1
|
Sun MZ, Lyu LS, Zheng QC. How does multiple substrate binding lead to substrate inhibition of CYP2D6 metabolizing dextromethorphan? A theoretical study. Phys Chem Chem Phys 2023; 25:5164-5173. [PMID: 36723118 DOI: 10.1039/d2cp05634h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
CYP2D6 is one of the most important metalloenzymes involved in the biodegradation of many drug molecules in the human body. It has been found that multiple substrate binding can lead to substrate inhibition of CYP2D6 metabolizing dextromethorphan (DM), but the corresponding theoretical mechanism is rarely reported. Therefore, we chose DM as the probe and performed molecular dynamics simulations and quantum mechanical calculations on CYP2D6-DM systems to investigate the mechanism of how the multiple substrate binding leads to the substrate inhibition of CYP2D6 metabolizing substrates. According to our results, three gate residues (Arg221, Val374, and Phe483) for the catalytic pocket are determined. We also found that the multiple substrate binding can lead to substrate inhibition by reducing the stability of CYP2D6 binding DM and increasing the reactive activation energy of the rate-determining step. Our findings would help to understand the substrate inhibition of CYP2D6 metabolizing the DM and enrich the knowledge of the drug-drug interactions for the cytochrome P450 superfamily.
Collapse
Affiliation(s)
- Min-Zhang Sun
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun, 130023, China
| | - Ling-Shan Lyu
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun, 130023, China
| | - Qing-Chuan Zheng
- School of Pharmaceutical Sciences, Jilin University, Changchun, 130023, China. .,Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun, 130023, China
| |
Collapse
|
2
|
van Vugt-Lussenburg BMA, Capinha L, Reinen J, Rooseboom M, Kranendonk M, Onderwater RCA, Jennings P. " Commandeuring" Xenobiotic Metabolism: Advances in Understanding Xenobiotic Metabolism. Chem Res Toxicol 2022; 35:1184-1201. [PMID: 35768066 PMCID: PMC9297329 DOI: 10.1021/acs.chemrestox.2c00067] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The understanding
of how exogenous chemicals (xenobiotics) are
metabolized, distributed, and eliminated is critical to determine
the impact of the chemical and its metabolites to the (human) organism.
This is part of the research and educational discipline ADMET (absorption,
distribution, metabolism, elimination, and toxicity). Here, we review
the work of Jan Commandeur and colleagues who have not only made a
significant impact in understanding of phase I and phase II metabolism
of several important compounds but also contributed greatly to the
development of experimental techniques for the study of xenobiotic
metabolism. Jan Commandeur’s work has covered a broad area
of research, such as the development of online screening methodologies,
the use of a combination of enzyme mutagenesis and molecular modeling
for structure–activity relationship (SAR) studies, and the
development of novel probe substrates. This work is the bedrock of
current activities and brings the field closer to personalized (cohort-based)
pharmacology, toxicology, and hazard/risk assessment.
Collapse
Affiliation(s)
| | - Liliana Capinha
- Division of Computational and Molecular Toxicology, Department of Chemistry and Pharmaceutical Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMs), Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Jelle Reinen
- Charles River Den Bosch, Hambakenwetering 7, 5203 DL Hertogenbosch, The Netherlands
| | - Martijn Rooseboom
- Shell Global Solutions International B.V., 1030 BN The Hague, The Netherlands
| | - Michel Kranendonk
- Center for Toxicogenomics and Human Health (ToxOmics), NOVA Medical School/Faculty of Medical Sciences, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria 130, 1169-056 Lisboa, Portugal
| | | | - Paul Jennings
- Division of Computational and Molecular Toxicology, Department of Chemistry and Pharmaceutical Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMs), Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| |
Collapse
|
3
|
Glass SM, Martell CM, Oswalt AK, Osorio-Vasquez V, Cho C, Hicks MJ, Mills JM, Fujiwara R, Glista MJ, Kamath SS, Furge LL. CYP2D6 Allelic Variants *34, *17-2, *17-3, and *53 and a Thr309Ala Mutant Display Altered Kinetics and NADPH Coupling in Metabolism of Bufuralol and Dextromethorphan and Altered Susceptibility to Inactivation by SCH 66712. Drug Metab Dispos 2018; 46:1106-1117. [PMID: 29784728 PMCID: PMC6038030 DOI: 10.1124/dmd.117.079871] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 05/09/2018] [Indexed: 01/27/2023] Open
Abstract
Metabolic phenotype can be affected by multiple factors, including allelic variation and interactions with inhibitors. Human CYP2D6 is responsible for approximately 20% of cytochrome P450-mediated drug metabolism but consists of more than 100 known variants; several variants are commonly found in the population, whereas others are quite rare. Four CYP2D6 allelic variants-three with a series of mutations distal to the active site (*34, *17-2, *17-3) and one ultra-metabolizer with mutations near the active site (*53), along with reference *1 and an active site mutant of *1 (Thr309Ala)-were expressed, purified, and studied for interactions with the typical substrates dextromethorphan and bufuralol and the inactivator SCH 66712. We found that *34, *17-2, and *17-3 displayed reduced enzyme activity and NADPH coupling while producing the same metabolites as *1, suggesting a possible role for Arg296 in NADPH coupling. A higher-activity variant, *53, displayed similar NADPH coupling to *1 but was less susceptible to inactivation by SCH 66712. The Thr309Ala mutant showed similar activity to that of *1 but with greatly reduced NADPH coupling. Overall, these results suggest that kinetic and metabolic analysis of individual CYP2D6 variants is required to understand their possible contributions to variable drug response and the complexity of personalized medicine.
Collapse
Affiliation(s)
- Sarah M Glass
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan
| | | | | | | | - Christi Cho
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan
| | - Michael J Hicks
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan
| | | | - Rina Fujiwara
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan
| | | | - Sharat S Kamath
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan
| | | |
Collapse
|
4
|
Asai Y, Sakakibara Y, Inoue R, Inoue R, Nadai M, Katoh M. Effect of single-walled carbon nanotubes on cytochrome P450 activity in human liver microsomes in vitro. Biopharm Drug Dispos 2018; 39:275-279. [PMID: 29719052 DOI: 10.1002/bdd.2133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/22/2018] [Accepted: 03/28/2018] [Indexed: 11/06/2022]
Abstract
Single-walled carbon nanotubes (SWCNTs) are made from a rolled single sheet of graphene with a diameter in the nanometer range. SWCNTs are potential carriers for drug delivery systems because antibodies or drugs can be loaded on their surface; however, their effect on the activities of cytochrome P450 (CYP) remains unclear. The aim of this study was to investigate the effect of two kinds of SWCNTs with different lengths (FH-P- and SO-SWCNTs) on human CYP activity. In addition, other nano-sized carbon materials, such as carbon black, fullerene-C60 , and fullerene-C70 were also evaluated to compare their effects on CYP activities. Ten CYP substrates (phenacetin, coumarin, bupropion, paclitaxel, tolbutamide, S-mephenytoin, dextromethorphan, chlorzoxazone, midazolam, and testosterone) were used. Testosterone 6β-hydroxylation and midazolam 1'-hydroxylation, which are catalysed by both CYP3A4 and CYP3A5 in liver microsomes, were decreased by 25% and 45%, respectively, in the presence of 0.1 mg/ml SO-SWCNT. Dextromethorphan O-demethylation, which is catalysed mainly by CYP2D6, was decreased by 40% in the presence of SO-SWCNT. Other CYP activities, however, were not attenuated by SO-SWCNT. FH-P-SWCNT, carbon black, fullerene-C60 , and fullerene-C70 at 0.1 mg/ml had no effect on CYP activities. The Ki values for testosterone 6β-hydroxylation, midazolam 1'-hydroxylation, and dextromethorphan O-demethylation in liver microsomes were 136, 34, and 56 μg/ml, respectively. SO-SWCNT was determined to be a competitive inhibitor of CYP3A4, CYP3A5, and CYP2D6. These results suggest that the effect of SO-SWCNT differs among CYP isoforms, and that the inhibition potency depends on the physicochemical properties of the nanocarbons.
Collapse
Affiliation(s)
- Yuki Asai
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, 468-8503, Japan
| | - Yukiko Sakakibara
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, 468-8503, Japan
| | - Rina Inoue
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, 468-8503, Japan
| | - Rikako Inoue
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, 468-8503, Japan
| | - Masayuki Nadai
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, 468-8503, Japan
| | - Miki Katoh
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, 468-8503, Japan
| |
Collapse
|
5
|
Mak PJ, Denisov IG. Spectroscopic studies of the cytochrome P450 reaction mechanisms. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2018; 1866:178-204. [PMID: 28668640 PMCID: PMC5709052 DOI: 10.1016/j.bbapap.2017.06.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 06/22/2017] [Indexed: 10/19/2022]
Abstract
The cytochrome P450 monooxygenases (P450s) are thiolate heme proteins that can, often under physiological conditions, catalyze many distinct oxidative transformations on a wide variety of molecules, including relatively simple alkanes or fatty acids, as well as more complex compounds such as steroids and exogenous pollutants. They perform such impressive chemistry utilizing a sophisticated catalytic cycle that involves a series of consecutive chemical transformations of heme prosthetic group. Each of these steps provides a unique spectral signature that reflects changes in oxidation or spin states, deformation of the porphyrin ring or alteration of dioxygen moieties. For a long time, the focus of cytochrome P450 research was to understand the underlying reaction mechanism of each enzymatic step, with the biggest challenge being identification and characterization of the powerful oxidizing intermediates. Spectroscopic methods, such as electronic absorption (UV-Vis), electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), electron nuclear double resonance (ENDOR), Mössbauer, X-ray absorption (XAS), and resonance Raman (rR), have been useful tools in providing multifaceted and detailed mechanistic insights into the biophysics and biochemistry of these fascinating enzymes. The combination of spectroscopic techniques with novel approaches, such as cryoreduction and Nanodisc technology, allowed for generation, trapping and characterizing long sought transient intermediates, a task that has been difficult to achieve using other methods. Results obtained from the UV-Vis, rR and EPR spectroscopies are the main focus of this review, while the remaining spectroscopic techniques are briefly summarized. This article is part of a Special Issue entitled: Cytochrome P450 biodiversity and biotechnology, edited by Erika Plettner, Gianfranco Gilardi, Luet Wong, Vlada Urlacher, Jared Goldstone.
Collapse
Affiliation(s)
- Piotr J Mak
- Department of Chemistry, Saint Louis University, St. Louis, MO, United States.
| | - Ilia G Denisov
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, IL, United States.
| |
Collapse
|
6
|
Hu XX, Zhou Q, Lan T, Huang XX, Liang BQ, Dai DP, Cai JP, Hu GX. Functional characterization of 22 novel CYP2D6 variants for the metabolism of Tamoxifen. ACTA ACUST UNITED AC 2016; 68:819-25. [PMID: 27109434 DOI: 10.1111/jphp.12556] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/13/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVES This study aimed to assess the catalytic characteristics of 24 CYP2D6 allelic isoforms found in Chinese Han population on the metabolism of tamoxifen in vitro. METHODS Recombinant CYP2D6 microsomes of distinguished genotypes were used to characterize the corresponding enzyme activity towards tamoxifen. About 5-2500 μm tamoxifen was incubated for 30 min at 37 °C. Using high-performance liquid chromatography to detect the products, the kinetic parameters Km , Vmax and intrinsic clearance (Vmax /Km ) of N-desmethyltamoxifen were determined. KEY FINDINGS Of the 24 tested allelic variants, the differences of intrinsic clearance value were shown as follows: CYP2D6.89 was much higher than wild-type CYP2D6.1, 2 allelic isoforms (CYP2D6.88 and D336N) exhibited similar intrinsic clearance values as the wild-type enzyme, two variants displayed weak or no activity, while the rest 19 variants showed significantly reduced intrinsic clearance values ranging from 7.46 to 81.11%. CONCLUSION The comprehensive assessment of CYP2D6 variants provides significant insights into allele-specific activity towards tamoxifen in vitro, suggesting that most of the carriers of these alleles might be paid more attention when using CYP2D6-mediated drugs clinically.
Collapse
Affiliation(s)
- Xiao-Xia Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Quan Zhou
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Tian Lan
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiang-Xin Huang
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Bing-Qing Liang
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics Ministry of Health, Beijing, China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics Ministry of Health, Beijing, China
| | - Guo-Xin Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| |
Collapse
|
7
|
Millo D, Bonifacio A, Moncelli MR, Sergo V, Gooijer C, van der Zwan G. Characterization of hybrid bilayer membranes on silver electrodes as biocompatible SERS substrates to study membrane–protein interactions. Colloids Surf B Biointerfaces 2010; 81:212-6. [DOI: 10.1016/j.colsurfb.2010.07.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 04/07/2010] [Accepted: 07/06/2010] [Indexed: 11/24/2022]
|
8
|
Isin EM, Guengerich FP. Substrate binding to cytochromes P450. Anal Bioanal Chem 2008; 392:1019-30. [PMID: 18622598 DOI: 10.1007/s00216-008-2244-0] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Revised: 06/10/2008] [Accepted: 06/11/2008] [Indexed: 01/08/2023]
Abstract
P450s have attracted tremendous attention owing to not only their involvement in the metabolism of drug molecules and endogenous substrates but also the unusual nature of the reaction they catalyze, namely, the oxidation of unactivated C-H bonds. The binding of substrates to P450s, which is usually viewed as the first step in the catalytic cycle, has been studied extensively via a variety of biochemical and biophysical approaches. These studies were directed towards answering different questions related to P450s, including mechanism of oxidation, substrate properties, unusual substrate oxidation kinetics, function, and active-site features. Some of the substrate binding studies extending over a period of more than 40 years of dedicated work have been summarized in this review and categorized by the techniques employed in the binding studies.
Collapse
Affiliation(s)
- Emre M Isin
- Biotransformation Section, Department of Discovery DMPK & Bioanalytical Chemistry, AstraZeneca R & D Mölndal, 431 83, Mölndal, Sweden.
| | | |
Collapse
|
9
|
Mak PJ, Im SC, Zhang H, Waskell LA, Kincaid JR. Resonance Raman studies of cytochrome P450 2B4 in its interactions with substrates and redox partners. Biochemistry 2008; 47:3950-63. [PMID: 18311926 DOI: 10.1021/bi800034b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Resonance Raman studies of P450 2B4 are reported for the substrate-free form and when bound to the substrates, benzphetamine (BZ) or butylated hydroxytoluene (BHT), the latter representing a substrate capable of inducing an especially effective conversion to the high-spin state. In addition to studies of the ferric resting state, spectra are acquired for the ferrous CO ligated form. Importantly, for the first time, the RR technique is effectively applied to interrogate the changes in active site structure induced by binding of cytochrome P450 reductase (CPR) and Mn(III) cytochrome b 5 (Mn cyt b 5); the manganese derivative of cyt b 5 was employed to avoid spectroscopic interferences. The results, consistent with early work on mammalian P450s, demonstrate that substrate structure has minimal effects on heme structure or the FeCO fragment of the ferrous CO derivatives. Similarly, the data indicate that the protein is flexible and that substrate binding does not exert significant strain on the heme peripheral groups, in contrast to P450 cam, where substantial effects on heme peripheral groups are seen. However, significant differences are observed in the RR spectra of P450 2B4 when bound with the different redox partners, indicating that the heme structure is clearly sensitive to perturbations near the proximal heme binding site. The most substantial changes are displacements of the peripheral vinyl groups toward planarity with the heme macrocycle by cyt b 5 but away from planarity by CPR. These changes can have an impact on heme reduction potential. Most interestingly, these RR results support an earlier observation that the combination of benzphetamine and cyt b 5 binding produce a synergy leading to unique active site structural changes when both are bound.
Collapse
Affiliation(s)
- Piotr J Mak
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53233, USA
| | | | | | | | | |
Collapse
|
10
|
Bonifacio A, Millo D, Keizers PHJ, Boegschoten R, Commandeur JNM, Vermeulen NPE, Gooijer C, van der Zwan G. Active-site structure, binding and redox activity of the heme-thiolate enzyme CYP2D6 immobilized on coated Ag electrodes: a surface-enhanced resonance Raman scattering study. J Biol Inorg Chem 2008; 13:85-96. [PMID: 17899220 PMCID: PMC2099460 DOI: 10.1007/s00775-007-0303-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Accepted: 09/08/2007] [Indexed: 11/28/2022]
Abstract
Surface-enhance resonance Raman scattering spectra of the heme-thiolate enzyme cytochrome P450 2D6 (CYP2D6) adsorbed on Ag electrodes coated with 11-mercaptoundecanoic acid (MUA) were obtained in various experimental conditions. An analysis of these spectra, and a comparison between them and the RR spectra of CYP2D6 in solution, indicated that the enzyme's active site retained its nature of six-coordinated low-spin heme upon immobilization. Moreover, the spectral changes detected in the presence of dextromethorphan (a CYP2D6 substrate) and imidazole (an exogenous heme axial ligand) indicated that the immobilized enzyme also preserved its ability to reversibly bind a substrate and form a heme-imidazole complex. The reversibility of these processes could be easily verified by flowing alternately solutions of the various compounds and the buffer through a home-built spectroelectrochemical flow cell which contained a sample of immobilized protein, without the need to disassemble the cell between consecutive spectral data acquisitions. Despite immobilized CYP2D6 being effectively reduced by a sodium dithionite solution, electrochemical reduction via the Ag electrode was not able to completely reduce the enzyme, and led to its extensive inactivation. This behavior indicated that although the enzyme's ability to exchange electrons is not altered by immobilization per se, MUA-coated electrodes are not suited to perform direct electrochemistry of CYP2D6.
Collapse
Affiliation(s)
- Alois Bonifacio
- Analytical Chemistry and Applied Spectroscopy, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Diego Millo
- Analytical Chemistry and Applied Spectroscopy, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Peter H. J. Keizers
- Molecular Toxicology, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Roald Boegschoten
- Mechanical Workshop, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Jan N. M. Commandeur
- Molecular Toxicology, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Nico P. E. Vermeulen
- Molecular Toxicology, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Cees Gooijer
- Analytical Chemistry and Applied Spectroscopy, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| | - Gert van der Zwan
- Analytical Chemistry and Applied Spectroscopy, Vrije Universiteit Amsterdam, De Boelelaan 1083a, 1081 HV Amsterdam, The Netherlands
| |
Collapse
|
11
|
Hellum BH, Nilsen OG. The in vitro Inhibitory Potential of Trade Herbal Products on Human CYP2D6-Mediated Metabolism and the Influence of Ethanol. Basic Clin Pharmacol Toxicol 2007; 101:350-8. [PMID: 17910620 DOI: 10.1111/j.1742-7843.2007.00121.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The six commonly used trade herbal products, St. John's wort, common valerian, common sage, Ginkgo biloba, Echinacea purpurea and horse chestnut, and ethanol, were investigated for their in vitro inhibitory potential of cytochrome P450 2D6 (CYP2D6)-mediated metabolism. Herbal components were extracted from commercially available products in a way that ensured the same composition of constituents in the extract as in the original trade products. c-DNA baculovirus expressed CYP2D6 was used with dextromethorphan as substrate. Quinidine was included as a positive control inhibitor. A validated high performance liquid chromatography methodology was used to quantify the formation of dextrorphan (product of dextromethorphan O-demethylation). Ethanol showed a biphasic effect on CYP2D6 metabolism, increasing initially the CYP2D6 activity with 175% of control up to a concentration of 1.1%, where after ethanol linearly inhibited the CYP2D6 activity. All the investigated herbs inhibited CYP2D6 activity to some extent, but only St. John's wort, common sage and common valerian were considered possible candidates for in vivo clinically significant effects. They showed IC50 values of 0.07 +/- 7 x 10(-3) mg/ml, 0.8 +/- 0.05 mg/ml and 1.6 +/- 0.2 mg/ml, respectively. St. John's wort inhibited CYP2D6-mediated metabolism in an uncompetitive manner, while common valerian and common sage in a non-competitive manner demonstrated interherb differences in inhibition patterns and differences when compared to the more homogenous competitive inhibitor quinidine. Common valerian was the only herb that showed a mechanistic inhibition of CYP2D6 activity and attention should be paid to a possible toxicity of this herb.
Collapse
Affiliation(s)
- Bent H Hellum
- Department of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
| | | |
Collapse
|
12
|
Hudecek J, Hodek P, Anzenbacherová E, Anzenbacher P. Structural analysis of cytochromes P450 shows differences in flexibility of heme 2- and 4-vinyls. Biochim Biophys Acta Gen Subj 2007; 1770:413-9. [PMID: 17123739 DOI: 10.1016/j.bbagen.2006.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Revised: 09/11/2006] [Accepted: 10/13/2006] [Indexed: 11/29/2022]
Abstract
Structural analysis of the orientations of heme vinyl side chains was carried out using the published crystallographic data for different cytochromes P450. Torsional angles (tau, C(alpha)C(beta)-C(a)C(b)) show different distributions for the vinyls in positions 2 and 4. Whereas the orientation of 2-vinyls is rather restricted (tau between -120 degrees and -180 degrees ), the 4-vinyls have a much higher mobility over almost the entire conformational space. On the basis of the empirical correlation recently reported for peroxidases (M.P. Marzocchi, G. Smulevich, Relationship between heme vinyl conformation and the protein matrix in peroxidases, J. Raman Spectrosc. 34 (2003), 725-736), an attempt has been made to compare the observed vinyl orientations with the experimental frequencies of the vinyl stretching vibrational modes. The data for P450 proteins do not exactly match the peroxidase-derived function, although a qualitatively similar relationship is likely to exist. Differences between P450 forms suggest a variability in heme-region flexibility and in communication with the rest of enzyme.
Collapse
Affiliation(s)
- Jirí Hudecek
- Department of Biochemistry, Faculty of Science, Charles University, Hlavova 2030, 12840 Prague 2, Czech Republic.
| | | | | | | |
Collapse
|
13
|
Bonifacio A, Groenhof AR, Keizers PHJ, de Graaf C, Commandeur JNM, Vermeulen NPE, Ehlers AW, Lammertsma K, Gooijer C, van der Zwan G. Altered spin state equilibrium in the T309V mutant of cytochrome P450 2D6: a spectroscopic and computational study. J Biol Inorg Chem 2007; 12:645-54. [PMID: 17318599 PMCID: PMC1915625 DOI: 10.1007/s00775-007-0210-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Accepted: 01/23/2007] [Indexed: 11/28/2022]
Abstract
Cytochrome P450 2D6 (CYP2D6) is one of the most important cytochromes P450 in humans. Resonance Raman data from the T309V mutant of CYP2D6 show that the substitution of the conserved I-helix threonine situated in the enzyme's active site perturbs the heme spin equilibrium in favor of the six-coordinated low-spin species. A mechanistic hypothesis is introduced to explain the experimental observations, and its compatibility with the available structural and spectroscopic data is tested using quantum-mechanical density functional theory calculations on active-site models for both the CYP2D6 wild type and the T309V mutant.
Collapse
Affiliation(s)
- Alois Bonifacio
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - André R. Groenhof
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Peter H. J. Keizers
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Chris de Graaf
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Jan N. M. Commandeur
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Nico P. E. Vermeulen
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Andreas W. Ehlers
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Koop Lammertsma
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Cees Gooijer
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Gert van der Zwan
- Department of Chemistry and Pharmaceutical Sciences, Sections of Analytical Chemistry and Applied Spectroscopy (ACAS), Organic and Inorganic Chemistry and Molecular Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| |
Collapse
|
14
|
Bonifacio A, Keizers PHJ, Vermeulen NPE, Commandeur JNM, Gooijer C, van der Zwan G. Surface-enhanced resonance Raman scattering of cytochrome P450-2D6 on coated silver hydrosols. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:1860-6. [PMID: 17279667 DOI: 10.1021/la062525w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Surface-enhanced resonance Raman scattering (SERRS) from dilute solutions (down to nanomolar concentrations) of human mono-oxygenase CYP2D6 is observed using aqueous dispersions of Ag nanoparticles (hydrosol) coated with self-assembled monolayers (SAMs) of mercaptoalkanoic acids of two different lengths. From a direct comparison with its resonance Raman spectrum in solution, CYP2D6 appears to fully retain its native structure upon adsorption on coated hydrosol through electrostatic interaction, while a structural change in the active site is observed when uncoated citrate-reduced hydrosol is used. Using SERRS on these biocompatible coated hydrosols, the effects of dextromethorphan on the enzyme's active site can be observed, demonstrating that CYP2D6 ability of binding substrates is preserved. Moreover, by tuning the wavelength of the exciting laser away from the main absorption band of the heme, the vibrational bands of the SAM coating are observed and analyzed to see how the presence of the protein affects the SAM structure.
Collapse
Affiliation(s)
- Alois Bonifacio
- Laser Centre/Analytical Chemistry and Applied Spectroscopy, and LACDR/Molecular Toxicology, Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | | | | | | | | | | |
Collapse
|