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Blaschke U, Felkers E, Hewitt NJ, Kluxen FM, Morgan N, Wiemann C. Proposals for new spray drift exposure values in orchards and vineyards for residents and bystanders. Regul Toxicol Pharmacol 2024; 150:105643. [PMID: 38723936 DOI: 10.1016/j.yrtph.2024.105643] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 04/24/2024] [Accepted: 05/06/2024] [Indexed: 05/13/2024]
Abstract
In the EU, predicted exposure to spray drift for residents and bystanders from applications in orchards and vineyards is based on data from one study published in 1987, where one downwind distance (8 m) was considered. CropLife Europe conducted sixteen new GLP compliant studies in 4 EU countries, 8 in orchards, 8 in vineyards with early and late season applications, using adult and child mannequins located 5, 10 and 15 m downwind from the last row to measure dermal and inhalation exposures. The resulting "Bystander Resident Orchard Vineyard (BROV)" database comprises 288 observations and offers a more comprehensive option for exposure prediction. There were differences between adult and child, crop type, leaf cover and distance from the sprayer, supporting the derivation of mean, median, 75th and 95th percentile exposures for each subset. Exposures did not generally correlate with wind speed, wind direction, sprayer type, spray quality, spray concentration or amount applied. Dermal and inhalation exposure were lower in vineyards than in orchards and further analysis is required to understand why.
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Affiliation(s)
| | | | | | | | - Neil Morgan
- Syngenta, Jealott's Hill International Research Centre, Bracknell, Berkshire, UK.
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2
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Vinck AK, Felkers E, Urtizberea M, Hewitt NJ, Bürling K, Morriss A. Ambient air concentrations of plant protection products: Data collection for the combined air concentration database and associated risk assessment. Regul Toxicol Pharmacol 2024; 149:105627. [PMID: 38621522 DOI: 10.1016/j.yrtph.2024.105627] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 04/02/2024] [Accepted: 04/10/2024] [Indexed: 04/17/2024]
Abstract
CropLife Europe collected literature values from monitoring studies measuring air concentrations of Plant Protection Products (PPPs) that may be inhaled by humans located in rural areas but not immediately adjacent to PPP applications. The resulting "Combined Air Concentration Database" (CACD) was used to determine whether air concentrations of PPPs reported by the French "Agency for Food, Environmental and Occupational Health & Safety" (ANSES) are consistent with those measured by others to increase confidence in values of exposure to humans. The results were put into risk assessment context. Results show that 25-90% of samples do not contain measurable PPP concentrations. Measured respirable fractions were below EU default air concentrations used for risk assessment for resident exposure by the European Food Safety Authority. All measured exposures in the CACD were also below established toxicological endpoints, even when considering the highest maximum average reported concentrations and very conservative inhalation rates. The highest recorded air concentration was for prosulfocarb (0.696 μg/m³ measured over 48 h) which is below the EFSA default limit of 1 μg/m³ for low volatility substances. In conclusion, based on the CACD, measured air concentrations of PPPs are significantly lower than EFSA default limits and relevant toxicological reference values.
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Affiliation(s)
- Anne-Kim Vinck
- Bayer SAS, Crop Science Division, Sophia Antipolis, France
| | - Edgars Felkers
- Bayer AG, Crop Science Division, Monheim am Rhein, Germany.
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3
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Blaschke U, Felkers E, Hewitt NJ, Kluxen FM, Morgan N, Wiemann C. Proposals for new transfer coefficient (TC) values for worker re-entry activities in grape vineyards. Regul Toxicol Pharmacol 2024; 150:105628. [PMID: 38621523 DOI: 10.1016/j.yrtph.2024.105628] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/04/2024] [Accepted: 04/10/2024] [Indexed: 04/17/2024]
Abstract
New transfer coefficient (TC) values were derived for vineyard workers handling treated grapevines during harvesting and crop maintenance activities. Re-entry exposure and dislodgeable foliar residue (DFR) studies were performed in Europe, covering hand harvesting, pruning/training, pruning/tying and pruning/shoot lifting. Foliar applications of fungicides (iprovalicarb, dimethomorph, dithianon, pyrimethanil and fenbuconazole) were made and 73 workers at 16 sites were monitored over one working day. Exposure was measured on inner and outer dosimeters, face/neck wipes and hand washes. In concurrent DFR studies, leaf punches were taken at each site during the time of worker re-entry. Potential exposure values correlated well with DFR values. TC values were derived for various re-entry activities for potential and actual exposure, with and without gloves. The harvesting task resulted in lower TC values than the other crop maintenance tasks. Additional TC values reflecting the use of protective gloves can be derived from the results. The TC values are much lower than current European Food Safety Authority (EFSA) default values. This project addresses a data gap identified by EFSA for specific EU TC values to permit more realistic and reliable re-entry worker exposure estimates for grapes.
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Affiliation(s)
| | | | | | | | - Neil Morgan
- Syngenta, Jealott's Hill International Research Centre, Bracknell, Berkshire, UK.
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4
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Ebmeyer J, Najjar A, Lange D, Boettcher M, Voß S, Brandmair K, Meinhardt J, Kuehnl J, Hewitt NJ, Krueger CT, Schepky A. Next generation risk assessment: an ab initio case study to assess the systemic safety of the cosmetic ingredient, benzyl salicylate, after dermal exposure. Front Pharmacol 2024; 15:1345992. [PMID: 38515841 PMCID: PMC10955127 DOI: 10.3389/fphar.2024.1345992] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 02/12/2024] [Indexed: 03/23/2024] Open
Abstract
We performed an ab initio next-generation risk assessment (NGRA) for a fragrance ingredient, benzyl salicylate (BSal), to demonstrate how cosmetic ingredients can be evaluated for systemic toxicity endpoints based on non-animal approaches. New approach methodologies (NAMs) used to predict the internal exposure included skin absorption assays, hepatocyte metabolism, and physiologically based pharmacokinetic (PBPK) modeling, and potential toxicodynamic effects were assessed using pharmacology profiling, ToxProfiler cell stress assay, transcriptomics in HepG2 and MCF-7 cells, ReproTracker developmental and reproductive toxicology (DART) assays, and cytotoxicity assays in human kidney cells. The outcome of the NGRA was compared to that of the traditional risk assessment approach based on animal data. The identification of the toxicologically critical entity was a critical step that directed the workflow and the selection of chemicals for PBPK modeling and testing in bioassays. The traditional risk assessment and NGRA identified salicylic acid (SA) as the "toxdriver." A deterministic PBPK model for a single-day application of 1.54 g face cream containing 0.5% BSal estimated the Cmax for BSal (1 nM) to be much lower than that of its major in vitro metabolite, SA (93.2 nM). Therefore, SA was tested using toxicodynamics bioassays. The lowest points of departure (PoDs) were obtained from the toxicogenomics assays. The interpretation of these results by two companies and methods were similar (SA only results in significant gene deregulation in HepG2 cells), but PoD differed (213 μM and 10.6 µM). A probabilistic PBPK model for repeated applications of the face cream estimated the highest Cmax of SA to be 630 nM. The resulting margins of internal exposure (MoIE) using the PoDs were 338 and 16, which were more conservative than those derived from external exposure and in vivo PoDs (margin of safety values were 9,705). In conclusion, both traditional and ab initio NGRA approaches concluded that the daily application of BSal in a cosmetic leave-on face cream at 0.5% is safe for humans. The processing and interpretation of toxicogenomics data can lead to different PoDs, which can subsequently affect the calculation of the MoIE. This case study supports the use of NAMs in a tiered NGRA ab initio approach.
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Brandmair K, Tao TP, Gerlach S, Przibilla J, Schepky A, Marx U, Hewitt NJ, Kühnl J, Maschmeyer I. Suitability of different reconstructed human skin models in the skin and liver Chip2 microphysiological model to investigate the kinetics and first-pass skin metabolism of the hair dye, 4-amino-2-hydroxytoluene. J Appl Toxicol 2024; 44:333-343. [PMID: 37699698 DOI: 10.1002/jat.4542] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/25/2023] [Accepted: 08/25/2023] [Indexed: 09/14/2023]
Abstract
The HUMIMIC skin-liver Chip2 microphysiological systems model using the epidermal model, EpiDerm™, was reported previously to mimic application route-dependent metabolism of the hair dye, 4-amino-2-hydroxytoluene (AHT). Therefore, we evaluated the use of alternative skin models-SkinEthic™, EpiDermFT™ and PhenionFT™-for the same purpose. In static incubations, AHT permeation was similar using SkinEthic™ and EpiDerm™ models. Older Day 21 (D21) SkinEthic™ models with a thicker stratum corneum did not exhibit a greater barrier to AHT (overall permeation was the same in D17 and D21 models). All epidermal models metabolised AHT, with the EpiDerm™ exhibiting higher N-acetylation than SkinEthic™ models. AHT metabolism by D21 SkinEthic™ models was lower than that by D17 SkinEthic™ and EpiDerm™ models, thus a thicker stratum corneum was associated with fewer viable cells and a lower metabolic activity. AHT permeation was much slower using PhenionFT™ compared to epidermal models and better reflected permeation of AHT through native human skin. This model also extensively metabolised AHT to N-acetyl-AHT. After a single topical or systemic application of AHT to Chip2 model with PhenionFT™, medium was analysed for parent and metabolites over 5 days. The first-pass metabolism of AHT was demonstrated, and the introduction of a wash step after 30 min decreased the exposure to AHT and its metabolites by 33% and 40%-43%, respectively. In conclusion, epidermal and FT skin models used in the Chip2 can mimic the first-pass skin metabolism of AHT. This highlights the flexibility of the Chip2 to incorporate different skin models according to the purpose.
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Affiliation(s)
| | - Thi-Phuong Tao
- TissUse GmbH, Oudenarder Str. 16, D-13347, Berlin, Germany
| | - Silke Gerlach
- Beiersdorf AG, Unnastraße 48, D-20253, Hamburg, Germany
| | - Julia Przibilla
- Pharmacelsus GmbH, Science Park 2, D-66123, Saarbrücken, Germany
| | | | - Uwe Marx
- TissUse GmbH, Oudenarder Str. 16, D-13347, Berlin, Germany
| | - Nicola J Hewitt
- Cosmetics Europe, Avenue Herrmann-Debroux 40, 1160, Auderghem, Belgium
| | - Jochen Kühnl
- Beiersdorf AG, Unnastraße 48, D-20253, Hamburg, Germany
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Yin XJ, Hewitt NJ, Erler S, Bryson P, Blömeke B, Gaspari AA, Goebel C. Safety assessment for nail cosmetics: Framework for the estimation of systemic exposure through the nail plate. Regul Toxicol Pharmacol 2024; 148:105588. [PMID: 38423269 DOI: 10.1016/j.yrtph.2024.105588] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/19/2024] [Accepted: 02/19/2024] [Indexed: 03/02/2024]
Abstract
All cosmetics products, including nail care products, must be evaluated for their safety. The assessment of systemic exposure is a key component of the safety assessment. However, data on the exposure, especially via ungual route (nail plate) are limited. Based on the physicochemical properties of human nails and permeability data of topical onychomycosis drugs, the nail plate is considered a good barrier to chemicals. We examine factors impacting penetration of nail care ingredients through the nail plate, including properties of the nails of the ingredients and formulations. The molecular weight, vapor pressure, logP, water solubility, and keratin binding, as well as formulations properties e.g., polymerization of acrylate monomers are considered important factors affecting penetration. To estimate systemic exposure of nail care ingredients through the nail plate, a standardized framework is applied that quantifies the impacts of these properties on penetration with an adjustment factor for each of these influencing properties. All the adjustment factors are then consolidated to derive an integrated adjustment factor which can be used for calculation of the systemic exposure dose for the ingredient. Several case studies are presented to reflect how this framework can be used in the exposure assessment for nail cosmetic products.
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Affiliation(s)
- Xuejun J Yin
- OPI, Wella Company, 4500 Park Granada, Calabasas, CA, USA
| | | | - Steffen Erler
- Beiersdorf AG, Beiersdorfstraβe 1-9, 22529, Hamburg, Germany
| | - Paul Bryson
- OPI, Wella Company, 4500 Park Granada, Calabasas, CA, USA
| | | | - Anthony A Gaspari
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Carsten Goebel
- Wella Company, Berliner Allee 65, 64295, Darmstadt, Germany.
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7
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Tao TP, Brandmair K, Gerlach S, Przibilla J, Schepky A, Marx U, Hewitt NJ, Maschmeyer I, Kühnl J. Application of a skin and liver Chip2 microphysiological model to investigate the route-dependent toxicokinetics and toxicodynamics of consumer-relevant doses of genistein. J Appl Toxicol 2024; 44:287-300. [PMID: 37700462 DOI: 10.1002/jat.4540] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/25/2023] [Accepted: 08/27/2023] [Indexed: 09/14/2023]
Abstract
The HUMMIC skin-liver Chip2 microphysiological system using EpiDerm™ and HepaRG and stellate liver spheroids was used to evaluate the route-specific metabolism and toxicodynamic effects of genistein. Human-relevant exposure levels were compared: 60 nM representing the plasma concentration expected after topical application of a cosmetic product and 1 μM representing measured plasma concentrations after ingesting soya products. Genistein was applied as single and repeated topical and/or systemic doses. The kinetics of genistein and its metabolites were measured over 5 days. Toxicodynamic effects were measured using transcriptional analyses of skin and liver organoids harvested on Days 2 and 5. Route-specific differences in genistein's bioavailability were observed, with first-pass metabolism (sulfation) occurring in the skin after topical application. Only repeated application of 1 μM, resembling daily oral intake of soya products, induced statistically significant changes in gene expression in liver organoids only. This was concomitant with a much higher systemic concentration of genistein which was not reached in any other dosing scenario. This suggests that single or low doses of genistein are rapidly metabolised which limits its toxicodynamic effects on the liver and skin. Therefore, by facilitating longer and/or repeated applications, the Chip2 can support safety assessments by linking relevant gene modulation with systemically available parent or metabolite(s). The rate of metabolism was in accordance with the short half-life observed in in vivo in humans, thus supporting the relevance of the findings. In conclusion, the skin-liver Chip2 provides route-specific information on metabolic fate and toxicodynamics that may be relevant to safety assessment.
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Li H, Bunglawala F, Hewitt NJ, Pendlington R, Cubberley R, Nicol B, Spriggs S, Baltazar M, Cable S, Dent M. ADME characterization and PBK model development of 3 highly protein-bound UV filters through topical application. Toxicol Sci 2023; 196:1-15. [PMID: 37584694 PMCID: PMC10613959 DOI: 10.1093/toxsci/kfad081] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023] Open
Abstract
Estimating human exposure in the safety assessment of chemicals is crucial. Physiologically based kinetic (PBK) models which combine information on exposure, physiology, and chemical properties, describing the absorption, distribution, metabolism, and excretion (ADME) processes of a chemical, can be used to calculate internal exposure metrics such as maximum concentration and area under the concentration-time curve in plasma or tissues of a test chemical in next-generation risk assessment. This article demonstrates the development of PBK models for 3 UV filters, specifically octyl methoxycinnamate, octocrylene, and 4-methylbenzylidene camphor. The models were parameterized entirely based on data obtained from in vitro and/or in silico methods in a bottom-up modeling approach and then validated based on human dermal pharmacokinetic (PK) data. The 3 UV filters are "difficult to test" in in vitro test systems due to high lipophilicity, high binding affinity for proteins, and nonspecific binding, for example, toward plastic. This research work presents critical considerations in ADME data generation, interpretation, and parameterization to assure valid PBK model development to increase confidence in using PBK modeling to help make safety decisions in the absence of human PK data. The developed PBK models of the 3 chemicals successfully simulated the plasma concentration profiles of clinical PK data following dermal application, indicating the reliability of the ADME data generated and the parameters determined. The study also provides insights and lessons learned for characterizing ADME and developing PBK models for highly lipophilic and protein-bound chemicals in the future.
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Affiliation(s)
- Hequn Li
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Fazila Bunglawala
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | | | - Ruth Pendlington
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Richard Cubberley
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Beate Nicol
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Sandrine Spriggs
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Maria Baltazar
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Sophie Cable
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
| | - Matthew Dent
- Unilever Safety and Environmental Assurance Centre, Sharnbrook MK44 1LQ, UK
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Bowden AM, Escher SE, Rose J, Sadekar N, Patlewicz G, O'Keeffe L, Bury D, Hewitt NJ, Giusti A, Rothe H. Workshop report: Challenges faced in developing inhalation thresholds of Toxicological Concern (TTC) - State of the science and next steps. Regul Toxicol Pharmacol 2023; 142:105434. [PMID: 37302561 PMCID: PMC10494708 DOI: 10.1016/j.yrtph.2023.105434] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/30/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
A challenging step in human risk assessment of chemicals is the derivation of safe thresholds. The Threshold of Toxicological Concern (TTC) concept is one option which can be used for the safety evaluation of substances with a limited toxicity dataset, but for which exposure is sufficiently low. The application of the TTC is generally accepted for orally or dermally exposed cosmetic ingredients; however, these values cannot directly be applied to the inhalation route because of differences in exposure route versus oral and dermal. Various approaches of an inhalation TTC concept have been developed over recent years to address this. A virtual workshop organized by Cosmetics Europe, held in November 2020, shared the current state of the science regarding the applicability of existing inhalation TTC approaches to cosmetic ingredients. Key discussion points included the need for an inhalation TTC for local respiratory tract effects in addition to a systemic inhalation TTC, dose metrics, database building and quality of studies, definition of the chemical space and applicability domain, and classification of chemicals with different potencies. The progress made to date in deriving inhalation TTCs was highlighted, as well as the next steps envisaged to develop them further for regulatory acceptance and use.
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Affiliation(s)
- Anthony M Bowden
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, UK.
| | | | | | - Nikaeta Sadekar
- Research Institute for Fragrance Materials, Inc., Mahwah, NJ, USA
| | - Grace Patlewicz
- Center for Computational and Exposure, US Environmental Protection Agency, RTP, NC, 27711, USA
| | | | - Dagmar Bury
- L'Oréal Research & Innovation, Clichy, France
| | | | | | - Helga Rothe
- SciConT (formerly at Coty), Darmstadt, Germany
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Tao TP, Maschmeyer I, LeCluyse EL, Rogers E, Brandmair K, Gerlach S, Przibilla J, Kern F, Genies C, Jacques C, Najjar A, Schepky A, Marx U, Kühnl J, Hewitt NJ. Development of a microphysiological skin-liver-thyroid Chip3 model and its application to evaluate the effects on thyroid hormones of topically applied cosmetic ingredients under consumer-relevant conditions. Front Pharmacol 2023; 14:1076254. [PMID: 36843954 PMCID: PMC9946709 DOI: 10.3389/fphar.2023.1076254] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 01/17/2023] [Indexed: 02/10/2023] Open
Abstract
All cosmetic ingredients registered in Europe must be evaluated for their safety using non-animal methods. Microphysiological systems (MPS) offer a more complex higher tier model to evaluate chemicals. Having established a skin and liver HUMIMIC Chip2 model demonstrating how dosing scenarios impact the kinetics of chemicals, we investigated whether thyroid follicles could be incorporated to evaluate the potential of topically applied chemicals to cause endocrine disruption. This combination of models in the HUMIMIC Chip3 is new; therefore, we describe here how it was optimized using two chemicals known to inhibit thyroid production, daidzein and genistein. The MPS was comprised of Phenion® Full Thickness skin, liver spheroids and thyroid follicles co-cultured in the TissUse HUMIMIC Chip3. Endocrine disruption effects were determined according to changes in thyroid hormones, thyroxine (T4) and 3,3',5-triiodothyronine (T3). A main part of the Chip3 model optimization was the replacement of freshly isolated thyroid follicles with thyrocyte-derived follicles. These were used in static incubations to demonstrate the inhibition of T4 and T3 production by genistein and daidzein over 4 days. Daidzein exhibited a lower inhibitory activity than genistein and both inhibitory activities were decreased after a 24 h preincubation with liver spheroids, indicating metabolism was via detoxification pathways. The skin-liver-thyroid Chip3 model was used to determine a consumer-relevant exposure to daidzein present in a body lotion based on thyroid effects. A "safe dose" of 0.235 μg/cm2 i.e., 0.047% applied in 0.5 mg/cm2 of body lotion was the highest concentration of daidzein which does not result in changes in T3 and T4 levels. This concentration correlated well with the value considered safe by regulators. In conclusion, the Chip3 model enabled the incorporation of the relevant exposure route (dermal), metabolism in the skin and liver, and the bioactivity endpoint (assessment of hormonal balance i.e., thyroid effects) into a single model. These conditions are closer to those in vivo than 2D cell/tissue assays lacking metabolic function. Importantly, it also allowed the assessment of repeated doses of chemical and a direct comparison of systemic and tissue concentrations with toxicodynamic effects over time, which is more realistic and relevant for safety assessment.
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Affiliation(s)
| | | | | | - Eda Rogers
- LifeNet Health, Virginia Beach, VA, United States
| | | | | | | | | | | | | | | | | | | | | | - Nicola J. Hewitt
- Cosmetics Europe, Auderghem, Belgium,*Correspondence: Nicola J. Hewitt,
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Najjar A, Ellison CA, Gregoire S, Hewitt NJ. Correction to: Practical application of the interim internal threshold of toxicological concern (iTTC): a case study based on clinical data. Arch Toxicol 2023; 97:311. [PMID: 36437304 PMCID: PMC9816225 DOI: 10.1007/s00204-022-03398-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Corie A. Ellison
- The Procter & Gamble Company, 8700 Mason Montgomery Road, Cincinnati, OH 45040 USA
| | - Sebastien Gregoire
- L’Oreal Research & Innovation, 1, Avenue Eugène Schueller, 93601 Aulnay-sous-Bois, France
| | - Nicola J. Hewitt
- Cosmetics Europe, Avenue Herrmann-Debroux 40, 1160 Brussels, Belgium
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12
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Najjar A, Ellison CA, Gregoire S, Hewitt NJ. Practical application of the interim internal threshold of toxicological concern (iTTC): a case study based on clinical data. Arch Toxicol 2023; 97:155-164. [PMID: 36149470 PMCID: PMC9816204 DOI: 10.1007/s00204-022-03371-6] [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: 08/05/2022] [Accepted: 08/25/2022] [Indexed: 01/19/2023]
Abstract
We present a case study that provides a practical step-by-step example of how the internal Threshold of Toxicological Concern (iTTC) can be used as a tool to refine a TTC-based assessment for dermal exposures to consumer products. The case study uses a theoretical scenario where there are no systemic toxicity data for the case study chemicals (avobenzone, oxybenzone, octocrylene, homosalate, octisalate, octinoxate, and ecamsule). Human dermal pharmacokinetic data following single and repeat dermal exposure to products containing the case study chemicals were obtained from data published by the US FDA. The clinical studies utilized an application procedure that followed maximal use conditions (product applied as 2 mg/cm2 to 75% of the body surface area, 4 times a day). The case study chemicals were first reviewed to determine if they were in the applicability domain of the iTTC, and then, the human plasma concentrations were compared to an iTTC limit of 1 µM. When assessed under maximum usage, the external exposure of all chemicals exceeded the external dose TTC limits. By contrast, the internal exposure to all chemicals, except oxybenzone, was an order of magnitude lower than the 1 µM interim iTTC threshold. This work highlights the importance of understanding internal exposure relative to external dose and how the iTTC can be a valuable tool for assessing low-level internal exposures; additionally, the work demonstrates how to use an iTTC, and highlights considerations and refinement opportunities for the approach.
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Affiliation(s)
| | - Corie A Ellison
- The Procter & Gamble Company, 8700 Mason Montgomery Road, Cincinnati, OH, 45040, USA.
| | - Sebastien Gregoire
- L'Oreal Research & Innovation, 1, Avenue Eugène Schueller, 93601, Aulnay-sous-Bois, France
| | - Nicola J Hewitt
- Cosmetics Europe, Avenue Herrmann-Debroux 40, 1160, Brussels, Belgium
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13
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Kuster CJ, Hewitt NJ, Hamacher G. Dermal measurement of exposure to plant protection products: Actual hand exposure from hand washing vs. wearing cotton gloves. Front Public Health 2022; 10:1037780. [PMID: 36589982 PMCID: PMC9798894 DOI: 10.3389/fpubh.2022.1037780] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
For the authorization of plant protection products, a quantitative non-dietary exposure risk assessment relies on established dermal exposure models, measured mainly using passive dosimetry. Exposure to the hands is determined via hand washing or using cotton gloves as a surrogate for skin. This study compared both methods using operator exposure data available from the Agricultural Operator Exposure Model (AOEM) project report. These data indicate that hand exposure determined using cotton gloves resulted in markedly higher exposure values for all exposure scenarios compared to those determined by hand washes. One explanation for this is that dermal uptake of the residues reduces the amount of residue that can be recovered by hand washing. Uncertainty due to dermal uptake can be addressed by either default assumptions or by specific dermal absorption data. However, this cannot solely account for the large difference observed between the values and is mainly likely to be due to the higher capacity of the cotton gloves vs. human skin to retain residues. The results further indicate that the variability between hand wash samples and cotton glove samples differs between the exposure scenarios. Hence, the level of conservatism related to the use of cotton gloves as surrogate skin remains unknown. In conclusion, this evaluation of the AOEM data indicates that the cotton glove method results in much higher levels of measured hand exposure than the hand wash method. It cannot be excluded that dermal uptake has contributed to that result. However, the findings suggest the higher retention capacity of cotton gloves vs. human skin to be the main impact parameter. The cotton glove method does not provide the results with regards to the protection level that can be expected from the use of protective gloves. Therefore, we believe that the application of the hand wash method is a more accurate measure of exposure levels, if either specific dermal absorption data or, in its absence, default assumptions are applied as adjustment factor.
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Affiliation(s)
- Christian J. Kuster
- Bayer AG, Crop Science Division, Monheim, Germany,*Correspondence: Christian J. Kuster
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14
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Felkers E, Kluxen FM, Adham S, Vinck AK, Hewitt NJ, Morgan N. Measured air concentrations of pesticides for the estimation of exposure to vapour in European risk assessments. Regul Toxicol Pharmacol 2022; 136:105285. [DOI: 10.1016/j.yrtph.2022.105285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 09/28/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
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15
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Hewitt NJ, Troutman J, Przibilla J, Schepky A, Ouédraogo G, Mahony C, Kenna G, Varçin M, Dent MP. Use of in vitro metabolism and biokinetics assays to refine predicted in vivo and in vitro internal exposure to the cosmetic ingredient, phenoxyethanol, for use in risk assessment. Regul Toxicol Pharmacol 2022; 131:105132. [PMID: 35217105 DOI: 10.1016/j.yrtph.2022.105132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 12/20/2021] [Accepted: 01/31/2022] [Indexed: 01/04/2023]
Abstract
A novel approach was developed to help characterize the biokinetics of the cosmetic ingredient, phenoxyethanol, to help assess the safety of the parent and its major stable metabolite. In the first step of this non-animal tiered approach, primary human hepatocytes were used to confirm or refute in silico predicted metabolites, and elucidate the intrinsic clearance of phenoxyethanol. A key result was the identification of the major metabolite, phenoxyacetic acid (PAA), the exposure to which in the kidney was subsequently predicted to far exceed that of phenoxyethanol in blood or other tissues. Therefore, a novel aspect of this approach was to measure in the subsequent step the formation of PAA in the cells dosed with phenoxyethanol that were used to provide points of departure (PoDs) and express the intracellular exposure as the Cmax and AUC24. This enabled the calculation of the intracellular concentrations of parent and metabolite at the PoD in the cells used to derive this value. These concentrations can be compared with in vivo tissue levels to conclude on the safety margin. The lessons from this case study will help to inform the design of other non-animal safety assessments.
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Affiliation(s)
- Nicola J Hewitt
- Cosmetics Europe, Avenue Herrmann-Debroux 40, 1160, Auderghem, Belgium
| | | | - Julia Przibilla
- Pharmacelsus GmbH, Science Park 2, D-66123, Saarbrücken, Germany
| | | | - Gladys Ouédraogo
- L'Oréal, Research & Innovation, 9 rue Pierre Dreyfus, 92110, Clichy, France
| | | | - Gerry Kenna
- Drug Safety Consultant, 2 Farmfield Drive, Macclesfield, Cheshire, SK10 2TJ, UK
| | - Mustafa Varçin
- Cosmetics Europe, Avenue Herrmann-Debroux 40, 1160, Auderghem, Belgium
| | - Mathew P Dent
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedfordshire, MK44 1LQ, UK
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16
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Najjar A, Schepky A, Krueger CT, Dent M, Cable S, Li H, Grégoire S, Roussel L, Noel-Voisin A, Hewitt NJ, Cardamone E. Use of Physiologically-Based Kinetics Modelling to Reliably Predict Internal Concentrations of the UV Filter, Homosalate, After Repeated Oral and Topical Application. Front Pharmacol 2022; 12:802514. [PMID: 35058784 PMCID: PMC8763688 DOI: 10.3389/fphar.2021.802514] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 11/22/2021] [Indexed: 01/09/2023] Open
Abstract
Ethical and legal considerations have led to increased use of non-animal methods to evaluate the safety of chemicals for human use. We describe the development and qualification of a physiologically-based kinetics (PBK) model for the cosmetic UV filter ingredient, homosalate, to support its safety without the need of generating further animal data. The intravenous (IV) rat PBK model, using PK-Sim®, was developed and validated using legacy in vivo data generated prior to the 2013 EU animal-testing ban. Input data included literature or predicted physicochemical and pharmacokinetic properties. The refined IV rat PBK model was subject to sensitivity analysis to identify homosalate-specific sensitive parameters impacting the prediction of Cmax (more sensitive than AUC(0-∞)). These were then considered, together with population modeling, to calculate the confidence interval (CI) 95% Cmax and AUC(0-∞). Final model parameters were established by visual inspection of the simulations and biological plausibility. The IV rat model was extrapolated to oral administration, and used to estimate internal exposures to doses tested in an oral repeated dose toxicity study. Next, a human PBK dermal model was developed using measured human in vitro ADME data and a module to represent the dermal route. Model performance was confirmed by comparing predicted and measured values from a US-FDA clinical trial (Identifier: NCT03582215, https://clinicaltrials.gov/). Final exposure estimations were obtained in a virtual population and considering the in vitro and input parameter uncertainty. This model was then used to estimate the Cmax and AUC(0–24 h) of homosalate according to consumer use in a sunscreen. The developed rat and human PBK models had a good biological basis and reproduced in vivo legacy rat and human clinical kinetics data. They also complied with the most recent WHO and OECD recommendations for assessing the confidence level. In conclusion, we have developed a PBK model which predicted reasonably well the internal exposure of homosalate according to different exposure scenarios with a medium to high level of confidence. In the absence of in vivo data, such human PBK models will be the heart of future completely non-animal risk assessments; therefore, valid approaches will be key in gaining their regulatory acceptance. Clinical Trial Registration: https://clinicaltrials.gov/, identifier, NCT03582215
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Affiliation(s)
| | | | | | - Matthew Dent
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, United Kingdom
| | - Sophie Cable
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, United Kingdom
| | - Hequn Li
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, United Kingdom
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17
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Alexander-White C, Bury D, Cronin M, Dent M, Hack E, Hewitt NJ, Kenna G, Naciff J, Ouedraogo G, Schepky A, Mahony C, Europe C. A 10-step framework for use of read-across (RAX) in next generation risk assessment (NGRA) for cosmetics safety assessment. Regul Toxicol Pharmacol 2022; 129:105094. [PMID: 34990780 DOI: 10.1016/j.yrtph.2021.105094] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 07/12/2021] [Accepted: 12/02/2021] [Indexed: 02/07/2023]
Abstract
This paper presents a 10-step read-across (RAX) framework for use in cases where a threshold of toxicological concern (TTC) approach to cosmetics safety assessment is not possible. RAX builds on established approaches that have existed for more than two decades using chemical properties and in silico toxicology predictions, by further substantiating hypotheses on toxicological similarity of substances, and integrating new approach methodologies (NAM) in the biological and kinetic domains. NAM include new types of data on biological observations from, for example, in vitro assays, toxicogenomics, metabolomics, receptor binding screens and uses physiologically-based kinetic (PBK) modelling to inform about systemic exposure. NAM data can help to substantiate a mode/mechanism of action (MoA), and if similar chemicals can be shown to work by a similar MoA, a next generation risk assessment (NGRA) may be performed with acceptable confidence for a data-poor target substance with no or inadequate safety data, based on RAX approaches using data-rich analogue(s), and taking account of potency or kinetic/dynamic differences.
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Affiliation(s)
- Camilla Alexander-White
- MKTox & Co Ltd, 36 Fairford Crescent, Downhead Park, Milton Keynes, Buckinghamshire, MK15 9AQ, UK.
| | - Dagmar Bury
- L'Oreal Research & Innovation, 9 Rue Pierre Dreyfus, 92110, Clichy, France
| | - Mark Cronin
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 AF, UK
| | - Matthew Dent
- Unilever, Safety & Environmental Assurance Centre, Colworth House, Sharnbrook, Bedfordshire, MK44 1ET, UK
| | - Eric Hack
- ScitoVation, Research Triangle Park, Durham, NC, USA
| | - Nicola J Hewitt
- Cosmetics Europe, 40 Avenue Hermann-Debroux, 1160, Brussels, Belgium
| | - Gerry Kenna
- Cosmetics Europe, 40 Avenue Hermann-Debroux, 1160, Brussels, Belgium
| | - Jorge Naciff
- The Procter & Gamble Company, Cincinnati, OH, 45040, USA
| | - Gladys Ouedraogo
- L'Oreal Research & Innovation, 1 Avenue Eugène Schueller, Aulnay sous bois, France
| | | | | | - Cosmetics Europe
- Cosmetics Europe, 40 Avenue Hermann-Debroux, 1160, Brussels, Belgium.
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18
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Birk B, Haake V, Sperber S, Herold M, Wallisch SK, Huener HA, Verlohner A, Amma MM, Walk T, Hernandez TR, Hewitt NJ, Kamp H, van Ravenzwaay B. Use of in vitro metabolomics in NRK cells to help predicting nephrotoxicity and differentiating the MoA of nephrotoxicants. Toxicol Lett 2021; 353:43-59. [PMID: 34626816 DOI: 10.1016/j.toxlet.2021.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 08/06/2021] [Accepted: 09/29/2021] [Indexed: 12/25/2022]
Abstract
We describe a strategy using an in vitro metabolomics assay with tubular rat NRK-52E cells to investigate the Modes of Action (MoAs) of nephrotoxic compounds. Chemicals were selected according to their MoAs based on literature information: acetaminophen, 4-aminophenol and S-(trichlorovinyl-)L-cysteine (TCVC), (covalent protein binding); gentamycin, vancomycin, polymycin B and CdCl2 (lysosomal overload) and tenofovir and cidofovir (mitochondrial DNA-interaction). After treatment and harvesting of the cells, intracellular endogenous metabolites were quantified relative to vehicle control. Metabolite patterns were evaluated in a purely data-driven pattern generation process excluding published information. This strategy confirmed the assignment of the chemicals to the respective MoA except for TCVC and CdCl2. Finally, TCVC was defined as unidentified and CdCl2 was reclassified to the MoA "covalent protein binding". Hierarchical cluster analysis of 58 distinct metabolites from the patterns enabled a clear visual separation of chemicals in each MoA. The assay reproducibility was very good and metabolic responses were consistent. These results support the use of metabolome analysis in NRK-52E cells as a suitable tool for understanding and investigating the MoA of nephrotoxicants. This assay could enable the early identification of nephrotoxic compounds and finally reduce animal testing.
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Affiliation(s)
- Barbara Birk
- Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany.
| | | | - Saskia Sperber
- Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | | | | | | | | | - Meike M Amma
- Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | | | | | | | - Hennicke Kamp
- Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany; BASF Metabolome Solutions GmbH, Berlin, Germany
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19
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Pfuhler S, Downs TR, Hewitt NJ, Hoffmann S, Mun GC, Ouedraogo G, Roy S, Curren RD, Aardema MJ. Validation of the 3D reconstructed human skin micronucleus (RSMN) assay: an animal-free alternative for following-up positive results from standard in vitro genotoxicity assays. Mutagenesis 2021; 36:1-17. [PMID: 33544138 PMCID: PMC8081377 DOI: 10.1093/mutage/geaa035] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 11/25/2020] [Indexed: 11/13/2022] Open
Abstract
In vitro test batteries have become the standard approach to determine the genotoxic potential of substances of interest across industry sectors. While useful for hazard identification, standard in vitro genotoxicity assays in 2D cell cultures have limited capability to predict in vivo outcomes and may trigger unnecessary follow-up animal studies or the loss of promising substances where animal tests are prohibited or not desired. To address this problem, a team of regulatory, academia and industry scientists was established to develop and validate 3D in vitro human skin-based genotoxicity assays for use in testing substances with primarily topical exposure. Validation of the reconstructed human skin micronucleus (RSMN) assay in MatTek Epi-200™ skin models involved testing 43 coded chemicals selected by independent experts, in four US/European laboratories. The results were analysed by an independent statistician according to predefined criteria. The RSMN assay showed a reproducibly low background micronucleus frequency and exhibited sufficient capacity to metabolise pro-mutagens. The overall RSMN accuracy when compared to in vivo genotoxicity outcomes was 80%, with a sensitivity of 75% and a specificity of 84%, and the between- and within-laboratory reproducibility was 77 and 84%, respectively. A protocol involving a 72-h exposure showed increased sensitivity in detecting true positive chemicals compared to a 48-h exposure. An analysis of a test strategy using the RSMN assay as a follow-up test for substances positive in standard in vitro clastogenicity/aneugenicity assays and a reconstructed skin Comet assay for substances with positive results in standard gene mutation assays results in a sensitivity of 89%. Based on these results, the RSMN assay is considered sufficiently validated to establish it as a ‘tier 2’ assay for dermally exposed compounds and was recently accepted into the OECD’s test guideline development program.
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Affiliation(s)
| | | | | | | | - Greg C Mun
- Institute for In Vitro Sciences, Inc., Gaithersburg, MD, USA
| | | | | | - Rodger D Curren
- Institute for In Vitro Sciences, Inc., Gaithersburg, MD, USA
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20
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Morgan N, Hewitt NJ, Felkers E, Wiemann C, Kluxen FM, Kuster CJ. Dose Setting for Dermal Absorption Studies on Dried Foliar Residues. Ann Work Expo Health 2021; 65:397-405. [PMID: 33582764 DOI: 10.1093/annweh/wxaa139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 11/11/2020] [Accepted: 12/15/2020] [Indexed: 11/13/2022] Open
Abstract
Currently, the standard approach to estimate systemic exposure of workers after contact with dried pesticide residues on crops during re-entry activities relies on using the highest identified dermal absorption value for aqueous spray dilutions. However, recent dermal absorption studies with dried residues and their respective in-use dilutions have shown that this is likely to significantly overestimate their dermal penetration potential and, thus, predicted systemic exposure. The choice of appropriate dose levels for these dermal absorption studies has not been defined. Moreover, actual skin loading during re-entry tasks may differ significantly from that achieved by applying a fixed volume of an aqueous dilution, which is the standard practice in generic dermal absorption studies. To address this, we propose an approach to dose setting for dried residue studies within the current European risk assessment framework. Skin loading for studies can be calculated from the existing exposure algorithms and by taking appropriate body surface areas into account. Thus, skin loading in studies will vary depending on the exact nature and duration of the task and the region of the body exposed, reflecting actual exposure scenarios.
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Affiliation(s)
- Neil Morgan
- Syngenta, Jealott's Hill International Research Centre, Bracknell, Berkshire, UK
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21
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Bury D, Alexander-White C, Clewell HJ, Cronin M, Desprez B, Detroyer A, Efremenko A, Firman J, Hack E, Hewitt NJ, Kenna G, Klaric M, Lester C, Mahony C, Ouedraogo G, Paini A, Schepky A. New framework for a non-animal approach adequately assures the safety of cosmetic ingredients - A case study on caffeine. Regul Toxicol Pharmacol 2021; 123:104931. [PMID: 33905778 DOI: 10.1016/j.yrtph.2021.104931] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/11/2021] [Accepted: 04/13/2021] [Indexed: 11/19/2022]
Abstract
This case study on the model substance caffeine demonstrates the viability of a 10-step read-across (RAX) framework in practice. New approach methodologies (NAM), including RAX and physiologically-based kinetic (PBK) modelling were used to assess the consumer safety of caffeine. Appropriate animal systemic toxicity data were used from the most relevant RAX analogue while assuming that no suitable animal toxicity data were available for caffeine. Based on structural similarities, three primary metabolites of the target chemical caffeine (theophylline, theobromine and paraxanthine) were selected as its most relevant analogues, to estimate a point of departure in order to support a next generation risk assessment (NGRA). On the basis of the pivotal mode of action (MOA) of caffeine and other methylxanthines, theophylline appeared to be the most potent and suitable analogue. A worst-case aggregate exposure assessment determined consumer exposure to caffeine from different sources, such as cosmetics and food/drinks. Using a PBK model to estimate human blood concentrations following exposure to caffeine, an acceptable Margin of Internal Exposure (MOIE) of 27-fold was derived on the basis of a RAX using theophylline animal data, which suggests that the NGRA approach for caffeine is sufficiently conservative to protect human health.
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Affiliation(s)
- Dagmar Bury
- L'Oréal, Research & Innovation, 9 Rue Pierre Dreyfus, 92110, Clichy, France.
| | - Camilla Alexander-White
- MKTox & Co Ltd, 36 Fairford Crescent, Downhead Park, Milton Keynes, Buckinghamshire, MK15 9AQ, UK
| | - Harvey J Clewell
- Ramboll Health Sciences, 3107 Armand Street, Monroe, LA, 71201, USA
| | - Mark Cronin
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 AF, UK
| | - Bertrand Desprez
- Cosmetics Europe, 40 Avenue Hermann-Debroux, 1160, Brussels, Belgium
| | - Ann Detroyer
- L'Oréal, Research & Innovation, 1 Avenue Eugène Schueller, Aulnay-sous-Bois, France
| | | | - James Firman
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 AF, UK
| | - Eric Hack
- ScitoVation, Research Triangle Park, Durham, NC, USA
| | | | - Gerry Kenna
- Cosmetics Europe, 40 Avenue Hermann-Debroux, 1160, Brussels, Belgium
| | - Martina Klaric
- Cosmetics Europe, 40 Avenue Hermann-Debroux, 1160, Brussels, Belgium
| | | | | | - Gladys Ouedraogo
- L'Oréal, Research & Innovation, 1 Avenue Eugène Schueller, Aulnay-sous-Bois, France
| | - Alicia Paini
- European Commission Joint Research Centre, Ispra, Italy
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Tao TP, Brandmair K, Gerlach S, Przibilla J, Géniès C, Jacques-Jamin C, Schepky A, Marx U, Hewitt NJ, Maschmeyer I, Kühnl J. Demonstration of the first-pass metabolism in the skin of the hair dye, 4-amino-2-hydroxytoluene, using the Chip2 skin-liver microphysiological model. J Appl Toxicol 2021; 41:1553-1567. [PMID: 33594739 DOI: 10.1002/jat.4146] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/22/2021] [Accepted: 01/22/2021] [Indexed: 12/30/2022]
Abstract
We used TissUse's HUMIMIC Chip2 microfluidic model, incorporating reconstructed skin models and liver spheroids, to investigate the impact of consumer-relevant application scenarios on the metabolic fate of the hair dye, 4-amino-2-hydroxytoluene (AHT). After a single topical or systemic application of AHT to Chip2 models, medium was analysed for parent and metabolites over 5 days. The metabolic profile of a high dose (resulting in a circuit concentration of 100 μM based on 100% bioavailability) of AHT was the same after systemic and topical application to 96-well EpiDerm™ models. Additional experiments indicated that metabolic capacity of EpiDerm™ models were saturated at this dose. At 2.5 μM, concentrations of AHT and several of its metabolites differed between application routes. Topical application resulted in a higher Cmax and a 327% higher area under the curve (AUC) of N-acetyl-AHT, indicating a first-pass effect in the EpiDerm™ models. In accordance with in vivo observations, there was a concomitant decrease in the Cmax and AUC of AHT-O-sulphate after topical, compared with systemic application. A similar alteration in metabolite ratios was observed using a 24-well full-thickness skin model, EpiDermFT™, indicating that a first-pass effect was also possible to detect in a more complex model. In addition, washing the EpiDermFT™ after 30 min, thus reflecting consumer use, decreased the systemic exposure to AHT and its metabolites. In conclusion, the skin-liver Chip2 model can be used to (a) recapitulate the first-pass effect of the skin and alterations in the metabolite profile of AHT observed in vivo and (b) provide consumer-relevant data regarding leave-on/rinse-off products.
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Affiliation(s)
| | - Katrin Brandmair
- Front End Innovation, department of toxicology, Beiersdorf AG, Hamburg, Germany
| | - Silke Gerlach
- Front End Innovation, department of toxicology, Beiersdorf AG, Hamburg, Germany
| | - Julia Przibilla
- ADMET & in vitro Pharmacology, Pharmacelsus GmbH, Saarbrücken, Germany
| | - Camille Géniès
- Department of applied research: pharmacology, Pierre Fabre Dermo-Cosmétique, Toulouse, France
| | - Carine Jacques-Jamin
- Department of applied research: pharmacology, Pierre Fabre Dermo-Cosmétique, Toulouse, France
| | - Andreas Schepky
- Front End Innovation, department of toxicology, Beiersdorf AG, Hamburg, Germany
| | - Uwe Marx
- Contract development, TissUse GmbH, Berlin, Germany
| | | | | | - Jochen Kühnl
- Front End Innovation, department of toxicology, Beiersdorf AG, Hamburg, Germany
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23
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Ellison CA, Api AM, Becker RA, Efremenko AY, Gadhia S, Hack CE, Hewitt NJ, Varcin M, Schepky A. Internal Threshold of Toxicological Concern (iTTC): Where We Are Today and What Is Possible in the Near Future. Front Toxicol 2021; 2:621541. [PMID: 35296119 PMCID: PMC8915896 DOI: 10.3389/ftox.2020.621541] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 12/18/2020] [Indexed: 11/30/2022] Open
Abstract
The Threshold of Toxicological Concern (TTC) is a risk assessment tool for evaluating low-level exposure to chemicals with limited toxicological data. A next step in the ongoing development of TTC is to extend this concept further so that it can be applied to internal exposures. This refinement of TTC based on plasma concentrations, referred to as internal TTC (iTTC), attempts to convert the chemical-specific external NOAELs (in mg/kg/day) in the TTC database to an estimated internal exposure. A multi-stakeholder collaboration formed, with the aim of establishing an iTTC suitable for human safety risk assessment. Here, we discuss the advances and future directions for the iTTC project, including: (1) results from the systematic literature search for metabolism and pharmacokinetic data for the 1,251 chemicals in the iTTC database; (2) selection of ~350 chemicals that will be included in the final iTTC; (3) an overview of the in vitro caco-2 and in vitro hepatic metabolism studies currently being generated for the iTTC chemicals; (4) demonstrate how PBPK modeling is being utilized to convert a chemical-specific external NOAEL to an internal exposure; (5) perspective on the next steps in the iTTC project.
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Affiliation(s)
- Corie A Ellison
- The Procter and Gamble Company, Cincinnati, OH, United States
| | - Anne Marie Api
- Research Institute for Fragrance Materials, Woodcliff Lake, NJ, United States
| | | | - Alina Y Efremenko
- ScitoVation, Limited Liability Company (LLC), Durham, NC, United States
| | - Sanket Gadhia
- Research Institute for Fragrance Materials, Woodcliff Lake, NJ, United States
| | - C Eric Hack
- ScitoVation, Limited Liability Company (LLC), Durham, NC, United States
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24
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Ellison CA, Tankersley KO, Obringer CM, Carr GJ, Manwaring J, Rothe H, Duplan H, Géniès C, Grégoire S, Hewitt NJ, Jamin CJ, Klaric M, Lange D, Rolaki A, Schepky A. Partition coefficient and diffusion coefficient determinations of 50 compounds in human intact skin, isolated skin layers and isolated stratum corneum lipids. Toxicol In Vitro 2020; 69:104990. [DOI: 10.1016/j.tiv.2020.104990] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/18/2020] [Accepted: 08/27/2020] [Indexed: 11/24/2022]
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Kühnl J, Tao TP, Brandmair K, Gerlach S, Rings T, Müller-Vieira U, Przibilla J, Genies C, Jaques-Jamin C, Schepky A, Marx U, Hewitt NJ, Maschmeyer I. Characterization of application scenario-dependent pharmacokinetics and pharmacodynamic properties of permethrin and hyperforin in a dynamic skin and liver multi-organ-chip model. Toxicology 2020; 448:152637. [PMID: 33220337 DOI: 10.1016/j.tox.2020.152637] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 12/12/2022]
Abstract
Microphysiological systems (MPS) aim to mimic the dynamic microenvironment and the interaction between tissues. While MPS exist for investigating pharmaceuticals, the applicability of MPS for cosmetics ingredients is yet to be evaluated. The HUMIMIC Chip2 ("Chip2″), is the first multi-organ chip technology to incorporate skin models, allowing for the topical route to be tested. Therefore, we have used this model to analyze the impact of different exposure scenarios on the pharmacokinetics and pharmacodynamics of two topically exposed chemicals, hyperforin and permethrin. The Chip2 incorporated reconstructed human epidermis models (EpiDerm™) and HepaRG-stellate spheroids. Initial experiments using static incubations of single organoids helped determine the optimal dose. In the Chip2 studies, parent and metabolites were analyzed in the circuit over 5 days after application of single and repeated topical or systemic doses. The gene expression of relevant xenobiotic metabolizing enzymes in liver spheroids was measured to reflect toxicodynamics effects of the compounds in liver. The results show that 1) metabolic capacities of EpiDerm™ and liver spheroids were maintained over five days; 2) EpiDerm™ model barrier function remained intact; 3) repeated application of compounds resulted in higher concentrations of parent chemicals and most metabolites compared to single application; 4) compound-specific gene induction e.g. induction of CYP3A4 by hyperforin depended on the application route and frequency; 5) different routes of application influenced the systemic concentrations of both parents and metabolites in the chip over the course of the experiment; 6) there was excellent intra- and inter-lab reproducibility. For permethrin, a process similar to the excretion in a human in vivo study could be simulated which was remarkably comparable to the in vivo situation. These results support the use of the Chip2 model to provide information on parent and metabolite disposition that may be relevant to risk assessment of topically applied cosmetics ingredients.
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Affiliation(s)
- Jochen Kühnl
- Beiersdorf AG, Unnastraße 48, D-20253, Hamburg, Germany.
| | - Thi Phuong Tao
- TissUse GmbH, Oudenarder Str. 16, D-13347, Berlin, Germany
| | | | - Silke Gerlach
- Beiersdorf AG, Unnastraße 48, D-20253, Hamburg, Germany
| | - Thamée Rings
- Beiersdorf AG, Unnastraße 48, D-20253, Hamburg, Germany
| | | | - Julia Przibilla
- Pharmacelsus GmbH, Science Park 2, D-66123, Saarbrücken, Germany
| | | | | | | | - Uwe Marx
- TissUse GmbH, Oudenarder Str. 16, D-13347, Berlin, Germany
| | - Nicola J Hewitt
- Cosmetics Europe, Avenue Herrmann-Debroux 40, 1160, Auderghem, Belgium
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Lester C, Hewitt NJ, Müller-Vieira U, Mayer M, Ellison C, Duplan H, Genies C, Jacques-Jamin C, Fabian E, Sorrell I, Lange D, Schepky A, Grégoire S. Metabolism and plasma protein binding of 16 straight- and branched-chain parabens in in vitro liver and skin models. Toxicol In Vitro 2020; 72:105051. [PMID: 33188879 DOI: 10.1016/j.tiv.2020.105051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/24/2020] [Accepted: 11/06/2020] [Indexed: 11/25/2022]
Abstract
Parabens are alkyl esters of 4-hydroxybenzoic acid (4-HBA), with short-chain parabens used as antimicrobials in cosmetics. We investigated the impact of chain structure on skin and liver metabolism. Incubations with primary human hepatocytes and human liver S9 indicated that methyl-, ethyl-, propyl- and butylparaben were rapidly metabolized to similar metabolites, including 4-HBA plus the corresponding alcohols. Liver and EpiSkin™ S9 were used to investigate the metabolism of 16 short and long straight- and branched-chain parabens. The rate of hydrolysis generally decreased with increasing chain length in liver S9, whereas the reverse was true for EpiSkin™ S9. Chain length also correlated with the number of metabolites, with more oxidized metabolites detected from longer chain parabens. The identity of the alcohol group impacted metabolism the most, in terms of the rate of metabolism and the contribution of cofactors. The majority of parabens (13/16) exhibited high plasma protein binding (PPB) (>90%); whereas, 4-HBA PPB was 38%. PPB was related to the LogP of the parabens. In conclusion, the major and common paraben metabolite in PHH, liver S9 and EpiSkin™ S9 was 4-HBA. The rate of metabolism, type of metabolite and contribution of hydrolysis was tissue-specific (liver, skin) and was influenced by the chain length (and hence LogP), structural isomeric form (straight vs branched), and/or the identity of the alkyl group. SHORT ABSTRACT: We investigated how the chain structure of parabens affects their metabolism by liver and EpiSkin™ S9. The major and common metabolite in primary human hepatocytes, liver S9 and EpiSkin™ S9 was 4-HBA plus the corresponding alcohols. The rate of metabolism, type of metabolite and contribution of hydrolysis was tissue-specific and influenced by the chain length, structural isomeric form (straight vs branched), and/or the identity of the alkyl group. Most parabens exhibited high PPB (>90%), whereas the PPB of 4-HBA was 38%.
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Affiliation(s)
| | | | | | - Manuela Mayer
- Pharmacelsus GmbH, Science Park 2, 66123 Saarbrücken, Germany
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Luijten M, Corvi R, Mehta J, Corvaro M, Delrue N, Felter S, Haas B, Hewitt NJ, Hilton G, Holmes T, Jacobs MN, Jacobs A, Lamplmair F, Lewis D, Madia F, Manou I, Melching-Kollmuss S, Schorsch F, Schütte K, Sewell F, Strupp C, van der Laan JW, Wolf DC, Wolterink G, Woutersen R, Zvonar Z, Heusinkveld H, Braakhuis H. A comprehensive view on mechanistic approaches for cancer risk assessment of non-genotoxic agrochemicals. Regul Toxicol Pharmacol 2020; 118:104789. [PMID: 33035627 DOI: 10.1016/j.yrtph.2020.104789] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/14/2020] [Accepted: 10/04/2020] [Indexed: 11/28/2022]
Abstract
Currently the only methods for non-genotoxic carcinogenic hazard assessment accepted by most regulatory authorities are lifetime carcinogenicity studies. However, these involve the use of large numbers of animals and the relevance of their predictive power and results has been scientifically challenged. With increased availability of innovative test methods and enhanced understanding of carcinogenic processes, it is believed that tumour formation can now be better predicted using mechanistic information. A workshop organised by the European Partnership on Alternative Approaches to Animal Testing brought together experts to discuss an alternative, mechanism-based approach for cancer risk assessment of agrochemicals. Data from a toolbox of test methods for detecting modes of action (MOAs) underlying non-genotoxic carcinogenicity are combined with information from subchronic toxicity studies in a weight-of-evidence approach to identify carcinogenic potential of a test substance. The workshop included interactive sessions to discuss the approach using case studies. These showed that fine-tuning is needed, to build confidence in the proposed approach, to ensure scientific correctness, and to address different regulatory needs. This novel approach was considered realistic, and its regulatory acceptance and implementation can be facilitated in the coming years through continued dialogue between all stakeholders and building confidence in alternative approaches.
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Affiliation(s)
- Mirjam Luijten
- National Institute for Public Health and the Environment (RIVM), Centre for Health Protection, Bilthoven, the Netherlands.
| | - Raffaella Corvi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | | | - Nathalie Delrue
- Organisation for Economic Cooperation and Development (OECD), Paris, France
| | | | - Bodo Haas
- Federal Institute for Drugs and Medical Devices, Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | | | - Gina Hilton
- PETA International Science Consortium Ltd, London, UK
| | | | - Miriam N Jacobs
- Centre for Radiation, Chemical and Environmental Hazards (CRCE), Public Health England, UK
| | | | - Franz Lamplmair
- European Commission, DG Internal Market, Industry, Entrepreneurship and SMEs, Brussels, Belgium
| | | | - Federica Madia
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Irene Manou
- EPAA Industry Secretariat, Brussels, Belgium
| | | | | | | | - Fiona Sewell
- National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
| | | | | | - Douglas C Wolf
- Syngenta Crop Protection, LLC, Greensboro, North Carolina, USA
| | - Gerrit Wolterink
- National Institute for Public Health and the Environment (RIVM), Centre for Nutrition, Prevention and Health Services, Bilthoven, the Netherlands
| | - Ruud Woutersen
- TNO Innovation for Life, Zeist; Wageningen University and Research, Wageningen, the Netherlands
| | | | - Harm Heusinkveld
- National Institute for Public Health and the Environment (RIVM), Centre for Health Protection, Bilthoven, the Netherlands
| | - Hedwig Braakhuis
- National Institute for Public Health and the Environment (RIVM), Centre for Health Protection, Bilthoven, the Netherlands
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Eilstein J, Grégoire S, Fabre A, Arbey E, Géniès C, Duplan H, Rothe H, Ellison C, Cubberley R, Schepky A, Lange D, Klaric M, Hewitt NJ, Jacques‐Jamin C. Use of human liver and EpiSkin™ S9 subcellular fractions as a screening assays to compare the in vitro hepatic and dermal metabolism of 47 cosmetics‐relevant chemicals. J Appl Toxicol 2020; 40:416-433. [DOI: 10.1002/jat.3914] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 09/24/2019] [Accepted: 09/24/2019] [Indexed: 11/09/2022]
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Hewitt NJ, Grégoire S, Cubberley R, Duplan H, Eilstein J, Ellison C, Lester C, Fabian E, Fernandez J, Géniès C, Jacques-Jamin C, Klaric M, Rothe H, Sorrell I, Lange D, Schepky A. Measurement of the penetration of 56 cosmetic relevant chemicals into and through human skin using a standardized protocol. J Appl Toxicol 2019; 40:403-415. [PMID: 31867769 PMCID: PMC7027575 DOI: 10.1002/jat.3913] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 09/30/2019] [Accepted: 09/30/2019] [Indexed: 11/09/2022]
Abstract
OECD test guideline 428 compliant protocol using human skin was used to test the penetration of 56 cosmetic‐relevant chemicals. The penetration of finite doses (10 μL/cm2) of chemicals was measured over 24 hours. The dermal delivery (DD) (amount in the epidermis, dermis and receptor fluid [RF]) ranged between 0.03 ± 0.02 and 72.61 ± 8.89 μg/cm2. The DD of seven chemicals was comparable with in vivo values. The DD was mainly accounted for by the amount in the RF, although there were some exceptions, particularly of low DD chemicals. While there was some variability due to cell outliers and donor variation, the overall reproducibility was very good. As six chemicals had to be applied in 100% ethanol due to low aqueous solubility, we compared the penetration of four chemicals with similar physicochemical properties applied in ethanol and phosphate‐buffered saline. Of these, the DD of hydrocortisone was the same in both solvents, while the DD of propylparaben, geraniol and benzophenone was lower in ethanol. Some chemicals displayed an infinite dose kinetic profile; whereas, the cumulative absorption of others into the RF reflected the finite dosing profile, possibly due to chemical volatility, total absorption, chemical precipitation through vehicle evaporation or protein binding (or a combination of these). These investigations provide a substantial and consistent set of skin penetration data that can help improve the understanding of skin penetration, as well as improve the prediction capacity of in silico skin penetration models. The penetration of 56 chemicals was tested in human skin using a standard protocol. Dermal delivery correlated with the amount in the receptor fluid (RF). The impact of solvent on penetration was evaluated. Despite finite doses being applied, different profiles of cumulative absorption kinetics into the RF were observed. These data may help understand skin penetration and improve the prediction capacity of in silico skin penetration models.
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Affiliation(s)
| | | | | | | | - Joan Eilstein
- L'Oreal Research and Innovation, Aulnay-Sous-Bois, France
| | | | - Cathy Lester
- The Procter and Gamble Company, Cincinnati, Ohio
| | | | | | | | | | | | - Helga Rothe
- Procter and Gamble (currently Coty), Darmstadt, Germany
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30
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Sachinidis A, Albrecht W, Nell P, Cherianidou A, Hewitt NJ, Edlund K, Hengstler JG. Road Map for Development of Stem Cell-Based Alternative Test Methods. Trends Mol Med 2019; 25:470-481. [PMID: 31130451 DOI: 10.1016/j.molmed.2019.04.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/28/2019] [Accepted: 04/02/2019] [Indexed: 12/12/2022]
Abstract
Much progress has been made in establishing strategies for differentiation of induced human pluripotent stem cells (hiPSCs). However, differentiated hiPSCs are not yet routinely used for prediction of toxicity. Here, limiting factors are summarised and possibilities for improvement are discussed, with a focus on hepatocytes, cardiomyocytes, tubular epithelial cells, and developmental toxicity. Moreover, we make recommendations for further fine-tuning of differentiation protocols for hiPSCs to hepatocyte-like cells by comparing individual steps of currently available protocols to the mechanisms occurring during embryonic development. A road map is proposed to facilitate test system development, including a description of the most useful performance metrics.
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Affiliation(s)
- Agapios Sachinidis
- Institute of Neurophysiology and Centre for Molecular Medicine Cologne (CMMC), University of Cologne (UKK), Cologne, Germany.
| | - Wiebke Albrecht
- Leibniz Research Centre for Working Environment and Human Factors, Technical University of Dortmund (IfADo), 44139 Dortmund, Germany
| | - Patrick Nell
- Leibniz Research Centre for Working Environment and Human Factors, Technical University of Dortmund (IfADo), 44139 Dortmund, Germany
| | - Anna Cherianidou
- Institute of Neurophysiology and Centre for Molecular Medicine Cologne (CMMC), University of Cologne (UKK), Cologne, Germany
| | | | - Karolina Edlund
- Leibniz Research Centre for Working Environment and Human Factors, Technical University of Dortmund (IfADo), 44139 Dortmund, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors, Technical University of Dortmund (IfADo), 44139 Dortmund, Germany.
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31
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Ellison CA, Blackburn KL, Carmichael PL, Clewell HJ, Cronin MTD, Desprez B, Escher SE, Ferguson SS, Grégoire S, Hewitt NJ, Hollnagel HM, Klaric M, Patel A, Salhi S, Schepky A, Schmitt BG, Wambaugh JF, Worth A. Challenges in working towards an internal threshold of toxicological concern (iTTC) for use in the safety assessment of cosmetics: Discussions from the Cosmetics Europe iTTC Working Group workshop. Regul Toxicol Pharmacol 2019; 103:63-72. [PMID: 30653989 PMCID: PMC6644721 DOI: 10.1016/j.yrtph.2019.01.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/02/2019] [Accepted: 01/07/2019] [Indexed: 11/22/2022]
Abstract
The Threshold of Toxicological Concern (TTC) is an important risk assessment tool which establishes acceptable low-level exposure values to be applied to chemicals with limited toxicological data. One of the logical next steps in the continued evolution of TTC is to develop this concept further so that it is representative of internal exposures (TTC based on plasma concentration). An internal TTC (iTTC) would provide threshold values that could be utilized in exposure-based safety assessments. As part of a Cosmetics Europe (CosEu) research program, CosEu has initiated a project that is working towards the development of iTTCs that can be used for the human safety assessment. Knowing that the development of an iTTC is an ambitious and broad-spanning topic, CosEu organized a Working Group comprised a balance of multiple stakeholders (cosmetics and chemical industries, the EPA and JRC and academia) with relevant experience and expertise and workshop to critically evaluate the requirements to establish an iTTC. Outcomes from the workshop included an evaluation on the current state of the science for iTTC, the overall iTTC strategy, selection of chemical databases, capture and curation of chemical information, ADME and repeat dose data, expected challenges, as well as next steps and ongoing work.
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Affiliation(s)
- Corie A Ellison
- The Procter & Gamble Company, Cincinnati, OH, United States.
| | | | - Paul L Carmichael
- Unilever Safety and Environmental Assurance Center, Bedfordshire, UK
| | | | - Mark T D Cronin
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, England, UK
| | | | - Sylvia E Escher
- Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany
| | - Steve S Ferguson
- National Institute of Environmental Health Sciences, North Carolina, United States
| | | | | | | | | | - Atish Patel
- Research Institute for Fragrance Materials, New Jersey, United States
| | | | | | | | - John F Wambaugh
- United States Environmental Protection Agency, National Center for Computational Toxicology, North Carolina, United States
| | - Andrew Worth
- European Commission, Joint Research Centre, Ispra, Italy
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32
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Grégoire S, Cubberley R, Duplan H, Eilstein J, Hewitt NJ, Jacques-Jamin C, Genies C, Klaric M, Rothe H, Ellison C, Fernandez J, Schepky A. Use of a Simple in vitro Test to Assess Loss of Chemical due to Volatility during an in vitro Human Skin Absorption Study. Skin Pharmacol Physiol 2019; 32:117-124. [PMID: 30889606 DOI: 10.1159/000497105] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/18/2019] [Indexed: 11/19/2022]
Abstract
BACKGROUND We tested the cutaneous distribution of 50 chemicals in frozen human skin. The mass balance (MB) values for 48% of the chemicals were < 90%, possibly due to evaporation. METHODS We confirmed the reduction in MB was due to evaporation for two chemicals tested in skin penetration experiments using a carbon filter above the skin to trap airborne chemical. An in vitro assay was used to predict the reduction in MB due to evaporation by comparing the recovery of chemicals after 4 h of incubation at room temperature in open and closed vials. RESULTS Evaporative losses in vitro correlated well with measured MBs (i.e., < 90%) in skin penetration experiments (R2 = 0.81). There was a correlation of the MB with the vapour pressure (VP) which could be used to group chemicals according to their likelihood to evaporate during the course of a skin penetration study. There was also a correlation of MB with Henry's law constants, melting and boiling points. CONCLUSION Our data support the use of a quick and simple test for volatility to account for the loss of MB in skin penetration experiment due to volatility. The best parameter to indicate the potential of a chemical to evaporate is the VP.
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Affiliation(s)
| | | | | | - Joan Eilstein
- L'Oreal Research and Innovation, Aulnay-sous-Bois, France
| | | | | | | | | | - Helga Rothe
- Procter & Gamble (currently Coty), Darmstadt, Germany
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33
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Géniès C, Jamin EL, Debrauwer L, Zalko D, Person EN, Eilstein J, Grégoire S, Schepky A, Lange D, Ellison C, Roe A, Salhi S, Cubberley R, Hewitt NJ, Rothe H, Klaric M, Duplan H, Jacques-Jamin C. Comparison of the metabolism of 10 chemicals in human and pig skin explants. J Appl Toxicol 2018; 39:385-397. [PMID: 30345528 PMCID: PMC6587507 DOI: 10.1002/jat.3730] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 08/13/2018] [Accepted: 08/22/2018] [Indexed: 01/24/2023]
Abstract
Skin metabolism is important to consider when assessing local toxicity and/or penetration of chemicals and their metabolites. If human skin supply is limited, pig skin can be used as an alternative. To identify any species differences, we have investigated the metabolism of 10 chemicals in a pig and human skin explant model. Phase I metabolic pathways in skin from both species included those known to occur via cytochrome P450s, esterases, alcohol dehydrogenases and aldehyde dehydrogenases. Common Phase II pathways were glucuronidation and sulfation but other conjugation pathways were also identified. Chemicals not metabolized by pig skin (caffeine, IQ and 4‐chloroaniline) were also not metabolized by human skin. Six chemicals metabolized by pig skin were metabolized to a similar extent (percentage parent remaining) by human skin. Human skin metabolites were also detected in pig skin incubations, except for one unidentified minor vanillin metabolite. Three cinnamyl alcohol metabolites were unique to pig skin but represented minor metabolites. There were notable species differences in the relative amounts of common metabolites. The difference in the abundance of the sulfate conjugates of resorcinol and 4‐amino‐3‐nitrophenol was in accordance with the known lack of aryl sulfotransferase activity in pigs. In conclusion, while qualitative comparisons of metabolic profiles were consistent between pig and human skin, there were some quantitative differences in the percentage of metabolites formed. This preliminary assessment suggests that pig skin is metabolically competent and could be a useful tool for evaluating potential first‐pass metabolism before testing in human‐derived tissues. We have investigated the metabolism of 10 chemicals in viable pig and human skin. Phase I and II metabolic pathways were present in skin from both species. Chemicals not metabolized by pig skin were also not metabolized by human skin. Six chemicals metabolized by pig skin were also metabolized to a similar extent by human skin. Pig and human skin produced common metabolites, although some species differences were observed and as their relative amounts differed.
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Affiliation(s)
- C Géniès
- Pierre Fabre Dermo-Cosmétique, Toulouse, France
| | - E L Jamin
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, Toulouse, France
| | - L Debrauwer
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, Toulouse, France
| | - D Zalko
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, Toulouse, France
| | - E N Person
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, Toulouse, France
| | | | | | | | - D Lange
- Beiersdorf AG, Hamburg, Germany
| | - C Ellison
- The Procter & Gamble Company, Cincinnati, OH, USA
| | - A Roe
- The Procter & Gamble Company, Cincinnati, OH, USA
| | | | | | | | | | - M Klaric
- Cosmetics Europe, Brussels, Belgium
| | - H Duplan
- Pierre Fabre Dermo-Cosmétique, Toulouse, France
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Desprez B, Dent M, Keller D, Klaric M, Ouédraogo G, Cubberley R, Duplan H, Eilstein J, Ellison C, Grégoire S, Hewitt NJ, Jacques-Jamin C, Lange D, Roe A, Rothe H, Blaauboer BJ, Schepky A, Mahony C. A strategy for systemic toxicity assessment based on non-animal approaches: The Cosmetics Europe Long Range Science Strategy programme. Toxicol In Vitro 2018; 50:137-146. [DOI: 10.1016/j.tiv.2018.02.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 02/26/2018] [Accepted: 02/27/2018] [Indexed: 12/26/2022]
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35
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Zeller A, Pfuhler S, Albertini S, Bringezu F, Czich A, Dietz Y, Fautz R, Hewitt NJ, Kirst A, Kasper P. A critical appraisal of the sensitivity of in vivo genotoxicity assays in detecting human carcinogens. Mutagenesis 2018; 33:179-193. [DOI: 10.1093/mutage/gey005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 03/20/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Andreas Zeller
- Pharmaceutical Sciences, pRED Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse, Basel, Switzerland
| | - Stefan Pfuhler
- Procter & Gamble, Global Product Stewardship, Human Safety, Mason Business Centre, Mason, OH, USA
| | - Silvio Albertini
- Pharmaceutical Sciences, pRED Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse, Basel, Switzerland
| | | | - Andreas Czich
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt, Germany
| | - Yasmin Dietz
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt, Germany
| | | | | | | | - Peter Kasper
- Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee, Bonn, Germany
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Abstract
Metabolism in fresh and cryopreserved (CP) rat, dog and monkey hepatocyte suspensions and cultures was measured using midazolam (CYP3A), tolbutamide (CYP2C), dextromethorphan (CYP2D) and p-nitrophenol (glucuronosyl S-transferases (UGT), sulphotransferases (ST)). CYP3A, CYP2C9, CYP2D6, UGT and ST enzyme functions in fresh and CP rat, dog and monkey hepatocyte suspensions were retained - CP rat hepatocytes lost some CYP2C activity but this was restored by adding NADPH or by placing the cells in culture, suggesting that the enzyme was still functional. Phase 2 activities were equivalent in fresh and CP hepatocyte suspensions. In some cases, incubation conditions increased the rate of metabolism, possibly reflecting de novo cofactor synthesis. However, this effect was substrate and species dependent and was not always the same in fresh and CP cells. CYP3A, CYP2C, CYP2D, UGT and ST activities at 24 hours of culture of rat and monkey hepatocytes were not compromised by cryopreservation. CYP3A, CYP2D but not CYP2C were lower in 24-hour cultures of CP dog hepatocytes than in fresh cells. Despite being lower than fresh cells, UGT activity in dog CP hepatocytes did not decrease from 0 to 24 hours of culture. Speciesspecific metabolism of p-nitrophenol could be demonstrated in both CP cell suspensions and cultures. In conclusion, these data suggest that the enzyme characteristics of fresh and CP hepatocytes from each species and under specific incubation conditions should be considered when carrying out metabolism studies of new compounds.
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Affiliation(s)
- Nicola J Hewitt
- In Vitro Technologies Inc., 1450 South Rolling Road, Baltimore, MD 21227, USA.
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Pant K, Bruce S, Sly J, Klug Laforce M, Springer S, Cecil M, Andrus E, Dakoulas E, Wagner VO, Hewitt NJ, Kulkarni R. Bacterial mutagenicity assays: Vehicle and positive control results from the standard Ames assay, the 6- and 24-well miniaturized plate incorporation assays and the Ames II™ assay. Environ Mol Mutagen 2016; 57:483-496. [PMID: 27198925 DOI: 10.1002/em.22014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 03/12/2016] [Accepted: 03/12/2016] [Indexed: 06/05/2023]
Abstract
Bacterial mutation assays are conducted routinely as part of the safety assessment of new chemicals. The OECD Test Guideline (TG) 471 describes the conduct of the standard agar plate Ames assay, required for regulatory submissions. Higher throughput non-OECD 471 TG assays, such as the miniaturized plate incorporation and Ames II™ assays, can be used for prescreening purposes. We have compiled historical vehicle and positive control data generated using these methods. The historical database is comprised from experiments spanning 9 years and includes >1000 experiments from the standard Ames assay using the plate incorporation and pre-incubation methods (TA98, TA100, TA1535, TA1537, and WP2 uvrA), >50 experiments from the 6-well (TA98, TA100, TA1535, TA97a, and WP2 uvrA) and >100 experiments from the 24-well (TA98, TA100, TA102, TA1535, TA1537, and TA97a) plate incorporation assays, and >1000 experiments from the Ames II™ assay (TA98 and TAMix). Although miniaturization to a 24-well format made the measurement of control revertant colonies in TA1537 and TA1535 more difficult; this can be overcome by using an alternative strain with a higher spontaneous reversion rate (i.e., using TA97a instead of TA1537) or by increasing the number of replicate wells to 12 (for TA1535). All three miniaturized methods, including the Ames II™ assay, were responsive to known mutagens and the responses were reproducible over years of use. These data demonstrate the excellent reproducibility of the standard and miniaturized bacterial mutation assays using positive control chemicals. Environ. Mol. Mutagen. 57:483-496, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | | | - Jamie Sly
- BioReliance by SAFC, Rockville, Maryland
| | | | | | - Mark Cecil
- BioReliance by SAFC, Rockville, Maryland
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Obringer C, Manwaring J, Goebel C, Hewitt NJ, Rothe H. Suitability of the in vitro Caco-2 assay to predict the oral absorption of aromatic amine hair dyes. Toxicol In Vitro 2015; 32:1-7. [PMID: 26578466 DOI: 10.1016/j.tiv.2015.11.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/20/2015] [Accepted: 11/11/2015] [Indexed: 11/26/2022]
Abstract
Oral absorption is a key element for safety assessments of cosmetic ingredients, including hair dye molecules. Reliable in vitro methods are needed since the European Union has banned the use of animals for the testing of cosmetic ingredients. Caco-2 cells were used to measure the intestinal permeability characteristics (Papp) of 14 aromatic amine hair dye molecules with varying chemical structures, and the data were compared with historical in vivo oral absorption rat data. The majority of the hair dyes exhibited Papp values that indicated good in vivo absorption. The moderate to high oral absorption findings, i.e. ≥60%, were confirmed in in vivo rat studies. Moreover, the compound with a very low Papp value (APB: 3-((9,10-dihydro-9,10-dioxo-4-(methylamino)-1-anthracenyl)amino)-N,N-dimethyl-N-propyl-1-propanaminium) was poorly absorbed in vivo as well (5% of the dose). This data set suggests that the Caco-2 cell model is a reliable in vitro tool for the determination of the intestinal absorption of aromatic amines with diverse chemical structures. When used in combination with other in vitro assays for metabolism and skin penetration, the Caco-2 model can contribute to the prediction and mechanistic interpretation of the absorption, metabolism and elimination properties of cosmetic ingredients without the use of animals.
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Affiliation(s)
| | | | | | | | - Helga Rothe
- Procter & Gamble Service GmbH, Schwalbach, Germany
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Ramachandran SD, Vivarès A, Klieber S, Hewitt NJ, Muenst B, Heinz S, Walles H, Braspenning J. Applicability of second-generation upcyte® human hepatocytes for use in CYP inhibition and induction studies. Pharmacol Res Perspect 2015; 3:e00161. [PMID: 26516577 PMCID: PMC4618636 DOI: 10.1002/prp2.161] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 06/08/2015] [Indexed: 11/08/2022] Open
Abstract
Human upcyte® hepatocytes are proliferating hepatocytes that retain many characteristics of primary human hepatocytes. We conducted a comprehensive evaluation of the application of second-generation upcyte® hepatocytes from four donors for inhibition and induction assays using a selection of reference inhibitors and inducers. CYP1A2, CYP2B6, CYP2C9, and CYP3A4 were reproducibly inhibited in a concentration-dependent manner and the calculated IC50 values for each compound correctly classified them as potent inhibitors. Upcyte® hepatocytes were responsive to prototypical CYP1A2, CYP2B6, CYP2C9, and CYP3A4 inducers, confirming that they have functional AhR-, CAR-, and PXR-mediated CYP regulation. A panel of 11 inducers classified as potent, moderate or noninducers of CYP3A4 and CYP2B6 were tested. There was a good fit of data from upcyte® hepatocytes to three different predictive models for CYP3A4 induction, namely the Relative Induction Score (RIS), AUCu/F2, and C max,u/Ind50. In addition, PXR (rifampicin) and CAR-selective (carbamazepine and phenytoin) inducers of CYP3A4 and CYP2B6 induction, respectively, were demonstrated. In conclusion, these data support the use of second-generation upcyte® hepatocytes for CYP inhibition and induction assays. Under the culture conditions used, these cells expressed CYP activities that were equivalent to or higher than those measured in primary human hepatocyte cultures, which could be inhibited or induced by prototypical CYP inhibitors and inducers, respectively. Moreover, they can be used to predict in vivo CYP3A4 induction potential using three prediction models. Bulk availability of cells from multiple donors makes upcyte® hepatocytes suitable for DDI screening, as well as more in-depth mechanistic investigations.
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Affiliation(s)
| | - Aurélie Vivarès
- Sanofi – DSAR Drug Disposition – In Vitro models371, rue du Pr. Blayac, Montpellier, 34000, France
| | - Sylvie Klieber
- Sanofi – DSAR Drug Disposition – In Vitro models371, rue du Pr. Blayac, Montpellier, 34000, France
| | | | - Bernhard Muenst
- Medicyte GmbHIm Neuenheimer Feld 581, Heidelberg, D-69120, Germany
| | - Stefan Heinz
- Medicyte GmbHIm Neuenheimer Feld 581, Heidelberg, D-69120, Germany
| | - Heike Walles
- Tissue Engineering and Regenerative Medicine, University WuerzburgRoentgenring 11, Wuerzburg, D-97070, Germany
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Manwaring J, Rothe H, Obringer C, Foltz DJ, Baker TR, Troutman JA, Hewitt NJ, Goebel C. Extrapolation of systemic bioavailability assessing skin absorption and epidermal and hepatic metabolism of aromatic amine hair dyes in vitro. Toxicol Appl Pharmacol 2015; 287:139-148. [DOI: 10.1016/j.taap.2015.05.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 05/07/2015] [Accepted: 05/19/2015] [Indexed: 01/20/2023]
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Abstract
The use of cryopreserved hepatocytes has increased in the last decade due to the improvement of the freezing and thawing methods, and has even achieved acceptance by the US Food and Drug Administration for use in drug metabolizing enzyme induction studies. This chapter provides an overview of the theories behind the process of cryopreservation as well as practical advice on methods to cryopreserve hepatocytes, which retain functions similar to fresh cells after thawing. Parameters, such as cell density, cryoprotectants, freezing media, storage conditions, and thawing techniques, should be critically considered. Special emphasis is put on human hepatocytes, but information for the cryopreservation of animal hepatocytes is also described.
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Wiegand C, Hewitt NJ, Merk HF, Reisinger K. Dermal Xenobiotic Metabolism: A Comparison between Native Human Skin, Four in vitro Skin Test Systems and a Liver System. Skin Pharmacol Physiol 2014; 27:263-75. [DOI: 10.1159/000358272] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 12/30/2013] [Indexed: 11/19/2022]
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Hoppe E, Hewitt NJ, Buchstaller HP, Eggenweiler HM, Sirrenberg C, Zimmermann A, März J, Schwartz H, Saal C, Meyring M, Hecht S. A Novel Strategy for ADME Screening of Prodrugs: Combined Use of Serum and Hepatocytes to Integrate Bioactivation and Clearance, and Predict Exposure to Both Active and Prodrug to the Systemic Circulation. J Pharm Sci 2014; 103:1504-14. [DOI: 10.1002/jps.23942] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 02/18/2014] [Accepted: 02/21/2014] [Indexed: 11/09/2022]
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Nörenberg A, Heinz S, Scheller K, Hewitt NJ, Braspenning J, Ott M. Optimization of upcyte® human hepatocytes for the in vitro micronucleus assay. Mutat Res 2013; 758:69-79. [PMID: 24140631 DOI: 10.1016/j.mrgentox.2013.09.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 09/05/2013] [Accepted: 09/28/2013] [Indexed: 11/17/2022]
Abstract
"Upcyte(®) human hepatocytes" have the unique property of combining proliferation with the expression of drug metabolising activities. In our current study, we evaluated whether these cells would be suitable for early in vitro micronucleus (MN) tests. A treatment period of 96 h without a recovery period was most reliable for detecting MN formation in upcyte(®) hepatocytes from Donor 740. The basal MN rate in upcyte(®) hepatocytes varied considerably between donors (7-28%); therefore, modifications to the assay medium were tested to determine whether they could decrease inherent MN formation. Optimal medium supplements were 10 ng/ml oncostatin M for the pre-culture and recovery periods and 25 ng/ml epidermal growth factor and 10 ng/ml oncostatin M for the treatment period. Using the optimised conditions and outcome criteria, the upcyte(®) hepatocyte MN assay could correctly identify directly acting (e.g. mitomycin C, etoposide) and metabolically activated genotoxins (e.g. benzo[a]pyrene, cyclophosphamide). "True negative" and "false positive" compounds were also correctly identified as negative. The basal %MN in upcyte(®) hepatocytes from Donor 740 treated with DMSO, cyclophosphamide or MMC, was essentially unaffected by the growth stage ranging from population doublings of 14-61, suggesting that billions of cells could be produced from a single donor for standardised drug toxicity testing. In conclusion, we have established and optimised an in vitro MN test by using upcyte(®) hepatocytes to correctly identify known direct and metabolically activated genotoxicants as well as "false positives" and true negative compounds. The almost unlimited supply of cells from a single donor and optimised test conditions increase reproducibility in early and more predictive in vitro MN tests.
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Godoy P, Hewitt NJ, Albrecht U, Andersen ME, Ansari N, Bhattacharya S, Bode JG, Bolleyn J, Borner C, Böttger J, Braeuning A, Budinsky RA, Burkhardt B, Cameron NR, Camussi G, Cho CS, Choi YJ, Craig Rowlands J, Dahmen U, Damm G, Dirsch O, Donato MT, Dong J, Dooley S, Drasdo D, Eakins R, Ferreira KS, Fonsato V, Fraczek J, Gebhardt R, Gibson A, Glanemann M, Goldring CEP, Gómez-Lechón MJ, Groothuis GMM, Gustavsson L, Guyot C, Hallifax D, Hammad S, Hayward A, Häussinger D, Hellerbrand C, Hewitt P, Hoehme S, Holzhütter HG, Houston JB, Hrach J, Ito K, Jaeschke H, Keitel V, Kelm JM, Kevin Park B, Kordes C, Kullak-Ublick GA, LeCluyse EL, Lu P, Luebke-Wheeler J, Lutz A, Maltman DJ, Matz-Soja M, McMullen P, Merfort I, Messner S, Meyer C, Mwinyi J, Naisbitt DJ, Nussler AK, Olinga P, Pampaloni F, Pi J, Pluta L, Przyborski SA, Ramachandran A, Rogiers V, Rowe C, Schelcher C, Schmich K, Schwarz M, Singh B, Stelzer EHK, Stieger B, Stöber R, Sugiyama Y, Tetta C, Thasler WE, Vanhaecke T, Vinken M, Weiss TS, Widera A, Woods CG, Xu JJ, Yarborough KM, Hengstler JG. Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME. Arch Toxicol 2013; 87:1315-530. [PMID: 23974980 PMCID: PMC3753504 DOI: 10.1007/s00204-013-1078-5] [Citation(s) in RCA: 1042] [Impact Index Per Article: 94.7] [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: 05/02/2013] [Accepted: 05/06/2013] [Indexed: 12/15/2022]
Abstract
This review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways. When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes. An understanding of these changes is crucial for a correct interpretation of in vitro data. The possibilities and limitations of the most useful liver in vitro systems are summarized, including three-dimensional culture techniques, co-cultures with non-parenchymal cells, hepatospheres, precision cut liver slices and the isolated perfused liver. Also discussed is how closely hepatoma, stem cell and iPS cell-derived hepatocyte-like-cells resemble real hepatocytes. Finally, a summary is given of the state of the art of liver in vitro and mathematical modeling systems that are currently used in the pharmaceutical industry with an emphasis on drug metabolism, prediction of clearance, drug interaction, transporter studies and hepatotoxicity. One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation. Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.
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Affiliation(s)
- Patricio Godoy
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
| | | | - Ute Albrecht
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Melvin E. Andersen
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Nariman Ansari
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Sudin Bhattacharya
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Johannes Georg Bode
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Jennifer Bolleyn
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Christoph Borner
- Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
| | - Jan Böttger
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Albert Braeuning
- Department of Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Wilhelmstr. 56, 72074 Tübingen, Germany
| | - Robert A. Budinsky
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI USA
| | - Britta Burkhardt
- BG Trauma Center, Siegfried Weller Institut, Eberhard Karls University Tübingen, 72076 Tübingen, Germany
| | - Neil R. Cameron
- Department of Chemistry, Durham University, Durham, DH1 3LE UK
| | - Giovanni Camussi
- Department of Medical Sciences, University of Torino, 10126 Turin, Italy
| | - Chong-Su Cho
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Korea
| | - Yun-Jaie Choi
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Korea
| | - J. Craig Rowlands
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI USA
| | - Uta Dahmen
- Experimental Transplantation Surgery, Department of General Visceral, and Vascular Surgery, Friedrich-Schiller-University Jena, 07745 Jena, Germany
| | - Georg Damm
- Department of General-, Visceral- and Transplantation Surgery, Charité University Medicine Berlin, 13353 Berlin, Germany
| | - Olaf Dirsch
- Institute of Pathology, Friedrich-Schiller-University Jena, 07745 Jena, Germany
| | - María Teresa Donato
- Unidad de Hepatología Experimental, IIS Hospital La Fe Avda Campanar 21, 46009 Valencia, Spain
- CIBERehd, Fondo de Investigaciones Sanitarias, Barcelona, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valencia, Valencia, Spain
| | - Jian Dong
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Steven Dooley
- Department of Medicine II, Section Molecular Hepatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Dirk Drasdo
- Interdisciplinary Center for Bioinformatics (IZBI), University of Leipzig, 04107 Leipzig, Germany
- INRIA (French National Institute for Research in Computer Science and Control), Domaine de Voluceau-Rocquencourt, B.P. 105, 78153 Le Chesnay Cedex, France
- UPMC University of Paris 06, CNRS UMR 7598, Laboratoire Jacques-Louis Lions, 4, pl. Jussieu, 75252 Paris cedex 05, France
| | - Rowena Eakins
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Karine Sá Ferreira
- Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
- GRK 1104 From Cells to Organs, Molecular Mechanisms of Organogenesis, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Valentina Fonsato
- Department of Medical Sciences, University of Torino, 10126 Turin, Italy
| | - Joanna Fraczek
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Andrew Gibson
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Matthias Glanemann
- Department of General-, Visceral- and Transplantation Surgery, Charité University Medicine Berlin, 13353 Berlin, Germany
| | - Chris E. P. Goldring
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - María José Gómez-Lechón
- Unidad de Hepatología Experimental, IIS Hospital La Fe Avda Campanar 21, 46009 Valencia, Spain
- CIBERehd, Fondo de Investigaciones Sanitarias, Barcelona, Spain
| | - Geny M. M. Groothuis
- Department of Pharmacy, Pharmacokinetics Toxicology and Targeting, University of Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Lena Gustavsson
- Department of Laboratory Medicine (Malmö), Center for Molecular Pathology, Lund University, Jan Waldenströms gata 59, 205 02 Malmö, Sweden
| | - Christelle Guyot
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - David Hallifax
- Centre for Applied Pharmacokinetic Research (CAPKR), School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT UK
| | - Seddik Hammad
- Department of Forensic Medicine and Veterinary Toxicology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt
| | - Adam Hayward
- Biological and Biomedical Sciences, Durham University, Durham, DH13LE UK
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Claus Hellerbrand
- Department of Medicine I, University Hospital Regensburg, 93053 Regensburg, Germany
| | | | - Stefan Hoehme
- Interdisciplinary Center for Bioinformatics (IZBI), University of Leipzig, 04107 Leipzig, Germany
| | - Hermann-Georg Holzhütter
- Institut für Biochemie Abteilung Mathematische Systembiochemie, Universitätsmedizin Berlin (Charité), Charitéplatz 1, 10117 Berlin, Germany
| | - J. Brian Houston
- Centre for Applied Pharmacokinetic Research (CAPKR), School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT UK
| | | | - Kiyomi Ito
- Research Institute of Pharmaceutical Sciences, Musashino University, 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo, 202-8585 Japan
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160 USA
| | - Verena Keitel
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | | | - B. Kevin Park
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Claus Kordes
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Gerd A. Kullak-Ublick
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - Edward L. LeCluyse
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Peng Lu
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | | | - Anna Lutz
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Freiburg, Germany
| | - Daniel J. Maltman
- Reinnervate Limited, NETPark Incubator, Thomas Wright Way, Sedgefield, TS21 3FD UK
| | - Madlen Matz-Soja
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Patrick McMullen
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Irmgard Merfort
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Freiburg, Germany
| | | | - Christoph Meyer
- Department of Medicine II, Section Molecular Hepatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Jessica Mwinyi
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - Dean J. Naisbitt
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Andreas K. Nussler
- BG Trauma Center, Siegfried Weller Institut, Eberhard Karls University Tübingen, 72076 Tübingen, Germany
| | - Peter Olinga
- Division of Pharmaceutical Technology and Biopharmacy, Department of Pharmacy, University of Groningen, 9713 AV Groningen, The Netherlands
| | - Francesco Pampaloni
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Jingbo Pi
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Linda Pluta
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Stefan A. Przyborski
- Reinnervate Limited, NETPark Incubator, Thomas Wright Way, Sedgefield, TS21 3FD UK
- Biological and Biomedical Sciences, Durham University, Durham, DH13LE UK
| | - Anup Ramachandran
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160 USA
| | - Vera Rogiers
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Cliff Rowe
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Celine Schelcher
- Department of Surgery, Liver Regeneration, Core Facility, Human in Vitro Models of the Liver, Ludwig Maximilians University of Munich, Munich, Germany
| | - Kathrin Schmich
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Freiburg, Germany
| | - Michael Schwarz
- Department of Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Wilhelmstr. 56, 72074 Tübingen, Germany
| | - Bijay Singh
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Korea
| | - Ernst H. K. Stelzer
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Bruno Stieger
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - Regina Stöber
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
| | - Yuichi Sugiyama
- Sugiyama Laboratory, RIKEN Innovation Center, RIKEN, Yokohama Biopharmaceutical R&D Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Ciro Tetta
- Fresenius Medical Care, Bad Homburg, Germany
| | - Wolfgang E. Thasler
- Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich, Germany
| | - Tamara Vanhaecke
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Mathieu Vinken
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Thomas S. Weiss
- Department of Pediatrics and Juvenile Medicine, University of Regensburg Hospital, Regensburg, Germany
| | - Agata Widera
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
| | - Courtney G. Woods
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | | | | | - Jan G. Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
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Hewitt NJ, Edwards RJ, Fritsche E, Goebel C, Aeby P, Scheel J, Reisinger K, Ouédraogo G, Duche D, Eilstein J, Latil A, Kenny J, Moore C, Kuehnl J, Barroso J, Fautz R, Pfuhler S. Use of Human In Vitro Skin Models for Accurate and Ethical Risk Assessment: Metabolic Considerations. Toxicol Sci 2013; 133:209-17. [DOI: 10.1093/toxsci/kft080] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Burkard A, Dähn C, Heinz S, Zutavern A, Sonntag-Buck V, Maltman D, Przyborski S, Hewitt NJ, Braspenning J. Generation of proliferating human hepatocytes using Upcyte® technology: characterisation and applications in induction and cytotoxicity assays. Xenobiotica 2012; 42:939-56. [PMID: 22524704 DOI: 10.3109/00498254.2012.675093] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
1. We have developed a novel technique which causes primary human hepatocytes to proliferate by transducing them with genes that upregulate their proliferation. 2. Upcyte(®) hepatocytes did not form colonies in soft agar and are not immortalised anchorage-independent cells. Confluent cultures expressed liver-specific proteins, produced urea and stored glycogen. 3. CYP activities were low but similar to that in 5-day cultures of primary human hepatocytes. CYP1A2 and CYP3A4 were inducible; moreover, upcyte(®) hepatocytes predicted the in vivo induction potencies of known CYP3A4 inducers using the "relative induction score" prediction model. Placing cells into 3D culture increased their basal CYP2B6 and CYP3A4 basal activities and induction responses. 4. Phase 2 activities (UGTs, SULTs and GSTs) were comparable to activities in freshly isolated hepatocytes. 5. Upcyte(®) hepatocytes were markedly more sensitive to the hepatotoxin, α-amanitin, than HepG2 cells, indicating functional OATP1B3 uptake. The cytotoxicity of aflatoxin B(1), was decreased in upcyte(®) hepatocytes by co-incubation with the CYP3A4 inhibitor, ketoconazole. Upcyte(®) hepatocytes also differentiated between ten hepatotoxic and eight non-hepatotoxic compounds. 6. In conclusion, upcyte(®) hepatocyte cultures have a differentiated phenotype and exhibit functional phase 1 and 2 activities. These data support the use of upcyte(®) hepatocytes for CYP induction and cytotoxicity screening.
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Götz C, Hewitt NJ, Jermann E, Tigges J, Kohne Z, Hübenthal U, Krutmann J, Merk HF, Fritsche E. Effects of the genotoxic compounds, benzo[a]pyrene and cyclophosphamide on phase 1 and 2 activities in EpiDerm™ models. Xenobiotica 2011; 42:526-37. [DOI: 10.3109/00498254.2011.643255] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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49
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Dahl EL, Curren R, Barnett BC, Khambatta Z, Reisinger K, Ouedraogo G, Faquet B, Ginestet AC, Mun G, Hewitt NJ, Carr G, Pfuhler S, Aardema MJ. The reconstructed skin micronucleus assay (RSMN) in EpiDerm™: Detailed protocol and harmonized scoring atlas. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2011; 720:42-52. [DOI: 10.1016/j.mrgentox.2010.12.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 12/02/2010] [Indexed: 11/17/2022]
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Pfuhler S, Kirst A, Aardema M, Banduhn N, Goebel C, Araki D, Costabel-Farkas M, Dufour E, Fautz R, Harvey J, Hewitt NJ, Hibatallah J, Carmichael P, Macfarlane M, Reisinger K, Rowland J, Schellauf F, Schepky A, Scheel J. Corrigendum to ‘A tiered approach to the use of alternatives to animal testing for the safety assessment of cosmetics: Genotoxicity. A COLIPA analysis’ [Regulatory Toxicology and Pharmacology 57 (2010) 315–324]. Regul Toxicol Pharmacol 2010. [DOI: 10.1016/j.yrtph.2010.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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