451
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Yang XX, Chang RM, Yue Y, Li XN. Cardiac Muscle/Cell Membrane Chromatography-Offline-Liquid Chromatography/Mass Spectrometry Method to Identify Bioactive Components from Traditional Chinese Medicines. ANAL LETT 2013. [DOI: 10.1080/00032719.2012.762585] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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452
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Makley LN, Gestwicki JE. Expanding the number of 'druggable' targets: non-enzymes and protein-protein interactions. Chem Biol Drug Des 2013; 81:22-32. [PMID: 23253128 DOI: 10.1111/cbdd.12066] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Following sequencing and assembly of the human genome, the preferred methods for identification of new drug targets have changed dramatically. Modern tactics such as genome-wide association studies (GWAS) and deep sequencing are fundamentally different from the pharmacology-guided approaches used previously, in which knowledge of small molecule ligands acting at their cellular targets was the primary discovery engine. A consequence of the 'target-first, pharmacology-second' strategy is that many predicted drug targets are non-enzymes, such as scaffolding, regulatory or structural proteins, and their activities are often dependent on protein-protein interactions (PPIs). These types of targets create unique challenges to drug discovery efforts because enzymatic turnover cannot be used as a convenient surrogate for compound potency. Moreover, it is often challenging to predict how ligand binding to non-enzymes might affect changes in protein function and/or pathobiology. Thus, in the postgenomic era, targets might be strongly implicated by molecular biology-based methods, yet they often later earn the designation of 'undruggable'. Can the scope of available targets be widened to include these promising, but challenging, non-enzymes? In this review, we discuss advances in high-throughput screening (HTS) technology and chemical library design that are emerging to deal with these challenges.
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Affiliation(s)
- Leah N Makley
- Departments of Pathology, Biological Chemistry and the Interdisciplinary Program in Medicinal Chemistry, The Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109-2216, USA
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453
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Serba C, Winssinger N. Following the Lead from Nature: Divergent Pathways in Natural Product Synthesis and Diversity-Oriented Synthesis. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300201] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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454
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Gu J, Gui Y, Chen L, Yuan G, Lu HZ, Xu X. Use of natural products as chemical library for drug discovery and network pharmacology. PLoS One 2013; 8:e62839. [PMID: 23638153 PMCID: PMC3636197 DOI: 10.1371/journal.pone.0062839] [Citation(s) in RCA: 234] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 03/28/2013] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Natural products have been an important source of lead compounds for drug discovery. How to find and evaluate bioactive natural products is critical to the achievement of drug/lead discovery from natural products. METHODOLOGY We collected 19,7201 natural products structures, reported biological activities and virtual screening results. Principal component analysis was employed to explore the chemical space, and we found that there was a large portion of overlap between natural products and FDA-approved drugs in the chemical space, which indicated that natural products had large quantity of potential lead compounds. We also explored the network properties of natural product-target networks and found that polypharmacology was greatly enriched to those compounds with large degree and high betweenness centrality. In order to make up for a lack of experimental data, high throughput virtual screening was employed. All natural products were docked to 332 target proteins of FDA-approved drugs. The most potential natural products for drug discovery and their indications were predicted based on a docking score-weighted prediction model. CONCLUSIONS Analysis of molecular descriptors, distribution in chemical space and biological activities of natural products was conducted in this article. Natural products have vast chemical diversity, good drug-like properties and can interact with multiple cellular target proteins.
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Affiliation(s)
- Jiangyong Gu
- Beijing National Laboratory for Molecular Sciences, State Key Lab of Rare Earth Material Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China
| | - Yuanshen Gui
- Beijing National Laboratory for Molecular Sciences, State Key Lab of Rare Earth Material Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China
- Institute of Science and Technology, China Agricultural University, Beijing, P. R. China
| | - Lirong Chen
- Beijing National Laboratory for Molecular Sciences, State Key Lab of Rare Earth Material Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China
| | - Gu Yuan
- Beijing National Laboratory for Molecular Sciences, State Key Lab of Rare Earth Material Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China
| | - Hui-Zhe Lu
- Beijing National Laboratory for Molecular Sciences, State Key Lab of Rare Earth Material Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China
- Institute of Science and Technology, China Agricultural University, Beijing, P. R. China
| | - Xiaojie Xu
- Beijing National Laboratory for Molecular Sciences, State Key Lab of Rare Earth Material Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China
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455
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Li X, Yang X, Liu Y, Gong N, Yao W, Chen P, Qin J, Jin H, Li J, Chu R, Shan L, Zhang R, Zhang W, Wang H. Japonicone A Suppresses Growth of Burkitt Lymphoma Cells through Its Effect on NF-κB. Clin Cancer Res 2013; 19:2917-28. [DOI: 10.1158/1078-0432.ccr-12-3258] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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456
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Wolfender JL, Queiroz EF, Hostettmann K. The importance of hyphenated techniques in the discovery of new lead compounds from nature. Expert Opin Drug Discov 2013; 1:237-60. [PMID: 23495845 DOI: 10.1517/17460441.1.3.237] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Nature represents an extraordinary reservoir of novel molecules and there is currently a resurgence of interest in natural products as a possible source of new lead compounds for introduction into therapeutical screening programmes. To discover new bioactive natural products, the dereplication of crude extracts performed prior to isolation work is of crucial importance for avoiding the tedious isolation of known constituents. In this respect, chemical screening strategies based on hyphenated techniques such as liquid chromatography-ultraviolet photodiode array detection, liquid chromatography-mass spectrometry, liquid chromatography tandom mass spectrometry and liquid chromatography-nuclear magnetic resonance (LC-NMR) are more and more extensively used. In the laboratory of Hostettmann's group, these analytical methods have been fully integrated into the isolation process and are used for the chemical screening of crude plant extracts, in complement with online or at-line bioassays, for rapid localisation and identification of new bioactive compounds. In this paper, possibilities and limitations of hyphenated techniques for de novo online natural product identification are discussed. As LC-NMR is playing a key role in this respect, the main part of the paper is dedicated to this technique. In particular, various ways of integrating NMR in the dereplication process are illustrated and strategies involving either direct or indirect hyphenation are presented.
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Affiliation(s)
- Jean-Luc Wolfender
- Laboratory of Pharmacognosy and Pytochemistry, School of Pharmaceutical Sciences, University of Geneva, Univerity of Lausanne, 30 quai Ernest-Ansermet, CH-1211, Geneva, Switzerland; †
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457
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Thommen C, Jana CK, Neuburger M, Gademann K. Syntheses of Taiwaniaquinone F and Taiwaniaquinol A via an Unusual Remote C–H Functionalization. Org Lett 2013; 15:1390-3. [DOI: 10.1021/ol4003652] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christophe Thommen
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Chandan Kumar Jana
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Markus Neuburger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Karl Gademann
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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458
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Pseudomonas putida are environmental reservoirs of antimicrobial resistance to β-lactamic antibiotics. World J Microbiol Biotechnol 2013; 29:1317-25. [PMID: 23420114 DOI: 10.1007/s11274-013-1295-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 02/14/2013] [Indexed: 10/27/2022]
Abstract
The adaptive flexibility of bacteria largely contributes to the emergence of antibiotic resistance, eventually leading to the predictable failure of current antimicrobial therapies. It is of utmost importance to improve current approaches and implement new ways to control bacterial growth and proliferation. A promising strategy lies in unraveling the antimicrobial resistance (AMR) dynamics in environmental reservoirs, namely in soil. Environmental microorganisms are antibiotic producers and generally also carriers of AMR mechanisms. Therefore, soil samples were collected from areas distinctly influenced by men: rural farms and urban fluvial shores. Globally, microbial communities collected in farms revealed the highest antibiotic resistance potential. Largely predominant Gram-negative isolates were further screened for their low susceptibility to β-lactamic agents, and found to belong to Pseudomonaceae family, with predominance of Pseudomonas putida (92 %). Minimal Inhibitory Concentration (MIC) was determined for five β-lactams and the distributive analysis of cefotaxime MIC performed, allowing the first report of Epidemiological Cut-OFF values for P. putida regarding such antibiotic. Hence, 46 % of the isolates from farms presented acquired resistance to cefotaxime, with fluvial strains presenting an acquisition of AMR in 22 % of the isolates. The response to β-lactams impact in P. putida is different from Pseudomonas aeruginosa's, the family type strain, showing that data determined for a species should only be extended to other bacteria with caution, even closely related. It becomes crucial to broaden present research, mainly focused on few pathogenic bacteria, to other microorganisms carrying relevant resistance tools or capable of genetic transfer to more virulent strains. Most available data on AMR so far has been obtained from studies performed in restricted clinical or veterinary context, showing the result of a strong selective pressure related to therapy but often disregarding the origin of the AMR mechanisms encountered. The strong impact that environmental microorganisms have (and probably already had in the past) on the evolution and spreading of AMR, is just beginning to be unveiled.
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459
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Ozaki T, Nishiyama M, Kuzuyama T. Novel tryptophan metabolism by a potential gene cluster that is widely distributed among actinomycetes. J Biol Chem 2013; 288:9946-9956. [PMID: 23430264 PMCID: PMC3617294 DOI: 10.1074/jbc.m112.436451] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The characterization of potential gene clusters is a promising strategy for the identification of novel natural products and the expansion of structural diversity. However, there are often difficulties in identifying potential metabolites because their biosynthetic genes are either silenced or expressed only at a low level. Here, we report the identification of a novel metabolite that is synthesized by a potential gene cluster containing an indole prenyltransferase gene (SCO7467) and a flavin-dependent monooxygenase (FMO) gene (SCO7468), which were mined from the genome of Streptomyces coelicolor A3(2). We introduced these two genes into the closely related Streptomyces lividans TK23 and analyzed the culture broths of the transformants. This process allowed us to identify a novel metabolite, 5-dimethylallylindole-3-acetonitrile (5-DMAIAN) that was overproduced in the transformant. Biochemical characterization of the recombinant SCO7467 and SCO7468 demonstrated the novel l-tryptophan metabolism leading to 5-DMAIAN. SCO7467 catalyzes the prenylation of l-tryptophan to form 5-dimethylallyl-l-tryptophan (5-DMAT). This enzyme is the first actinomycetes prenyltransferase known to catalyze the addition of a dimethylallyl group to the C-5 of tryptophan. SCO7468 then catalyzes the conversion of 5-DMAT into 5-dimethylallylindole-3-acetaldoxime (5-DMAIAOx). An aldoxime-forming reaction catalyzed by the FMO enzyme was also identified for the first time in this study. Finally, dehydration of 5-DMAIAOx presumably occurs to yield 5-DMAIAN. This study provides insight into the biosynthesis of prenylated indoles that have been purified from actinomycetes.
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Affiliation(s)
- Taro Ozaki
- Biotechnology Research Center, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Makoto Nishiyama
- Biotechnology Research Center, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Tomohisa Kuzuyama
- Biotechnology Research Center, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
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460
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Cragg GM, Newman DJ. Natural products: a continuing source of novel drug leads. Biochim Biophys Acta Gen Subj 2013; 1830:3670-95. [PMID: 23428572 DOI: 10.1016/j.bbagen.2013.02.008] [Citation(s) in RCA: 1604] [Impact Index Per Article: 145.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 01/30/2013] [Accepted: 02/05/2013] [Indexed: 12/14/2022]
Abstract
BACKGROUND Nature has been a source of medicinal products for millennia, with many useful drugs developed from plant sources. Following discovery of the penicillins, drug discovery from microbial sources occurred and diving techniques in the 1970s opened the seas. Combinatorial chemistry (late 1980s), shifted the focus of drug discovery efforts from Nature to the laboratory bench. SCOPE OF REVIEW This review traces natural products drug discovery, outlining important drugs from natural sources that revolutionized treatment of serious diseases. It is clear Nature will continue to be a major source of new structural leads, and effective drug development depends on multidisciplinary collaborations. MAJOR CONCLUSIONS The explosion of genetic information led not only to novel screens, but the genetic techniques permitted the implementation of combinatorial biosynthetic technology and genome mining. The knowledge gained has allowed unknown molecules to be identified. These novel bioactive structures can be optimized by using combinatorial chemistry generating new drug candidates for many diseases. GENERAL SIGNIFICANCE The advent of genetic techniques that permitted the isolation / expression of biosynthetic cassettes from microbes may well be the new frontier for natural products lead discovery. It is now apparent that biodiversity may be much greater in those organisms. The numbers of potential species involved in the microbial world are many orders of magnitude greater than those of plants and multi-celled animals. Coupling these numbers to the number of currently unexpressed biosynthetic clusters now identified (>10 per species) the potential of microbial diversity remains essentially untapped.
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Affiliation(s)
- Gordon M Cragg
- Division of Cancer Treatment and Diagnosis, Frederick National Laboratory for Cancer Research, Frederick, MD 21702-1201, USA
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461
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Hou X, Yuan X, Zhang B, Wang S, Chen Q. Screening active anti-breast cancer compounds from Cortex Magnolia officinalis
by 2DLC-MS. J Sep Sci 2013; 36:706-12. [DOI: 10.1002/jssc.201200896] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Revised: 10/25/2012] [Accepted: 11/01/2012] [Indexed: 12/15/2022]
Affiliation(s)
- Xiaofang Hou
- School of Medicine; Xi'an Jiaotong University; Xi'an P. R. China
| | - Xilong Yuan
- School of Medicine; Xi'an Jiaotong University; Xi'an P. R. China
| | - Bing Zhang
- School of Medicine; Xi'an Jiaotong University; Xi'an P. R. China
| | - Sicen Wang
- School of Medicine; Xi'an Jiaotong University; Xi'an P. R. China
| | - Qinhua Chen
- Dongfeng Hospital; Hubei University of Medicine; Shiyan P. R. China
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462
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Abstract
Intramolecular cycloadditions of bicyclo[1.1.0]butylalkyl-amines represent a rich source of novel heterocyclic scaffolds. As a function of the side chain attached to the amine, formal ene- or [2 + 2] cycloaddition products can be obtained in moderate to high yields. By suitable further functionalizations, a library of 3-azatricyclo[5.1.1.01,5]-nonanes was prepared and interrogated in 450 biological assays. This discovery collection was found to generate high hit rates and yet the individual samples demonstrated sufficient selectivity to fulfill robust lead criteria. These applications of bicyclo[1.1.0]butanes demonstrate that new synthetic chemistry and novel architectures are promising starting points for the generation of high-value discovery libraries.
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463
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Yang S, Xi Y, Zhu R, Wang L, Chen J, Yang Z. Asymmetric Total Syntheses of Ansamacrolactams (+)-Q-1047H-A-A and (+)-Q-1047H-R-A. Org Lett 2013; 15:812-5. [DOI: 10.1021/ol400038h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Shouliang Yang
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yumeng Xi
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Rong Zhu
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Lin Wang
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Jiahua Chen
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Zhen Yang
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
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464
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Ignatenko VA, Han Y, Tochtrop GP. Molecular library synthesis using complex substrates: expanding the framework of triterpenoids. J Org Chem 2013; 78:410-8. [PMID: 23245400 PMCID: PMC3903665 DOI: 10.1021/jo302211f] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The remodeling of a natural product core framework by means of diversity-oriented synthesis (DOS) is a valuable approach to access diverse/biologically relevant chemical space and to overcome the limitations of combinatorial-type compounds. Here we provide proof of principle and a thorough conformational analysis for a general strategy whereby the inherent complexity of a starting material is used to define the regio- and stereochemical outcomes of reactions in chemical library construction. This is in contrast to the traditional DOS logic employing reaction development and catalysis to drive library diversity.
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Affiliation(s)
- Vasily A. Ignatenko
- Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Yong Han
- Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Gregory P. Tochtrop
- Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
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465
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Qadri M, Johri S, Shah BA, Khajuria A, Sidiq T, Lattoo SK, Abdin MZ, Riyaz-Ul-Hassan S. Identification and bioactive potential of endophytic fungi isolated from selected plants of the Western Himalayas. SPRINGERPLUS 2013; 2:8. [PMID: 23420270 PMCID: PMC3568471 DOI: 10.1186/2193-1801-2-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2012] [Accepted: 01/04/2013] [Indexed: 02/04/2023]
Abstract
This study was conducted to characterize and explore the endophytic fungi of selected plants from the Western Himalayas for their bioactive potential. A total of 72 strains of endophytic fungi were isolated and characterized morphologically as well as on the basis of ITS1-5.8S-ITS2 ribosomal gene sequence acquisition and analyses. The fungi represented 27 genera of which two belonged to Basidiomycota, each representing a single isolate, while the rest of the isolates comprised of Ascomycetous fungi. Among the isolated strains, ten isolates could not be assigned to a genus as they displayed a maximum sequence similarity of 95% or less with taxonomically characterized organisms. Among the host plants, the conifers, Cedrus deodara, Pinus roxburgii and Abies pindrow harbored the most diverse fungi, belonging to 13 different genera, which represented almost half of the total genera isolated. Several extracts prepared from the fermented broth of these fungi demonstrated strong bioactivity against E. coli and S. aureus with the lowest IC50 of 18 μg/ml obtained with the extract of Trichophaea abundans inhabiting Pinus sp. In comparison, extracts from only three endophytes were significantly inhibitory to Candida albicans, an important fungal pathogen. Further, 24 endophytes inhibited three or more phytopathogens by at least 50% in co-culture, among a panel of seven test organisms. Extracts from 17 fungi possessed immuno-modulatory activities with five of them showing significant immune suppression as demonstrated by the in vitro lymphocyte proliferation assay. This study is an important step towards tapping the endophytic fungal diversity from the Western Himalayas and assessing their bioactive potential. Further studies on the selected endophytes may lead to the isolation of novel natural products for use in medicine, industry and agriculture.
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Affiliation(s)
- Masroor Qadri
- Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001 India
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466
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Shoaib HM, Muazzam AG, Mir A, Jung SY, Matin A. Evaluation of inhibitory potential of some selective methanolic plants extracts on biological characteristics of Acanthamoeba castellanii using human corneal epithelial cells in vitro. Parasitol Res 2013; 112:1179-88. [PMID: 23306385 DOI: 10.1007/s00436-012-3249-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Accepted: 12/11/2012] [Indexed: 12/13/2022]
Abstract
Acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. This is due to limited availability of effective anti-Acanthamoeba drugs. The objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological properties of Acanthamoeba castellanii (T4 genotype) and its cytotoxic effects on human corneal epithelial cells (HCEC). Using HCEC, it was observed that Acanthamoeba exhibited binding (>90 %) and cytotoxicity (>80 %) to host cells. However, plant crude extracts remarkably inhibited more than 70 and 60 % of Acanthamoeba binding and cytotoxicity to HCEC, respectively. It was further established that crude extracts (ranging from 0.1 to 1.5 mg/ml) exhibited amoebicidal effects, i.e., >50 % of trophozoites were killed/reduced at maximum dose (1.5 mg/ml) within 1 h incubation. However, the residual subpopulation remained static over longer incubations. Furthermore, growth assay demonstrated crude extracts inhibited >50 % Acanthamoeba numbers up to 7 days. Our results confirmed that plant crude extracts has inhibitory effects on Acanthamoeba growth and viability. Overall, these findings revealed that tested plant extracts is inhibitory to Acanthamoeba properties associated with pathogenesis. To the best of our knowledge, our findings demonstrated for the first time that selected methanol plant crude extracts exhibits inhibitory effects on biological properties of Acanthamoeba without any toxic effects on HCEC cells in vitro.
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Affiliation(s)
- Hafiz Muhammad Shoaib
- Department of Environmental Sciences, International Islamic University, Islamabad, 44000, Pakistan
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467
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Ryan SJ, Francis CL, Savage GP. N-Aryl Atropisomerism Induces Facial Selectivity in Benzonitrile Oxide Cycloadditions with Exocyclic Methylene Benzosultams. Aust J Chem 2013. [DOI: 10.1071/ch13270] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
N-aryl methylene benzo-fused sultams (2,3-dihydrobenzo[d]isothiazole 1,1-dioxides) underwent [3+2] cycloaddition with benzonitrile oxide to give 5-spiro isoxazoline adducts with complete regioselectivity. Steric hindrance by atropisomerism around the N-aryl bond induced facial selectivity in these cycloadditions.
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468
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469
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HPLC Quantification of Phenolic Acids from Vetiveria zizanioides (L.) Nash and Its Antioxidant and Antimicrobial Activity. JOURNAL OF PHARMACEUTICS 2013; 2013:270472. [PMID: 26555971 PMCID: PMC4590811 DOI: 10.1155/2013/270472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 01/31/2013] [Accepted: 01/31/2013] [Indexed: 11/17/2022]
Abstract
Extraction procedure was standardized and for the soluble, glycoside, and wall-bound fractions of phenolic acids from Vetiveria zizanioides. The water soluble alkaline extract which represents the cell wall-bound fraction contained the highest amount of phenolic acids (2.62 ± 1.2 μM/g fwt GA equivalents). Increased phenolic content in the cell wall indicates more lignin deposition which has an important role in plant defense and stress mitigation. Antioxidant property expressed as percentage TEAC value obtained by ABTS assay was correlated with the amount of phenolic acids and showed a Pearson's coefficient 0.988 (significant at 0.01 level). The compounds p-coumaric acid, p-dihydroxybenzoic acid, and ferulic acid were detected in the acidic extracts by HPLC analysis. The plant extracts exhibited considerable antimicrobial activity against tested bacterial and fungal strains.
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470
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Francis CL, Kenny PW, Dolezal O, Saubern S, Kruger M, Savage GP, Peat TS, Ryan JH. Construction of the CSIRO Fragment Library. Aust J Chem 2013. [DOI: 10.1071/ch13325] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A fundamental component of a successful fragment screening program is a productive fragment library, one that delivers hit fragments with potential for pharmaceutical development. A proprietary fragment library was developed by identifying and extracting subsets of CSIRO’s Compound Collection using two complimentary approaches. Over time, the use of surface plasmon resonance as a front-line screening tool has enabled identification and exclusion of problematic compounds and led to a more reliable fragment screening library.
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471
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Devadasu VR, Bhardwaj V, Kumar MNVR. Can controversial nanotechnology promise drug delivery? Chem Rev 2012; 113:1686-735. [PMID: 23276295 DOI: 10.1021/cr300047q] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Venkat Ratnam Devadasu
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, United Kingdom
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472
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Sgarbossa A. Natural biomolecules and protein aggregation: emerging strategies against amyloidogenesis. Int J Mol Sci 2012; 13:17121-37. [PMID: 23242152 PMCID: PMC3546742 DOI: 10.3390/ijms131217121] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 12/12/2012] [Accepted: 12/12/2012] [Indexed: 01/13/2023] Open
Abstract
Biomolecular self-assembly is a fundamental process in all organisms. As primary components of the life molecular machinery, proteins have a vast array of resources available to them for self-assembly in a functional structure. Protein self-assembly, however, can also occur in an aberrant way, giving rise to non-native aggregated structures responsible for severe, progressive human diseases that have a serious social impact. Different neurodegenerative disorders, like Huntington's, Alzheimer's, and spongiform encephalopathy diseases, have in common the presence of insoluble protein aggregates, generally termed "amyloid," that share several physicochemical features: a fibrillar morphology, a predominantly beta-sheet secondary structure, birefringence upon staining with the dye Congo red, insolubility in common solvents and detergents, and protease resistance. Conformational constrains, hydrophobic and stacking interactions can play a key role in the fibrillogenesis process and protein-protein and peptide-peptide interactions-resulting in self-assembly phenomena of peptides yielding fibrils-that can be modulated and influenced by natural biomolecules. Small organic molecules, which possess both hydrophilic and hydrophobic moieties able to bind to peptide/protein molecules through hydrogen bonds and hydrophobic and aromatic interactions, are potential candidates against amyloidogenesis. In this review some significant case examples will be critically discussed.
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Affiliation(s)
- Antonella Sgarbossa
- Institute of Biophysics, CNR, Italian National Research Council, Via G. Moruzzi 1, 56124 Pisa, Italy.
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473
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Deng X, Kong LM, Zhao Y, He J, Peng LY, Li Y, Zhao QS. Exploring of drug leads from diversity-oriented Michael-acceptor library derived from natural products. NATURAL PRODUCTS AND BIOPROSPECTING 2012. [PMCID: PMC4131632 DOI: 10.1007/s13659-012-0071-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Affiliation(s)
- Xu Deng
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
- />Graduate University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Ling-Mei Kong
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
- />Graduate University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yu Zhao
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
| | - Juan He
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
| | - Li-Yan Peng
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
| | - Yan Li
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
| | - Qin-Shi Zhao
- />State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201 China
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474
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Polyether ionophores—promising bioactive molecules for cancer therapy. Bioorg Med Chem Lett 2012; 22:7002-10. [DOI: 10.1016/j.bmcl.2012.09.046] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/13/2012] [Accepted: 09/15/2012] [Indexed: 01/06/2023]
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475
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Abstract
INTRODUCTION The apparent productivity crisis in the pharmaceutical industry and the economic and political rise of China have contributed to renewed interest in the application of Chinese medicine for drug discovery. AREAS COVERED The author presents an overview of the historical development and basic principles of theory and practice of Chinese herbal medicine, its materia medica and prescription formulas, and discusses the motivation for and rationale of its application to drug discovery. Furthermore, the author distinguishes the five main approaches to drug discovery from Chinese herbal medicine, based on the decreasing amount and detail of historical and clinical Chinese medicine knowledge that informed the research effort. EXPERT OPINION Many compounds that have been isolated from the Chinese materia medica exhibit pharmacological activities comparable to pharmaceutical drugs. With the exception of the antimalarial drug artemisinin, however, this knowledge has not led to the successful development of new drugs outside of China. The chance of success in a Chinese medicine-based drug discovery effort will be increased by consideration of the empirical knowledge that has been documented over many centuries in the historical materia medica and prescription literature. Most Chinese medicine-derived compounds affect more than one target and do not correspond to the one compound/one-target drug discovery paradigm. A new frontier is opening up with the development of drugs consisting of combinations of multiple compounds acting on multiple targets under the paradigm of network pharmacology. The ancient practice of combining multiple drugs in prescription formulas can serve as inspirational analogy and a practical guide.
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Affiliation(s)
- Nikolaus J Sucher
- Science, Technology, Engineering & Math (S.T.E.M), Roxbury Community College, Roxbury Crossing, MA 02120, USA.
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476
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Wei H, Qiao C, Liu G, Yang Z, Li CC. Stereoselective Total Syntheses of (−)-Flueggine A and (+)-Virosaine B. Angew Chem Int Ed Engl 2012; 52:620-4. [DOI: 10.1002/anie.201208261] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2012] [Indexed: 11/06/2022]
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477
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Wei H, Qiao C, Liu G, Yang Z, Li CC. Stereoselective Total Syntheses of (−)-Flueggine A and (+)-Virosaine B. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201208261] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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478
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Major DT, Weitman M. Electrostatically guided dynamics--the root of fidelity in a promiscuous terpene synthase? J Am Chem Soc 2012; 134:19454-62. [PMID: 23101787 DOI: 10.1021/ja308295p] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Terpene cyclases are responsible for the initial cyclization cascade in the multistep synthesis of more than 60,000 known natural products. This abundance of compounds is generated using a very limited pool of substrates based on linear isoprenoids. The astounding chemodiversity obtained by terpene cyclases suggests a tremendous catalytic challenge to these often promiscuous enzymes. In the current study we present a detailed mechanistic view of the biosynthesis of the monoterpene bornyl diphosphate (BPP) from geranyl diphosphate by BPP synthase using state of the art simulation methods. We identify the bornyl cation as an enzyme-induced bifurcation point on the multidimensional free energy surface, connecting between the product BPP and the side product camphene. Chemical dynamics simulations suggest that the active site diphosphate moiety steers reaction trajectories toward product formation. Nonetheless, chemical dynamics is not precise enough for exclusive product formation, providing a rationale for the lack of fidelity in this promiscuous terpene cyclase.
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Affiliation(s)
- Dan Thomas Major
- Department of Chemistry and the Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel.
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479
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Wang J, Gao R, Li Q, Xie S, Zhao J, Wang C. Synthesis, Cytotoxicity, and Cell Death Profile of Polyaminoanthraquinones as Antitumor Agents. Chem Biol Drug Des 2012; 80:909-17. [DOI: 10.1111/cbdd.12038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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480
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Zhang Z, Guan N, Li T, Mais DE, Wang M. Quality control of cell-based high-throughput drug screening. Acta Pharm Sin B 2012. [DOI: 10.1016/j.apsb.2012.03.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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481
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Trader DJ, Carlson EE. Chemoselective hydroxyl group transformation: an elusive target. MOLECULAR BIOSYSTEMS 2012; 8:2484-93. [PMID: 22695722 PMCID: PMC3430791 DOI: 10.1039/c2mb25122a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The selective reaction of one functional group in the presence of others is not a trivial task. A noteworthy amount of research has been dedicated to the chemoselective reaction of the hydroxyl moiety. This group is prevalent in many biologically important molecules including natural products and proteins. However, targeting the hydroxyl group is difficult for many reasons including its relatively low nucleophilicity in comparison to other ubiquitous functional groups such as amines and thiols. Additionally, many of the developed chemoselective reactions cannot be used in the presence of water. Despite these complications, chemoselective transformation of the hydroxyl moiety has been utilized in the synthesis of complex natural product derivatives, the reaction of tyrosine residues in proteins, the isolation of natural products and is the mechanism of action of myriad drugs. Here, methods for selective targeting of this group, as well as applications of several devised methods, are described.
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Affiliation(s)
- Darci J. Trader
- Department of Chemistry, Indiana University, 212 S. Hawthorne Drive Bloomington, IN 47405
| | - Erin E. Carlson
- Department of Chemistry, Indiana University, 212 S. Hawthorne Drive Bloomington, IN 47405
- Department of Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Drive Bloomington, IN 47405
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482
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Al-Musayeib NM, Mothana RA, Al-Massarani S, Matheeussen A, Cos P, Maes L. Study of the in vitro antiplasmodial, antileishmanial and antitrypanosomal activities of medicinal plants from Saudi Arabia. Molecules 2012; 17:11379-90. [PMID: 23011279 PMCID: PMC6268159 DOI: 10.3390/molecules171011379] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 09/15/2012] [Accepted: 09/18/2012] [Indexed: 11/16/2022] Open
Abstract
The present study investigated the in vitro antiprotozoal activity of sixteen selected medicinal plants. Plant materials were extracted with methanol and screened in vitro against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. Cytotoxic activity was determined against MRC-5 cells to assess selectivity. The criterion for activity was an IC₅₀ < 10 μg/mL (<5 μg/mL for T. brucei) and a selectivity index of ≥4. Antiplasmodial activity was found in the extracts of Prosopis juliflora and Punica granatum. Antileishmanial activity against L. infantum was demonstrated in Caralluma sinaica and Periploca aphylla. Amastigotes of T. cruzi were affected by the methanol extract of Albizia lebbeck pericarp, Caralluma sinaica, Periploca aphylla and Prosopius juliflora. Activity against T. brucei was obtained in Prosopis juliflora. Cytotoxicity (MRC-5 IC₅₀ < 10 μg/mL) and hence non-specific activities were observed for Conocarpus lancifolius.
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Affiliation(s)
- Nawal M. Al-Musayeib
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia; (N.M.A.-M.); (S.A.-M.)
| | - Ramzi A. Mothana
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia; (N.M.A.-M.); (S.A.-M.)
- Department of Pharmacognosy, Faculty of Pharmacy, Sana’a University, P.O. Box 33039, Sana’a, Yemen
| | - Shaza Al-Massarani
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia; (N.M.A.-M.); (S.A.-M.)
| | - An Matheeussen
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Antwerp University, Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium; (P.C.); ; (L.M.)
| | - Paul Cos
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Antwerp University, Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium; (P.C.); ; (L.M.)
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Antwerp University, Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium; (P.C.); ; (L.M.)
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483
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484
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Chanti Babu D, Bhujanga Rao C, Ramesh D, Raghavendra Swamy S, Venkateswarlu Y. Total synthesis of the aromatase inhibitor dihydroisocoumarin via protective opening of lactones. Tetrahedron Lett 2012. [DOI: 10.1016/j.tetlet.2012.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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485
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Kim DH, Hong BN, Le HT, Hong HN, Lim CW, Park KH, Kim TW, Kang TH. Small molecular weight PEGylation of diosgenin in an in vivo animal study for diabetic auditory impairment treatment. Bioorg Med Chem Lett 2012; 22:4609-12. [DOI: 10.1016/j.bmcl.2012.05.094] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 05/15/2012] [Accepted: 05/29/2012] [Indexed: 02/03/2023]
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486
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Chen X, Cao Y, Lv D, Zhu Z, Zhang J, Chai Y. Comprehensive two-dimensional HepG2/cell membrane chromatography/monolithic column/time-of-flight mass spectrometry system for screening anti-tumor components from herbal medicines. J Chromatogr A 2012; 1242:67-74. [DOI: 10.1016/j.chroma.2012.04.034] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Revised: 04/07/2012] [Accepted: 04/11/2012] [Indexed: 12/28/2022]
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487
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Antimicrobial Activity of Essential Oils against Streptococcus mutans and their Antiproliferative Effects. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:751435. [PMID: 22685486 PMCID: PMC3368214 DOI: 10.1155/2012/751435] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 02/26/2012] [Indexed: 11/17/2022]
Abstract
This study aimed to evaluate the activity of essential oils (EOs) against Streptococcus mutans biofilm by chemically characterizing their fractions responsible for biological and antiproliferative activity. Twenty EO were obtained by hydrodistillation and submitted to the antimicrobial assay (minimum inhibitory (MIC) and bactericidal (MBC) concentrations) against S. mutans UA159. Thin-layer chromatography and gas chromatography/mass spectrometry were used for phytochemical analyses. EOs were selected according to predetermined criteria and fractionated using dry column; the resulting fractions were assessed by MIC and MBC, selected as active fractions, and evaluated against S. mutans biofilm. Biofilms formed were examined using scanning electron microscopy. Selected EOs and their selected active fractions were evaluated for their antiproliferative activity against keratinocytes and seven human tumor cell lines. MIC and MBC values obtained for EO and their active fractions showed strong antimicrobial activity. Chemical analyses mainly showed the presence of terpenes. The selected active fractions inhibited S. mutans biofilm formation (P < 0.05) did not affect glycolytic pH drop and were inactive against keratinocytes, normal cell line. In conclusion, EO showed activity at low concentrations, and their selected active fractions were also effective against biofilm formed by S. mutans and human tumor cell lines.
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488
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Finefield JM, Sherman DH, Kreitman M, Williams RM. Enantiomeric natural products: occurrence and biogenesis. Angew Chem Int Ed Engl 2012; 51:4802-36. [PMID: 22555867 PMCID: PMC3498912 DOI: 10.1002/anie.201107204] [Citation(s) in RCA: 201] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Indexed: 01/07/2023]
Abstract
In nature, chiral natural products are usually produced in optically pure form-however, occasionally both enantiomers are formed. These enantiomeric natural products can arise from a single species or from different genera and/or species. Extensive research has been carried out over the years in an attempt to understand the biogenesis of naturally occurring enantiomers; however, many fascinating puzzles and stereochemical anomalies still remain.
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489
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Lachance H, Wetzel S, Kumar K, Waldmann H. Charting, navigating, and populating natural product chemical space for drug discovery. J Med Chem 2012; 55:5989-6001. [PMID: 22537178 DOI: 10.1021/jm300288g] [Citation(s) in RCA: 260] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Natural products are a heterogeneous group of compounds with diverse, yet particular molecular properties compared to synthetic compounds and drugs. All relevant analyses show that natural products indeed occupy parts of chemical space not explored by available screening collections while at the same time largely adhering to the rule-of-five. This renders them a valuable, unique, and necessary component of screening libraries used in drug discovery. With ChemGPS-NP on the Web and Scaffold Hunter two tools are available to the scientific community to guide exploration of biologically relevant NP chemical space in a focused and targeted fashion with a view to guide novel synthesis approaches. Several of the examples given illustrate the possibility of bridging the gap between computational methods and compound library synthesis and the possibility of integrating cheminformatics and chemical space analyses with synthetic chemistry and biochemistry to successfully explore chemical space for the identification of novel small molecule modulators of protein function.The examples also illustrate the synergistic potential of the chemical space concept and modern chemical synthesis for biomedical research and drug discovery. Chemical space analysis can map under explored biologically relevant parts of chemical space and identify the structure types occupying these parts. Modern synthetic methodology can then be applied to efficiently fill this “virtual space” with real compounds.From a cheminformatics perspective, there is a clear demand for open-source and easy to use tools that can be readily applied by educated nonspecialist chemists and biologists in their daily research. This will include further development of Scaffold Hunter, ChemGPS-NP, and related approaches on the Web. Such a “cheminformatics toolbox” would enable chemists and biologists to mine their own data in an intuitive and highly interactive process and without the need for specialized computer science and cheminformatics expertise. We anticipate that it may be a viable, if not necessary, step for research initiatives based on large high-throughput screening campaigns,in particular in the pharmaceutical industry, to make the most out of the recent advances in computational tools in order to leverage and take full advantage of the large data sets generated and available in house. There are “holes” in these data sets that can and should be identified and explored by chemistry and biology.
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Affiliation(s)
- Hugo Lachance
- Departmen of Chemical Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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490
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Finefield JM, Sherman DH, Kreitman M, Williams RM. Enantiomere Naturstoffe: Vorkommen und Biogenese. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201107204] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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491
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Li Y, Ma Y, Zhang L, Guo F, Ren L, Yang R, Li Y, Lou H. In vivo inhibitory effect on the biofilm formation of Candida albicans by liverwort derived riccardin D. PLoS One 2012; 7:e35543. [PMID: 22545115 PMCID: PMC3335839 DOI: 10.1371/journal.pone.0035543] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 03/18/2012] [Indexed: 01/09/2023] Open
Abstract
Riccardin D, a macrocyclic bisbibenzyl isolated from Chinese liverwort Dumortiera hirsute, has been proved to have inhibitory effect on biofilms formation of Candida albicans in in vitro study. Our present study aims to investigate the in vivo effect and mechanisms of riccardin D against C. albicans biofilms when used alone or in combination with clinical using antifungal agent fluconazole. XTT reduction assay revealed riccardin D had both prophylactic and therapeutic effect against C. albicans biofilms formation in a dose-dependent manner when using a central venous catheter related infective animal model. Scanning electron microscope and laser confocal scanning microscope showed that the morphology of biofilms was altered remarkably after riccardin D treatment, especially hypha growth inhibition. To uncover the underlying molecular mechanisms, quantitative real-time RT-PCR was performed to observe the variation of related genes. The downregulation of hypha-specific genes such as ALS1, ALS3, ECE1, EFG1, HWP1 and CDC35 following riccardin D treatment suggested riccardin D inhibited the Ras-cAMP-Efg pathway to retard the hypha formation, then leading to the defect of biofilms maturation. Moreover, riccardin D displayed an increased antifungal activity when administered in combination with fluconazole. Our study provides a potential clinical application to eliminate the biofilms of relevant pathogens.
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Affiliation(s)
- Yan Li
- School of Pharmaceutical Sciences, Shandong University, Jinan, China
- Department of Pharmacy, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Yukui Ma
- Shandong Pharmaceutical Industry Research Institute, Jinan, China
| | - Li Zhang
- School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Feng Guo
- Shandong Pharmaceutical Industry Research Institute, Jinan, China
| | - Lei Ren
- Department of Pharmacy, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Rui Yang
- Department of Pharmacy, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Ying Li
- School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Hongxiang Lou
- School of Pharmaceutical Sciences, Shandong University, Jinan, China
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492
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Al-Musayeib NM, Mothana RA, Matheeussen A, Cos P, Maes L. In vitro antiplasmodial, antileishmanial and antitrypanosomal activities of selected medicinal plants used in the traditional Arabian Peninsular region. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 12:49. [PMID: 22520595 PMCID: PMC3493369 DOI: 10.1186/1472-6882-12-49] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 04/13/2012] [Indexed: 11/25/2022]
Abstract
Background Worldwide particularly in developing countries, a large proportion of the population is at risk for tropical parasitic diseases. Several medicinal plants are still used traditionally against protozoal infections in Yemen and Saudi Arabia. Thus the present study investigated the in vitro antiprotozoal activity of twenty-five plants collected from the Arabian Peninsula. Methods Plant materials were extracted with methanol and screened in vitro against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. Cytotoxic activity was determined against MRC-5 cells to assess selectivity. The criterion for activity was an IC50 < 10 μg/ml (<5 μg/ml for T. brucei) and selectivity index of >4. Results Antiplasmodial activity was found in the extracts of Chrozophora oblongifolia, Ficus ingens, Lavandula dentata and Plectranthus barbatus. Amastigotes of T. cruzi were affected by Grewia erythraea, L. dentata, Tagetes minuta and Vernonia leopoldii. Activity against T. brucei was obtained in G. erythraea, L. dentata, P. barbatus and T. minuta. No relevant activity was found against L. infantum. High levels of cytotoxicity (MRC-5 IC50 < 10 μg/ml) and hence non-specific activities were noted in Cupressus sempervirens, Kanahia laniflora and Kniphofia sumarae. Conclusion The results endorse that medicinal plants can be promising sources of natural products with antiprotozoal activity potential. The results support to some extent the traditional uses of some plants for the treatment of parasitic protozoal diseases.
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493
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Bérdy J. Thoughts and facts about antibiotics: where we are now and where we are heading. J Antibiot (Tokyo) 2012; 65:385-95. [PMID: 22511224 DOI: 10.1038/ja.2012.27] [Citation(s) in RCA: 535] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The declining trends in microbial metabolite and natural products research and the refocusing of this research area are discussed. Renewing natural products research requires inexhaustible natural resources, as well as new genetic techniques and microbial sources, including endophytic microbes. The numbers of known bioactive metabolites are summarized according to their microbiological origin, biological activities and chemical structures. Synthetic and natural product-based libraries are also compared. Importantly, the wide range of microbial metabolite bioactivities, future trends and the importance of prioritizing natural products over synthetic compounds are emphasized.
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494
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Chemical composition and amoebicidal activity of Croton pallidulus, Croton ericoides, and Croton isabelli(Euphorbiaceae) essential oils. Parasitol Res 2012; 111:961-6. [DOI: 10.1007/s00436-012-2918-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 03/26/2012] [Indexed: 11/30/2022]
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495
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A lactose-binding lectin from the marine sponge Cinachyrella apion (Cal) induces cell death in human cervical adenocarcinoma cells. Mar Drugs 2012; 10:727-743. [PMID: 22690140 PMCID: PMC3366672 DOI: 10.3390/md10040727] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 02/23/2012] [Accepted: 03/05/2012] [Indexed: 01/03/2023] Open
Abstract
Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5–10 µg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC50 (10 µg/mL) for both trials and twice the IC50 for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer.
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496
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Abstract
This review covers the literature on the chemically mediated ecology of cyanobacteria, including ultraviolet radiation protection, feeding-deterrence, allelopathy, resource competition, and signalling. To highlight the chemical and biological diversity of this group of organisms, evolutionary and chemotaxonomical studies are presented. Several technologically relevant aspects of cyanobacterial chemical ecology are also discussed.
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Affiliation(s)
- Pedro N Leão
- CIIMAR/CIMAR, Center for Marine and Environmental Research, University of Porto, Rua dos Bragas 289, 4050-123, Porto, Portugal.
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497
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Chemoselective synthesis of ketones and ketimines by addition of organometallic reagents to secondary amides. Nat Chem 2012; 4:228-34. [PMID: 22354438 DOI: 10.1038/nchem.1268] [Citation(s) in RCA: 202] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 01/09/2012] [Indexed: 12/23/2022]
Abstract
The development of efficient and selective transformations is crucial in synthetic chemistry as it opens new possibilities in the total synthesis of complex molecules. Applying such reactions to the synthesis of ketones is of great importance, as this motif serves as a synthetic handle for the elaboration of numerous organic functionalities. In this context, we report a general and chemoselective method based on an activation/addition sequence on secondary amides allowing the controlled isolation of structurally diverse ketones and ketimines. The generation of a highly electrophilic imidoyl triflate intermediate was found to be pivotal in the observed exceptional functional group tolerance, allowing the facile addition of readily available Grignard and diorganozinc reagents to amides, and avoiding commonly observed over-addition or reduction side reactions. The methodology has been applied to the formal synthesis of analogues of the antineoplastic agent Bexarotene and to the rapid and efficient synthesis of unsymmetrical diketones in a one-pot procedure.
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498
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Liu K, Guo TL, Chojnacki J, Lee HG, Wang X, Siedlak SL, Rao W, Zhu X, Zhang S. Bivalent ligand containing curcumin and cholesterol as fluorescence probe for Aβ plaques in Alzheimer's disease. ACS Chem Neurosci 2012; 3:141-146. [PMID: 22685625 DOI: 10.1021/cn200122j] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A recently developed bivalent ligand BMAOI 14 (7) has been evaluated for its capability to label and detect aggregated β-amyloid (Aβ) peptide as a fluorescent probe. This probe contains curcumin as the Aβ recognition moiety and cholesterol as an anchorage to the neuronal cell membrane/lipid rafts. The results demonstrate that 7 binds to the monomers, oligomers as well as fibrils of Aβ42 with low micromolar to submicromolar binding affinities. This chemical probe also has many of the required optical properties for use in imaging and can rapidly cross the blood-brain barrier (BBB) in vivo. Furthermore, 7 specifically binds to Aβ plaques in both AD human patients and APP transgenic mouse brain tissues. Collectively, these results suggest that 7 is a strong candidate as an Aβ-imaging agent and encourage further optimization of 7 as a new lead to develop the next generation of Aβ-imaging probes.
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Affiliation(s)
- Kai Liu
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | - Tai L. Guo
- Department
of Pharmacology and
Toxicology, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Jeremy Chojnacki
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | - Hyoung-Gon Lee
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Xinglong Wang
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Sandra L. Siedlak
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Wei Rao
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Shijun Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia
23284, United States
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499
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Keller TL, Zocco D, Sundrud MS, Hendrick M, Edenius M, Yum J, Kim YJ, Lee HK, Cortese JF, Wirth DF, Dignam JD, Rao A, Yeo CY, Mazitschek R, Whitman M. Halofuginone and other febrifugine derivatives inhibit prolyl-tRNA synthetase. Nat Chem Biol 2012; 8:311-7. [PMID: 22327401 PMCID: PMC3281520 DOI: 10.1038/nchembio.790] [Citation(s) in RCA: 282] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 11/22/2011] [Indexed: 01/01/2023]
Abstract
Febrifugine, one of the fifty fundamental herbs of traditional Chinese medicine, has been characterized for its therapeutic activity whilst its molecular target has remained unknown. Febrifugine derivatives have been used to treat malaria, cancer, fibrosis, and inflammatory disease. We recently demonstrated that halofuginone (HF), a widely studied derivative of febrifugine, inhibits the development of Th17-driven autoimmunity in a mouse model of multiple sclerosis by activating the amino acid response pathway (AAR). Here we show that HF binds glutamyl-prolyl-tRNA synthetase (EPRS) inhibiting prolyl-tRNA synthetase activity; this inhibition is reversed by the addition of exogenous proline or EPRS. We further show that inhibition of EPRS underlies the broad bioactivities of this family of natural products. This work both explains the molecular mechanism of a promising family of therapeutics, and highlights the AAR pathway as an important drug target for promoting inflammatory resolution.
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Affiliation(s)
- Tracy L Keller
- Department of Developmental Biology, Harvard School of Dental Medicine, Boston, Massachusetts, USA.
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500
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Tong R, Cheng J. Zinc complex mediated regioselective O-acylation of therapeutic agents. Chem Sci 2012. [DOI: 10.1039/c2sc20239e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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