1
|
Lagadic L, Coady KK, Körner O, Miller TJ, Mingo V, Salinas ER, Sauer UG, Schopfer CR, Weltje L, Wheeler JR. Endocrine disruption assessment in aquatic vertebrates - Identification of substance-induced thyroid-mediated effect patterns. ENVIRONMENT INTERNATIONAL 2024; 191:108918. [PMID: 39270431 DOI: 10.1016/j.envint.2024.108918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 07/12/2024] [Accepted: 07/26/2024] [Indexed: 09/15/2024]
Abstract
According to the World Health Organisation and European Commission definitions, substances shall be considered as having endocrine disrupting properties if they show adverse effects, have endocrine activity and the adverse effects are a consequence of the endocrine activity (using a weight-of-evidence approach based on biological plausibility), unless the adverse effects are not relevant to humans or non-target organisms at the (sub)population level. To date, there is no decision logic on how to establish endocrine disruption via the thyroid modality in non-mammalian vertebrates. This paper describes an evidence-based decision logic compliant with the integrated approach to testing and assessment (IATA) concept, to identify thyroid-mediated effect patterns in aquatic vertebrates using amphibians as relevant models for thyroid disruption assessment. The decision logic includes existing test guidelines and methods and proposes detailed considerations on how to select relevant assays and interpret the findings. If the mammalian dataset used as the starting point indicates no thyroid concern, the Xenopus Eleutheroembryonic Thyroid Assay allows checking out thyroid-mediated activity in non-mammalian vertebrates, whereas the Amphibian Metamorphosis Assay or its extended, fixed termination stage variant inform on both thyroid-mediated activity and potentially population-relevant adversity. In evaluating findings, the response patterns of all assay endpoints are considered, including the direction of changes. Thyroid-mediated effect patterns identified at the individual level in the amphibian tests are followed by mode-of-action and population relevance assessments. Finally, all data are considered in an overarching weight-of-evidence evaluation. The logic has been designed generically and can be adapted, e.g. to accommodate fish tests once available for thyroid disruption assessments. It also ensures that all scientifically relevant information is considered, and that animal testing is minimised. The proposed decision logic can be included in regulatory assessments to facilitate the conclusion on whether substances meet the endocrine disruptor definition for the thyroid modality in non-mammalian vertebrates.
Collapse
Affiliation(s)
- Laurent Lagadic
- Bayer AG - R&D, Crop Science Division, Environmental Safety, Monheim, Germany.
| | | | - Oliver Körner
- ADAMA Deutschland GmbH, Environmental Safety, Köln, Germany
| | - Tara J Miller
- Syngenta, Jealott's Hill International Research Centre, Jealott's Hill, United Kingdom
| | | | - Edward R Salinas
- Bayer AG - R&D, Crop Science Division, Environmental Safety, Monheim, Germany
| | - Ursula G Sauer
- Scientific Consultancy - Animal Welfare, Neubiberg, Germany
| | | | - Lennart Weltje
- BASF SE, Agricultural Solutions - Ecotoxicology, Limburgerhof, Germany; Georg-August-University Göttingen, Division of Plant Pathology and Plant Protection, Göttingen, Germany
| | | |
Collapse
|
2
|
Manera M, Giari L. Segmentation of Renal Thyroid Follicle Colloid in Common Carp: Insights into Perfluorooctanoic Acid-Induced Morphometric Alterations. TOXICS 2024; 12:369. [PMID: 38787148 PMCID: PMC11126022 DOI: 10.3390/toxics12050369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/12/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
Perfluorooctanoic acid (PFOA) is a globally prevalent contaminant of concern recognised for its persistence and detrimental effects on both wildlife and humans. While PFOA has been established as a disruptor of thyroid function, limited data exist regarding its impact on thyroid morphology. The kidney of the common carp (Cyprinus carpio) harbours numerous thyroid follicles, rendering it a valuable biomarker organ for investigating PFOA-induced thyroid alterations. Renal tissue slides, stained with the Alcian blue/PAS method, were examined from carp in three experimental groups: unexposed, exposed to 200 ng L-1, and exposed to 2 mg L-1 of PFOA over 56 days. Thyroid follicle colloids were segmented, and related morphometric parameters, including perimeter, area, and shape descriptors, were obtained. Statistical analyses revealed significant reductions in thyroid follicle colloid perimeter and area in the 200 ng L-1 PFOA group compared to the unexposed and 2 mg L-1 PFOA groups. Additionally, the fish exposed to PFOA exhibited a significantly higher follicle count compared to the unexposed fish. These findings collectively suggest that PFOA induces thyroid folliculogenesis, emphasising its impact on thyroid morphology even at an environmentally relevant concentration (200 ng L-1).
Collapse
Affiliation(s)
- Maurizio Manera
- Department of Biosciences, Food and Environmental Technologies, University of Teramo, St. R. Balzarini 1, 64100 Teramo, Italy
| | - Luisa Giari
- Department of Environmental and Prevention Sciences, University of Ferrara, St. L. Borsari 46, 44121 Ferrara, Italy;
| |
Collapse
|
3
|
Kadic A, Oles P, Fischer BC, Reetz AE, Sylla BS, Feiertag K, Ritz V, Heise T, Marx-Stoelting P, Tralau T, Renko K, Solano MDLM. In vitro and in vivo investigation of a thyroid hormone system-specific interaction with triazoles. Sci Rep 2024; 14:6503. [PMID: 38499550 PMCID: PMC10948911 DOI: 10.1038/s41598-024-55019-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 02/19/2024] [Indexed: 03/20/2024] Open
Abstract
Alterations in thyroid hormones (TH) and thyroid-stimulating hormone levels are frequently found following exposure to chemicals of concern. Dysregulation of TH levels can severely perturb physiological growth, metabolism, differentiation, homeostasis in the adult and developmental processes in utero. A frequently identified mode of action for this interaction is the induction of hepatic detoxification mechanisms (e.g. SULTs and UGTs), which lead to TH conjugation and elimination and therefore interfere with hormonal homeostasis, fulfilling the endocrine disruptors (EDs) definition. A short-term study in rats with dietary exposure to cyproconazole, epoxiconazole and prochloraz was conducted and hepatocyte hypertrophy, hepatic UGT activity and Phase 1/2 gene expression inductions were observed together with changes in TH levels and thyroid follicular hypertrophy and hyperplasia. To test for specific interaction with the thyroid hormone system, in vitro assays were conducted covering thyroidal I-uptake (NIS), TH transmembranal transport via MCT8 and thyroid peroxidase (TPO) function. Assays for iodothyronine deiodinases (DIO1-DIO3) and iodotyrosine deiodinase (DEHAL1) were included, and from the animal experiment, Dio1 and Dehal1 activities were measured in kidney and liver as relevant local indicators and endpoints. The fungicides did not affect any TH-specific KEs, in vitro and in vivo, thereby suggesting hepatic conjugation as the dominant MoA.
Collapse
Affiliation(s)
- Asya Kadic
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Patricia Oles
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277, Berlin, Germany
| | - Benjamin Christian Fischer
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Anne Elisabeth Reetz
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
- Institute of Veterinary Pathology (WE12), Freie University Berlin, Berlin, Germany
| | - Boubacar Sidiki Sylla
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Katreece Feiertag
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Vera Ritz
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Tanja Heise
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Philip Marx-Stoelting
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Tewes Tralau
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Kostja Renko
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277, Berlin, Germany.
| | - Marize de Lourdes Marzo Solano
- Department of Pesticides Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany.
| |
Collapse
|
4
|
Tammaro A, Lori G, Martinelli A, Cancemi L, Tassinari R, Maranghi F. Risk assessment of transgender people: implementation of a demasculinizing-feminizing rodent model including the evaluation of thyroid homeostasis. Biol Direct 2024; 19:5. [PMID: 38166984 PMCID: PMC10759629 DOI: 10.1186/s13062-023-00450-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 12/20/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Individuals whose gender identity differs from the biological sex and the social norms are defined as transgender. Sometimes transgender undergo gender affirming hormone therapy, which lasts for the entire life making essential to evaluate its potential long-term effects. Moreover, transgender can represent a susceptible sub-group of population and specific attention is needed in risk assessment, including the development of targeted animal models. Aim of the study is the implementation of a rodent demasculinizing-feminizing model through the setting of appropriate dose of hormone therapy and the selection of specific biomarkers to evaluate the sex transition. Specific attention is paid to thyroid homeostasis due to the close link with reproductive functions. Four male adult rats/group were subcutaneously exposed to three doses plus control of β-estradiol valerate plus cyproterone acetate at: 0.045 + 0.2 (low), 0.09 + 0.2 (medium) and 0.18 + 0.2 (high) mg/dose, five times/week. The doses were selected considering the most recent recommendations for transgender woman. Sperm count, histopathological analysis (testis, liver, thyroid), testosterone, estradiol, triiodothyronine and thyroid-stimulating hormone serum levels and gene expression of sex dimorphic CYP450 were evaluated. RESULTS The doses induced feminizing-demasculinizing effects: decreased testosterone serum levels at the corresponding cisgender, increased estradiol, impairment of male reproductive function and reversal of sex-specific CYP liver expression. However, the medium and high doses induced marked liver toxicity and the low dose is considered the best choice, also for long-term studies in risk assessment. The alterations of thyroid indicated follicular cell hypertrophy supported by increased thyroid-stimulating hormone serum levels at the higher doses. CONCLUSIONS The implementation of animal models that mimic the effects of gender affirming hormone therapy is essential for supporting clinical studies in transgender people and filling data gap in order to ensure an appropriate risk assessment and a more accurate, personalized care for transgender people.
Collapse
Affiliation(s)
- Alessia Tammaro
- Center for Gender-Specific Medicine, Istituto Superiore di Sanità, Rome, Italy
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Gabriele Lori
- Center for Gender-Specific Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Andrea Martinelli
- Experimental Animal Welfare Sector, Istituto Superiore di Sanità, Rome, Italy
| | - Luigia Cancemi
- Experimental Animal Welfare Sector, Istituto Superiore di Sanità, Rome, Italy
| | - Roberta Tassinari
- Center for Gender-Specific Medicine, Istituto Superiore di Sanità, Rome, Italy.
| | - Francesca Maranghi
- Center for Gender-Specific Medicine, Istituto Superiore di Sanità, Rome, Italy
| |
Collapse
|
5
|
Eytcheson SA, Olker JH, Friedman KP, Hornung MW, Degitz SJ. Assessing utility of thyroid in vitro screening assays through comparisons to observed impacts in vivo. Regul Toxicol Pharmacol 2023; 144:105491. [PMID: 37666444 DOI: 10.1016/j.yrtph.2023.105491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 08/22/2023] [Accepted: 08/30/2023] [Indexed: 09/06/2023]
Abstract
To better understand endocrine disruption, the U.S. Environmental Protection Agency's (USEPA) Endocrine Disruptor Screening Program (EDSP) utilizes a two-tiered approach to investigate the potential of a chemical to interact with the estrogen, androgen, or thyroid systems. As in vivo testing lacks the throughput to address data gaps on endocrine bioactivity for thousands of chemicals, in vitro high-throughput screening (HTS) methods are being developed to screen larger chemical libraries. The primary objective of this work was to investigate for how many of the 52 chemicals with weight-of-evidence (WoE) determinations from EDSP Tier 1 screening there are available in vitro HTS data supporting a thyroid impact. HTS data from the USEPA ToxCast program and the EDSP WoE were collected for this analysis. Considering the complexity of endocrine disruption and interpreting HTS data, concordance between in vitro activity and in vivo effects ranges from 58 to 78%. Based on this evaluation, we conclude that the current suite of HTS assays is beneficial for prioritizing chemicals for further inquiry; however, without a more detailed analysis, one cannot conclude whether HTS results are the primary mode-of-action. Furthermore, development of in vitro assays for additional thyroid-relevant molecular initiating events is required to effectively predict in vivo thyroid impacts.
Collapse
Affiliation(s)
- Stephanie A Eytcheson
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA; U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, Duluth, MN, 55804, USA
| | - Jennifer H Olker
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, Duluth, MN, 55804, USA
| | - Katie Paul Friedman
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Biomolecular and Computational Toxicology Division, Research Triangle Park, NC, 27711, USA
| | - Michael W Hornung
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, Duluth, MN, 55804, USA
| | - Sigmund J Degitz
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, Duluth, MN, 55804, USA.
| |
Collapse
|
6
|
Tallon MJ, Child R. Subchronic oral toxicity assessment of a cannabis extract. Regul Toxicol Pharmacol 2023; 144:105496. [PMID: 37734651 DOI: 10.1016/j.yrtph.2023.105496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 09/10/2023] [Accepted: 09/13/2023] [Indexed: 09/23/2023]
Abstract
Cannabidiol (CBD) is present in Cannabis Sativa L. and has been used in medicines and foods to deliver beneficial health effects. Despite this, research on CBD safety utilising modern testing methods is lacking. Therefore three separate safety experiments were performed on a CBD isolate. Sprague-Dawley rats were used to investigate prenatal development, a 14-day toxicity sighting study, and an OECD compliant 90-day subchronic oral toxicity trial, with 35-day off-dose recovery. The prenatal screening study demonstrated reduced body weights and food consumption in the highest dose group, but no substance-related changes in pregnancy rate, maternal or placental gross abnormalities, or premature deliveries. The 14-day study indicated tolerance up to 460 mg/kg bw/d of CBD isolate. Based on these findings, a 90-day repeated dose oral toxicity study was performed at doses of 0, 30, 115, 230, and 460 mg/kg bw/d of CBD, followed by a 35-day off-dose recovery period. In the 90-day study, some non-adverse organ and tissue changes were observed. With the exception of the high dose group, these fully reversed during the recovery period. Based on these findings, sub-chronic consumption of highly purified isolate results in a CBD NOAEL of 460 mg/kg bw/d for males and 230 mg/kg bw/d for females.
Collapse
Affiliation(s)
- Mark J Tallon
- Legal Products Group Ltd, 26 St Thomas Pl, Ely, Cambridgeshire, CB7 4EX, UK.
| | - Robert Child
- Legal Products Group Ltd, 26 St Thomas Pl, Ely, Cambridgeshire, CB7 4EX, UK; School of Chemical Engineering, University of Birmingham, Birmingham, B15 2TT, UK
| |
Collapse
|
7
|
Henderson RG, Welsh BT, Rogers JM, Borghoff SJ, Trexler KR, Bonn-Miller MO, Lefever TW. Reproductive and developmental toxicity evaluation of cannabidiol. Food Chem Toxicol 2023; 176:113786. [PMID: 37105390 DOI: 10.1016/j.fct.2023.113786] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023]
Abstract
An important data gap in determining a safe level of cannabidiol (CBD) intake for consumer use is determination of CBD's potential to cause reproductive or developmental toxicity. We conducted an OECD Test Guideline 421 GLP-compliant study in rats, with extended postnatal dosing and hormone analysis, where hemp-derived CBD isolate (0, 30, 100, or 300 mg/kg-bw/d) was administered orally. Treatment-related mortality, moribundity, and decreased body weight and food consumption were observed in high-dose F0 adult animals, consistent with severe maternal toxicity. No effects were observed on testosterone concentrations, F0 reproductive performance, or reproductive organs. Hepatocellular hypertrophy in the 100- and 300 mg/kg-bw/day groups correlated with hypertrophy/hyperplasia in the thyroid gland and changes in mean thyroid hormone concentrations in F0 animals. Mean gestation length was unaffected; however, total litter loss for two females and dystocia for two additional females in the high-dose group occurred. Other developmental effects were limited to lower mean pup weights in the 300 mg/kg-bw/d group than those of controls. The following NOAELs were identified for CBD isolate based on this study: 100 mg/kg-bw/d for F0 systemic toxicity and female reproductive toxicity, 300 mg/kg-bw/d for F0 male reproductive toxicity, and 100 mg/kg-bw/d for F1 neonatal and F1 generation toxicity.
Collapse
Affiliation(s)
| | | | - John M Rogers
- ToxStrategies, Inc., Research Triangle Park, NC, 27511, USA
| | | | | | | | | |
Collapse
|
8
|
Henderson RG, Lefever TW, Heintz MM, Trexler KR, Borghoff SJ, Bonn-Miller MO. Oral toxicity evaluation of cannabidiol. Food Chem Toxicol 2023; 176:113778. [PMID: 37105391 DOI: 10.1016/j.fct.2023.113778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/28/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023]
Abstract
Use of cannabidiol (CBD) in humans has increased considerably in recent years. While currently available studies suggest that CBD is relatively safe for human consumption, data from publicly available studies on CBD conducted according to modern testing guidelines are lacking. In the current study, the potential for toxicity following repeated oral exposure to hemp-derived CBD isolate was evaluated in male and female Sprague Dawley rats. No adverse treatment-related effects were observed following administration of CBD via oral gavage for 14 and 90 days at concentrations up to 150 and 140 mg/kg-bw/d, respectively. Microscopic liver and adrenal gland changes observed in the 90-day study were determined to be resolved after a 28-day recovery period. CBD was well tolerated at these dose levels, and the results of this study are comparable to findings reported in unpublished studies conducted with other CBD isolates. The current studies were conducted as part of a broader research program to examine the safety of CBD.
Collapse
|
9
|
Marty MS, Sauer UG, Charlton A, Ghaffari R, Guignard D, Hallmark N, Hannas BR, Jacobi S, Marxfeld HA, Melching-Kollmuss S, Sheets LP, Urbisch D, Botham PA, van Ravenzwaay B. Towards a science-based testing strategy to identify maternal thyroid hormone imbalance and neurodevelopmental effects in the progeny-part III: how is substance-mediated thyroid hormone imbalance in pregnant/lactating rats or their progeny related to neurodevelopmental effects? Crit Rev Toxicol 2022; 52:546-617. [PMID: 36519295 DOI: 10.1080/10408444.2022.2130166] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review investigated which patterns of thyroid- and brain-related effects are seen in rats upon gestational/lactational exposure to 14 substances causing thyroid hormone imbalance by four different modes-of-action (inhibition of thyroid peroxidase, sodium-iodide symporter and deiodinase activities, enhancement of thyroid hormone clearance) or to dietary iodine deficiency. Brain-related parameters included motor activity, cognitive function, acoustic startle response, hearing function, periventricular heterotopia, electrophysiology and brain gene expression. Specific modes-of-action were not related to specific patterns of brain-related effects. Based upon the rat data reviewed, maternal serum thyroid hormone levels do not show a causal relationship with statistically significant neurodevelopmental effects. Offspring serum thyroxine together with offspring serum triiodothyronine and thyroid stimulating hormone appear relevant to predict the likelihood for neurodevelopmental effects. Based upon the collated database, thresholds of ≥60%/≥50% offspring serum thyroxine reduction and ≥20% and statistically significant offspring serum triiodothyronine reduction indicate an increased likelihood for statistically significant neurodevelopmental effects; accuracies: 83% and 67% when excluding electrophysiology (and gene expression). Measurements of brain thyroid hormone levels are likely relevant, too. The extent of substance-mediated thyroid hormone imbalance appears more important than substance mode-of-action to predict neurodevelopmental impairment in rats. Pertinent research needs were identified, e.g. to determine whether the phenomenological offspring thyroid hormone thresholds are relevant for regulatory toxicity testing. The insight from this review shall be used to suggest a tiered testing strategy to determine whether gestational/lactational substance exposure may elicit thyroid hormone imbalance and potentially also neurodevelopmental effects.
Collapse
Affiliation(s)
| | - Ursula G Sauer
- Scientific Consultancy-Animal Welfare, Neubiberg, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Bertani V, Blanck O, Guignard D, Schorsch F, Pischon H. Artificial Intelligence in Toxicological Pathology: Quantitative Evaluation of Compound-Induced Follicular Cell Hypertrophy in Rat Thyroid Gland Using Deep Learning Models. Toxicol Pathol 2021; 50:23-34. [PMID: 34670459 DOI: 10.1177/01926233211052010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Digital pathology has recently been more broadly deployed, fueling artificial intelligence (AI) application development and more systematic use of image analysis. Here, two different AI models were developed to evaluate follicular cell hypertrophy in hematoxylin and eosin-stained whole-slide-images of rat thyroid gland, using commercial AI-based-software. In the first, mean cytoplasmic area measuring approach (MCA approach), mean cytoplasmic area was calculated via several sequential deep learning (DL)-based algorithms including segmentation in microanatomical structures (separation of colloid and stroma from thyroid follicular epithelium), nuclear detection, and area measurements. With our additional second, hypertrophy area fraction predicting approach (HAF approach), we present for the first time DL-based direct detection of the histopathological change follicular cell hypertrophy in the thyroid gland with similar results. For multiple studies, increased output parameters (mean cytoplasmic area and hypertrophic area fraction) were shown in groups given different hypertrophy-inducing reference compounds in comparison to control groups. Quantitative results correlated with the gold standard of board-certified veterinary pathologists' diagnoses and gradings as well as thyroid hormone dependent gene expressions. Accuracy and repeatability of diagnoses and grading by pathologists are expected to be improved by additional evaluation of mean cytoplasmic area or direct detection of hypertrophy, combined with standard histopathological observations.
Collapse
Affiliation(s)
| | - Olivier Blanck
- Bayer CropScience SAS, Sophia Antipolis, Valbonne, France
| | - Davy Guignard
- Bayer CropScience SAS, Sophia Antipolis, Valbonne, France
| | | | | |
Collapse
|
11
|
Marty S, Beekhuijzen M, Charlton A, Hallmark N, Hannas BR, Jacobi S, Melching-Kollmuss S, Sauer UG, Sheets LP, Strauss V, Urbisch D, Botham PA, van Ravenzwaay B. Towards a science-based testing strategy to identify maternal thyroid hormone imbalance and neurodevelopmental effects in the progeny - part II: how can key events of relevant adverse outcome pathways be addressed in toxicological assessments? Crit Rev Toxicol 2021; 51:328-358. [PMID: 34074207 DOI: 10.1080/10408444.2021.1910625] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The current understanding of thyroid-related adverse outcome pathways (AOPs) with adverse neurodevelopmental outcomes in mammals has been reviewed. This served to establish if standard rodent toxicity test methods and in vitro assays allow identifying thyroid-related modes-of-action potentially leading to adverse neurodevelopmental outcomes, and the human relevance of effects - in line with the European Commission's Endocrine Disruptor Criteria. The underlying hypothesis is that an understanding of the key events of relevant AOPs provides insight into differences in incidence, magnitude, or species sensitivity of adverse outcomes. The rodent studies include measurements of serum thyroid hormones, thyroid gland pathology and neurodevelopmental assessments, but do not directly inform on specific modes-of-action. Opportunities to address additional non-routine parameters reflecting critical events of AOPs in toxicological assessments are presented. These parameters appear relevant to support the identification of specific thyroid-related modes-of-action, provided that prevailing technical limitations are overcome. Current understanding of quantitative key event relationships is often weak, but would be needed to determine if the triggering of a molecular initiating event will ultimately result in an adverse outcome. Also, significant species differences in all processes related to thyroid hormone signalling are evident, but the biological implications thereof (including human relevance) are often unknown. In conclusion, careful consideration of the measurement (e.g. timing, method) and interpretation of additional non-routine parameters is warranted. These findings will be used in a subsequent paper to propose a testing strategy to identify if a substance may elicit maternal thyroid hormone imbalance and potentially also neurodevelopmental effects in the progeny.
Collapse
Affiliation(s)
- Sue Marty
- The Dow Chemical Company, Midland, MI, USA
| | | | | | | | | | | | | | - Ursula G Sauer
- Scientific Consultancy - Animal Welfare, Neubiberg, Germany
| | | | | | | | | | | |
Collapse
|
12
|
Rosol TJ, Witorsch RJ. Ethyl acrylate (EA) exposure and thyroid carcinogenicity in rats and mice with relevance to human health. Regul Toxicol Pharmacol 2021; 124:104961. [PMID: 34015422 DOI: 10.1016/j.yrtph.2021.104961] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 05/03/2021] [Accepted: 05/13/2021] [Indexed: 12/28/2022]
Abstract
Ethyl acrylate (EA) was classified by IARC as a Group-2B Carcinogen based, in part, on data suggesting increased incidence of thyroid neoplasia in rats and mice exposed chronically to EA vapors. We examined chronic exposure of rats and mice to EA vapors, evaluated the data on the incidence of thyroid follicular neoplasia, and determined the relevance of thyroid tumors to human health risk. The data revealed a small statistically significant increase in thyroid tumors in EA-exposed male rats and mice. The tumor incidences were within the range of historical controls and were not consistently dose-dependent. Most thyroid tumors in exposed animals were benign. Chronic exposure of EA to rats and mice (drinking water or gavage) and dogs (capsules) had no evidence of thyroid neoplasia. Results from chronic studies, in vivo and in vitro data, and ToxCastTM/Tox 21 HTPS did not support genotoxic/mutagenic potential for EA. This suggests that the associations between EA exposure and thyroid neoplasia represent chance or random observations rather than a compound-mediated effect. Due to species-specific physiological differences, the hypothalamic-pituitary-thyroid axis of rodents is more sensitive to endocrine disruptive chemicals than that of humans which further suggests that findings in rodents have questionable relevance to human health.
Collapse
Affiliation(s)
- Thomas J Rosol
- Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701, USA.
| | - Raphael J Witorsch
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA, 23298, USA.
| |
Collapse
|