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Nikiforova A, Sedov I. Molecular Design of Magnetic Resonance Imaging Agents Binding to Amyloid Deposits. Int J Mol Sci 2023; 24:11152. [PMID: 37446329 DOI: 10.3390/ijms241311152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 06/27/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
The ability to detect and monitor amyloid deposition in the brain using non-invasive imaging techniques provides valuable insights into the early diagnosis and progression of Alzheimer's disease and helps to evaluate the efficacy of potential treatments. Magnetic resonance imaging (MRI) is a widely available technique offering high-spatial-resolution imaging. It can be used to visualize amyloid deposits with the help of amyloid-binding diagnostic agents injected into the body. In recent years, a number of amyloid-targeted MRI probes have been developed, but none of them has entered clinical practice. We review the advances in the field and deduce the requirements for the molecular structure and properties of a diagnostic probe candidate. These requirements make up the base for the rational design of MRI-active small molecules targeting amyloid deposits. Particular attention is paid to the novel cryo-EM structures of the fibril aggregates and their complexes, with known binders offering the possibility to use computational structure-based design methods. With continued research and development, MRI probes may revolutionize the diagnosis and treatment of neurodegenerative diseases, ultimately improving the lives of millions of people worldwide.
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Affiliation(s)
- Alena Nikiforova
- Chemical Institute, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia
| | - Igor Sedov
- Chemical Institute, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia
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2
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Gharai PK, Khan J, Mallesh R, Garg S, Saha A, Ghosh S, Ghosh S. Vanillin Benzothiazole Derivative Reduces Cellular Reactive Oxygen Species and Detects Amyloid Fibrillar Aggregates in Alzheimer's Disease Brain. ACS Chem Neurosci 2023; 14:773-786. [PMID: 36728363 DOI: 10.1021/acschemneuro.2c00771] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The misfolding of amyloid beta (Aβ) peptides into Aβ fibrillary aggregates is a major hallmark of Alzheimer's disease (AD), which responsible for the excess production of hydrogen peroxide (H2O2), a prominent reactive oxygen species (ROS) from the molecular oxygen (O2) by the reduction of the Aβ-Cu(I) complex. The excessive production of H2O2 causes oxidative stress and inflammation in the AD brain. Here, we have designed and developed a dual functionalized molecule VBD by using π-conjugation (C═C) in the backbone structure. In the presence of H2O2, the VBD can turn into fluorescent probe VBD-1 by cleaving of the selective boronate ester group. The fluorescent probe VBD-1 can undergo intramolecular charge transfer transition (ICT) by a π-conjugative system, and as a result, its emission increases from the yellow (532 nm) to red (590 nm) region. The fluorescence intensity of VBD-1 increases by 3.5-fold upon binding with Aβ fibrillary aggregates with a high affinity (Kd = 143 ± 12 nM). Finally, the VBD reduces the cellular toxic H2O2 as proven by the CCA assay and DCFDA assay and the binding affinity of VBD-1 was confirmed by using in vitro histological staining in 8- and 18-month-old triple transgenic AD (3xTg-AD) mice brain slices.
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Affiliation(s)
- Prabir Kumar Gharai
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India.,Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India
| | - Juhee Khan
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India.,Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India
| | - Rathnam Mallesh
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India.,Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India.,National Institute of Pharmaceutical Education and Research, Kolkata, Chunilal Bhawan 168, Maniktala Main Road, Kolkata 700054, India
| | - Shubham Garg
- Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India
| | - Abhijit Saha
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur, Chennai 603203, India
| | - Subhajit Ghosh
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India
| | - Surajit Ghosh
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India.,Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India.,National Institute of Pharmaceutical Education and Research, Kolkata, Chunilal Bhawan 168, Maniktala Main Road, Kolkata 700054, India
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3
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Mallesh R, Khan J, Pradhan K, Roy R, Jana NR, Jaisankar P, Ghosh S. Design and Development of Benzothiazole-Based Fluorescent Probes for Selective Detection of Aβ Aggregates in Alzheimer's Disease. ACS Chem Neurosci 2022; 13:2503-2516. [PMID: 35926183 DOI: 10.1021/acschemneuro.2c00361] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The formation and accumulation of amyloid beta (Aβ) peptide are considered the crucial events that are responsible for the progression of Alzheimer's disease (AD). Herein, we have designed and synthesized a series of fluorescent probes by using electron acceptor-donor end groups interacting with a π-conjugating system for the detection of Aβ aggregates. The chemical structure of these probes denoted as RMs, having a conjugated π-system (C═C), showed a maximum emission in PBS (>600 nm), which is the best range for a fluorescent imaging probe. Among all these probes, RM-28 showed an excellent fluorescence property with an emission maximum of >598 nm upon binding to Aβ aggregates. RM-28 also showed high sensitivity (7.5-fold) and high affinities toward Aβ aggregates (Kd = 175.69 ± 4.8 nM; Ka = 0.5 × 107 M-1). It can cross the blood-brain barrier of mice efficiently. The affinity of RM-28 toward Aβ aggregates was observed in 3xTg-AD brain sections of the hippocampus and cortex region using a fluorescent imaging technique, as well as an in vitro fluorescence-based binding assay with Aβ aggregates. Moreover, RM-28 is highly specific to Aβ aggregates and does not bind with intracellular proteins like bovine serum albumin (BSA) and α-synuclein (α-Syn) aggregates. The results indicate that the probe RM-28 emerges as an efficient and veritable highly specific fluorescent probe for the detection of Aβ aggregates in both in vitro and in vivo model systems.
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Affiliation(s)
- Rathnam Mallesh
- Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India.,Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India.,National Institute of Pharmaceutical Education and Research, Kolkata, Chunilal Bhawan 168, Maniktala Main Road, Kolkata 700054, India
| | - Juhee Khan
- Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India.,Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India
| | - Krishnangsu Pradhan
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India
| | - Rajsekhar Roy
- Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India
| | - Nihar Ranjan Jana
- School of Bioscience, Indian Institute of Technology, Kharagpur 721302, India
| | - Parasuraman Jaisankar
- Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India
| | - Surajit Ghosh
- Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, NH 65, Surpura Bypass Road, Karwar, Rajasthan 342037, India.,Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India.,National Institute of Pharmaceutical Education and Research, Kolkata, Chunilal Bhawan 168, Maniktala Main Road, Kolkata 700054, India
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Liu XY, Wang XJ, Shi L, Liu YH, Wang L, Li K, Bu Q, Cen XB, Yu XQ. Rational Design of Quinoxalinone-Based Red-Emitting Probes for High-Affinity and Long-Term Visualizing Amyloid-β In Vivo. Anal Chem 2022; 94:7665-7673. [PMID: 35578920 DOI: 10.1021/acs.analchem.2c01046] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease with insidious onset, and the deposition of amyloid-β (Aβ) is believed to be one of the main cause. Fluorescence imaging is a promising technique for this task, but the Aβ gold standard probe ThT developed based on this still has shortcomings. The development of a new fluorescent probe to detect Aβ plaques is thought to be essential. Herein, a series of red to near-infrared emitting fluorescent probes QNO-ADs with newly quinoxalinone skeleton are designed to detect Aβ plaques. They all demonstrate excellent optical properties and high binding affinity (∼Kd = 20 nM) to Aβ aggregates. As the most outstanding candidate, QNO-AD-3 shows significant signal-to-noise (S/N) ratio at the level of in vitro binding studies, and the brilliant fluorescence staining results in favor of grasping the approximate distribution of Aβ plaques in the brain slice. In vivo Aβ plaques imaging suggests that QNO-AD-3 can cross the BBB and have a long retention time in the brain with low biological toxicity. In addition, the results of docking theoretical calculation also provide some references for the design of Aβ probe. Overall, given the high affinity of QNO-AD-3 and the ability to monitor Aβ plaques for a long time that is not common now, we believe QNO-AD-3 will be an effective tool for an Aβ-related matrix and AD disease research in the future.
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Affiliation(s)
- Xin-Yao Liu
- Key Laboratory of Green Chemistry and Technology (Ministry of Education), College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Xiao-Jie Wang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Lei Shi
- Key Laboratory of Green Chemistry and Technology (Ministry of Education), College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.,State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, People's Republic of China
| | - Yan-Hong Liu
- Key Laboratory of Green Chemistry and Technology (Ministry of Education), College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Liang Wang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Kun Li
- Key Laboratory of Green Chemistry and Technology (Ministry of Education), College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Qian Bu
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Xiao-Bo Cen
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Xiao-Qi Yu
- Key Laboratory of Green Chemistry and Technology (Ministry of Education), College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.,Department of Chemistry, Xihua University, Chengdu 610039, People's Republic of China
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5
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Wu J, Shao C, Ye X, Di X, Li D, Zhao H, Zhang B, Chen G, Liu HK, Qian Y. In Vivo Brain Imaging of Amyloid-β Aggregates in Alzheimer's Disease with a Near-Infrared Fluorescent Probe. ACS Sens 2021; 6:863-870. [PMID: 33438997 DOI: 10.1021/acssensors.0c01914] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Abnormal accumulation of amyloid-β (Aβ) has been determined to be a critical factor for the progression of Alzheimer's disease (AD), which has motivated the development of new chemical approaches for early sensing and imaging of these Aβ aggregates. Herein, we report a new near-infrared (NIR) fluorescent probe for the selective monitoring of Aβ aggregates in vivo. This novel fluorophore, named CAQ, was based on the curcumin scaffold and was designed by introducing an intramolecular rotation donor and a quinoline functional group. CAQ was an environment-sensitive fluorescent probe that can be used as a reliable chemical tool for NIR imaging of amyloid plaques in a live Caenorhabditis elegans model of AD and in 5× FAD transgenic mice of early amyloid deposition. Our observations indicate that CAQ is promising for providing comprehensive information on neurodegenerative research, thereby promoting a deeper understanding of Alzheimer's pathological processes.
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Affiliation(s)
- Jian Wu
- School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road 1, Nanjing 210046, China
| | - Chenwen Shao
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, China
| | - Xiaolian Ye
- State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, 12 Xuefu Avenue, Nanjing 210061, China
| | - Xiaojiao Di
- School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road 1, Nanjing 210046, China
| | - Dongdong Li
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Hu Zhao
- School of Pharmaceutical Science, Zhejiang Chinese Medicine University, Hangzhou 311402, China
| | - Bing Zhang
- Department of Radiology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China
| | - Guiquan Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, 12 Xuefu Avenue, Nanjing 210061, China
| | - Hong-Ke Liu
- School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road 1, Nanjing 210046, China
| | - Yong Qian
- School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road 1, Nanjing 210046, China
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6
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Oliveira AC, Costa T, Justino LLG, Fausto R, Morfin JF, Tóth É, Geraldes CFGC, Burrows HD. Photophysical studies on lanthanide(III) chelates conjugated to Pittsburgh compound B as luminescent probes targeted to Aβ amyloid aggregates. Photochem Photobiol Sci 2020; 19:1522-1537. [PMID: 32966544 DOI: 10.1039/d0pp00214c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The photophysical properties of Eu3+ and Tb3+ complexes of DOTAGA and DO3A-monoamide conjugates of the Pittsburgh compound B (PiB) chromophore, prepared using linkers of different lengths and flexibilities, and which form stable negatively charged (LnL1), and uncharged (LnL2) complexes, respectively, were studied as potential probes for optical detection of amyloid aggregates. The phenylbenzothiazole (PiB) moiety absorbs light at wavelengths longer than 330 nm with a high molar absorption coefficient in both probes, and acts as an antenna in these systems. The presence of the luminescent Ln3+ ion quenches the excited states of PiB through an energy transfer process from the triplet state of PiB to the metal centre, and structured emission is seen from Eu3+ and Tb3+. The luminescence study indicates the presence of a 5D4 → T1 back transfer process in the Tb3+ complexes. It also provides insights on structural properties of the Eu3+ complexes, such as the high symmetry environment of the Eu3+ ion in a single macrocyclic conformation and the presence of one water molecule in its inner coordination sphere. The overall quantum yield of luminescence of EuL1 is higher than for EuL2. However, their low values reflect the low overall sensitization efficiency of the energy transfer process, which is a consequence of the large distances between the metal center and the antenna, especially in the EuL2 complex. DFT calculations confirmed that the most stable conformation of the Eu3+ complexes involves a combination of a square antiprismatic (SAP) geometry of the chelate and an extended conformation of the linker. The large calculated average distances between the metal center and the antenna point to the predominance of the Förster energy transfer mechanism, especially for EuL2. This study provides insights into the behavior of amyloid-targeted Ln3+ complexes as optical probes, and contributes towards their rational design.
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Affiliation(s)
- Alexandre C Oliveira
- University of Coimbra, Coimbra Chemistry Centre (CQC), Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - Telma Costa
- University of Coimbra, Coimbra Chemistry Centre (CQC), Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - Licinia L G Justino
- University of Coimbra, Coimbra Chemistry Centre (CQC), Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - Rui Fausto
- University of Coimbra, Coimbra Chemistry Centre (CQC), Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - Jean-François Morfin
- Centre de Biophysique Moléculaire, CNRS, UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France
| | - Éva Tóth
- Centre de Biophysique Moléculaire, CNRS, UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France
| | - Carlos F G C Geraldes
- University of Coimbra, Coimbra Chemistry Centre (CQC), Department of Chemistry, 3004-535 Coimbra, Portugal. and University of Coimbra, Department of Life Sciences, Calçada Martim de Freitas, 3000-393 Coimbra, Portugal. and CIBIT/ICNAS - Instituto de Ciências Nucleares Aplicadas à Saúde, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Hugh D Burrows
- University of Coimbra, Coimbra Chemistry Centre (CQC), Department of Chemistry, 3004-535 Coimbra, Portugal.
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Zaghmi A, Drouin-Ouellet J, Brambilla D, Gauthier MA. Treating brain diseases using systemic parenterally-administered protein therapeutics: Dysfunction of the brain barriers and potential strategies. Biomaterials 2020; 269:120461. [PMID: 33218788 DOI: 10.1016/j.biomaterials.2020.120461] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 09/23/2020] [Accepted: 10/18/2020] [Indexed: 12/12/2022]
Abstract
The parenteral administration of protein therapeutics is increasingly gaining importance for the treatment of human diseases. However, the presence of practically impermeable blood-brain barriers greatly restricts access of such pharmaceutics to the brain. Treating brain disorders with proteins thus remains a great challenge, and the slow clinical translation of these therapeutics may be largely ascribed to the lack of appropriate brain delivery system. Exploring new approaches to deliver proteins to the brain by circumventing physiological barriers is thus of great interest. Moreover, parallel advances in the molecular neurosciences are important for better characterizing blood-brain interfaces, particularly under different pathological conditions (e.g., stroke, multiple sclerosis, Parkinson's disease, and Alzheimer's disease). This review presents the current state of knowledge of the structure and the function of the main physiological barriers of the brain, the mechanisms of transport across these interfaces, as well as alterations to these concomitant with brain disorders. Further, the different strategies to promote protein delivery into the brain are presented, including the use of molecular Trojan horses, the formulation of nanosystems conjugated/loaded with proteins, protein-engineering technologies, the conjugation of proteins to polymers, and the modulation of intercellular junctions. Additionally, therapeutic approaches for brain diseases that do not involve targeting to the brain are presented (i.e., sink and scavenging mechanisms).
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Affiliation(s)
- A Zaghmi
- Institut National de la Recherche Scientifique (INRS), EMT Research Center, Varennes, QC, J3X 1S2, Canada
| | - J Drouin-Ouellet
- Faculty of Pharmacy, Université de Montréal, CP 6128, succ. Centre-ville, Montréal, QC, H3C 3J7, Canada
| | - D Brambilla
- Faculty of Pharmacy, Université de Montréal, CP 6128, succ. Centre-ville, Montréal, QC, H3C 3J7, Canada
| | - M A Gauthier
- Institut National de la Recherche Scientifique (INRS), EMT Research Center, Varennes, QC, J3X 1S2, Canada.
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8
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Kaur A, New EJ, Sunde M. Strategies for the Molecular Imaging of Amyloid and the Value of a Multimodal Approach. ACS Sens 2020; 5:2268-2282. [PMID: 32627533 DOI: 10.1021/acssensors.0c01101] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Protein aggregation has been widely implicated in neurodegenerative diseases such as Alzheimer's disease, frontotemporal dementia, Parkinson's disease, and Huntington disease, as well as in systemic amyloidoses and conditions associated with localized amyloid deposits, such as type-II diabetes. The pressing need for a better understanding of the factors governing protein assembly has driven research for the development of molecular sensors for amyloidogenic proteins. To date, a number of sensors have been developed that report on the presence of protein aggregates utilizing various modalities, and their utility demonstrated for imaging protein aggregation in vitro and in vivo. Analysis of these sensors highlights the various advantages and disadvantages of the different imaging modalities and makes clear that multimodal sensors with properties amenable to more than one imaging technique need to be developed. This critical review highlights the key molecular scaffolds reported for molecular imaging modalities such as fluorescence, positron emission tomography, single photon emission computed tomography, and magnetic resonance imaging and includes discussion of the advantages and disadvantages of each modality, and future directions for the design of amyloid sensors. We also discuss the recent efforts focused on the design and development of multimodal sensors and the value of cross-validation across multiple modalities.
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Affiliation(s)
- Amandeep Kaur
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, New South Wales 2006, Australia
- The University of Sydney, Nano Institute (Sydney Nano), The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Elizabeth J. New
- The University of Sydney, Nano Institute (Sydney Nano), The University of Sydney, Sydney, New South Wales 2006, Australia
- The University of Sydney, School of Chemistry, Faculty of Science, Sydney, New South Wales 2006, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Margaret Sunde
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, New South Wales 2006, Australia
- The University of Sydney, Nano Institute (Sydney Nano), The University of Sydney, Sydney, New South Wales 2006, Australia
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9
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Jokar S, Behnammanesh H, Erfani M, Sharifzadeh M, Gholami M, Sabzevari O, Amini M, Geramifar P, Hajiramezanali M, Beiki D. Synthesis, biological evaluation and preclinical study of a novel 99mTc-peptide: A targeting probe of amyloid-β plaques as a possible diagnostic agent for Alzheimer's disease. Bioorg Chem 2020; 99:103857. [PMID: 32330736 DOI: 10.1016/j.bioorg.2020.103857] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 01/01/2023]
Abstract
With respect to the main role of amyloid-β (Aβ) plaques as one of the pathological hallmarks in the brain of Alzheimer's patients, the development of new imaging probes for targeted detection of Aβ plaques has attracted considerable interests. In this study, a novel cyclopentadienyl tricarbonyl Technetium-99 m (99mTc) agent with peptide scaffold, 99mTc-Cp-GABA-D-(FPLIAIMA)-NH2, for binding to the Aβ plaques was designed and successfully synthesized using the Fmoc solid-phase peptide synthesis method. This radiopeptide revealed a good affinity for Aβ42 aggregations (Kd = 20 µM) in binding affinity study and this result was confirmed by binding to Aβ plaques in brain sections of human Alzheimer's disease (AD) and rat models using in vitro autoradiography, fluorescent staining, and planar scintigraphy. Biodistribution studies of radiopeptide in AD and normal rats demonstrated a moderate initial brain uptake about 0.38 and 0.35% (ID/g) 2 min post-injection, respectively. Whereas, AD rats showed a notable retention time in the brain (0.23% ID/g at 30 min) in comparison with fast clearance in normal rat brains. Normal rats following treatment with cyclosporine A as a p-glycoprotein inhibitor showed a significant increase in the radiopeptide brain accumulation compared to non-treated ones. There was a good correlation between data gathered from single-photon emission computed tomography/computed tomography (SPECT/CT) imaging and biodistribution studies. Therefore, these findings showed that this novel radiopeptide could be a potential SPECT imaging agent for early detection of Aβ plaques in the brain of patients with AD.
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Affiliation(s)
- Safura Jokar
- Department of Nuclear Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Behnammanesh
- Department of Nuclear Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mostafa Erfani
- Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran.
| | - Mohammad Sharifzadeh
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran; Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran
| | - Mahdi Gholami
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran; Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran
| | - Omid Sabzevari
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran; Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohsen Amini
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; Drug Design and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Parham Geramifar
- Research Center for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Maliheh Hajiramezanali
- Department of Nuclear Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Davood Beiki
- Research Center for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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10
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Multifunctional imaging of amyloid-beta peptides with a new gadolinium-based contrast agent in Alzheimer’s disease. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2019.11.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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11
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Lacerda S, Morfin JF, Geraldes CFGC, Tóth É. Metal complexes for multimodal imaging of misfolded protein-related diseases. Dalton Trans 2017; 46:14461-14474. [DOI: 10.1039/c7dt02371e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aggregation of misfolded proteins and progressive polymerization of otherwise soluble proteins is a common hallmark of several highly debilitating and increasingly prevalent diseases, including amyotrophic lateral sclerosis, cerebral amyloid angiopathy, type II diabetes and Parkinson's, Huntington's and Alzheimer's diseases.
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Affiliation(s)
- S. Lacerda
- Centre de Biophysique Moléculaire
- CNRS
- UPR 4301
- Université d'Orléans
- 45071 Orléans Cedex 2
| | - J.-F. Morfin
- Centre de Biophysique Moléculaire
- CNRS
- UPR 4301
- Université d'Orléans
- 45071 Orléans Cedex 2
| | - C. F. G. C. Geraldes
- Department of Life Sciences
- Faculty of Sciences and Technology
- University of Coimbra
- 3000-393 Coimbra
- Portugal
| | - É. Tóth
- Centre de Biophysique Moléculaire
- CNRS
- UPR 4301
- Université d'Orléans
- 45071 Orléans Cedex 2
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12
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Salerno M, Santo Domingo Porqueras D. Alzheimer's disease: The use of contrast agents for magnetic resonance imaging to detect amyloid beta peptide inside the brain. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.04.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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13
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Rajasekhar K, Narayanaswamy N, Murugan NA, Kuang G, Ågren H, Govindaraju T. A High Affinity Red Fluorescence and Colorimetric Probe for Amyloid β Aggregates. Sci Rep 2016; 6:23668. [PMID: 27032526 PMCID: PMC4817056 DOI: 10.1038/srep23668] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 03/07/2016] [Indexed: 01/28/2023] Open
Abstract
A major challenge in the Alzheimer's disease (AD) is its timely diagnosis. Amyloid β (Aβ) aggregates have been proposed as the most viable biomarker for the diagnosis of AD. Here, we demonstrate hemicyanine-based benzothiazole-coumarin (TC) as a potential probe for the detection of highly toxic Aβ42 aggregates through switch-on, enhanced (~30 fold) red fluorescence (Emax = 654 nm) and characteristic colorimetric (light red to purple) optical outputs. Interestingly, TC exhibits selectivity towards Aβ42 fibrils compared to other abnormal protein aggregates. TC probe show nanomolar binding affinity (Ka = 1.72 × 10(7) M(-1)) towards Aβ42 aggregates and also displace ThT bound to Aβ42 fibrils due to its high binding affinity. The Aβ42 fibril-specific red-shift in the absorption spectra of TC responsible for the observed colorimetric optical output has been attributed to micro-environment change around the probe from hydrophilic-like to hydrophobic-like nature. The binding site, binding energy and changes in optical properties observed for TC upon interaction with Aβ42 fibrils have been further validated by molecular docking and time dependent density functional theory studies.
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Affiliation(s)
- K. Rajasekhar
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bengaluru 560064, Karnataka, India
| | - Nagarjun Narayanaswamy
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bengaluru 560064, Karnataka, India
| | - N. Arul Murugan
- Division of Theoretical Chemistry and Biology, School of Biotechnology, KTH Royal Institute of Technology, S-106 91 Stockholm, Sweden
| | - Guanglin Kuang
- Division of Theoretical Chemistry and Biology, School of Biotechnology, KTH Royal Institute of Technology, S-106 91 Stockholm, Sweden
| | - Hans Ågren
- Division of Theoretical Chemistry and Biology, School of Biotechnology, KTH Royal Institute of Technology, S-106 91 Stockholm, Sweden
| | - T. Govindaraju
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bengaluru 560064, Karnataka, India
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14
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Associating a negatively charged GdDOTA-derivative to the Pittsburgh compound B for targeting Aβ amyloid aggregates. J Biol Inorg Chem 2015; 21:83-99. [DOI: 10.1007/s00775-015-1316-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 11/13/2015] [Indexed: 01/26/2023]
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15
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Tu P, Fu H, Cui M. Compounds for imaging amyloid-β deposits in an Alzheimer's brain: a patent review. Expert Opin Ther Pat 2015; 25:413-23. [PMID: 25746836 DOI: 10.1517/13543776.2015.1007953] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
INTRODUCTION β-amyloid (Aβ) plaques in the brain are regarded as a hallmark of Alzheimer's disease (AD), and the imaging of Aβ is a critical step for early diagnosis. Extensive research has been done to develop probes for targeting Aβ with available imaging modalities. AREAS COVERED In this review, the authors give an overview of published patents and papers about the discovery and development of compounds possessing potential utilization in imaging Aβ for the diagnosis of AD. SciFinder is the main electronic database for patent study in this review. EXPERT OPINION Despite achievements in Aβ imaging, there is still a need to develop innovative compounds with selectivity and high affinity to Aβ. Positron emission tomography imaging agents will still be the trend in the field in the short term. Due to the low costs for single-photon emission computed tomography (SPECT) and the excellent nuclear properties of (99m)Tc, substantial research should be conducted on the development of the probes for SPECT. Refining the current imaging techniques and in the meantime developing new efficient imaging multimodality and compounds would be a promising approach to imaging Aβ.
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Affiliation(s)
- Peiyu Tu
- Beijing Normal University, College of Chemistry, Key Laboratory of Radiopharmaceuticals, Ministry of Education , Beijing 100875 , P.R. China +86 10 58808891 ; +86 10 58808891 ;
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16
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Zhang D, Fa HB, Zhou JT, Li S, Diao XW, Yin W. The detection of β-amyloid plaques in an Alzheimer's disease rat model with DDNP-SPIO. Clin Radiol 2015; 70:74-80. [DOI: 10.1016/j.crad.2014.09.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 09/24/2014] [Accepted: 09/25/2014] [Indexed: 01/20/2023]
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17
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Gadolinium-based contrast agents targeted to amyloid aggregates for the early diagnosis of Alzheimer's disease by MRI. Eur J Med Chem 2014; 87:843-61. [PMID: 25440885 DOI: 10.1016/j.ejmech.2014.10.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 09/16/2014] [Accepted: 10/07/2014] [Indexed: 12/14/2022]
Abstract
While important efforts were made in the development of positron emission tomography (PET) tracers for the in vivo molecular diagnosis of Alzheimer's disease, very few investigations to develop magnetic resonance imaging (MRI) probes were performed. Here, a new generation of Gd(III)-based contrast agents (CAs) is proposed to detect the amyloid β-protein (Aβ) aggregates by MRI, one of the earliest biological hallmarks of the pathology. A building block strategy was used to synthesize a library of 16 CAs to investigate structure-activity relationships (SARs) on physicochemical properties and binding affinity for the Aβ aggregates. Three types of blocks were used to modulate the CA structures: (i) the Gd(III) chelates (Gd(III)-DOTA and Gd(III)-PCTA), (ii) the biovectors (2-arylbenzothiazole, 2-arylbenzoxazole and stilbene derivatives) and (iii) the linkers (neutrals, positives and negatives with several lengths). These investigations revealed unexpected SARs and a difficulty of these probes to cross the blood-brain barrier (BBB). General insights for the development of Gd(III)-based CAs to detect the Aβ aggregates are described.
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Ansciaux E, Burtea C, Laurent S, Crombez D, Nonclercq D, Vander Elst L, Muller RN. In vitro and in vivo characterization of several functionalized ultrasmall particles of iron oxide, vectorized against amyloid plaques and potentially able to cross the blood-brain barrier: toward earlier diagnosis of Alzheimer's disease by molecular imag. CONTRAST MEDIA & MOLECULAR IMAGING 2014; 10:211-24. [DOI: 10.1002/cmmi.1626] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 07/13/2014] [Accepted: 08/25/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Emilie Ansciaux
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory; University of Mons; Avenue Maistriau 19, Mendeleev Building B-7000 Mons Belgium
| | - Carmen Burtea
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory; University of Mons; Avenue Maistriau 19, Mendeleev Building B-7000 Mons Belgium
| | - Sophie Laurent
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory; University of Mons; Avenue Maistriau 19, Mendeleev Building B-7000 Mons Belgium
| | - Deborah Crombez
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory; University of Mons; Avenue Maistriau 19, Mendeleev Building B-7000 Mons Belgium
| | - Denis Nonclercq
- Laboratory of Histology; University of Mons; Pentagon - 1B, 6 Avenue du Champ de Mars B-7000 Mons Belgium
| | - Luce Vander Elst
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory; University of Mons; Avenue Maistriau 19, Mendeleev Building B-7000 Mons Belgium
| | - Robert N. Muller
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory; University of Mons; Avenue Maistriau 19, Mendeleev Building B-7000 Mons Belgium
- Center for Microscopy and Molecular Imaging; 8, rue Adrienne Bolland 6041 Gosselies Belgium
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19
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Agile delivery of protein therapeutics to CNS. J Control Release 2014; 190:637-63. [PMID: 24956489 DOI: 10.1016/j.jconrel.2014.06.017] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 06/10/2014] [Accepted: 06/13/2014] [Indexed: 12/11/2022]
Abstract
A variety of therapeutic proteins have shown potential to treat central nervous system (CNS) disorders. Challenge to deliver these protein molecules to the brain is well known. Proteins administered through parenteral routes are often excluded from the brain because of their poor bioavailability and the existence of the blood-brain barrier (BBB). Barriers also exist to proteins administered through non-parenteral routes that bypass the BBB. Several strategies have shown promise in delivering proteins to the brain. This review, first, describes the physiology and pathology of the BBB that underscore the rationale and needs of each strategy to be applied. Second, major classes of protein therapeutics along with some key factors that affect their delivery outcomes are presented. Third, different routes of protein administration (parenteral, central intracerebroventricular and intraparenchymal, intranasal and intrathecal) are discussed along with key barriers to CNS delivery associated with each route. Finally, current delivery strategies involving chemical modification of proteins and use of particle-based carriers are overviewed using examples from literature and our own work. Whereas most of these studies are in the early stage, some provide proof of mechanism of increased protein delivery to the brain in relevant models of CNS diseases, while in few cases proof of concept had been attained in clinical studies. This review will be useful to broad audience of students, academicians and industry professionals who consider critical issues of protein delivery to the brain and aim developing and studying effective brain delivery systems for protein therapeutics.
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Martins AF, Morfin JF, Geraldes CFGC, Tóth É. Gd3+ complexes conjugated to Pittsburgh compound B: potential MRI markers of β-amyloid plaques. J Biol Inorg Chem 2013; 19:281-95. [DOI: 10.1007/s00775-013-1055-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/09/2013] [Indexed: 11/29/2022]
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21
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Sillerud LO, Solberg NO, Chamberlain R, Orlando RA, Heidrich JE, Brown DC, Brady CI, Vander Jagt TA, Garwood M, Vander Jagt DL. SPION-enhanced magnetic resonance imaging of Alzheimer's disease plaques in AβPP/PS-1 transgenic mouse brain. J Alzheimers Dis 2013; 34:349-65. [PMID: 23229079 DOI: 10.3233/jad-121171] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In our program to develop non-invasive magnetic resonance imaging (MRI) methods for the diagnosis of Alzheimer's disease (AD), we have synthesized antibody-conjugated, superparamagnetic iron oxide nanoparticles (SPIONs) for use as an in vivo agent for MRI detection of amyloid-β plaques in AD. Here we report studies in AβPP/PS1 transgenic mice, which demonstrate the ability of novel anti-AβPP conjugated SPIONs to penetrate the blood-brain barrier to act as a contrast agent for MR imaging of plaques. The conspicuity of the plaques increased from an average Z-score of 5.1 ± 0.5 to 8.3 ± 0.2 when the plaque contrast to noise ratio was compared in control AD mice with AD mice treated with SPIONs. The number of MRI-visible plaques per brain increased from 347 ± 45 in the control AD mice, to 668 ± 86 in the SPION treated mice. These results indicated that our SPION enhanced amyloid-β detection method delivers an efficacious, non-invasive MRI detection method in transgenic mice.
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Affiliation(s)
- Laurel O Sillerud
- Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA.
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22
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Vithanarachchi SM, Allen MJ. A multimodal, β-amyloid-targeted contrast agent. Chem Commun (Camb) 2013; 49:4148-50. [DOI: 10.1039/c2cc36583a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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23
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Vithanarachchi SM, Allen MJ. Strategies for Target-Specific Contrast Agents for Magnetic Resonance Imaging. ACTA ACUST UNITED AC 2012; 1:12-25. [PMID: 23316452 DOI: 10.2174/2211555211201010012] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review describes recent research efforts focused on increasing the specificity of contrast agents for proton magnetic resonance imaging (MRI). Contrast agents play an indispensable role in MRI by enhancing the inherent contrast of images; however, the non-specific nature of current clinical contrast agents limits their usefulness. This limitation can be addressed by conjugating contrast agents or contrast-agent-loaded carriers-including polymers, nanoparticles, dendrimers, and liposomes-to molecules that bind to biological sites of interest. An alternative approach to conjugation is synthetically mimicking biological structures with metal complexes that are also contrast agents. In this review, we describe the advantages and limitations of these two targeting strategies with respect to translation from in vitro to in vivo imaging while focusing on advances from the last ten years.
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Liu K, Guo TL, Chojnacki J, Lee HG, Wang X, Siedlak SL, Rao W, Zhu X, Zhang S. Bivalent ligand containing curcumin and cholesterol as fluorescence probe for Aβ plaques in Alzheimer's disease. ACS Chem Neurosci 2012; 3:141-146. [PMID: 22685625 DOI: 10.1021/cn200122j] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A recently developed bivalent ligand BMAOI 14 (7) has been evaluated for its capability to label and detect aggregated β-amyloid (Aβ) peptide as a fluorescent probe. This probe contains curcumin as the Aβ recognition moiety and cholesterol as an anchorage to the neuronal cell membrane/lipid rafts. The results demonstrate that 7 binds to the monomers, oligomers as well as fibrils of Aβ42 with low micromolar to submicromolar binding affinities. This chemical probe also has many of the required optical properties for use in imaging and can rapidly cross the blood-brain barrier (BBB) in vivo. Furthermore, 7 specifically binds to Aβ plaques in both AD human patients and APP transgenic mouse brain tissues. Collectively, these results suggest that 7 is a strong candidate as an Aβ-imaging agent and encourage further optimization of 7 as a new lead to develop the next generation of Aβ-imaging probes.
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Affiliation(s)
- Kai Liu
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | - Tai L. Guo
- Department
of Pharmacology and
Toxicology, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Jeremy Chojnacki
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | - Hyoung-Gon Lee
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Xinglong Wang
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Sandra L. Siedlak
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Wei Rao
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Shijun Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
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25
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Abstract
Neuroimaging allows researchers and clinicians to noninvasively assess structure and function of the brain. With the advances of imaging modalities such as magnetic resonance, nuclear, and optical imaging; the design of target-specific probes; and/or the introduction of reporter gene assays, these technologies are now capable of visualizing cellular and molecular processes in vivo. Undoubtedly, the system biological character of molecular neuroimaging, which allows for the study of molecular events in the intact organism, will enhance our understanding of physiology and pathophysiology of the brain and improve our ability to diagnose and treat diseases more specifically. Technical/scientific challenges to be faced are the development of highly sensitive imaging modalities, the design of specific imaging probe molecules capable of penetrating the CNS and reporting on endogenous cellular and molecular processes, and the development of tools for extracting quantitative, biologically relevant information from imaging data. Today, molecular neuroimaging is still an experimental approach with limited clinical impact; this is expected to change within the next decade. This article provides an overview of molecular neuroimaging approaches with a focus on rodent studies documenting the exploratory state of the field. Concepts are illustrated by discussing applications related to the pathophysiology of Alzheimer's disease.
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Affiliation(s)
- Jan Klohs
- Institute for Biomedical Engineering, ETH & University of Zürich, Switzerland
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26
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Yang CT, Chuang KH. Gd(iii) chelates for MRI contrast agents: from high relaxivity to “smart”, from blood pool to blood–brain barrier permeable. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md00279e] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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McLean D, Cooke MJ, Wang Y, Fraser P, St George-Hyslop P, Shoichet MS. Targeting the amyloid-β antibody in the brain tissue of a mouse model of Alzheimer's disease. J Control Release 2011; 159:302-8. [PMID: 22245684 DOI: 10.1016/j.jconrel.2011.12.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 12/16/2011] [Accepted: 12/25/2011] [Indexed: 11/28/2022]
Abstract
Alzheimer's disease is a neurodegenerative disease characterized pathologically by amyloid-β (Aβ) aggregates in the brain. Notwithstanding many promising therapeutics that are under development, early diagnosis of Alzheimer's disease is limited. By targeting the Aβ aggregates, diagnosis can be improved and disease progression reduced. Molecular imaging using monoclonal antibodies to target specific isoforms of Aβ aggregates offer increased specificity in comparison to conventional imaging tracers; however, antibodies that are widely used in histology do not necessarily show similar binding in a dynamic in vivo environment. In this study, the diffusion and binding were studied of a classical monoclonal antibody, 6E10, in the brain of the TgCRND8 mouse model of AD. After intracranial injection of fluorescent 6E10, we observed broad and rapid labelling of Aβ deposits in the cortex and corpus callosum within 4h. Aβ plaques were detected up to 2.5mm away from the injection site in TgCRND8 mice and not in wild type mice at all, demonstrating specificity of binding. The apparent diffusivity and elimination constant of the anti-Aβ antibody were found to be independent of both the age of the animal and the accumulation of Aβ in the extracellular space, suggesting broad applicability of this targeting molecule. Mathematical modelling of the diffusion profiles of the anti-Aβ antibody in the brain parenchyma provides insights into the utility of antibodies as molecular imaging tools and targeted therapeutics.
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Affiliation(s)
- Daniel McLean
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
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Sarkar G, Curran GL, Mahlum E, Decklever T, Wengenack TM, Blahnik A, Hoesley B, Lowe VJ, Poduslo JF, Jenkins RB. A carrier for non-covalent delivery of functional beta-galactosidase and antibodies against amyloid plaques and IgM to the brain. PLoS One 2011; 6:e28881. [PMID: 22216132 PMCID: PMC3244419 DOI: 10.1371/journal.pone.0028881] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 11/16/2011] [Indexed: 11/18/2022] Open
Abstract
Background Therapeutic intervention of numerous brain-associated disorders currently remains unrealized due to serious limitations imposed by the blood-brain-barrier (BBB). The BBB generally allows transport of small molecules, typically <600 daltons with high octanol/water partition coefficients, but denies passage to most larger molecules. However, some receptors present on the BBB allow passage of cognate proteins to the brain. Utilizing such receptor-ligand systems, several investigators have developed methods for delivering proteins to the brain, a critical requirement of which involves covalent linking of the target protein to a carrier entity. Such covalent modifications involve extensive preparative and post-preparative chemistry that poses daunting limitations in the context of delivery to any organ. Here, we report creation of a 36-amino acid peptide transporter, which can transport a protein to the brain after routine intravenous injection of the transporter-protein mixture. No covalent linkage of the protein with the transporter is necessary. Approach A peptide transporter comprising sixteen lysine residues and 20 amino acids corresponding to the LDLR-binding domain of apolipoprotein E (ApoE) was synthesized. Transport of beta-galactosidase, IgG, IgM, and antibodies against amyloid plques to the brain upon iv injection of the protein-transporter mixture was evaluated through staining for enzyme activity or micro single photon emission tomography (micro-SPECT) or immunostaining. Effect of the transporter on the integrity of the BBB was also investigated. Principal Findings The transporter enabled delivery to the mouse brain of functional beta-galactosidase, human IgG and IgM, and two antibodies that labeled brain-associated amyloid beta plaques in a mouse model of Alzheimer's disease. Significance The results suggest the transporter is able to transport most or all proteins to the brain without the need for chemically linking the transporter to a protein. Thus, the approach offers an avenue for rapid clinical evaluation of numerous candidate drugs against neurological diseases including cancer. (299 words).
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Affiliation(s)
- Gobinda Sarkar
- Department of Experimental Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (GS); (RJ)
| | - Geoffry L. Curran
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Eric Mahlum
- Department of Experimental Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Teresa Decklever
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Thomas M. Wengenack
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Anthony Blahnik
- Tissue and Cell Molecular Analysis Laboratory, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Bridget Hoesley
- Tissue and Cell Molecular Analysis Laboratory, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Val J. Lowe
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Joseph F. Poduslo
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Robert B. Jenkins
- Department of Experimental Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (GS); (RJ)
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29
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Abstract
A number of medical imaging techniques are used heavily in the provision of spatially resolved information on disease and physiological status and accordingly play a critical role in clinical diagnostics and subsequent treatment. Though, for most imaging modes, contrast is potentially enhanced through the use of contrast agents or improved hardware or imaging protocols, no single methodology provides, in isolation, a detailed mapping of anatomy, disease markers or physiological status. In recent years, the concept of complementing the strengths of one imaging modality with those of another has come to the fore and been further bolstered by the development of fused instruments such as PET/CT and PET/MRI stations. Coupled with the continual development in imaging hardware has been a surge in reports of contrast agents bearing multiple functionality, potentially providing not only a powerful and highly sensitised means of co-localising physiological/disease status and anatomy, but also the tracking and delineation of multiple markers and indeed subsequent or simultaneous highly localized therapy ("theragnostics").
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Affiliation(s)
- Wen-Yen Huang
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
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30
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Yanagisawa D, Amatsubo T, Morikawa S, Taguchi H, Urushitani M, Shirai N, Hirao K, Shiino A, Inubushi T, Tooyama I. In vivo detection of amyloid β deposition using 19F magnetic resonance imaging with a 19F-containing curcumin derivative in a mouse model of Alzheimer's disease. Neuroscience 2011; 184:120-7. [DOI: 10.1016/j.neuroscience.2011.03.071] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Revised: 03/01/2011] [Accepted: 03/29/2011] [Indexed: 10/18/2022]
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31
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Larbanoix L, Burtea C, Ansciaux E, Laurent S, Mahieu I, Vander Elst L, Muller RN. Design and evaluation of a 6-mer amyloid-beta protein derived phage display library for molecular targeting of amyloid plaques in Alzheimer's disease: Comparison with two cyclic heptapeptides derived from a randomized phage display library. Peptides 2011; 32:1232-43. [PMID: 21575663 DOI: 10.1016/j.peptides.2011.04.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2011] [Revised: 04/26/2011] [Accepted: 04/26/2011] [Indexed: 10/18/2022]
Abstract
Amyloid plaques are the main molecular hallmark of Alzheimer's disease. Specific carriers are needed for molecular imaging and for specific drug delivery. In order to identify new low molecular weight amyloid plaque-specific ligands, the phage display technology was used to design short peptides that bind specifically to amyloid-beta protein, which is the principal component of amyloid plaques. For this purpose, a phage display library was designed from the amino acid sequence of amyloid-beta 1-42. Then, the diversity was increased by soft oligonucleotide-directed mutagenesis. This library was screened against amyloid-beta 1-42 and several phage clones were isolated. Their genomes were sequenced to identify the displayed peptides and their dissociation constants for amyloid-beta 1-42 binding were evaluated by ELISA. The two best peptides, which are derived from the C-terminus hydrophobic domain of amyloid-beta 1-42 that forms a beta-strand in amyloid fibers, were synthesized and biotinylated. After confirming their binding affinity for amyloid-beta 1-42 by ELISA, the specific interaction with amyloid plaques was validated by immunohistochemistry on brain sections harvested from a mouse model of Alzheimer's disease. The thioflavin T aggregation assay has furthermore shown that our peptides are able to inhibit the amyloid fiber formation. They are not toxic for neurons, and some of them are able to cross the blood-brain barrier after grafting to a magnetic resonance imaging contrast agent. To conclude, these peptides have high potential for molecular targeting of amyloid plaques, either as carriers of molecular imaging and therapeutic compounds or as amyloid fiber disrupting agents.
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MESH Headings
- Alzheimer Disease/drug therapy
- Alzheimer Disease/genetics
- Alzheimer Disease/metabolism
- Alzheimer Disease/pathology
- Amino Acid Sequence
- Amyloid beta-Peptides/chemistry
- Amyloid beta-Peptides/genetics
- Amyloid beta-Peptides/metabolism
- Animals
- Benzothiazoles
- Biotinylation
- Blood-Brain Barrier/metabolism
- Blood-Brain Barrier/pathology
- Contrast Media
- Disease Models, Animal
- Enzyme-Linked Immunosorbent Assay
- Humans
- Kinetics
- Magnetic Resonance Imaging/methods
- Mice
- Mice, Transgenic
- Models, Molecular
- Molecular Sequence Data
- Molecular Targeted Therapy
- Mutagenesis, Site-Directed
- Peptide Fragments/chemistry
- Peptide Fragments/genetics
- Peptide Fragments/metabolism
- Peptide Fragments/pharmacology
- Peptide Library
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/genetics
- Peptides, Cyclic/metabolism
- Peptides, Cyclic/pharmacology
- Plaque, Amyloid/drug therapy
- Plaque, Amyloid/metabolism
- Plaque, Amyloid/pathology
- Protein Binding/drug effects
- Sequence Analysis, DNA
- Thiazoles/analysis
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Affiliation(s)
- Lionel Larbanoix
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory, University of Mons, Avenue Maistriau 19, B-7000 Mons, Belgium.
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Chang WM, Dakanali M, Capule CC, Sigurdson CJ, Yang J, Theodorakis EA. ANCA: A Family of Fluorescent Probes that Bind and Stain Amyloid Plaques in Human Tissue. ACS Chem Neurosci 2011; 2:249-255. [PMID: 21743829 DOI: 10.1021/cn200018v] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
A new family of fluorescent markers containing an Amino Naphthalenyl-2-Cyano-Acrylate (ANCA) motif has been synthesized and evaluated for its capability to associate with aggregated β-amyloid (Aβ) peptides. These fluorescent probes contain a nitrogen donor group that is connected via a naphthalene unit to an electron acceptor motif containing Water Solubilizing Groups (WSG). Chemical modifications were introduced to explore their effect on the capability of the ANCA-based probes to fluorescently label aggregated Aβ peptides. All synthesized probes bind to aggregated Aβ fibrils with low micromolar affinity and fluorescently stain amyloid deposits in human brain tissue from patients with Alzheimer's disease. We found that structural modifications of the WSG site do not affect considerably the binding affinity. However, changes of the nitrogen donor group alter significantly the binding affinity of these probes. Also, increasing the hydrophilicity of the donor group leads to improved contrast between the Aβ deposits and the surrounding tissue in histological staining experiments.
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Affiliation(s)
- Willy M. Chang
- Department of Chemistry & Biochemistry, University of California, San Diego, 9500 Gilman Drive MC: 0358, La Jolla, California 92093-0358, United States
| | - Marianna Dakanali
- Department of Chemistry & Biochemistry, University of California, San Diego, 9500 Gilman Drive MC: 0358, La Jolla, California 92093-0358, United States
| | - Christina C. Capule
- Department of Chemistry & Biochemistry, University of California, San Diego, 9500 Gilman Drive MC: 0358, La Jolla, California 92093-0358, United States
| | - Christina J. Sigurdson
- Department of Pathology, University of California, San Diego, 9500 Gilman Drive MC: 0612, La Jolla, 92093-0612, United States
| | - Jerry Yang
- Department of Chemistry & Biochemistry, University of California, San Diego, 9500 Gilman Drive MC: 0358, La Jolla, California 92093-0358, United States
| | - Emmanuel A. Theodorakis
- Department of Chemistry & Biochemistry, University of California, San Diego, 9500 Gilman Drive MC: 0358, La Jolla, California 92093-0358, United States
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Denic A, Macura SI, Mishra P, Gamez JD, Rodriguez M, Pirko I. MRI in rodent models of brain disorders. Neurotherapeutics 2011; 8:3-18. [PMID: 21274681 PMCID: PMC3075741 DOI: 10.1007/s13311-010-0002-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Magnetic resonance imaging (MRI) is a well-established tool in clinical practice and research on human neurological disorders. Translational MRI research utilizing rodent models of central nervous system (CNS) diseases is becoming popular with the increased availability of dedicated small animal MRI systems. Projects utilizing this technology typically fall into one of two categories: 1) true "pre-clinical" studies involving the use of MRI as a noninvasive disease monitoring tool which serves as a biomarker for selected aspects of the disease and 2) studies investigating the pathomechanism of known human MRI findings in CNS disease models. Most small animal MRI systems operate at 4.7-11.7 Tesla field strengths. Although the higher field strength clearly results in a higher signal-to-noise ratio, which enables higher resolution acquisition, a variety of artifacts and limitations related to the specific absorption rate represent significant challenges in these experiments. In addition to standard T1-, T2-, and T2*-weighted MRI methods, all of the currently available advanced MRI techniques have been utilized in experimental animals, including diffusion, perfusion, and susceptibility weighted imaging, functional magnetic resonance imaging, chemical shift imaging, heteronuclear imaging, and (1)H or (31)P MR spectroscopy. Selected MRI techniques are also exclusively utilized in experimental research, including manganese-enhanced MRI, and cell-specific/molecular imaging techniques utilizing negative contrast materials. In this review, we describe technical and practical aspects of small animal MRI and provide examples of different MRI techniques in anatomical imaging and tract tracing as well as several models of neurological disorders, including inflammatory, neurodegenerative, vascular, and traumatic brain and spinal cord injury models, and neoplastic diseases.
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Affiliation(s)
- Aleksandar Denic
- Department of Neuroscience, Mayo Clinic, Rochester, Minnesota 55905 USA
| | - Slobodan I. Macura
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905 USA
| | - Prasanna Mishra
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905 USA
| | - Jeffrey D. Gamez
- Department of Neurology, Mayo Clinic, 200 First St. SW, Rochester, Minnesota 55905 USA
| | - Moses Rodriguez
- Department of Neurology, Mayo Clinic, 200 First St. SW, Rochester, Minnesota 55905 USA
| | - Istvan Pirko
- Department of Neurology, Mayo Clinic, 200 First St. SW, Rochester, Minnesota 55905 USA
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34
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Larbanoix L, Burtea C, Laurent S, Van Leuven F, Toubeau G, Elst LV, Muller RN. Potential amyloid plaque-specific peptides for the diagnosis of Alzheimer's disease. Neurobiol Aging 2010; 31:1679-89. [DOI: 10.1016/j.neurobiolaging.2008.09.021] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 06/23/2008] [Accepted: 09/30/2008] [Indexed: 11/15/2022]
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35
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Jun HY, Yin HH, Kim SH, Park SH, Kim HS, Yoon KH. Visualization of tumor angiogenesis using MR imaging contrast agent Gd-DTPA-anti-VEGF receptor 2 antibody conjugate in a mouse tumor model. Korean J Radiol 2010; 11:449-56. [PMID: 20592929 PMCID: PMC2893316 DOI: 10.3348/kjr.2010.11.4.449] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Accepted: 02/22/2010] [Indexed: 11/23/2022] Open
Abstract
Objective To visualize tumor angiogenesis using the MRI contrast agent, Gd-DTPA-anti-VEGF receptor 2 antibody conjugate, with a 4.7-Tesla MRI instrument in a mouse model. Materials and Methods We designed a tumor angiogenesis-targeting T1 contrast agent that was prepared by the bioconjugation of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) and an anti-vascular endothelial growth factor receptor-2 (VEGFR2) antibody. The specific binding of the agent complex to cells that express VEGFR2 was examined in cultured murine endothelial cells (MS-1 cells) with a 4.7-Tesla magnetic resonance imaging scanner. Angiogenesis-specific T1 enhancement was imaged with the Gd-DTPA-anti-VEGFR2 antibody conjugate using a CT-26 adenocarcinoma tumor model in eight mice. As a control, the use of the Gd-DTPA-anti-rat immunoglobulin G (Gd-DTPA-anti-rat IgG) was imaged with a tumor model in eight mice. Statistical significance was assessed using the Mann-Whitney test. Tumor tissue was examined by immunohistochemical analysis. Results The Gd-DTPA-anti-VEGFR2 antibody conjugate showed predominant binding to cultured endothelial cells that expressed a high level of VEGFR2. Signal enhancement was approximately three-fold for in vivo T1-weighted MR imaging with the use of the Gd-DTPA-anti-VEGFR2 antibody conjugate as compared with the Gd-DTPA-rat IgG in the mouse tumor model (p < 0.05). VEGFR2 expression in CT-26 tumor vessels was demonstrated using immunohistochemical staining. Conclusion MR imaging using the Gd-DTPA-anti-VEGFR2 antibody conjugate as a contrast agent is useful in visualizing noninvasively tumor angiogenesis in a murine tumor model.
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Affiliation(s)
- Hong Young Jun
- Institute for Radiological Imaging Science, Wonkwang University School of Medicine, Jeonbuk 570-711, Korea
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36
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Vernon AC, Ballard C, Modo M. Neuroimaging for Lewy body disease: is the in vivo molecular imaging of α-synuclein neuropathology required and feasible? ACTA ACUST UNITED AC 2010; 65:28-55. [PMID: 20685363 DOI: 10.1016/j.brainresrev.2010.05.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 05/26/2010] [Accepted: 05/26/2010] [Indexed: 12/21/2022]
Abstract
Alpha-synuclein aggregation is a neuropathological hallmark of many neurodegenerative diseases including Parkinson's disease (PD), Parkinson's disease with dementia (PDD) and dementia with Lewy bodies (DLB), collectively termed the α-synucleinopathies. Substantial advances in clinical criteria and neuroimaging technology over the last 20 years have allowed great strides in the detection and differential diagnosis of these disorders. Nevertheless, it is clear that whilst the array of different imaging modalities in clinical use allow for a robust diagnosis of α-synucleinopathy in comparison to healthy subjects, there is no clear diagnostic imaging marker that affords a reliable differential diagnosis between the different forms of Lewy body disease (LBD) or that could facilitate tracking of disease progression. This has led to a call for a biomarker based on the pathological hallmarks of these diseases, namely α-synuclein-positive Lewy bodies (LBs). This potentially may be advantageous in terms of early disease detection, but may also be leveraged into a potential marker of disease progression. We here aim to firstly review the current status of neuroimaging biomarkers in PD and related synucleinopathies. Secondly, we outline the rationale behind α-synuclein imaging as a potential novel biomarker as well as the potential benefits and limitations of this approach. Thirdly, we attempt to illustrate the likely technical hurdles to be overcome to permit successful in vivo imaging of α-synuclein pathology in the diseased brain. Our overriding aim is to provide a framework for discussion of how to address this major unmet clinical need.
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Affiliation(s)
- Anthony C Vernon
- Kings College London, Institute of Psychiatry, Department of Neuroscience, Denmark Hill campus, London, UK
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37
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Craig TA, Sommer SL, Beito TG, Kumar R. Production and characterization of monoclonal antibodies to human sclerostin. Hybridoma (Larchmt) 2010; 28:377-81. [PMID: 19857121 DOI: 10.1089/hyb.2009.0036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We developed and characterized monoclonal antibodies directed against the amino-terminal and carboxy-terminal regions of human and mouse sclerostin (scl). Amino-terminal and carboxy-terminal scl peptides with limited homology to scl domain-containing protein-1 were synthesized using f-moc chemistry. The peptides were conjugated to keyhole limpet hemocyanin and the conjugates were used for immunization of mice. Monoclonal antibodies were obtained and characterized using bacterially expressed and insect cell-expressed recombinant scl. The amino-terminal (IgG 2aK) and carboxy-terminal (IgG 2bK) antibodies bound bioactive sclerostin that was expressed in an insect-cell expression system with dissociation constants in the nanomolar range. The antibodies are potentially useful agents that can be used for modulating sclerostin bioactivity.
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Affiliation(s)
- Theodore A Craig
- Nephrology Research, Department of Medicine, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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38
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Ran C, Xu X, Raymond SB, Ferrara BJ, Neal K, Bacskai BJ, Medarova Z, Moore A. Design, synthesis, and testing of difluoroboron-derivatized curcumins as near-infrared probes for in vivo detection of amyloid-beta deposits. J Am Chem Soc 2010; 131:15257-61. [PMID: 19807070 DOI: 10.1021/ja9047043] [Citation(s) in RCA: 324] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amyloid-beta (Abeta) deposits have been identified as key players in the progression of Alzheimer's disease (AD). Recent evidence indicates that the deposits probably precede and induce the neuronal atrophy. Therefore, methods that enable monitoring the pathology before clinical symptoms are observed would be beneficial for early AD detection. Here, we report the design, synthesis, and testing of a curcumin-derivatized near-infrared (NIR) probe, CRANAD-2. Upon interacting with Abeta aggregates, CRANAD-2 undergoes a range of changes, which include a 70-fold fluorescence intensity increase, a 90 nm blue shift (from 805 to 715 nm), and a large increase in quantum yield. Moreover, this probe also shows a high affinity for Abeta aggregates (K(d) = 38.0 nM), a reasonable log P value (log P = 3), considerable stability in serum, and a weak interaction with albumin. After intravenous injection of this probe, 19-month-old Tg2576 mice exhibited significantly higher relative signal than that of the control mice over the same period of time. In summary, CRANAD-2 meets all the requirements for a NIR contrast agent for the detection of Abeta plaques both in vitro and in vivo. Our data point toward the feasibility of monitoring the progress of the disease by NIR imaging with CRANAD-2. In addition, we believe that our probe could be potentially used as a tool for drug screening.
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Affiliation(s)
- Chongzhao Ran
- Molecular Imaging Laboratory, MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, Room 2301, Building 149, Charlestown, Massachusetts 02129, USA
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39
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Poduslo JF, Gilles EJ, Ramakrishnan M, Howell KG, Wengenack TM, Curran GL, Kandimalla KK. HH domain of Alzheimer's disease Abeta provides structural basis for neuronal binding in PC12 and mouse cortical/hippocampal neurons. PLoS One 2010; 5:e8813. [PMID: 20098681 PMCID: PMC2809098 DOI: 10.1371/journal.pone.0008813] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 12/22/2009] [Indexed: 11/18/2022] Open
Abstract
A key question in understanding AD is whether extracellular Aβ deposition of parenchymal amyloid plaques or intraneuronal Aβ accumulation initiates the AD process. Amyloid precursor protein (APP) is endocytosed from the cell surface into endosomes where it is cleaved to produce soluble Aβ which is then released into the brain interstitial fluid. Intraneuronal Aβ accumulation is hypothesized to predominate from the neuronal uptake of this soluble extracellular Aβ rather than from ER/Golgi processing of APP. We demonstrate that substitution of the two adjacent histidine residues of Aβ40 results in a significant decrease in its binding with PC12 cells and mouse cortical/hippocampal neurons. These substitutions also result in a dramatic enhancement of both thioflavin-T positive fibril formation and binding to preformed Aβ fibrils while maintaining its plaque-binding ability in AD transgenic mice. Hence, alteration of the histidine domain of Aβ prevented neuronal binding and drove Aβ to enhanced fibril formation and subsequent amyloid plaque deposition - a potential mechanism for removing toxic species of Aβ. Substitution or even masking of these Aβ histidine residues might provide a new therapeutic direction for minimizing neuronal uptake and subsequent neuronal degeneration and maximizing targeting to amyloid plaques.
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Affiliation(s)
- Joseph F Poduslo
- Molecular Neurobiology Laboratory, Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
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40
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Ono M, Hayashi S, Kimura H, Kawashima H, Nakayama M, Saji H. Push–pull benzothiazole derivatives as probes for detecting β-amyloid plaques in Alzheimer’s brains. Bioorg Med Chem 2009; 17:7002-7. [DOI: 10.1016/j.bmc.2009.08.032] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Revised: 08/04/2009] [Accepted: 08/04/2009] [Indexed: 10/20/2022]
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41
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Villemagne VL, Fodero-Tavoletti MT, Pike KE, Cappai R, Masters CL, Rowe CC. The ART of loss: Abeta imaging in the evaluation of Alzheimer's disease and other dementias. Mol Neurobiol 2008; 38:1-15. [PMID: 18690556 DOI: 10.1007/s12035-008-8019-y] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 03/28/2008] [Indexed: 01/15/2023]
Abstract
Molecular neuroimaging based on annihilation radiation tomographic (ART) techniques such as positron emission tomography (PET), in conjunction with related biomarkers in plasma and cerebrospinal fluid (CSF), are proving valuable in the early and differential diagnosis of Alzheimer's disease (AD). With the advent of new therapeutic strategies aimed at reducing beta-amyloid (Abeta) burden in the brain to potentially prevent or delay functional and irreversible cognitive loss, there is increased interest in developing agents that allow assessment of Abeta burden in vivo. Abeta burden as assessed by molecular imaging matches histopathological reports of Abeta plaque distribution in aging and dementia and appears more accurate than FDG for the diagnosis of AD. Abeta imaging is also a very powerful tool in the differential diagnosis of AD from fronto-temporal dementia (FTD). Although Abeta burden as assessed by PET does not correlate with measures of cognitive decline in AD, it does correlate with memory impairment and rate of memory decline in mild cognitive impairment (MCI) and healthy older subjects. Approximately 30% of asymptomatic controls present cortical (11)C-PiB retention. These observations suggest that Abeta deposition is not part of normal ageing, supporting the hypothesis that Abeta deposition occurs well before the onset of symptoms and is likely to represent preclinical AD. Further longitudinal observations are required to confirm this hypothesis and to better elucidate the role of Abeta deposition in the course of Alzheimer's disease.
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Affiliation(s)
- Victor L Villemagne
- Department of Nuclear Medicine, Centre for PET, Austin Health, 145 Studley Road, Heidelberg, Victoria 3084, Australia.
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42
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Abstract
Dementia represents a heterogeneous term that has evolved to describe the behavioral syndromes associated with a variety of clinical and neuropathological changes during continuing degenerative disease of the brain. As such, there lacks a clear consensus regarding the neuropsychological and other constituent characteristics associated with various cerebrovascular changes in this disease process. But increasing this knowledge has given more insights into memory deterioration in patients suffering from Alzheimer's disease and other subtypes of dementia. The author reviews current knowledge of the physiological coupling between cerebral blood flow and metabolism in the light of state-of-the-art-imaging methods and its changes in dementia with special reference to Alzheimer's disease. Different imaging techniques are discussed with respect to their visualizing effect of biochemical, cellular, and/or structural changes in dementia. The pathophysiology of dementia in advanced age is becoming increasingly understood by revealing the underlying basis of neuropsychological changes with current imaging techniques, genetic and pathological features, which suggests that alterations of (neuro) vascular regulatory mechanisms may lead to brain dysfunction and disease. The current view is that cerebrovascular deregulation is seen as a contributor to cerebrovascular pathologies, such as stroke, but also to neurodegenerative conditions, such as Alzheimer's disease. The better understanding of these (patho) physiological mechanisms may open an approach to new interventional strategies in dementia to enhance neurovascular repair and to protect neurovascular coupling.
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43
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MR microimaging of amyloid plaques in Alzheimer's disease transgenic mice. Eur J Nucl Med Mol Imaging 2008; 35 Suppl 1:S82-8. [PMID: 18239918 DOI: 10.1007/s00259-007-0706-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Alzheimer's disease (AD) is the most prevalent neurological condition affecting industrialized nations and will rapidly become a healthcare crisis as the population ages. Currently, the post-mortem histological observation of amyloid plaques and neurofibrillary tangles is the only definitive diagnosis available for AD. A pre-mortem biological or physiological marker specific for AD used in conjunction with current neurological and memory testing could add a great deal of confidence to the diagnosis of AD and potentially allow therapeutic intervention much earlier in the disease process. DISCUSSION AND CONCLUSION Our group has developed MRI techniques to detect individual amyloid plaques in AD transgenic mouse brain in vivo. We are also developing contrast-enhancing agents to increase the specificity of detection of amyloid plaques. Such in vivo imaging of amyloid plaques will also allow the evaluation of anti-amyloid therapies being developed by the pharmaceutical industry in pre-clinical trials of AD transgenic mice. This short review briefly discusses our progress in these areas.
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44
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Selective contrast enhancement of individual Alzheimer's disease amyloid plaques using a polyamine and Gd-DOTA conjugated antibody fragment against fibrillar Abeta42 for magnetic resonance molecular imaging. Pharm Res 2008; 25:1861-72. [PMID: 18443900 DOI: 10.1007/s11095-008-9600-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2008] [Accepted: 04/10/2008] [Indexed: 10/22/2022]
Abstract
PURPOSE The lack of an in vivo diagnostic test for AD has prompted the targeting of amyloid plaques with diagnostic imaging probes. We describe the development of a contrast agent (CA) for magnetic resonance microimaging that utilizes the F(ab')2 fragment of a monoclonal antibody raised against fibrillar human Abeta42 METHODS This fragment is polyamine modified to enhance its BBB permeability and its ability to bind to amyloid plaques. It is also conjugated with a chelator and gadolinium for subsequent imaging of individual amyloid plaques RESULTS Pharmacokinetic studies demonstrated this 125I-CA has higher BBB permeability and lower accumulation in the liver and kidney than F(ab')2 in WT mice. The CA retains its ability to bind Abeta40/42 monomers/fibrils and also binds to amyloid plaques in sections of AD mouse brain. Intravenous injection of 125I-CA into the AD mouse demonstrates targeting of amyloid plaques throughout the cortex/hippocampus as detected by emulsion autoradiography. Incubation of AD mouse brain slices in vitro with this CA resulted in selective enhancement on T1-weighted spin-echo images, which co-register with individual plaques observed on spatially matched T2-weighted spin-echo image CONCLUSIONS Development of such a molecular probe is expected to open new avenues for the diagnosis of AD.
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45
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Abstract
Remyelination of axons that have been demyelinated due to multiple sclerosis (MS) may be a critical step in restoring the damaged axons and reversing the disease process. While it is possible to establish the presence of remyelination with microscopy of tissue samples, it is important to have noninvasive or minimally invasive methods to measure remyelination in living animals and humans. Such tools are critical to establishing the efficacy of agents purported to promote or enhance remyelination. This chapter reviews the technology of imaging of the brain, its application to MS, and the current state of imaging techniques for measuring remyelination and the health of the associated neurons in the setting of MS.
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Affiliation(s)
- B J Erickson
- Department of Radiology, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA.
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46
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Yan GP, Robinson L, Hogg P. Magnetic resonance imaging contrast agents: Overview and perspectives. Radiography (Lond) 2007. [DOI: 10.1016/j.radi.2006.07.005] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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47
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Kamaly N, Kalber T, Ahmad A, Oliver MH, So PW, Herlihy AH, Bell JD, Jorgensen MR, Miller AD. Bimodal paramagnetic and fluorescent liposomes for cellular and tumor magnetic resonance imaging. Bioconjug Chem 2007; 19:118-29. [PMID: 17985841 DOI: 10.1021/bc7001715] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A novel bimodal fluorescent and paramagnetic liposome is described for cellular labeling. In this study, we show the synthesis of a novel gadolinium lipid, Gd.DOTA.DSA, designed for liposomal cell labeling and tumor imaging. Liposome formulations consisting of this lipid were optimized in order to allow for maximum cellular entry, and the optimized formulation was used to label HeLa cells in vitro. The efficiency of this novel bimodal Gd-liposome formulation for cell labeling was demonstrated using both fluorescence microscopy and magnetic resonance imaging (MRI). The uptake of Gd-liposomes into cells induced a marked reduction in their MRI T 1 relaxation times. Fluorescence microscopy provided concomitant proof of uptake and revealed liposome internalization into the cell cytosol. The optimized formulation was also found to exhibit minimal cytotoxicity and was shown to have capacity for plasmid DNA (pDNA) transfection. A further second novel neutral bimodal Gd-liposome is described for the labeling of xenograft tumors in vivo utilizing the enhanced permeation and retention effect (EPR). Balb/c nude mice were inoculated with IGROV-1 cells, and the resulting tumor was imaged by MRI using these in vivo Gd-liposomes formulated with low charge and a poly(ethylene glycol) (PEG) calyx for long systemic circulation. These Gd-liposomes which were less than 100 nm in size were shown to accumulate in tumor tissue by MRI, and this was also verified by fluorescence microscopy of histology samples. Our in vivo tumor imaging results demonstrate the effectiveness of MRI to observe passive targeting of long-term circulating liposomes to tumors in real time, and allow for MRI directed therapy, wherein the delivery of therapeutic genes and drugs to tumor sites can be monitored while therapeutic effects on tumor mass and/or size may be simultaneously observed, quantitated, and correlated.
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Affiliation(s)
- Nazila Kamaly
- Imperial College Genetic Therapies Centre, Department of Chemistry, Flowers Building, Armstrong Road, Imperial College London, London, SW7 2AZ, United Kingdom
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El Tayara NET, Volk A, Dhenain M, Delatour B. Transverse relaxation time reflects brain amyloidosis in young APP/PS1 transgenic mice. Magn Reson Med 2007; 58:179-184. [PMID: 17659609 DOI: 10.1002/mrm.21266] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Amyloid deposits are one of the hallmarks of Alzheimer's disease (AD), one of the most devastating neurodegenerative disorders. In transgenic mice modeling Alzheimer's pathology, the MR transverse relaxation time (T(2)) has been described to be modulated by amyloidosis. This modification has been attributed to the age-related iron deposition that occurs within the amyloid plaques of old animals. In the present study, young APP/PS1 transgenic mice without histochemically detectable iron in the brain were specifically studied. In vivo measurements of T(2) in the hippocampus, at the level of the subiculum, were shown to reflect the density of amyloid plaques. This suggests that T(2) variations can be induced solely by aggregated amyloid deposits in the absence of associated histologically-detectable iron. Thus T(2) from regions with high amyloid load, such as the subiculum, is particularly well suited for following plaque deposition in young animals, i.e., at the earliest stages of the pathological process.
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Affiliation(s)
- Nadine El Tannir El Tayara
- INSERM, U759, Centre Universitaire, Orsay, France
- Institut Curie Research Center, Centre Universitaire, Orsay, France
| | - Andreas Volk
- INSERM, U759, Centre Universitaire, Orsay, France
- Institut Curie Research Center, Centre Universitaire, Orsay, France
| | - Marc Dhenain
- INSERM, U759, Centre Universitaire, Orsay, France
- Institut Curie Research Center, Centre Universitaire, Orsay, France
- CEA, SHFJ, URA CEA CNRS 2210, Orsay, France
| | - Benoît Delatour
- Laboratoire NAMC, CNRS, UMR 8620, Bât 446, Université Paris Sud, Orsay, France
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49
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Kandimalla KK, Wengenack TM, Curran GL, Gilles EJ, Poduslo JF. Pharmacokinetics and Amyloid Plaque Targeting Ability of a Novel Peptide-Based Magnetic Resonance Contrast Agent in Wild-Type and Alzheimer's Disease Transgenic Mice. J Pharmacol Exp Ther 2007; 322:541-9. [PMID: 17505020 DOI: 10.1124/jpet.107.119883] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A novel magnetic resonance (MR) imaging contrast agent based on a derivative of human amyloid beta (Abeta) peptide, Gd[N-4ab/Q-4ab]Abeta 30, was previously shown to cross the blood-brain barrier (BBB) and bind to amyloid plaques in Alzheimer's disease (AD) transgenic mouse (APP/PS1) brain. We now report extensive plasma and brain pharmacokinetics of this contrast agent in wild-type (WT) and in APP/PS1 mice along with a quantitative summary of various physiological factors that govern its efficacy. Upon i.v. bolus administration, (125)I-Gd[N-4ab/Q-4ab]Abeta 30 was rapidly eliminated from the plasma following a three-exponential disposition, which is saturable at higher concentrations. Nevertheless, the contrast agent exhibited rapid and nonsaturable absorption at the BBB. The brain pharmacokinetic profile of (125)I-Gd[N-4ab/Q-4ab]Abeta 30 showed a rapid absorption phase followed by a slower elimination phase. No significant differences were observed in the plasma or brain kinetics of WT and APP/PS1 animals. Emulsion autoradiography studies conducted on WT and APP/PS1 mouse brain after an i.v. bolus administration of (125)I-Gd[N-4ab/Q-4ab]Abeta 30 in vivo confirmed the brain pharmacokinetic data and also demonstrated the preferential localization of the contrast agent on the plaques for an extended period of time. These attributes of the contrast agent are extremely useful in providing an excellent signal/noise ratio during longer MR scans, which may be essential for obtaining a high resolution image. In conclusion, this study documents the successful plaque targeting of Gd[N-4ab/Q-4ab]Abeta 30 and provides crucial pharmacokinetic information to determine the dose, mode of administration, and scan times for future in vivo MR imaging of amyloid plaques in AD transgenic mice.
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Canet E. Medicen Paris Région, pôle de compétitivité mondial et recherche en neuroscience. Med Sci (Paris) 2007; 23:435-9. [PMID: 17433236 DOI: 10.1051/medsci/2007234435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The French public-private partnerships known as "competitive clusters" [pôles de compétitivité (PdC)] are intended to be novel and ambitious engines of regional growth, employment and biomedical innovation. Partly funded by government and local councils, they aim to capitalize on regional expertise by bringing together basic scientists, clinicians, innovative entrepreneurs and local decision-makers around specific themes that have become too costly and complex for any of these actors to tackle alone. Clusters provide the critical mass required both to underpin innovation potential and to authenticate regional claims to international competitiveness. Medicen is a biomedicine and therapeutics cluster comprising 120 partners from four broad "colleges" in the greater Paris region: major industry, small and medium-sized businesses, teaching hospitals/State research bodies, and local councils. Chief among its cooperative R&D projects is the neuroscience subcluster, in which "TransAl" the neurodegenerative disease project, counts Sanofi-Aventis, Servier and the French Atomic Energy Commission [Commissariat à l'Energie Atomique (CEA)] as key partners. One main aim is to develop an experimental model in rhesus monkeys in which a putative cause of Alzheimer's disease, intracerebral accumulation of b-amyloid peptide, is generated by impairing the peptide's clearance. The other aim, in which the nuclear medicine expertise of the CEA will be crucial, is to identify, characterize and validate markers for magnetic resonance and positron emission tomography imaging, and to source biomarkers from cerebrospinal fluid proteomics. A human biological resource centre (DNA and tissue banks) project dedicated to neurological and psychiatric disease should be up and running in 2007. Only through fundamental restructuring of resources on such a large cooperative scale are solutions likely to be found to the major problems of modern medicine, bringing healthcare and regional socioeconomic benefits in its wake.
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Affiliation(s)
- Emmanuel Canet
- Institut de recherches internationales Servier, 6, place des Pléiades, 92415 Courbevoie, France
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