51
|
Vanzolini KL, Vieira LCC, Corrêa AG, Moaddel R, Cass QB. Acetylcholinesterase immobilized on modified magnetic beads as a tool for screening a compound library. Mikrochim Acta 2015. [DOI: 10.1007/s00604-015-1562-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
52
|
He B, Hu J, Zhang X, Lin H. Thiomyristoyl peptides as cell-permeable Sirt6 inhibitors. Org Biomol Chem 2015; 12:7498-502. [PMID: 25163004 DOI: 10.1039/c4ob00860j] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Sirtuins regulate a variety of biological pathways and inhibitors of sirtuins have been actively pursued as tool compounds to study sirtuin biology and as potential therapeutics. Here we demonstrate that thiomyristoyl peptides are potent and cell-permeable inhibitors of Sirt6, one of the seven human sirtuins, and will serve as the starting point for the development of more specific Sirt6 inhibitors.
Collapse
Affiliation(s)
- Bin He
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA.
| | | | | | | |
Collapse
|
53
|
Fabrication of enzyme-immobilized halloysite nanotubes for affinity enrichment of lipase inhibitors from complex mixtures. J Chromatogr A 2015; 1392:20-7. [PMID: 25798866 DOI: 10.1016/j.chroma.2015.03.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/28/2015] [Accepted: 03/02/2015] [Indexed: 11/23/2022]
Abstract
Lipase is the key enzyme for catalyzing triglyceride hydrolysis in vivo, and lipase inhibitors have been used in the management of obesity. We present the first report on the use of lipase-adsorbed halloysite nanotubes as an efficient medium for the selective enrichment of lipase inhibitors from natural products. A simple and rapid approach was proposed to fabricate lipase-adsorbed nanotubes through electrostatic interaction. Results showed that more than 85% lipase was adsorbed into nanotubes in 90 min, and approximately 80% of the catalytic activity was maintained compared with free lipase. The specificity and reproducibility of the proposed approach were validated by screening a known lipase inhibitor (i.e., orlistat) from a mixture that contains active and inactive compounds. Moreover, we applied this approach with high performance liquid chromatography-mass spectrometry technique to screen lipase inhibitors from the Magnoliae cortex extract, a medicinal plant used for treating obesity. Two novel biphenyl-type natural lipase inhibitors magnotriol A and magnaldehyde B were identified, and their IC50 values were determined as 213.03 and 96.96 μM, respectively. The ligand-enzyme interactions of magnaldehyde B were further investigated by molecular docking. Our findings proved that enzyme-adsorbed nanotube could be used as a feasible and selective affinity medium for the rapid screening of enzyme inhibitors from complex mixtures.
Collapse
|
54
|
Chen Y, Chen Z, Wang Y. Immobilized magnetic beads-based multi-target affinity selection coupled with HPLC-MS for screening active compounds from traditional Chinese medicine and natural products. Methods Mol Biol 2015; 1286:121-9. [PMID: 25749951 DOI: 10.1007/978-1-4939-2447-9_11] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Screening and identifying active compounds from traditional Chinese medicine (TCM) and other natural products plays an important role in drug discovery. Here, we describe a magnetic beads-based multi-target affinity selection-mass spectrometry approach for screening bioactive compounds from natural products. Key steps and parameters including activation of magnetic beads, enzyme/protein immobilization, characterization of functional magnetic beads, screening and identifying active compounds from a complex mixture by LC/MS, are illustrated. The proposed approach is rapid and efficient in screening and identification of bioactive compounds from complex natural products.
Collapse
Affiliation(s)
- Yaqi Chen
- Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Zijingang Campus, 866 Yuhangtang Rd, Hangzhou, 310058, China
| | | | | |
Collapse
|
55
|
Deng X, Shi S, Li S, Yang T. Magnetic ligand fishing combination with high-performance liquid chromatography–diode array detector–mass spectrometry to screen and characterize cyclooxygenase-2 inhibitors from green tea. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 973C:55-60. [DOI: 10.1016/j.jchromb.2014.10.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/18/2014] [Accepted: 10/08/2014] [Indexed: 11/27/2022]
|
56
|
Magnetic separation techniques in sample preparation for biological analysis: A review. J Pharm Biomed Anal 2014; 101:84-101. [DOI: 10.1016/j.jpba.2014.04.017] [Citation(s) in RCA: 187] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 04/10/2014] [Accepted: 04/14/2014] [Indexed: 11/16/2022]
|
57
|
Zhu YT, Jia YW, Liu YM, Liang J, Ding LS, Liao X. Lipase ligands in Nelumbo nucifera leaves and study of their binding mechanism. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:10679-10686. [PMID: 25328123 DOI: 10.1021/jf503687e] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Lotus (Nelumbo nucifera) leaves have been widely used in weight-loss foods to prevent obesity in China. In this work, a facile procedure based on ligand fishing was developed to isolate and identify lipase inhibitors present in lotus leaves. Highly stable and active lipase-Fe3O4 superparamagnetic nanoparticle conjugates (LMNPs) were prepared and used as baits. Two flavonoids in lotus leaf extract were found to bind to the baits and were identified as quercetin-3-O-β-d-arabinopyranosyl-(1→2)- β-d-galactopyranoside (1) and quercetin-3-O-β-d-glucuronide (4) based on electrospray ionization-mass spectrometric analyses. Their 50% inhibitory concentrations on lipase (IC50) were 52.9 ± 3.2 and 17.1 ± 1.5 μg/mL, respectively. In addition, they were found to significantly quench the fluorescence of lipase, suggesting their strong affinities with this enzyme, which was further evidenced by molecular docking. Ligand fishing based on LMNPs shows great power for fast screening and identification of lipase inhibitors present in edible and medicinal plants.
Collapse
Affiliation(s)
- Yuan-Ting Zhu
- Chengdu Institute of Biology, Chinese Academy of Sciences , Chengdu 610041, China
| | | | | | | | | | | |
Collapse
|
58
|
Singh N, Ravichandran S, Spelman K, Fugmann SD, Moaddel R. The identification of a novel SIRT6 modulator from Trigonella foenum-graecum using ligand fishing with protein coated magnetic beads. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 968:105-11. [PMID: 24704183 PMCID: PMC4127357 DOI: 10.1016/j.jchromb.2014.03.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 03/06/2014] [Accepted: 03/09/2014] [Indexed: 10/25/2022]
Abstract
SIRT6 is a histone deacetylase that has been proposed as a potential therapeutic target for metabolic disorders and the prevention of age-associated diseases. Thus the identification of compounds that modulate SIRT6 activity could be of great therapeutic importance. We have previously developed an H3K9 deacetylation guided assay with SIRT6 coated magnetic beads (SIRT6-MB). With the developed assay, we identified quercetin, naringenin and vitexin as SIRT6 inhibitors from T. foenum-graecum seed extract using a candidate approach. Currently, the predominant method for the identification of active compounds from a plant extract is carried out through a dereplication process. A novel targeted approach for the direct identification of active compounds from a complex matrix could save time and resources. Herein, we report the application of the SIRT6-MB for 'fishing' experiments utilizing T. foenum-graecum seed extract. In which orientin, and seventeen other compounds were identified as SIRT6 binders. This is the first use of this method for 'fishing' out active ligands from a botanical matrix, and sets the basis for the identification of active compounds from a complex matrix.
Collapse
Affiliation(s)
- N Singh
- Biomedical Research Center, National institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - S Ravichandran
- Advanced Biomedical Computing Center, Information Systems Program, Frederick National Laboratory for Cancer Research (FNLCR), Frederick, MD 21702, USA
| | - K Spelman
- Health, Education & Research in Botanical Medicine, 2209 Dollarhide Way, Ashland, OR 97520, USA
| | - S D Fugmann
- Department of Biomedical Sciences, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Taiwan
| | - R Moaddel
- Biomedical Research Center, National institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA.
| |
Collapse
|
59
|
Chen X, Cao Y, Zhang H, Zhu Z, Liu M, Liu H, Ding X, Hong Z, Li W, Lv D, Wang L, Zhuo X, Zhang J, Xie XQ, Chai Y. Comparative normal/failing rat myocardium cell membrane chromatographic analysis system for screening specific components that counteract doxorubicin-induced heart failure from Acontium carmichaeli. Anal Chem 2014; 86:4748-57. [PMID: 24731167 PMCID: PMC4033634 DOI: 10.1021/ac500287e] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
![]()
Cell membrane chromatography (CMC)
derived from pathological tissues
is ideal for screening specific components acting on specific diseases
from complex medicines owing to the maximum simulation of in vivo drug-receptor interactions. However, there are no
pathological tissue-derived CMC models that have ever been developed,
as well as no visualized affinity comparison of potential active components
between normal and pathological CMC columns. In this study, a novel
comparative normal/failing rat myocardium CMC analysis system based
on online column selection and comprehensive two-dimensional (2D)
chromatography/monolithic column/time-of-flight mass spectrometry
was developed for parallel comparison of the chromatographic behaviors
on both normal and pathological CMC columns, as well as rapid screening
of the specific therapeutic agents that counteract doxorubicin (DOX)-induced
heart failure from Acontium carmichaeli (Fuzi). In
total, 16 potential active alkaloid components with similar structures
in Fuzi were retained on both normal and failing myocardium CMC models.
Most of them had obvious decreases of affinities on failing myocardium
CMC compared with normal CMC model except for four components, talatizamine
(TALA), 14-acetyl-TALA, hetisine, and 14-benzoylneoline. One compound
TALA with the highest affinity was isolated for further in
vitro pharmacodynamic validation and target identification
to validate the screen results. Voltage-dependent K+ channel
was confirmed as a binding target of TALA and 14-acetyl-TALA with
high affinities. The online high throughput comparative CMC analysis
method is suitable for screening specific active components from herbal
medicines by increasing the specificity of screened results and can
also be applied to other biological chromatography models.
Collapse
Affiliation(s)
- Xiaofei Chen
- Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University , No. 325 Guohe Road, Shanghai 200433, PR China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
60
|
Li Y, Chen Y, Xiao C, Chen D, Xiao Y, Mei Z. Rapid screening and identification of α-amylase inhibitors from Garcinia xanthochymus using enzyme-immobilized magnetic nanoparticles coupled with HPLC and MS. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 960:166-73. [PMID: 24814002 DOI: 10.1016/j.jchromb.2014.04.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/18/2014] [Accepted: 04/22/2014] [Indexed: 12/30/2022]
Abstract
α-Amylase inhibitors play an important role in management of diabetes and obesity. In order to rapidly discover potent α-amylase inhibitors from medicinal plants, a ligands-screening method based on enzyme-immobilized magnetic nanoparticles integrated with HPLC was developed. Amine-terminated magnetic nanoparticles were prepared for the immobilization of α-amylase. Based on the affinity theory, the α-amylase-coated magnetic nanoparticles were employed to fish out the ligands from the extracts of Garcinia xanthochymus, and the elutes were examined by HPLC. As a result, three ligands were screened out. Isolation and identification were carried out subsequently. By analyzing the UV, MS and NMR spectra, they were identified as three biflavonoids including GB2a glucoside (2), GB2a (3) and fukugetin (4). The IC50 values of the three compounds were also determined. The results suggest the proposed approach is efficient and accurate, and has great potential in rapid discovery of drug candidates from medical plants.
Collapse
Affiliation(s)
- Yunfang Li
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China; College of Pharmacy, South Central University for Nationalities, Wuhan 430074, China
| | - Yu Chen
- College of Chemistry and Material Sciences, South Central University for Nationalities, Wuhan 430074, China
| | - Chuying Xiao
- College of Pharmacy, South Central University for Nationalities, Wuhan 430074, China
| | - Dan Chen
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Yuxiu Xiao
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Zhinan Mei
- College of Pharmacy, South Central University for Nationalities, Wuhan 430074, China.
| |
Collapse
|
61
|
Vanzolini KL, Jiang Z, Zhang X, Vieira LCC, Corrêa AG, Cardoso CL, Cass QB, Moaddel R. Acetylcholinesterase immobilized capillary reactors coupled to protein coated magnetic beads: a new tool for plant extract ligand screening. Talanta 2013; 116:647-52. [PMID: 24148457 PMCID: PMC3826612 DOI: 10.1016/j.talanta.2013.07.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 10/26/2022]
Abstract
The use of immobilized capillary enzyme reactors (ICERs) and enzymes coated to magnetic beads ((NT or CT)-MB) for ligand screening has been adopted as a new technique of high throughput screening (HTS). In this work the selected target was the enzyme acetylcholinesterase (AChE), which acts on the central nervous system and is a validated target for the treatment of Alzheimer's disease, as well as for new insecticides. A new approach for the screening of plant extracts was developed based on the ligand fishing experiments and zonal chromatography. For that, the magnetic beads were used for the ligand fishing experiments and capillary bioreactors for the activity assays. The latter was employed also under non-linear conditions to determine the affinity constants of known ligands, for the first time, as well as for the active fished ligand.
Collapse
Affiliation(s)
- Kenia Lourenço Vanzolini
- Departamento de Química, Universidade Federal de São Carlos, caixa postal 676, São Carlos 13565-905, Brazil
- Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD 21224, USA
| | - Zhengjin Jiang
- Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China
| | - Xiaoqi Zhang
- Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China
| | | | - Arlene Gonçalvez Corrêa
- Departamento de Química, Universidade Federal de São Carlos, caixa postal 676, São Carlos 13565-905, Brazil
| | - Carmen Lucia Cardoso
- Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901 SP, Brazil
| | - Quezia Bezerra Cass
- Departamento de Química, Universidade Federal de São Carlos, caixa postal 676, São Carlos 13565-905, Brazil
| | - Ruin Moaddel
- Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD 21224, USA
- Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China
| |
Collapse
|
62
|
Zhao X, Li Q, Huang J, Zheng J, Zheng X, Li Z, Zhang Y. EFFECTS OF TEMPERATURE AND MOBILE PHASE COMPOSITION ON THE INTERACTION BETWEEN BERBERINE AND IMMOBILIZED β2-ADRENOCEPTOR BY HIGH PERFORMANCE AFFINITY CHROMATOGRAPHY. J LIQ CHROMATOGR R T 2013. [DOI: 10.1080/10826076.2012.734001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Xinfeng Zhao
- a College of Life Sciences , Northwest University , Xi'an , China
| | - Qian Li
- a College of Life Sciences , Northwest University , Xi'an , China
| | - Jingjing Huang
- a College of Life Sciences , Northwest University , Xi'an , China
| | - Jianbin Zheng
- b Institute of Analytical Science , Northwest University , Xi'an , China
| | - Xiaohui Zheng
- a College of Life Sciences , Northwest University , Xi'an , China
| | - Zijian Li
- c Institute of Vascular Medicine, Peking University, Third Hospital and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education , Beijing , China
| | - Youyi Zhang
- c Institute of Vascular Medicine, Peking University, Third Hospital and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education , Beijing , China
| |
Collapse
|
63
|
Singh N, Ravichandran S, Norton DD, Fugmann SD, Moaddel R. Synthesis and characterization of a SIRT6 open tubular column: predicting deacetylation activity using frontal chromatography. Anal Biochem 2013; 436:78-83. [PMID: 23376017 PMCID: PMC4167792 DOI: 10.1016/j.ab.2013.01.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 01/14/2013] [Accepted: 01/18/2013] [Indexed: 02/02/2023]
Abstract
SIRT6 is a histone deacetylase that has been proposed as a potential therapeutic target for metabolic disorders and the prevention of age-associated diseases. Thus the identification of compounds that modulate SIRT6 activity could be of great therapeutic importance. We have previously reported on the identification of quercetin and vitexin as SIRT6 inhibitors, using SIRT6-coated magnetic beads. In this study, we have immobilized SIRT6 onto the surface of an open tubular capillary and characterized the quercetin binding site using frontal displacement chromatography. Structurally related flavonoids were tested for their activity on SIRT6, including apigenin, naringenin, luteolin, and kaempferol. In addition to obtaining their binding activity using frontal affinity chromatographic techniques, we also ranked the compounds based on their ability to displace quercetin. The data suggest that a single displacement curve is representative of the enzymatic activity of the tested ligand. In addition, using the inhibition data obtained in this study, we developed a preliminary pharmacophore model that confirmed the experimental data.
Collapse
Affiliation(s)
- Nagendra Singh
- Biomedical Research Center, National institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Sarangan Ravichandran
- Advanced Biomedical Computing Center, Simulation, Analysis & Mathematical Modeling Group SAIC-Frederick, Inc. Frederick National Laboratory for Cancer Research (FNLCR) P.O. Box B, Frederick, MD 21702
| | - Darrell D. Norton
- Biomedical Research Center, National institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Sebastian D. Fugmann
- Biomedical Research Center, National institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Ruin Moaddel
- Biomedical Research Center, National institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| |
Collapse
|
64
|
Immobilized magnetic beads based multi-target affinity selection coupled with high performance liquid chromatography-mass spectrometry for screening anti-diabetic compounds from a Chinese medicine "Tang-Zhi-Qing". J Pharm Biomed Anal 2013; 78-79:190-201. [PMID: 23501439 DOI: 10.1016/j.jpba.2013.02.024] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Revised: 02/16/2013] [Accepted: 02/19/2013] [Indexed: 11/21/2022]
Abstract
We developed an approach for screening bioactive compounds from botanical drug using multiple target-immobilized magnetic beads coupled with high performance liquid chromatography-mass spectrometry. This novel approach was called magnetic beads based multi-target affinity selection-mass spectrometry (MT-ASMS). It can enrich and identify different types of ligands from mixture extracts. Multiple targets (maltase, invertase, lipase) were immobilized on the magnetic beads by covalent linkage using 1-(3-dimethyl-aminopropyl)-3-ethyl-carbodiimide (EDC) and N-hydroxysuccinimide (NHS) as reaction reagents, respectively. The properties of enzyme conjugated magnetic beads were characterized using transmission electron microscopy, X-ray diffractometer and vibration sample magnetometer. Several factors including pH, ion strength, incubation time and temperature were optimized using three known ligands (caffeic acid, ferulic acid, and hesperidin). The established MT-ASMS approach was applied to screening for ligands from a Chinese medicine "Tang-Zhi-Qing", which was used to treat type II diabetes in China. Seven bound compounds were identified via liquid chromatography-mass spectrometry (LC/MS). Five active compounds including 2,3,4,6-tetra-O-galloyl-D-glucose, 1,2,3,4-tetra-O-galloyl-D-glucose, 1,2,3,4,6-penta-O-galloyl-d-glucose, quercetin-3-O-β-D-glucuronide and quercetin-3-O-β-D-glucoside were identified and their activities were validated by conventional inhibitory assay. Our findings suggested that the proposed approach is efficient in screening compounds with multiple activities from extracts of botanical drugs.
Collapse
|
65
|
Beauharnois JM, Bolívar BE, Welch JT. Sirtuin 6: a review of biological effects and potential therapeutic properties. MOLECULAR BIOSYSTEMS 2013; 9:1789-806. [DOI: 10.1039/c3mb00001j] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
66
|
Kokkonen P, Rahnasto-Rilla M, Kiviranta PH, Huhtiniemi T, Laitinen T, Poso A, Jarho E, Lahtela-Kakkonen M. Peptides and Pseudopeptides as SIRT6 Deacetylation Inhibitors. ACS Med Chem Lett 2012; 3:969-74. [PMID: 24900419 DOI: 10.1021/ml300139n] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 10/23/2012] [Indexed: 12/11/2022] Open
Abstract
SIRT6 belongs to the family of histone deacetylases (class III), but it also has mono-ADP-ribosyltransferase activity. SIRT6 is a nuclear sirtuin that has been associated with aging, cellular protection, and sugar metabolism. Despite these important roles for SIRT6, thus far, there are only a few weak SIRT6 inhibitors available, and no structure-activity relationship (SAR) studies have been published. This is the first study concerning peptides and pseudopeptides as SIRT6 deacetylation inhibitors and the first SAR data concerning SIRT6. We also investigated the molecular interactions using a homology model. We report three compounds exhibiting 62-91% SIRT6 inhibition at 200 μM concentration. These compounds can serve as starting points for systematic SAR studies and SIRT6 inhibitor design.
Collapse
Affiliation(s)
- Piia Kokkonen
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Minna Rahnasto-Rilla
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Päivi H. Kiviranta
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Tero Huhtiniemi
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Tuomo Laitinen
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Antti Poso
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Elina Jarho
- School of
Pharmacy, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | | |
Collapse
|
67
|
Okello EJ, Leylabi R, McDougall GJ. Inhibition of acetylcholinesterase by green and white tea and their simulated intestinal metabolites. Food Funct 2012; 3:651-61. [PMID: 22418730 DOI: 10.1039/c2fo10174b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By 2034 it is forecast that 5% of the global population will be aged 85 years or over--approximately two and half fold increase on present day figures--which will inevitably lead to an increase in age-associated disorders such as Alzheimer's disease. There is mounting evidence that green tea (Camellia sinensis) possesses numerous health-promoting properties, and may potentially be beneficial to those suffering from Alzheimer's and other diseases, including cardiovascular disease and cancer. These beneficial properties are largely attributed to the high polyphenol content, particularly the catechins. In this study, we measured acetylcholinesterase inhibition by white and green teas and their simulated intestinal digests. We found that the potency with which the white and green tea extracts inhibited acetylcholinesterase varied through the simulated digestion procedure. Initially, in the undigested extract form, potency was high with IC₅₀ values of 7.20 μg mL⁻¹ and 8.06 μg mL⁻¹ for green and white tea respectively.However, this decreased significantly after gastric digestion but activity was recovered after pancreatic digestion which could be related to relative increases in the levels of caffeine and specific phenolic components. Of the pure tea compounds tested, EGCG was the most potent with an IC₅₀ of 0.0096 μmol mL⁻¹ but its breakdown product; γ-valerolactone was the least potent analyte. Particularly interesting were the results of caffeine,which exhibited a strong inhibitory activity and pyrogallol, which recorded a much stronger potency than its parent compound gallic acid, suggesting a pro-drug-like relationship. Overall, the results indicate that further research is necessary to determine the full potential of digestion of tea and its metabolites and how inter-individual variation may indicate that some sections of society could potentially benefit more from drinking tea as a strategy to prevent the development of dementia. We have also shown the activities of a number of metabolites,however, further research is required to determine their potential bioavailability.
Collapse
Affiliation(s)
- Edward J Okello
- Medicinal Plant Research Group, School of Agriculture, Food and Rural Development, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom.
| | | | | |
Collapse
|
68
|
Zhao X, Li Q, Bian L, Zheng X, Zheng J, Zhang Y, Li Z. Using immobilized G-protein coupled receptors to screen bioactive traditional Chinese medicine compounds with multiple targets. J Pharm Biomed Anal 2012; 70:549-52. [PMID: 22651959 DOI: 10.1016/j.jpba.2012.05.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 04/25/2012] [Accepted: 05/05/2012] [Indexed: 10/28/2022]
Abstract
Demand on high-throughput methods for multi-target compounds screening continues to increase nowadays due to the decline of new drugs on the market. Two kinds of G-protein-coupled receptors, alpha1-adrenoceptor (α(1A)-AR) and beta2-adrenoceptor (β(2)-AR), were purified and immobilized on the surface of macroporous silica gel to prepare new chromatographic stationary phases. Control drugs (e.g., prazosin, terazosin, salbutamol, and terbutaline) were used to characterize the retention behavior of the obtained α(1A)-AR and β(2)-AR columns. This study also coupled both columns with a six-way switching valve to construct an automatic two-dimensional system for multi-target compounds screening in complex mixtures. Adrenaline hydrochloride was used as a representative drug to evaluate the chromatographic performance of the two dimensional system. The aqueous extracts from Salvia miltiorrhiza and Coptis chinensis were also analyzed by the automatic system. The compounds in S. miltiorrhiza had no binding to both α(1A)-AR and β(2)-AR columns. But berberine, palmatine and jatrorrhizine were screened as the bioactive compounds in C. chinensis, targeting both the receptors. The proposed method is an alternative for recognizing and separating the compounds targeting different proteins from a complex matrix.
Collapse
Affiliation(s)
- Xinfeng Zhao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Northwest University, Xi'an 710069, China
| | | | | | | | | | | | | |
Collapse
|
69
|
Ji L, Wu JH, Luo Q, Li X, Zheng W, Zhai G, Wang F, Lü S, Feng YQ, Liu J, Xiong S. Quantitative mass spectrometry combined with separation and enrichment of phosphopeptides by titania coated magnetic mesoporous silica microspheres for screening of protein kinase inhibitors. Anal Chem 2012; 84:2284-91. [PMID: 22304342 DOI: 10.1021/ac202897u] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We describe herein the development of a matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) approach for screening of protein kinase inhibitors (PKIs). MS quantification of phosphopeptides, the kinase-catalyzed products of nonphosphorylated substrates, is a great challenge due to the ion suppression effect of highly abundant nonphosphorylated peptides in enzymatic reaction mixtures. To address this issue, a novel type of titania coated magnetic hollow mesoporous silica spheres (TiO(2)/MHMSS) material was fabricated for capturing phosphopeptides from the enzymatic reaction mixtures prior to MS analysis. Under optimized conditions, even in the presence of 1000-fold of a substrate peptide of tyrosine kinase epidermal growth factor receptor (EGFR), the phosphorylated substrates at the femtomole level can be detected with high accuracy and reproducibility. With a synthetic nonisotopic labeled phosphopeptide, of which the sequence is similar to that of the phosphorylated substrate, as the internal standard, the MS signal ratio of the phosphorylated substrate to the standard is linearly correlated with the molar ratio of the two phosphopeptides in peptide mixtures over the range of 0.1 to 4 with r(2) being 0.99. The IC(50) values of three EGFR inhibitors synthesized in our laboratory were then determined, and the results are consistent with those determined by an enzyme-linked immunosorbent assay (ELISA). The developed method is sensitive, cost/time-effective, and operationally simple and does not require isotope/radioative-labeling, providing an ideal alterative for screening of PKIs as therapeutic agents.
Collapse
Affiliation(s)
- Liyun Ji
- Beijing National Laboratory for Molecular Sciences, Beijing Centre for Mass Spectrometry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|