1
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Tamaddon-Abibigloo Y, Dastmalchi S, Razzaghi-Asl N, Shahbazi Mojarrad J. Design, synthesis, in vitro and in silico evaluations of new isatin-triazine- aniline hybrids as potent anti- Alzheimer multi-target directed lead compounds. Bioorg Chem 2024; 147:107355. [PMID: 38657528 DOI: 10.1016/j.bioorg.2024.107355] [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: 12/09/2023] [Revised: 03/19/2024] [Accepted: 04/06/2024] [Indexed: 04/26/2024]
Abstract
Multi target directed ligands (MTDLs) are one of the promising tools for treatment of complex disease like Alzheimer's disease (AD). In this study, using rational design, we synthesized new 15 hybrids of the s-triazine, isatin and aniline derivatives as anti- AD compounds. The design was as way as that new compounds could had anti cholinesterase (ChE), antioxidant and biometal chelation ability. In vitro biological evaluation against ChE enzymes showed that these molecules were excellent inhibitors with IC50 values ranging from 0.2 nM to 734.5 nM for acetylcholinesterase (AChE), and 0.02 μM to 1.92 μM for butyrylcholinesterase (BChE). Among these compounds, 8 l with IC50 AChE = 0.7 nM, IC50 BChE = 0.09 μM and 8n with IC50 AChE = 0.2 nM, IC50 BChE = 0.03 μM were the most potent compounds. In silico studies showed that these molecules had key and effective interactions with the corresponding enzymes residues. The molecules with hydroxyl group on aniline moiety had also good antioxidant activity with EC50 values ranging from 64.2 μM to 103.6 μM. The UV-Vis spectroscopy study revealed that molecule 8n was also able to chelate biometals such as Zn2+, Cu2+and Fe2+ properly. It was concluded that these molecules could be excellent lead compounds for future studies.
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Affiliation(s)
- Yasaman Tamaddon-Abibigloo
- Department of Medicinal Chemistry, School of pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Siavoush Dastmalchi
- Department of Medicinal Chemistry, School of pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Pharmacy, Near East University, Nicosia, North Cyprus, Turkey
| | - Nima Razzaghi-Asl
- Department of Medicinal Chemistry, School of Pharmacy, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Javid Shahbazi Mojarrad
- Department of Medicinal Chemistry, School of pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
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2
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Jiao L, Jing Z, Zhang W, Su X, Yan H, Tian S. Codon Pattern and Context Analysis in Genes Triggering Alzheimer's Disease and Latent Tau Protein Aggregation Post-Anesthesia Exhibited Unique Molecular Patterns Associated with Functional Aspects. J Alzheimers Dis 2024; 97:1645-1660. [PMID: 38306048 DOI: 10.3233/jad-231142] [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] [Indexed: 02/03/2024]
Abstract
Background Previous reports have demonstrated post-operative dementia and Alzheimer's disease (AD), and increased amyloid-β levels and tau hyperphosphorylation have been observed in animal models post-anesthesia. Objective After surgical interventions, loss in memory has been observed that has been found linked with genes modulated after anesthesia. Present study aimed to study molecular pattern present in genes modulated post anesthesia and involved in characters progressing towards AD. Methods In the present study, 17 transcript variants belonging to eight genes, which have been found to modulate post-anesthesia and contribute to AD progression, were envisaged for their compositional features, molecular patterns, and codon and codon context-associated studies. Results The sequences' composition was G/C rich, influencing dinucleotide preference, codon preference, codon usage, and codon context. The G/C nucleotides being highly occurring nucleotides, CpGdinucleotides were also preferred; however, CpG was highly disfavored at p3-1 at the codon junction. The nucleotide composition of Cytosine exhibited a unique feature, and unlike other nucleotides, it did not correlate with codon bias. Contrarily, it correlated with the sequence lengths. The sequences were leucine-rich, and multiple leucine repeats were present, exhibiting the functional role of neuroprotection from neuroinflammation post-anesthesia. Conclusions The analysis pave the way to elucidate unique molecular patterns in genes modulated during anesthetic treatment and might help ameliorate the ill effects of anesthetics in the future.
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Affiliation(s)
- Liyuan Jiao
- Department of Anesthesiology, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Ziye Jing
- Department of Anesthesiology, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Wenjie Zhang
- Department of Anesthesiology, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Xuesen Su
- Department of Anesthesiology, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Hualei Yan
- Department of Anesthesiology, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Shouyuan Tian
- Shanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences, Taiyuan, China
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3
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Do HTT, Cho J. Mangosteen Pericarp and Its Bioactive Xanthones: Potential Therapeutic Value in Alzheimer's Disease, Parkinson's Disease, and Depression with Pharmacokinetic and Safety Profiles. Int J Mol Sci 2020; 21:E6211. [PMID: 32867357 PMCID: PMC7504283 DOI: 10.3390/ijms21176211] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/22/2020] [Accepted: 08/25/2020] [Indexed: 12/11/2022] Open
Abstract
Alzheimer's disease (AD), Parkinson's disease (PD), and depression are growing burdens for society globally, partly due to a lack of effective treatments. Mangosteen (Garcinia mangostana L.,) pericarp (MP) and its xanthones may provide therapeutic advantages for these disorders. In this review, we discuss potential therapeutic value of MP-derived agents in AD, PD, and depression with their pharmacokinetic and safety profiles. MP-derived agents have shown multifunctional effects including neuroprotective, antioxidant, and anti-neuroinflammatory actions. In addition, they target specific disease pathologies, such as amyloid beta production and deposition as well as cholinergic dysfunction in AD; α-synuclein aggregation in PD; and modulation of monoamine disturbance in depression. Particularly, the xanthone derivatives, including α-mangostin and γ-mangostin, exhibit potent pharmacological actions. However, low oral bioavailability and poor brain penetration may limit their therapeutic applications. These challenges can be overcome in part by administering as a form of MP extract (MPE) or using specific carrier systems. MPE and α-mangostin are generally safe and well-tolerated in animals. Furthermore, mangosteen-based products are safe for humans. Therefore, MPE and its bioactive xanthones are promising candidates for the treatment of AD, PD, and depression. Further studies including clinical trials are essential to decipher their efficacy, and pharmacokinetic and safety profiles in these disorders.
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Affiliation(s)
| | - Jungsook Cho
- College of Pharmacy, Dongguk University-Seoul, Dongguk-ro 32, Ilsandong-gu, Goyang, Gyeonggi 10326, Korea;
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4
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Therapeutic Potential of Direct Clearance of the Amyloid-β in Alzheimer's Disease. Brain Sci 2020; 10:brainsci10020093. [PMID: 32050618 PMCID: PMC7071829 DOI: 10.3390/brainsci10020093] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/05/2020] [Accepted: 02/05/2020] [Indexed: 12/19/2022] Open
Abstract
Alzheimer’s disease (AD) is characterized by deposition and accumulation of amyloid-β (Aβ) and its corresponding plaques within the brain. Although much debate exists whether these plaques are the cause or the effect of AD, the accumulation of Aβ is linked with the imbalance between the production and clearance of Aβ. The receptor for advanced glycation endproducts (RAGE) facilitates entry of free Aβ from the peripheral stream. Conversely, lipoprotein receptor-related protein 1 (LRP1), located in the abluminal side at the blood–brain barrier mediates the efflux of Aβ. Research on altering the rates of clearance of Aβ by targeting these two pathways has been extensively study. Additionally, a cerebrospinal fluid (CSF) circulation assistant device has also been evaluated as an approach to increase solute concentration in the CSF via mechanical drainage, to allow for removal of Aβ from the brain. Herein, we provide a brief review of these approaches that are designed to re-establish a homeostatic Aβ balance in the brain.
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5
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Kapadia A, Patel A, Sharma KK, Maurya IK, Singh V, Khullar M, Jain R. Effect of C-terminus amidation of Aβ39–42fragment derived peptides as potential inhibitors of Aβ aggregation. RSC Adv 2020; 10:27137-27151. [PMID: 35515767 PMCID: PMC9055537 DOI: 10.1039/d0ra04788k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 07/10/2020] [Indexed: 11/21/2022] Open
Abstract
The C-terminus fragment (Val-Val-Ile-Ala) of amyloid-β is reported to inhibit the aggregation of the parent peptide. In an attempt to investigate the effect of sequential amino-acid scan and C-terminus amidation on the biological profile of the lead sequence, a series of tetrapeptides were synthesized using MW-SPPS. Peptide D-Phe-Val-Ile-Ala-NH2 (12c) exhibited high protection against β-amyloid-mediated-neurotoxicity by inhibiting Aβ aggregation in the MTT cell viability and ThT-fluorescence assay. Circular dichroism studies illustrate the inability of Aβ42 to form β-sheet in the presence of 12c, further confirmed by the absence of Aβ42 fibrils in electron microscopy experiments. The peptide exhibits enhanced BBB permeation, no cytotoxicity along with prolonged proteolytic stability. In silico studies show that the peptide interacts with the key amino acids in Aβ, which potentiate its fibrillation, thereby arresting aggregation propensity. This structural class of designed scaffolds provides impetus towards the rational development of peptide-based-therapeutics for Alzheimer's disease (AD). Amidated C-terminal fragment, Aβ39–42 derived non-cytotoxic β-sheet breaker peptides exhibit excellent potency, enhanced bioavailability and improved proteolytic stability.![]()
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Affiliation(s)
- Akshay Kapadia
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research
- India
| | - Aesan Patel
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research
- India
| | - Krishna K. Sharma
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research
- India
| | | | - Varinder Singh
- Post Graduate Institute of Medical Education and Research
- Chandigarh
- India
| | - Madhu Khullar
- Post Graduate Institute of Medical Education and Research
- Chandigarh
- India
| | - Rahul Jain
- Department of Medicinal Chemistry
- National Institute of Pharmaceutical Education and Research
- India
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6
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Kuo YC, Rajesh R. Challenges in the treatment of Alzheimer’s disease: recent progress and treatment strategies of pharmaceuticals targeting notable pathological factors. Expert Rev Neurother 2019; 19:623-652. [DOI: 10.1080/14737175.2019.1621750] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Yung-Chih Kuo
- Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan, Republic of China
| | - Rajendiran Rajesh
- Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan, Republic of China
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7
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Thai NQ, Bednarikova Z, Gancar M, Linh HQ, Hu CK, Li MS, Gazova Z. Compound CID 9998128 Is a Potential Multitarget Drug for Alzheimer's Disease. ACS Chem Neurosci 2018; 9:2588-2598. [PMID: 29775277 DOI: 10.1021/acschemneuro.8b00091] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We have probed small molecule compound CID 9998128 as a potential multitarget drug for the Alzheimer's disease (AD) using in silico and in vitro experiments. By all-atom simulation and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method, we have demonstrated that this compound strongly binds to both amyloid β42 (Aβ42) fibrils and β-secretase, and the van der Waals interaction dominates over the electrostatic interaction in binding affinity. A detailed analysis at the atomic level revealed that indazole in CID 99998128 structure made a major contribution to instability of all studied complexes. In vitro experiments have shown that CID 9998128 inhibits the Aβ42 amyloid fibrillization and is capable to clear Aβ42 fibrils. Moreover, the compound dose-dependently decreases β-site amyloid precursor protein cleaving enzyme (BACE-1) activity with EC50 value in micromolar range. Thus, our study has revealed that CID 9998128 is a good candidate for AD treatment through preventing production of Aβ peptides and degrading their aggregates. For drug design, we predict that the chemical structure of potent AD multitarget inhibitors should not contain indazole.
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Affiliation(s)
- Nguyen Quoc Thai
- Institute for Computational Sciences and Technology, SBI building, Quang Trung Software City, Tan Chanh Hiep Ward, District 12, Ho Chi Minh City, Vietnam
- Dong Thap University, 783 Pham Huu Lau Street, Ward 6, Cao Lanh City, Dong Thap, Vietnam
- Biomedical Engineering Department, University of Technology -VNU HCM, 268 Ly Thuong Kiet Str., Distr. 10, Ho Chi Minh City, Vietnam
| | - Zuzana Bednarikova
- Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, Kosice 040 01, Slovakia
| | - Miroslav Gancar
- Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, Kosice 040 01, Slovakia
| | - Huynh Quang Linh
- Biomedical Engineering Department, University of Technology -VNU HCM, 268 Ly Thuong Kiet Str., Distr. 10, Ho Chi Minh City, Vietnam
| | - Chin-Kun Hu
- Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan
- Physics Division, National Center for Theretical Sciences, Hsinchu 30013, Taiwan
- Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan
- Department of Systems Science, University of Schanghai for Science and Technology, Shanghai 200093, China
| | - Mai Suan Li
- Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
| | - Zuzana Gazova
- Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, Kosice 040 01, Slovakia
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8
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Manalo RVM. Molecular interactions with redox sites and salt bridges modulate the anti-aggregatory effect of flavonoid, tannin and cardenolide moieties against amyloid-beta (1-42) in silico. In Silico Pharmacol 2017; 5:11. [PMID: 29085768 DOI: 10.1007/s40203-017-0033-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 10/09/2017] [Indexed: 12/14/2022] Open
Abstract
In this study, the interactions of flavonoid, tannin and cardenolide moieties as well as their known metabolites were docked against the apolar NMR structure of the aggregatory amyloid-beta fragment (Aβ1-42). Results showed that the catechin moiety favorably bound Aβ1-42 peptide at Asp23, Asn27, Ser26 and Glu22 residues, with chalcone similarly binding the middle region of the peptide. Remarkably, hippuric and ferulic acids exhibited hydrophobic interactions with Aβ1-42 at the latter portion of the peptide, possibly blocking the salt bridges formed by Glu22-Lys28 which stabilizes Phe19-Gly25, as well as the β-sheet Leu34-Gly38 that are known to exist in peptide aggregation. Meanwhile, the metabolites of hydrolyzable tannins, such as urolithin A and gallic acid, exhibited H-bonding interactions with different residues of Aβ1-42, including Asp1, Asp23 and hydrophobic interactions by gallic acid planar ring to the Hsd6 residue. The coverage was lessened in pyrogallol, suggesting that gallic acid loses its efficacy when further metabolized. Lastly, the different binding poses of the cardenolide moiety interacted with Hsp6 (protonated His) and Tyr10 via hydrophobic interactions. Due to these interactions, the large polycyclic moiety of the ligand would also block further interactions with Hsd6 (prototropic tautomer of His), Asp7, Ser8 and Gly9 that are integral to His6-His13-His14, Arg5-Asp7and Leu34-Gly38 β-sheets, salt bridges in Glu22-Lys28 and turn conformation Phe19-Gly25. Together, these data suggest that the known metabolites of anthocyanins and hydrolyzable tannins contribute the most effective anti-aggregatory interactions with Aβ1-42, with an unexpected role for cardiac glycosides such as the cardenolie moiety. These bring to light the important role of metabolism in vivo, and suggests further investigation on the effects of these metabolites when concentrated in vivo.
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Affiliation(s)
- Rafael Vincent M Manalo
- Department of Biochemistry and Molecular Biology, College of Medicine, University of the Philippines Manila, Ermita, 1000 Manila, Philippines
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9
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Matis I, Delivoria DC, Mavroidi B, Papaevgeniou N, Panoutsou S, Bellou S, Papavasileiou KD, Linardaki ZI, Stavropoulou AV, Vekrellis K, Boukos N, Kolisis FN, Gonos ES, Margarity M, Papadopoulos MG, Efthimiopoulos S, Pelecanou M, Chondrogianni N, Skretas G. An integrated bacterial system for the discovery of chemical rescuers of disease-associated protein misfolding. Nat Biomed Eng 2017; 1:838-852. [DOI: 10.1038/s41551-017-0144-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 09/06/2017] [Indexed: 01/31/2023]
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10
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Inhibition of amyloid oligomerization into different supramolecular architectures by small molecules: mechanistic insights and design rules. Future Med Chem 2017; 9:797-810. [DOI: 10.4155/fmc-2017-0026] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Protein misfolding and aggregation have been associated with several human disorders, including Alzheimer’s, Parkinson’s and Huntington’s diseases, as well as senile systemic amyloidosis and Type II diabetes. However, there is no current disease-modifying therapy available for the treatment of these disorders. In spite of extensive academic, pharmaceutical, medicinal and clinical research, a complete mechanistic model for this family of diseases is still lacking. In this review, we primarily discuss the different types of small molecular entities which have been used for the inhibition of the aggregation process of different amyloidogenic proteins under diseased conditions. These include small peptides, polyphenols, inositols, quinones and their derivatives, and metal chelator molecules. In recent years, these groups of molecules have been extensively studied using in vitro, in vivo and computational models to understand their mechanism of action and common structural features underlying the process of inhibition. A salient feature found to be instrumental in the process of inhibition is the balance between the aromatic unit that functions as the amyloid recognition unit and the hydrophilic amyloid breaker unit. The establishment of structure–function relationship for amyloid-modifying therapies by the various functional entities should serve as an important step toward the development of efficient therapeutics.
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11
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Multi-target-directed therapeutic potential of 7-methoxytacrine-adamantylamine heterodimers in the Alzheimer's disease treatment. Biochim Biophys Acta Mol Basis Dis 2017; 1863:607-619. [DOI: 10.1016/j.bbadis.2016.11.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 11/04/2016] [Accepted: 11/15/2016] [Indexed: 12/30/2022]
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12
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Glasscock C, Lucks J, DeLisa M. Engineered Protein Machines: Emergent Tools for Synthetic Biology. Cell Chem Biol 2016; 23:45-56. [DOI: 10.1016/j.chembiol.2015.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 12/01/2015] [Accepted: 12/01/2015] [Indexed: 11/25/2022]
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13
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Saunders JC, Young LM, Mahood RA, Jackson MP, Revill CH, Foster RJ, Smith DA, Ashcroft AE, Brockwell DJ, Radford SE. An in vivo platform for identifying inhibitors of protein aggregation. Nat Chem Biol 2015; 12:94-101. [PMID: 26656088 PMCID: PMC4720988 DOI: 10.1038/nchembio.1988] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/30/2015] [Indexed: 02/07/2023]
Abstract
Protein aggregation underlies an array of human diseases, yet only one small-molecule therapeutic targeting this process has been successfully developed to date. Here, we introduce an in vivo system, based on a β-lactamase tripartite fusion construct, that is capable of identifying aggregation-prone sequences in the periplasm of Escherichia coli and inhibitors that prevent their aberrant self-assembly. We demonstrate the power of the system using a range of proteins, from small unstructured peptides (islet amyloid polypeptide and amyloid β) to larger, folded immunoglobulin domains. Configured in a 48-well format, the split β-lactamase sensor readily differentiates between aggregation-prone and soluble sequences. Performing the assay in the presence of 109 compounds enabled a rank ordering of inhibition and revealed a new inhibitor of islet amyloid polypeptide aggregation. This platform can be applied to both amyloidogenic and other aggregation-prone systems, independent of sequence or size, and can identify small molecules or other factors able to ameliorate or inhibit protein aggregation.
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Affiliation(s)
- Janet C Saunders
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Lydia M Young
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Rachel A Mahood
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Matthew P Jackson
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Charlotte H Revill
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Chemistry, University of Leeds, LS2 9JT, UK
| | - Richard J Foster
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Chemistry, University of Leeds, LS2 9JT, UK
| | | | - Alison E Ashcroft
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - David J Brockwell
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
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14
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Kumar NS, Nisha N. Phytomedicines as potential inhibitors of β amyloid aggregation: significance to Alzheimer's disease. Chin J Nat Med 2015; 12:801-18. [PMID: 25480511 DOI: 10.1016/s1875-5364(14)60122-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Indexed: 01/13/2023]
Abstract
Throughout the history of drug development, plants have been an important source for the discovery of novel therapeutically active compounds for many diseases. The ethnopharmacological approach has provided several leads to identify potential new drugs from plant sources, including those for memory disorders. For the treatment of Alzheimer's disease the drug discovery focus shifted from cholinesterase inhibitors, to other targets primarily based on two key neuropathological hallmarks, namely the hyperphosphorylation of the tau protein resulting in the formation of neurofibrillary tangles (NFTs), and the increased formation and aggregation of amyloid-beta peptide (Aβ) derived from amyloid precursor protein (APP). The present article aims to provide a comprehensive literature survey of plants and their constituents that have been tested for Aβ aggregation, thus possibly relieving several features of Alzheimer's disease (AD).
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Affiliation(s)
- N Satheesh Kumar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research [NIPER-H], Balanagar, Hyderabad-500037, India.
| | - N Nisha
- Department of Biochemistry, Aurigene Discovery Technologies, Hyderabad-500049, India
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15
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Mira A, Yamashita S, Katakura Y, Shimizu K. In vitro neuroprotective activities of compounds from Angelica shikokiana Makino. Molecules 2015; 20:4813-32. [PMID: 25786165 PMCID: PMC6272295 DOI: 10.3390/molecules20034813] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/03/2015] [Accepted: 03/09/2015] [Indexed: 01/27/2023] Open
Abstract
Angelica shikokiana is widely marketed in Japan as a dietary food supplement. With a focus on neurodegenerative conditions such as Alzheimer's disease, the aerial part was extracted and through bio-guided fractionation, fifteen compounds [α-glutinol, β-amyrin, kaempferol, luteolin, quercetin, kaempferol-3-O-glucoside, kaempferol-3-O-rutinoside, methyl chlorogenate, chlorogenic acid, hyuganin E, 5-(hydroxymethyl)-2-furaldehyde, β-sitosterol-3-O-glucoside, adenosine (isolated for the first time from A. shikokiana), isoepoxypteryxin and isopteryxin] were isolated. Isolated compounds were evaluated for in vitro neuroprotection using acetylcholine esterase inhibitory, protection against hydrogen peroxide and amyloid β peptide (Aβ25-35)-induced neurotoxicity in neuro-2A cells, scavenging of hydroxyl radicals and intracellular reactive oxygen species and thioflavin T assays. Quercetin showed the strongest AChE inhibition (IC50 value = 35.5 µM) through binding to His-440 and Tyr-70 residues at the catalytic and anionic sites of acetylcholine esterase, respectively. Chlorogenic acid, its methyl ester, quercetin and luteolin could significantly protect neuro-2A cells against H2O2-induced neurotoxicity and scavenge hydroxyl radical and intracellular reactive oxygen species. Kaempferol-3-O-rutinoiside, hyuganin E and isoepoxypteryxin significantly decreased Aβ25-35-induced neurotoxicity and Th-T fluorescence. To the best of our knowledge, this is the first report about neuroprotection of hyuganin E and isoepoxypteryxin against Aβ25-35-induced neurotoxicity.
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Affiliation(s)
- Amira Mira
- Division of Systematic Forest and Forest Products Sciences, Department of agroenvironmental sciences, Faculty of Agriculture, Graduate School of Kyushu University, Fukouka 812-8581, Japan.
- Department of Pharmacognosy, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
| | - Shuntaro Yamashita
- Department of Bioscience & Biotechnology, Graduate School of Bioresource and Bioenvironmental sciences, Kyushu University, Fukouka 812-8581, Japan.
| | - Yoshinori Katakura
- Department of Bioscience & Biotechnology, Graduate School of Bioresource and Bioenvironmental sciences, Kyushu University, Fukouka 812-8581, Japan.
| | - Kuniyoshi Shimizu
- Division of Systematic Forest and Forest Products Sciences, Department of agroenvironmental sciences, Faculty of Agriculture, Graduate School of Kyushu University, Fukouka 812-8581, Japan.
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16
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Repalli J, Meruelo D. Screening strategies to identify HSP70 modulators to treat Alzheimer's disease. DRUG DESIGN DEVELOPMENT AND THERAPY 2015; 9:321-31. [PMID: 25609918 PMCID: PMC4294646 DOI: 10.2147/dddt.s72165] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Alzheimer’s disease, the most common type of dementia, is a progressive brain disease that destroys cognitive function and eventually leads to death. In patients with Alzheimer’s disease, beta amyloids and tau proteins form plaques/oligomers and oligomers/tangles that affect the ability of neurons to function properly. Heat shock protein 70 (HSP70) has the ability to prevent aggregation/oligomerization of beta amyloid/tau proteins, making it a potential drug target. To determine this potential, it is essential that we have appropriate in vitro and cell-based assays that help identify specific molecules that affect this aggregation or oligomerization through HSP70. Potential drug candidates could be identified through a series of assays, starting with ATPase assays, followed by aggregation assays with enzymes/proteins and cell-based systems. ATPase assays are effective in identification of ATPase modulators but do not determine the effect of the molecule on beta amyloid and tau proteins. Molecules identified through ATPase assays are validated by thioflavin T aggregation assays in the presence of HSP70. These assays help uncover if a molecule affects beta amyloid and tau through HSP70, but are limited by their in vitro nature. Potential drug candidates are further validated through cell-based assays using mammalian, yeast, or bacterial cultures. However, while these assays are able to determine the effect of a specific molecule on beta amyloid and tau, they fail to determine whether the action is HSP70-dependent. The creation of a novel, direct assay that can demonstrate the antiaggregation effect of a molecule as well as its action through HSP70 would reduce the number of false-positive drug candidates and be more cost-effective and time-effective.
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Affiliation(s)
- Jayanthi Repalli
- Department of Pathology, New York University, Langone Medical Center, New York, NY, USA
| | - Daniel Meruelo
- Department of Pathology, New York University, Langone Medical Center, New York, NY, USA
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Wu H, Zhang F, Williamson N, Jian J, Zhang L, Liang Z, Wang J, An L, Tunnacliffe A, Zheng Y. Effects of secondary metabolite extract from Phomopsis occulta on β-amyloid aggregation. PLoS One 2014; 9:e109438. [PMID: 25275648 PMCID: PMC4183696 DOI: 10.1371/journal.pone.0109438] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 09/02/2014] [Indexed: 11/19/2022] Open
Abstract
Inhibition of β-amyloid (Aβ) aggregation is an attractive therapeutic and preventive strategy for the discovery of disease-modifying agents in Alzheimer's disease (AD). Phomopsis occulta is a new, salt-tolerant fungus isolated from mangrove Pongamia pinnata (L.) Pierre. We report here the inhibitory effects of secondary metabolites from Ph. occulta on the aggregation of Aβ42. It was found that mycelia extracts (MEs) from Ph. occulta cultured with 0, 2, and 3 M NaCl exhibited inhibitory activity in an E. coli model of Aβ aggregation. A water-soluble fraction, ME0-W-F1, composed of mainly small peptides, was able to reduce aggregation of an Aβ42-EGFP fusion protein and an early onset familial mutation Aβ42E22G-mCherry fusion protein in transfected HEK293 cells. ME0-W-F1 also antagonized the cytotoxicity of Aβ42 in the neural cell line SH-SY5Y in dose-dependent manner. Moreover, SDS-PAGE and FT-IR analysis confirmed an inhibitory effect of ME0-W-F1 on the aggregation of Aβ42 in vitro. ME0-W-F1 blocked the conformational transition of Aβ42 from α-helix/random coil to β-sheet, and thereby inhibited formation of Aβ42 tetramers and high molecular weight oligomers. ME0-W-F1 and other water-soluble secondary metabolites from Ph. occulta therefore represent new candidate natural products against aggregation of Aβ42, and illustrate the potential of salt tolerant fungi from mangrove as resources for the treatment of AD and other diseases.
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Affiliation(s)
- Haiqiang Wu
- College of Life Sciences, Shenzhen University, Shenzhen, China
| | - Fang Zhang
- College of Life Sciences, Shenzhen University, Shenzhen, China
| | - Neil Williamson
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
| | - Jie Jian
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
- College of Pharmacy, Guilin Medical University, Guilin, China
| | - Liao Zhang
- College of Life Sciences, Shenzhen University, Shenzhen, China
| | - Zeqiu Liang
- College of Life Sciences, Shenzhen University, Shenzhen, China
| | - Jinyu Wang
- College of Life Sciences, Shenzhen University, Shenzhen, China
| | - Linkun An
- School of Pharmaceutical Science, Sun Yat-sen University, Guangzhou, China
| | - Alan Tunnacliffe
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (AT); (YZ)
| | - Yizhi Zheng
- College of Life Sciences, Shenzhen University, Shenzhen, China
- * E-mail: (AT); (YZ)
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18
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Waraho-Zhmayev D, Meksiriporn B, Portnoff AD, DeLisa MP. Optimizing recombinant antibodies for intracellular function using hitchhiker-mediated survival selection. Protein Eng Des Sel 2014; 27:351-8. [PMID: 25225416 DOI: 10.1093/protein/gzu038] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The 'hitchhiker' mechanism of the bacterial twin-arginine translocation pathway has previously been adapted as a genetic selection for detecting pairwise protein interactions in the cytoplasm of living Escherichia coli cells. Here, we extended this method, called FLI-TRAP, for rapid isolation of intracellular antibodies (intrabodies) in the single-chain Fv format that possess superior traits simply by demanding bacterial growth on high concentrations of antibiotic. Following just a single round of survival-based enrichment using FLI-TRAP, variants of an intrabody against the dimerization domain of the yeast Gcn4p transcription factor were isolated having significantly greater intracellular stability that translated to yield enhancements of >10-fold. Likewise, an intrabody specific for the non-amyloid component region of α-synuclein was isolated that has ~8-fold improved antigen-binding affinity. Collectively, our results illustrate the potential of the FLI-TRAP method for intracellular stabilization and affinity maturation of intrabodies, all without the need for purification or immobilization of the antigen.
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Affiliation(s)
- Dujduan Waraho-Zhmayev
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA Biological Engineering Program, Faculty of Engineering, King Mongkut's University of Technology Thonburi, 126 Pracha-utid Road, Bangmod, Toongkru, Bangkok 10140, Thailand
| | | | - Alyse D Portnoff
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Matthew P DeLisa
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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19
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Lee J, Jung DW, Kim WH, Um JI, Yim SH, Oh WK, Williams DR. Development of a highly visual, simple, and rapid test for the discovery of novel insulin mimetics in living vertebrates. ACS Chem Biol 2013; 8:1803-14. [PMID: 23725454 DOI: 10.1021/cb4000162] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Diabetes mellitus is a global epidemic with major impacts on human health and society. Drug discovery for diabetes can be facilitated by the development of a rapid, vertebrate-based screen for identifying new insulin mimetic compounds. Our study describes the first development of a zebrafish-based system based on direct monitoring of glucose flux and validated for identifying novel anti-diabetic drugs. Our system utilizes a fluorescent-tagged glucose probe in an experimentally convenient 96-well plate format. To validate our new system, we identified compounds that can induce glucose uptake via activity-guided fractionation of the inner shell from the Japanese Chestnut (Castanea crenata). The best performing compound, UP3.2, was identified as fraxidin and validated as a novel insulin mimetic using a mammalian adipocyte system. Additional screening using sets of saponin- and triazine-based compounds was undertaken to further validate this assay, which led to the discovery of triazine PP-II-A03 as a novel insulin mimetic. Moreover, we demonstrate that our zebrafish-based system allows concomitant toxicological analysis of anti-diabetic drug candidates. Thus, we have developed a rapid and inexpensive vertebrate model that can enhance diabetes drug discovery by preselecting hits from chemical library screens, before testing in relatively expensive rodent assays.
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Affiliation(s)
| | | | | | | | | | - Won Keun Oh
- Korea Bioactive Natural Material
Bank, College of Pharmacy, Seoul National University, Seoul 151-742, Republic of Korea
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20
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Abstract
Here we describe a protocol for the generation of amyloid aggregates of target amyloidogenic proteins using a bacteria-based system called curli-dependent amyloid generator (C-DAG). C-DAG relies on the natural ability of Escherichia coli cells to elaborate surface-associated amyloid fibers known as curli. An N-terminal signal sequence directs the secretion of the major curli subunit CsgA. The transfer of this signal sequence to the N terminus of heterologous amyloidogenic proteins similarly directs their export to the cell surface, where they assemble as amyloid fibrils. Notably, protein secretion through the curli export pathway facilitates acquisition of the amyloid fold specifically for proteins that have an inherent amyloid-forming propensity. Thus, C-DAG provides a cell-based alternative to widely used in vitro assays for studying amyloid aggregation, and it circumvents the need for protein purification. In particular, C-DAG provides a simple method for identifying amyloidogenic proteins and for distinguishing between amyloidogenic and non-amyloidogenic variants of a particular protein. Once the appropriate vectors have been constructed, results can be obtained within 1 week.
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Affiliation(s)
- Viknesh Sivanathan
- Department of Microbiology and Immunobiology, Harvard Medical School, 4 Blackfan Circle, Boston, MA 02115
| | - Ann Hochschild
- Department of Microbiology and Immunobiology, Harvard Medical School, 4 Blackfan Circle, Boston, MA 02115
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21
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Wang Q, Yu X, Patal K, Hu R, Chuang S, Zhang G, Zheng J. Tanshinones inhibit amyloid aggregation by amyloid-β peptide, disaggregate amyloid fibrils, and protect cultured cells. ACS Chem Neurosci 2013; 4:1004-15. [PMID: 23506133 PMCID: PMC3756451 DOI: 10.1021/cn400051e] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 03/18/2013] [Indexed: 01/10/2023] Open
Abstract
The misfolding and aggregation of amyloid-β (Aβ) peptides into amyloid fibrils is regarded as one of the causative events in the pathogenesis of Alzheimer's disease (AD). Tanshinones extracted from Chinese herb Danshen (Salvia Miltiorrhiza Bunge) were traditionally used as anti-inflammation and cerebrovascular drugs due to their antioxidation and antiacetylcholinesterase effects. A number of studies have suggested that tanshinones could protect neuronal cells. In this work, we examine the inhibitory activity of tanshinone I (TS1) and tanshinone IIA (TS2), the two major components in the Danshen herb, on the aggregation and toxicity of Aβ1-42 using atomic force microscopy (AFM), thioflavin-T (ThT) fluorescence assay, cell viability assay, and molecular dynamics (MD) simulations. AFM and ThT results show that both TS1 and TS2 exhibit different inhibitory abilities to prevent unseeded amyloid fibril formation and to disaggregate preformed amyloid fibrils, in which TS1 shows better inhibitory potency than TS2. Live/dead assay further confirms that introduction of a very small amount of tanshinones enables protection of cultured SH-SY5Y cells against Aβ-induced cell toxicity. Comparative MD simulation results reveal a general tanshinone binding mode to prevent Aβ peptide association, showing that both TS1 and TS2 preferentially bind to a hydrophobic β-sheet groove formed by the C-terminal residues of I31-M35 and M35-V39 and several aromatic residues. Meanwhile, the differences in binding distribution, residues, sites, population, and affinity between TS1-Aβ and TS2-Aβ systems also interpret different inhibitory effects on Aβ aggregation as observed by in vitro experiments. More importantly, due to nonspecific binding mode of tanshinones, it is expected that tanshinones would have a general inhibitory efficacy of a wide range of amyloid peptides. These findings suggest that tanshinones, particularly TS1 compound, offer promising lead compounds with dual protective role in anti-inflammation and antiaggregation for further development of Aβ inhibitors to prevent and disaggregate amyloid formation.
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Affiliation(s)
- Qiuming Wang
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
| | - Xiang Yu
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
| | - Kunal Patal
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
| | - Rundong Hu
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
| | - Steven Chuang
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
| | - Ge Zhang
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
| | - Jie Zheng
- Department of Chemical and Biomolecular Engineering, Department of Biomedical
Engineering, and College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio
44325, United States
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22
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Jung DW, Kim WH, Park SH, Lee J, Kim J, Su D, Ha HH, Chang YT, Williams DR. A unique small molecule inhibitor of enolase clarifies its role in fundamental biological processes. ACS Chem Biol 2013; 8:1271-82. [PMID: 23547795 DOI: 10.1021/cb300687k] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Enolase is a component of the glycolysis pathway and a "moonlighting" protein, with important roles in diverse cellular processes that are not related to its function in glycolysis. However, small molecule tools to probe enolase function have been restricted to crystallography or enzymology. In this study, we report the discovery of the small molecule "ENOblock", which is the first, nonsubstrate analogue that directly binds to enolase and inhibits its activity. ENOblock was isolated by small molecule screening in a cancer cell assay to detect cytotoxic agents that function in hypoxic conditions, which has previously been shown to induce drug resistance. Further analysis revealed that ENOblock can inhibit cancer cell metastasis in vivo. Moreover, an unexpected role for enolase in glucose homeostasis was revealed by in vivo analysis. Thus, ENOblock is the first reported enolase inhibitor that is suitable for biological assays. This new chemical tool may also be suitable for further study as a cancer and diabetes drug candidate.
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Affiliation(s)
- Da-Woon Jung
- New Drug Targets Laboratory,
School of Life Sciences, Gwangju Institute of Science and Technology, 1 Oryong-Dong, Buk-Gu, Gwangju 500-712,
Republic of Korea
| | - Woong-Hee Kim
- New Drug Targets Laboratory,
School of Life Sciences, Gwangju Institute of Science and Technology, 1 Oryong-Dong, Buk-Gu, Gwangju 500-712,
Republic of Korea
| | - Si-Hwan Park
- New Drug Targets Laboratory,
School of Life Sciences, Gwangju Institute of Science and Technology, 1 Oryong-Dong, Buk-Gu, Gwangju 500-712,
Republic of Korea
| | - Jinho Lee
- New Drug Targets Laboratory,
School of Life Sciences, Gwangju Institute of Science and Technology, 1 Oryong-Dong, Buk-Gu, Gwangju 500-712,
Republic of Korea
| | - Jinmi Kim
- New Drug Targets Laboratory,
School of Life Sciences, Gwangju Institute of Science and Technology, 1 Oryong-Dong, Buk-Gu, Gwangju 500-712,
Republic of Korea
| | - Dongdong Su
- Department
of Chemistry, National University
of Singapore and MedChem Program of Life Sciences Institute, National University of Singapore, 3 Science Drive 3,
Singapore 117543
| | - Hyung-Ho Ha
- College
of Pharmacy, Sunchon National University, Sunchon, 570-742, Korea
| | - Young-Tae Chang
- Department
of Chemistry, National University
of Singapore and MedChem Program of Life Sciences Institute, National University of Singapore, 3 Science Drive 3,
Singapore 117543
- Laboratory
of Bioimaging Probe
Development, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR), Singapore
138667
| | - Darren R. Williams
- New Drug Targets Laboratory,
School of Life Sciences, Gwangju Institute of Science and Technology, 1 Oryong-Dong, Buk-Gu, Gwangju 500-712,
Republic of Korea
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23
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Waraho-Zhmayev D, Gkogka L, Yu TY, DeLisa MP. A microbial sensor for discovering structural probes of protein misfolding and aggregation. Prion 2013; 7:151-6. [PMID: 23357829 DOI: 10.4161/pri.23328] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In all cell types, protein homeostasis, or "proteostasis," is maintained by sophisticated quality control networks that regulate protein synthesis, folding, trafficking, aggregation, disaggregation, and degradation. In one notable example, Escherichia coli employ a proteostasis system that determines whether substrates of the twin-arginine translocation (Tat) pathway are correctly folded and thus suitable for transport across the tightly sealed cytoplasmic membrane. Herein, we review growing evidence that the Tat translocase itself discriminates folded proteins from those that are misfolded and/or aggregated, preferentially exporting only the former. Genetic suppressors that inactivate this mechanism have recently been isolated and provide direct evidence for the participation of the Tat translocase in structural proofreading of its protein substrates. We also discuss how this discriminatory "folding sensor" has been exploited for the discovery of structural probes (e.g., sequence mutations, pharmacologic chaperones, intracellular antibodies) that modulate the folding and solubility of virtually any protein-of-interest, including those associated with aggregation diseases (e.g., α-synuclein, amyloid-β protein). Taken together, these studies highlight the utility of engineered bacteria for rapidly and inexpensively uncovering potent anti-aggregation factors.
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24
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Wright O, Zhang L, Liu Y, Yoshimi T, Zheng Y, Tunnacliffe A. Critique of the use of fluorescence-based reporters in Escherichia coli
as a screening tool for the identification of peptide inhibitors of Aβ42 aggregation. J Pept Sci 2012; 19:74-83. [DOI: 10.1002/psc.2474] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 10/11/2012] [Accepted: 11/06/2012] [Indexed: 11/09/2022]
Affiliation(s)
- Oliver Wright
- Department of Chemical Engineering and Biotechnology; University of Cambridge; New Museums Site, Pembroke Street Cambridge CB2 3RA UK
| | - Liao Zhang
- Shenzhen Key Laboratory of Microbiology and Gene Engineering; College of Life Sciences; Nanhai Ave 3688 Shenzhen City Guangdong Province China 518060
| | - Yun Liu
- Shenzhen Key Laboratory of Microbiology and Gene Engineering; College of Life Sciences; Nanhai Ave 3688 Shenzhen City Guangdong Province China 518060
| | - Tatsuya Yoshimi
- National Center for Geriatrics and Gerontology; 35 Gengo, Morioka-machi Obu City Aichi 474-8511 Japan
| | - Yizhi Zheng
- Shenzhen Key Laboratory of Microbiology and Gene Engineering; College of Life Sciences; Nanhai Ave 3688 Shenzhen City Guangdong Province China 518060
| | - Alan Tunnacliffe
- Department of Chemical Engineering and Biotechnology; University of Cambridge; New Museums Site, Pembroke Street Cambridge CB2 3RA UK
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25
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Speck J, Räuber C, Kükenshöner T, Niemöller C, Mueller KJ, Schleberger P, Dondapati P, Hecky J, Arndt KM, Müller KM. TAT hitchhiker selection expanded to folding helpers, multimeric interactions and combinations with protein fragment complementation. Protein Eng Des Sel 2012; 26:225-42. [PMID: 23223941 DOI: 10.1093/protein/gzs098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Janina Speck
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
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26
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Sivanathan V, Hochschild A. Generating extracellular amyloid aggregates using E. coli cells. Genes Dev 2012; 26:2659-67. [PMID: 23166018 DOI: 10.1101/gad.205310.112] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Diverse proteins are known to be capable of forming amyloid aggregates, self-seeding fibrillar assemblies that may be biologically functional or pathological. Well-known examples include neurodegenerative disease-associated proteins that misfold as amyloid, fungal prion proteins that can transition to a self-propagating amyloid form and certain bacterial proteins that fold as amyloid at the cell surface and promote biofilm formation. To further explore the diversity of amyloidogenic proteins, generally applicable methods for identifying them are critical. Here we describe a cell-based method for generating amyloid aggregates that relies on the natural ability of Escherichia coli cells to elaborate amyloid fibrils at the cell surface. We use several different yeast prion proteins and the human huntingtin protein to show that protein secretion via this specialized export pathway promotes acquisition of the amyloid fold specifically for proteins that have an inherent amyloid-forming propensity. Furthermore, our findings establish the potential of this E. coli-based system to facilitate the implementation of high-throughput screens for identifying amyloidogenic proteins and modulators of amyloid aggregation.
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Affiliation(s)
- Viknesh Sivanathan
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115 USA
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27
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Zhao T, Zeng Y, Kermode AR. A plant cell-based system that predicts aβ42 misfolding: potential as a drug discovery tool for Alzheimer's disease. Mol Genet Metab 2012; 107:571-9. [PMID: 22944366 DOI: 10.1016/j.ymgme.2012.08.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 08/09/2012] [Accepted: 08/09/2012] [Indexed: 01/02/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid β (Aβ) peptides and the failure of mechanisms to clear toxic aggregates. The Aβ42 peptide is considered to be a causative factor that underlies the pathophysiology of AD, in part due to its propensity for misfolding and aggregation; the small oligomers that result represent toxic species. Thus agents that prevent Aβ42 misfolding/aggregation or, alternatively improve Aβ42 oligomer clearance, may have significant therapeutic value. We have developed the basis for a drug screening system based on transgenic plant cells that express Aβ42 fusion proteins to serve as the reliable indicators of the general conformational status of Aβ42. Within cells of transgenic tobacco and Nicotiana benthamiana, misfolding of Aβ42 causes the misfolding of a GFP fusion partner, and consequently there is a loss of fluorescence associated with the native GFP protein. In a similar fusion consisting of Aβ42 linked to hygromycin phosphotransferase II (Hpt II), a hygromycin-resistance marker, misfolding of Aβ42 leads to a misfolded Hpt II, and consequently the transgenic cells are unable to grow on media containing hygromycin. Importantly, substitution of the 'aggregation-prone' Aβ42 with a missense mutant of Aβ42 (F19S/L34F) that is not prone to misfolding/aggregation, 'rescues' both fusion partners. Several 'positive control' chemicals that represent inhibitors of Aβ42 aggregation, including curcumin, epigallocatechin-3-gallate (EGCG), and resveratrol show efficacy in preventing the Aβ42-fusion proteins from misfolding/aggregating in the transgenic plant cells. We discuss the potential of the two fusion protein systems to serve as the basis for an inexpensive, selective, and efficient screening system in which a plant cell can fluoresce or survive only in the presence of drug candidates that are able to prevent Aβ42 misfolding/aggregation.
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Affiliation(s)
- Tiehan Zhao
- Department of Biological Sciences, Simon Fraser University, 8888 University Dr, Burnaby, BC, Canada V5A 1S6.
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28
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Villar-Piqué A, Espargaró A, Sabaté R, de Groot NS, Ventura S. Using bacterial inclusion bodies to screen for amyloid aggregation inhibitors. Microb Cell Fact 2012; 11:55. [PMID: 22553999 PMCID: PMC3495732 DOI: 10.1186/1475-2859-11-55] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Accepted: 05/03/2012] [Indexed: 12/28/2022] Open
Abstract
Background The amyloid-β peptide (Aβ42) is the main component of the inter-neuronal amyloid plaques characteristic of Alzheimer's disease (AD). The mechanism by which Aβ42 and other amyloid peptides assemble into insoluble neurotoxic deposits is still not completely understood and multiple factors have been reported to trigger their formation. In particular, the presence of endogenous metal ions has been linked to the pathogenesis of AD and other neurodegenerative disorders. Results Here we describe a rapid and high-throughput screening method to identify molecules able to modulate amyloid aggregation. The approach exploits the inclusion bodies (IBs) formed by Aβ42 when expressed in bacteria. We have shown previously that these aggregates retain amyloid structural and functional properties. In the present work, we demonstrate that their in vitro refolding is selectively sensitive to the presence of aggregation-promoting metal ions, allowing the detection of inhibitors of metal-promoted amyloid aggregation with potential therapeutic interest. Conclusions Because IBs can be produced at high levels and easily purified, the method overcomes one of the main limitations in screens to detect amyloid modulators: the use of expensive and usually highly insoluble synthetic peptides.
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Affiliation(s)
- Anna Villar-Piqué
- Departament de Bioquímica i Biologia Molecular, Facultat de Biociències, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Spain
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29
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Macromolecular and small-molecule modulation of intracellular Aβ42 aggregation and associated toxicity. Biochem J 2012; 442:507-15. [DOI: 10.1042/bj20111661] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Aβ (amyloid β-peptide) has a central role in AD (Alzheimer's disease) where neuronal toxicity is linked to its extracellular and intracellular accumulation as oligomeric species. Searching for molecules that attenuate Aβ aggregation could uncover novel therapies for AD, but most studies in mammalian cells have inferred aggregation indirectly by assessing levels of secreted Aβ peptide. In the present study we establish a mammalian cell system for the direct visualization of Aβ formation by expression of an Aβ42–EGFP (enhanced green fluorescent protein) fusion protein in the human embryonic kidney cell line T-REx293, and use this to identify both macromolecules and small molecules that reduce aggregation and associated cell toxicity. Thus a molecular shield protein AavLEA1 [Aphelenchus avenae LEA (late embryogenesis abundant) protein 1], which limits aggregation of proteins with expanded poly(Q) repeats, is also effective against Aβ42–EGFP when co-expressed in T-REx293 cells. A screen of polysaccharide and small organic molecules from medicinal plants and fungi reveals one candidate in each category, PS5 (polysaccharide 5) and ganoderic acid DM respectively, with activity against Aβ. Both PS5 and ganoderic acid DM probably promote Aβ aggregate clearance indirectly through the proteasome. The model is therefore of value to study the effects of intracellular Aβ on cell physiology and to identify reagents that counteract those effects.
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30
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Waraho D, DeLisa MP. Identifying and optimizing intracellular protein-protein interactions using bacterial genetic selection. Methods Mol Biol 2012; 813:125-143. [PMID: 22083739 DOI: 10.1007/978-1-61779-412-4_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Protein-protein interactions are crucial for the vast majority of biological processes. To fully understand these processes therefore requires methods for identifying protein interactions within the complex cellular environment. To isolate interacting proteins, we have developed a simple and reliable genetic selection by exploiting the inbuilt "hitchhiker" mechanism of the Escherichia coli twin-arginine translocation (Tat) pathway. This method is based on the unique ability of the Tat system to efficiently co-localize noncovalent complexes of two folded polypeptides to the periplasmic space of E. coli. The genetic selection is comprised of two engineered fusion proteins: an N-terminal Tat signal peptide fused to the protein of interest, and the known or putative partner protein fused to mature TEM-1 β-lactamase. The efficiency with which co-localized β-lactamase chimeras are exported in the periplasm, and thus confer ampicillin resistance to cells, is directly linked to the relative binding affinity of the protein-ligand system. Thus, ampicillin resistance can be used as a convenient readout for identifying and optimizing protein interactions in E. coli. Furthermore, because Tat substrates must be correctly folded for export, our method favors the identification of soluble, non-aggregating, protease-resistant protein pairs. Overall, we anticipate that this new selection tool will be useful for discovering and engineering protein drugs, protein complexes for structural biology, factors that inhibit PPIs, and components for synthetic biology.
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Affiliation(s)
- Dujduan Waraho
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, USA
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Naik S, Zhang N, Gao P, Fisher MT. On the design of broad based screening assays to identify potential pharmacological chaperones of protein misfolding diseases. Curr Top Med Chem 2012; 12:2504-22. [PMID: 23339304 PMCID: PMC3751797 DOI: 10.2174/1568026611212220006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/18/2012] [Accepted: 09/21/2012] [Indexed: 01/11/2023]
Abstract
Correcting aberrant folds that develop during protein folding disease states is now an active research endeavor that is attracting increasing attention from both academic and industrial circles. One particular approach focuses on developing or identifying small molecule correctors or pharmacological chaperones that specifically stabilize the native fold. Unfortunately, the limited screening platforms available to rapidly identify or validate potential drug candidates are usually inadequate or slow because the folding disease proteins in question are often transiently folded and/or aggregation-prone, complicating and/or interfering with the assay outcomes. In this review, we outline and discuss the numerous platform options currently being employed to identify small molecule therapeutics for folding diseases. Finally, we describe a new stability screening approach that is broad based and is easily applicable toward a very large number of both common and rare protein folding diseases. The label free screening method described herein couples the promiscuity of the GroEL binding to transient aggregation-prone hydrophobic folds with surface plasmon resonance enabling one to rapidly identify potential small molecule pharmacological chaperones.
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Affiliation(s)
- Subhashchandra Naik
- University of Kansas Medical Center, Department of Biochemistry, Kansas City KS, USA
| | - Na Zhang
- University of Kansas, Protein Production Facility, Lawrence KS, USA
| | - Phillip Gao
- University of Kansas, Protein Production Facility, Lawrence KS, USA
| | - Mark T. Fisher
- University of Kansas Medical Center, Department of Biochemistry, Kansas City KS, USA
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Mohamed T, Yeung JC, Rao PP. Development of 2-substituted-N-(naphth-1-ylmethyl) and N-benzhydrylpyrimidin-4-amines as dual cholinesterase and Aβ-aggregation inhibitors: Synthesis and biological evaluation. Bioorg Med Chem Lett 2011; 21:5881-7. [DOI: 10.1016/j.bmcl.2011.07.091] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 07/22/2011] [Accepted: 07/25/2011] [Indexed: 01/14/2023]
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Park SK, Pegan SD, Mesecar AD, Jungbauer LM, LaDu MJ, Liebman SW. Development and validation of a yeast high-throughput screen for inhibitors of Aβ₄₂ oligomerization. Dis Model Mech 2011; 4:822-31. [PMID: 21810907 PMCID: PMC3209651 DOI: 10.1242/dmm.007963] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Recent reports point to small soluble oligomers, rather than insoluble fibrils, of amyloid β (Aβ), as the primary toxic species in Alzheimer’s disease. Previously, we developed a low-throughput assay in yeast that is capable of detecting small Aβ42 oligomer formation. Specifically, Aβ42 fused to the functional release factor domain of yeast translational termination factor, Sup35p, formed sodium dodecyl sulfate (SDS)-stable low-n oligomers in living yeast, which impaired release factor activity. As a result, the assay for oligomer formation uses yeast growth to indicate restored release factor activity and presumably reduced oligomer formation. We now describe our translation of this assay into a high-throughput screen (HTS) for anti-oligomeric compounds. By doing so, we also identified two presumptive anti-oligomeric compounds from a sub-library of 12,800 drug-like small molecules. Subsequent biochemical analysis confirmed their anti-oligomeric activity, suggesting that this form of HTS is an efficient, sensitive and cost-effective approach to identify new inhibitors of Aβ42 oligomerization.
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Affiliation(s)
- Sei-Kyoung Park
- Laboratory for Molecular Biology, Department of Biological Sciences, University of Illinois, Chicago, IL 60607, USA
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Mohamed T, Zhao X, Habib LK, Yang J, Rao PPN. Design, synthesis and structure-activity relationship (SAR) studies of 2,4-disubstituted pyrimidine derivatives: dual activity as cholinesterase and Aβ-aggregation inhibitors. Bioorg Med Chem 2011; 19:2269-81. [PMID: 21429752 PMCID: PMC3066269 DOI: 10.1016/j.bmc.2011.02.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 02/11/2011] [Accepted: 02/16/2011] [Indexed: 01/14/2023]
Abstract
A novel class of 2,4-disubstituted pyrimidines (7a-u, 8a-f, 9a-e) that possess substituents with varying steric and electronic properties at the C-2 and C-4 positions, were designed, synthesized and evaluated as dual cholinesterase and amyloid-β (Aβ)-aggregation inhibitors. In vitro screening identified N-(naphth-1-ylmethyl)-2-(pyrrolidin-1-yl)pyrimidin-4-amine (9a) as the most potent AChE inhibitor (IC(50)=5.5 μM). Among this class of compounds, 2-(4-methylpiperidin-1-yl)-N-(naphth-1-ylmethyl)pyrimidin-4-amine (9e) was identified as the most potent and selective BuChE inhibitor (IC(50)=2.2 μM, selectivity index=11.7) and was about 5.7-fold more potent compared to the commercial, approved reference drug galanthamine (BuChE IC(50)=12.6 μM). In addition, the selective AChE inhibitor N-benzyl-2-(4-methylpiperazin-1-yl)pyrimidin-4-amine (7d), exhibited good inhibition of hAChE-induced aggregation of Aβ(1-40) fibrils (59% inhibition). Furthermore, molecular modeling studies indicate that a central pyrimidine ring serves as a suitable template to develop dual inhibitors of cholinesterase and AChE-induced Aβ aggregation thereby targeting multiple pathological routes in AD.
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Affiliation(s)
- Tarek Mohamed
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
- School of Pharmacy, Health Sciences Campus, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Xiaobei Zhao
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California, U.S.A 92093-0358
| | - Lila K. Habib
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, California, U.S.A 92093-0358
| | - Jerry Yang
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California, U.S.A 92093-0358
| | - Praveen P. N. Rao
- School of Pharmacy, Health Sciences Campus, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
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Quan S, Koldewey P, Tapley T, Kirsch N, Ruane KM, Pfizenmaier J, Shi R, Hofmann S, Foit L, Ren G, Jakob U, Xu Z, Cygler M, Bardwell JCA. Genetic selection designed to stabilize proteins uncovers a chaperone called Spy. Nat Struct Mol Biol 2011; 18:262-9. [PMID: 21317898 PMCID: PMC3079333 DOI: 10.1038/nsmb.2016] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 12/15/2010] [Indexed: 12/20/2022]
Abstract
To optimize the in vivo folding of proteins, we linked protein stability to antibiotic resistance, thereby forcing bacteria to effectively fold and stabilize proteins. When we challenged Escherichia coli to stabilize a very unstable periplasmic protein, it massively overproduced a periplasmic protein called Spy, which increases the steady-state levels of a set of unstable protein mutants up to 700-fold. In vitro studies demonstrate that the Spy protein is an effective ATP-independent chaperone that suppresses protein aggregation and aids protein refolding. Our strategy opens up new routes for chaperone discovery and the custom tailoring of the in vivo folding environment. Spy forms thin, apparently flexible cradle-shaped dimers. Spy is unlike the structure of any previously solved chaperone, making it the prototypical member of a new class of small chaperones that facilitate protein refolding in the absence of energy cofactors.
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Affiliation(s)
- Shu Quan
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
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Lim HK, Mansell TJ, Linderman SW, Fisher AC, Dyson MR, DeLisa MP. Mining mammalian genomes for folding competent proteins using Tat-dependent genetic selection in Escherichia coli. Protein Sci 2010; 18:2537-49. [PMID: 19830686 DOI: 10.1002/pro.262] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Recombinant expression of eukaryotic proteins in Escherichia coli is often limited by poor folding and solubility. To address this problem, we employed a recently developed genetic selection for protein folding and solubility based on the bacterial twin-arginine translocation (Tat) pathway to rapidly identify properly folded recombinant proteins or soluble protein domains of mammalian origin. The coding sequences for 29 different mammalian polypeptides were cloned as sandwich fusions between an N-terminal Tat export signal and a C-terminal selectable marker, namely beta-lactamase. Hence, expression of the selectable marker and survival on selective media was linked to Tat export of the target mammalian protein. Since the folding quality control feature of the Tat pathway prevents export of misfolded proteins, only correctly folded fusion proteins reached the periplasm and conferred cell survival. In general, the ability to confer growth was found to relate closely to the solubility profile and molecular weight of the protein, although other features such as number of contiguous hydrophobic amino acids and cysteine content may also be important. These results highlight the capacity of Tat selection to reveal the folding potential of mammalian proteins and protein domains without the need for structural or functional information about the target protein.
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Affiliation(s)
- Hyung-Kwon Lim
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA
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Tulip P, Bates S. First principles determination of structural, electronic and lattice dynamical properties of a model dipeptide molecular crystal. Mol Phys 2009. [DOI: 10.1080/00268970903224955] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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