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Liu T, Lin H, Zhang L. Arsenic bioaccumulation and biotransformation in the marine copepod Tigriopus japonicus under chronic dietborne and waterborne exposure. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134655. [PMID: 38805822 DOI: 10.1016/j.jhazmat.2024.134655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 05/09/2024] [Accepted: 05/17/2024] [Indexed: 05/30/2024]
Abstract
Arsenic (As) can be transferred along the food chain, while little is known about the toxic effects of dietborne As on marine copepods. In this study, we investigated the short-term and long-term effects of waterborne and dietborne As exposure on the bioaccumulation and biotransformation, as well as developmental toxicity of Tigriopus japonicus. Under acute As exposure, As bioaccumulation increased and reached a plateau with increasing exposure concentration. Moreover, As accumulation at dietborne exposure was 4.3 and 5.7 times greater than that at control group for AsIII and AsV, respectively. At chronic As exposure, As accumulation increased continuously with exposure time, with a 2.8-day extension of development time and a 45% reduction in 10-d fecundity under dietborne exposure compared to control, whereas 2.3-day extension of development time and a 20% reduction in 10-d fecundity were observed under waterborne exposure. Among As species, inorganic As had the highest concentrations, but the proportion of inorganic As decreased from 89% to 63% during 4 to 21 d of exposure, suggesting the conversion of inorganic As to organic As. The organic As was dominated by arsenobetaine (AsB, 13-25%), followed by monomethylarsenic (MMA, 8-25%). These results suggest that dietborne exposure has more pronounced toxic effects on T. japonicus, but the toxicity of As could be reduced through biotransformation under chronic exposure. Therefore, the arsenic species should be considered when assessing As toxicity.
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Affiliation(s)
- Tianrui Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haoye Lin
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Li Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Sanya Institute of Ocean Eco-Environmental Engineering, Sanya 572025, China.
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Pollack AZ, Marroquin JM. Invited Perspective: Metals and Menarche. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:21301. [PMID: 36729393 PMCID: PMC9894152 DOI: 10.1289/ehp12555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Affiliation(s)
- Anna Z. Pollack
- Department of Global and Community Health, College of Public Health, George Mason University, Fairfax, Virginia, USA
| | - Joanna M. Marroquin
- Department of Global and Community Health, College of Public Health, George Mason University, Fairfax, Virginia, USA
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Malin Igra A, Rahman A, Johansson AL, Pervin J, Svefors P, Arifeen SE, Vahter M, Persson LÅ, Kippler M. Early Life Environmental Exposure to Cadmium, Lead, and Arsenic and Age at Menarche: A Longitudinal Mother-Child Cohort Study in Bangladesh. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:27003. [PMID: 36729392 PMCID: PMC9894154 DOI: 10.1289/ehp11121] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 12/07/2022] [Accepted: 01/03/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Several metals act as endocrine disruptors, but there are few large longitudinal studies about associations with puberty onset. OBJECTIVES We evaluated whether early life cadmium, lead, and arsenic exposure was associated with timing of menarche. METHODS In a mother-child cohort in rural Bangladesh (n=935), the exposure was assessed by concentrations in maternal erythrocytes in early pregnancy and in girls' urine at 5 and 10 years of age using inductively coupled plasma mass spectrometry. The girls were interviewed twice, at average ages 13.3 [standard deviation (SD)=0.43] and 13.8 (SD=0.43) y, and the date of menarche, if present, was recorded. Associations were assessed using Kaplan-Meier analysis and multivariable-adjusted Cox regression. RESULTS In total, 77% of the girls (n=717) had reached menarche by the second follow-up. The median age of menarche among all girls was 13.0 y (25th-75th percentiles: 12.4-13.7 y). At 10 years of age, median urinary cadmium was 0.25μg/L (5th-95th percentiles: 0.087-0.72μg/L), lead 1.6μg/L (0.70-4.2μg/L), and arsenic 54μg/L (19-395μg/L). Given the same age, girls in the highest quartile of urinary cadmium at 5 and 10 years of age had a lower rate of menarche than girls in the lowest quartile, with an adjusted hazard ratio of (HR) 0.80 (95% CI: 0.62, 1.01) at 5 years of age, and 0.77 (95% CI: 0.60, 0.98) at 10 years of age. This implies that girls in the highest cadmium exposure quartile during childhood had a higher age at menarche. Comparing girls in the highest to the lowest quartile of urinary lead at 10 years of age, the former had a higher rate of menarche [adjusted HR = 1.23 (95% CI: 0.97, 1.56)], implying lower age at menarche, whereas there was no association with urinary lead at 5 years of age. Girls born to mothers in the highest quartile of erythrocyte arsenic during pregnancy were less likely to have attained menarche than girls born to mothers in the lowest quartile [adjusted HR= 0.79 (95% CI: 0.62, 0.99)]. No association was found with girls' urinary arsenic exposure. DISCUSSION Long-term childhood cadmium exposure was associated with later menarche, whereas the associations with child lead exposure were inconclusive. Maternal exposure to arsenic, but not cadmium or lead, was associated with later menarche. https://doi.org/10.1289/EHP11121.
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Affiliation(s)
| | - Anisur Rahman
- Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Anna L.V. Johansson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Jesmin Pervin
- Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Pernilla Svefors
- Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden
| | - Shams El Arifeen
- Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Marie Vahter
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Lars-Åke Persson
- Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden
- London School of Hygiene and Tropical Medicine, London, UK
| | - Maria Kippler
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
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Yao Z, Lin M, Lin T, Gong X, Qin P, Li H, Kang T, Ye J, Zhu Y, Hong Q, Liu Y, Li Y, Wang J, Fang F. The expression of IGFBP-5 in the reproductive axis and effect on the onset of puberty in female rats. Reprod Biol Endocrinol 2022; 20:100. [PMID: 35821045 PMCID: PMC9277959 DOI: 10.1186/s12958-022-00966-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 06/18/2022] [Indexed: 11/21/2022] Open
Abstract
Insulin-like growth factor-binding protein-5 (IGFBP-5) has recently been shown to alter the reproductive capacity by regulating insulin-like growth factor (IGF) bioavailability or IGF-independent effects. The present study aimed to investigate the effect and mechanism of IGFBP-5 on the onset of puberty in female rats. Immunofluorescence and real-time quantitative PCR were used to determine the expression and location of IGFBP-5 mRNA and protein distribution in the infant's hypothalamus-pituitary-ovary (HPO) axis prepuberty, peripuberty, puberty and adult female rats. Prepubertal rats with IGFBP-5 intracerebroventricular (ICV) were injected to determine the puberty-related genes expression and the concentrations of reproductive hormones. Primary hypothalamic cells were treated with IGFBP-5 to determine the expression of puberty-related genes and the Akt and mTOR proteins. Results showed that Igfbp-5 mRNA and protein were present on the HPO axis. The addition of IGFBP-5 to primary hypothalamic cells inhibited the expression of Gnrh and Igf-1 mRNAs (P < 0.05) and increased the expression of AKT and mTOR protein (P < 0.01). IGFBP-5 ICV-injection delayed the onset of puberty, reduced Gnrh, Igf-1, and Fshβ mRNAs, and decreased the concentrations of E2, P4, FSH,serum LH levels and the ovaries weight (P < 0.05). More corpus luteum and fewer primary follicles were found after IGFBP-5 injection (P < 0.05).
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Affiliation(s)
- Zhiqiu Yao
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Maosen Lin
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Tao Lin
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Xinbao Gong
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Pin Qin
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Hailing Li
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Tiezhu Kang
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Jing Ye
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Yanyun Zhu
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Qiwen Hong
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Ya Liu
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Yunsheng Li
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Juhua Wang
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China
| | - Fugui Fang
- Anhui Provincial Key Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, 130 Changjiang West Road, Hefei, 230036, Anhui, China.
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, Anhui, China.
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Rahman A, Kippler M, Pervin J, Tarafder C, Lucy IJ, Svefors P, Arifeen SE, Persson LÅ. A cohort study of the association between prenatal arsenic exposure and age at menarche in a rural area, Bangladesh. ENVIRONMENT INTERNATIONAL 2021; 154:106562. [PMID: 33866057 DOI: 10.1016/j.envint.2021.106562] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/23/2021] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Millions of individuals worldwide, particularly in Bangladesh, are exposed to arsenic, mainly through drinking water from tube wells. Arsenic is a reproductive toxicant, but there is limited knowledge of whether it influences pubertal development. OBJECTIVES We evaluated the association between prenatal arsenic exposure and age at menarche. METHODS This prospective study was based on data from two studies conducted in Matlab, Bangladesh-the Maternal and Infant Nutrition Interventions in Matlab (MINIMat) trial and the Health Consequences of Arsenic in Matlab (AsMat) study. We included 809 MINIMat girls who participated in assessing age at menarche from July 2016 to June 2017 and had prenatal arsenic exposure data through the AsMat study via measurements in tube well water used by the mothers during pregnancy. The exposure was categorized into <10, 10-49, 50-99, 100-199, and ≥200 µg/L. We used Kaplan-Meier and Cox proportional hazards analyses with adjustment for potential confounders to evaluate the association between arsenic exposure and age at menarche. The results were presented by adjusted hazards ratio (aHR) with a 95% confidence interval (CI). RESULTS The median arsenic concentration in tube well water consumed by pregnant women was 80 µg/L (interquartile range 2-262 µg/L), and 55% drank water with concentrations above Bangladesh's acceptable value of 50 µg/L. The median age at menarche was 13.0 years. The unadjusted analysis revealed 3.2 months delay in menarche for girls exposed to arsenic concentrations ≥200 µg/L compared with the girl exposed to arsenic concentrations <10 µg/L. Girls exposed to the same higher arsenic concentrations were 23% (aHR 0.77, 95% CI: 0.63-0.95) less likely to have reached menarche than girls exposed to low arsenic concentrations. CONCLUSIONS Increased levels of prenatal arsenic exposure were associated with older age at menarche. This delay may indicate endocrine disruptions that could potentially result in adverse health consequences in later life. This finding, along with other severe adverse health reinforces the need for arsenic mitigation at the population level.
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Affiliation(s)
- Anisur Rahman
- Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Bangladesh; Women's and Children's Health, Uppsala University, Uppsala, Sweden.
| | - Maria Kippler
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Jesmin Pervin
- Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Bangladesh
| | - Chandan Tarafder
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh
| | - Ishrat Javeen Lucy
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh
| | - Pernilla Svefors
- Women's and Children's Health, Uppsala University, Uppsala, Sweden
| | - Shams El Arifeen
- Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Bangladesh
| | - Lars Åke Persson
- Women's and Children's Health, Uppsala University, Uppsala, Sweden; London School of Hygiene & Tropical Medicine, London, UK
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Ommati MM, Shi X, Li H, Zamiri MJ, Farshad O, Jamshidzadeh A, Heidari R, Ghaffari H, Zaker L, Sabouri S, Chen Y. The mechanisms of arsenic-induced ovotoxicity, ultrastructural alterations, and autophagic related paths: An enduring developmental study in folliculogenesis of mice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 204:110973. [PMID: 32781346 DOI: 10.1016/j.ecoenv.2020.110973] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/28/2020] [Accepted: 06/29/2020] [Indexed: 05/18/2023]
Abstract
Arsenic (As) exerts a wide range of adverse effects on biological systems, including the reproductive organs in males and females. However, the mechanisms of As-induced reproductive toxicity are mostly obscure. Recently, we showed that autophagy is an essential route for As2O3-induced reprotoxicity through the hypothalamic-pituitary-gonadal-sperm (HPG-S) axis in pubertal and matured F1-male mice. However, the role of autophagy in As2O3- induced ovarian toxicity is mostly unknown. Hence, this study aimed to elucidate the role of oxidative stress, mitochondrial impairment, and autophagic processes in the ovary of As-exposed female mice. For this purpose, mature female mice were challenged with 0, low (0.2), medium (2), and high (20 ppm) As2O3 from 35-days before mating till weaning their pups, and the F1- females from weaning until maturity. Then, all the mice were sacrificed, and oxidative stress parameters, mitochondrial indices, electron microscopic evaluation of the ovaries, expression of autophagic-related genes and proteins, and autophagosome formation were assessed. It was shown that medium and high As2O3 doses were a potent inducer of oxidative stress, mitochondrial dysfunction, and autophagy in the ovary of F1-generation. A dose-dependent increment in the gene expression of PDK1, PI3K, TSC2, AMPK, ULK1, ATG13, Beclin1, ATG12, ATG5, LC3, P62, ATG3, ATG7, and p62, as well as protein expression of Beclin1, and LC3- I, II, was evident in the ovaries of the As-treated animals. Moreover, a dose-dependent decrease in the expression of mTOR and Bcl-2 genes, and mTOR protein was detected with increasing doses of As, suggesting that As treatment-induced autophagy. Along with a dose-dependent increase in the number of MDC-labeled autophagic vacuoles, transmission electron microscopy also confirmed more autophagosomes and injured mitochondria in medium and high As2O3 doses groups. As2O3 also negatively affected the mean body weight, litter size, organ coefficient, and stereological indices in female mice. Finally, in physiological conditions, arsenic trioxide (As2O3) leads to an increased level of autophagy in the oocyte when many oocytes were being lost. These findings indicated that an imbalance in the oxidant-antioxidant system, mitochondrial impairment, and the autophagic process, through inhibition of mTOR, dependent and independent pathways, and Bcl-2, as well as activation of AMPK/PI3K/Beclin1/LC3 routes, could play a pivotal role in As-induced reproductive toxicity through ovarian dysfunction in females.
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Affiliation(s)
- Mohammad Mehdi Ommati
- Department of Bioinformatics, College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi, 030801, PR China.
| | - Xiong Shi
- Department of Bioinformatics, College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi, 030801, PR China
| | - Huifeng Li
- Department of Bioinformatics, College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi, 030801, PR China
| | | | - Omid Farshad
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, 158371345, Shiraz, Iran
| | - Akram Jamshidzadeh
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, 158371345, Shiraz, Iran
| | - Reza Heidari
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, 158371345, Shiraz, Iran.
| | - Hasti Ghaffari
- Department of Veterinary Sciences, Islamic Azad University Urmia Branch, Urmia, Iran
| | - Ladan Zaker
- Department of Hematology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Samira Sabouri
- Department of Bioinformatics, College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi, 030801, PR China
| | - Yuanyu Chen
- Department of Bioinformatics, College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi, 030801, PR China
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Wang L, Yan R, Yang Q, Li H, Zhang J, Shimoda Y, Kato K, Yamanaka K, An Y. Role of GH/IGF axis in arsenite-induced developmental toxicity in zebrafish embryos. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 201:110820. [PMID: 32531574 DOI: 10.1016/j.ecoenv.2020.110820] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/09/2020] [Accepted: 05/26/2020] [Indexed: 05/25/2023]
Abstract
Growth hormone (GH)/insulin-like growth factor (IGF) axis plays a critical role in fetal development. However, the effect of arsenite exposure on the GH/IGF axis and its toxic mechanism are still unclear. Zebrafish embryos were exposed to a range of NaAsO2 concentrations (0.0-10.0 mM) between 4 and 120 h post-fertilization (hpf). Development indexes of survival, malformation, hatching rate, heart rate, body length and locomotor behavior were measured. Hormone levels, GH/IGF axis-related genes, and nerve-related genes were also tested. The results showed that survival rate, hatching rate, heart rate, body length and locomotor behavior all decreased, while deformity increased. At 120 hpf, the survival rate of zebrafish in 1.5 mM NaAsO2 group was about 70%, the deformity rate exceeded 20%, and the body length shortened to 3.35 mm, the movement distance of zebrafish decreased approximately 63.6% under light condition and about 52.4% under dark condition. The level of GH increased and those of IGF did not change significantly, while the expression of GH/IGF axis related genes (ghra, ghrb, igf2r, igfbp3, igfbp2a, igfbp5b) and nerve related genes (dlx2, shha, ngn1, elavl3, gfap) decreased. In 1.5 mM NaAsO2 group, the decrease of igfbp3 and igfbp5b was almost obvious, about 78.2% and 72.2%. The expression of nerve genes in 1.5 mM NaAsO2 group all have declined by more than 50%. These findings suggested that arsenite exerted disruptive effects on the endocrine system by interfering with the GH/IGF axis, leading to zebrafish embryonic developmental toxicity.
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Affiliation(s)
- Luna Wang
- Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, 215123, Jiangsu, China
| | - Rui Yan
- Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, 215123, Jiangsu, China
| | - Qianlei Yang
- Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, 215123, Jiangsu, China
| | - Heran Li
- Microwants International LTD, Hong Kong, China
| | - Jie Zhang
- Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, 215123, Jiangsu, China
| | - Yasuyo Shimoda
- Laboratory of Environmental Toxicology and Carcinogenesis, School of Pharmacy, Nihon University, Chiba, 274-8555, Japan
| | - Koichi Kato
- Laboratory of Environmental Toxicology and Carcinogenesis, School of Pharmacy, Nihon University, Chiba, 274-8555, Japan
| | - Kenzo Yamanaka
- Laboratory of Environmental Toxicology and Carcinogenesis, School of Pharmacy, Nihon University, Chiba, 274-8555, Japan.
| | - Yan An
- Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, 215123, Jiangsu, China.
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Endocrine Disruptors Induced Distinct Expression of Thyroid and Estrogen Receptors in Rat versus Mouse Primary Cerebellar Cell Cultures. Brain Sci 2019; 9:brainsci9120359. [PMID: 31817561 PMCID: PMC6955918 DOI: 10.3390/brainsci9120359] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/01/2019] [Accepted: 12/04/2019] [Indexed: 12/31/2022] Open
Abstract
The endocrine system of animals consists of fine-tuned self-regulating mechanisms that maintain the hormonal and neuronal milieu during tissue development. This complex system can be influenced by endocrine disruptors (ED)—substances that can alter the hormonal regulation even in small concentrations. By now, thousands of substances—either synthesized by the plastic, cosmetic, agricultural, or medical industry or occurring naturally in plants or in polluted groundwater—can act as EDs. Their identification and testing has been a hard-to-solve problem; Recent indications that the ED effects may be species-specific just further complicated the determination of biological ED effects. Here we compare the effects of bisphenol-A, zearalenone, and arsenic (well-known EDs) exerted on mouse and rat neural cell cultures by measuring the differences of the ED-affected neural estrogen- and thyroid receptors. EDs alters the receptor expression in a species-like manner detectable in the magnitude as well as in the nature of biological responses. It is concluded that the interspecies differences (or species specificity) in ED effects should be considered in the future testing of ED effects.
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Ashrap P, Sánchez BN, Téllez-Rojo MM, Basu N, Tamayo-Ortiz M, Peterson KE, Meeker JD, Watkins DJ. In utero and peripubertal metals exposure in relation to reproductive hormones and sexual maturation and progression among girls in Mexico City. ENVIRONMENTAL RESEARCH 2019; 177:108630. [PMID: 31421446 PMCID: PMC6734930 DOI: 10.1016/j.envres.2019.108630] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 07/23/2019] [Accepted: 08/04/2019] [Indexed: 05/08/2023]
Abstract
There is increasing evidence that several metals are endocrine disrupting chemicals (EDCs). In utero development and adolescence are critical windows of susceptibility to EDC exposure. With the exception of a few heavy metals, few human studies have evaluated the impact of metal exposure on pubertal development. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone levels and sexual maturation and progression among girls from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts. We measured urinary concentrations of aluminum (Al), arsenic (As), barium (Ba), cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), antimony (Sb), selenium (Se), and zinc (Zn) in samples collected from women during their third trimester of pregnancy and from their female children at 8-13 years (n = 132). We measured serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG) at age 8-13, and assessed Tanner stages for sexual maturation (breast, pubic hair development, and menarche status), at two time points (8-13, 14-18 years). We used linear regression to independently examine in utero and peripubertal metal concentrations as predictors of peripubertal hormones. In a longitudinal analysis using generalized estimation equations, we evaluated Tanner stage and menarche progression in relation to individual in utero and peripubertal metal concentrations. We found that higher in utero Zn was associated with increased inhibin B. Several metals at 8-13 years were associated with higher DHEA-S and estradiol, while Ni was positively but Cu was negatively associated with testosterone. In utero Ni, Al, and Cd were associated with slower progression of breast development after adjustment for child age and BMI z-score. For example, an IQR increase in in utero Al exposure was associated with 0.82 times lower odds of progressing to a higher Tanner stage for breast development per year (95% CI: 0.68, 0.99). Peripubertal concentrations of Ba and Al were also associated with being at a higher pubic hair Tanner stage and menarche at 8-13, but lower odds of progressing to the next stage at 14-18 years. We used Bayesian kernel machine regression (BKMR) to model the joint effect of multiple metals while accounting for correlated exposures, as well as potential non-linear relationships between metals and outcomes of interest, which yielded results similar to individual analyses. These findings suggest that female reproductive development may be vulnerable to the effects of metal exposure, and using both Tanner stages and hormone levels may provide clues about underlying mechanisms in two sensitive periods of development.
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Affiliation(s)
- Pahriya Ashrap
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, United States
| | - Brisa N Sánchez
- Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, MI, United States
| | - Martha M Téllez-Rojo
- Center for Nutrition and Health Research, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
| | - Niladri Basu
- Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Quebec, Canada
| | - Marcela Tamayo-Ortiz
- Center for Nutrition and Health Research, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico; Mexican Council for Science and Technology, Mexico City, Mexico
| | - Karen E Peterson
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI, United States
| | - John D Meeker
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, United States
| | - Deborah J Watkins
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, United States.
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10
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Souza ACF, Ervilha LOG, Coimbra JLP, Bastos DSS, Guimarães SEF, Machado-Neves M. Reproductive disorders in female rats after prenatal exposure to sodium arsenite. J Appl Toxicol 2019; 40:214-223. [PMID: 31429093 DOI: 10.1002/jat.3897] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/27/2019] [Accepted: 07/30/2019] [Indexed: 11/07/2022]
Abstract
Arsenic is a metalloid widely found in the environment in organic and inorganic forms. Exposure to inorganic arsenic forms via drinking water has been associated with an increased incidence of negative health effects, including reproductive disorders and dysfunction of the endocrine system. However, the impact of arsenic exposure on female reproductive development is still unclear. Therefore, in the present study, we evaluated the effects of prenatal exposure to arsenic on the initial sexual development and puberty onset, and in the morphology of the female reproductive organs, estrous cycle regularity and fertility parameters during adulthood. To do that, pregnant female Wistar rats were exposed to 10 mg/L sodium arsenite via drinking water from gestational day (GD) 1 until GD 21 and the female offspring was evaluated in different postnatal days. Our results showed that prenatal arsenic exposure induced a decrease of litter weight and morphological masculinization in females at postnatal day 1. Moreover, these females had a delay in the age of puberty onset and alteration in estrous cycle number and length. During adulthood, females from the sodium arsenite group showed an increase in endometrium, myometrium and perimetrium areas, and an imbalance in uterine antioxidant enzyme activity. These animals also presented an increase in post-implantation loss and reabsorption number, leading to reduced viable fetus number. In conclusion, prenatal arsenic exposure in rats was able to promote female masculinization, alter sexual development and impair reproductive performance.
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Affiliation(s)
- Ana Cláudia Ferreira Souza
- Department of Animal Biology, Universidade Federal Rural do Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | | | | | | | | | - Mariana Machado-Neves
- Department of General Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
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11
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Sims KC, Schwendinger KL, Szymkowicz DB, Swetenburg JR, Bain LJ. Embryonic arsenic exposure reduces intestinal cell proliferation and alters hepatic IGF mRNA expression in killifish (Fundulus heteroclitus). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2019; 82:142-156. [PMID: 30729860 PMCID: PMC6397093 DOI: 10.1080/15287394.2019.1571465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Arsenic (As) is a toxicant found in food and water throughout the world, and studies suggested that exposure early in life reduces growth. Thus, the goal of this study was to examine mechanisms by which As impacted organismal growth. Killifish (Fundulus heteroclitus) were exposed to 0, 10, 50, or 200 ppb As as embryos and, after hatching, were reared in clean water for up to 40 weeks. Metabolism studies revealed that killifish biotransform As such that monomethylated and dimethylated arsenicals account for 15-17% and 45-61%, respectively, of the total metal. Growth, as measured by condition factor (CF), was significantly and dose-dependently reduced at 8 weeks of age but was similar to controls by 40 weeks. To determine mechanisms underlying the observed initial decrease, intestinal proliferation and morphology were examined. Arsenic-exposed fish exhibited significant 1.3- to 1.5-fold reduction in intestinal villus height and 1.4- to 1.6-fold decrease in proliferating cell nuclear antigen (PCNA+) intestinal cells at all weeks examined. In addition, there were significant correlations between CF, PCNA+ cells, and intestinal villus height. Upon examining whether fish might compensate for the intestinal changes, it was found that hepatic mRNA expression of insulin-like growth factor 1 (IGF-1) and its binding protein (IGFBP-1) were dose-dependently increased. These results indicate that embryonic exposure initially diminished growth, and while intestinal cell proliferation remained reduced, fish appear to compensate by enhancing transcript levels of hepatic IGF-1 and IGFBP-1.
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Affiliation(s)
- Kaleigh C. Sims
- Environmental Toxicology Graduate Program, Clemson University, Clemson, SC, USA
| | | | - Dana B. Szymkowicz
- Environmental Toxicology Graduate Program, Clemson University, Clemson, SC, USA
| | | | - Lisa J. Bain
- Environmental Toxicology Graduate Program, Clemson University, Clemson, SC, USA
- Department of Biological Sciences, Clemson University, Clemson, SC, USA
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12
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da Cunha de Medeiros P, Samelo RR, Silva APG, da Silva Araujo Santiago M, Duarte FA, de Castro ÍB, Perobelli JE. Prepubertal exposure to low doses of sodium arsenite impairs spermatogenesis and epididymal histophysiology in rats. ENVIRONMENTAL TOXICOLOGY 2019; 34:83-91. [PMID: 30291770 DOI: 10.1002/tox.22660] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 09/14/2018] [Accepted: 09/16/2018] [Indexed: 06/08/2023]
Abstract
For the first time, juvenile toxicity of inorganic arsenic (As) was investigated in male rats, focusing on reproductive effects. As is a metalloid naturally occurring in the environment, being the inorganic forms the most toxics. Contaminated drinking water and agricultural products are the main prospectors of intoxication for general population. In the present study, Wistar male rats (21 days old) were distributed into three groups (n = 10/group): control (received vehicle-filtered drinking water), As1 (received AsNaO2 at 0.01 mg L-1 ) and As2 (received AsNaO2 at 10 mg L-1 ). The animals were euthanized on PND 53. Testicular damages increased in As1 and As2 compared to control (ie, presence of vacuolization, acidophilic cells, and epithelium degeneration). Testicular interstitium of As1 and As2 presented fluid's increase and intense inflammatory infiltration. In the epididymis there was reduction of sperm amount in the lumen, besides epithelium areas presenting cribriform aspect in As1 and As2, exfoliation of cells in the light (in As1) and vacuoles (in As2). In epididymis interstitium, inflammatory infiltrates were observed in initial segment of As1 and As2. AsNaO2 changed immunolabeling pattern for androgen receptor in epididymis of As2, although serum testosterone levels was statistically comparable to control. Mass spectrometry revealed higher As concentrations in testis and epididymis of As2 compared to As1 and Control. These results indicate compromise of spermatogenesis and epididymal histophysiology in AsNaO2 -treated animals, possibly impairing sperm quality and fertility in long-term, even at low levels of exposure. Investigations about the reversibility of reproductive damages are necessary to better understand the mechanisms of As reproductive toxicity.
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Affiliation(s)
- Paloma da Cunha de Medeiros
- Laboratório de Toxicologia Experimental-LATOEX, Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Campus Baixada Santista, Santos, São Paulo, Brazil
| | - Ricardo Rodrigues Samelo
- Laboratório de Toxicologia Experimental-LATOEX, Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Campus Baixada Santista, Santos, São Paulo, Brazil
| | - Ana Priscila Gomes Silva
- Laboratório de Toxicologia Experimental-LATOEX, Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Campus Baixada Santista, Santos, São Paulo, Brazil
| | - Marcella da Silva Araujo Santiago
- Laboratório de Toxicologia Experimental-LATOEX, Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Campus Baixada Santista, Santos, São Paulo, Brazil
| | - Fabio Andrei Duarte
- Departamento de Química, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - Ítalo Braga de Castro
- Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Campus Baixada Santista, Santos, São Paulo, Brazil
| | - Juliana Elaine Perobelli
- Laboratório de Toxicologia Experimental-LATOEX, Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Campus Baixada Santista, Santos, São Paulo, Brazil
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13
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Manthari RK, Tikka C, Ommati MM, Niu R, Sun Z, Wang J, Zhang J, Wang J. Arsenic-Induced Autophagy in the Developing Mouse Cerebellum: Involvement of the Blood-Brain Barrier's Tight-Junction Proteins and the PI3K-Akt-mTOR Signaling Pathway. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:8602-8614. [PMID: 30032600 DOI: 10.1021/acs.jafc.8b02654] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This study was designed to determine whether the tight-junction (TJ) proteins of the blood-brain barrier (BBB) and the PI3K-Akt-mTOR signaling pathway are involved during arsenic (As)-induced autophagy in developing mouse cerebella after exposure to different As concentrations (0, 0.15, 1.5, and 15 mg/L As(III)) during gestational and lactational periods. The dosage was continually given to the pups until postnatal day (PND) 42. Studies conducted at different developmental age points, like PND21, 28, 35, and 42, showed that exposure to As led to a significant decrease in the mRNA-expression levels of TJ proteins (occludin, claudin, ZO-1, and ZO-2), PI3K, Akt, mTOR, and p62, with concomitant increases in Beclin1, LC3I, LC3II, Atg5, and Atg12. Also, As significantly downregulated occludin and mTOR protein-expression levels with concomitant upregulation of Beclin1, LC3, and Atg12 at all the developmental age points. However, no significant alterations were observed in low- and medium-dose-exposed groups at PND42. Histopathological analysis revealed the irregular arrangement of the Purkinje cell layer in the As-exposed mice. Ultrastructural analysis by transmission electron microscopy (TEM) revealed the occurrence of autophagosomes and vacuolated axons in the cerebella of the mice exposed to high doses of As at PND21 and 42, respectively. Finally, we conclude that developmental As exposure significantly alters TJ proteins, resulting an increase in BBB permeability, facilitating the ability of As to cross the BBB and induce autophagy, which might be partly the result of inhibition of the PI3K-Akt-mTOR signaling pathway, in an age-dependent manner (i.e., PND21 mice were found to be more vulnerable to As-induced neurotoxicity), which could be due to the immature BBB allowing As to cross through it. However, the effect was not significant in PND42, which could be due to the developed BBB.
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Affiliation(s)
- Ram Kumar Manthari
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
| | - Chiranjeevi Tikka
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
| | - Mohammad Mehdi Ommati
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
- Department of Animal Science, College of Agriculture , Shiraz University , Shiraz 71441-65186 , Iran
| | - Ruiyan Niu
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
| | - Zilong Sun
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
| | - Jinming Wang
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
| | - Jianhai Zhang
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
| | - Jundong Wang
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine , Shanxi Agricultural University , Taigu , Shanxi 030801 , China
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14
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Li X, Sun Z, Manthari RK, Li M, Guo Q, Wang J. Effect of gestational exposure to arsenic on puberty in offspring female mice. CHEMOSPHERE 2018; 202:119-126. [PMID: 29567609 DOI: 10.1016/j.chemosphere.2018.03.095] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/07/2018] [Accepted: 03/14/2018] [Indexed: 06/08/2023]
Abstract
We examined the vaginal opening day, ovary and uterus organ coefficient, reproductive hormone levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH), mRNA and protein expression levels of kiss-1, hypothalamus gonadotrophin releasing hormone 1 (GnRH1), organic cation transporters 2 (Oct2) and transcription termination factor 1 (Ttf1) in different pubertal ages [late lactation (18 days), pre-puberty (21-22 days), puberty (23-27 days; with respect to vaginal opening) and maturity (65 days)] of offspring females, to evaluate the effect of arsenic (As) on puberty initiation after maternal exposure to As at different concentration [0, 0.15, 1.5 and 15 mg/L As(III)] during gestational period. The results showed that the vaginal opening time was significantly advanced in utero in mice exposed to As compared to the control. The hormone level of LH was significantly increased in the mice treated with 15 mg/L of As(III) at puberty compared to the control. During puberty, the mRNA expression levels of kiss-1, GnRH1, Oct2 and Ttf1 in the hypothalamus were significantly increased in the group treated with 15 mg/L of As(III) compared to the control. The protein expressions of Kisspeptin, GnRH1, Oct2 and Ttf1 in the hypothalamus were significantly increased in the pubertal females, while Oct2 and Ttf1 expression levels were significantly decreased in the matured females compared to the control, which is in line with the transcriptional changes of related mRNA expressions. In brief, this study demonstrated that maternal exposure to As during gestational period could result in early onset of puberty in offspring females.
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Affiliation(s)
- Xuehua Li
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China
| | - Zilong Sun
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China
| | - Ram Kumar Manthari
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China
| | - Meiyan Li
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China
| | - Qiang Guo
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China
| | - Jundong Wang
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China.
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15
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Szymkowicz DB, Sims KC, Castro NM, Bridges WC, Bain LJ. Embryonic-only arsenic exposure in killifish (Fundulus heteroclitus) reduces growth and alters muscle IGF levels one year later. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2017; 186:1-10. [PMID: 28237603 PMCID: PMC5395342 DOI: 10.1016/j.aquatox.2017.02.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Revised: 02/16/2017] [Accepted: 02/17/2017] [Indexed: 05/06/2023]
Abstract
Arsenic is a contaminant of drinking water and crops in many parts of the world. Epidemiological studies have shown that arsenic exposure is linked to decreased birth weight, weight gain, and proper skeletal muscle function. The goal of this study was to use killifish (Fundulus heteroclitus) as a model to determine the long-term effects of embryonic-only arsenic exposure on muscle growth and the insulin-like growth factor (IGF) pathway. Killifish embryos were exposed to 0, 50, 200 or 800ppb AsIII from fertilization until hatching. Juvenile fish were reared in clean water and muscle samples were collected at 16, 28, 40 and 52 weeks of age. There were significant reductions in condition factors, ranging from 12 to 17%, in the fish exposed to arsenic at 16, 28 and 40 weeks of age. However, by 52 weeks, no significant changes in condition factors were seen. Alterations in IGF-1R and IGF-1 levels were assessed as a potential mechanism by which growth was reduced. While there no changes in hepatic IGF-1 transcripts, skeletal muscle cells can also produce their own IGF-1 and/or alter IGF-1 receptor levels to help enhance growth. After a 200 and 800ppb embryonic exposure, fish grown in clean water for 16 weeks had IGF-1R transcripts that were 2.8-fold and 2-fold greater, respectively, than unexposed fish. Through 40 weeks of age, IGF1-R remained elevated in the 200ppb and 800ppb embryonic exposure groups by 1.8-3.9-fold, while at 52 weeks of age, IGF-1R levels were still significantly increased in the 800ppb exposure group. Skeletal muscle IGF-1 transcripts were also significantly increased by 1.9-5.1 fold through the 52 weeks of grow-out in clean by water in the 800ppb embryonic exposure group. Based on these results, embryonic arsenic exposure has long-term effects in that it reduces growth and increases both IGF-1 and IGF-1R levels in skeletal muscle even 1year after the exposure has ended.
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MESH Headings
- Animals
- Arsenic/toxicity
- Behavior, Animal/drug effects
- Embryonic Development/drug effects
- Environmental Exposure/analysis
- Female
- Fundulidae/embryology
- Fundulidae/genetics
- Fundulidae/growth & development
- Gene Expression Regulation, Developmental/drug effects
- Insulin-Like Growth Factor I/genetics
- Insulin-Like Growth Factor I/metabolism
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Pregnancy
- Prenatal Exposure Delayed Effects/genetics
- Prenatal Exposure Delayed Effects/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Water Pollutants, Chemical/toxicity
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Affiliation(s)
- Dana B Szymkowicz
- Environmental Toxicology Graduate Program, Clemson University, Clemson, SC, United States
| | - Kaleigh C Sims
- Environmental Toxicology Graduate Program, Clemson University, Clemson, SC, United States
| | - Noemi M Castro
- Department of Biochemistry and Molecular Biology, University of California-Davis, Davis, CA, United States
| | - William C Bridges
- Department of Mathematical Sciences, Clemson University, Clemson, SC, United States
| | - Lisa J Bain
- Environmental Toxicology Graduate Program, Clemson University, Clemson, SC, United States; Department of Biological Sciences, Clemson University, Clemson, SC, United States.
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16
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Williams AL, DeSesso JM. Comment on "Effects of in Utero Exposure to Arsenic during the Second Half of Gestation on Reproductive End Points and Metabolic Parameters in Female CD-1 Mice". ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:A46. [PMID: 26930347 PMCID: PMC4786992 DOI: 10.1289/ehp.1511031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Amy L. Williams
- Address correspondence to A.L. Williams, Exponent, Inc., 1800 Diagonal Rd., Ste. 500, Alexandria, VA 22314 USA. E-mail:
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17
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Rodriguez KF, Ungewitter EK, Crespo-Mejias Y, Liu C, Nicol B, Kissling GE, Yao HHC. Effects of in Utero Exposure to Arsenic during the Second Half of Gestation on Reproductive End Points and Metabolic Parameters in Female CD-1 Mice. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:336-43. [PMID: 26295903 PMCID: PMC4786990 DOI: 10.1289/ehp.1509703] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 08/17/2015] [Indexed: 05/19/2023]
Abstract
BACKGROUND Mice exposed to high levels of arsenic in utero have increased susceptibility to tumors such as hepatic and pulmonary carcinomas when they reach adulthood. However, the effects of in utero arsenic exposure on general physiological functions such as reproduction and metabolism remain unclear. OBJECTIVES We evaluated the effects of in utero exposure to inorganic arsenic at the U.S. Environmental Protection Agency (EPA) drinking water standard (10 ppb) and at tumor-inducing levels (42.5 ppm) on reproductive end points and metabolic parameters when the exposed females reached adulthood. METHODS Pregnant CD-1 mice were exposed to sodium arsenite [none (control), 10 ppb, or 42.5 ppm] in drinking water from gestational day 10 to birth, the window of organ formation. At birth, exposed offspring were fostered to unexposed dams. We examined reproductive end points (age at vaginal opening, reproductive hormone levels, estrous cyclicity, and fertility) and metabolic parameters (body weight changes, hormone levels, body fat content, and glucose tolerance) in the exposed females when they reached adulthood. RESULTS Arsenic-exposed females (10 ppb and 42.5 ppm) exhibited early onset of vaginal opening. Fertility was not affected when females were exposed to the 10-ppb dose. However, the number of litters per female was decreased in females exposed to 42.5 ppm of arsenic in utero. In both 10-ppb and 42.5-ppm groups, arsenic-exposed females had significantly greater body weight gain, body fat content, and glucose intolerance. CONCLUSION Our findings revealed unexpected effects of in utero exposure to arsenic: exposure to both a human-relevant low dose and a tumor-inducing level led to early onset of vaginal opening and to obesity in female CD-1 mice.
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Affiliation(s)
- Karina F. Rodriguez
- Reproductive Developmental Biology Group, Reproductive and Developmental Biology Laboratory, and
| | - Erica K. Ungewitter
- Reproductive Developmental Biology Group, Reproductive and Developmental Biology Laboratory, and
| | - Yasmin Crespo-Mejias
- Reproductive Developmental Biology Group, Reproductive and Developmental Biology Laboratory, and
| | - Chang Liu
- Reproductive Developmental Biology Group, Reproductive and Developmental Biology Laboratory, and
| | - Barbara Nicol
- Reproductive Developmental Biology Group, Reproductive and Developmental Biology Laboratory, and
| | - Grace E. Kissling
- Biostatistics Branch, National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Humphrey Hung-Chang Yao
- Reproductive Developmental Biology Group, Reproductive and Developmental Biology Laboratory, and
- Address correspondence to H.H.-C. Yao, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services, 111 T.W. Alexander Dr., C4-10, Research Triangle Park, NC 27709 USA, Telephone: (919) 541-1095. E-mail:
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18
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Ditzel EJ, Li H, Foy CE, Perrera AB, Parker P, Renquist BJ, Cherrington NJ, Camenisch TD. Altered Hepatic Transport by Fetal Arsenite Exposure in Diet-Induced Fatty Liver Disease. J Biochem Mol Toxicol 2016; 30:321-30. [PMID: 26890134 DOI: 10.1002/jbt.21796] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/09/2016] [Accepted: 01/15/2016] [Indexed: 12/21/2022]
Abstract
Non-alcoholic fatty liver disease can result in changes to drug metabolism and disposition potentiating adverse drug reactions. Furthermore, arsenite exposure during development compounds the severity of diet-induced fatty liver disease. This study examines the effects of arsenite potentiated diet-induced fatty liver disease on hepatic transport in male mice. Changes were detected for Mrp2/3/4 hepatic transporter gene expression as well as for Oatp1a4/2b1/1b2. Plasma concentrations of Mrp and Oatp substrates were increased in arsenic exposure groups compared with diet-only controls. In addition, murine embryonic hepatocytes and adult primary hepatocytes show significantly altered transporter expression after exposure to arsenite alone: a previously unreported phenomenon. These data indicate that developmental exposure to arsenite leads to changes in hepatic transport which could increase the risk for ADRs during fatty liver disease.
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Affiliation(s)
- Eric J Ditzel
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ, 85721, USA.
| | - Hui Li
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ, 85721, USA
| | - Caroline E Foy
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, 85721, USA
| | - Alec B Perrera
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ, 85721, USA
| | - Patricia Parker
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ, 85721, USA
| | - Benjamin J Renquist
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, 85721, USA
| | - Nathan J Cherrington
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ, 85721, USA.,Southwest Environmental Health Sciences Center, The University of Arizona, Tucson, AZ, 85721, USA
| | - Todd D Camenisch
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ, 85721, USA.,Southwest Environmental Health Sciences Center, The University of Arizona, Tucson, AZ, 85721, USA.,Steele Children's Research Center, Arizona Health Sciences Center, The University of Arizona, Tucson, AZ, 85724, USA.,Sarver Heart Center, The University of Arizona, Tucson, AZ, 85724, USA.,Bio5 Institute, The University of Arizona, Tucson, AZ, 85721, USA
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19
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Ditzel EJ, Nguyen T, Parker P, Camenisch TD. Effects of Arsenite Exposure during Fetal Development on Energy Metabolism and Susceptibility to Diet-Induced Fatty Liver Disease in Male Mice. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:201-9. [PMID: 26151952 PMCID: PMC4749082 DOI: 10.1289/ehp.1409501] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 07/02/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND Chronic exposure to arsenicals at various life stages and across a range of exposures has been implicated in cardiometabolic and liver disease, but disease predisposition from developmental exposures remains unclear. OBJECTIVES In utero and post-weaning exposure to trivalent arsenic (AsIII) was examined on the background of a Western-style diet to determine whether AsIII exposure affects metabolic disease. METHODS Male Swiss Webster mice were exposed to 100 ppb AsIII in utero, after weaning, or both. Ad libitum access to a Western-style diet was provided after weaning, and the plasma metabolome, liver histopathology, liver enzyme activity, and gene expression were analyzed. RESULTS Hepatic lipid composition and histopathology revealed that developmental AsIII exposure exacerbated Western-style diet-induced fatty liver disease. Continuous AsIII exposure increased cardiometabolic risk factors including increased body weight, insulin resistance, hyperglycemia, and plasma triglycerides. AsIII exposure produced a decrease in the intermediates of glycolysis and the TCA cycle while increasing ketones. Hepatic isocitrate dehydrogenase activity was also decreased, which confirmed disruption of the TCA cycle. Developmental AsIII exposure increased the expression of genes involved in fatty acid synthesis, lipogenesis, inflammation, and packaging of triglycerides, suggesting an increased acetyl coenzyme A (acetyl-CoA) load. CONCLUSIONS In utero and continuous early-life exposure to AsIII disrupted normal metabolism and elevated the risk for fatty liver disease in mice maintained on a high-fat diet. Our findings suggest that individuals exposed to AsIII during key developmental periods and who remain exposed to AsIII on the background of a Western-style diet may be at increased risk for metabolic disease later in life.
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Affiliation(s)
- Eric J. Ditzel
- Department of Pharmacology and Toxicology, College of Pharmacy,
| | - Thu Nguyen
- Department of Pharmacology and Toxicology, College of Pharmacy,
| | - Patricia Parker
- Department of Pharmacology and Toxicology, College of Pharmacy,
| | - Todd D. Camenisch
- Department of Pharmacology and Toxicology, College of Pharmacy,
- Steele Children’s Research Center,
- Southwest Environmental Health Sciences Center,
- Sarver Heart Center, and
- Bio5 Institute, University of Arizona, Tucson, Arizona, USA
- Address correspondence to T.D. Camenisch, 1703 E. Mabel St., P.O. Box 210207, Tucson, AZ 85721 USA. Telephone: (520) 626-0240. E-mail:
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Delay of the onset of puberty in female rats by prepubertal exposure to T-2 toxin. Toxins (Basel) 2015; 7:4668-83. [PMID: 26569305 PMCID: PMC4663527 DOI: 10.3390/toxins7114668] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Revised: 10/06/2015] [Accepted: 10/23/2015] [Indexed: 01/31/2023] Open
Abstract
Growing evidence has revealed the deleterious influence of environmental and food contaminants on puberty onset and development in both animals and children, provoking an increasing health concern. T-2 toxin, a naturally-produced Type A trichothecene mycotoxin which is frequently found in cereal grains and products intended for human and animal consumption, has been shown to impair the reproduction and development in animals. Nevertheless, whether this trichothecene mycotoxin can disturb the onset of puberty in females remains unclear. To clarify this point, infantile female rats were given a daily intragastric administration of vehicle or 187.5 μg/kg body weight of T-2 toxin for five consecutive days from postnatal day 15 to 19, and the effects on puberty onset were evaluated in the present study. The results revealed that the days of vaginal opening, first dioestrus, and first estrus in regular estrous cycle were delayed following prepubertal exposure to T-2 toxin. The relative weights of reproductive organs uterus, ovaries, and vagina, and the incidence of corpora lutea were all diminished in T-2 toxin-treated rats. Serum levels of gonadotropins luteinizing hormone, follicle-stimulating hormone, and estradiol were also reduced by T-2 toxin treatment. The mRNA expressions of hypothalamic gonadotropin-releasing hormone (GnRH) and pituitary GnRH receptor displayed significant reductions following exposure to T-2 toxin, which were consistent with the changes of serum gonadotropins, delayed reproductive organ development, and delayed vaginal opening. In conclusion, the present study reveals that prepubertal exposure to T-2 toxin delays the onset of puberty in immature female rats, probably by the mechanism of disturbance of hypothalamic-pituitary-gonadal (HPG) axis function. Considering the vulnerability of developmental children to food contaminants and the relative high level of dietary intake of T-2 toxin in children, we think the findings of the present study provide valuable information for the health risk assessment in children.
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Parodi DA, Greenfield M, Evans C, Chichura A, Alpaugh A, Williams J, Martin MB. Alteration of mammary gland development and gene expression by in utero exposure to arsenic. Reprod Toxicol 2015; 54:66-75. [PMID: 25543096 PMCID: PMC4465030 DOI: 10.1016/j.reprotox.2014.12.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 12/07/2014] [Accepted: 12/16/2014] [Indexed: 01/02/2023]
Abstract
Early life exposure to estrogens and estrogen like contaminants in the environment is thought to contribute to the early onset of puberty and consequently increases the risk of developing breast cancer in the exposed female. The results of this study show that in utero exposure to the metalloestrogen arsenite altered mammary gland development prior to its effect on puberty onset. In the prepubertal gland, in utero exposure resulted in an increase in the number of mammosphere-forming cells and an increase in branching, epithelial cells, and density. In the postpubertal gland, in utero exposure resulted in the overexpression of estrogen receptor-alpha (ERα) that was due to the increased and altered response of the ERα transcripts derived from exons O and OT to estradiol. These results suggest that, in addition to advancing puberty onset, in utero exposure to arsenite alters the pre- and postpubertal development of the mammary gland and possibly, the risk of developing breast cancer.
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Affiliation(s)
- Daniela A Parodi
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC 20007, USA
| | - Morgan Greenfield
- Department of Oncology, Georgetown University, Washington, DC 20007, USA
| | - Claire Evans
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC 20007, USA
| | - Anna Chichura
- Department of Oncology, Georgetown University, Washington, DC 20007, USA
| | - Alexandra Alpaugh
- Department of Oncology, Georgetown University, Washington, DC 20007, USA
| | - James Williams
- Department of Oncology, Georgetown University, Washington, DC 20007, USA
| | - Mary Beth Martin
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC 20007, USA; Department of Oncology, Georgetown University, Washington, DC 20007, USA.
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22
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Stanko JP, Easterling MR, Fenton SE. Application of Sholl analysis to quantify changes in growth and development in rat mammary gland whole mounts. Reprod Toxicol 2014; 54:129-35. [PMID: 25463529 DOI: 10.1016/j.reprotox.2014.11.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 10/07/2014] [Accepted: 11/07/2014] [Indexed: 10/24/2022]
Abstract
Studies that utilize the rodent mammary gland (MG) as an endpoint for assessing the developmental toxicity of chemical exposures typically employ either basic dimensional measurements or developmental scoring of morphological characteristics as a means to quantify MG development. There are numerous means by which to report these developmental changes, leading to inconsistent translation across laboratories. The Sholl analysis is a method historically used for quantifying neuronal dendritic patterns. The present study describes the use of the Sholl analysis to quantify MG branching characteristics. Using this method, we were able to detect significant differences in branching density in MG of peripubertal female Sprague Dawley rats that had been exposed to vehicle or a potent estrogen. These data suggest the Sholl analysis can be an effective tool for quantitatively measuring an important characteristic of MG development and for examining associations between MG growth and density and adverse effects in the breast.
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Affiliation(s)
- Jason P Stanko
- National Toxicology Program Laboratory, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, United States
| | | | - Suzanne E Fenton
- National Toxicology Program Laboratory, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, United States.
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Dearth RK, Hiney JK, Srivastava VK, Hamilton AM, Dees WL. Prepubertal exposure to elevated manganese results in estradiol regulated mammary gland ductal differentiation and hyperplasia in female rats. Exp Biol Med (Maywood) 2014; 239:871-882. [PMID: 24845367 DOI: 10.1177/1535370214531865] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Evidence suggests that environmental substances regulating estrogenic pathways during puberty may be detrimental to the developing mammary gland (MG). Manganese (Mn) is a trace mineral required for normal physiological processes. Prepubertal exposure to Mn induces precocious puberty in rats, an event associated with early elevations in puberty-related hormones, including estradiol (E2). However, until now the effect of Mn-induced precocious MG development has not been determined. Therefore, we assessed the ability of prepubertal Mn exposure to advance normal MG development and alter E2 driven pathways involved in tumorigenesis. Sprague Dawley female rats were gavaged daily with either 10 mg/kg manganese chloride (MnCl2) or saline (control) from postnatal day (PND) 12 through PND 30. Blood and MGs were collected on PNDs 30 and 120. Compared to controls, serum E2 levels on PND 30 were elevated (p < 0.05) in the Mn-treated group. Mn exposure significantly increased differentiated MG terminal ductal structures and the percentage of MG epithelial cells that stained positive for the proliferative marker, Ki67, at PND 30 (p < 0.001) and PND 120 (p < 0.001). Levels of Mn (ppm) were not elevated in these MGs. Mn-treated animals (40%) exhibited reactive stroma and intra-luminal focal hyperplasia in hemotoxylin and eosin stained MGs at PND 120. Furthermore, Mn exposure resulted in elevated protein expression levels of estrogen receptor α, activator protein 2α, phosphorylated (p)-Akt, and p53 in MGs on PND 120, but not on PND 30. Collectively, these data show that exposure to a supplemental dose of Mn causes accelerated pubertal MG growth which can progress to adult hyperplasia; thus, providing evidence that early life Mn exposure may increase susceptibility to breast cancer.
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Affiliation(s)
- Robert K Dearth
- Department of Biology, College of Science and Mathematics, University of Texas-Pan American, Edinburg, TX 78539, USA
| | - Jill K Hiney
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4458, USA
| | - Vinod K Srivastava
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4458, USA
| | - Alina M Hamilton
- Department of Biology, College of Science and Mathematics, University of Texas-Pan American, Edinburg, TX 78539, USA
| | - William L Dees
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4458, USA
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