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Shoemaker RL, Larsen RJ, Larsen PA. Single-domain antibodies and aptamers drive new opportunities for neurodegenerative disease research. Front Immunol 2024; 15:1426656. [PMID: 39238639 PMCID: PMC11374656 DOI: 10.3389/fimmu.2024.1426656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 07/22/2024] [Indexed: 09/07/2024] Open
Abstract
Neurodegenerative diseases (NDs) in mammals, such as Alzheimer's disease (AD), Parkinson's disease (PD), and transmissible spongiform encephalopathies (TSEs), are characterized by the accumulation of misfolded proteins in the central nervous system (CNS). Despite the presence of these pathogenic proteins, the immune response in affected individuals remains notably muted. Traditional immunological strategies, particularly those reliant on monoclonal antibodies (mAbs), face challenges related to tissue penetration, blood-brain barrier (BBB) crossing, and maintaining protein stability. This has led to a burgeoning interest in alternative immunotherapeutic avenues. Notably, single-domain antibodies (or nanobodies) and aptamers have emerged as promising candidates, as their reduced size facilitates high affinity antigen binding and they exhibit superior biophysical stability compared to mAbs. Aptamers, synthetic molecules generated from DNA or RNA ligands, present both rapid production times and cost-effective solutions. Both nanobodies and aptamers exhibit inherent qualities suitable for ND research and therapeutic development. Cross-seeding events must be considered in both traditional and small-molecule-based immunodiagnostic and therapeutic approaches, as well as subsequent neurotoxic impacts and complications beyond protein aggregates. This review delineates the challenges traditional immunological methods pose in ND research and underscores the potential of nanobodies and aptamers in advancing next-generation ND diagnostics and therapeutics.
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Affiliation(s)
- Rachel L Shoemaker
- Minnesota Center for Prion Research and Outreach (MNPRO), University of Minnesota, St. Paul, MN, United States
- Department of Biomedical and Veterinary Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN, United States
| | - Roxanne J Larsen
- Department of Biomedical and Veterinary Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN, United States
- Priogen Corp., St. Paul, MN, United States
| | - Peter A Larsen
- Minnesota Center for Prion Research and Outreach (MNPRO), University of Minnesota, St. Paul, MN, United States
- Department of Biomedical and Veterinary Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN, United States
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2
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Litke JL, Jaffrey SR. Designing and Expressing Circular RNA Aptamers to Regulate Mammalian Cell Biology. Methods Mol Biol 2023; 2570:223-234. [PMID: 36156786 PMCID: PMC9797029 DOI: 10.1007/978-1-0716-2695-5_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
RNA aptamers can be genetically encoded in cells to probe and manipulate cellular function. The usefulness of aptamers in mammalian cells is limited by low accumulation and degradation by ribonucleases. Expression of circular RNA aptamers using the Tornado expression system achieves high stability and an abundance of intracellular RNA aptamers. With this method, RNA aptamers with otherwise minimal activity become potent inhibitors. Here, we describe protocols to characterize circular RNA aptamers expressed using Tornado. Included are methods to assess stability, abundance, subcellular localization, and target binding by circular RNA aptamers.
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Affiliation(s)
- Jacob L Litke
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA
| | - Samie R Jaffrey
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA.
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3
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Khan I, Preeti K, Fernandes V, Khatri DK, Singh SB. Role of MicroRNAs, Aptamers in Neuroinflammation and Neurodegenerative Disorders. Cell Mol Neurobiol 2022; 42:2075-2095. [PMID: 33934227 DOI: 10.1007/s10571-021-01093-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 04/19/2021] [Indexed: 02/07/2023]
Abstract
Exploring the microRNAs and aptamers for their therapeutic role as biological drugs has expanded the horizon of its applicability against various human diseases, explicitly targeting the genetic materials. RNA-based therapeutics are widely being explored for the treatment and diagnosis of multiple diseases, including neurodegenerative disorders (NDD). Latter includes microRNA, aptamers, ribozymes, and small interfering RNAs (siRNAs), which control the gene expression mainly at the transcriptional strata. One RNA transcript translates into different protein types; hence, therapies targeted at the transcriptional sphere may have prominent and more extensive effects than alternative therapeutics. Unlike conventional gene therapy, RNAs, upon delivery, can either altogether abolish or alter the synthesis of the protein of interest, therefore, regulating their activities in a controlled and diverse manner. NDDs like Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, Prion disease, and others are characterized by deposition of misfolded protein such as amyloid-ß, tau, α-synuclein, huntingtin and prion proteins. Neuroinflammation, one of the perquisites for neurodegeneration, is induced during neurodegenerative pathogenesis. In this review, we discuss microRNAs and aptamers' role as two different RNA-based approaches for their unique ability to regulate protein production at the transcription level, hence offering many advantages over other biologicals. The microRNA acts either by alleviating the malfunctioning RNA expression or by working as a replacement to lost microRNA. On the contrary, aptamer act as a chemical antibody and forms an aptamer-target complex.
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Affiliation(s)
- Islauddin Khan
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Balanagar, Hyderabad, Telangana, 500037, India
| | - Kumari Preeti
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Balanagar, Hyderabad, Telangana, 500037, India
| | - Valencia Fernandes
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Balanagar, Hyderabad, Telangana, 500037, India
| | - Dharmendra Kumar Khatri
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Balanagar, Hyderabad, Telangana, 500037, India.
| | - Shashi Bala Singh
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Balanagar, Hyderabad, Telangana, 500037, India.
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4
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Mollasalehi N, Francois-Moutal L, Porciani D, Burke DH, Khanna M. Aptamers Targeting Hallmark Proteins of Neurodegeneration. Nucleic Acid Ther 2022; 32:235-250. [PMID: 35452303 DOI: 10.1089/nat.2021.0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Neurodegeneration is a progressive deterioration of neural structures leading to cognitive or motor impairment of the affected patient. There is still no effective therapy for any of the most common neurodegenerative diseases (NDs) such as Alzheimer's or Parkinson's disease. Although NDs exhibit distinct clinical characteristics, many are characterized by the accumulation of misfolded proteins or peptide fragments in the brain and/or spinal cord. The presence of similar inclusion bodies in patients with diverse NDs provides a rationale for developing therapies directed at overlapping disease mechanisms. A novel targeting strategy involves the use of aptamers for therapeutic development. Aptamers are short nucleic acid ligands able to recognize molecular targets with high specificity and high affinity. Despite the fact that several academic groups have shown that aptamers have the potential to be used in therapeutic and diagnostic applications, their clinical translation is still limited. In this study, we describe aptamers that have been developed against proteins relevant to NDs, including prion protein and amyloid beta (Aβ), cell surface receptors and other cytoplasmic proteins. This review also describes advances in the application of these aptamers in imaging, protein detection, and protein quantification, and it provides insights about their accelerated clinical use for disease diagnosis and therapy.
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Affiliation(s)
- Niloufar Mollasalehi
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, USA.,Center for Innovation in Brain Science, Tucson, Arizona, USA
| | - Liberty Francois-Moutal
- Center for Innovation in Brain Science, Tucson, Arizona, USA.,Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona, USA
| | - David Porciani
- Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri-Columbia, Columbia, Missouri, USA.,MU Bond Life Sciences Center, University of Missouri-Columbia, Columbia, Missouri, USA
| | - Donald H Burke
- Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri-Columbia, Columbia, Missouri, USA.,MU Bond Life Sciences Center, University of Missouri-Columbia, Columbia, Missouri, USA
| | - May Khanna
- Center for Innovation in Brain Science, Tucson, Arizona, USA.,Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona, USA
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Mahaman YAR, Embaye KS, Huang F, Li L, Zhu F, Wang JZ, Liu R, Feng J, Wang X. Biomarkers used in Alzheimer's disease diagnosis, treatment, and prevention. Ageing Res Rev 2022; 74:101544. [PMID: 34933129 DOI: 10.1016/j.arr.2021.101544] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/09/2021] [Accepted: 12/15/2021] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD), being the number one in terms of dementia burden, is an insidious age-related neurodegenerative disease and is presently considered a global public health threat. Its main histological hallmarks are the Aβ senile plaques and the P-tau neurofibrillary tangles, while clinically it is marked by a progressive cognitive decline that reflects the underlying synaptic loss and neurodegeneration. Many of the drug therapies targeting the two pathological hallmarks namely Aβ and P-tau have been proven futile. This is probably attributed to the initiation of therapy at a stage where cognitive alterations are already obvious. In other words, the underlying neuropathological changes are at a stage where these drugs lack any therapeutic value in reversing the damage. Therefore, there is an urgent need to start treatment in the very early stage where these changes can be reversed, and hence, early diagnosis is of primordial importance. To this aim, the use of robust and informative biomarkers that could provide accurate diagnosis preferably at an earlier phase of the disease is of the essence. To date, several biomarkers have been established that, to a different extent, allow researchers and clinicians to evaluate, diagnose, and more specially exclude other related pathologies. In this study, we extensively reviewed data on the currently explored biomarkers in terms of AD pathology-specific and non-specific biomarkers and highlighted the recent developments in the diagnostic and theragnostic domains. In the end, we have presented a separate elaboration on aspects of future perspectives and concluding remarks.
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Abstract
RNA-based therapeutics have entered the mainstream with seemingly limitless possibilities to treat all categories of neurological disease. Here, common RNA-based drug modalities such as antisense oligonucleotides, small interfering RNAs, RNA aptamers, RNA-based vaccines and mRNA drugs are reviewed highlighting their current and potential applications. Rapid progress has been made across rare genetic diseases and neurodegenerative disorders, but safe and effective delivery to the brain remains a significant challenge for many applications. The advent of individualized RNA-based therapies for ultra-rare diseases is discussed against the backdrop of the emergence of this field into more common conditions such as Alzheimer's disease and ischaemic stroke. There remains significant untapped potential in the use of RNA-based therapeutics for behavioural disorders and tumours of the central nervous system; coupled with the accelerated development expected over the next decade, the true potential of RNA-based therapeutics to transform the therapeutic landscape in neurology remains to be uncovered.
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Affiliation(s)
- Karen Anthony
- Centre for Physical Activity and Life Sciences, University of Northampton, Northampton, UK
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7
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Ozturk M, Nilsen-Hamilton M, Ilgu M. Aptamer Applications in Neuroscience. Pharmaceuticals (Basel) 2021; 14:1260. [PMID: 34959661 PMCID: PMC8709198 DOI: 10.3390/ph14121260] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 02/07/2023] Open
Abstract
Being the predominant cause of disability, neurological diseases have received much attention from the global health community. Over a billion people suffer from one of the following neurological disorders: dementia, epilepsy, stroke, migraine, meningitis, Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis, Huntington's disease, prion disease, or brain tumors. The diagnosis and treatment options are limited for many of these diseases. Aptamers, being small and non-immunogenic nucleic acid molecules that are easy to chemically modify, offer potential diagnostic and theragnostic applications to meet these needs. This review covers pioneering studies in applying aptamers, which shows promise for future diagnostics and treatments of neurological disorders that pose increasingly dire worldwide health challenges.
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Affiliation(s)
- Meric Ozturk
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA; (M.O.); (M.N.-H.)
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
| | - Marit Nilsen-Hamilton
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA; (M.O.); (M.N.-H.)
- Ames Laboratory, US DOE (United States Department of Energy), Ames, IA 50011, USA
- Aptalogic Inc., Ames, IA 50014, USA
| | - Muslum Ilgu
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA; (M.O.); (M.N.-H.)
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
- Ames Laboratory, US DOE (United States Department of Energy), Ames, IA 50011, USA
- Aptalogic Inc., Ames, IA 50014, USA
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Mikuła E. Recent Advancements in Electrochemical Biosensors for Alzheimer's Disease Biomarkers Detection. Curr Med Chem 2021; 28:4049-4073. [PMID: 33176635 PMCID: PMC8287894 DOI: 10.2174/0929867327666201111141341] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/28/2020] [Accepted: 10/07/2020] [Indexed: 02/06/2023]
Abstract
Background It is estimated that the average time between the diagnosis of Alzheimer’s disease (AD) and the patient’s death is 5-9 years. Therefore, both the initial phase of the disease and the preclinical state can be included in the critical period in disease diagnosis. Accordingly, huge progress has recently been observed in biomarker research to identify risk factors for dementia in older people with normal cognitive functions and mild cognitive impairments. Methods Electrochemical biosensors are excellent analytical tools that are used in the detection of AD biomarkers as they are easy to use, portable, and can do analysis in real time. Results This review presents the analytical techniques currently used to determine AD biomarkers in terms of their advantages and disadvantages; the most important clinical biomarkers of AD and their role in the disease. All recently used biorecognition molecules in electrochemical biosensor development, i.e., receptor protein, antibodies, aptamers and nucleic acids, are summarized for the first time. Novel electrochemical biosensors for AD biomarker detection, as ideal analytical platforms for point-of-care diagnostics, are also reviewed. Conclusion The article focuses on various strategies of biosensor chemical surface modifications to immobilize biorecognition molecules, enabling specific, quantitative AD biomarker detection in synthetic and clinical samples. In addition, this is the first review that presents innovative single-platform systems for simultaneous detection of multiple biomarkers and other important AD-associated biological species based on electrochemical techniques. The importance of these platforms in disease diagnosis is discussed.
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Affiliation(s)
- Edyta Mikuła
- Department of Biosensors, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima 10, 10-748 Olsztyn, Poland
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9
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Liu L, Gao H, Guo C, Liu T, Li N, Qian Q. Therapeutic Mechanism of Nucleic Acid Drugs. ChemistrySelect 2021. [DOI: 10.1002/slct.202002901] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Lianxiao Liu
- Nucleic Acid Drug Division Shanghai Cell Therapy Group Co., Ltd. 75 A Qianyang Rd, Jiading District Shanghai 201805 China
| | - Haixia Gao
- Nucleic Acid Drug Division Shanghai Cell Therapy Group Co., Ltd. 75 A Qianyang Rd, Jiading District Shanghai 201805 China
| | - Chuanxin Guo
- Nucleic Acid Drug Division Shanghai Cell Therapy Group Co., Ltd. 75 A Qianyang Rd, Jiading District Shanghai 201805 China
| | - Tao Liu
- Nucleic Acid Drug Division Shanghai Cell Therapy Group Co., Ltd. 75 A Qianyang Rd, Jiading District Shanghai 201805 China
| | - Ning Li
- Nucleic Acid Drug Division Shanghai Cell Therapy Group Co., Ltd. 75 A Qianyang Rd, Jiading District Shanghai 201805 China
| | - Qijun Qian
- Nucleic Acid Drug Division Shanghai Cell Therapy Group Co., Ltd. 75 A Qianyang Rd, Jiading District Shanghai 201805 China
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Allemailem KS, Almatroudi A, Alsahli MA, Basfar GT, Alrumaihi F, Rahmani AH, Khan AA. Recent advances in understanding oligonucleotide aptamers and their applications as therapeutic agents. 3 Biotech 2020; 10:551. [PMID: 33269185 PMCID: PMC7686427 DOI: 10.1007/s13205-020-02546-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 11/06/2020] [Indexed: 12/12/2022] Open
Abstract
The innovative discovery of aptamers was based on target-specific treatment in clinical diagnostics and therapeutics. Aptamers are synthetic, single-stranded oligonucleotides, simply described as chemical antibodies, which can bind to diverse targets with high specificity and affinity. Aptamers are synthesized by the SELEX technique, and possess distinctive properties as small size (10-50 kDa), higher stability, easy manufacture and less immunogenicity. These oligonucleotides are easily degraded by nucleases, so require some important modifications like capping and incorporation of modified nucleotides. RNA aptamers can be modified chemically on 2' positions using -NH3, -F, -deoxy, or -OMe groups to enhance their nuclease resistance. Aptamers have been employed for multiple purposes, as direct drugs or aptamer-drug conjugates targeted against different diseased cells. Different aptamer-conjugated nanovehicles (e.g., micelles, liposomes, silica nano-shells) have been designed to transport diverse anticancer-drugs like doxorubicin and cisplatin in bulk to minimize systemic cytotoxicity. Some drug-loaded nanovehicles (up to 97% loading capacity) and conjugated with specific aptamer resulted in more than 60% tumor inhibition as compared to unconjugated drug-loaded nanovehicles which showed only 31% cancer inhibition. In addition, aptamers have been widely used in basic research, food safety, environmental monitoring, clinical diagnostics and therapeutics. Different FDA-approved RNA and DNA aptamers are now available in the market, used for the treatment of diverse diseases, especially cancer. These aptamers include Macugen, Pegaptanib, etc. Despite a good progress in aptamer use, the present-day chemotherapeutics and drug targeting systems still face great challenges. Here in this review article, we are discussing nucleic acid aptamers, preparation, role in the transportation of different nanoparticle vehicles and their applications as therapeutic agents.
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Affiliation(s)
- Khaled S. Allemailem
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
- Department of Basic Health Sciences, College of Applied Medical Sciences, Qassim University, P.O. Box 6699, Buraydah, 51452 Saudi Arabia
| | - Ahmad Almatroudi
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
| | - Mohammed A. Alsahli
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
| | - Ghaiyda Talal Basfar
- Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Faris Alrumaihi
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
| | - Arshad Husain Rahmani
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
| | - Amjad Ali Khan
- Department of Basic Health Sciences, College of Applied Medical Sciences, Qassim University, P.O. Box 6699, Buraydah, 51452 Saudi Arabia
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Xiang J, Zhang W, Cai XF, Cai M, Yu ZH, Yang F, Zhu W, Li XT, Wu T, Zhang JS, Cai DF. DNA Aptamers Targeting BACE1 Reduce Amyloid Levels and Rescue Neuronal Deficiency in Cultured Cells. MOLECULAR THERAPY. NUCLEIC ACIDS 2019; 16:302-312. [PMID: 30959405 PMCID: PMC6453838 DOI: 10.1016/j.omtn.2019.02.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 02/03/2019] [Accepted: 02/04/2019] [Indexed: 01/02/2023]
Abstract
β-amyloid (Aβ) plays an essential role in the pathogenesis of Alzheimer's disease (AD). Beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) is indispensable for Aβ production, and knockout of BACE1 has no overt phenotypes in mouse. Thus, fine modulation of BACE1 may be a safe and effective treatment for AD patients. However, the large active site of BACE1 makes it challenging to target BACE1 with classical small-molecule inhibitors. DNA aptamer can have high affinity and specificity against diverse targets, and it provides an alternative strategy to target BACE1. In this study, we used a novel cell-systematic evolution of ligands by exponential enrichment (SELEX) strategy to select specific DNA aptamers optimized to target BACE1 under physiological status. After 17 rounds of selection, we identified two DNA aptamers against BACE1: BI1 and BI2. The identified aptamers interacted with BACE1 in pull-down assay, inhibited BACE1 activity in in vitro fluorescence resonance energy transfer (FRET) assay and HEK293-APP stable cell line, reduced Aβ in the culture medium of HEK293-amyloid protein precursor (APP) stable cell line and APP-PS1 primary cultured neurons, and rescued Aβ-induced neuronal deficiency in APP-PS1 primary cultured neurons. In contrast, the identified aptamers had no effect on α- or γ-secretase. In addition, cholesteryl tetraetylene glycol (TEG) modification further improved the potency of the identified aptamers. Our study suggests that it is feasible and effective to target BACE1 with DNA aptamers, and the therapeutic potential of the identified aptamers deserves further investigation.
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Affiliation(s)
- Jun Xiang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Wen Zhang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Xiao-Fang Cai
- Department of Stomatology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Min Cai
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Zhong-Hai Yu
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Feng Yang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Wen Zhu
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Xiang-Ting Li
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Ting Wu
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China
| | - Jing-Si Zhang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China.
| | - Ding-Fang Cai
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Laboratory of Neurology, Institute of Integrative Medicine, Fudan University, Shanghai 200032, China.
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12
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Litke JL, Jaffrey SR. Highly efficient expression of circular RNA aptamers in cells using autocatalytic transcripts. Nat Biotechnol 2019; 37:667-675. [PMID: 30962542 PMCID: PMC6554452 DOI: 10.1038/s41587-019-0090-6] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 03/01/2019] [Indexed: 12/13/2022]
Abstract
RNA aptamers and RNA aptamer-based devices can be genetically encoded and expressed in cells to probe and manipulate cellular function. However, their usefulness in the mammalian cell is limited by low expression and rapid degradation. Here we describe the Tornado (Twister-optimized RNA for durable overexpression) expression system for achieving rapid RNA circularization, resulting in RNA aptamers with high stability and expression levels. Tornado-expressed transcripts contain an RNA of interest flanked by Twister ribozymes. The ribozymes rapidly undergo autocatalytic cleavage, leaving termini that are ligated by the ubiquitous endogenous RNA ligase RtcB. Using this approach, protein-binding aptamers that otherwise have minimal effects in cells become potent inhibitors of cellular signaling. Additionally, an RNA-based fluorescent metabolite biosensor for S-adenosyl methionine (SAM) that is expressed at low levels when expressed as a linear RNA achieves levels sufficient for detection of intracellular SAM dynamics when expressed as a circular RNA. The Tornado expression system thus markedly enhances the utility of RNA-based approaches in the mammalian cell.
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Affiliation(s)
- Jacob L Litke
- Tri-Institutional PhD Program in Chemical Biology, Weill Cornell Medicine, The Rockefeller University, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Pharmacology, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Samie R Jaffrey
- Tri-Institutional PhD Program in Chemical Biology, Weill Cornell Medicine, The Rockefeller University, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Department of Pharmacology, Weill Cornell Medicine, Cornell University, New York, NY, USA.
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13
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Therapeutic aptamers in discovery, preclinical and clinical stages. Adv Drug Deliv Rev 2018; 134:51-64. [PMID: 30125605 DOI: 10.1016/j.addr.2018.08.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/11/2018] [Accepted: 08/16/2018] [Indexed: 02/06/2023]
Abstract
The aptamer field witnessed steady growth during the past 28 years as evident from the exponentially increasing number of related publications. The field is "coming of age", but like other biomedical research areas facing a global push towards translational research to carry ideas from bench- to bedside, there is pressure to show impact for aptamers at the clinical end. Being easy-to-make, non-immunogenic, stable and high-affinity nano-ligands, aptamers are perfectly poised to move in this direction. They can specifically bind targets ranging from small molecules to complex multimeric structures, making them potentially useful in a limitless variety of therapeutic approaches. This review will summarize efforts made to accomplish the therapeutic promise of aptamers, with a focus on aptamers directly acting as therapeutic molecules, rather than those used in targeted delivery of other drugs. The review will showcase representative examples at various stages of development, covering different disease categories.
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14
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Gasse C, Zaarour M, Noppen S, Abramov M, Marlière P, Liekens S, De Strooper B, Herdewijn P. Modulation of BACE1 Activity by Chemically Modified Aptamers. Chembiochem 2018; 19:754-763. [PMID: 29327496 DOI: 10.1002/cbic.201700461] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/10/2018] [Indexed: 11/10/2022]
Abstract
A modified DNA aptamer that binds BACE1, a therapeutic target involved in Alzheimer's disease has been developed. This ssXNA not only tightly binds to BACE1 but also inhibits its protease activity in vitro in the same range as a previously described unmodified aptamer. We report the in vitro selection of functional oligonucleotides incorporating two nucleobase modifications: 5-chlorouracil and 7-deazaadenine. The nucleoside analogue 5-chloro-2'-deoxyuridine has already been explored as a replacement for thymidine in a chemically modified genome of a bacterium. Thus, 5-chlorouracil modification is a good candidate to support genetic transfer in vivo as well as functional activity.
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Affiliation(s)
- Cécile Gasse
- Univ Evry, CNRS-UMR8030-Laboratoire iSSB, CEA, DRF, IG, Genoscope, Université Paris-Saclay, 5 rue Henri Desbruères, Évry, 91030, France
| | - Marwa Zaarour
- Univ Evry, CNRS-UMR8030-Laboratoire iSSB, CEA, DRF, IG, Genoscope, Université Paris-Saclay, 5 rue Henri Desbruères, Évry, 91030, France
| | - Sam Noppen
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven, Herestraat 49, Postbus 1043, 3000, Leuven, Belgium
| | - Mikhail Abramov
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Philippe Marlière
- The European Syndicate of Synthetic Scientists and Industrialists (TESSI), 81 rue Réaumur, 75002, Paris, France
| | - Sandra Liekens
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven, Herestraat 49, Postbus 1043, 3000, Leuven, Belgium
| | - Bart De Strooper
- VIB, Center for Brain & Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Department of Neurosciences, Leuven Institute for Neuroscience and Disease, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.,Dementia Research Institute (UK), University College London, Gower Street, WC1E 6BT, London, UK
| | - Piet Herdewijn
- Univ Evry, CNRS-UMR8030-Laboratoire iSSB, CEA, DRF, IG, Genoscope, Université Paris-Saclay, 5 rue Henri Desbruères, Évry, 91030, France.,Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
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15
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Bouvier-Müller A, Ducongé F. Nucleic acid aptamers for neurodegenerative diseases. Biochimie 2017; 145:73-83. [PMID: 29104136 DOI: 10.1016/j.biochi.2017.10.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 10/31/2017] [Indexed: 02/07/2023]
Abstract
The increased incidence of neurodegenerative diseases represents a huge challenge for societies. These diseases are characterized by neuronal death and include several different pathologies, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, Huntington's disease and transmissible spongiform encephalopathies. Most of these pathologies are often associated with the aggregation of misfolded proteins, such as amyloid-ß, tau, α-synuclein, huntingtin and prion proteins. However, the precise mechanisms that lead to neuronal dysfunction and death in these diseases remain poorly understood. Nucleic acid aptamers represent a new class of ligands that could be useful to better understand these diseases and develop better diagnosis and therapy. In this review, several of these aptamers are presented as well as their applications for neurodegenerative diseases.
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Affiliation(s)
- Alix Bouvier-Müller
- CEA, Fundamental Research Division (DRF), Institute of Biology François Jacob (Jacob), Molecular Imaging Research Center, 18 Route du Panorama, 92265 Fontenay-aux-Roses, France; Neurodegenerative Diseases Laboratory, CNRS CEA UMR 9199, Fontenay-aux-Roses, France; Paris-Saclay University, Paris-Sud University, Fontenay-aux-Roses, France
| | - Frédéric Ducongé
- CEA, Fundamental Research Division (DRF), Institute of Biology François Jacob (Jacob), Molecular Imaging Research Center, 18 Route du Panorama, 92265 Fontenay-aux-Roses, France; Neurodegenerative Diseases Laboratory, CNRS CEA UMR 9199, Fontenay-aux-Roses, France; Paris-Saclay University, Paris-Sud University, Fontenay-aux-Roses, France.
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16
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Röthlisberger P, Gasse C, Hollenstein M. Nucleic Acid Aptamers: Emerging Applications in Medical Imaging, Nanotechnology, Neurosciences, and Drug Delivery. Int J Mol Sci 2017; 18:E2430. [PMID: 29144411 PMCID: PMC5713398 DOI: 10.3390/ijms18112430] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 11/08/2017] [Accepted: 11/09/2017] [Indexed: 12/25/2022] Open
Abstract
Recent progresses in organic chemistry and molecular biology have allowed the emergence of numerous new applications of nucleic acids that markedly deviate from their natural functions. Particularly, DNA and RNA molecules-coined aptamers-can be brought to bind to specific targets with high affinity and selectivity. While aptamers are mainly applied as biosensors, diagnostic agents, tools in proteomics and biotechnology, and as targeted therapeutics, these chemical antibodies slowly begin to be used in other fields. Herein, we review recent progress on the use of aptamers in the construction of smart DNA origami objects and MRI and PET imaging agents. We also describe advances in the use of aptamers in the field of neurosciences (with a particular emphasis on the treatment of neurodegenerative diseases) and as drug delivery systems. Lastly, the use of chemical modifications, modified nucleoside triphosphate particularly, to enhance the binding and stability of aptamers is highlighted.
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Affiliation(s)
- Pascal Röthlisberger
- Institut Pasteur, Department of Structural Biology and Chemistry, Laboratory for Bioorganic Chemistry of Nucleic Acids, CNRS UMR3523, 28, rue du Docteur Roux, 75724 Paris CEDEX 15, France.
| | - Cécile Gasse
- Institute of Systems & Synthetic Biology, Xenome Team, 5 rue Henri Desbruères Genopole Campus 1, University of Evry, F-91030 Evry, France.
| | - Marcel Hollenstein
- Institut Pasteur, Department of Structural Biology and Chemistry, Laboratory for Bioorganic Chemistry of Nucleic Acids, CNRS UMR3523, 28, rue du Docteur Roux, 75724 Paris CEDEX 15, France.
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17
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Chakravarthy M, Chen S, Dodd PR, Veedu RN. Nucleic Acid-Based Theranostics for Tackling Alzheimer's Disease. Theranostics 2017; 7:3933-3947. [PMID: 29109789 PMCID: PMC5667416 DOI: 10.7150/thno.21529] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 07/28/2017] [Indexed: 02/07/2023] Open
Abstract
Nucleic acid-based technologies have received significant interest in recent years as novel theranostic strategies for various diseases. The approval by the United States Food and Drug Administration (FDA) of Nusinersen, an antisense oligonucleotide drug, for the treatment of spinal muscular dystrophy highlights the potential of nucleic acids to treat neurological diseases, including Alzheimer's disease (AD). AD is a devastating neurodegenerative disease characterized by progressive impairment of cognitive function and behavior. It is the most common form of dementia; it affects more than 20% of people over 65 years of age and leads to death 7-15 years after diagnosis. Intervention with novel agents addressing the underlying molecular causes is critical. Here we provide a comprehensive review on recent developments in nucleic acid-based theranostic strategies to diagnose and treat AD.
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Affiliation(s)
- Madhuri Chakravarthy
- Centre for Comparative Genomics, Murdoch University, Murdoch, Perth, Australia 6150
- Perron Institute for Neurological and Translational Science, QEII Medical Centre, Nedlands, Perth, Australia 6005
| | - Suxiang Chen
- Centre for Comparative Genomics, Murdoch University, Murdoch, Perth, Australia 6150
- Perron Institute for Neurological and Translational Science, QEII Medical Centre, Nedlands, Perth, Australia 6005
| | - Peter R. Dodd
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Brisbane, Australia 4072
| | - Rakesh N. Veedu
- Centre for Comparative Genomics, Murdoch University, Murdoch, Perth, Australia 6150
- Perron Institute for Neurological and Translational Science, QEII Medical Centre, Nedlands, Perth, Australia 6005
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Brisbane, Australia 4072
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18
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Qu J, Yu S, Zheng Y, Zheng Y, Yang H, Zhang J. Aptamer and its applications in neurodegenerative diseases. Cell Mol Life Sci 2017; 74:683-695. [PMID: 27563707 PMCID: PMC11107737 DOI: 10.1007/s00018-016-2345-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 08/19/2016] [Accepted: 08/22/2016] [Indexed: 01/17/2023]
Abstract
Aptamers are small single-stranded DNA or RNA oligonucleotide fragments or small peptides, which can bind to targets by high affinity and specificity. Because aptamers are specific, non-immunogenic and non-toxic, they are ideal materials for clinical applications. Neurodegenerative disorders are ravaging the lives of patients. Even though the mechanism of these diseases is still elusive, they are mainly characterized by the accumulation of misfolded proteins in the central nervous system. So it is essential to develop potential measures to slow down or prevent the onset of these diseases. With the advancements of the technologies, aptamers have opened up new areas in this research field. Aptamers could bind with these related target proteins to interrupt their accumulation, subsequently blocking or preventing the process of neurodegenerative diseases. This review presents recent advances in the aptamer generation and its merits and limitations, with emphasis on its applications in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, transmissible spongiform encephalopathy, Huntington's disease and multiple sclerosis.
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Affiliation(s)
- Jing Qu
- Department of Neurobiology, Beijing Institute of Brain Disorders, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing Center of Neural Regeneration and Repair, Beijing Key Laboratory of Brain Major Disorders-State Key Lab Incubation Base, Beijing Neuroscience Disciplines, Capital Medical University, Beijing, 100069, China
| | - Shuqing Yu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, State Key Disciplinary of Neurosurgery Department, Capital Medical University, Beijing, 100050, China
| | - Yuan Zheng
- Department of Neurobiology, Beijing Institute of Brain Disorders, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing Center of Neural Regeneration and Repair, Beijing Key Laboratory of Brain Major Disorders-State Key Lab Incubation Base, Beijing Neuroscience Disciplines, Capital Medical University, Beijing, 100069, China
| | - Yan Zheng
- Department of Neurobiology, Beijing Institute of Brain Disorders, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing Center of Neural Regeneration and Repair, Beijing Key Laboratory of Brain Major Disorders-State Key Lab Incubation Base, Beijing Neuroscience Disciplines, Capital Medical University, Beijing, 100069, China
| | - Hui Yang
- Department of Neurobiology, Beijing Institute of Brain Disorders, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing Center of Neural Regeneration and Repair, Beijing Key Laboratory of Brain Major Disorders-State Key Lab Incubation Base, Beijing Neuroscience Disciplines, Capital Medical University, Beijing, 100069, China
| | - Jianliang Zhang
- Department of Neurobiology, Beijing Institute of Brain Disorders, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing Center of Neural Regeneration and Repair, Beijing Key Laboratory of Brain Major Disorders-State Key Lab Incubation Base, Beijing Neuroscience Disciplines, Capital Medical University, Beijing, 100069, China.
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Souza AG, Marangoni K, Fujimura PT, Alves PT, Silva MJ, Bastos VAF, Goulart LR, Goulart VA. 3D Cell-SELEX: Development of RNA aptamers as molecular probes for PC-3 tumor cell line. Exp Cell Res 2016; 341:147-56. [PMID: 26821206 DOI: 10.1016/j.yexcr.2016.01.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 01/22/2016] [Accepted: 01/24/2016] [Indexed: 10/25/2022]
Abstract
Human prostate cancer (PCa) is a highly heterogeneous and multifactorial disease. Current clinical biomarkers are not sufficiently accurate, thus being unable to predict the clinical outcome. Therefore, searching for new biomarkers aiming to improve diagnosis, prognosis and therapy is still required. In this study, we performed 3D Cell-SELEX against PC-3 prostate cancer cell line, a novel strategy to select specific nucleic acid ligands against spheroid cells in 3D cell culture. This original system combines Cell-SELEX, a process that exploits the cellular structure to generate specific ligands, and 3D cell culture, an approach that mimics the tissue microenvironment in vitro. In the first round of 3D Cell-SELEX, a negative selection against RWPE-1, non-tumor cell line, was performed to subtract non-tumor specific aptamers. The supernatant was used in eight additional rounds of selection, which were performed against PC-3 cell line. After nine selection cycles, eight PC-3 specific RNA aptamers were selected and sequenced. The aptamers presented sizes between 20 and 50 nucleotides-long, with low free energy (∆G<-13.6), which contributed for their spontaneous folding and high stability. Furthermore, our results showed the aptamer A4 as a specific ligand to prostate tumor cells, with dissociation constant in the nanomolar scale. Therefore, the novel 3D Cell-SELEX procedure improved the selection of PCa cell-surface ligands and the aptamer A4 has shown potential for the identification of prostate tumor cells, suggesting the application of this molecule in further screening assays for PCa.
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Affiliation(s)
- Aline G Souza
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil.
| | - Karina Marangoni
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil; Laboratory of Cancer Molecular Genetics, Faculty of Medical Sciences, University of Campinas, SP, Brazil
| | - Patrícia T Fujimura
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil
| | - Patrícia T Alves
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil
| | - Márcio J Silva
- Center of Molecular Biology and Genetic Engineering, University of Campinas, SP, Brazil
| | - Victor Alexandre F Bastos
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil
| | - Luiz R Goulart
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil; University of California-Davis, Department of Medical Microbiology and Immunology, Davis, CA, USA
| | - Vivian A Goulart
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia (UFU), 38400-902 Uberlândia, MG, Brazil
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20
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Inhibition of BACE1 Activity by a DNA Aptamer in an Alzheimer's Disease Cell Model. PLoS One 2015; 10:e0140733. [PMID: 26473367 PMCID: PMC4608735 DOI: 10.1371/journal.pone.0140733] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 09/28/2015] [Indexed: 02/07/2023] Open
Abstract
An initial step in amyloid-β (Aβ) production includes amyloid precursor protein (APP) cleavage via β-Site amyloid precursor protein cleaving enzyme 1 (BACE1). Increased levels of brain Aβ have been implicated in the pathogenesis of Alzheimer’s disease (AD). Thus, β-secretase represents a primary target for inhibitor drug development in AD. In this study, aptamers were obtained from combinatorial oligonucleotide libraries using a technology referred to as systematic evolution of ligands by exponential enrichment (SELEX). A purified human BACE1 extracellular domain was used as a target to conduct an in vitro selection process using SELEX. Two DNA aptamers were capable of binding to BACE1 with high affinity and good specificity, with Kd values in the nanomolar range. We subsequently confirmed that one aptamer, A1, exhibited a distinct inhibitory effect on BACE1 activity in an AD cell model. We detected the effects of M17-APPsw cells that stably expressed Swedish mutant APP after aptamer A1 treatment. Aβ40 and Aβ42 concentrations secreted by M17-APPsw cells decreased intracellularly and in culture media. Furthermore, Western blot analysis indicated that sAPPβ expression significantly decreased in the A1 treated versus control groups. These findings support the preliminary feasibility of an aptamer evolved from a SELEX strategy to function as a potential BACE1 inhibitor. To our knowledge, this is the first study to acquire a DNA aptamer that exhibited binding specificity to BACE1 and inhibited its activity.
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21
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McConnell EM, Holahan MR, DeRosa MC. Aptamers as promising molecular recognition elements for diagnostics and therapeutics in the central nervous system. Nucleic Acid Ther 2015; 24:388-404. [PMID: 25296265 DOI: 10.1089/nat.2014.0492] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Oligonucleotide aptamers are short, synthetic, single-stranded DNA or RNA able to recognize and bind to a multitude of targets ranging from small molecules to cells. Aptamers have emerged as valuable tools for fundamental research, clinical diagnosis, and therapy. Due to their small size, strong target affinity, lack of immunogenicity, and ease of chemical modification, aptamers are an attractive alternative to other molecular recognition elements, such as antibodies. Although it is a challenging environment, the central nervous system and related molecular targets present an exciting potential area for aptamer research. Aptamers hold promise for targeted drug delivery, diagnostics, and therapeutics. Here we review recent advances in aptamer research for neurotransmitter and neurotoxin targets, demyelinating disease and spinal cord injury, cerebrovascular disorders, pathologies related to protein aggregation (Alzheimer's, Parkinson's, and prions), brain cancer (glioblastomas and gliomas), and regulation of receptor function. Challenges and limitations posed by the blood brain barrier are described. Future perspectives for the application of aptamers to the central nervous system are also discussed.
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Affiliation(s)
- Erin M McConnell
- 1 Department of Chemistry, Carleton University , Ottawa, Ontario, Canada
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22
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Nucleic acid aptamers: research tools in disease diagnostics and therapeutics. BIOMED RESEARCH INTERNATIONAL 2014; 2014:540451. [PMID: 25050359 PMCID: PMC4090538 DOI: 10.1155/2014/540451] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 03/18/2014] [Indexed: 12/20/2022]
Abstract
Aptamers are short sequences of nucleic acid (DNA or RNA) or peptide molecules which adopt a conformation and bind cognate ligands with high affinity and specificity in a manner akin to antibody-antigen interactions. It has been globally acknowledged that aptamers promise a plethora of diagnostic and therapeutic applications. Although use of nucleic acid aptamers as targeted therapeutics or mediators of targeted drug delivery is a relatively new avenue of research, one aptamer-based drug “Macugen” is FDA approved and a series of aptamer-based drugs are in clinical pipelines. The present review discusses the aspects of design, unique properties, applications, and development of different aptamers to aid in cancer diagnosis, prevention, and/or treatment under defined conditions.
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Germer K, Leonard M, Zhang X. RNA aptamers and their therapeutic and diagnostic applications. INTERNATIONAL JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 4:27-40. [PMID: 23638319 PMCID: PMC3627066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 02/15/2013] [Indexed: 06/02/2023]
Abstract
RNA Aptamers refer to RNA oligonulceotides that are capable of binding to specific targets with high affinity and specificity. Through a process called Systematic Evolution of Ligands by EXponential enrichment (SELEX), a number of RNA aptamers have been identified against various targets including organic compounds, nucleotides, proteins and even whole cells and organisms. RNA aptamers have proven to be of high therapeutic and diagnostic value with recent FDA approval of the first aptamer drug and additional ones in the clinical pipelines. It has also been found to be a particularly useful tool for cell-type specific delivery of other RNA therapeutics like siRNA. All these establish RNA aptamers as one of the pivotal tools of the emerging RNA nanotechnology field in the fight against human diseases including cancer, viral infections and other diseases. This article summarizes the current advancement in the identification of RNA aptamers and also provides some examples of their therapeutic and diagnostic applications.
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Affiliation(s)
- Katherine Germer
- Department of Cancer Biology, Vontz Center for Molecular Studies, University of Cincinnati College of Medicine OH 45267
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24
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Zhou J, Bobbin ML, Burnett JC, Rossi JJ. Current progress of RNA aptamer-based therapeutics. Front Genet 2012; 3:234. [PMID: 23130020 PMCID: PMC3486975 DOI: 10.3389/fgene.2012.00234] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 10/15/2012] [Indexed: 01/07/2023] Open
Abstract
Aptamers are single-stranded nucleic acids that specifically recognize and bind tightly to their cognate targets due to their stable three-dimensional structure. Nucleic acid aptamers have been developed for various applications, including diagnostics, molecular imaging, biomarker discovery, target validation, therapeutics, and drug delivery. Due to their high specificity and binding affinity, aptamers directly block or interrupt the functions of target proteins making them promising therapeutic agents for the treatment of human maladies. Additionally, aptamers that bind to cell surface proteins are well suited for the targeted delivery of other therapeutics, such as conjugated small interfering RNAs (siRNA) that induce RNA interference (RNAi). Thus, aptamer-siRNA chimeras may offer dual-functions, in which the aptamer inhibits a receptor function, while the siRNA internalizes into the cell to target a specific mRNA. This review focuses on the current progress and therapeutic potential of RNA aptamers, including the use of cell-internalizing aptamers as cell-type specific delivery vehicles for targeted RNAi. In particular, we discuss emerging aptamer-based therapeutics that provide unique clinical opportunities for the treatment various cancers and neurological diseases.
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Affiliation(s)
- Jiehua Zhou
- Division of Molecular and Cellular Biology, Beckman Research Institute of City of Hope Duarte, CA, USA
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25
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Mathew A, Aravind A, Brahatheeswaran D, Fukuda T, Nagaoka Y, Hasumura T, Iwai S, Morimoto H, Yoshida Y, Maekawa T, Venugopal K, Kumar DS. Amyloid-Binding Aptamer Conjugated Curcumin–PLGA Nanoparticle for Potential Use in Alzheimer’s Disease. BIONANOSCIENCE 2012. [DOI: 10.1007/s12668-012-0040-y] [Citation(s) in RCA: 18] [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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Rohrbach F, Fatthalla MI, Kupper T, Pötzsch B, Müller J, Petersen M, Pedersen EB, Mayer G. Chemical maturation of a bivalent aptamer by single domain variation. Chembiochem 2012; 13:631-4. [PMID: 22331608 DOI: 10.1002/cbic.201200015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/1932] [Indexed: 01/28/2023]
Affiliation(s)
- Falk Rohrbach
- Life and Medical Sciences Institute, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
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27
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Holahan MR, Madularu D, McConnell EM, Walsh R, DeRosa MC. Intra-accumbens injection of a dopamine aptamer abates MK-801-induced cognitive dysfunction in a model of schizophrenia. PLoS One 2011; 6:e22239. [PMID: 21779401 PMCID: PMC3135623 DOI: 10.1371/journal.pone.0022239] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 06/16/2011] [Indexed: 11/18/2022] Open
Abstract
Systemic administration of the noncompetitive NMDA-receptor antagonist, MK-801, has been proposed to model cognitive deficits similar to those seen in patients with schizophrenia. The present work investigated the ability of a dopamine-binding DNA aptamer to regulate these MK-801-induced cognitive deficits when injected into the nucleus accumbens. Rats were trained to bar press for chocolate pellet rewards then randomly assigned to receive an intra-accumbens injection of a DNA aptamer (200 nM; n = 7), tris buffer (n = 6) or a randomized DNA oligonucleotide (n = 7). Animals were then treated systemically with MK-801 (0.1 mg/kg) and tested for their ability to extinguish their bar pressing response. Two control groups were also included that did not receive MK-801. Data revealed that injection of Tris buffer or the random oligonucleotide sequence into the nucleus accumbens prior to treatment with MK-801 did not reduce the MK-801-induced extinction deficit. Animals continued to press at a high rate over the entire course of the extinction session. Injection of the dopamine aptamer reversed this MK-801-induced elevation in lever pressing to levels as seen in rats not treated with MK-801. Tests for activity showed that the aptamer did not impair locomotor activity. Results demonstrate the in vivo utility of DNA aptamers as tools to investigate neurobiological processes in preclinical animal models of mental health disease.
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Affiliation(s)
- Matthew R. Holahan
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
- * E-mail: (MRH); (MD)
| | - Dan Madularu
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Erin M. McConnell
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
| | - Ryan Walsh
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
| | - Maria C. DeRosa
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
- * E-mail: (MRH); (MD)
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29
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Abstract
Aptamers that target a specific cell subpopulation within composite mixtures represent invaluable tools in biomedical research and in the development of cell-specific therapeutics. Here we describe a detailed protocol for a modular and generally applicable scheme to select aptamers that target the subpopulations of cells in which you are interested. A fluorescence-activated cell-sorting device is used to simultaneously differentiate and separate those subpopulations of cells having bound and unbound aptamers. There are fewer false positives when using this approach in comparison with other cell-selection approaches in which unspecific binding of nucleic acids to cells with reduced membrane integrity or their unselective uptake by dead cells occurs more often. The protocol provides a state-of-the-art approach for identifying aptamers that selectively target virtually any cell type under investigation. As an example, we provide the step-by-step protocol targeting CD19(+) Burkitt's lymphoma cells, starting from the pre-SELEX (systematic evolution of ligands by exponential amplification) measurements to establish suitable SELEX conditions and ending at completion of the SELEX procedure, which reveals the enriched single-stranded DNA library.
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30
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Abstract
The clinical potential of siRNAs for silencing genes critical to disease progression is clear, but a fail-proof method for delivering siRNAs to the cytoplasm of diseased tissues or cells has yet to be identified. A variety of delivery approaches have been explored to directly or indirectly couple siRNAs to delivery vehicles. This review explores the use of synthetic single-stranded DNA and RNA aptamers as a means to deliver siRNAs, shRNAs and antisense oligonucleotides for therapeutic intervention. Topics covered include: the advantages and challenges of using aptamers as delivery tools; current aptamer-mediated siRNA delivery platforms for the treatment of cancer and HIV; and emerging methodologies for the identification of aptamers capable of internalizing into target cell types.
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Affiliation(s)
- Kristina W Thiel
- Department of Internal Medicine, Department of Radiation Oncology, 375 Newton Rd, 5202 MERF, Iowa City, IA 52242, USA
| | - Paloma H Giangrande
- Department of Internal Medicine, Department of Radiation Oncology, 375 Newton Rd, 5202 MERF, Iowa City, IA 52242, USA
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31
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Siepmann M, Kumar S, Mayer G, Walter J. Casein kinase 2 dependent phosphorylation of neprilysin regulates receptor tyrosine kinase signaling to Akt. PLoS One 2010; 5. [PMID: 20957047 PMCID: PMC2948513 DOI: 10.1371/journal.pone.0013134] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 09/05/2010] [Indexed: 11/18/2022] Open
Abstract
Neprilysin (NEP) is a type II membrane metalloproteinase that cleaves physiologically active peptides at the cell surface thus regulating the local concentration of these peptides available for receptor binding and signal transduction. In addition, the cytoplasmic N-terminal domain of NEP interacts with the phosphatase and tensin homologue deleted on chromosome 10 (PTEN) thereby regulating intracellular signaling via Akt. Thus, NEP serves dual functions in extracellular and intracellular signal transduction. Here, we show that NEP undergoes phosphorylation at serine residue 6 within the N-terminal cytoplasmic domain. In vitro and cell culture experiments demonstrate that Ser 6 is efficiently phosphorylated by protein kinase CK2. The phosphorylation of the cytoplasmic domain of NEP inhibits its interaction with PTEN. Interestingly, expression of a pseudophosphorylated NEP variant (Ser6Asp) abrogates the inhibitory effect of NEP on insulin/insulin-like growth factor-1 (IGF-1) stimulated activation of Akt. Thus, our data demonstrate a regulatory role of CK2 in the interaction of NEP with PTEN and insulin/IGF-1 signaling.
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Affiliation(s)
- Martin Siepmann
- Department of Neurology, Molecular Cell Biology, University of Bonn, Bonn, Germany
| | - Sathish Kumar
- Department of Neurology, Molecular Cell Biology, University of Bonn, Bonn, Germany
| | - Günter Mayer
- Limes-Institute, Chemical Biology c/o Kekulé-Institute for Organic Chemistry and Biochemistry, University of Bonn, Bonn, Germany
| | - Jochen Walter
- Department of Neurology, Molecular Cell Biology, University of Bonn, Bonn, Germany
- * E-mail:
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Davis AR, Znosko BM. Positional and neighboring base pair effects on the thermodynamic stability of RNA single mismatches. Biochemistry 2010; 49:8669-79. [PMID: 20681613 DOI: 10.1021/bi100146z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Many naturally occurring RNA structures contain single mismatches, many of which occur near the ends of helices. However, previous thermodynamic studies have focused their efforts on thermodynamically characterizing centrally placed single mismatches. Additionally, algorithms currently used to predict secondary structure from sequence are based on two assumptions for predicting the stability of RNA duplexes containing this motif. It has been assumed that the thermodynamic contribution of small RNA motifs is independent of both its position in the duplex and the identity of the non-nearest neighbors. Thermodynamically characterizing single mismatches three nucleotides from both the 3' and 5' ends (i.e., off-center) of an RNA duplex and comparing these results to those of the same single mismatch-nearest neighbor combination centrally located have allowed for the investigation of these effects. The thermodynamic contributions of 13 single mismatch-nearest neighbor combinations are reported, but only nine combinations are studied at all three duplex positions and are used to determine trends and patterns. In general, the 5'- and 3'-shifted single mismatches are relatively similar, on average, and more favorable in free energy than centrally placed single mismatches. However, close examination and comparison shows there are several associated idiosyncrasies with these identified general trends. These peculiarities may be due, in part, to the identities of the single mismatch, the nearest neighbors, and the non-nearest neighbors, along with the effects of the single mismatch position in the duplex. The prediction algorithm recently proposed by Davis and Znosko [Davis, A. R., and Znosko, B. M. (2008) Biochemistry 47, 10178-10187] is used to predict the thermodynamic parameters of single mismatch contribution, and those values are compared to the measured values presented here. This comparison suggests the proposed model is a good approximation but could be improved by the addition of parameters that account for positional and/or non-nearest neighbor effects. However, more data are required to improve our understanding of these effects and to accurately account for them.
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Affiliation(s)
- Amber R Davis
- Department of Chemistry, Saint Louis University, Saint Louis, Missouri 63103, USA
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The selection of aptamers specific for membrane molecular targets. Cell Mol Biol Lett 2010; 16:25-39. [PMID: 20585890 PMCID: PMC6275783 DOI: 10.2478/s11658-010-0023-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2009] [Accepted: 06/14/2010] [Indexed: 02/07/2023] Open
Abstract
A growing number of RNA aptamers have been selected experimentally using the SELEX combinatorial approach, and these aptamers have several advantages over monoclonal protein antibodies or peptides with respect to their applications in medicine and nanobiotechnology. Relatively few successful selections have been reported for membrane molecular targets, in contrast to the situation with non-membrane molecular targets. This review compares the procedures and techniques used in selections against membrane proteins and membrane lipids. In the case of membrane proteins, the selections were performed against soluble protein fragments, detergent-membrane protein mixed micelles, whole cells, vesicles derived from cellular membranes, and enveloped viruses. Liposomes were used as an experimental system for the selection of aptamers against membrane lipids. RNA structure-dependent aptamer binding for rafts in lipid vesicles was reported. Based on the selected aptamers against DOPC and the amino acid tryptophan, a specific passive membrane transporter composed of RNA was constructed. The determination of the selectivity of aptamers appears to be a crucial step in a selection, but has rarely been fully investigated. The selections, which use whole cells or vesicles derived from membranes, can yield aptamers not only against proteins but also against membrane lipids.
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Wang Y, Khaing ZZ, Li N, Hall B, Schmidt CE, Ellington AD. Aptamer antagonists of myelin-derived inhibitors promote axon growth. PLoS One 2010; 5:e9726. [PMID: 20300533 PMCID: PMC2838799 DOI: 10.1371/journal.pone.0009726] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Accepted: 02/22/2010] [Indexed: 11/18/2022] Open
Abstract
Myelin of the adult central nervous system (CNS) is one of the major sources of inhibitors of axon regeneration following injury. The three known myelin-derived inhibitors (Nogo, MAG, and OMgp) bind with high affinity to the Nogo-66 receptor (NgR) on axons and limit neurite outgrowth. Here we show that RNA aptamers can be generated that bind with high affinity to NgR, compete with myelin-derived inhibitors for binding to NgR, and promote axon elongation of neurons in vitro even in the presence of these inhibitors. Aptamers may have key advantages over protein antagonists, including low immunogenicity and the possibility of ready modification during chemical synthesis for stability, signaling, or immobilization. This first demonstration that aptamers can directly influence neuronal function suggests that aptamers may prove useful for not only healing spinal cord and other neuronal damage, but may be more generally useful as neuromodulators.
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Affiliation(s)
- Yuxuan Wang
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas, United States of America
| | - Zin Z. Khaing
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, United States of America
| | - Na Li
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas, United States of America
| | - Brad Hall
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas, United States of America
| | - Christine E. Schmidt
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, United States of America
- Department of Chemical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, Texas, United States of America
| | - Andrew D. Ellington
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas, United States of America
- * E-mail:
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Lutsenko S, Bhattacharjee A, Hubbard AL. Copper handling machinery of the brain. Metallomics 2010; 2:596-608. [DOI: 10.1039/c0mt00006j] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Affiliation(s)
- Michael Famulok
- LIMES Program Unit Chemical Biology and Medicinal Chemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany.
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Thiel KW, Giangrande PH. Therapeutic applications of DNA and RNA aptamers. Oligonucleotides 2009; 19:209-22. [PMID: 19653880 DOI: 10.1089/oli.2009.0199] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Structured single-stranded nucleic acids, or aptamers, bind target molecules with high affinity and specificity, which translates into unique therapeutic possibilities. Currently, aptamers can be identified to most proteins, including blood-clotting factors, cell-surface receptors, and transcription factors. Chemical modifications to the oligonucleotides enhance their pharmacokinetics and pharmacodynamics, thus extending their therapeutic potential. Several aptamers have entered the clinical pipeline for applications and diseases such as macular degeneration, coronary artery bypass graft surgery, and various types of cancer. Furthermore, the functional repertoire of aptamers has expanded with the descriptions of multivalent agonistic aptamers and aptamers-siRNA chimeras. This review highlights those aptamers and aptamer-based approaches with particular likelihood of achieving therapeutic application.
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Affiliation(s)
- Kristina W Thiel
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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Yamin G, Ono K, Inayathullah M, Teplow DB. Amyloid beta-protein assembly as a therapeutic target of Alzheimer's disease. Curr Pharm Des 2009; 14:3231-46. [PMID: 19075703 DOI: 10.2174/138161208786404137] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Alzheimer's disease (AD), the most common neurodegenerative disorder in the aged, is characterized by the cerebral deposition of fibrils formed by the amyloid beta-protein (Abeta), a 40-42 amino acid peptide. The folding of Abeta into neurotoxic oligomeric, protofibrillar, and fibrillar assemblies is hypothesized to be the key pathologic event in AD. Abeta is formed through cleavage of the Abeta precursor protein by two endoproteinases, beta-secretase and gamma-secretase, that cleave the Abeta N-terminus and C-terminus, respectively. These facts support the relevance of therapeutic strategies targeting Abeta production, assembly, clearance, and neurotoxicity. Currently, no disease-modifying therapeutic agents are available for AD patients. Instead, existing therapeutics provide only modest symptomatic benefits for a limited time. We summarize here recent efforts to produce therapeutic drugs targeting Abeta assembly. A number of approaches are being used in these efforts, including immunological, nutraceutical, and more classical medicinal chemical (peptidic inhibitors, carbohydrate-containing compounds, polyamines, "drug-like" compounds, chaperones, metal chelators, and osmolytes), and many of these have progressed to phase III clinical trails. We also discuss briefly a number of less mature, but intriguing, strategies that have therapeutic potential. Although initial trials of some disease-modifying agents have failed, we argue that substantial cause for optimism exists.
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Affiliation(s)
- Ghiam Yamin
- Department of Neurology, David Geffen School of Medicine at UCLA, 635 Charles E. Young Drive South (Room 445), Los Angeles, California 90095, USA
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Liu Y, Sun QA, Chen Q, Lee TH, Huang Y, Wetsel WC, Michelotti GA, Sullenger BA, Zhang X. Targeting inhibition of GluR1 Ser845 phosphorylation with an RNA aptamer that blocks AMPA receptor trafficking. J Neurochem 2008; 108:147-57. [PMID: 19046328 DOI: 10.1111/j.1471-4159.2008.05748.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Phosphorylation at glutamate receptor subunit 1(GluR1) Ser845 residue has been widely accepted to involve in GluR1-containing alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor trafficking, but the in vivo evidence has not yet been established. One of the main obstacles is the lack of effective methodologies to selectively target phosphorylation at single amino acid residue. In this study, the Escherichia coli-expressed glutathione-S-transferase-tagged intracellular carboxyl-terminal domain of GluR1 (cGluR1) was phosphorylated by protein kinase A for in vitro selection. We have successfully selected aptamers which effectively bind to phospho-Ser845 cGluR1 protein, but without binding to phospho-Ser831 cGluR1 protein. Moreover, pre-binding of the unphospho-cGluR1 protein with these aptamers inhibits protein kinase A-mediated phosphorylation at Ser845 residue. In contrast, the pre-binding of aptamer A2 has no effect on protein kinase C-mediated phosphorylation at Ser831 residue. Importantly, the representative aptamer A2 can effectively bind the mammalian GluR1 that inhibited GluR1/GluR1-containing AMPA receptor trafficking to the cell surface and abrogated forskolin-stimulated phosphorylation at GluR1 Ser845 in both green fluorescent protein-GluR1-transfected human embryonic kidney cells and cultured rat cortical neurons. The strategy to use aptamer to modify single-residue phosphorylation is expected to facilitate evaluation of the potential role of AMPA receptors in various forms of synaptic plasticity including that underlying psychostimulant abuse.
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Affiliation(s)
- Yingmiao Liu
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
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Rentmeister A, Mayer G, Kuhn N, Famulok M. Secondary structures and functional requirements for thiM riboswitches from Desulfovibrio vulgaris, Erwinia carotovora and Rhodobacter spheroides. Biol Chem 2008; 389:127-34. [PMID: 18163882 DOI: 10.1515/bc.2008.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Abstract Bacterial thiM riboswitches contain aptamer domains that bind the metabolite thiamine pyrophosphate (TPP). Binding of TPP to the aptamer domain induces structural rearrangements that are relayed to the expression domain, thereby interfering with gene expression. Here, we report identification of three putative thiM riboswitches from different bacteria and analysis of their secondary structures. Chemical probing revealed that the riboswitches share similar secondary structures in their aptamer domains that can communicate with the highly variant expression domains in a mechanism likely involving sequestration of the Shine-Dalgarno sequence. Remarkably, the aptamer domain of the thiM gene of Desulfovibrio vulgaris binds TPP with similar affinity and selectivity as that of Escherichia coli, although nucleotides previously shown to form direct contacts to the metabolite are mutated. We also designed small RNA hairpins for each riboswitch that bind the RNA only in the absence of the metabolite. Our study shows that aptamer domains in riboswitches with high similarity in their secondary structures can communicate with a broad variety of non-related expression domains by similar mechanisms.
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Affiliation(s)
- Andrea Rentmeister
- LIMES-Institute, Program Unit Chemical Biology and Medicinal Chemistry, c/o Kekulé-Institute for Organic Chemistry and Biochemistry of the University of Bonn, Gerhard-Domagk-Strasse 1, D-53121 Bonn, Germany
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Knieps M, Herrmann S, Lehmann C, Löer B, Hoch M, Famulok M. Anti-innexin 2 aptamers specifically inhibit the heterologous interaction of the innexin 2 and innexin 3 carboxyl-termini in vitro. Biol Chem 2007; 388:561-8. [PMID: 17552903 DOI: 10.1515/bc.2007.074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We recently demonstrated that heteromerization of innexins 2 and 3 from Drosophila melanogaster (Dm) is crucial for epithelial organization and polarity of the embryonic epidermis. Both innexins are thought to interact via their C-terminal cytoplasmic domains during the assembly of heteromeric gap junction channels. However, the mechanisms that control heteromeric versus homomeric channel formation are still largely unknown. Here we report the isolation of both non-modified and 2'-fluoro-2'-deoxy-modified RNA anti-innexin 2 aptamers by in vitro selection. The aptamers bind to a proximal epitope on the carboxyl-tail of Dm innexin 2 protein and specifically inhibit the heterologous interaction of innexin 2 and innexin 3 carboxyl-termini in vitro. These domain-specific inhibitors represent the first step towards functional studies focusing on the activity of these domains in vivo.
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Affiliation(s)
- Martin Knieps
- LIMES Institute, Program Unit Chemical Biology and Medicinal Chemistry, c/o Kekulé Institute for Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, D-53121 Bonn, Germany
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Yang X, Yang Y, Wu J, Zhu J. Stable Expression of a Novel Fusion Peptide of Thioredoxin-1 and ABAD-Inhibiting Peptide Protects PC12 Cells from Intracellular Amyloid-Beta. J Mol Neurosci 2007; 33:180-8. [DOI: 10.1007/s12031-007-0063-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2007] [Revised: 11/30/1999] [Accepted: 06/27/2007] [Indexed: 11/28/2022]
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Yang Y, Yang D, Schluesener HJ, Zhang Z. Advances in SELEX and application of aptamers in the central nervous system. ACTA ACUST UNITED AC 2007; 24:583-92. [PMID: 17681489 DOI: 10.1016/j.bioeng.2007.06.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 06/12/2007] [Accepted: 06/13/2007] [Indexed: 11/22/2022]
Abstract
SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is a screening technique that involves the progressive selection of highly specific ligands by repeated rounds of partition and amplification from a large combinatorial nucleic acid library. The products of the selection are called aptamers, which are short single stranded DNA or RNA molecules, binding with high affinity, attributed to their specific three-dimensional shapes, to a large variety of targets, ranging from small molecules to complex mixtures. Various improvement of the original SELEX method described in 1990 have been obtained recently, such as capillary electrophoresis SELEX, Toggle-SELEX, Tailored-SELEX, Photo-SELEX, and others. These new variants greatly shorten time of selection and improve aptamer affinity and specificity. Such aptamers have great potential as detecting and/or diagnostic reagents. Furthermore, some aptamers specifically inhibit biological functions of targeted proteins, and are considered as potent therapeutic lead structures evaluated in preclinical disease models. Recently, one aptamer has been approved by Food and Drug Administration of US for treating age-related macular degeneration. This review presents recent advances in the field of SELEX with special emphasis on applications of aptamers as analytical, diagnostic and therapeutic tools in the central nervous system.
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Affiliation(s)
- Yan Yang
- Experimental Medical Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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Rentmeister A, Mayer G, Kuhn N, Famulok M. Conformational changes in the expression domain of the Escherichia coli thiM riboswitch. Nucleic Acids Res 2007; 35:3713-22. [PMID: 17517779 PMCID: PMC1920254 DOI: 10.1093/nar/gkm300] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The thiM riboswitch contains an aptamer domain that adaptively binds the coenzyme thiamine pyrophosphate (TPP). The binding of TPP to the aptamer domain induces structural rearrangements that are relayed to a second domain, the so-called expression domain, thereby interfering with gene expression. The recently solved crystal structures of the aptamer domains of the thiM riboswitches in complex with TPP revealed how TPP stabilizes secondary and tertiary structures in the RNA ligand complex. To understand the global modes of reorganization between the two domains upon metabolite binding the structure of the entire riboswitch in presence and absence of TPP needs to be determined. Here we report the secondary structure of the entire thiM riboswitch from Escherichia coli in its TPP-free form and its transition into the TPP-bound variant, thereby depicting domains of the riboswitch that serve as communication links between the aptamer and the expression domain. Furthermore, structural probing provides an explanation for the lack of genetic control exerted by a riboswitch variant with mutations in the expression domain that still binds TPP.
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Affiliation(s)
| | | | | | - Michael Famulok
- *To whom correspondence should be addressed. +49-228-735661+49-228-735388
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45
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Rich RL, Myszka DG. Survey of the year 2006 commercial optical biosensor literature. J Mol Recognit 2007; 20:300-66. [DOI: 10.1002/jmr.862] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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