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Zilliacus J, Draskau MK, Johansson HKL, Svingen T, Beronius A. Building an adverse outcome pathway network for estrogen-, androgen- and steroidogenesis-mediated reproductive toxicity. Front Toxicol 2024; 6:1357717. [PMID: 38601197 PMCID: PMC11005472 DOI: 10.3389/ftox.2024.1357717] [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: 12/18/2023] [Accepted: 03/11/2024] [Indexed: 04/12/2024] Open
Abstract
Introduction: Adverse Outcome Pathways (AOPs) can support both testing and assessment of endocrine disruptors (EDs). There is, however, a need for further development of the AOP framework to improve its applicability in a regulatory context. Here we have inventoried the AOP-wiki to identify all existing AOPs related to mammalian reproductive toxicity arising from disruption to the estrogen, androgen, and steroidogenesis modalities. Core key events (KEs) shared between relevant AOPs were also identified to aid in further AOP network (AOPN) development. Methods: A systematic approach using two different methods was applied to screen and search the entire AOP-wiki library. An AOPN was visualized using Cytoscape. Manual refinement was performed to remove AOPS devoid of any KEs and/or KERs. Results: Fifty-eight AOPs relevant for mammalian reproductive toxicity were originally identified, with 42 AOPs included in the final AOPN. Several of the KEs and KE relationships (KERs) described similar events and were thus merged to optimize AOPN construction. Sixteen sub-networks related to effects on hormone levels or hormone activity, cancer outcomes, male and female reproductive systems, and overall effects on fertility and reproduction were identified within the AOPN. Twenty-six KEs and 11 KERs were identified as core blocks of knowledge in the AOPN, of which 19 core KEs are already included as parameters in current OECD and US EPA test guidelines. Discussion: The AOPN highlights knowledge gaps that can be targeted for further development of a more complete AOPN that can support the identification and assessment of EDs.
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Affiliation(s)
- Johanna Zilliacus
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Monica K. Draskau
- National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | - Terje Svingen
- National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Anna Beronius
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
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Boberg J, Li T, Christiansen S, Draskau MK, Damdimopoulou P, Svingen T, Johansson HKL. Comparison of female rat reproductive effects of pubertal versus adult exposure to known endocrine disruptors. Front Endocrinol (Lausanne) 2023; 14:1126485. [PMID: 37854179 PMCID: PMC10579898 DOI: 10.3389/fendo.2023.1126485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 09/04/2023] [Indexed: 10/20/2023] Open
Abstract
A prevailing challenge when testing chemicals for their potential to cause female reproductive toxicity is the lack of appropriate toxicological test methods. We hypothesized that starting a 28-day in vivo toxicity study already at weaning, instead of in adulthood, would increase the sensitivity to detect endocrine disruptors due to the possibility of including assessment of pubertal onset. We compared the sensitivity of two rat studies using pubertal or adult exposure. We exposed the rats to two well-known human endocrine disruptors, the estrogen diethylstilbestrol (DES; 0.003, 0.012, 0.048 mg/kg bw/day) and the steroid synthesis inhibitor ketoconazole (KTZ; 3, 12, 48 mg/kg bw/day). Specifically, we addressed the impact on established endocrine-sensitive endpoints including day of vaginal opening (VO), estrous cyclicity, weights of reproductive organs and ovarian histology. After 28 days of exposure, starting either at weaning or at 9 weeks of age, DES exposure altered estrous cyclicity, reduced ovary weight as well as number of antral follicles and corpora lutea. By starting exposure at weaning, we could detect advanced day of VO in DES-exposed animals despite a lower body weight. Some endpoints were affected mainly with adult exposure, as DES increased liver weights in adulthood only. For KTZ, no effects were seen on time of VO, but adrenal and liver weights were increased in both exposure scenarios, and adult KTZ exposure also stimulated ovarian follicle growth. At first glance, this would indicate that a pubertal exposure scenario would be preferrable as timing of VO may serve as sensitive indicator of endocrine disruption by estrogenic mode of action. However, a higher sensitivity for other endocrine targets may be seen starting exposure in adulthood. Overall, starting a 28-day study at weaning with inclusion of VO assessment would mainly be recommended for substances showing estrogenic potential e.g., in vitro, whereas for other substances an adult exposure scenario may be recommended.
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Affiliation(s)
- Julie Boberg
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Tianyi Li
- Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
- Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Sofie Christiansen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Monica K. Draskau
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Pauliina Damdimopoulou
- Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
- Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Terje Svingen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
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Li T, Boberg J, Johansson HKL, Di Nisio V, Christiansen S, Svingen T, Damdimopoulou P. Quantitative analysis of ovarian surface photographs as a tool for assessment of chemical effects on folliculogenesis and ovulation in rats. Reprod Toxicol 2023; 119:108416. [PMID: 37268149 DOI: 10.1016/j.reprotox.2023.108416] [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: 03/18/2023] [Revised: 05/16/2023] [Accepted: 05/27/2023] [Indexed: 06/04/2023]
Abstract
Female reproductive toxicity assessments rely on histological evaluation of ovaries by hematoxylin & eosin (H&E)-stained cross-sections. This is time-consuming, labor-intensive and costly, thus alternative methods for ovarian toxicity assessment could be valuable. Here, we report on an improved method based on quantification of antral follicles (AF) and corpora lutea (CL) using ovarian surface photographs, called 'surface photo counting' (SPC). To validate a potential utility for the method to detect effects on folliculogenesis in toxicity studies, we investigated ovaries from rats exposed to two well-known endocrine disrupting chemicals (EDCs), diethylstilbestrol (DES) and ketoconazole (KTZ). Animals were exposed to DES (0.003, 0.012, 0.048 mg/kg body weight (bw)/day) or KTZ (3, 12, 48 mg/kg bw/day) during puberty or adulthood. At the end of the exposure, ovaries were photographed under stereomicroscope and subsequently processed for histological assessments to allow for direct comparison between the two methods by quantifying AF and CL. There was a significant correlation between the SPC and histology methods, albeit CL counts correlated better than AF counts, potentially due to their larger size. Effects of DES and KTZ were found by both methods, suggesting applicability of the SPC method to chemical hazard and risk assessment. Based on our study, we propose that SPC can be employed as a fast and cheap tool for assessment of ovarian toxicity in in vivo studies to prioritize chemical exposure groups for further histological assessment.
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Affiliation(s)
- Tianyi Li
- Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden; Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Huddinge, SE-14186 Stockholm, Sweden.
| | - Julie Boberg
- National Food Institute, Technical University of Denmark, Kgs, Lyngby DK-2800, Denmark
| | - Hanna K L Johansson
- National Food Institute, Technical University of Denmark, Kgs, Lyngby DK-2800, Denmark
| | - Valentina Di Nisio
- Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden; Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Huddinge, SE-14186 Stockholm, Sweden
| | - Sofie Christiansen
- National Food Institute, Technical University of Denmark, Kgs, Lyngby DK-2800, Denmark
| | - Terje Svingen
- National Food Institute, Technical University of Denmark, Kgs, Lyngby DK-2800, Denmark
| | - Pauliina Damdimopoulou
- Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden; Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Huddinge, SE-14186 Stockholm, Sweden
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Franssen D, Johansson HKL, Lopez-Rodriguez D, Lavergne A, Terwagne Q, Boberg J, Christiansen S, Svingen T, Parent AS. Perinatal exposure to the fungicide ketoconazole alters hypothalamic control of puberty in female rats. Front Endocrinol (Lausanne) 2023; 14:1140886. [PMID: 37077353 PMCID: PMC10108553 DOI: 10.3389/fendo.2023.1140886] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/03/2023] [Indexed: 04/05/2023] Open
Abstract
INTRODUCTION Estrogenic endocrine disrupting chemicals (EDCs) such as diethylstilbestrol (DES) are known to alter the timing of puberty onset and reproductive function in females. Accumulating evidence suggests that steroid synthesis inhibitors such as ketoconazole (KTZ) or phthalates may also affect female reproductive health, however their mode of action is poorly understood. Because hypothalamic activity is very sensitive to sex steroids, we aimed at determining whether and how EDCs with different mode of action can alter the hypothalamic transcriptome and GnRH release in female rats. DESIGN Female rats were exposed to KTZ or DES during perinatal (DES 3-6-12μg/kg.d; KTZ 3-6-12mg/kg.d), pubertal or adult periods (DES 3-12-48μg/kg.d; KTZ 3-12-48mg/kg.d). RESULTS Ex vivo study of GnRH pulsatility revealed that perinatal exposure to the highest doses of KTZ and DES delayed maturation of GnRH secretion before puberty, whereas pubertal or adult exposure had no effect on GnRH pulsatility. Hypothalamic transcriptome, studied by RNAsequencing in the preoptic area and in the mediobasal hypothalamus, was found to be very sensitive to perinatal exposure to all doses of KTZ before puberty with effects persisting until adulthood. Bioinformatic analysis with Ingenuity Pathway Analysis predicted "Creb signaling in Neurons" and "IGF-1 signaling" among the most downregulated pathways by all doses of KTZ and DES before puberty, and "PPARg" as a common upstream regulator driving gene expression changes. Deeper screening ofRNAseq datasets indicated that a high number of genes regulating the activity of the extrinsic GnRH pulse generator were consistently affected by all the doses of DES and KTZ before puberty. Several, including MKRN3, DNMT3 or Cbx7, showed similar alterations in expression at adulthood. CONCLUSION nRH secretion and the hypothalamic transcriptome are highly sensitive to perinatal exposure to both DES and KTZ. The identified pathways should be exploredfurther to identify biomarkers for future testing strategies for EDC identification and when enhancing the current standard information requirements in regulation.
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Affiliation(s)
- Delphine Franssen
- Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Liège, Belgium
- *Correspondence: Delphine Franssen,
| | | | | | - Arnaud Lavergne
- GIGA-Bioinformatics, GIGA Institute, Université de Liège, Liège, Belgium
| | - Quentin Terwagne
- Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Liège, Belgium
| | - Julie Boberg
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Sofie Christiansen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Terje Svingen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Anne-Simone Parent
- Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Liège, Belgium
- Department of Pediatrics, University Hospital Liege, Liege, Belgium
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Kugathas I, Johansson HKL, Chan Sock Peng E, Toupin M, Evrard B, Darde TA, Boberg J, Draskau MK, Rolland AD, Mazaud-Guittot S, Chalmel F, Svingen T. Transcriptional profiling of the developing rat ovary following intrauterine exposure to the endocrine disruptors diethylstilbestrol and ketoconazole. Arch Toxicol 2023; 97:849-863. [PMID: 36653537 PMCID: PMC9968686 DOI: 10.1007/s00204-023-03442-2] [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: 11/11/2022] [Accepted: 01/09/2023] [Indexed: 01/20/2023]
Abstract
Exposure to endocrine-disrupting chemicals (EDCs) during development may cause reproductive disorders in women. Although female reproductive endpoints are assessed in rodent toxicity studies, a concern is that typical endpoints are not sensitive enough to detect chemicals of concern to human health. If so, measured endpoints must be improved or new biomarkers of effects included. Herein, we have characterized the dynamic transcriptional landscape of developing rat ovaries exposed to two well-known EDCs, diethylstilbestrol (DES) and ketoconazole (KTZ), by 3' RNA sequencing. Rats were orally exposed from day 7 of gestation until birth, and from postnatal day 1 until days 6, 14 or 22. Three exposure doses for each chemical were used: 3, 6 and 12 µg/kg bw/day of DES; 3, 6, 12 mg/kg bw/day of KTZ. The transcriptome changed dynamically during perinatal development in control ovaries, with 1137 differentially expressed genes (DEGs) partitioned into 3 broad expression patterns. A cross-species deconvolution strategy based on a mouse ovary developmental cell atlas was used to map any changes to ovarian cellularity across the perinatal period to allow for characterization of actual changes to gene transcript levels. A total of 184 DEGs were observed across dose groups and developmental stages in DES-exposed ovaries, and 111 DEGs in KTZ-exposed ovaries across dose groups and developmental stages. Based on our analyses, we have identified new candidate biomarkers for female reproductive toxicity induced by EDC, including Kcne2, Calb2 and Insl3.
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Affiliation(s)
- Indusha Kugathas
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000 Rennes, France
| | - Hanna K. L. Johansson
- National Food Institute, Technical University of Denmark, Kemitorvet, Building 202, 2800 Kongens Lyngby, Denmark
| | - Edith Chan Sock Peng
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000 Rennes, France
| | - Maryne Toupin
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000 Rennes, France
| | - Bertrand Evrard
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000 Rennes, France
| | | | - Julie Boberg
- National Food Institute, Technical University of Denmark, Kemitorvet, Building 202, 2800 Kongens Lyngby, Denmark
| | - Monica K. Draskau
- National Food Institute, Technical University of Denmark, Kemitorvet, Building 202, 2800 Kongens Lyngby, Denmark
| | - Antoine D. Rolland
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000 Rennes, France
| | - Séverine Mazaud-Guittot
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000 Rennes, France
| | - Frédéric Chalmel
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail) - UMR_S 1085, 9 avenue du Professeur Léon Bernard, 35000, Rennes, France.
| | - Terje Svingen
- National Food Institute, Technical University of Denmark, Kemitorvet, Building 202, 2800, Kongens Lyngby, Denmark.
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Johansson HKL, Christiansen S, Draskau MK, Svingen T, Boberg J. Classical toxicity endpoints in female rats are insensitive to the human endocrine disruptors diethylstilbestrol and ketoconazole. Reprod Toxicol 2021; 101:9-17. [PMID: 33571642 DOI: 10.1016/j.reprotox.2021.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 11/03/2020] [Revised: 12/21/2020] [Accepted: 01/11/2021] [Indexed: 11/21/2022]
Abstract
Developmental exposure to endocrine disrupting chemicals can have negative consequences for reproductive health in both men and women. Our knowledge about how chemicals can cause adverse health outcomes in females is, however, poorer than our knowledge in males. This is possibly due to lack of sensitive endpoints to evaluate endocrine disruption potential in toxicity studies. To address this shortcoming we carried out rat studies with two well-known human endocrine disruptors, diethylstilbestrol (DES) and ketoconazole (KTZ), and evaluated the sensitivity of a series of endocrine related endpoints. Sprague-Dawley rats were exposed orally from gestational day 7 until postnatal day 22. In a range-finding study, disruption of pregnancy-related endpoints was seen from 0.014 mg/kg bw/day for DES and 14 mg/kg bw/day for KTZ, so doses were adjusted to 0.003; 0.006; and 0.0012 mg/kg bw/day DES and 3; 6; or 12 mg/kg bw/day KTZ in the main study. We observed endocrine disrupting effects on sensitive endpoints in male offspring: both DES and KTZ shortened anogenital distance and increased nipple retention. In female offspring, 0.0012 mg/kg bw/day DES caused slightly longer anogenital distance. We did not see effects on puberty onset when comparing average day of vaginal opening; however, we saw a subtle delay after exposure to both chemicals using a time-curve analysis. No effects on estrous cycle were registered. Our study shows a need for more sensitive test methods to protect the reproductive health of girls and women from harmful chemicals.
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Affiliation(s)
- Hanna K L Johansson
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Sofie Christiansen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Monica Kam Draskau
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Terje Svingen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Julie Boberg
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark.
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Boberg J, Johansson HKL, Axelstad M, Olsen GPM, Johansen M, Holmboe SA, Andersson AM, Svingen T. Using assessment criteria for pesticides to evaluate the endocrine disrupting potential of non-pesticide chemicals: Case butylparaben. Environ Int 2020; 144:105996. [PMID: 32771829 DOI: 10.1016/j.envint.2020.105996] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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: 04/23/2020] [Revised: 06/30/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Regulation of chemicals with endocrine disrupting properties depend on the use of the chemical rather than its intrinsic properties. Within the EU, the only criteria currently in place for identifying an endocrine disrupting chemical (EDC) are those developed for biocidal and plant protection products. We argue that ECHA/EFSA guidance for assessing endocrine disrupting properties of biocidal and plant protection products can be applied to all chemicals independent of their intended use. We have assessed the REACH-registered compound butylparaben (CAS 94-36-8), a preservative used primarily in cosmetics. Based on scientific evidence of adverse reproductive effects and endocrine activity, the open literature suggest that butylparaben is an EDC. By applying the ECHA/EFSA guidance for pesticides and biocides, we identify butylparaben as a compound with endocrine disrupting properties. Even though available data is markedly different from that for biocides and pesticides, it was possible to reach this conclusion. More generally, we propose that the ECHA/EFSA guidance can and should be used for identification of EDC regardless of their intended application.
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Affiliation(s)
- Julie Boberg
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark.
| | - Hanna K L Johansson
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Marta Axelstad
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Gustav P M Olsen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Mathias Johansen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Stine A Holmboe
- Department of Growth and Reproduction and International Centre for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Anna-Maria Andersson
- Department of Growth and Reproduction and International Centre for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Terje Svingen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
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Christiansen S, Axelstad M, Scholze M, Johansson HKL, Hass U, Mandrup K, Frandsen HL, Frederiksen H, Isling LK, Boberg J. Grouping of endocrine disrupting chemicals for mixture risk assessment - Evidence from a rat study. Environ Int 2020; 142:105870. [PMID: 32593051 DOI: 10.1016/j.envint.2020.105870] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [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: 02/14/2020] [Revised: 05/26/2020] [Accepted: 05/26/2020] [Indexed: 05/25/2023]
Abstract
Exposure to mixtures of endocrine disrupting chemicals may contribute to the rising incidence of hormone-related diseases in humans. Real-life mixtures are complex, comprised of chemicals with mixed modes of action, and essential knowledge is often lacking on how to group such chemicals into cumulative assessment groups, which is an essential prerequisite to conduct a chemical mixture risk assessment. We investigated if mixtures of chemicals with diverse endocrine modes of action can cause mixture effects on hormone sensitive endpoints in developing and adult rat offspring after perinatal exposure. Wistar rats were exposed during pregnancy and lactation simultaneously to either bisphenol A and butylparaben (Emix), diethylhexyl phthalate and procymidone (Amix), or a mixture of all four substances (Totalmix). In male offspring, the anogenital distance was significantly reduced and nipple retention increased in animals exposed to Amix and Totalmix, and the mixture effects were well approximated by the dose addition model. The combination of Amix and Emix responded with more marked changes on these and other endocrine-sensitive endpoints than each binary mixture on its own. Sperm counts were reduced by all exposures. These experimental outcomes suggest that the grouping of chemicals for mixture risk assessment should be based on common health outcomes rather than only similar modes or mechanisms of action. Mechanistic-based approaches such as the concept of Adverse Outcome Pathway (AOP) can provide important guidance if both the information on shared target tissues and the information on shared mode/mechanism of action are taken into account.
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Affiliation(s)
- Sofie Christiansen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark.
| | - Marta Axelstad
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark
| | - Martin Scholze
- Institute of Environment, Health and Societies, Brunel University London, Quad North, Kingston Lane, Uxbridge UB8 3PH, UK
| | - Hanna K L Johansson
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark
| | - Ulla Hass
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark
| | - Karen Mandrup
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark
| | - Henrik Lauritz Frandsen
- Research Group for Analytical Food Chemistry, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, DK-2800 Kgs. Lyngby, Denmark
| | - Hanne Frederiksen
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Louise Krag Isling
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark
| | - Julie Boberg
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kgs. Lyngby DK-2800, Denmark
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9
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van Duursen MBM, Boberg J, Christiansen S, Connolly L, Damdimopoulou P, Filis P, Fowler PA, Gadella BM, Holte J, Jääger K, Johansson HKL, Li T, Mazaud-Guittot S, Parent AS, Salumets A, Soto AM, Svingen T, Velthut-Meikas A, Bay Wedebye E, Xie Y, van den Berg M. Safeguarding Female Reproductive Health against Endocrine Disrupting Chemicals-The FREIA Project. Int J Mol Sci 2020; 21:E3215. [PMID: 32370092 PMCID: PMC7246859 DOI: 10.3390/ijms21093215] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/21/2020] [Accepted: 04/29/2020] [Indexed: 12/14/2022] Open
Abstract
Currently available test methods are not well-suited for the identification of chemicals that disturb hormonal processes involved in female reproductive development and function. This renders women's reproductive health at increasing risk globally, which, coupled with increasing incidence rates of reproductive disorders, is of great concern. A woman's reproductive health is largely established during embryonic and fetal development and subsequently matures during puberty. The endocrine system influences development, maturation, and function of the female reproductive system, thereby making appropriate hormone levels imperative for correct functioning of reproductive processes. It is concerning that the effects of human-made chemicals on the endocrine system and female reproductive health are poorly addressed in regulatory chemical safety assessment, partly because adequate test methods are lacking. Our EU-funded project FREIA aims to address this need by increasing understanding of how endocrine disrupting chemicals (EDCs) can impact female reproductive health. We will use this information to provide better test methods that enable fit-for-purpose chemical regulation and then share our knowledge, promote a sustainable society, and improve the reproductive health of women globally.
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Affiliation(s)
- Majorie B. M. van Duursen
- Department Environment and Health, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Julie Boberg
- National Food Institute, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark; (J.B.); (S.C.); (H.K.L.J.); (T.S.); (E.B.W.)
| | - Sofie Christiansen
- National Food Institute, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark; (J.B.); (S.C.); (H.K.L.J.); (T.S.); (E.B.W.)
| | - Lisa Connolly
- The Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, Belfast BT9 5DL, Northern Ireland, UK; (L.C.); (Y.X.)
| | - Pauliina Damdimopoulou
- Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet and Karolinska University Hospital, SE-14186 Stockholm, Sweden; (P.D.); (T.L.)
| | - Panagiotis Filis
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, Foresterhill, Aberdeen AB23 8ZD, UK; (P.F.); (P.A.F.)
| | - Paul A. Fowler
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, Foresterhill, Aberdeen AB23 8ZD, UK; (P.F.); (P.A.F.)
| | - Bart M. Gadella
- Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands; (B.M.G.); (M.v.d.B.)
| | - Jan Holte
- Carl von Linné Clinic, Uppsala Science Park, S-751 83 Uppsala, Sweden;
| | - Kersti Jääger
- Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu and Competence Centre on Health Technologies, Teaduspargi 13, 50411 Tartu, Estonia; (K.J.); (A.S.)
| | - Hanna K. L. Johansson
- National Food Institute, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark; (J.B.); (S.C.); (H.K.L.J.); (T.S.); (E.B.W.)
| | - Tianyi Li
- Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet and Karolinska University Hospital, SE-14186 Stockholm, Sweden; (P.D.); (T.L.)
| | - Séverine Mazaud-Guittot
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)—UMR_S 1085, F-35000 Rennes, France;
| | - Anne-Simone Parent
- Neuroendocrinology Unit, GIGA-Institute, University of Liège, Belgium.1, Avenue de l’hôpital, 4000 Liège, Belgium;
| | - Andres Salumets
- Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu and Competence Centre on Health Technologies, Teaduspargi 13, 50411 Tartu, Estonia; (K.J.); (A.S.)
| | - Ana M. Soto
- Department of Immunology, Tufts University School of Medicine, Boston, MA 0211, USA;
| | - Terje Svingen
- National Food Institute, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark; (J.B.); (S.C.); (H.K.L.J.); (T.S.); (E.B.W.)
| | - Agne Velthut-Meikas
- Department of Chemistry and Biotechnology, School of Science, Tallinn University of Technology, 12618 Tallinn, Estonia;
| | - Eva Bay Wedebye
- National Food Institute, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark; (J.B.); (S.C.); (H.K.L.J.); (T.S.); (E.B.W.)
| | - Yuling Xie
- The Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, Belfast BT9 5DL, Northern Ireland, UK; (L.C.); (Y.X.)
| | - Martin van den Berg
- Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands; (B.M.G.); (M.v.d.B.)
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10
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Boberg J, Johansson HKL, Hadrup N, Dreisig K, Berthelsen L, Almstrup K, Vinggaard AM, Hass U. Perinatal exposure to mixtures of anti-androgenic chemicals causes proliferative lesions in rat prostate. Prostate 2015; 75:126-40. [PMID: 25327291 DOI: 10.1002/pros.22897] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 08/21/2014] [Indexed: 11/07/2022]
Abstract
BACKGROUND Elevated levels of endogenous or exogenous estrogens during fetal life can induce permanent disturbances in prostate growth and predispose to precancerous lesions. Recent studies have indicated that also early anti-androgen exposure may affect prostate cancer risk. METHODS We examined the influence of perinatal exposure to mixtures of anti-androgenic and estrogenic chemicals on prostate development. Wistar rats were exposed from gestation day 7 to postnatal day 22 to a mixture of 8 anti-androgenic compounds (AAMix), a mixture of four estrogenic compounds (EMix), or paracetamol or a mixture of all 13 compounds (TotalMix) in mixture ratios reflecting human exposure levels. RESULTS Ventral prostate weights were reduced by the TotalMix and AAMix in pre-pubertal rats. Histological changes in prostate appeared with increasing age and indicated a shift from the normal age-dependent epithelial atrophy towards hyperplasia. These lesions showed similarities to pre-cancerous lesions in humans. Increased proliferation was observed already in pre-puberty and it was hypothesized that this could be associated with reduced ERβ signaling, but no clear conclusions could be made from gene expression studies on ERβ-related pathways. The influences of the estrogenic chemicals and paracetamol on prostate morphology were minor, but in young adulthood the estrogen mixture reduced ventral prostate mRNA levels of Igf1 and paracetamol reduced the mRNA level ofPbpc3. CONCLUSIONS Mixtures of endocrine disrupters relevant for human exposure was found to elicit persistent effects on the rat prostate following perinatal exposure, suggesting that human perinatal exposure to environmental chemicals may increase the risk of prostate cancer later in life.
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Affiliation(s)
- Julie Boberg
- Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, Søborg, Denmark
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11
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Cedergreen N, Nørhave NJ, Nielsen K, Johansson HKL, Marcussen H, Svendsen C, Spurgeon DJ. Low temperatures enhance the toxicity of copper and cadmium to Enchytraeus crypticus through different mechanisms. Environ Toxicol Chem 2013; 32:2274-83. [PMID: 23661382 DOI: 10.1002/etc.2274] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 07/27/2012] [Revised: 10/15/2012] [Accepted: 04/22/2013] [Indexed: 05/07/2023]
Abstract
Knowledge about how toxicity changes with temperature is important for determining the extent of safety factors required when extrapolating from standard laboratory conditions to variable field scenarios. In the present study, the authors evaluated the toxicity of Cu and Cd to the potworm Enchytraeus crypticus at 6 temperatures in the range of 11 °C to 25 °C. For both metals, reproductive toxicity decreased approximately 2.5-fold with increasing temperature. This is contrary to what most other studies have found. Measurements of the bioavailable fraction of the metals in the soils and the internal metal concentrations in the worms over time showed that the major cause of change in toxicity with temperature for Cu was the worms' ability to regulate internal concentration at high temperatures. Uptake of Cd increased with time at all temperatures and with higher rates at high temperatures. Hence, the lower toxicity of Cd at high temperatures is proposed to be due to the E. crypticus being more efficient at immobilizing Cd and/or repairing damages at high compared to low temperatures. The present study concludes that no consistent relationship between metal toxicity and temperature across species can be made. The metabolic dependence of the species in terms of regulating metal uptake, excretion, immobilization, damage, and repair processes, will be crucial factors in determining species susceptibility to metals at varying temperatures.
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Affiliation(s)
- Nina Cedergreen
- Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark.
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