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Davidsen JM, Cohen SM, Eisenbrand G, Fukushima S, Gooderham NJ, Guengerich FP, Hecht SS, Rietjens IMCM, Rosol TJ, Harman CL, Taylor SV. FEMA GRAS assessment of derivatives of basil, nutmeg, parsley, tarragon and related allylalkoxybenzene-containing natural flavor complexes. Food Chem Toxicol 2023; 175:113646. [PMID: 36804339 DOI: 10.1016/j.fct.2023.113646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/26/2023] [Accepted: 01/30/2023] [Indexed: 02/18/2023]
Abstract
In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavoring ingredients in food. In this publication, tenth in the series, NFCs containing a high percentage of at least one naturally occurring allylalkoxybenzene constituent with a suspected concern for genotoxicity and/or carcinogenicity are evaluated. In a related paper, ninth in the series, NFCs containing anethole and/or eugenol and relatively low percentages of these allylalkoxybenzenes are evaluated. The Panel applies the threshold of toxicological concern (TTC) concept and evaluates relevant toxicology data on the NFCs and their respective constituent congeneric groups. For NFCs containing allylalkoxybenzene constituent(s), the estimated intake of the constituent is compared to the TTC for compounds with structural alerts for genotoxicity and when exceeded, a margin of exposure (MOE) is calculated. BMDL10 values are derived from benchmark dose analyses using Bayesian model averaging for safrole, estragole and methyl eugenol using EPA's BMDS software version 3.2. BMDL10 values for myristicin, elemicin and parsley apiole were estimated by read-across using relative potency factors. Margins of safety for each constituent congeneric group and MOEs for each allylalkoxybenzene constituent for each NFC were determined that indicate no safety concern. The scope of the safety evaluation contained herein does not include added use in dietary supplements or any products other than food. Ten NFCs, derived from basil, estragon (tarragon), mace, nutmeg, parsley and Canadian snakeroot were determined or affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.
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Affiliation(s)
- Jeanne M Davidsen
- Flavor and Extract Manufacturers Association, 1101 17th Street, N.W., Suite 700, Washington, D.C, 20036, USA
| | - Samuel M Cohen
- Havlik-Wall Professor of Oncology, Dept. of Pathology and Microbiology, University of Nebraska Medical Center, 983135 Nebraska Medical Center, Omaha, NE, 68198-3135, USA
| | - Gerhard Eisenbrand
- University of Kaiserslautern, Germany (Retired), Kühler Grund 48/1, 69126, Heidelberg, Germany
| | - Shoji Fukushima
- Japan Bioassay Research Center, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
| | - Nigel J Gooderham
- Dept. of Metabolism, Digestion, Reproduction, Imperial College London, Sir Alexander Fleming Building, London, SW7 2AZ, United Kingdom
| | - F Peter Guengerich
- Dept. of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
| | - Stephen S Hecht
- Masonic Cancer Center and Dept. of Laboratory Medicine and Pathology, Cancer and Cardiovascular Research Building, 2231 6th St, S.E, Minneapolis, MN, 55455, USA
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University, Stippeneng 6708 WE, Wageningen, the Netherlands
| | - Thomas J Rosol
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, 1 Ohio University, Athens, OH, 45701, USA
| | - Christie L Harman
- Flavor and Extract Manufacturers Association, 1101 17th Street, N.W., Suite 700, Washington, D.C, 20036, USA
| | - Sean V Taylor
- Scientific Secretary to the FEMA Expert Panel, 1101 17th Street, N.W., Suite 700, Washington, D.C, 20036, USA.
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Moreau M, Mallick P, Smeltz M, Haider S, Nicolas CI, Pendse SN, Leonard JA, Linakis MW, McMullen PD, Clewell RA, Clewell HJ, Yoon M. Considerations for Improving Metabolism Predictions for In Vitro to In Vivo Extrapolation. FRONTIERS IN TOXICOLOGY 2022; 4:894569. [PMID: 35573278 PMCID: PMC9099212 DOI: 10.3389/ftox.2022.894569] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 04/13/2022] [Indexed: 12/14/2022] Open
Abstract
High-throughput (HT) in vitro to in vivo extrapolation (IVIVE) is an integral component in new approach method (NAM)-based risk assessment paradigms, for rapidly translating in vitro toxicity assay results into the context of in vivo exposure. When coupled with rapid exposure predictions, HT-IVIVE supports the use of HT in vitro assays for risk-based chemical prioritization. However, the reliability of prioritization based on HT bioactivity data and HT-IVIVE can be limited as the domain of applicability of current HT-IVIVE is generally restricted to intrinsic clearance measured primarily in pharmaceutical compounds. Further, current approaches only consider parent chemical toxicity. These limitations occur because current state-of-the-art HT prediction tools for clearance and metabolite kinetics do not provide reliable data to support HT-IVIVE. This paper discusses current challenges in implementation of IVIVE for prioritization and risk assessment and recommends a path forward for addressing the most pressing needs and expanding the utility of IVIVE.
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Affiliation(s)
- Marjory Moreau
- ScitoVation, LLC, Durham, NC, United States
- *Correspondence: Marjory Moreau,
| | | | | | | | | | | | - Jeremy A. Leonard
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, United States
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Louisse J, Beekmann K, Rietjens IMCM. Use of Physiologically Based Kinetic Modeling-Based Reverse Dosimetry to Predict in Vivo Toxicity from in Vitro Data. Chem Res Toxicol 2016; 30:114-125. [PMID: 27768849 DOI: 10.1021/acs.chemrestox.6b00302] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The development of reliable nonanimal based testing strategies, such as in vitro bioassays, is the holy grail in current human safety testing of chemicals. However, the use of in vitro toxicity data in risk assessment is not straightforward. One of the main issues is that concentration-response curves from in vitro models need to be converted to in vivo dose-response curves. These dose-response curves are needed in toxicological risk assessment to obtain a point of departure to determine safe exposure levels for humans. Recent scientific developments enable this translation of in vitro concentration-response curves to in vivo dose-response curves using physiologically based kinetic (PBK) modeling-based reverse dosimetry. The present review provides an overview of the examples available in the literature on the prediction of in vivo toxicity using PBK modeling-based reverse dosimetry of in vitro toxicity data, showing that proofs-of-principle are available for toxicity end points ranging from developmental toxicity, nephrotoxicity, hepatotoxicity, and neurotoxicity to DNA adduct formation. This review also discusses the promises and pitfalls, and the future perspectives of the approach. Since proofs-of-principle available so far have been provided for the prediction of toxicity in experimental animals, future research should focus on the use of in vitro toxicity data obtained in human models to predict the human situation using human PBK models. This would facilitate human- instead of experimental animal-based approaches in risk assessment.
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Affiliation(s)
- Jochem Louisse
- Division of Toxicology, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Karsten Beekmann
- Division of Toxicology, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands
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Physiologically based kinetic modeling of the bioactivation of myristicin. Arch Toxicol 2016; 91:713-734. [PMID: 27334372 PMCID: PMC5306082 DOI: 10.1007/s00204-016-1752-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 06/08/2016] [Indexed: 11/08/2022]
Abstract
The present study describes physiologically based kinetic (PBK) models for the alkenylbenzene myristicin that were developed by extension of the PBK models for the structurally related alkenylbenzene safrole in rat and human. The newly developed myristicin models revealed that the formation of the proximate carcinogenic metabolite 1′-hydroxymyristicin in liver is at most 1.8 fold higher in rat than in human and limited for the ultimate carcinogenic metabolite 1′-sulfoxymyristicin to (2.8–4.0)-fold higher in human. In addition, a comparison was made between the relative importance of bioactivation for myristicin and safrole. Model predictions indicate that for these related compounds, the formation of the 1′-sulfoxy metabolites in rat and human liver is comparable with a difference of <2.2-fold over a wide dose range. The results from this PBK analysis support that risk assessment of myristicin may be based on the BMDL10 derived for safrole of 1.9–5.1 mg/kg bw per day. Using an estimated daily intake of myristicin of 0.0019 mg/kg bw per day resulting from the use of herbs and spices, this results in MOE values for myristicin that amount to 1000–2700, indicating a priority for risk management. The results obtained illustrate that PBK modeling provides insight into possible species differences in the metabolic activation of myristicin. Moreover, they provide an example of how PBK modeling can facilitate a read-across in risk assessment from a compound for which in vivo toxicity studies are available to a related compound for which tumor data are not reported, thus contributing to alternatives in animal testing.
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Punt A, Paini A, Spenkelink A, Scholz G, Schilter B, van Bladeren PJ, Rietjens IMCM. Evaluation of Interindividual Human Variation in Bioactivation and DNA Adduct Formation of Estragole in Liver Predicted by Physiologically Based Kinetic/Dynamic and Monte Carlo Modeling. Chem Res Toxicol 2016; 29:659-68. [PMID: 26952143 DOI: 10.1021/acs.chemrestox.5b00493] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Estragole is a known hepatocarcinogen in rodents at high doses following metabolic conversion to the DNA-reactive metabolite 1'-sulfooxyestragole. The aim of the present study was to model possible levels of DNA adduct formation in (individual) humans upon exposure to estragole. This was done by extending a previously defined PBK model for estragole in humans to include (i) new data on interindividual variation in the kinetics for the major PBK model parameters influencing the formation of 1'-sulfooxyestragole, (ii) an equation describing the relationship between 1'-sulfooxyestragole and DNA adduct formation, (iii) Monte Carlo modeling to simulate interindividual human variation in DNA adduct formation in the population, and (iv) a comparison of the predictions made to human data on DNA adduct formation for the related alkenylbenzene methyleugenol. Adequate model predictions could be made, with the predicted DNA adduct levels at the estimated daily intake of estragole of 0.01 mg/kg bw ranging between 1.6 and 8.8 adducts in 10(8) nucleotides (nts) (50th and 99th percentiles, respectively). This is somewhat lower than values reported in the literature for the related alkenylbenzene methyleugenol in surgical human liver samples. The predicted levels seem to be below DNA adduct levels that are linked with tumor formation by alkenylbenzenes in rodents, which were estimated to amount to 188-500 adducts per 10(8) nts at the BMD10 values of estragole and methyleugenol. Although this does not seem to point to a significant health concern for human dietary exposure, drawing firm conclusions may have to await further validation of the model's predictions.
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Affiliation(s)
- Ans Punt
- Division of Toxicology, Wageningen University , Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - Alicia Paini
- Division of Toxicology, Wageningen University , Tuinlaan 5, 6703 HE Wageningen, The Netherlands.,Nestlé Research Center , P.O. Box 44, 1000 Lausanne 26, Switzerland
| | - Albertus Spenkelink
- Division of Toxicology, Wageningen University , Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - Gabriele Scholz
- Nestlé Research Center , P.O. Box 44, 1000 Lausanne 26, Switzerland
| | - Benoit Schilter
- Nestlé Research Center , P.O. Box 44, 1000 Lausanne 26, Switzerland
| | - Peter J van Bladeren
- Division of Toxicology, Wageningen University , Tuinlaan 5, 6703 HE Wageningen, The Netherlands.,Nestec S.A , Avenue Nestlé 55, 1800 Vevey, Switzerland
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University , Tuinlaan 5, 6703 HE Wageningen, The Netherlands
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Villarini M, Pagiotti R, Dominici L, Fatigoni C, Vannini S, Levorato S, Moretti M. Investigation of the cytotoxic, genotoxic, and apoptosis-inducing effects of estragole isolated from fennel (Foeniculum vulgare). JOURNAL OF NATURAL PRODUCTS 2014; 77:773-778. [PMID: 24617303 DOI: 10.1021/np400653p] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The present study was undertaken to evaluate, in the HepG2 human hepatoma cell line, the in vitro cytotoxic, genotoxic, and apoptotic activities of estragole (1), contained in the essential oil of Foeniculum vulgare (fennel) and suspected to induce hepatic tumors in susceptible strains of mice. Toward this end, an MTT cytotoxicity assay, a trypan blue dye exclusion test, a double-staining (acridine orange and DAPI) fluorescence viability assay, a single-cell microgel-electrophoresis (comet) assay, a mitochondrial membrane potential (Δψm) assay, and a DNA fragmentation analysis were conducted. In terms of potential genotoxic effects, the comet assay indicated that estragole (1) was not able to induce DNA damage nor apoptosis under the experimental conditions used.
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Affiliation(s)
- Milena Villarini
- Department of Pharmaceutical Sciences (Unit of Public Health), University of Perugia , Via del Giochetto, 06122 Perugia, Italy
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Shoda LKM, Woodhead JL, Siler SQ, Watkins PB, Howell BA. Linking physiology to toxicity using DILIsym®, a mechanistic mathematical model of drug-induced liver injury. Biopharm Drug Dispos 2013; 35:33-49. [DOI: 10.1002/bdd.1878] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 10/10/2013] [Accepted: 11/01/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Lisl K. M. Shoda
- The Hamner-UNC Institute for Drug Safety Sciences; The Hamner Institutes; Research Triangle Park NC 27709 USA
| | - Jeffrey L. Woodhead
- The Hamner-UNC Institute for Drug Safety Sciences; The Hamner Institutes; Research Triangle Park NC 27709 USA
| | - Scott Q. Siler
- The Hamner-UNC Institute for Drug Safety Sciences; The Hamner Institutes; Research Triangle Park NC 27709 USA
| | - Paul B. Watkins
- The Hamner-UNC Institute for Drug Safety Sciences; The Hamner Institutes; Research Triangle Park NC 27709 USA
| | - Brett A. Howell
- The Hamner-UNC Institute for Drug Safety Sciences; The Hamner Institutes; Research Triangle Park NC 27709 USA
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Valcke M, Krishnan K. Characterization of the human kinetic adjustment factor for the health risk assessment of environmental contaminants. J Appl Toxicol 2013; 34:227-40. [PMID: 24038072 DOI: 10.1002/jat.2919] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 07/15/2013] [Indexed: 12/26/2022]
Abstract
A default uncertainty factor of 3.16 (√10) is applied to account for interindividual variability in toxicokinetics when performing non-cancer risk assessments. Using relevant human data for specific chemicals, as WHO/IPCS suggests, it is possible to evaluate, and replace when appropriate, this default factor by quantifying chemical-specific adjustment factors for interindividual variability in toxicokinetics (also referred to as the human kinetic adjustment factor, HKAF). The HKAF has been determined based on the distributions of pharmacokinetic parameters (e.g., half-life, area under the curve, maximum blood concentration) in relevant populations. This article focuses on the current state of knowledge of the use of physiologically based algorithms and models in characterizing the HKAF for environmental contaminants. The recent modeling efforts on the computation of HKAF as a function of the characteristics of the population, chemical and its mode of action (dose metrics), as well as exposure scenario of relevance to the assessment are reviewed here. The results of these studies, taken together, suggest the HKAF varies as a function of the sensitive subpopulation and dose metrics of interest, exposure conditions considered (route, duration, and intensity), metabolic pathways involved and theoretical model underlying its computation. The HKAF seldom exceeded the default value of 3.16, except in very young children (i.e., <≈ 3 months) and when the parent compound is the toxic moiety. Overall, from a public health perspective, the current state of knowledge generally suggest that the default uncertainty factor is sufficient to account for human variability in non-cancer risk assessments of environmental contaminants.
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Affiliation(s)
- Mathieu Valcke
- Département de santé environnementale et santé au travail, Université de Montréal, CP 6128, Succursale Centre-Ville, Montréal, Québec, Canada, H3C 3 J7; Institut national de santé publique du Québec, 190 Boul. Crémazie Est, Montréal, QC, Canada, H2P 1E2
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A physiologically based in silico model for trans-2-hexenal detoxification and DNA adduct formation in human including interindividual variation indicates efficient detoxification and a negligible genotoxicity risk. Arch Toxicol 2013; 87:1725-37. [PMID: 23864024 DOI: 10.1007/s00204-013-1091-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 07/02/2013] [Indexed: 12/23/2022]
Abstract
A number of α,β-unsaturated aldehydes are present in food both as natural constituents and as flavouring agents. Their reaction with DNA due to their electrophilic α,β-unsaturated aldehyde moiety may result in genotoxicity as observed in some in vitro models, thereby raising a safety concern. A question that remains is whether in vivo detoxification would be efficient enough to prevent DNA adduct formation and genotoxicity. In this study, a human physiologically based kinetic/dynamic (PBK/D) model of trans-2-hexenal (2-hexenal), a selected model α,β-unsaturated aldehyde, was developed to examine dose-dependent detoxification and DNA adduct formation in humans upon dietary exposure. The kinetic model parameters for detoxification were quantified using relevant pooled human tissue fractions as well as tissue fractions from 11 different individual subjects. In addition, a Monte Carlo simulation was performed so that the impact of interindividual variation in 2-hexenal detoxification on the DNA adduct formation in the population as a whole could be examined. The PBK/D model revealed that DNA adduct formation due to 2-hexenal exposure was 0.039 adducts/10⁸ nucleotides (nt) at the estimated average 2-hexenal dietary intake (0.04 mg 2-hexenal/kg bw) and 0.18 adducts/10⁸ nt at the 95th percentile of the dietary intake (0.178 mg 2-hexenal/kg bw) in the most sensitive people. These levels are three orders of magnitude lower than natural background DNA adduct levels that have been reported in disease-free humans (6.8-110 adducts/10⁸ nt), suggesting that the genotoxicity risk for the human population at realistic dietary daily intakes of 2-hexenal may be negligible.
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Yoon M, Campbell JL, Andersen ME, Clewell HJ. Quantitativein vitrotoin vivoextrapolation of cell-based toxicity assay results. Crit Rev Toxicol 2012; 42:633-52. [DOI: 10.3109/10408444.2012.692115] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Obolskiy D, Pischel I, Feistel B, Glotov N, Heinrich M. Artemisia dracunculus L. (tarragon): a critical review of its traditional use, chemical composition, pharmacology, and safety. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:11367-84. [PMID: 21942448 DOI: 10.1021/jf202277w] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Artemisia dracunculus L. (tarragon) has a long history of use as a spice and remedy. Two well-described "cultivars" (Russian and French) are used widely and differ in ploidy level, morphology, and chemistry. Key biologically active secondary metabolites are essential oils (0.15-3.1%), coumarins (>1%), flavonoids, and phenolcarbonic acids. In vivo studies mainly in rodents, particularly from Russian sources, highlight potential anti-inflammatory, hepatoprotective, and antihyperglycemic effects. Despite concerns about the toxic effects of two of its main constituents, estragole (up to 82%) and methyleugenol (up to 39%), no acute toxicity or mutagenic activity has been reported at doses relevant for human consumption. Water extracts of A. dracunculus contain very low amounts of estragole and methyleugenol and, therefore, are considered to pose a very limited risk. Overall, a stronger focus on clinical studies and precise taxonomic and phytochemical definition of the source material will be essential for future research efforts.
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Affiliation(s)
- Dmitry Obolskiy
- Center for Pharmacognosy and Phytotherapy, The School of Pharmacy (University of London), 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
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Punt A, Schiffelers MJWA, Jean Horbach G, van de Sandt JJM, Groothuis GMM, Rietjens IMCM, Blaauboer BJ. Evaluation of research activities and research needs to increase the impact and applicability of alternative testing strategies in risk assessment practice. Regul Toxicol Pharmacol 2011; 61:105-14. [PMID: 21782875 DOI: 10.1016/j.yrtph.2011.06.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 06/07/2011] [Accepted: 06/29/2011] [Indexed: 11/20/2022]
Abstract
The present paper aims at identifying strategies to increase the impact and applicability of alternative testing strategies in risk assessment. To this end, a quantitative and qualitative literature evaluation was performed on (a) current research efforts in the development of in vitro methods aiming for alternatives to animal testing, (b) the possibilities and limitations of in vitro methods for regulatory purposes and (c) the potential of physiologically-based kinetic (PBK) modeling to improve the impact and applicability of in vitro methods in risk assessment practice. Overall, the evaluation showed that the focus of state-of-the-art research activities does not seem to be optimally directed at developing in vitro alternatives for those endpoints that are most animal-demanding, such as reproductive and developmental toxicity, and carcinogenicity. A key limitation in the application of in vitro alternatives to such systemic endpoints is that in vitro methods do not provide so-called points of departure, necessary for regulators to set safe exposure limits. PBK-modeling could contribute to overcoming this limitation by providing a method that allows extrapolation of in vitro concentration-response curves to in vivo dose-response curves. However, more proofs of principle are required.
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Affiliation(s)
- Ans Punt
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80176, 3508 TD Utrecht, The Netherlands.
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Fang ZZ, Zhang YY, Wang XL, Cao YF, Huo H, Yang L. Bioactivation of herbal constituents: simple alerts in the complex system. Expert Opin Drug Metab Toxicol 2011; 7:989-1007. [DOI: 10.1517/17425255.2011.586335] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Rietjens IMCM, Louisse J, Punt A. Tutorial on physiologically based kinetic modeling in molecular nutrition and food research. Mol Nutr Food Res 2011; 55:941-56. [DOI: 10.1002/mnfr.201000655] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 02/15/2011] [Accepted: 02/18/2011] [Indexed: 11/11/2022]
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Rietjens IMCM, Al Huseiny W, Boersma MG. Flavonoids and alkenylbenzenes: New concepts in bioactivation studies. Chem Biol Interact 2010; 192:87-95. [PMID: 20863818 DOI: 10.1016/j.cbi.2010.09.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 09/08/2010] [Accepted: 09/14/2010] [Indexed: 11/30/2022]
Abstract
The present paper focuses on the biological reactive intermediates formed from two categories of botanical ingredients: flavonoids and alkenylbenzenes. The paper especially presents an overview of three concepts in bioactivation studies on flavonoids and alkenylbenzenes elucidated by our recent studies. These new concepts include (i) the fact that reactive electrophilic quinone/quinone methide type metabolites of flavonoids may be the intermediates required for the induction of the beneficial gene expression through electrophile responsive element (EpRE)-mediated pathways, pointing at a possible beneficial effect of a reactive intermediate, (ii) the development of physiologically based kinetic (PBK) and physiologically based dynamic (PBD) models providing a new way to obtain insight in levels of formation of biologically reactive and unstable intermediates in vivo at high but also more realistic low dose levels, and (iii) the concept of the matrix effect that should be taken into account when studying the bioactivation of food-borne genotoxic carcinogens including the alkenylbenzenes, the bioactivation of which was shown to be inhibited by flavonoids. Together the results presented reveal that by studying the mode of action (MOA) new concepts in bioactivation studies of importance for future risk assessment and/or risk-benefit assessment of the flavonoids and alkenylbenzenes are obtained.
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Affiliation(s)
- Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE, Wageningen, The Netherlands.
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