatry, New York University Langone Medical Center, New York, NY
| | - Karen E. Duff
- Taub Institute and Department of Pathology, Columbia University Medical Center, New York, NY
| | - Stephen D. Ginsberg
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY
- Department of Psychiatry, New York University Langone Medical Center, New York, NY
- Department of Physiology, Neuroscience, New York University Langone Medical Center, New York, NY
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Yan J, Sun XB, Wang HQ, Zhao H, Zhao XY, Xu YX, Guo JC, Zhu CQ. Chronic restraint stress alters the expression and distribution of phosphorylated tau and MAP2 in cortex and hippocampus of rat brain. Brain Res 2010; 1347:132-41. [PMID: 20513368 DOI: 10.1016/j.brainres.2010.05.074] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Revised: 05/18/2010] [Accepted: 05/24/2010] [Indexed: 12/30/2022]
Abstract
Microtubule-associated proteins (MAPs) play a critical role in maintaining normal cytoskeletal architecture and functions. In the present study, we aim to explore the effects of the emotional stressor, chronic restraint stress, on the expression levels and localization of tau and MAP2. We found that after chronic restraint stress, soluble hyperphosphorylated tau was greatly increased, whereas MAP2 was decreased. Moreover, immunohistochemistry analysis demonstrated that phosphorylated tau and MAP2 displayed the similar subcellular distribution pattern after chronic restraint stress. Robust hyperphosphorylated tau immunolabeling was observed both in cortex and hippocampus of stressed animals and mainly located to perikaryal/dendritic elements. After stress, the MAP2 was mainly distributed in the perikaryal compartments, discontinuous dendrites and neuropil. Moreover, the distribution pattern of MAP2 in hippocampus significantly changed. Immunofluorescence double labeling indicated that hyperphosphorylated tau increased in the regions where there displayed an decrease of MAP2. These results suggest that the involvement of repeated restraint stress may not only induce phosphorylation state of tau and distribution of phosphorylated tau, but also alter the content and neuronal distribution of MAP2. Tau and MAP2 are most important MAPs for neuronal cells, the subcellular distribution change of them might be link to functional change of neurons after emotional stress.
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Affiliation(s)
- Jie Yan
- State Key Laboratory of Medical Neurobiology and Department of Neurobiology, Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032, PR China
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van Groen T, Kadish I, Wiesehan K, Funke S, Willbold D. In vitro and in vivo Staining Characteristics of Small, Fluorescent, Aβ42-Binding D-Enantiomeric Peptides in Transgenic AD Mouse Models. ChemMedChem 2009; 4:276-82. [DOI: 10.1002/cmdc.200800289] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Farah CA, Leclerc N. HMWMAP2: New perspectives on a pathway to dendritic identity. ACTA ACUST UNITED AC 2008; 65:515-27. [DOI: 10.1002/cm.20284] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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