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Palermo G, Schouten WM, Alonso LL, Ulens C, Kool J, Slagboom J. Acetylcholine-Binding Protein Affinity Profiling of Neurotoxins in Snake Venoms with Parallel Toxin Identification. Int J Mol Sci 2023; 24:16769. [PMID: 38069093 PMCID: PMC10706727 DOI: 10.3390/ijms242316769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 11/23/2023] [Accepted: 11/24/2023] [Indexed: 12/18/2023] Open
Abstract
Snakebite is considered a concerning issue and a neglected tropical disease. Three-finger toxins (3FTxs) in snake venoms primarily cause neurotoxic effects since they have high affinity for nicotinic acetylcholine receptors (nAChRs). Their small molecular size makes 3FTxs weakly immunogenic and therefore not appropriately targeted by current antivenoms. This study aims at presenting and applying an analytical method for investigating the therapeutic potential of the acetylcholine-binding protein (AChBP), an efficient nAChR mimic that can capture 3FTxs, for alternative treatment of elapid snakebites. In this analytical methodology, snake venom toxins were separated and characterised using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) and high-throughput venomics. By subsequent nanofractionation analytics, binding profiling of toxins to the AChBP was achieved with a post-column plate reader-based fluorescence-enhancement ligand displacement bioassay. The integrated method was established and applied to profiling venoms of six elapid snakes (Naja mossambica, Ophiophagus hannah, Dendroaspis polylepis, Naja kaouthia, Naja haje and Bungarus multicinctus). The methodology demonstrated that the AChBP is able to effectively bind long-chain 3FTxs with relatively high affinity, but has low or no binding affinity towards short-chain 3FTxs, and as such provides an efficient analytical platform to investigate binding affinity of 3FTxs to the AChBP and mutants thereof and to rapidly identify bound toxins.
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Affiliation(s)
- Giulia Palermo
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Wietse M. Schouten
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Luis Lago Alonso
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Chris Ulens
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, 3000 Leuven, Belgium;
| | - Jeroen Kool
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Julien Slagboom
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
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Kazandjian TD, Arrahman A, Still KBM, Somsen GW, Vonk FJ, Casewell NR, Wilkinson MC, Kool J. Anticoagulant Activity of Naja nigricollis Venom Is Mediated by Phospholipase A2 Toxins and Inhibited by Varespladib. Toxins (Basel) 2021; 13:toxins13050302. [PMID: 33922825 PMCID: PMC8145175 DOI: 10.3390/toxins13050302] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/07/2021] [Accepted: 04/18/2021] [Indexed: 12/03/2022] Open
Abstract
Bites from elapid snakes typically result in neurotoxic symptoms in snakebite victims. Neurotoxins are, therefore, often the focus of research relating to understanding the pathogenesis of elapid bites. However, recent evidence suggests that some elapid snake venoms contain anticoagulant toxins which may help neurotoxic components spread more rapidly. This study examines the effects of venom from the West African black-necked spitting cobra (Naja nigricollis) on blood coagulation and identifies potential coagulopathic toxins. An integrated RPLC-MS methodology, coupled with nanofractionation, was first used to separate venom components, followed by MS, proteomics and coagulopathic bioassays. Coagulation assays were performed on both crude and nanofractionated N. nigricollis venom toxins as well as PLA2s and 3FTx purified from the venom. Assays were then repeated with the addition of either the phospholipase A2 inhibitor varespladib or the snake venom metalloproteinase inhibitor marimastat to assess whether either toxin inhibitor is capable of neutralizing coagulopathic venom activity. Subsequent proteomic analysis was performed on nanofractionated bioactive venom toxins using tryptic digestion followed by nanoLC-MS/MS measurements, which were then identified using Swiss-Prot and species-specific database searches. Varespladib, but not marimastat, was found to significantly reduce the anticoagulant activity of N. nigricollis venom and MS and proteomics analyses confirmed that the anticoagulant venom components mostly consisted of PLA2 proteins. We, therefore, conclude that PLA2s are the most likely candidates responsible for anticoagulant effects stimulated by N. nigricollis venom.
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Affiliation(s)
- Taline D. Kazandjian
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (T.D.K.); (N.R.C.)
| | - Arif Arrahman
- Department of Chemistry and Pharmaceutical Sciences, Division of Bioanalytical Chemistry, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081HV Amsterdam, The Netherlands; (A.A.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1012WX Amsterdam, The Netherlands
- Faculty of Pharmacy, Kampus Baru UI, Universitas Indonesia, Depok 16424, Indonesia
| | - Kristina B. M. Still
- Department of Chemistry and Pharmaceutical Sciences, Division of Bioanalytical Chemistry, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081HV Amsterdam, The Netherlands; (A.A.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1012WX Amsterdam, The Netherlands
| | - Govert W. Somsen
- Department of Chemistry and Pharmaceutical Sciences, Division of Bioanalytical Chemistry, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081HV Amsterdam, The Netherlands; (A.A.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1012WX Amsterdam, The Netherlands
| | - Freek J. Vonk
- Naturalis Biodiversity Center, Darwinweg 2, 2333CR Leiden, The Netherlands;
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (T.D.K.); (N.R.C.)
| | - Mark C. Wilkinson
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (T.D.K.); (N.R.C.)
- Correspondence: (M.C.W.); (J.K.)
| | - Jeroen Kool
- Department of Chemistry and Pharmaceutical Sciences, Division of Bioanalytical Chemistry, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081HV Amsterdam, The Netherlands; (A.A.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1012WX Amsterdam, The Netherlands
- Correspondence: (M.C.W.); (J.K.)
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Xie C, Albulescu LO, Bittenbinder MA, Somsen GW, Vonk FJ, Casewell NR, Kool J. Neutralizing Effects of Small Molecule Inhibitors and Metal Chelators on Coagulopathic Viperinae Snake Venom Toxins. Biomedicines 2020; 8:E297. [PMID: 32825484 PMCID: PMC7555180 DOI: 10.3390/biomedicines8090297] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/13/2020] [Accepted: 08/18/2020] [Indexed: 12/27/2022] Open
Abstract
Animal-derived antivenoms are the only specific therapies currently available for the treatment of snake envenoming, but these products have a number of limitations associated with their efficacy, safety and affordability for use in tropical snakebite victims. Small molecule drugs and drug candidates are regarded as promising alternatives for filling the critical therapeutic gap between snake envenoming and effective treatment. In this study, by using an advanced analytical technique that combines chromatography, mass spectrometry and bioassaying, we investigated the effect of several small molecule inhibitors that target phospholipase A2 (varespladib) and snake venom metalloproteinase (marimastat, dimercaprol and DMPS) toxin families on inhibiting the activities of coagulopathic toxins found in Viperinae snake venoms. The venoms of Echis carinatus, Echis ocellatus, Daboia russelii and Bitis arietans, which are known for their potent haemotoxicities, were fractionated in high resolution onto 384-well plates using liquid chromatography followed by coagulopathic bioassaying of the obtained fractions. Bioassay activities were correlated to parallel recorded mass spectrometric and proteomics data to assign the venom toxins responsible for coagulopathic activity and assess which of these toxins could be neutralized by the inhibitors under investigation. Our results showed that the phospholipase A2-inhibitor varespladib neutralized the vast majority of anticoagulation activities found across all of the tested snake venoms. Of the snake venom metalloproteinase inhibitors, marimastat demonstrated impressive neutralization of the procoagulation activities detected in all of the tested venoms, whereas dimercaprol and DMPS could only partially neutralize these activities at the doses tested. Our results provide additional support for the concept that combinations of small molecules, particularly the combination of varespladib with marimastat, serve as a drug-repurposing opportunity to develop new broad-spectrum inhibitor-based therapies for snakebite envenoming.
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Affiliation(s)
- Chunfang Xie
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Laura-Oana Albulescu
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (L.-O.A.); (N.R.C.)
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Mátyás A. Bittenbinder
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
- Naturalis Biodiversity Center, 2333 CR Leiden, The Netherlands
| | - Govert W. Somsen
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Freek J. Vonk
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (L.-O.A.); (N.R.C.)
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Jeroen Kool
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
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Xie C, Albulescu LO, Still KBM, Slagboom J, Zhao Y, Jiang Z, Somsen GW, Vonk FJ, Casewell NR, Kool J. Varespladib Inhibits the Phospholipase A 2 and Coagulopathic Activities of Venom Components from Hemotoxic Snakes. Biomedicines 2020; 8:E165. [PMID: 32560391 DOI: 10.3390/biomedicines8060165] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/04/2020] [Accepted: 06/11/2020] [Indexed: 11/17/2022] Open
Abstract
Phospholipase A2 (PLA2) enzymes are important toxins found in many snake venoms, and they can exhibit a variety of toxic activities including causing hemolysis and/or anticoagulation. In this study, the inhibiting effects of the small molecule PLA2 inhibitor varespladib on snake venom PLA2s was investigated by nanofractionation analytics, which combined chromatography, mass spectrometry (MS), and bioassays. The venoms of the medically important snake species Bothrops asper, Calloselasma rhodostoma, Deinagkistrodon acutus, Daboia russelii, Echis carinatus, Echis ocellatus, and Oxyuranus scutellatus were separated by liquid chromatography (LC) followed by nanofractionation and interrogation of the fractions by a coagulation assay and a PLA2 assay. Next, we assessed the ability of varespladib to inhibit the activity of enzymatic PLA2s and the coagulopathic toxicities induced by fractionated snake venom toxins, and identified these bioactive venom toxins and those inhibited by varespladib by using parallel recorded LC-MS data and proteomics analysis. We demonstrated here that varespladib was not only capable of inhibiting the PLA2 activities of hemotoxic snake venoms, but can also effectively neutralize the coagulopathic toxicities (most profoundly anticoagulation) induced by venom toxins. While varespladib effectively inhibited PLA2 toxins responsible for anticoagulant effects, we also found some evidence that this inhibitory molecule can partially abrogate procoagulant venom effects caused by different toxin families. These findings further emphasize the potential clinical utility of varespladib in mitigating the toxic effects of certain snakebites.
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Xie C, Slagboom J, Albulescu LO, Bruyneel B, Still KBM, Vonk FJ, Somsen GW, Casewell NR, Kool J. Antivenom Neutralization of Coagulopathic Snake Venom Toxins Assessed by Bioactivity Profiling Using Nanofractionation Analytics. Toxins (Basel) 2020; 12:E53. [PMID: 31963329 PMCID: PMC7020444 DOI: 10.3390/toxins12010053] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 12/21/2022] Open
Abstract
Venomous snakebite is one of the world's most lethal neglected tropical diseases. Animal-derived antivenoms are the only standardized specific therapies currently available for treating snakebite envenoming, but due to venom variation, often this treatment is not effective in counteracting all clinical symptoms caused by the multitude of injected toxins. In this study, the coagulopathic toxicities of venoms from the medically relevant snake species Bothropsasper, Calloselasmarhodostoma, Deinagkistrodonacutus, Daboiarusselii, Echiscarinatus and Echisocellatus were assessed. The venoms were separated by liquid chromatography (LC) followed by nanofractionation and parallel mass spectrometry (MS). A recently developed high-throughput coagulation assay was employed to assess both the pro- and anticoagulant activity of separated venom toxins. The neutralization capacity of antivenoms on separated venom components was assessed and the coagulopathic venom peptides and enzymes that were either neutralized or remained active in the presence of antivenom were identified by correlating bioassay results with the MS data and with off-line generated proteomics data. The results showed that most snake venoms analyzed contained both procoagulants and anticoagulants. Most anticoagulants were identified as phospholipases A2s (PLA2s) and most procoagulants correlated with snake venom metalloproteinases (SVMPs) and serine proteases (SVSPs). This information can be used to better understand antivenom neutralization and can aid in the development of next-generation antivenom treatments.
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Affiliation(s)
- Chunfang Xie
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; (C.X.); (J.S.); (B.B.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Julien Slagboom
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; (C.X.); (J.S.); (B.B.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Laura-Oana Albulescu
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK (N.R.C.)
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Ben Bruyneel
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; (C.X.); (J.S.); (B.B.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Kristina B. M. Still
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; (C.X.); (J.S.); (B.B.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Freek J. Vonk
- Naturalis Biodiversity Center, 2333 CR Leiden, The Netherlands;
| | - Govert W. Somsen
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; (C.X.); (J.S.); (B.B.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK (N.R.C.)
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Jeroen Kool
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; (C.X.); (J.S.); (B.B.); (K.B.M.S.); (G.W.S.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
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Zietek BM, Mladic M, Bruyneel B, Niessen WMA, Honing M, Somsen GW, Kool J. Nanofractionation Platform with Parallel Mass Spectrometry for Identification of CYP1A2 Inhibitors in Metabolic Mixtures. SLAS Discov 2017; 23:283-293. [PMID: 29262760 DOI: 10.1177/2472555217746323] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
With early assessment of inhibitory properties of drug candidates and their circulating metabolites toward cytochrome P450 enzymes, drug attrition, especially later in the drug development process, can be decreased. Here we describe the development and validation of an at-line nanofractionation platform, which was applied for screening of CYP1A2 inhibitors in Phase I metabolic mixtures. With this platform, a metabolic mixture is separated by liquid chromatography (LC), followed by parallel nanofractionation on a microtiter well plate and mass spectrometry (MS) analysis. After solvent evaporation, all metabolites present in the nanofractionated mixture are assayed utilizing a fluorescence CYP1A2 inhibition bioassay performed on the plate. Next, a bioactivity chromatogram is constructed from the bioassay results. By peak shape and retention time correlation of the bioactivity peaks with the obtained MS data, CYP1A2-bioactive inhibiting metabolites can be identified. The method correctly evaluated the potency of five CYP1A2 inhibitors. Mixtures comprising potent inhibitors of CYP1A2 or in vitro-generated metabolites of ellipticine were evaluated for their inhibitory bioactivities. In both cases, good LC separation of all compounds was achieved and bioactivity data could be accurately correlated with the parallel recorded MS data. Generation and evaluation of Phase II metabolites of hydroxylated ellipticine was also pursued.
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Affiliation(s)
- Barbara M Zietek
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Marija Mladic
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Ben Bruyneel
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Wilfried M A Niessen
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,3 hyphen MassSpec, Voorhout, Netherlands
| | - Maarten Honing
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,2 DSM Materials Science Center, Geleen, Netherlands
| | - Govert W Somsen
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Jeroen Kool
- 1 Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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