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Holmer ML, Zilliacus J, Draskau MK, Hlisníková H, Beronius A, Svingen T. Methodology for developing data-rich Key Event Relationships for Adverse Outcome Pathways exemplified by linking decreased androgen receptor activity with decreased anogenital distance. Reprod Toxicol 2024; 128:108662. [PMID: 38986849 DOI: 10.1016/j.reprotox.2024.108662] [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: 06/12/2024] [Revised: 07/03/2024] [Accepted: 07/06/2024] [Indexed: 07/12/2024]
Abstract
The Adverse Outcome Pathway (AOP) framework has gained widespread acceptance in toxicological disciplines as a tool for aiding chemical hazard assessment. Despite increased activity in AOP development, progress towards a high volume of fully endorsed AOPs has been slow, partly due to the challenging task of constructing complete AOPs according to the AOP Developer's Handbook. To facilitate greater uptake of new knowledge units onto the open-source AOP-wiki platform, a pragmatic approach was recently proposed. This approach involves considering Key Event Relationships (KERs) for individual development through systematic approaches, as they represent essential units of knowledge from which causality can be inferred; from low complexity test data to adverse outcomes in intact organisms. However, more broadly adopted harmonized methodologies for KER development would be desirable. Using the AOP Developer's Handbook as a guide, a KER linking 'decreased androgen receptor (AR) activity' with 'reduced anogenital distance (AGD)' was developed to demonstrate a methodology applicable for future developments of KERs requiring systematic literature retrieval approaches.
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Affiliation(s)
- Marie L Holmer
- National Food Institute, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark.
| | - Johanna Zilliacus
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Monica K Draskau
- National Food Institute, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark
| | - Henrieta Hlisníková
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Anna Beronius
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Terje Svingen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark
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Ye R, Li Z, Xian H, Zhong Y, Liang B, Huang Y, Chen D, Dai M, Tang S, Guo J, Bai R, Feng Y, Chen Z, Yang X, Huang Z. Combined Effects of Polystyrene Nanosphere and Homosolate Exposures on Estrogenic End Points in MCF-7 Cells and Zebrafish. ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:27011. [PMID: 38381479 PMCID: PMC10880820 DOI: 10.1289/ehp13696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 01/05/2024] [Accepted: 01/08/2024] [Indexed: 02/22/2024]
Abstract
BACKGROUND Micro- and nanoplastics (MNPs) and homosalate (HMS) are ubiquitous emerging environmental contaminants detected in human samples. Despite the well-established endocrine-disrupting effects (EDEs) of HMS, the interaction between MNPs and HMS and its impact on HMS-induced EDEs remain unclear. OBJECTIVES This study aimed to investigate the influence of MNPs on HMS-induced estrogenic effects and elucidate the underlying mechanisms in vitro and in vivo. METHODS We assessed the impact of polystyrene nanospheres (PNSs; 50 nm , 1.0 mg / L ) on HMS-induced MCF-7 cell proliferation (HMS: 0.01 - 1 μ M , equivalent to 2.62 - 262 μ g / L ) using the E-SCREEN assay and explored potential mechanisms through transcriptomics. Adult zebrafish were exposed to HMS (0.0262 - 262 μ g / L ) with or without PNSs (50 nm , 1.0 mg / L ) for 21 d. EDEs were evaluated through gonadal histopathology, fertility tests, steroid hormone synthesis, and gene expression changes in the hypothalamus-pituitary-gonad-liver (HPGL) axis. RESULTS Coexposure of HMS and PNSs resulted in higher expression of estrogen receptor α (ESR1) and the mRNAs of target genes (pS2, AREG, and PGR), a greater estrogen-responsive element transactivation activity, and synergistic stimulation on MCF-7 cell proliferation. Knockdown of serum and glucocorticoid-regulated kinase 1 (SGK1) rescued the MCF-7 cell proliferation induced by PNSs alone or in combination with HMS. In zebrafish, coexposure showed higher expression of SGK1 and promoted ovary development but inhibited spermatogenesis. In addition, coexposure led to lower egg hatchability, higher embryonic mortality, and greater larval malformation. Coexposure also modulated steroid hormone synthesis genes (cyp17a2, hsd17[Formula: see text]1, esr2b, vtg1, and vtg2), and resulted in higher 17 β -estradiol (E 2 ) release in females. Conversely, males showed lower testosterone, E 2 , and gene expressions of cyp11a1, cyp11a2, cyp17a1, cyp17a2, and hsd17[Formula: see text]1. DISCUSSION PNS exposure exacerbated HMS-induced estrogenic effects via SGK1 up-regulation in MCF-7 cells and disrupting the HPGL axis in zebrafish, with gender-specific patterns. This offers new mechanistic insights and health implications of MNP and contaminant coexposure. https://doi.org/10.1289/EHP13696.
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Affiliation(s)
- Rongyi Ye
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Zhiming Li
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Hongyi Xian
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yizhou Zhong
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Boxuan Liang
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yuji Huang
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Da Chen
- College of Environment and Climate, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, China
| | | | - Shuqin Tang
- College of Environment and Climate, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, China
| | - Jie Guo
- Hunter Biotechnology, Inc, Hangzhou, China
| | - Ruobing Bai
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yu Feng
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Zhenguo Chen
- Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xingfen Yang
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Food Safety and Health Research Center, School of Public Health, Southern Medical University, Guangzhou, China
| | - Zhenlie Huang
- National Medical Products Administration (NMPA) Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
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Varde M, Newman RB, Wenzel AG, Kucklick JR, Wineland RJ, Brock JW, Bloom MS. Racial disparities affect the association between gestational urinary phthalate mixtures and infant genital measures. FRONTIERS IN REPRODUCTIVE HEALTH 2023; 5:1304725. [PMID: 38146361 PMCID: PMC10749323 DOI: 10.3389/frph.2023.1304725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 11/22/2023] [Indexed: 12/27/2023] Open
Abstract
Background Phthalates are ubiquitous anti-androgenic endocrine disrupting chemicals found in personal care products, medications, and many plastics. Studies have shown a racial disparity in phthalates exposure among U.S. women, which may also impact fetal development. Methods We conducted a prospective cohort study of gestational exposure to a phthalates mixture in a racially-diverse population to determine their association with genital development. Mid-gestation (18-22 weeks) urine was collected from 152 women who self-identified as non-Hispanic Black and 158 women who self-identified as non-Hispanic White in Charleston, South Carolina between 2011 and 2014. We measured eight phthalate monoester metabolites in urine using liquid chromatography tandem-mass spectrometry. Mid-gestational penile dimensions were measured using ultrasound and anogenital distances were measured postnatally. We used Bayesian kernel machine regression to estimate the associations among the mixture of phthalate metabolites and mid-gestation penile dimensions and postnatal anogenital distance measures among singleton male (n = 179) and female (n = 131) infants, adjusted for urinary specific gravity, maternal age, body mass index, education level, cigarette smoking, and gestational age at enrollment or birth weight z-score. Results We found a stronger association between greater phthalates and decreased anopenile distance among infants born to women who self-identified as Black. Mono (2-ethylhexyl) phthalate (MEHP) was the driving mixture component among Black women, and monobutyl phthalate (MBP) and monoethyl phthalate (MEP) were drivers among White women. We also identified a non-linear association between phthalates and lesser ultrasound penile volume among women who self-identified as Black with monoisobutyl phthalate (MiBP) and MBP being most important. We also found an association between greater phthalates and shorter anoclitoral distance among infants born to women who self-identified as Black, with MEP and monobenzyl phthalate (MBzP) contributing most to this association. Conclusion Our results suggest a disparity in the association between gestational exposure to a mixture of phthalates and fetal genital development among women who self-identified as Black compared to White.
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Affiliation(s)
- Meghana Varde
- Department of Global and Community Health, George Mason University, Fairfax, VA, United States
| | - Roger B. Newman
- Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, SC, United States
| | - Abby G. Wenzel
- Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, SC, United States
| | - John R. Kucklick
- Hollings Marine Laboratory, National Institute of Standards and Technology, Charleston, SC, United States
| | - Rebecca J. Wineland
- Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, SC, United States
| | - John W. Brock
- Department of Chemistry, University of North Carolina Asheville, Asheville, NC, United States
| | - Michael S. Bloom
- Department of Global and Community Health, George Mason University, Fairfax, VA, United States
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Chen H, Liu M, Li Q, Zhou P, Huang J, Zhu Q, Li Z, Ge RS. Exposure to dipentyl phthalate in utero disrupts the adrenal cortex function of adult male rats by inhibiting SIRT1/PGC-1α and inducing AMPK phosphorylation. ENVIRONMENTAL TOXICOLOGY 2023; 38:997-1010. [PMID: 36715143 DOI: 10.1002/tox.23743] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 12/23/2022] [Accepted: 01/16/2023] [Indexed: 06/18/2023]
Abstract
Di-n-pentyl phthalate (DPeP) is an endocrine-disrupting phthalate plasticizer. The objective of this study was to investigate the effect of DPeP on adrenocortical function in adult male rats following in utero exposure. DPeP (0, 10, 50, 100, and 500 mg/kg/day) was administered by gavage to pregnant Sprague-Dawley rats from gestational day 14 to 21. The morphology and function of the adrenal cortex in 56-day-old male offspring were studied. DPeP at 100 and 500 mg/kg/day significantly reduced serum aldosterone levels and at 500 mg/kg/day markedly reduced corticosterone and adrenocorticotropic hormone levels. DPeP at 10-500 mg/kg markedly reduced the thickness of zona glomerulosa without affecting the thickness of zona fasciculata. DPeP significantly downregulated the expression of Agtr1a, Mc2r, Scarb1, Cyp11a1, Hsd3b1, Cyp21, Cyp11b1, Cyp11b2, Nr5a1, Nr4a2, and Bcl2 genes as well as their proteins. DPeP at 500 mg/kg/day significantly increased phosphorylated AMPK, while DPeP at 100 mg/kg/day and higher doses reduced phosphorylated AKT1 and total SIRT1 level. DPeP at 100 and 500 μM markedly induced reactive oxygen species and apoptosis in H295R cells after 24 h of culture. In conclusion, in utero exposure to DPeP disrupts adrenocortical function of the adult male offspring by (1) increasing AMPK phosphorylation and decreasing AKT1 phosphorylation and SIRT1 levels, (2) reducing adrenocorticotropic hormone levels, and (3) possibly inducing oxidative stress and apoptosis.
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Affiliation(s)
- Haiqiong Chen
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
- Department of Traumatology, The Children's Hospital Zhejiang University School of Medicine, Hangzhou, China
| | - Miaoqing Liu
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Qiyao Li
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Pingjiang Zhou
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jie Huang
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Qiqi Zhu
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Zhongrong Li
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Ren-Shan Ge
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
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Earl Gray L. Biologically relevant reductions in fetal testosterone and Insl3 induced by in utero exposure to high levels of di-isononyl phthalate (DINP) in male rats. Toxicol Appl Pharmacol 2023; 465:116454. [PMID: 36921846 PMCID: PMC10405973 DOI: 10.1016/j.taap.2023.116454] [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: 10/30/2022] [Revised: 03/02/2023] [Accepted: 03/04/2023] [Indexed: 03/16/2023]
Abstract
Some phthalate esters alter male rat reproductive development during sexual differentiation by interfering with fetal testis maturation resulting in reduced Leydig Cell synthesis of testosterone and insulin-like 3 (Insl3) hormones. Gene transcripts associated with steroid hormone and cholesterol transport, and cholesterol synthesis and lipid metabolism also are reduced. These alterations cause permanent malformations of hormone-dependent tissues, sperm production and fertility in male offspring; effects known as the "Phthalate Syndrome." We have shown that administration of a high dose of 750 mg diisononyl phthalate (750 mg/kg/d DINP) during sex differentiation reduced fetal testis testosterone production (T Prod), testis gene expression and induced a low incidence of reproductive malformations in male rat offspring. In the current study we administered DINP at even higher dose levels (1.0 and 1.5 g/kg/d) from gestational day (GD) 14 to postnatal (PND) 3 to determine if these effects were dose related and if the magnitude of the effects could be predicted from a statistical model of fetal testosterone production (T Prod) and Insl3 mRNA levels. These models were previously developed using dipentyl phthalate (DPeP) data from fetal T Prod and postnatal studies. We found that the severity of the demasculinizing effects on the androgen-dependent organs and gubernaculum by DINP were accurately predicted from the statistical models of fetal T prod and Insl3 mRNA, respectively. Taken together, our results indicate that reductions fetal T prod and Insl3 predict the severity of demasculinizing effects in utero exposure to the phthalates DINP and DPeP regardless of potency.
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Affiliation(s)
- L Earl Gray
- Reproductive And Developmental Toxicology Branch, PHITD, CPHEA, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, Mail Drop-72, NC 27711, United States of America.
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6
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Xia LZ, Jiang MZ, Liu LL, Wu Y, Zhang YL, Yang LX, Shen XY, Zhang QY, Lin M, Gao HT. Quercetin inhibits testicular toxicity induced by the mixture of three commonly used phthalates in rats. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023; 103:1541-1549. [PMID: 36197122 DOI: 10.1002/jsfa.12251] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 07/21/2022] [Accepted: 10/05/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Phthalates (PEs), such as butyl benzyl phthalate, dibutyl phthalate and di(2-ethylhexyl) phthalate, are one of the most widely used plasticizers, and humans are increasingly exposed to them. Phytochemical quercetin (Que) is a typical flavonoid with several biological effects, such as antioxidative and anti-inflammatory. The present study was designed to explore the effect of Que on testicular toxicity caused by the mixture of three commonly used PEs (MPEs), and the underlying mechanism. Forty male Sprague-Dawley rats were randomly and equally divided into five groups (n = 8). Rats in control the group were orally treated with the excipient. Rats in the MPEs group were orally administered with 900 mg kg-1 day-1 MPEs, whereas rats in the MPEs+L-Que, MPEs+M-Que and MPEs+H-Que groups were simultaneously treated with 900 mg kg-1 day-1 MPEs and, respectively, 10, 30 and 90 mg kg-1 day-1 Que for 30 days. RESULTS Compared with the control group, the testes weight, epididymides weight, serum testosterone, luteinizing hormone, follicle-stimulating hormone and estradiol levels, and anogenital distance in the MPEs group were significantly decreased (P < 0.05). The testicular tissues were injured with atrophy of seminiferous tubules, hyperplasia of Leydig cells and arrest of spermatogenesis in the MPEs group. Testicular steroidogenic proteins (StAR, P450scc, CYP17A1 and 17β-HSD, P450arom) were up-regulated, whereas P-element-induced wimpy testis proteins (PIWIL1 and PIWIL2) were down-regulated in the MPEs group (P < 0.05). However, the alterations of these parameters were inhibited in the MPEs+M-Que and MPEs+H-Que groups. CONCLUSION MPEs disturbed steroid hormone metabolism and caused testicular injuries. Que could inhibit testicular toxicity of MPEs, which might relate to the improved regulation of steroid hormone metabolism. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Ling-Zi Xia
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
- Zhejiang Provincial Key Laboratory of Watershed Science and Health, Wenzhou Medical University, Wenzhou, China
| | - Ming-Zhe Jiang
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Li-Lan Liu
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
- Zhejiang Provincial Key Laboratory of Watershed Science and Health, Wenzhou Medical University, Wenzhou, China
| | - Yi Wu
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Yi-Lin Zhang
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Li-Xia Yang
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Xin-Yue Shen
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Qiu-Yu Zhang
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Min Lin
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Hai-Tao Gao
- Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
- Zhejiang Provincial Key Laboratory of Watershed Science and Health, Wenzhou Medical University, Wenzhou, China
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Alhasnani MA, Loeb S, Hall SJ, Caruolo Z, Simmonds F, Solano AE, Spade DJ. Interaction between mono-(2-ethylhexyl) phthalate and retinoic acid alters Sertoli cell development during fetal mouse testis cord morphogenesis. Curr Res Toxicol 2022; 3:100087. [PMID: 36189433 PMCID: PMC9520016 DOI: 10.1016/j.crtox.2022.100087] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 09/17/2022] [Accepted: 09/17/2022] [Indexed: 11/24/2022] Open
Abstract
Phthalic acid esters (phthalates) are a class of industrial chemicals that cause developmental and reproductive toxicity, but there are significant gaps in knowledge of phthalate toxicity mechanisms. There is evidence that phthalates disrupt retinoic acid signaling in the fetal testis, potentially disrupting control of spatial and temporal patterns of testis development. Our goal was to determine how a phthalate would interact with retinoic acid signaling during fetal mouse testis development. We hypothesized that mono-(2-ethylhexyl) phthalate (MEHP) would exacerbate the adverse effect of all-trans retinoic acid (ATRA) on seminiferous cord development in the mouse fetal testis. To test this hypothesis, gestational day (GD) 14 C57BL/6 mouse testes were isolated and cultured on media containing MEHP, ATRA, or a combination of both compounds. Cultured testes were collected for global transcriptome analysis after one day in culture and for histology and immunofluorescent analysis of Sertoli cell differentiation after three days in culture. ATRA disrupted seminiferous cord morphogenesis and induced aberrant FOXL2 expression. MEHP alone had no significant effect on cord development, but combined exposure to MEHP and ATRA increased the number of FOXL2-positive cells, reduced seminiferous cord number, and increased testosterone levels, beyond the effect of ATRA alone. In RNA-seq analysis, ATRA treatment and MEHP treatment resulted in differential expression of genes 510 and 134 genes, respectively, including 70 common differentially expressed genes (DEGs) between the two treatments, including genes with known roles in fetal testis development. MEHP DEGs included RAR target genes, genes involved in angiogenesis, and developmental patterning genes, including members of the homeobox superfamily. These results support the hypothesis that MEHP modulates retinoic acid signaling in the mouse fetal testis and provide insight into potential mechanisms by which phthalates disrupt seminiferous cord morphogenesis.
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Key Words
- ATRA, All-trans retinoic acid. CAS # 302-79-4
- DMSO, dimethyl sulfoxide
- Fetal testis development
- GD, gestational day
- GO, Gene Ontology
- IPA, Ingenuity Pathway Analysis
- ITCN, Image-based Tool for Counting Nuclei
- MEHP, mono-(2-ethylheyxl) phthalate. CAS # 4376-20-9
- MNGs, multinucleated germ cells
- PVC, polyvinyl chloride
- Phthalate toxicity
- Retinoic acid
- Sertoli cell
- TDS, testicular dysgenesis syndrome
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Affiliation(s)
- Maha A. Alhasnani
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
| | - Skylar Loeb
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
| | - Susan J. Hall
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
| | - Zachary Caruolo
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
| | - Faith Simmonds
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
| | - Amanda E. Solano
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
| | - Daniel J. Spade
- Department of Pathology and Laboratory Medicine, Brown University, Box G-E5, Providence, RI 02912, USA
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Barbagallo S, Baldauf C, Orosco E, Roy NM. Di-butyl phthalate (DBP) induces defects during embryonic eye development in zebrafish. ECOTOXICOLOGY (LONDON, ENGLAND) 2022; 31:178-185. [PMID: 34773557 DOI: 10.1007/s10646-021-02468-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
Di-butyl phthalate (DBP) is a phthalate ester (PAEs) added during the manufacturing of plastics to make them stronger, yet more pliable. DBP is noncovalently bound to plastics resulting in leaching into the environment. Concerning concentrations of DBP have been noted in surface and groundwater, aquatic ecosystems, soil and atmospheric environments globally. Global production of phthalates and thus concomitant exposure has increased over the years making studies on the ecological and environmental safety needed. Most of the literature on DBP focuses on the endocrine disrupting properties of phthalate esters, but the developmental toxicity of DBP is an understudied area. Here, we treat gastrula staged zebrafish embryos with environmentally relevant concentrations of DBP (2.5 µM). We find defects in eye development at 96 h post fertilization including a decrease in the size of the lens and retina in DBP-treated embryos. Defects in eye vascularization as well as loss of the optic nerve and optic tectum were also noted. Here we conclude that exposure to environmentally relevant doses of DBP during early embryonic development is toxic to eye development.
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Affiliation(s)
| | - Cassidy Baldauf
- Department of Biology, Sacred Heart University, Fairfield, CT, USA
| | - Emily Orosco
- Department of Biology, Sacred Heart University, Fairfield, CT, USA
| | - Nicole M Roy
- Department of Biology, Sacred Heart University, Fairfield, CT, USA.
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Conley JM, Lambright CS, Evans N, Cardon M, Medlock-Kakaley E, Wilson VS, Gray LE. A mixture of 15 phthalates and pesticides below individual chemical no observed adverse effect levels (NOAELs) produces reproductive tract malformations in the male rat. ENVIRONMENT INTERNATIONAL 2021; 156:106615. [PMID: 34000504 PMCID: PMC8380680 DOI: 10.1016/j.envint.2021.106615] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 05/10/2023]
Abstract
Humans carry residues of multiple synthetic chemicals at any given point in time. Research has demonstrated that compounds with varying molecular initiating events (MIE) that disrupt common key events can act in concert to produce cumulative adverse effects. Congenital defects of the male reproductive tract are some of the most frequently diagnosed malformations in humans and chemical exposures in utero can produce these effects in laboratory animals and humans. Here, we hypothesized that in utero exposure to a mixture of pesticides and phthalates, each of which produce male reproductive tract defects individually, would produce cumulative effects even when each chemical is present at a no observed adverse effect level (NOAEL) specific for male reproductive effects. Pregnant Sprague-Dawley rats were exposed via oral gavage to a fixed-ratio dilution mixture of 5 pesticides (vinclozolin, linuron, procymidone, prochloraz, pyrifluquinazon), 1 pesticide metabolite (dichlorodiphenyldichloroethylene (DDE)), and 9 phthalates (dipentyl, dicyclohexyl, di-2-ethylhexyl, dibutyl, benzyl butyl, diisobutyl, diisoheptyl, dihexyl, and diheptyl) during the critical window of rat fetal masculinization (gestation day 14-18). The top dose (100% dose) contained each compound at a concentration 2-fold greater than the individual chemical NOAEL followed by a dilution series that represented each chemical at NOAEL, NOAEL/2, NOAEL/4, NOAEL/8, NOAEL/15, NOAEL/100, NOAEL/1000. Reduced fetal testis gene expression occurred at NOAEL/15, reduced fetal testis testosterone production occurred at NOAEL/8, reduced anogenital distance, increased nipple retention, and delayed puberty occurred at NOAEL/4, and severe effects including genital malformations and weight reductions in numerous reproductive tissues occurred at NOAEL/2. This study demonstrates that these phthalates and pesticides acted cumulatively to produce adverse effects at doses below which any individual chemical had been shown to produce an effect alone and even though they have different MIEs.
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Affiliation(s)
- Justin M Conley
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
| | - Christy S Lambright
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
| | - Nicola Evans
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
| | - Mary Cardon
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
| | - Elizabeth Medlock-Kakaley
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
| | - Vickie S Wilson
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
| | - L Earl Gray
- U.S. Environmental Protection Agency/Office of Research & Development/Center for Public Health and Environmental Assessment/Public Health and Integrated Toxicology Division, Research Triangle Park, NC 27711, United States.
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10
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Liu M, Chen H, Dai H, Zhou L, Wang Y, Xin X, Chen C, Li Z, Ge RS. Effects of bis(2-butoxyethyl) phthalate exposure in utero on the development of fetal Leydig cells in rats. Toxicol Lett 2021; 351:65-77. [PMID: 34454012 DOI: 10.1016/j.toxlet.2021.08.008] [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] [Received: 05/13/2021] [Revised: 08/18/2021] [Accepted: 08/20/2021] [Indexed: 10/20/2022]
Abstract
Phthalates are plasticizers widely found in the environment. They are potential endocrine disruptors. Bis(2-butoxyethyl) phthalate (BBOP) is a unique phthalate that contains oxygen atoms in the carbon backbone. Little is known about its reproductive and developmental toxicity. The objective of this study was to determine the effect of BBOP on fetal Leydig cell development after in utero exposure to rats. Sprague Dawley pregnant dams were randomly allocated into 6 groups, and were gavaged with BBOP (0, 10, 100, 250, 500, and 1000 mg/kg body weight/day) from gestational day (GD) 14-21. Seven of the 8 dams in the 1000 mg/kg BBOP group died before giving birth. Twelve of the 20 dams in the 500 mg/kg BBOP group had whole litter loss. BBOP significantly reduced the body weight of dams and male offspring and serum testosterone level and anogenital distance of male fetus on GD 21 at 500 mg/kg. BBOP markedly increased fetal Leydig cell proliferation and number at 500 mg/kg while inducing their abnormal aggregation at 250 and 500 mg/kg. BBOP down-regulated the expression of Lhcgr, Scarb1, Star, Cyp11a1, Hsd3b1, Cyp17a1, Hsd17b3, Insl3, and Nr5a1 at various doses while up-regulating the expression of Sertoli cell gene Fshr and Sox9. The phosphorylation of AKT1, AKT2, and ERK1/2 was also markedly reduced by BBOP. In conclusion, BBOP in utero exposure can disrupt fetal Leydig cell development, possibly via the mechanism that may include inhibiting the phosphorylation of AKT1, AKT2, and ERK1/2.
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Affiliation(s)
- Miaoqing Liu
- Department of Pediatric Surgery, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Haiqiong Chen
- Department of Pediatric Surgery, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Haipeng Dai
- Department of Pediatric Surgery, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Liangbi Zhou
- Department of Pediatric Surgery, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yiyan Wang
- Department of Anesthesiology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiu Xin
- Department of Anesthesiology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Congde Chen
- Department of Pediatric Surgery, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhongrong Li
- Department of Pediatric Surgery, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Ren-Shan Ge
- Department of Anesthesiology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
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11
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Gray LE, Lambright CS, Conley JM, Evans N, Furr JR, Hannas BR, Wilson VS, Sampson H, Foster PMD. Genomic and Hormonal Biomarkers of Phthalate-Induced Male Rat Reproductive Developmental Toxicity Part II: A Targeted RT-qPCR Array Approach That Defines a Unique Adverse Outcome Pathway. Toxicol Sci 2021; 182:195-214. [PMID: 33983380 DOI: 10.1093/toxsci/kfab053] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Previously, we demonstrated that exposure to some diortho-phthalate esters during sexual differentiation disrupts male reproductive development by reducing fetal rat testis testosterone production (T Prod) and gene expression in a dose-related manner. The objectives of the current project were to expand the number of test compounds that might reduce fetal T Prod, including phthalates, phthalate alternatives, pesticides, and drugs, and to compare reductions in T Prod with altered testis mRNA expression. We found that PEs that disrupt T Prod also reduced expression of a unique "cluster" of mRNAs for about 35 genes related to sterol transport, testosterone and insulin-like hormone 3 hormone syntheses, and lipoprotein signaling and cholesterol synthesis. However, phthalates had little or no effect on mRNA expression of genes in peroxisome proliferator-activated receptor (PPAR) pathways in the fetal liver, whereas the 3 PPAR agonists induced the expression of mRNA for multiple fetal liver PPAR pathway genes without reducing testis T Prod. In summary, phthalates that disrupt T Prod act via a novel adverse outcome pathway including down regulation of mRNA for genes involved in fetal endocrine function and cholesterol synthesis and metabolism. This profile was not displayed by PEs that did not reduce T Prod, PPAR agonists or the other chemicals. Reductions in fetal testis gene expression and T Prod in utero can be used to establish relative potency factors that can be used quantitatively to predict the doses of individual PEs and mixtures of phthalates that produce adverse reproductive tract effects in male offspring.
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Affiliation(s)
- Leon Earl Gray
- Reproductive and Developmental Toxicology Branch, PHITD, CPHEA, ORD, US Environmental Protection Agency, North Carolina 27711, USA
| | - Christy S Lambright
- Reproductive and Developmental Toxicology Branch, PHITD, CPHEA, ORD, US Environmental Protection Agency, North Carolina 27711, USA
| | - Justin M Conley
- Reproductive and Developmental Toxicology Branch, PHITD, CPHEA, ORD, US Environmental Protection Agency, North Carolina 27711, USA
| | - Nicola Evans
- Reproductive and Developmental Toxicology Branch, PHITD, CPHEA, ORD, US Environmental Protection Agency, North Carolina 27711, USA
| | | | - Bethany R Hannas
- Corteva, Agriscience, Haskell R&D Center, Newark, Delaware 19711, USA
| | - Vickie S Wilson
- Reproductive and Developmental Toxicology Branch, PHITD, CPHEA, ORD, US Environmental Protection Agency, North Carolina 27711, USA
| | - Hunter Sampson
- Reproductive and Developmental Toxicology Branch, PHITD, CPHEA, ORD, US Environmental Protection Agency, North Carolina 27711, USA
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12
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Gray LE, Furr JR, Lambright CS, Evans N, Hartig PC, Cardon MC, Wilson VS, Hotchkiss AK, Conley JM. Quantification of the Uncertainties in Extrapolating From In Vitro Androgen Receptor Antagonism to In Vivo Hershberger Assay Endpoints and Adverse Reproductive Development in Male Rats. Toxicol Sci 2021; 176:297-311. [PMID: 32421828 DOI: 10.1093/toxsci/kfaa067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Multiple molecular initiating events exist that disrupt male sexual differentiation in utero including androgen receptor (AR) antagonism and inhibition of synthesis, and metabolism of fetal testosterone. Disruption of androgen signaling by AR antagonists in utero reduces anogenital distance (AGD) and induces malformations in F1 male rat offspring. We are developing a quantitative network of adverse outcome pathways that includes multiple molecular initiating events and key events linking anti-AR activities to permanent reproductive abnormalities. Here, our objective was to determine how accurately the EC50s for AR antagonism in vitro or ED50s for reduced tissue growth in the Hershberger assay (HA) (key events in the adverse outcome pathway) predict the ED50s for reduced AGD in male rats exposed in utero to AR antagonists. This effort included in-house data and published studies from the last 60 years on AR antagonism in vitro and in vivo effects in the HA and on AGD after in utero exposure. In total, more than 250 studies were selected and included in the analysis with data from about 60 potentially antiandrogenic chemicals. The ability to predict ED50s for key events and adverse developmental effects from the in vitro EC50s displays considerable uncertainty with R2 values for HA and AGD of < 6%. In contrast, there is considerably less uncertainty in extrapolating from the ED50s in the HA to the ED50s for AGD (R2 value of about 85%). In summary, the current results suggest that the key events measured in the HA can be extrapolated with reasonable certainty to predict the ED50s for the adverse in utero effects of antiandrogenic chemicals on male rat offspring.
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Affiliation(s)
- Leon E Gray
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | | | - Christy S Lambright
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Nicola Evans
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Phillip C Hartig
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Mary C Cardon
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Vickie S Wilson
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Andrew K Hotchkiss
- HPASB, HEEAD, CPHEA, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Justin M Conley
- Reproductive and Developmental Toxicology Branch, PHITD, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
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13
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Li J, Tian J, Yin H, Peng Y, Liu S, Yao S, Zhang L. Chemical conjugation of FITC to track silica nanoparticles in vivo and in vitro: An emerging method to assess the reproductive toxicity of industrial nanomaterials. ENVIRONMENT INTERNATIONAL 2021; 152:106497. [PMID: 33714870 DOI: 10.1016/j.envint.2021.106497] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/02/2021] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
Previous studies have demonstrated that silica nanoparticle (SiNP) exposure induces pulmonary and cardiovascular diseases, yet their transportation and degradation in vivo have not been fully elucidated. From the perspective of reproduction, this study was implemented to examine the uterine accumulation of SiNP and explore its reproductive toxicity and pathogenic mechanisms. First, we coupled FITC onto SiNPs and intratracheally instilled them into pregnant mice on the fifth gestational day, and the toxic effect of SiNP was evaluated in vitro and in vivo. It was found that SiNP penetrated the trophoblast membrane, leading to apoptosis and suppression of cell proliferation, tube formation, and invasion in a dose-dependent manner. Mechanistically, SiNP dysregulated the expression of Scd1, Slc27a1, and Cpt1a, and induced over synthesis and efflux obstruction of fatty acid through the PPARγ signaling pathway. The downregulation of Caspase-3 triggered apoptosis of trophoblast, which was causally associated with intracellular fatty acid accumulation as revealed by the correlation analysis. Besides, SiNP induced uterine inflammation in vivo, which aggravated with the observation prolongation within 24 h. Overall, SiNPs were visualized by coupling with FITC, and the uterine accumulation of SiNP induced fatty acid metabolic disorder, biological dysfunction, and trophoblast apoptosis, which were mediated in part by the PPARγ signaling pathway. These findings would contribute to understanding the environmental impacts of SiNP better, as well as the development of control measures for environmental pollution.
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Affiliation(s)
- Junxia Li
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Maternal and Child Health Care Hospital of Shandong Province, Shandong University, Jinan 250001, China
| | - Jiaqi Tian
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Maternal and Child Health Care Hospital of Shandong Province, Shandong University, Jinan 250001, China
| | - Haoyu Yin
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Maternal and Child Health Care Hospital of Shandong Province, Shandong University, Jinan 250001, China
| | - Yanjie Peng
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Maternal and Child Health Care Hospital of Shandong Province, Shandong University, Jinan 250001, China
| | - Song Liu
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Maternal and Child Health Care Hospital of Shandong Province, Shandong University, Jinan 250001, China
| | - Sanqiao Yao
- School of Public Health, Xinxiang Medical University, Xinxiang 453000, China
| | - Lin Zhang
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Maternal and Child Health Care Hospital of Shandong Province, Shandong University, Jinan 250001, China.
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14
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Chen H, Xin X, Liu M, Ma F, Yu Y, Huang J, Dai H, Li Z, Ge RS. In utero exposure to dipentyl phthalate disrupts fetal and adult Leydig cell development. Toxicol Appl Pharmacol 2021; 419:115514. [PMID: 33798595 DOI: 10.1016/j.taap.2021.115514] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/23/2021] [Accepted: 03/27/2021] [Indexed: 01/20/2023]
Abstract
Phthalates as plasticizers are widely used in many consumer products. Dipentyl phthalate (DPeP) is one of phthalates. However, there are currently few data on whether DPeP exposure affects rat Leydig cell development. In this study, we investigated the effects of in utero DPeP exposure on Leydig cell development in the testes of male newborn and adult rats. From gestational days 14 to 21, Sprague-Dawley pregnant rats were gavaged vehicle (corn oil, control) or DPeP (10, 50, 100, and 500 mg/kg body weight/day). Testosterone and the expression of Leydig cell genes and proteins in the testis at birth and at postnatal day 56 were examined. DPeP dose-dependently reduced serum testosterone levels of male offspring at birth and at postnatal day 56 at 100 and 500 mg/kg and lowered serum luteinizing hormone levels at adult males at ≥10 mg/kg when compared with the control. In addition, DPeP increased number of fetal Leydig cells by inducing their proliferation but down-regulated the expression of Lhcgr, Scarb1, Star, Cyp11a1, Hsd3b1, Cyp17a1, Hsd17b3, and Insl3 in fetal Leydig cells per se. DPeP reduced number of adult Leydig cells by inducing cell apoptosis and down-regulated the expression of Lhcgr and Star in adult Leydig cells at postnatal day 56. DPeP lowered SIRT1 and BCL2 levels in the testis of adult rats. In conclusion, DPeP adversely affects both fetal and adult Leydig cell development after in utero exposure.
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Affiliation(s)
- Haiqiong Chen
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiu Xin
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Miaoqing Liu
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Feifei Ma
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yige Yu
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jie Huang
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Haipeng Dai
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhongrong Li
- Department of Pediatrics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Ren-Shan Ge
- Department of Anesthesiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
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15
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Morová M, Kršková L. Autistic-like traits in laboratory rodents exposed to phthalic acid esters during early development - an animal model of autism? Physiol Res 2021; 70:345-361. [PMID: 33982578 DOI: 10.33549/physiolres.934570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Phthalates are chemical substances that are widely used to provide flexibility and durability to plastic materials. They leach from products in which they are mixed and reach living organisms. Results from experimental studies suggest that exposure to phthalates can have a negative impact on an individual's neuronal system and behavior. In this regard, exposure during early ontogenesis seems to be particularly dangerous due to the extensive growth and development of body structures and functions. Disruption during this critical time can result in alterations of behavior and the emergence of neurodevelopmental disorders, such as autism spectrum disorder (ASD). Various animal models have been used to elucidate the pathogenesis of this disease. They are fundamental for research, and although the translation of results to humans is difficult, new animal models are being developed. The aim of this review is to summarize laboratory rodent studies in which early developmental phthalate exposure resulted in brain alterations and autistic-like behavioral traits. We also discuss the possibility of using early developmental phthalate exposure in rodents to create a new animal model of autism.
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Affiliation(s)
- M Morová
- Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University in Bratislava, Bratislava 4, Slovak Republic.
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16
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Draskau MK, Lardenois A, Evrard B, Boberg J, Chalmel F, Svingen T. Transcriptome analysis of fetal rat testis following intrauterine exposure to the azole fungicides triticonazole and flusilazole reveals subtle changes despite adverse endocrine effects. CHEMOSPHERE 2021; 264:128468. [PMID: 33032228 DOI: 10.1016/j.chemosphere.2020.128468] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/11/2020] [Accepted: 09/26/2020] [Indexed: 06/11/2023]
Abstract
Azoles are used in agriculture and medicine to combat fungal infections. We have previously examined the endocrine disrupting properties of the agricultural azole fungicides triticonazole and flusilazole. Triticonazole displayed strong androgen receptor (AR) antagonism in vitro, whereas in utero exposure resulted in anti-androgenic effects in vivo evidenced by shorter anogenital distance (AGD) in fetal male rats. Flusilazole displayed strong AR antagonism, but less potent than triticonazole, and disrupted steroidogenesis in vitro, whereas in utero exposure disrupted fetal male plasma hormone levels. To elaborate on how these azole fungicides can disrupt male reproductive development by different mechanisms, and to investigate whether feminization effects such as short AGD in males can also be detected at the transcript level in fetal testes, we profiled fetal testis transcriptomes after in utero exposure to triticonazole and flusilazole by 3'Digital Gene Expression (3'DGE). The analysis revealed few transcriptional changes after exposure to either compound at gestation day 17 and 21. This suggests that the observed influence of flusilazole on hormone production may be by directly targeting steroidogenic enzyme activity in the testis at the protein level, whereas observations of shorter AGD by triticonazole may primarily be due to disturbed androgen signaling in androgen-sensitive tissues. Expression of Calb2 and Gsta2 was altered by flusilazole but not triticonazole and may pinpoint novel pathways of disrupted testicular steroid synthesis. Our findings have wider implication for how we integrate omics data in chemical testing frameworks, including selection of non-animal test methods and building of Adverse Outcome Pathways for regulatory purposes.
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Affiliation(s)
- Monica Kam Draskau
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kongens Lyngby, DK 2800, Denmark
| | - Aurélie Lardenois
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail), UMR_S 1085, F-35000, Rennes, France
| | - Bertrand Evrard
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail), UMR_S 1085, F-35000, Rennes, France
| | - Julie Boberg
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kongens Lyngby, DK 2800, Denmark
| | - Frédéric Chalmel
- Univ Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail), UMR_S 1085, F-35000, Rennes, France
| | - Terje Svingen
- Division of Diet, Disease Prevention and Toxicology, National Food Institute, Technical University of Denmark, Kemitorvet Building 202, Kongens Lyngby, DK 2800, Denmark.
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17
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Chen H, Chen K, Qiu X, Xu H, Mao G, Zhao T, Feng W, Okeke ES, Wu X, Yang L. The reproductive toxicity and potential mechanisms of combined exposure to dibutyl phthalate and diisobutyl phthalate in male zebrafish (Danio rerio). CHEMOSPHERE 2020; 258:127238. [PMID: 32563064 DOI: 10.1016/j.chemosphere.2020.127238] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 05/25/2020] [Accepted: 05/26/2020] [Indexed: 06/11/2023]
Abstract
Dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP) are phthalate compounds frequently detected in the environment. Despite increasing awareness of their toxicity in human and animals, the male reproductive toxicity of their combined exposure remains elusive. The purposes of this study were to investigate whether combined exposure to DBP and DiBP could induce male reproductive toxicity, and to explore the potential toxicological mechanisms. Adult male zebrafish were exposed to DBP (11, 113 and 1133 μg L-1), DiBP (10, 103 and 1038 μg L-1) and their mixtures (Mix) (11 + 10, 113 + 103, 1133 + 1038 μg L-1) for 30 days, and their effects on plasma hormone secretion, testis histology and transcriptomics were examined. Highest concentrations of Mix exposure caused greater imbalance ratio of T/E2 and more severe structural damage to testis than single exposure. These effects were consistent with the testis transcriptome analysis for which 4570 genes were differentially expressed in Mix exposure, while 2795 and 1613 genes were differentially expressed in DBP and DiBP, respectively. KEGG pathway analysis showed that both single and combined exposure of DBP and DiBP could affect cytokine-cytokine receptor interaction. The difference was that combined exposure could also affect steroid hormone synthesis, extracellular matrix receptor interaction, retinol metabolism, and PPAR signaling pathways. These results demonstrated that combined exposure to DBP and DiBP could disrupt spermatogenesis and elicit male reproductive toxicity in zebrafish.
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Affiliation(s)
- Hui Chen
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Kun Chen
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Xuchun Qiu
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Hai Xu
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Guanghua Mao
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Ting Zhao
- School of the Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Weiwei Feng
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Emmanuel Sunday Okeke
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Xiangyang Wu
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China.
| | - Liuqing Yang
- School of the Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
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18
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Systematic comparison of the male reproductive tract in fetal and adult Wistar rats exposed to DBP and DINP in utero during the masculinisation programming window. Toxicol Lett 2020; 335:37-50. [PMID: 33086118 DOI: 10.1016/j.toxlet.2020.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 12/30/2022]
Abstract
This study investigates possible effects of in utero exposure of rats to a low dose (125 mg/kg bw/day) and a high dose (750 mg/kg bw/day) of Diisononyl phthalate (DINP) during the masculinisation programming window (MPW) which is embryonic days 15.5-18.5 (e15.5 - e18.5). Dibutyl phthalate (DBP) was used at a high dose level (750 mg/kg bw/day) as an established positive control substance for anti-androgenic effects on the developing male reproductive tract. We focussed on the MPW and measured a multitude of biological endpoints at various life stages and applied state of the art histopathology staining techniques to refine the characterization of potential changes to the testis, beyond what is currently available with DINP. If DINP can mediate testicular dysgenesis (TDS) disorders, this exposure window would be sufficient to induce androgen impacts and alter male reproductive tract development as shown earlier in this validated experimental model with DBP. Overall, the results of this systematic comparison provide convincing evidence on the differences between the effects occurring with DBP and DINP. In contrast to what was seen with DBP, DINP did not cause cryptorchidism or hypospadias, had no effect on anogenital distance/anogenital index (AGD/AGi) and Leydig cell aggregates on e17.5 and e21.5 did not increase. With DINP no reduction of intratesticular testosterone, no effects on sperm motility and sperm count and no effect on adult testosterone or luteinizing hormone (LH) levels were seen. Our results demonstrate that DINP does not cause the adverse reproductive effects known to occur with DBP, a well-established endocrine disruptor.
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Dekant W. Grouping of phthalates for risk characterization of human exposures. Toxicol Lett 2020; 330:1-6. [PMID: 32389706 DOI: 10.1016/j.toxlet.2020.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/28/2020] [Accepted: 05/03/2020] [Indexed: 10/24/2022]
Abstract
The European Food Safety Authority (EFSA) has developed a group tolerable daily intake (TDI) for low molecular weight phthalates (LWP) including diisononyl phthalate (DINP). The LWP covered by the group TDI induce clear adverse effects on rat testicular development and pronounced reductions in fetal testicular testosterone. In contrast, DINP has a very low potency regarding changes in testicular testosterone in fetal rodents and does not induce adverse effects on reproductive endpoints. The most sensitive toxicity endpoint for DINP is liver toxicity. Due to the much lower potency of DINP for effects on testosterone, absence of reproductive toxicity, and its noted liver toxicity as compared to the LWP in the group, DINP should not be included in the group TDI.
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Affiliation(s)
- Wolfgang Dekant
- Department of Toxicology, University of Würzburg, Versbacher Strasse 9, 97078 Würzburg, Germany.
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20
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Zhang S, Chen X, Li X, Wang Y, Zhu Q, Huang T, Ge RS. Effects of in utero exposure to diisodecyl phthalate on fetal testicular cells in rats. Toxicol Lett 2020; 330:23-29. [PMID: 32387388 DOI: 10.1016/j.toxlet.2020.04.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 03/18/2020] [Accepted: 04/29/2020] [Indexed: 02/06/2023]
Abstract
Diisodecyl phthalate (DIDP) is one of synthetic phthalate plasticizers. It is widely used in plastic products and is a potential endocrine disruptor. However, the effects of DIDP on fetal testicular cell development remain unclear. The objective of the present study was to determine the effects of DIDP on fetal testis development in rats after in utero exposure. Sprague Dawley dams were randomly divided into 5 groups and were daily gavaged with DIDP (0, 10, 100, 500, and 1000 mg/kg body weight) from gestational day 14-21. Serum testosterone levels, fetal Leydig cell number and distribution, testicular gene and protein expression in male pups were examined. DIDP decreased serum testosterone levels at 1000 mg/kg (1.37 ± 0.40 ng/mL, mean ± SE) when compared to the control level (3.14 ± 0.60 ng/mL). DIDP did not affect numbers of Leydig and Sertoli cells. DIDP significantly induced abnormal aggregation of fetal Leydig cells and increased the incidence of multinucleated gonocytes at 1000 mg/kg. Furthermore, DIDP down-regulated expression of Star, Cyp11a1, Hsd17b3, and Insl3 in fetal Leydig cells at 1000 mg/kg and Sox9 in Sertoli cells at 1000 mg/kg. In conclusion, the current study indicates that in utero exposure to high-dose DIDP disrupts the development of fetal testicular cells, thus affecting the male reproductive system.
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Affiliation(s)
- Song Zhang
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Xiuxiu Chen
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Xiaoheng Li
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Yiyan Wang
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Qiqi Zhu
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Tongliang Huang
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Ren-Shan Ge
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China.
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21
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Gao HT, Di QN, Qian LL, Lu L, Li RX, Cao WX, Xu Q. Zinc supplement ameliorates phthalates-induced reproductive toxicity in male rats. CHEMOSPHERE 2020; 246:125828. [PMID: 31927381 DOI: 10.1016/j.chemosphere.2020.125828] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 12/12/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
People are inevitably exposed to phthalates (PEs) ubiquitously existing in environment. Our previous studies, simulating the actual situations of people exposure to PEs, have shown that the sub-chronic exposure to low-doses PEs mixture (MIXPs) impaired reproductive function in male rats. Zinc is an important element in maintaining male reproductive functions. However, it is still unknown whether zinc supplement could mitigate PEs-induced male reproductive toxicity or not with sub-chronic low-dose mixture exposure. This study aimed to explore the effect of zinc supplement on the reproductive toxicity caused by sub-chronic MIXPs exposure (160 mg/(kg•body weight)/d, for 90 days) in male rats, and further to reveal the underlying mechanisms. Testosterone (T), FSH and LH in serum, early toxicity indicators in urine, PIWI proteins (PIWIL1 and PIWIL2) expression in testes and pathological examination were performed for toxicity evaluation. Steroidogenic proteins (17β-HSD, StAR, CYP17A1, P450scc and SRD5A) were measured for mechanisms of exploration. The results indicated that zinc supplement could inhibit the T, LH, FSH level decreases in serum, abolish the effect of 5 early toxicity indicators' levels in urine, restrain the alteration of PIWI proteins expression and improve the constructional injury of testes. These effects might be relevant with the suppressed alteration of the expression of steroidogenic proteins induced by MIXPs in rat testicular cells. This work may offer further insights into reducing health risks of MIXPs exposure.
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Affiliation(s)
- Hai-Tao Gao
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, 210009, China; Department of Preventive Medicine, School of Public Health and Management, Wenzhou Medical University, Wenzhou, 325035, China
| | - Qian-Nan Di
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, 210009, China
| | - Liang-Liang Qian
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, 210009, China
| | - Lingeng Lu
- Department of Chronic Disease Epidemiology, Yale School of Public Health, School of Medicine, Yale University, 60 College Street, New Haven, CT, 06520-8034, USA
| | - Rui-Xian Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, 210009, China
| | - Wei-Xin Cao
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, 210009, China
| | - Qian Xu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, 210009, China.
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22
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Spade DJ, Hall SJ, Wortzel JD, Reyes G, Boekelheide K. All-trans Retinoic Acid Disrupts Development in Ex Vivo Cultured Fetal Rat Testes. II: Modulation of Mono-(2-ethylhexyl) Phthalate Toxicity. Toxicol Sci 2020; 168:149-159. [PMID: 30476341 DOI: 10.1093/toxsci/kfy283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Humans are universally exposed to low levels of phthalate esters (phthalates), which are used to plasticize polyvinyl chloride. Phthalates exert adverse effects on the development of seminiferous cords in the fetal testis through unknown toxicity pathways. To investigate the hypothesis that phthalates alter seminiferous cord development by disrupting retinoic acid (RA) signaling in the fetal testis, gestational day 15 fetal rat testes were exposed for 1-3 days to 10-6 M all-trans retinoic acid (ATRA) alone or in combination with 10-6-10-4 M mono-(2-ethylhexyl) phthalate (MEHP) in ex vivo culture. As previously reported, exogenous ATRA reduced seminiferous cord number. This effect was attenuated in a concentration-dependent fashion by MEHP co-exposure. ATRA and MEHP-exposed testes were depleted of DDX4-positive germ cells but not Sertoli cells. MEHP alone enhanced the expression of the RA receptor target Rbp1 and the ovary development-associated genes Wnt4 and Nr0b1, and suppressed expression of the Leydig cell marker, Star, and the germ cell markers, Ddx4 and Pou5f1. In co-exposures, MEHP predominantly enhanced the gene expression effects of ATRA, but the Wnt4 and Nr0b1 concentration-responses were nonlinear. Similarly, ATRA increased the number of cells expressing the granulosa cell marker FOXL2 in testis cultures, but this induction was attenuated by addition of MEHP. These results indicate that MEHP can both enhance and inhibit actions of ATRA during fetal testis development and provide evidence that RA signaling is a target for phthalate toxicity in the fetal testis.
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Affiliation(s)
- Daniel J Spade
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02912
| | - Susan J Hall
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02912
| | - Jeremy D Wortzel
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02912
| | - Gerardo Reyes
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02912.,Division of Natural Sciences, College of Mount Saint Vincent, Riverdale, New York 10471
| | - Kim Boekelheide
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02912
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23
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Gray LE, Furr JR, Conley JM, Lambright CS, Evans N, Cardon MC, Wilson VS, Foster PM, Hartig PC. A Conflicted Tale of Two Novel AR Antagonists In Vitro and In Vivo: Pyrifluquinazon Versus Bisphenol C. Toxicol Sci 2020; 168:632-643. [PMID: 30649549 DOI: 10.1093/toxsci/kfz010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Chemicals that disrupt androgen receptor (AR) function in utero induce a cascade of adverse effects in male rats including reduced anogenital distance, retained nipples, and reproductive tract malformations. The objective of this study was to compare the in vitro and in utero activities of two novel AR antagonists, bisphenol C (BPC) and pyrifluquinazon (PFQ). In vitro, BPC was as potent an AR antagonist as hydroxyflutamide. Furthermore, BPC inhibited fetal testis testosterone production and testis gene expression ex vivo. However, when BPC was administered at 100 and 200 mg/kg/d in utero, the reproductive tract of the male offspring was minimally affected. None of the males displayed reproductive malformations. For comparison, in utero administration of flutamide has been shown to induce malformations in 100% of males at 6 mg/kg/d. In vitro, PFQ was several orders of magnitude less potent than BPC, vinclozolin, or procymidone. However, in utero administration of 12.5, 25, 50, and 100 mg PFQ/kg/d on GD 14-18 induced antiandrogenic effects at all dosage levels and 91% of the males displayed reproductive malformation in the high dose group. Overall, BPC was ∼380-fold more potent than PFQ in vitro, whereas PFQ was far more potent than BPC in utero. Incorporating toxicokinetic and toxicodynamic data into in vitro to in vivo extrapolations would reduce the discordance between the in vitro and in utero effects of PFQ and BPC and combining in vitro results with a short-term Hershberger assay would reduce the uncertainty in predicting the in utero effects of antiandrogenic chemicals.
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Affiliation(s)
- Leon Earl Gray
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | | | - Justin M Conley
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Christy S Lambright
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Nicola Evans
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Mary C Cardon
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | - Vickie S Wilson
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
| | | | - Phillip C Hartig
- Reproductive Toxicology Branch, Toxicology Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina 27711
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24
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Di Lorenzo M, Winge SB, Svingen T, De Falco M, Boberg J. Intrauterine exposure to diethylhexyl phthalate disrupts gap junctions in the fetal rat testis. Curr Res Toxicol 2020; 1:5-11. [PMID: 34345832 PMCID: PMC8320622 DOI: 10.1016/j.crtox.2020.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 02/08/2023] Open
Abstract
Fetal exposure to certain phthalate esters can disrupt testis development in rodents and lead to male reproductive disorders, but with a causal link less certain in humans. Di(2-ethylhexyl) phthalate (DEHP) is one of the most common phthalates found in the environment and in rodents it is known to induce serious testis toxicity, as well as male reproductive disorders including cryptorchidism, hypospadias, impaired spermatogenesis and reduced fertility. In this study, we show that perinatal DEHP exposure disrupts gap junction localization in fetal and postnatal rat testis and correlate these findings to morphological changes. The protein Connexin 43 (CX43), normally expressed strongly in testicular gap junctions, was markedly downregulated in Leydig cells of DEHP-exposed fetal testes. In the postnatal testes, CX43 expression was recovered in the DEHP-exposed animals, even though Leydig cell clusters and malformed cords with intratubular Leydig cells were still present. DEHP disrupts gap junction localization in fetal and postnatal rat testis. DEHP exposure reduces Cx43-positive gap junctions in Leydig cell clusters in fetal rat testis. Leydig cell gap junctions recover in postnatal testis after early life DEHP exposure.
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Affiliation(s)
| | - Sofia Boeg Winge
- 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
| | - Maria De Falco
- Department of Biology, University Federico II of Naples, Naples, Italy.,National Institute of Biostructures and Biosystems (INBB), Rome, Italy
| | - 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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25
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Krewski D, Andersen ME, Tyshenko MG, Krishnan K, Hartung T, Boekelheide K, Wambaugh JF, Jones D, Whelan M, Thomas R, Yauk C, Barton-Maclaren T, Cote I. Toxicity testing in the 21st century: progress in the past decade and future perspectives. Arch Toxicol 2019; 94:1-58. [DOI: 10.1007/s00204-019-02613-4] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 11/05/2019] [Indexed: 12/19/2022]
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26
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Silano V, Barat Baviera JM, Bolognesi C, Chesson A, Cocconcelli PS, Crebelli R, Gott DM, Grob K, Lampi E, Mortensen A, Rivière G, Steffensen I, Tlustos C, Van Loveren H, Vernis L, Zorn H, Cravedi J, Fortes C, Tavares Poças MDF, Waalkens‐Berendsen I, Wölfle D, Arcella D, Cascio C, Castoldi AF, Volk K, Castle L. Update of the risk assessment of di-butylphthalate (DBP), butyl-benzyl-phthalate (BBP), bis(2-ethylhexyl)phthalate (DEHP), di-isononylphthalate (DINP) and di-isodecylphthalate (DIDP) for use in food contact materials. EFSA J 2019; 17:e05838. [PMID: 32626195 PMCID: PMC7008866 DOI: 10.2903/j.efsa.2019.5838] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP Panel) was asked by the European Commission to update its 2005 risk assessments of di-butylphthalate (DBP), butyl-benzyl-phthalate (BBP), bis(2-ethylhexyl)phthalate (DEHP), di-isononylphthalate (DINP) and di-isodecylphthalate (DIDP), which are authorised for use in plastic food contact material (FCM). Dietary exposure estimates (mean and high (P95)) were obtained by combining literature occurrence data with consumption data from the EFSA Comprehensive Database. The highest exposure was found for DINP, ranging from 0.2 to 4.3 and from 0.4 to 7.0 μg/kg body weight (bw) per day for mean and high consumers, respectively. There was not enough information to draw conclusions on how much migration from plastic FCM contributes to dietary exposure to phthalates. The review of the toxicological data focused mainly on reproductive effects. The CEP Panel derived the same critical effects and individual tolerable daily intakes (TDIs) (mg/kg bw per day) as in 2005 for all the phthalates, i.e. reproductive effects for DBP (0.01), BBP (0.5), DEHP (0.05), and liver effects for DINP and DIDP (0.15 each). Based on a plausible common mechanism (i.e. reduction in fetal testosterone) underlying the reproductive effects of DEHP, DBP and BBP, the Panel considered it appropriate to establish a group-TDI for these phthalates, taking DEHP as index compound as a basis for introducing relative potency factors. The Panel noted that DINP also affected fetal testosterone levels at doses around threefold higher than liver effects and therefore considered it conservative to include it within the group-TDI which was established to be 50 μg/kg bw per day, expressed as DEHP equivalents. The aggregated dietary exposure for DBP, BBP, DEHP and DINP was estimated to be 0.9-7.2 and 1.6-11.7 μg/kg bw per day for mean and high consumers, respectively, thus contributing up to 23% of the group-TDI in the worst-case scenario. For DIDP, not included in the group-TDI, dietary exposure was estimated to be always below 0.1 μg/kg bw per day and therefore far below the TDI of 150 μg/kg bw per day. This assessment covers European consumers of any age, including the most sensitive groups. Based on the limited scope of the mandate and the uncertainties identified, the Panel considered that the current assessment of the five phthalates, individually and collectively, should be on a temporary basis.
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Belcher SM, Cline JM, Conley J, Groeters S, Jefferson WN, Law M, Mackey E, Suen AA, Williams CJ, Dixon D, Wolf JC. Endocrine Disruption and Reproductive Pathology. Toxicol Pathol 2019; 47:1049-1071. [PMID: 31833458 PMCID: PMC8008741 DOI: 10.1177/0192623319879903] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
During the past 20 years, investigations involving endocrine active substances (EAS) and reproductive toxicity have dominated the landscape of ecotoxicological research. This has occurred in concert with heightened awareness in the scientific community, general public, and governmental entities of the potential consequences of chemical perturbation in humans and wildlife. The exponential growth of experimentation in this field is fueled by our expanding knowledge into the complex nature of endocrine systems and the intricacy of their interactions with xenobiotic agents. Complicating factors include the ever-increasing number of novel receptors and alternate mechanistic pathways that have come to light, effects of chemical mixtures in the environment versus those of single EAS laboratory exposures, the challenge of differentiating endocrine disruption from direct cytotoxicity, and the potential for transgenerational effects. Although initially concerned with EAS effects chiefly in the thyroid glands and reproductive organs, it is now recognized that anthropomorphic substances may also adversely affect the nervous and immune systems via hormonal mechanisms and play substantial roles in metabolic diseases, such as type 2 diabetes and obesity.
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Affiliation(s)
| | - J. Mark Cline
- Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | | | | | | | - Mac Law
- North Carolina State College of Veterinary Medicine, Raleigh, NC, USA
| | - Emily Mackey
- Michigan State University, East Lansing, MI, USA
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28
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Gutiérrez-García AK, Choudhury M, De Leon-Rodriguez A. Diisononyl Phthalate Differentially Affects Sirtuin Expression in the HepG2 Cell Line. Chem Res Toxicol 2019; 32:1863-1870. [DOI: 10.1021/acs.chemrestox.9b00206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Ana K. Gutiérrez-García
- División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, A.C., Camino a la Presa San José 2055, Col. Lomas 4a Sección, C.P. 78216 San Luis Potosí, SLP México
| | - Mahua Choudhury
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy, Texas A&M Health Science Center, College Station, Texas 78363, United States
| | - Antonio De Leon-Rodriguez
- División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, A.C., Camino a la Presa San José 2055, Col. Lomas 4a Sección, C.P. 78216 San Luis Potosí, SLP México
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29
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Baken KA, Lambrechts N, Remy S, Mustieles V, Rodríguez-Carrillo A, Neophytou CM, Olea N, Schoeters G. A strategy to validate a selection of human effect biomarkers using adverse outcome pathways: Proof of concept for phthalates and reproductive effects. ENVIRONMENTAL RESEARCH 2019; 175:235-256. [PMID: 31146096 DOI: 10.1016/j.envres.2019.05.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/09/2019] [Accepted: 05/10/2019] [Indexed: 05/21/2023]
Abstract
Human biomonitoring measures the concentrations of environmental chemicals or their metabolites in body fluids or tissues. Complementing exposure biomarkers with mechanistically based effect biomarkers may further elucidate causal pathways between chemical exposure and adverse health outcomes. We combined information on effect biomarkers previously implemented in human observational studies with mechanisms of action reported in experimental studies and with information from published Adverse Outcome Pathways (AOPs), focusing on adverse reproductive effects of phthalate exposure. Phthalates constitute a group of chemicals that are ubiquitous in consumer products and have been related to a wide range of adverse health effects. As a result of a comprehensive literature search, we present an overview of effect biomarkers for reproductive toxicity that are substantiated by mechanistic information. The activation of several receptors, such as PPARα, PPARγ, and GR, may initiate events leading to impaired male and female fertility as well as other adverse effects of phthalate exposure. Therefore, these receptors appear as promising targets for the development of novel effect biomarkers. The proposed strategy connects the fields of epidemiology and toxicology and may strengthen the weight of evidence in observational studies that link chemical exposures to health outcomes.
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Affiliation(s)
- Kirsten A Baken
- Unit Health, Flemish Institute for Technological Research (VITO NV), Mol, Belgium.
| | - Nathalie Lambrechts
- Unit Health, Flemish Institute for Technological Research (VITO NV), Mol, Belgium
| | - Sylvie Remy
- Unit Health, Flemish Institute for Technological Research (VITO NV), Mol, Belgium; Department of Epidemiology and Social Medicine, University of Antwerp, Antwerp, Belgium
| | - Vicente Mustieles
- Biosanitary Research Institute of Granada (ibs.GRANADA), University Hospitals of Granada, Granada, Spain; Center for Biomedical Research (CIBM), University of Granada, Granada, Spain; Consortium for Biomedical Research in Epidemiology & Public Health (CIBERESP), Spain
| | | | - Christiana M Neophytou
- Department of Biological Sciences, School of Pure and Applied Sciences, University of Cyprus, Nicosia, Cyprus
| | - Nicolas Olea
- Biosanitary Research Institute of Granada (ibs.GRANADA), University Hospitals of Granada, Granada, Spain; Center for Biomedical Research (CIBM), University of Granada, Granada, Spain; Consortium for Biomedical Research in Epidemiology & Public Health (CIBERESP), Spain
| | - Greet Schoeters
- Unit Health, Flemish Institute for Technological Research (VITO NV), Mol, Belgium; Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Department of Environmental Medicine, Institute of Public Health, University of Southern Denmark, Odense, Denmark
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30
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Arzuaga X, Walker T, Yost EE, Radke EG, Hotchkiss AK. Use of the Adverse Outcome Pathway (AOP) framework to evaluate species concordance and human relevance of Dibutyl phthalate (DBP)-induced male reproductive toxicity. Reprod Toxicol 2019; 96:445-458. [PMID: 31260805 PMCID: PMC10067323 DOI: 10.1016/j.reprotox.2019.06.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 06/05/2019] [Accepted: 06/25/2019] [Indexed: 12/14/2022]
Abstract
Dibutyl phthalate (DBP) is a phthalate ester used as a plasticizer, and solvent. Studies using rats consistently report that DBP exposure disrupts normal development of the male reproductive system in part via inhibition of androgen synthesis. However, studies using xenograft models report that in human fetal testis DBP exposure is unlikely to impair testosterone synthesis. These results question the validity of the rat model for assessment of male reproductive effects caused by DBP. The Adverse Outcome Pathway (AOP) framework was used to evaluate the available evidence for DBP-induced toxicity to the male reproductive system. Three relevant biological elements were identified: 1) fetal rats are more sensitive than other rodents and human fetal xenografts to DBP-induced anti-androgenic effects, 2) DBP-induced androgen-independent adverse outcomes are conserved amongst different mammalian models and human fetal testis xenografts, and 3) DBP-induced anti-androgenic effects are conserved in different mammalian species when exposure occurs during postnatal life stages.
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Affiliation(s)
- Xabier Arzuaga
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America.
| | - Teneille Walker
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
| | - Erin E Yost
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
| | - Elizabeth G Radke
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
| | - Andrew K Hotchkiss
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
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Carnevali O, Santobuono M, Forner-Piquer I, Randazzo B, Mylonas CC, Ancillai D, Giorgini E, Maradonna F. Dietary diisononylphthalate contamination induces hepatic stress: a multidisciplinary investigation in gilthead seabream (Sparus aurata) liver. Arch Toxicol 2019; 93:2361-2373. [PMID: 31230093 DOI: 10.1007/s00204-019-02494-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 06/17/2019] [Indexed: 02/07/2023]
Abstract
In this study, adult gilthead seabream (Sparus aurata) were exposed for 21 days to Di-iso-nonylphthalte (DiNP at 15 and 1500 μg kg-1 bw day-1) via the diet. This plastic additive has been recently introduced to replace the di-(2-ethylhexyl)phthalate, the toxicity of which has been demonstrated conclusively both in vivo and in vitro trials. An analysis of a set of biomarkers involved in stress and immune response provides evidence of hepatic toxicity by DiNP in the present study. Both hsp70 and gr mRNA levels were upregulated significantly by DiNP, while plasma cortisol increased only in fish fed with the lowest DiNP dose. The oxidative stress markers g6pdh, glut red, gpx1 and CAT were upregulated by DiNP; gst mRNA was induced by the high dose and gck mRNA was downregulated significantly by the low dose. The mRNA levels of genes involved in the immune response, such as pla2, 5-lox, tnfa and cox2, were upregulated significantly only by the high dose of DiNP, while il1 mRNA increases in both doses. These molecular evidences were complemented with features obtained by Fourier Transform Infrared Imaging (FTIRI) analysis regarding the hepatic distribution of the main biological macromolecules. The FTIRI analysis showed an alteration of biochemical composition in DiNP samples. In particular, the low dose of DiNP induced an increase of saturated and unsaturated lipids and phosphorylated proteins, and a decrease of glycogen levels. The levels of caspase did not change significantly in the study, suggesting that DiNP does not activate apoptosis. Finally, the results also suggested the onset of hepatic oxidative stress and the activation of immune response, adding new knowledge to the already described hepatic DiNP toxicity.
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Affiliation(s)
- Oliana Carnevali
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Martina Santobuono
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Isabel Forner-Piquer
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Basilio Randazzo
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Constantinos C Mylonas
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Center for Marine Research, P.O. Box 2214, 71003, Heraklion, Crete, Greece
| | - Daniele Ancillai
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Elisabetta Giorgini
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Francesca Maradonna
- Dipartimento Scienze Della Vita e dell'Ambiente, Università Politecnica Delle Marche, Via Brecce Bianche, 60131, Ancona, Italy.
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Yost EE, Euling SY, Weaver JA, Beverly BEJ, Keshava N, Mudipalli A, Arzuaga X, Blessinger T, Dishaw L, Hotchkiss A, Makris SL. Hazards of diisobutyl phthalate (DIBP) exposure: A systematic review of animal toxicology studies. ENVIRONMENT INTERNATIONAL 2019; 125:579-594. [PMID: 30591249 PMCID: PMC8596331 DOI: 10.1016/j.envint.2018.09.038] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 08/30/2018] [Accepted: 09/23/2018] [Indexed: 05/19/2023]
Abstract
BACKGROUND Biomonitoring studies indicate a trend towards increased human exposure to diisobutyl phthalate (DIBP), a replacement for dibutyl phthalate (DBP). Recent reviews have found DIBP to be a male reproductive toxicant, but have not evaluated other hazards of DIBP exposure. OBJECTIVE To inform chemical risk assessment, we performed a systematic review to identify and characterize outcomes within six broad hazard categories (male reproductive, female reproductive, developmental, liver, kidney, and cancer) following exposure of nonhuman mammalian animals to DIBP or the primary metabolite, monoisobutyl phthalate (MIBP). METHODS A literature search was conducted in four online scientific databases [PubMed, Web of Science, Toxline, and Toxic Substances Control Act Test Submissions 2.0 (TSCATS2)], and augmented by review of regulatory sources as well as forward and backward searches. Studies were identified for inclusion based on defined PECO (Population, Exposure, Comparator, Outcome) criteria. Studies were evaluated using criteria defined a priori for reporting quality, risk of bias, and sensitivity using a domain-based approach. Evidence was synthesized by outcome and life stage of exposure, and strength of evidence was summarized into categories of robust, moderate, slight, indeterminate, or compelling evidence of no effect, using a structured framework. RESULTS Nineteen toxicological studies in rats or mice met the inclusion criteria. There was robust evidence that DIBP causes male reproductive toxicity. Male rats and mice exposed to DIBP during gestation had decreased testosterone and adverse effects on sperm or testicular histology, with additional phthalate syndrome effects observed in male rats. There was also evidence of androgen-dependent and -independent male reproductive effects in rats and mice following peripubertal or young adult exposure to DIBP or MIBP, but confidence was reduced because of concerns over risk of bias and sensitivity in the available studies. There was also robust evidence that DIBP causes developmental toxicity; specifically, increased post-implantation loss and decreased pre- and postnatal growth. For other hazards, evidence was limited by the small number of studies, experimental designs that were suboptimal for evaluating outcomes, and study evaluation concerns such as incomplete reporting of methods and results. There was slight evidence for female reproductive toxicity and effects on liver, and indeterminate evidence for effects on kidney and cancer. CONCLUSION Results support DIBP as a children's health concern and indicate that male reproductive and developmental toxicities are hazards of DIBP exposure, with some evidence for female reproductive and liver toxicity. Data gaps include the need for more studies on male reproductive effects following postnatal and adult exposure, and studies to characterize potential hormonal mechanisms in females.
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Affiliation(s)
- Erin E Yost
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America.
| | - Susan Y Euling
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
| | - James A Weaver
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
| | - Brandiese E J Beverly
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
| | - Nagalakshmi Keshava
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
| | - Anuradha Mudipalli
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
| | - Xabier Arzuaga
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
| | - Todd Blessinger
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
| | - Laura Dishaw
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
| | - Andrew Hotchkiss
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Research Triangle Park, NC, United States of America
| | - Susan L Makris
- U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, United States of America
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Carnevali O, Giorgini E, Canuti D, Mylonas CC, Forner-Piquer I, Maradonna F. Diets contaminated with Bisphenol A and Di-isononyl phtalate modify skeletal muscle composition: A new target for environmental pollutant action. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 658:250-259. [PMID: 30577020 DOI: 10.1016/j.scitotenv.2018.12.134] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/02/2018] [Accepted: 12/09/2018] [Indexed: 06/09/2023]
Abstract
In the last years, an increasing number of studies reported that food pollution represents a significant route of exposure to environmental toxicants, able to cause mild to severe food illnesses and health problems, including hormonal and metabolic diseases. Pollutants can accumulate in organisms and biomagnify along the food web, finally targeting top consumers causing health and economic problems. In this study, adults of gilthead sea bream, Sparus aurata, were fed with diets contaminated with Bisphenol A (BPA) (4 and 4000 μg BPA kg-1 bw day-1) and Di-isononyl phthalate (DiNP) (15 and 1500 μg DiNP kg-1 bw day-1), to evaluate the effects of the contamination on the muscle macromolecular composition and alterations of its texture. The analysis conducted in the muscle using infrared microspectroscopy, molecular biology and biochemical assays, showed, in fish fed BPA contaminated diets, a decrease of unsaturated lipids and an increase of triglycerides and saturated alkyl chains. Conversely, in fish fed DiNP, a decrease of lipid content, caused by a reduction of both saturated and unsaturated chains and triglycerides was measured. Protein content was decreased by both xenobiotics evidencing a novel macromolecular target affected by these environmental contaminants. In addition, in all treated groups, proteins resulted more phosphorylated than in controls. Calpain and cathepsin levels, orchestrating protein turnover, were deregulated by both xenobiotics, evidencing alterations of muscle composition and texture. In conclusion, the results obtained suggest the ability of BPA and DiNP to modify the muscle macromolecular building, advising this tissue as a target of Endocrine-Disrupting Chemicals (EDCs) and providing a set of biomarkers as possible monitoring endpoints to develop novel OEDC test guidelines.
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Affiliation(s)
- Oliana Carnevali
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, 60131 Ancona, Italy; Istituto Nazionale Biostrutture e Biosistemi (INBB), Consorzio Interuniversitario, 00136 Roma, Italy
| | - Elisabetta Giorgini
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, 60131 Ancona, Italy
| | - Debora Canuti
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, 60131 Ancona, Italy
| | - Constantinos C Mylonas
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Center for Marine Research, P.O. Box 2214, Heraklion, Crete 71003, Greece
| | - Isabel Forner-Piquer
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, 60131 Ancona, Italy
| | - Francesca Maradonna
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, 60131 Ancona, Italy; Istituto Nazionale Biostrutture e Biosistemi (INBB), Consorzio Interuniversitario, 00136 Roma, Italy.
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Ma X, Yang J, Jia H, Li X, Wang D, Fu H, Yuan J, Li Y, Zheng G, Huang X. Androgenic/antiandrogenic activities of PAEs determined by a novel AR-mediated reporter gene assay based on LLC-MK2 cells. Toxicol Res (Camb) 2019; 8:522-530. [PMID: 31367335 DOI: 10.1039/c9tx00008a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 03/20/2019] [Indexed: 01/04/2023] Open
Abstract
Recent reports have concentrated on some androgens/antiandrogens and confirmed that certain chemicals have demonstrated androgenic/antiandrogenic activities in vitro. However, it is still unknown whether more chemicals in the human environment possess endocrine toxicity. 58A novel AR-mediated reporter gene assay based on LLC-MK2 cells was established by transiently co-transfecting with pARE-sv40-Luc, hAR-pcDNA3.1 and pRL-tk. pARE-sv40-Luc was constructed using a pGL3-promoter plasmid with three repeated androgen responsive elements. hAR-pcDNA3.1 was constructed using pcDNA3.1 with a hAR sequence. After transfection for 12 h, the culture medium was exposed to various concentrations of dihydrotestosterone (DHT) and other test chemicals (phthalic acid esters and dexamethasone) in order to measure the androgenic/antiandrogenic activity. The assay possessed a concentration-dependent response to DHT from 10-12 M to 10-6 M. Nilutamide concentrations of over 10-7 M completely blocked the luciferase expression induced by 10-9 M DHT. Other data showed that DBP, DEHP and MEHP possessed weak androgenic activity for certain concentration ranges, while DMP, DINP and DIBP did not show any androgenic activity. Moreover, five PAEs (DBP, DEHP, DINP, DIBP and MEHP) showed corresponding antiandrogenic activities for certain concentrations with an approximate tendency (MEHP > DBP > DEHP > DIBP > DINP). The assay is high-throughput, specific, and sensitive for the detection of androgenic/antiandrogenic chemicals. In addition, PAEs (especially transitional PAEs) exhibited corresponding androgenic/antiandrogenic activities for certain concentration ranges.
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Affiliation(s)
- Xiaoju Ma
- Department of Nutrition , School of Public Health , Chengdu University of T.C.M. , Chengdu , Sichuan , P.R. China 611137
| | - Jing Yang
- Department of Infectious Disease , Renmin Hospital , Hubei University of Medicine , Shiyan , Hubei , P.R. China 442000.,Department of Microbiology , School of Basic Medical Sciences , Hubei University of Medicine , Shiyan , Hubei , P.R. China 442000
| | - Hong Jia
- Department of Epidemiology and Statistics , School of Public Health , Southwest Medical University , Luzhou , Sichuan , P.R. China 646000
| | - Xiaohua Li
- Department of Emergency , Dongfeng Maojian Hospital , SINOPHARM Group Corporation , Shiyan , Hubei , P.R. China 442000
| | - Dawei Wang
- Department of Ultrasound , Taihe Hospital , Hubei University of Medicine , Shiyan , Hubei , P.R. China 442000
| | - Hongxia Fu
- Department of Clinical Laboratory Taihe Hospital , Hubei University of Medicine , Shiyan , Hubei , P.R. China 442000
| | - Jie Yuan
- Department of Microbiology , School of Basic Medical Sciences , Hubei University of Medicine , Shiyan , Hubei , P.R. China 442000
| | - Yun Li
- Department of Nutrition and Food Hygiene and Toxicology , West China School of Public Health , Sichuan University , Chengdu , Sichuan , P.R. China 610041 .
| | - Guangmei Zheng
- Department of Ultrasound , Renmin Hospital , Hubei University of Medicine , Shiyan , Hubei , P.R. China 442000 .
| | - Xiaoming Huang
- Department of Nutrition , Shenzhen Far-east Women and Children's Hospital , Shenzhen , Guangdong , P.R. China 518001.,Department of Nutrition and Food Hygiene and Toxicology , West China School of Public Health , Sichuan University , Chengdu , Sichuan , P.R. China 610041 .
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Conley JM, Lambright CS, Evans N, Strynar MJ, McCord J, McIntyre BS, Travlos GS, Cardon MC, Medlock-Kakaley E, Hartig PC, Wilson VS, Gray LE. Adverse Maternal, Fetal, and Postnatal Effects of Hexafluoropropylene Oxide Dimer Acid (GenX) from Oral Gestational Exposure in Sprague-Dawley Rats. ENVIRONMENTAL HEALTH PERSPECTIVES 2019; 127:37008. [PMID: 30920876 PMCID: PMC6768323 DOI: 10.1289/ehp4372] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 02/23/2019] [Accepted: 02/28/2019] [Indexed: 05/18/2023]
Abstract
BACKGROUND Hexafluoropropylene oxide dimer acid [(HFPO-DA), GenX] is a member of the per- and polyfluoroalkyl substances (PFAS) chemical class, and elevated levels of HFPO-DA have been detected in surface water, air, and treated drinking water in the United States and Europe. OBJECTIVES We aimed to characterize the potential maternal and postnatal toxicities of oral HFPO-DA in rats during sexual differentiation. Given that some PFAS activate peroxisome proliferator-activated receptors (PPARs), we sought to assess whether HFPO-DA affects androgen-dependent development or interferes with estrogen, androgen, or glucocorticoid receptor activity. METHODS Steroid receptor activity was assessed with a suite of in vitro transactivation assays, and Sprague-Dawley rats were used to assess maternal, fetal, and postnatal effects of HFPO-DA exposure. Dams were dosed daily via oral gavage during male reproductive development (gestation days 14-18). We evaluated fetal testes, maternal and fetal livers, maternal serum clinical chemistry, and reproductive development of F1 animals. RESULTS HFPO-DA exposure resulted in negligible in vitro receptor activity and did not impact testosterone production or expression of genes key to male reproductive development in the fetal testis; however, in vivo exposure during gestation resulted in higher maternal liver weights ([Formula: see text]), lower maternal serum thyroid hormone and lipid profiles ([Formula: see text]), and up-regulated gene expression related to PPAR signaling pathways in maternal and fetal livers ([Formula: see text]). Further, the pilot postnatal study indicated lower female body weight and lower weights of male reproductive tissues in F1 animals. CONCLUSIONS HFPO-DA exposure produced multiple effects that were similar to prior toxicity evaluations on PFAS, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but seen as the result of higher oral doses. The mean dam serum concentration from the lowest dose group was 4-fold greater than the maximum serum concentration detected in a worker in an HFPO-DA manufacturing facility. Research is needed to examine the mechanisms and downstream events linked to the adverse effects of PFAS as are mixture-based studies evaluating multiple PFAS. https://doi.org/10.1289/EHP4372.
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Affiliation(s)
- Justin M. Conley
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - Christy S. Lambright
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - Nicola Evans
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - Mark J. Strynar
- Exposure Methods and Measurements Division, National Exposure Research Laboratory, ORD, U.S. EPA, Research Triangle Park, North Carolina, USA
| | - James McCord
- Exposure Methods and Measurements Division, National Exposure Research Laboratory, ORD, U.S. EPA, Research Triangle Park, North Carolina, USA
| | - Barry S. McIntyre
- Toxicology Branch, Division of the National Toxicology Program (NTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Gregory S. Travlos
- Cellular and Molecular Pathology Branch, NTP, NIEHS, NIH, DHHS, Research Triangle Park, North Carolina, USA
| | - Mary C. Cardon
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - Elizabeth Medlock-Kakaley
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - Phillip C. Hartig
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - Vickie S. Wilson
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
| | - L. Earl Gray
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development (ORD), U.S. Environmental Protection Agency (U.S. EPA), Research Triangle Park, North Carolina, USA
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Conley JM, Lambright CS, Evans N, Cardon M, Furr J, Wilson VS, Gray LE. Mixed "Antiandrogenic" Chemicals at Low Individual Doses Produce Reproductive Tract Malformations in the Male Rat. Toxicol Sci 2018; 164:166-178. [PMID: 29945228 PMCID: PMC6677127 DOI: 10.1093/toxsci/kfy069] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Biomonitoring efforts have clearly shown that all humans are exposed to chemical mixtures. Of concern is whether or not exposure to mixtures during pregnancy contributes to congenital abnormalities in children even when each chemical is at an individual dose that does not affect the fetus. Here, we hypothesized that in utero exposure to a mixture of chemicals covering multiple "antiandrogenic" mechanisms of action at doses that individually have no adverse effect would result in permanent reproductive tract alterations in the male rat after birth. Pregnant dams were exposed to a range of dilutions (100%, 50%, 25%, 12.5%, 6.25%, or vehicle control) of a mixture containing pesticides, phthalates, and drugs (p, p'-DDE, linuron, prochloraz, procymidone, pyrifluquinazon, vinclozolin, finasteride, flutamide, simvastatin, and 9 phthalates [dipentyl, dicyclohexyl, di-2-ethylhexyl, dibutyl, benzyl butyl, diisobutyl, diisoheptyl, dihexyl, and diheptyl]). The top dose contained each chemical at 20% of its lowest observed adverse effect level (LOAEL) for the most sensitive male reproductive alteration following in utero exposure. We found that male rat offspring displayed a variety of neonatal, pubertal, and permanent adult effects across all dose levels. Even at the lowest dose (each chemical approximately 80-fold below lowest observed adverse effect level) there were permanent reductions in several reproductive tract tissue weights. In the top dose group, 100% of male offspring displayed permanent severe birth defects including genital malformations. Despite acting via 5 different molecular initiating events, a mixture of 18 chemicals can combine to produce additive effects even when each compound is at is at a relatively low dose.
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Affiliation(s)
- Justin M. Conley
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
| | - Christy S. Lambright
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
| | - Nicki Evans
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
| | - Mary Cardon
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
| | - Johnathan Furr
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
- Southern Research, Birmingham, AL 35205
| | - Vickie S. Wilson
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
| | - L. Earl Gray
- U.S. Environmental Protection Agency/Office of Research & Development/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division, Research Triangle Park, NC 27711
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Validation of an automated counting procedure for phthalate-induced testicular multinucleated germ cells. Toxicol Lett 2018; 290:55-61. [PMID: 29571896 DOI: 10.1016/j.toxlet.2018.03.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/06/2018] [Accepted: 03/18/2018] [Indexed: 12/12/2022]
Abstract
In utero exposure to certain phthalate esters results in testicular toxicity, characterized at the tissue level by induction of multinucleated germ cells (MNGs) in rat, mouse, and human fetal testis. Phthalate exposures also result in a decrease in testicular testosterone in rats. The anti-androgenic effects of phthalates have been more thoroughly quantified than testicular pathology due to the significant time requirement associated with manual counting of MNGs on histological sections. An automated counting method was developed in ImageJ to quantify MNGs in digital images of hematoxylin-stained rat fetal testis tissue sections. Timed pregnant Sprague Dawley rats were exposed by daily oral gavage from gestation day 17 to 21 with one of eight phthalate test compounds or corn oil vehicle. Both the manual counting method and the automated image analysis method identified di-n-butyl phthalate, butyl benzyl phthalate, dipentyl phthalate, and di-(2-ethylhexyl) phthalate as positive for induction of MNGs. Dimethyl phthalate, diethyl phthalate, the brominated phthalate di-(2-ethylhexyl) tetrabromophthalate, and dioctyl terephthalate were negative. The correlation between automated and manual scoring metrics was high (r = 0.923). Results of MNG analysis were consistent with these compounds' anti-androgenic activities, which were confirmed in an ex vivo testosterone production assay. In conclusion, we have developed a reliable image analysis method that can be used to facilitate dose-response studies for the reproducible induction of MNGs by in utero phthalate exposure.
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In utero combined di-(2-ethylhexyl) phthalate and diethyl phthalate exposure cumulatively impairs rat fetal Leydig cell development. Toxicology 2018; 395:23-33. [DOI: 10.1016/j.tox.2018.01.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 12/30/2017] [Accepted: 01/02/2018] [Indexed: 11/21/2022]
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Nepelska M, Odum J, Munn S. Adverse Outcome Pathway: Peroxisome Proliferator-Activated Receptor α Activation and Reproductive Toxicity—Development and Application in Assessment of Endocrine Disruptors/Reproductive Toxicants. ACTA ACUST UNITED AC 2017. [DOI: 10.1089/aivt.2017.0004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Małgorzata Nepelska
- European Commission, Joint Research Centre (JRC), Directorate F–Health, Consumers and Reference Materials, Chemical Safety and Alternative Methods, Ispra, Italy
| | - Jenny Odum
- Regulatory Science Associates, Kip Marina, Inverkip, Renfrewshire, England
| | - Sharon Munn
- European Commission, Joint Research Centre (JRC), Directorate F–Health, Consumers and Reference Materials, Chemical Safety and Alternative Methods, Ispra, Italy
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40
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Saillenfait AM, Sabaté JP, Denis F, Antoine G, Robert A, Roudot AC, Ndiaye D, Eljarrat E. Evaluation of the effects of α-cypermethrin on fetal rat testicular steroidogenesis. Reprod Toxicol 2017; 72:106-114. [DOI: 10.1016/j.reprotox.2017.06.133] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 05/15/2017] [Accepted: 06/21/2017] [Indexed: 10/19/2022]
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41
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Nassan FL, Coull BA, Gaskins AJ, Williams MA, Skakkebaek NE, Ford JB, Ye X, Calafat AM, Braun JM, Hauser R. Personal Care Product Use in Men and Urinary Concentrations of Select Phthalate Metabolites and Parabens: Results from the Environment And Reproductive Health (EARTH) Study. ENVIRONMENTAL HEALTH PERSPECTIVES 2017; 125:087012. [PMID: 28886595 PMCID: PMC5783668 DOI: 10.1289/ehp1374] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/05/2017] [Accepted: 04/06/2017] [Indexed: 05/22/2023]
Abstract
BACKGROUND Personal care products (PCPs) are exposure sources to phthalates and parabens; however, their contribution to men's exposure is understudied. OBJECTIVES We examined the association between PCP use and urinary concentrations of phthalate metabolites and parabens in men. METHODS In a prospective cohort, at multiple study visits, men self-reported their use of 14 PCPs and provided a urine sample (2004-2015, Boston, MA). We measured urinary concentrations of 9 phthalate metabolites and methylparaben, propylparaben, and butylparaben. We estimated the covariate-adjusted percent change in urinary concentrations associated with PCP use using linear mixed and Tobit mixed regressions. We also estimated weights for each PCP in a weighted binary score regression and modeled the resulting composite weighted PCP use. RESULTS Four hundred men contributed 1,037 urine samples (mean of 3/man). The largest percent increase in monoethyl phthalate (MEP) was associated with use of cologne/perfume (83%, p-value<0.01) and deodorant (74%, p-value<0.01). In contrast, the largest percent increase for parabens was associated with the use of suntan/sunblock lotion (66-156%) and hand/body lotion (79-147%). Increases in MEP and parabens were generally greater with PCP use within 6 h of urine collection. A subset of 10 PCPs that were used within 6 h of urine collection contributed to at least 70% of the weighted score and predicted a 254-1,333% increase in MEP and parabens concentrations. Associations between PCP use and concentrations of the other phthalate metabolites were not statistically significant. CONCLUSIONS We identified 10 PCPs of relevance and demonstrated that their use within 6 h of urine collection strongly predicted MEP and paraben urinary concentrations. https://doi.org/10.1289/EHP1374.
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Affiliation(s)
- Feiby L Nassan
- Department of Environmental Health, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
| | - Brent A Coull
- Department of Biostatistics, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
| | - Audrey J Gaskins
- Department of Nutrition, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
- Channing Division of Network Medicine, Brigham and Women's Hospital & Harvard Medical School , Boston, Massachusetts, USA
| | - Michelle A Williams
- Department of Epidemiology, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
| | - Niels E Skakkebaek
- Department of Growth and Reproduction & EDMaRC, Rigshospitalet University of Copenhagen , Copenhagen, Denmark
| | - Jennifer B Ford
- Department of Environmental Health, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
| | - Xiaoyun Ye
- National Center for Environmental Health, Centers for Disease Control and Prevention , Atlanta, Georgia, USA
| | - Antonia M Calafat
- National Center for Environmental Health, Centers for Disease Control and Prevention , Atlanta, Georgia, USA
| | - Joseph M Braun
- Department of Epidemiology, School of Public Health, Brown University , Providence, Rhode Island, USA
| | - Russ Hauser
- Department of Environmental Health, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health , Boston, Massachusetts, USA
- Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School , Boston, Massachusetts, USA
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42
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Mono-(2-ethylhexyl) phthalate-induced Sertoli cell injury stimulates the production of pro-inflammatory cytokines in Fischer 344 rats. Reprod Toxicol 2017; 69:150-158. [PMID: 28238932 DOI: 10.1016/j.reprotox.2017.02.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 02/06/2017] [Accepted: 02/21/2017] [Indexed: 11/22/2022]
Abstract
Exposure of rodents to the Sertoli cell (SC) toxicant mono-(2-ethylhexyl) phthalate (MEHP) has been reported to trigger an infiltration of macrophages into the testis in an age- and species-dependent manner. Here we challenge the hypothesis that the peripubertal rat-specific infiltration of macrophages after MEHP exposure is due, in part, to an increase in SC-specific inflammatory cytokine expression. To rule out that germ cell(GC) apoptosis itself is responsible for macrophage recruitment, rats were exposed to a direct GC toxicant, methoxyacetic acid (MAA), but no infiltration of macrophages was observed. Next, mRNA levels of inflammatory cytokines were evaluated after MEHP exposure. IL-1α, IL-6, and MCP-1 expression were increased in vivo and correlated with macrophage infiltration in a species-specific manner. Additionally, IL-6 and MCP-1 expression was increased in SC-GC co-cultures and ASC-17D SCs. These results indicate that MEHP-injury in pubertal rats specifically stimulates secretion of pro-inflammatory cytokines and alters the immune microenvironment.
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43
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Gao HT, Xu R, Cao WX, Qian LL, Wang M, Lu L, Xu Q, Yu SQ. Effects of six priority controlled phthalate esters with long-term low-dose integrated exposure on male reproductive toxicity in rats. Food Chem Toxicol 2017; 101:94-104. [PMID: 28089693 DOI: 10.1016/j.fct.2017.01.011] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 01/10/2017] [Accepted: 01/12/2017] [Indexed: 01/16/2023]
Abstract
Human beings are inevitably exposed to ubiquitous phthalate esters (PEs) surroundings. The purposes of this study were to investigate the effects of long-term low-dose exposure to the mixture of six priority controlled phthalate esters (MIXPs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DBP), butyl benzyl phthalate (BBP), di(2-ethyhexyl) phthalate (DEHP) and di-n-octyl phthalate (DNOP), on male rat reproductive system and further to explore the underlying mechanisms of the reproductive toxicity. The male rats were orally exposed to either sodium carboxymethyl cellulose as controls or MIXPs at three different low-doses by gavage for 15 weeks. Testosterone and luteinizing hormone (LH) in serum were analyzed, and pathological examinations were performed for toxicity evaluation. Steroidogenic proteins (StAR, P450scc, CYP17A1 and 17β-HSD), cell cycle and apoptosis-related proteins (p53, Chk1, Cdc2, CDK6, Bcl-2 and Bax) were measured for mechanisms exploration. MIXPs with long-term low-dose exposure could cause male reproductive toxicity to the rats, including the decrease of both serum and testicular testosterone, and the constructional damage of testis. These effects were related to down-regulated steroidogenic proteins, arresting cell cycle progression and promoting apoptosis in rat testicular cells. The results indicate that MIXPs with long-term low-dose exposure may pose male reproductive toxicity in human.
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Affiliation(s)
- Hai-Tao Gao
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Run Xu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Wei-Xin Cao
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Liang-Liang Qian
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Min Wang
- Zibo Municipal Center for Disease Control and Prevention, Zibo 255026, China
| | - Lingeng Lu
- Department of Chronic Disease Epidemiology, Yale School of Public Health, School of Medicine, Yale University, New Haven, CT 06520-8034, USA
| | - Qian Xu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China; Department of Chronic Disease Epidemiology, Yale School of Public Health, School of Medicine, Yale University, New Haven, CT 06520-8034, USA.
| | - Shu-Qin Yu
- Jiangsu Key Laboratory for Supramolecular Medicinal Material and Applications, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China; Jiangsu Province Key Laboratory for Molecular and Medicinal Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China.
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44
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Sohn J, Kim S, Koschorreck J, Kho Y, Choi K. Alteration of sex hormone levels and steroidogenic pathway by several low molecular weight phthalates and their metabolites in male zebrafish (Danio rerio) and/or human adrenal cell (H295R) line. JOURNAL OF HAZARDOUS MATERIALS 2016; 320:45-54. [PMID: 27513369 DOI: 10.1016/j.jhazmat.2016.08.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/09/2016] [Accepted: 08/03/2016] [Indexed: 05/05/2023]
Abstract
Low molecular weight phthalates, such as diethyl phthalate (DEP), benzyl butyl phthalate (BBzP), or diisobutyl phthalate (DiBP), are suspected to disrupt endocrine system. However, their adverse effects on sex steroid hormones and underlying mechanisms are not well-documented. The aim of this study is to investigate the effects of major low molecular weight phthalates (LMWPs), i.e., DEP, BBzP, and DiBP, and their hydrolytic metabolites, on sex steroid hormone system, employing male zebrafish and/or a human adrenocortical carcinoma (H295R) cell. In male zebrafish, 14-day exposure to DEP, BBzP, or DiBP significantly decreased testosterone (T) concentrations. All test compounds significantly up-regulated cyp19a gene expression, and down-regulated star and 3β hsd genes in the male fish. In H295R cell, all test compounds except monoisobutyl phthalate (MiBP) reduced T concentrations and increased E2/T ratio. Gene expression changes in H295R cell, e.g., significant down-regulation of StAR gene and up-regulation of CYP19A gene, supported depressed synthesis of sex hormones in the adrenal cell. Our results show that not only DEP, BBzP, and DiBP, but also their hydrolytic metabolites disrupt sex hormone balances through modulating key steroidogenic genes in the human adrenal cells and in zebrafish.
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Affiliation(s)
- Juhae Sohn
- Department of Environmental Health Sciences, School of Public Heath, Seoul National University, Seoul 08826, Republic of Korea
| | - Sujin Kim
- Department of Environmental Health Sciences, School of Public Heath, Seoul National University, Seoul 08826, Republic of Korea
| | - Jan Koschorreck
- Federal Environment Agency (Umweltbundesamt), 06813 Dessau-Rosslau, Germany
| | - Younglim Kho
- Department of Health, Environment and Safety, Eulji University, Seongnam 13135, Republic of Korea
| | - Kyungho Choi
- Department of Environmental Health Sciences, School of Public Heath, Seoul National University, Seoul 08826, Republic of Korea.
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45
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Howdeshell KL, Hotchkiss AK, Gray LE. Cumulative effects of antiandrogenic chemical mixtures and their relevance to human health risk assessment. Int J Hyg Environ Health 2016; 220:179-188. [PMID: 27923611 DOI: 10.1016/j.ijheh.2016.11.007] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 10/21/2016] [Accepted: 11/14/2016] [Indexed: 11/28/2022]
Abstract
Toxicological studies of defined chemical mixtures assist human health risk assessment by establishing how chemicals interact with one another to induce an effect. This paper reviews how antiandrogenic chemical mixtures can alter reproductive tract development in rats with a focus on the reproductive toxicant phthalates. The reviewed studies compare observed mixture data to mathematical mixture model predictions based on dose addition or response addition to determine how the individual chemicals in a mixture interact (e.g., additive, greater, or less than additive). Phthalate mixtures were observed to act in a dose additive manner based on the relative potency of the individual phthalates to suppress fetal testosterone production. Similar dose additive effects have been reported for mixtures of phthalates with antiandrogenic pesticides of differing mechanisms of action. Overall, data from these phthalate experiments in rats can be used in conjunction with human biomonitoring data to determine individual hazard indices, and recent cumulative risk assessments in humans indicate an excess risk to antiandrogenic chemical mixtures that include phthalates only or phthalates in combination with other antiandrogenic chemicals.
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Affiliation(s)
- Kembra L Howdeshell
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences (NIEHS), PO Box 12233, Mail Drop K2-04, Research Triangle Park, NC 27709-2233, USA.
| | - Andrew K Hotchkiss
- National Center for Environmental Assessment (NCEA), National Health and Environmental Effects Research Laboratories (NHEERL), Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | - L Earl Gray
- Toxicology Assessment Division, National Health and Environmental Effects Research Laboratories (NHEERL), Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, NC 27711, USA
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46
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Zhu Y, Xu H, Li M, Gao Z, Huang J, Liu L, Huang X, Li Y. Daidzein impairs Leydig cell testosterone production and Sertoli cell function in neonatal mouse testes: An in vitro study. Mol Med Rep 2016; 14:5325-5333. [PMID: 27840926 DOI: 10.3892/mmr.2016.5896] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 09/26/2016] [Indexed: 11/06/2022] Open
Abstract
Isoflavone is a type of phytoestrogen that exists in soy‑based products. Previous studies have reported that certain foods containing isoflavones, particularly infant formula, may have potential adverse effects on male reproductive function. However, few studies have focused on the effects of isoflavones on testosterone biosynthesis and Sertoli cell function during the neonatal period. The aim of the present study was to investigate the influence of daidzein, a common isoflavone, on testosterone secretion and Sertoli cell function during the neonatal period. The organ culture method was used to assess the effects of daidzein on neonatal mouse testes. Cultured testes were treated with daidzein (0, 0.03, 0.3, 3 or 30 µmol/l) for 72 h. To verify the mechanism of action of daidzein on androgen production, Leydig cells were also treated with daidzein for 24 h. As anticipated, testosterone secretions were suppressed by daidzein (30 µmol/l) in cultured testes and Leydig cells. Further analysis demonstrated that the expression levels of steroidogenic acute regulatory protein (StAR), cholesterol side‑chain cleavage enzyme (P450scc) and 3β‑hydroxysteroid dehydrogenase (3β‑HSD), which are transport proteins and key enzymes in androgen biosynthesis, were suppressed in cultured neonatal mouse testes. In addition, the expression levels of StAR, P450scc, 3β‑HSD and 17α‑hydroxylase/20‑lyase were decreased in Leydig cells. Notably, proliferation of Sertoli cells was also inhibited by daidzein (30 µmol/l). Furthermore, the expression levels of vimentin were significantly suppressed in the testes following treatment with daidzein, whereas inhibin B expression exhibited no change. In conclusion, daidzein may suppress steroidogenic capability and impair Sertoli cell function in the neonatal period in vitro.
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Affiliation(s)
- Yanfeng Zhu
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Hua Xu
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Min Li
- Department of Public Health, Luzhou Medical College, Luzhou, Sichuan 646000, P.R. China
| | - Zhibin Gao
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Jie Huang
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Linxi Liu
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Xiaoming Huang
- Department of Public Health, Luzhou Medical College, Luzhou, Sichuan 646000, P.R. China
| | - Yun Li
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan 610041, P.R. China
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47
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Varshavsky JR, Zota AR, Woodruff TJ. A Novel Method for Calculating Potency-Weighted Cumulative Phthalates Exposure with Implications for Identifying Racial/Ethnic Disparities among U.S. Reproductive-Aged Women in NHANES 2001-2012. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:10616-10624. [PMID: 27579903 PMCID: PMC5748889 DOI: 10.1021/acs.est.6b00522] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Phthalates are ubiquitous chemicals linked to hormonal disruptions that affect reproduction and development. Multiple antiandrogenic phthalates exposure during fetal development can have greater impacts than individual exposure; thus, the National Academy of Sciences (NAS) recommends them for cumulative assessment. Using National Health and Nutrition Examination Survey data (NHANES, 2001-2012), we developed a potency-weighted sum of daily intake (∑androgen-disruptor; μg/kg/day) of di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), butyl benzyl phthalate (BBzP), and di(2-ethylhexyl) phthalate (DEHP) based on NAS recommendations, and included diethyl phthalate (DEP) and diisononyl phthalate (DiNP) in additional metrics (2005-2012). We compared racial/ethnic differences in ∑androgen-disruptor among 2842 reproductive-aged women. In sensitivity analyses, we assessed the influence of potency assumptions, alternate urine dilution adjustment methods, and weighting phthalate metabolites directly rather than daily intake estimates of parent compounds. We found that DEHP contributed most to ∑androgen-disruptor (48-64%), and that ∑androgen-disruptor decreased over time. Black women generally had higher cumulative exposures than white women, although the magnitude and precision of the difference varied by model specification. Our approach provides a blueprint for combining chemical exposures linked to common adverse outcomes, and should be considered in future exposure, risk, and epidemiological studies.
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Affiliation(s)
- Julia R. Varshavsky
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California 94720, United States
| | - Ami R. Zota
- Department of Environmental and Occupational Health, Milken Institute School of Public Health, George Washington University, Washington, D.C. 20052, United States
| | - Tracey J. Woodruff
- Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, Institute for Health Policy Studies, University of California, San Francisco, San Francisco, California 94143, United States
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48
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Zhang J, Jin S, Zhao J, Li H. Effect of dibutyl phthalate on expression of connexin 43 and testosterone production of leydig cells in adult rats. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2016; 47:131-135. [PMID: 27676332 DOI: 10.1016/j.etap.2016.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 08/31/2016] [Accepted: 09/14/2016] [Indexed: 06/06/2023]
Abstract
To investigate the adverse effect of dibutyl phthalate (DBP) on Leydig cells and its mechanism related to gap junction, Leydig cells isolated from adult rats were treated with 0.1% dimethylsulfoxide (DMSO), 50mg/L DBP, 50mg/L DBP+10μM prostaglandin E2 (PGE2) and 40μM flutamide respectively. Radioimmunoassay, semi-quantitative RT-PCR, immunofluorescence and Western blot were applied to determine the expression of testosterone and Connexin 43 (Cx43) in Leydig cells. The expression of testosterone and Cx43 were both decreased in DBP group (P<0.05). While Cx43 was up-regulated after administered to PGE2, there was no significant change in testosterone. However, testosterone was down-regulated with a significant decrease of Cx43 in flutamide group. The results indicated that the inhibitory effect of DBP on testosterone production was not through the down-regulation of Cx43. On the contrary, the change of testosterone can influence the expression of Cx43 in Leydig cells.
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Affiliation(s)
- Jing Zhang
- Department of Environmental Hygiene, School of Public Health, Beihua University, Jilin 132013, China
| | - Shuguang Jin
- Department of Environmental Hygiene, School of Public Health, Beihua University, Jilin 132013, China
| | - Jinchang Zhao
- Department of Environmental Hygiene, School of Public Health, Beihua University, Jilin 132013, China
| | - Huan Li
- Department of Environmental Hygiene, School of Public Health, Beihua University, Jilin 132013, China.
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49
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Ahmad S, Khan MF, Parvez S, Akhtar M, Raisuddin S. Molecular docking reveals the potential of phthalate esters to inhibit the enzymes of the glucocorticoid biosynthesis pathway. J Appl Toxicol 2016; 37:265-277. [DOI: 10.1002/jat.3355] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/08/2016] [Accepted: 05/10/2016] [Indexed: 02/06/2023]
Affiliation(s)
- Shahzad Ahmad
- Department of Medical Elementology and Toxicology; Jamia Hamdard (Hamdard University); New Delhi 110062 India
| | - Mohemmed Faraz Khan
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy; Jamia Hamdard (Hamdard University); New Delhi 110062 India
| | - Suhel Parvez
- Department of Medical Elementology and Toxicology; Jamia Hamdard (Hamdard University); New Delhi 110062 India
| | - Mohammad Akhtar
- Department of Pharmacology, Faculty of Pharmacy; Jamia Hamdard (Hamdard University); New Delhi 110062 India
| | - Sheikh Raisuddin
- Department of Medical Elementology and Toxicology; Jamia Hamdard (Hamdard University); New Delhi 110062 India
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50
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Akinjo OO, Gant TW, Marczylo EL. Perturbation of epigenetic processes by doxorubicin in the mouse testis. Toxicol Res (Camb) 2016; 5:1229-1243. [PMID: 30090428 DOI: 10.1039/c6tx00078a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/30/2016] [Indexed: 12/19/2022] Open
Abstract
Epigenetic processes play a major role in normal mammalian development, particularly during gametogenesis and early embryogenesis. Thus, perturbation of epigenetic processes in the testis by xenobiotics could have a major impact on testicular function and fertility, and potentially affect the development and health of subsequent generations. There has been substantial research into the epigenetic toxicity of environmental exposures over the last decade. However, few studies have focussed on pharmaceutical drugs, which due to the nature of their use are typically found at much higher concentrations within exposed individuals than environmental chemicals. Here, we investigated genome-wide changes in testicular mRNA transcription, microRNA expression and DNA methylation to assess the contribution of epigenetic mechanisms to the testicular toxicity induced by doxorubicin (DOX) as a representative, widely used and well-characterised anti-cancer drug. We demonstrated that DOX is able to induce transcriptional, microRNA and DNA methylation changes, which perturb pathways involved in stress/cell death and survival and testicular function and lead to germ cell loss and reproductive organ damage. This identified potential novel mechanisms of DOX-induced testicular toxicity for further focussed investigations. Such work is required to fully assess the role of epigenetics in toxicity, determine whether single and/or multigenerational epigenetic toxicity is a real public health concern, and begin to develop and incorporate relevant epigenetic endpoints into regulatory toxicology.
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Affiliation(s)
- Oluwajoba O Akinjo
- Toxicology Department , CRCE , PHE , Chilton , Oxfordshire OX11 0RQ , UK .
| | - Timothy W Gant
- Toxicology Department , CRCE , PHE , Chilton , Oxfordshire OX11 0RQ , UK .
| | - Emma L Marczylo
- Toxicology Department , CRCE , PHE , Chilton , Oxfordshire OX11 0RQ , UK .
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