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Rashid F, Singh D, Attri S, Kaur P, Kaur H, Mohana P, Quadar J, Vig AP, Bhatia A, Singh B, Walia H, Arora S. Modulation of atrazine-induced chromosomal aberrations and cyclin-dependent kinases by aqueous extract of Roylea cinerea (D.Don) Baillon leaves in Allium cepa. Sci Rep 2022; 12:12570. [PMID: 35869268 PMCID: PMC9307653 DOI: 10.1038/s41598-022-16813-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/15/2022] [Indexed: 11/10/2022] Open
Abstract
Roylea cinerea (D.Don) Baillon an indigenous medicinal plant of Lamiaceae family used for the treatment of several diseases. In the present study, its aqueous (leaves) extract was tested for genoprotective action against atrazine-induced chromosomal aberrations in the root tip cells of Allium cepa. Atrazine is a herbicide of triazine class commonly used to inhibit the growth of broad leaf and grassy weeds. In order to find the concentration of atrazine that exhibits maximum toxicity, its different concentrations (1, 5 and 10 µg/mL) were tested. It was observed that 10 µg/mL concentration was more toxic as it reduced the mitotic index and also increased the chromosomal aberrations. Among all the tested concentrations of aqueous (leaves) extracts (0.25. 0.5, 1.0, 1.5 and 3.0 µg/mL), the3.0 µg/mL concentration in both modes of experiments i.e. pre and post showed a significant reduction in chromosomal aberrations induced by atrazine. To understand the mechanism of protection by plant extract on atrazine-induced chromosomal abnormalities the RT-qPCR studies were conducted to observe the expression of marker genes Cyclin-dependent kinases (CDKs) (CDKA:1, CDKB2:1 and CDKD1:1. For this, the RNA was extracted from root tips treated with extract along with atrazine by TRIzol®. It was observed that aqueous extract of Roylea cinerea (D.Don) Baillon leaves upregulated the CDKs gene expression in both the modes i.e. pre and post treatments. A critical analysis of results indicated that aqueous extract ameliorated the chromosomal aberrations caused by atrazine which may be be due to the increased expression level of CDKs genes.
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Sex Dependent Action of Aroclor 1254 on Basal and sGnRHa-Stimulated Secretion of LH from the Pituitary Cells of Common Carp, Cyprinus carpio L. ANNALS OF ANIMAL SCIENCE 2021. [DOI: 10.2478/aoas-2020-0104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Polychlorinated biphenyls (PCBs) affect the hypothalamic-pituitary-gonadal axis in many vertebrates, changing the hormonal regulation of reproduction. To identify one of the possible sites of action of PCBs on gonadotropin release in common carp, the direct effects of Aroclor 1254 on luteinizing hormone (LH) secretion from dispersed pituitary cells were investigated. Pituitary cells were obtained from sexually mature male and female common carp (Cyprinus carpio L.) at the time of natural spawning. The cells were incubated with different concentrations of Aroclor 1254 (5, 10, 50 and 100 ng mL–1 medium) and/or salmon gonadotropin-releasing hormone analogue (sGnRHa) at a concentration of 10−8 M. LH levels were measured in the cultured medium by the ELISA method after 10 hours of cell incubation. Incubation of male pituitary cells in the presence of tested concentrations of Aroclor did not change the basal LH secretion to the media. In the female pituitary cell incubations Aroclor (5, 10 and 100 ng mL–1 medium) caused a significant increase in LH concentrations in comparison to control incubations. In the case of sGnRHastimulated LH secretion in incubations of cells of both sexes, all the concentrations of Aroclor significantly stimulated LH release and potentiated stimulatory effects of sGnRH analogue. These results indicate that endocrine disrupters, such as Aroclor 1254, may affect reproduction in fish, acting also directly on gonadotrophs at the level of the pituitary gland, changing LH secretion.
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Carnevali O, Santangeli S, Forner-Piquer I, Basili D, Maradonna F. Endocrine-disrupting chemicals in aquatic environment: what are the risks for fish gametes? FISH PHYSIOLOGY AND BIOCHEMISTRY 2018; 44:1561-1576. [PMID: 29948447 DOI: 10.1007/s10695-018-0507-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Over the past 25 years, extensive research in vertebrate species has identified several genomic pathways altered by exposures to anthropogenic chemicals with hormone-like activity mediated by their interaction with nuclear receptors. In addition, many pollutants have been shown to interfere with non-genomic (non-classical) pathways, but this mechanism of endocrine disruption is still poorly understood. Recently, the number of publications describing the effects of Endocrine disrupting chemicals (EDCs) on fish reproduction, focusing on the deregulation of the hypothalamus-pituitary-gonadal axis as well as on gamete quality, significantly increased. Depending on their ability to mimic endogenous hormones, the may differently affect male or female reproductive physiology. Inhibition of gametogenesis, development of intersex gonads, alteration of the gonadosomatic index, and decreased fertility rate have been largely documented. In males, alterations of sperm density, motility, and fertility have been observed in several wild species. Similar detrimental effects were described in females, including negative outcomes on oocyte growth and maturation plus the occurrence of apoptotic/autophagic processes. These pathways may affect gamete viability considered as one of the major indicators of reproductive endocrine disruption. Pollutants act also at DNA level producing DNA mutations and changes in epigenetic pathways inducing specific mechanisms of toxicity and/or aberrant cellular responses that may affect subsequent generation(s) through the germline. In conclusion, this review summarizes the effects caused by EDC exposure on fish reproduction, focusing on gametogenesis, giving a general overview of the different aspects dealing with this issue, from morphological alteration, deregulation of steroidogenesis, hormonal synthesis, and occurrence of epigenetic process.
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Affiliation(s)
- Oliana Carnevali
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131, Ancona, Italy.
- INBB Consorzio Interuniversitario di Biostrutture e Biosistemi, 00136, Rome, Italy.
| | - Stefania Santangeli
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
- INBB Consorzio Interuniversitario di Biostrutture e Biosistemi, 00136, Rome, Italy
| | - Isabel Forner-Piquer
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Danilo Basili
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
| | - Francesca Maradonna
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131, Ancona, Italy.
- INBB Consorzio Interuniversitario di Biostrutture e Biosistemi, 00136, Rome, Italy.
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Fort DJ, Mathis MB, Guiney PD, Weeks JA. Inhibition of germinal vesicle breakdown in Xenopus oocytes in vitro by a series of substituted glycol ethers. J Appl Toxicol 2017; 38:628-637. [PMID: 29205417 DOI: 10.1002/jat.3567] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 09/28/2017] [Accepted: 10/16/2017] [Indexed: 01/31/2023]
Abstract
A 24 hour in vitro Xenopus oocyte maturation (germinal vesicle breakdown [GVBD]) assay developed by Pickford and Morris (Environmental Health Perspectives, 1999, 107, 285-292) was used to screen a series of substituted glycol ethers (GEs). Substituted GEs included: ethylene glycol monomethyl ether (EGME); EG monoethyl ether (EGEE); EG monopropyl ether (EGPE); EG monobutyl ether (EGBE); EG monohexyl ether (EGHE); diethylene glycol monomethyl ether (DGME); triethylene glycol monomethyl ether (TGME); ethylene glycol monophenyl ether (EGPhE); EG monobenzyl ether (EGBeE); EG diphenyl ether (EGDPhE); and propylene glycol monophenyl ether (PGPhE). The GEs inhibited progesterone- or androstenedione-induced GVBD with the following relative potency: EGPhE > PGPhE > EGME >> EGEE ≥ EGBeE > EGPE >> EGBE >EGHE > EGDPhE >> DGME ≥ TGME, or EGPhE >> PGPhE >> EGBeE > EGDPhE > EGEE > EGME > EGPE > EGBE, EGHE, DGME and TGME, respectively. Further, [3 H]progesterone or [3 H]androstenedione binding affinities to the oocyte plasma membrane progesterone receptor (OMPR) or classical androgen receptor (AR) were: EGME > EGPhE ≥ PGPhE ≥ EGEE > EGBeE >> EGPE >> EGBE ≥ EGHE > EGDPhE, TGME, and DGME, or EGPhE > PGPhE >> EGBeE > EGDPhE >> EGEE ≥ EGME >> EGPE, EGBE, and EGHE > DGME and TGME, respectively. Binary joint mixture studies with the GVBD model using flutamide (AR antagonist) and EGPhE indicated that flutamide/EGPhE mixture acted in a concentration additive manner. The effects of substituted GE series, however, may be mediated through the OMPR; the potency of EGPhE may be the result of bimodal inhibition of both the OMPR and AR pathways.
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Affiliation(s)
- Douglas J Fort
- Fort Environmental Laboratories, Inc., Stillwater, OK, USA
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Ziková A, Lorenz C, Hoffmann F, Kleiner W, Lutz I, Stöck M, Kloas W. Endocrine disruption by environmental gestagens in amphibians - A short review supported by new in vitro data using gonads of Xenopus laevis. CHEMOSPHERE 2017; 181:74-82. [PMID: 28431277 DOI: 10.1016/j.chemosphere.2017.04.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/02/2017] [Accepted: 04/04/2017] [Indexed: 06/07/2023]
Abstract
Endocrine disruption caused by various anthropogenic compounds is of persisting concern, especially for aquatic wildlife, because surface waters are the main sink of these so-called endocrine disruptors (ED). In the past, research focused on (anti)estrogenic, (anti)androgenic, and (anti)thyroidal substances, affecting primarily reproduction and development in vertebrates; however, other endocrine systems might be also targeted by ED. Environmental gestagens, including natural progestogens (e.g. progesterone (P4)) and synthetic progestins used for contraception, are supposed to affect vertebrate reproduction via progesterone receptors. In the present paper, we review the current knowledge about gestagenic effects in amphibians, focussing on reproduction and the thyroid system. In addition, we support the literature data with results of recent in vitro experiments, demonstrating direct impacts of the gestagens levonorgestrel (LNG) and P4 on sexually differentiated gonads of larval Xenopus laevis. The results showed a higher susceptibility of female over male gonads to gestagenic ED. Only in female gonads LNG, but not P4, had direct inhibitory effects on gene expression of steroidogenic acute regulatory protein and P450 side chain cleavage enzyme, whereas aromatase expression decreased in reaction to both gestagens. Surprisingly, beyond the expected ED effects of gestagens on reproductive physiology in amphibians, LNG drastically disrupted the thyroid system, which resembles direct effects on thyroid glands and pituitary along the pituitary-thyroid axis disturbing metamorphic development. In amphibians, environmental gestagens not only affect the reproductive system but at least LNG can impact also development by disruption of the thyroid system.
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Affiliation(s)
- Andrea Ziková
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
| | - Claudia Lorenz
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Frauke Hoffmann
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Wibke Kleiner
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Ilka Lutz
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Matthias Stöck
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Werner Kloas
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany; Department of Endocrinology, Institute of Biology, Humboldt University of Berlin, Berlin, Germany
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Shaliutina O, Shaliutina-Kolešová A, Lebeda I, Rodina M, Gazo I. The in vitro effect of nonylphenol, propranolol, and diethylstilbestrol on quality parameters and oxidative stress in sterlet (Acipenser ruthenus) spermatozoa. Toxicol In Vitro 2017; 43:9-15. [PMID: 28533019 DOI: 10.1016/j.tiv.2017.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 04/18/2017] [Accepted: 05/05/2017] [Indexed: 11/30/2022]
Abstract
The sturgeon is a highly endangered fish mostly due to over-fishing, habitat destruction, and water pollution. Nonylphenol (NP), propranolol (PN), and diethylstilbestrol (DES) are multifunctional xenobiotic compounds used in a variety of commercial and industrial products. The mechanism by which these xenobiotic compounds interfere with fish reproduction is not fully elucidated. This study assessed the effect of NP, PN, and DES on motility parameters, membrane integrity, and oxidative/antioxidant status in sterlet Acispenser ruthenus spermatozoa. Spermatozoa were incubated with several concentrations of target substances for 1h. Motility rate and velocity of spermatozoa decreased in the presence of xenobiotics in a dose-dependent manner compared with controls. A significant decrease in membrane integrity was recorded with exposure to 5μM of NP, 25μM of PN, and 50μM of DES. After 1h exposure at higher tested concentrations NP (5-25μM), PN (25-100μM), and DES (50-200μM), oxidative stress was apparent, as reflected by significantly higher levels of protein and lipid oxidation and significantly greater superoxide dismutase activity. The results demonstrated that NP, PN, and DES can induce reactive oxygen species stress in fish spermatozoa, which could impair sperm quality and the antioxidant defence system and decrease the percentage of intact sperm cells.
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Affiliation(s)
- Olena Shaliutina
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Zátiší 728/II, 389 25 Vodňany, Czech Republic.
| | - Anna Shaliutina-Kolešová
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Zátiší 728/II, 389 25 Vodňany, Czech Republic
| | - Ievgen Lebeda
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Zátiší 728/II, 389 25 Vodňany, Czech Republic
| | - Marek Rodina
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Zátiší 728/II, 389 25 Vodňany, Czech Republic
| | - Ievgeniia Gazo
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Zátiší 728/II, 389 25 Vodňany, Czech Republic
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Richter CA, Papoulias DM, Whyte JJ, Tillitt DE. Evaluation of potential mechanisms of atrazine-induced reproductive impairment in fathead minnow (Pimephales promelas) and Japanese medaka (Oryzias latipes). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:2230-2238. [PMID: 26792394 DOI: 10.1002/etc.3376] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/14/2015] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
Atrazine has been implicated in reproductive dysfunction of exposed organisms, and previous studies documented decreased egg production in Japanese medaka (Oryzias latipes) and fathead minnows (Pimephales promelas) during 30-d to 38-d exposures to 0.5 µg/L, 5 µg/L, and 50 µg/L atrazine. The authors evaluated possible mechanisms underlying the reduction in egg production. Gene expression in steroidogenesis pathways and the hypothalamus-pituitary-gonad axis of male and female fish was measured. Atrazine did not significantly induce gonad aromatase (cyp19a1a) expression. An atrazine-induced shift in the number of females in an active reproductive state was observed. Expression of the egg maturation genes vitellogenin 1 (vtg1) and zona pellucida glycoprotein 3.1 (zp3.1) in medaka females was correlated and had a bimodal distribution. In both species, females with low vtg1 or zp3.1 expression also had low expression of steroidogenesis genes in the gonad, estrogen receptor in the liver, and gonadotropins in the brain. In the medaka, the number of females per tank that had high expression of zp3.1 was significantly correlated with egg production per tank. The number of medaka females with low expression of zp3.1 increased significantly with atrazine exposure. Thus, the decline in egg production observed in response to atrazine exposure may be the result of a coordinated downregulation of genes required for reproduction in a subset of females. Environ Toxicol Chem 2016;35:2230-2238. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.
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Affiliation(s)
- Catherine A Richter
- Columbia Environmental Research Center, US Geological Survey, Columbia, Missouri
| | - Diana M Papoulias
- Columbia Environmental Research Center, US Geological Survey, Columbia, Missouri
| | - Jeffrey J Whyte
- Columbia Environmental Research Center, US Geological Survey, Columbia, Missouri
| | - Donald E Tillitt
- Columbia Environmental Research Center, US Geological Survey, Columbia, Missouri
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Kinch CD, Kurrasch DM, Habibi HR. Adverse morphological development in embryonic zebrafish exposed to environmental concentrations of contaminants individually and in mixture. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 175:286-98. [PMID: 27107150 DOI: 10.1016/j.aquatox.2016.03.021] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 03/23/2016] [Accepted: 03/28/2016] [Indexed: 05/07/2023]
Abstract
Exposure to environmental contaminants has been linked to developmental and reproductive abnormalities leading to infertility, spontaneous abortion, reduced number of offspring, and metabolic disorders. In addition, there is evidence linking environmental contaminants and endocrine disruption to abnormal developmental rate, defects in heart and eye morphology, and alterations in behavior. Notably, these effects could not be explained by interaction with a single hormone receptor. Here, using a whole-organism approach, we investigated morphological changes to developing zebrafish caused by exposure to a number of environmental contaminants, including bisphenol A (BPA), di(2-ethylhexyl)phthalate (DEHP), nonylphenol, and fucosterol at concentrations measured in a local water body (Oldman River, AB), individually and in mixture. Exposure to nanomolar contaminant concentrations resulted in abnormal morphological development, including changes to body length, pericardia (heart), and the head. We also characterize the spatiotemporal expression profiles of estrogen, androgen, and thyroid hormone receptors to demonstrate that localization of these receptors might be mediating contaminant effects on development. Finally, we examined the effects of contaminants singly and in mixture. Combined, our results support the hypothesis that adverse effects of contaminants are not mediated by single hormone receptor signaling, and adversity of contaminants in mixture could not be predicted by simple additive effect of contaminants. The findings provide a framework for better understanding of developmental toxicity of environmental contaminants in zebrafish and other vertebrate species.
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Affiliation(s)
- Cassandra D Kinch
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, Alberta, T2N 1N4, Canada; Department of Medical Genetics, Cummings School of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary, Alberta, T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Heritage Medical Research Building, 3330 Hospital Dr. NW, Calgary, Alberta, T2N 4N1, Canada.
| | - Deborah M Kurrasch
- Department of Medical Genetics, Cummings School of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary, Alberta, T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Heritage Medical Research Building, 3330 Hospital Dr. NW, Calgary, Alberta, T2N 4N1, Canada.
| | - Hamid R Habibi
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, Alberta, T2N 1N4, Canada.
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Marlatt VL, Sherrard R, Kennedy CJ, Elphick JR, Martyniuk CJ. Application of molecular endpoints in early life stage salmonid environmental biomonitoring. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 173:178-191. [PMID: 26874677 DOI: 10.1016/j.aquatox.2016.01.006] [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: 10/01/2015] [Revised: 01/16/2016] [Accepted: 01/20/2016] [Indexed: 06/05/2023]
Abstract
Molecular endpoints can enhance existing whole animal bioassays by more fully characterizing the biological impacts of aquatic pollutants. Laboratory and field studies were used to examine the utility of adopting molecular endpoints for a well-developed in situ early life stage (eyed embryo to onset of swim-up fry) salmonid bioassay to improve diagnostic assessments of water quality in the field. Coastal cutthroat trout (Oncorhynchus clarki clarki) were exposed in the laboratory to the model metal (zinc, 40μg/L) and the polycyclic aromatic hydrocarbon (pyrene, 100μg/L) in water to examine the resulting early life stage salmonid responses. In situ field exposures and bioassays were conducted in parallel to evaluate the water quality of three urban streams in British Columbia (two sites with anthropogenic inputs and one reference site). The endpoints measured in swim-up fry included survival, deformities, growth (weight and length), vitellogenin (vtg) and metallothionein (Mt) protein levels, and hepatic gene expression (e.g., metallothioneins [mta and mtb], endocrine biomarkers [vtg and estrogen receptors, esr] and xenobiotic-metabolizing enzymes [cytochrome P450 1A3, cyp1a3 and glutathione transferases, gstk]). No effects were observed in the zinc treatment, however exposure of swim-up fry to pyrene resulted in decreased survival, deformities and increased estrogen receptor alpha (er1) mRNA levels. In the field exposures, xenobiotic-metabolizing enzymes (cyp1a3, gstk) and zinc transporter (zntBigM103) mRNA were significantly increased in swim-up fry deployed at the sites with more anthropogenic inputs compared to the reference site. Cluster analysis revealed that gene expression profiles in individuals from the streams receiving anthropogenic inputs were more similar to each other than to the reference site. Collectively, the results obtained in this study suggest that molecular endpoints may be useful, and potentially more sensitive, indicators of site-specific contamination in real-world, complex exposure scenarios in addition to whole body morphometric and physiological measures.
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Affiliation(s)
- Vicki L Marlatt
- Department of Biological Sciences, Simon, Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada.
| | - Ryan Sherrard
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick, Canada
| | - Chris J Kennedy
- Department of Biological Sciences, Simon, Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada; Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick, Canada; Nautilus Environmental, 8664 Commerce Court, Imperial Square Lake City, Burnaby, British Columbia V5A 4N71, Canada
| | - James R Elphick
- Nautilus Environmental, 8664 Commerce Court, Imperial Square Lake City, Burnaby, British Columbia V5A 4N71, Canada
| | - Christopher J Martyniuk
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick, Canada
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Hagiwara A, Ogiwara K, Takahashi T. Expression of Membrane Progestin Receptors (mPRs) in Granulosa Cells of Medaka Preovulatory Follicles. Zoolog Sci 2016; 33:98-105. [DOI: 10.2108/zs150093] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Ellestad LE, Cardon M, Chambers IG, Farmer JL, Hartig P, Stevens K, Villeneuve DL, Wilson V, Orlando EF. Environmental gestagens activate fathead minnow (Pimephales promelas) nuclear progesterone and androgen receptors in vitro. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8179-8187. [PMID: 24911891 DOI: 10.1021/es501428u] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Gestagen is a collective term for endogenous and synthetic progesterone receptor (PR) ligands. In teleost fishes, 17α,20β-dihydroxy-4-pregnen-3-one (DHP) and 17α,20β,21-trihydroxy-4-pregnen-3-one (20β-S) are the predominant progestogens, whereas in other vertebrates the major progestogen is progesterone (P4). Progestins are components of human contraceptives and hormone replacement pharmaceuticals and, with P4, can enter the environment and alter fish and amphibian reproductive health. In this study, our primary objectives were to clone the fathead minnow (FHM) nuclear PR (nPR), to develop an in vitro assay for FHM nPR transactivation, and to screen eight gestagens for their ability to transactivate FHM nPR. We also investigated the ability of these gestagens to transactivate FHM androgen receptor (AR). Fish progestogens activated FHM nPR, with DHP being more potent than 20β-S. The progestin drospirenone and P4 transactivated the FHM nPR, whereas five progestins and P4 transactivated FHM AR, all at environmentally relevant concentrations. Progestins are designed to activate human PR, but older generation progestins have unwanted androgenic side effects in humans. In FHMs, several progestins proved to be strong agonists of AR. Here, we present the first mechanistic evidence that environmental gestagens can activate FHM nPR and AR, suggesting that gestagens may affect phenotype through nPR- and AR-mediated pathways.
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Affiliation(s)
- Laura E Ellestad
- Department of Animal and Avian Sciences, University of Maryland , College Park, Maryland 20742, United States
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Orlando EF, Ellestad LE. Sources, concentrations, and exposure effects of environmental gestagens on fish and other aquatic wildlife, with an emphasis on reproduction. Gen Comp Endocrinol 2014; 203:241-9. [PMID: 24759355 DOI: 10.1016/j.ygcen.2014.03.038] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 01/01/2023]
Abstract
Fish and other aquatic wildlife, including frogs, turtles, and alligators, have been used as vertebrate sentinels for the effects of endocrine disrupting and other emerging chemicals of concern found in aquatic ecosystems. Research has focused on the effects of estrogenic, androgenic, and thyroidogenic compounds, but there is a growing body of literature on the reproductive health exposure effects of environmental gestagens on aquatic wildlife. Gestagens include native progestogens, such as progesterone, and synthetic progestins, such as gestodene and levonorgestrel, which bind progesterone receptors and have critically important roles in vertebrate physiology, especially reproduction. Roles for progestogen include regulating gamete maturation and orchestrating reproductive behavior, both as circulating hormones and as secreted pheromones. Gestagens enter the aquatic environment through paper mill effluent, wastewater treatment plant effluent, and agricultural runoff. A number of gestagens have been shown to negatively affect reproduction, development, and behavior of exposed fish and other aquatic wildlife at ng/L concentrations, and these compounds have been measured in the environment at single to 375 ng/L. Given the importance of endogenous progestogens in the regulation of gametogenesis, secondary sex characteristics, and reproductive behavior in vertebrates and the documented exposure effects of pharmaceutical progestins and progesterone, environmental gestagens are an emerging class of contaminants that deserve increased attention from researchers and regulators alike. The potential for environmental gestagens to affect the reproductive health of aquatic vertebrates seems evident, but there are a number of important questions for researchers to address in this nascent field. These include identifying biomarkers of gestagen exposure; testing the effects of environmentally relevant mixtures; and determining what other physiological endpoints and taxa might be affected by exposure to environmental gestagens.
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13
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Song L, Zhao J, Jin X, Li Z, Newton IP, Liu W, Xiao H, Zhao M. The organochlorine p,p'-dichlorodiphenyltrichloroethane induces colorectal cancer growth through Wnt/β-catenin signaling. Toxicol Lett 2014; 229:284-91. [PMID: 24968063 DOI: 10.1016/j.toxlet.2014.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 05/30/2014] [Accepted: 06/01/2014] [Indexed: 01/30/2023]
Abstract
Dichlorodiphenyltrichloroethane (DDT), an organochlorine pollutant, is associated with several types of cancer. However, the relationship between DDT and colorectal cancer is uncertain. In this study, the impact of p,p'-DDT on colorectal cancer growth was evaluated using both in vitro and in vivo models. Our results indicated that the proliferation of human colorectal adenocarcinoma DLD1 cells was significantly promoted after exposed to low concentrations of p,p'-DDT ranging from 10(-12) to 10(-7) M for 96 h. Exposure to p,p'-DDT from 10(-10) to 10(-8) M led to upregulation of phospho-GSK3β (Ser9), β-catenin, c-Myc and cyclin D1 in DLD1 cells. RNA interference of β-catenin inhibited the proliferation of DLD1 cells stimulated by p,p'-DDT. Inhibiting of estrogen receptors (ERs) had no significant effect on the action of p,p'-DDT. Treatment with p,p'-DDT induced production of intracellular reactive oxygen species (ROS) and inhibited superoxide dismutase (SOD) activity in DLD1 cells. Treatment with N-acetyl-L-cysteine (NAC), a ROS inhibitor, suppressed the induction of Wnt/β-catenin signaling and DLD1 cell proliferation by p,p'-DDT. Moreover, in a mouse xenograft model, 5 nmol/kg p,p'-DDT resulted in increased tumor size, oxidative stress and Wnt/β-catenin signaling. These results indicated that low concentrations of p,p'-DDT promoted colorectal cancer growth through Wnt/β-catenin signaling, which was mediated by oxidative stress. The finding suggests an association between low concentrations of p,p'-DDT exposure and colorectal cancer progression.
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Affiliation(s)
- Li Song
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China; MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Junyu Zhao
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China
| | - Xiaoting Jin
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China
| | - Zhuoyu Li
- Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China; College of Life Science, Zhejiang Chinese Medical University, Hangzhou 310053, China.
| | - Ian P Newton
- Division of Cell & Developmental Biology, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Weiping Liu
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hong Xiao
- Department of Parthology, The First Affiliated Hospital, Shanxi Medical University, Taiyuan 030001, China
| | - Meirong Zhao
- Research Center of Environmental Science, Zhejiang University of Technology, Hangzhou 310032, China.
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14
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Tan W, Aizen J, Thomas P. Membrane progestin receptor alpha mediates progestin-induced sperm hypermotility and increased fertilization success in southern flounder (Paralichthys lethostigma). Gen Comp Endocrinol 2014; 200:18-26. [PMID: 24530629 DOI: 10.1016/j.ygcen.2014.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/21/2014] [Accepted: 02/03/2014] [Indexed: 01/22/2023]
Abstract
Progestin hormones stimulate sperm motility in teleosts but their mechanisms of action remain unclear. Preliminary results suggest that progestin upregulation of sperm motility in southern flounder and several other marine species is mediated through a sperm membrane progestin receptor with the characteristics of membrane progestin receptor alpha (mPRα, also known as Paqr7b). The hypothesis that mPRα has an important role in progestin regulation of southern flounder sperm motility and fertility was tested in the present study. The specific mPRα agonist, 10-ethenyl-19-norprogesterone (Org OD 02-0, 100nM), mimicked the stimulatory actions of the endogenous progestin, 17,20β, 21-trihydroxy-4-pregnen-3-one (20β-S, 100nM) on flounder sperm motility. The concentration of the mPRα protein on sperm plasma membranes was positively correlated to sperm motility as well as the responsiveness of sperm to progestin stimulation. Acute in vitro progestin treatment of sperm with high mPRα protein levels increased both sperm motility and fertilization success in strip spawning experiments. However, in vitro progestin treatments were ineffective on sperm with low receptor abundance. A single injection of the superactive gonadotropin-releasing hormone analog (LHRHa, 100μg/kg) increased sperm motility and fertilization success in strip spawning experiments 72h post-injection which was accompanied by an increase in mPRα protein concentrations on sperm plasma membranes. These results provide clear evidence that southern flounder sperm hypermotility is mediated through mPRα. Stimulatory G proteins, but not inhibitory G proteins, were identified in flounder sperm plasma membrane fractions. The finding that treatment of flounder sperm plasma membrane fractions with either 20β-S or Org OD 02-0 increases cAMP levels suggests progestins stimulate flounder sperm motility by activating an mPRα/stimulatory G protein/membrane adenylyl cyclase pathway. A similar mechanism has been identified in Atlantic croaker, suggesting that the signaling pathway mediated by mPRα in sperm is highly conserved in advanced teleosts. Collectively, our results indicate that progestin-stimulation of flounder sperm hypermotility and fertility is dependent on a sufficient concentration of mPRα which can be upregulated by in vivo LHRHa treatments. These findings potentially have practical applications for enhancing the fertility of male flounder broodstock.
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Affiliation(s)
- Wenxian Tan
- The University of Texas at Austin, Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA
| | - Joseph Aizen
- The University of Texas at Austin, Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA
| | - Peter Thomas
- The University of Texas at Austin, Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
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15
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Segner H, Casanova-Nakayama A, Kase R, Tyler CR. Impact of environmental estrogens on Yfish considering the diversity of estrogen signaling. Gen Comp Endocrinol 2013; 191:190-201. [PMID: 23763869 DOI: 10.1016/j.ygcen.2013.05.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2012] [Revised: 05/16/2013] [Accepted: 05/29/2013] [Indexed: 12/31/2022]
Abstract
Research on endocrine disruption in fish has been dominated by studies on estrogen-active compounds which act as mimics of the natural estrogen, 17β-estradiol (E2), and generally exert their biological actions by binding to and activation of estrogen receptors (ERs). Estrogens play central roles in reproductive physiology and regulate (female) sexual differentiation. In line with this, most adverse effects reported for fish exposed to environmental estrogens relate to sexual differentiation and reproduction. E2, however, utilizes a variety of signaling mechanisms, has multifaceted functions and targets, and therefore the toxicological and ecological effects of environmental estrogens in fish will extend beyond those associated with the reproduction. This review first describes the diversity of estrogen receptor signaling in fish, including both genomic and non-genomic mechanisms, and receptor crosstalk. It then considers the range of non-reproductive physiological processes in fish that are known to be responsive to estrogens, including sensory systems, the brain, the immune system, growth, specifically through the growth hormone/insulin-like growth factor system, and osmoregulation. The diversity in estrogen responses between fish species is then addressed, framed within evolutionary and ecological contexts, and we make assessments on their relevance for toxicological sensitivity as well as ecological vulnerability. The diversity of estrogen actions raises questions whether current risk assessment strategies, which focus on reproductive endpoints, and a few model fish species only, are protective of the wider potential health effects of estrogens. Available - although limited - evidence nevertheless suggests that quantitative environmental threshold concentrations for environmental protection derived from reproductive tests with model fish species are protective for non-reproductive effects as well. The diversity of actions of estrogens across divergent physiological systems, however, may lead to and underestimation of impacts on fish populations as their effects are generally considered on one functional process only and this may underrepresent the impact on the different physiological processes collectively.
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Affiliation(s)
- Helmut Segner
- Centre for Fish and Wildlife Health, University of Bern, Bern, Switzerland.
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16
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A systematic review of Bisphenol A "low dose" studies in the context of human exposure: a case for establishing standards for reporting "low-dose" effects of chemicals. Food Chem Toxicol 2013; 62:935-48. [PMID: 23867546 DOI: 10.1016/j.fct.2013.07.007] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 06/17/2013] [Accepted: 07/01/2013] [Indexed: 12/30/2022]
Abstract
Human exposure to the chemical Bisphenol A is almost ubiquitous in surveyed industrialized societies. Structural features similar to estrogen confer the ability of Bisphenol A (BPA) to bind estrogen receptors, giving BPA membership in the group of environmental pollutants called endocrine disruptors. References by scientists, the media, political entities, and non-governmental organizations to many toxicity studies as "low dose" has led to the belief that exposure levels in these studies are similar to humans, implying that BPA is toxic to humans at current exposures. Through systematic, objective comparison of our current, and a previous compilation of the "low-dose" literature to multiple estimates of human external and internal exposure levels, we found that the "low-dose" moniker describes exposures covering 8-12 orders of magnitude, the majority (91-99% of exposures) being greater than the upper bound of human exposure in the general infant, child and adult U.S. Population. "low dose" is therefore a descriptor without specific meaning regarding human exposure. Where human exposure data are available, for BPA and other environmental chemicals, reference to toxicity study exposures by direct comparison to human exposure would be more informative, more objective, and less susceptible to misunderstanding.
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17
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Gazo I, Linhartova P, Shaliutina A, Hulak M. Influence of environmentally relevant concentrations of vinclozolin on quality, DNA integrity, and antioxidant responses of sterlet Acipenser ruthenus spermatozoa. Chem Biol Interact 2013; 203:377-85. [PMID: 23376258 DOI: 10.1016/j.cbi.2013.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 12/12/2012] [Accepted: 01/21/2013] [Indexed: 12/29/2022]
Abstract
The effects of vinclozolin (VIN), an anti-androgenic fungicide, on quality, oxidative stress, DNA integrity, and ATP level of sterlet (Acipenser ruthenus) spermatozoa were investigated in vitro. Fish spermatozoa were incubated with different concentrations of vinclozolin (0.5, 2, 10, 15, 20 and 50 μg/l) for 2 h. A dose-dependent reduction in spermatozoa motility and velocity was observed at concentrations of 2-50 μg/l. A dramatic increase in DNA fragmentation was recorded at concentrations 10 μg/l and above. After 2 h exposure at higher test concentrations (10-50 μg/l), oxidative stress was apparent, as reflected by significantly higher levels of protein and lipid oxidation and significantly greater superoxide dismutase activity. Intracellular ATP content of spermatozoa decreased with increasing concentrations of VIN. The results demonstrated that VIN can induce reactive oxygen species stress in fish spermatozoa, which could impair the sperm quality, DNA integrity, ATP content, and the antioxidant defense system.
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Affiliation(s)
- Ievgeniia Gazo
- Faculty of Fisheries and Protection of Waters, Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia, Zatisi 728/11, Vodnany 32901, Czech Republic.
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18
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Thomas P. Rapid steroid hormone actions initiated at the cell surface and the receptors that mediate them with an emphasis on recent progress in fish models. Gen Comp Endocrinol 2012; 175:367-83. [PMID: 22154643 PMCID: PMC3264783 DOI: 10.1016/j.ygcen.2011.11.032] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 11/17/2011] [Accepted: 11/18/2011] [Indexed: 02/06/2023]
Abstract
In addition to the classic genomic mechanism of steroid action mediated by activation of intracellular nuclear receptors, there is now extensive evidence that steroids also activate receptors on the cell surface to initiate rapid intracellular signaling and biological responses that are often nongenomic. Recent progress in our understanding of rapid, cell surface-initiated actions of estrogens, progestins, androgens and corticosteroids and the identities of the membrane receptors that act as their intermediaries is briefly reviewed with a special emphasis on studies in teleost fish. Two recently discovered novel proteins with seven-transmembrane domains, G protein-coupled receptor 30 (GPR30), and membrane progestin receptors (mPRs) have the ligand binding and signaling characteristics of estrogen and progestin membrane receptors, respectively, but their functional significance is disputed by some researchers. GPR30 is expressed on the cell surface of fish oocytes and mediates estrogen inhibition of oocyte maturation. mPRα is also expressed on the oocyte cell surface and is the intermediary in progestin induction of oocyte maturation in fish. Recent results suggest there is cross-talk between these two hormonal pathways and that there is reciprocal down-regulation of GPR30 and mPRα expression by estrogens and progestins at different phases of oocyte development to regulate the onset of oocyte maturation. There is also evidence in fish that mPRs are involved in progestin induction of sperm hypermotility and anti-apoptotic actions in ovarian follicle cells. Nonclassical androgen and corticosteroid actions have also been described in fish models but the membrane receptors mediating these actions have not been identified.
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Affiliation(s)
- Peter Thomas
- The University of Texas at Austin, Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
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19
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Tubbs C, Tan W, Shi B, Thomas P. Identification of 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S) receptor binding and membrane progestin receptor alpha on southern flounder sperm (Paralichthys lethostigma) and their likely role in 20β-S stimulation of sperm hypermotility. Gen Comp Endocrinol 2011; 170:629-39. [PMID: 21163260 DOI: 10.1016/j.ygcen.2010.12.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 12/02/2010] [Accepted: 12/05/2010] [Indexed: 11/30/2022]
Abstract
The existence of direct progestin actions on teleost sperm to stimulate hypermotility is not widely acknowledged because it has only been demonstrated in members of the family Sciaenidae. In the present study, progestin stimulation of sperm hypermotility was investigated in a non-sciaenid, southern flounder, and the potential role of membrane progestin receptor alpha (mPRα or Paqr7b) in mediating this action was examined. The major progestin produced in vitro by flounder testicular fragments co-migrated with 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S) during thin-layer chromatography. Treatment of flounder sperm with 5 nM-100 nM 20β-S significantly increased sperm velocity in vitro, whereas 17,20β-dihydroxy-4-pregnen-3-one and other steroids were ineffective. A single class of high affinity (K(d) 22.95 nM), saturable, limited-capacity binding sites (B(max) 0.013 nM) specific for 20β-S was identified on sperm membranes. Treatment of sperm membranes with guanosine 5'-(3-O-thio)triphosphate reduced [(3)H]-20β-S binding, suggesting the 20β-S receptor couples to a G protein. The membrane adenylyl cyclase inhibitor 2',5'-dideoxyadenosine blocked 20β-S-induced sperm hypermotility, indicating 20β-S activates stimulatory G proteins. Finally, flounder paqr7b was cloned and characterized from testicular tissues. The Paqr7b protein is expressed on the midpiece of flounder sperm and is more abundant in individuals with high sperm motility than low motility donors. These findings suggest that 20β-S stimulates sperm hypermotility in flounder through activation of stimulatory G proteins, likely through Paqr7b. The finding that progestins directly stimulate sperm hypermotility in a flatfish, a highly derived species not belonging to the teleost family Sciaenidae, suggests this phenomenon is widespread among advanced fishes.
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Affiliation(s)
- Christopher Tubbs
- The University of Texas at Austin, Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
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20
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Tillitt DE, Papoulias DM, Whyte JJ, Richter CA. Atrazine reduces reproduction in fathead minnow (Pimephales promelas). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 99:149-159. [PMID: 20471700 DOI: 10.1016/j.aquatox.2010.04.011] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Revised: 03/31/2010] [Accepted: 04/13/2010] [Indexed: 05/28/2023]
Abstract
Atrazine, the widely used herbicide, has shown to affect the hypothalamus-pituitary-gonad axis in certain vertebrate species, but few studies have examined reproductive effects of this chemical on fish. Our study was designed to evaluate a population endpoint (egg production) in conjunction with histological (e.g., gonad development) and biochemical (e.g., hormone production) phenotypes associated with atrazine exposure in fathead minnows. Adult virgin breeding groups of 1 male and 2 females were exposed to nominal concentrations of 0, 0.5, 5.0, and 50 microg/L of atrazine in a flow-through diluter for 14 or 30 days. Total egg production was lower (19-39%) in all atrazine-exposed groups as compared to the controls. The decreases in cumulative egg production of atrazine treated fish were significant by 17-20 days of exposure. Reductions in egg production in atrazine treatment groups were most attributable to reduced numbers of spawning events with increased atrazine exposure concentrations. Gonad abnormalities were observed in both male and female fish of atrazine-exposed fish. Our results also indicate that atrazine reduces egg production through alteration of final maturation of oocytes. The reproductive effects observed in this study warrant further investigation and evaluation of the potential risks posed by atrazine, particularly feral populations of fish from streams in agricultural areas with high use of this herbicide.
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Affiliation(s)
- Donald E Tillitt
- Columbia Environmental Research Center, U.S. Geological Survey, 4200 New Haven Road, Columbia, MO 65201, USA.
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21
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Tubbs C, Pace M, Thomas P. Expression and gonadotropin regulation of membrane progestin receptor alpha in Atlantic croaker (Micropogonias undulatus) gonads: role in gamete maturation. Gen Comp Endocrinol 2010; 165:144-54. [PMID: 19539624 DOI: 10.1016/j.ygcen.2009.06.017] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 05/28/2009] [Accepted: 06/12/2009] [Indexed: 11/15/2022]
Abstract
Recent results suggest that membrane progestin receptor alpha (mPRalpha) mediates nongenomic actions of progestin hormones to induce oocyte maturation and sperm hypermotility in several teleost species. The role of mPRalpha in gamete and gonadal physiology was further evaluated in the present study by examining gonadal expression of mPRalpha during gamete maturation in Atlantic croaker (Micropogonias undulatus), a well-characterized teleost model of oocyte maturation and sperm motility. Sequencing of the croaker mPRalpha gene isolated from croaker ovaries showed it is 98% homologous at the nucleotide level to spotted seatrout mPRalpha. The mPRalpha mRNA and protein were detected in both somatic and gonadal tissues. In croaker ovaries, the mPRalpha protein was present throughout the gonadal cycle and was upregulated by gonadotropin in vitro, coincident with the acquisition of oocyte maturational competence (i.e., ability to respond to progestin hormones and complete oocyte maturation). Both mPRalpha mRNA and protein were also expressed in croaker testes throughout the gonadal cycle. Expression of mPRalpha protein was weakly upregulated in testes after 18 h of in vitro gonadotropin treatment. Immunocytochemical staining showed mPRalpha was localized to both germ and interstitial cells. Finally, elevated levels of mPRalpha protein in croaker sperm were associated with high sperm motility. Taken together, these data strongly support the hypothesis that mPRalpha mediates progestin induction of oocyte maturation and upregulation of sperm motility in teleosts.
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Affiliation(s)
- Christopher Tubbs
- The University of Texas at Austin, Marine Science Institute, Port Aransas, 78373 TX, USA
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22
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Watson CS, Jeng YJ, Kochukov MY. Nongenomic signaling pathways of estrogen toxicity. Toxicol Sci 2009; 115:1-11. [PMID: 19955490 DOI: 10.1093/toxsci/kfp288] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Xenoestrogens can affect the healthy functioning of a variety of tissues by acting as potent estrogens via nongenomic signaling pathways or by interfering with those actions of multiple physiological estrogens. Collectively, our and other studies have compared a wide range of estrogenic compounds, including some closely structurally related subgroups. The estrogens that have been studied include environmental contaminants of different subclasses, dietary estrogens, and several prominent physiological metabolites. By comparing the nongenomic signaling and functional responses to these compounds, we have begun to address the structural requirements for their actions through membrane estrogen receptors in the pituitary, in comparison to other tissues, and to gain insights into their typical non-monotonic dose-response behavior. Their multiple inputs into cellular signaling begin processes that eventually integrate at the level of mitogen-activated protein kinase activities to coordinately regulate broad cellular destinies, such as proliferation, apoptosis, or differentiation.
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Affiliation(s)
- Cheryl S Watson
- Biochemistry & Molecular Biology Department, University of Texas Medical Branch, Galveston, Texas 77555-0645, USA.
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23
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Garcia-Reyero N, Kroll KJ, Liu L, Orlando EF, Watanabe KH, Sepúlveda MS, Villeneuve DL, Perkins EJ, Ankley GT, Denslow ND. Gene expression responses in male fathead minnows exposed to binary mixtures of an estrogen and antiestrogen. BMC Genomics 2009; 10:308. [PMID: 19594897 PMCID: PMC2713996 DOI: 10.1186/1471-2164-10-308] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Accepted: 07/13/2009] [Indexed: 12/31/2022] Open
Abstract
Background Aquatic organisms are continuously exposed to complex mixtures of chemicals, many of which can interfere with their endocrine system, resulting in impaired reproduction, development or survival, among others. In order to analyze the effects and mechanisms of action of estrogen/anti-estrogen mixtures, we exposed male fathead minnows (Pimephales promelas) for 48 hours via the water to 2, 5, 10, and 50 ng 17α-ethinylestradiol (EE2)/L, 100 ng ZM 189,154/L (a potent antiestrogen known to block activity of estrogen receptors) or mixtures of 5 or 50 ng EE2/L with 100 ng ZM 189,154/L. We analyzed gene expression changes in the gonad, as well as hormone and vitellogenin plasma levels. Results Steroidogenesis was down-regulated by EE2 as reflected by the reduced plasma levels of testosterone in the exposed fish and down-regulation of genes in the steroidogenic pathway. Microarray analysis of testis of fathead minnows treated with 5 ng EE2/L or with the mixture of 5 ng EE2/L and 100 ng ZM 189,154/L indicated that some of the genes whose expression was changed by EE2 were blocked by ZM 189,154, while others were either not blocked or enhanced by the mixture, generating two distinct expression patterns. Gene ontology and pathway analysis programs were used to determine categories of genes for each expression pattern. Conclusion Our results suggest that response to estrogens occurs via multiple mechanisms, including canonical binding to soluble estrogen receptors, membrane estrogen receptors, and other mechanisms that are not blocked by pure antiestrogens.
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Affiliation(s)
- Natàlia Garcia-Reyero
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.
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Diamanti-Kandarakis E, Bourguignon JP, Giudice LC, Hauser R, Prins GS, Soto AM, Zoeller RT, Gore AC. Endocrine-disrupting chemicals: an Endocrine Society scientific statement. Endocr Rev 2009; 30:293-342. [PMID: 19502515 PMCID: PMC2726844 DOI: 10.1210/er.2009-0002] [Citation(s) in RCA: 2694] [Impact Index Per Article: 179.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 04/17/2009] [Indexed: 12/11/2022]
Abstract
There is growing interest in the possible health threat posed by endocrine-disrupting chemicals (EDCs), which are substances in our environment, food, and consumer products that interfere with hormone biosynthesis, metabolism, or action resulting in a deviation from normal homeostatic control or reproduction. In this first Scientific Statement of The Endocrine Society, we present the evidence that endocrine disruptors have effects on male and female reproduction, breast development and cancer, prostate cancer, neuroendocrinology, thyroid, metabolism and obesity, and cardiovascular endocrinology. Results from animal models, human clinical observations, and epidemiological studies converge to implicate EDCs as a significant concern to public health. The mechanisms of EDCs involve divergent pathways including (but not limited to) estrogenic, antiandrogenic, thyroid, peroxisome proliferator-activated receptor gamma, retinoid, and actions through other nuclear receptors; steroidogenic enzymes; neurotransmitter receptors and systems; and many other pathways that are highly conserved in wildlife and humans, and which can be modeled in laboratory in vitro and in vivo models. Furthermore, EDCs represent a broad class of molecules such as organochlorinated pesticides and industrial chemicals, plastics and plasticizers, fuels, and many other chemicals that are present in the environment or are in widespread use. We make a number of recommendations to increase understanding of effects of EDCs, including enhancing increased basic and clinical research, invoking the precautionary principle, and advocating involvement of individual and scientific society stakeholders in communicating and implementing changes in public policy and awareness.
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Affiliation(s)
- Evanthia Diamanti-Kandarakis
- Endocrine Section of First Department of Medicine, Laiko Hospital, Medical School University of Athens, 11527 Athens, Greece
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Thomas P, Rahman MS. Chronic hypoxia impairs gamete maturation in Atlantic croaker induced by progestins through nongenomic mechanisms resulting in reduced reproductive success. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:4175-4180. [PMID: 19569348 DOI: 10.1021/es9000399] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Recent studies have shown that chronic hypoxia exposure impairs reproduction in fish by interfering with endocrine function, although the mechanisms of endocrine disruption remain unclear. The effects of chronic exposure (4 or 10 weeks) to hypoxia (dissolved oxygen, DO: 1.7 mg L(-1)) on gamete maturation and its endocrine control, as well as the consequences for reproductive success, were investigated in Atlantic croaker (Micropogonias undulatus). Circulating levels of the progestin hormone that induces gamete maturation, 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S), were significantly decreased in croaker of both sexes chronically exposed to hypoxia and were associated with impairment of oocyte meiotic maturation and sperm motility. Interestingly, expression of the novel membrane receptor mediating these nongenomic 20beta-S actions, membrane progestin receptor alpha (mPRalpha), was significantly decreased on oocyte and sperm plasma membranes of hypoxia-exposed fish. Hypoxia-induced impairment of gamete maturation was accompanied with a dramatic decline in the percent fertilized eggs in a spawning trial. Moreover, the fertilized eggs from hypoxia-exposed donors displayed decreased hatching success and larval survival. The results suggestthat nongenomic progestin signaling controlling the final stages of the reproductive cycle in fish is impaired under hypoxic conditions.
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Affiliation(s)
- Peter Thomas
- University of Texas at Austin, Marine Science Institute, 750 Channel View Drive, Port Aransas, Texas 78373, USA.
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Sawasdee B, Köhler HR. Embryo toxicity of pesticides and heavy metals to the ramshorn snail, Marisa cornuarietis (Prosobranchia). CHEMOSPHERE 2009; 75:1539-1547. [PMID: 19278713 DOI: 10.1016/j.chemosphere.2009.01.085] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 01/23/2009] [Accepted: 01/29/2009] [Indexed: 05/27/2023]
Abstract
An invertebrate embryo toxicity test with the ampullariid snail, Marisacornuarietis, to assess the toxicity of pesticides and heavy metals recently was established. Snail embryos were treated with atrazine (100, 1000, 10000, and 30000 microg/L), imidacloprid (10000, 25000, and 50000 microg/L), Ni(2+) (0.1, 1, 10, and 100 microg/L) or Zn(2+) (100, 200, 500, 1000, 2000, and 5000 microg/L). The effect of these substances was examined by monitoring the following endpoints: mortality, formation of tentacles and eyes, heart rate, hatching, and weight after hatching. Effects in term of a significant delay on the formation of both tentacles and eyes were found after treatment with 100 microg/L Ni(2+) or 200 microg/L Zn(2+). The heart rate was shown to significantly decrease at 25000 microg/L imidacloprid or 1000 microg/L Zn(2+). At 100 microg/L atrazine, 10 microg/L Ni(2+), or 1000 microg/L Zn(2+) a significant delay in hatching became visible. No significant mortality was observed for the tested concentrations of atrazine, imidacloprid, or Ni(2+), while 5000 microg/L Zn(2+) resulted in 100% mortality after 10d. The weight of freshly hatched individuals remained unaffected in all treatments. On the basis of the lowest observed effect concentrations (LOECs) recorded, we could show the M.cornuarietis embryo toxicity test (MariETT) to react up to three orders of magnitude more sensitive (for metals) and at least one order of magnitude more sensitive (for the tested organics) than the established Danio rerio embryo test.
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Affiliation(s)
- Banthita Sawasdee
- Animal Physiological Ecology, University of Tübingen, Konrad-Adenauer-Strasse 20, D-72072 Tübingen, Germany.
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Tubbs C, Thomas P. Progestin signaling through an olfactory G protein and membrane progestin receptor-alpha in Atlantic croaker sperm: potential role in induction of sperm hypermotility. Endocrinology 2009; 150:473-84. [PMID: 18801904 DOI: 10.1210/en.2008-0512] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Progestin stimulation of sperm hypermotility remains poorly understood despite having been described in numerous vertebrate species. We show here that progestin stimulation of sperm hypermotility in a teleost, the Atlantic croaker (Micropogonias undulatus) is associated with activation of an olfactory G protein (Golf). Furthermore, we provide evidence that this progestin action is mediated by membrane progestin receptor-alpha (mPRalpha). Golf was identified in croaker sperm membranes and was specifically activated after treatment with the progestin 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S). Treatment of sperm membranes with 20beta-S caused an increase in cAMP production, which was blocked by pretreatment with cholera toxin and two membrane adenylyl cyclase inhibitors: 2',5'-dideoxyadenosine and SQ22536. Moreover, preincubation of croaker sperm with 2',5'-dideoxyadenosine and SQ22536 resulted in a significant inhibition of 20beta-S-stimulated hypermotility. Binding of [3H]20beta-S to sperm membranes was decreased after pretreatment with GTPgammaS but not pertussis toxin, suggesting the receptor is coupled to a pertussis toxin-insensitive G protein. Golf and mPRalpha were coexpressed on the sperm midpiece and flagella and were coimmunoprecipitated from sperm membranes. Finally, expression of mPRalpha protein on sperm increased after in vivo treatment with LHRH and was associated with increased induction of sperm motility by 20beta-S. These results suggest that 20beta-S activates mPRalpha in croaker sperm, which in turn activates Golf and membrane adenylyl cyclase to stimulate sperm hypermotility. Taken together these findings provide a plausible mechanism by which progestins stimulate sperm hypermotility in croaker and provide the first evidence of hormonal activation of Golf in any species.
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Affiliation(s)
- Christopher Tubbs
- Marine Science Institute, The University of Texas at Austin, Port Aransas, Texas 78373, USA.
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Yan W, Zhao L, Feng Q, Lin JM. Determination of estrogens and their metabolites in water using C30SPE-LC-MS. J Sep Sci 2008; 31:3581-7. [DOI: 10.1002/jssc.200800236] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Thomas P, Sweatman J. Interference by atrazine and bisphenol-A with progestin binding to the ovarian progestin membrane receptor and induction of oocyte maturation in Atlantic croaker. MARINE ENVIRONMENTAL RESEARCH 2008; 66:1-2. [PMID: 18378294 DOI: 10.1016/j.marenvres.2008.02.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Recent studies have shown that several environmental chemicals which disrupt classical genomic steroid actions can also interfere with nongenomic steroid actions initiated at the cell surface. The effects of bisphenol-A and atrazine on the nongenomic actions of a progestin, 17,20 beta,21-trihydroxy-4-pregnen-3-one (20 beta-S), on oocyte maturation (OM) were investigated an in vitro Atlantic croaker (Micropogonias undulatus) oocyte bioassay. Treatment of croaker follicle-enclosed oocytes with either bisphenol-A or atrazine blocked OM in response to 20 beta-S in a concentration-dependent manner at 10-25 microM (2.2-5.7 ppm) and higher concentrations. These compounds were also effective competitors at concentrations of 10(-6)-10(-5)M of [3H]-20 beta-S binding to the ovarian progestin membrane receptor that mediates the OM response to 20 beta-S. The results suggest that diverse classes of environmental chemicals can disrupt nongenomic progestin actions via receptor-mediated mechanisms.
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Affiliation(s)
- Peter Thomas
- University of Texas at Austin, Marine Science Institute, Port Aransas, TX 78373, USA.
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Kim SB, Kanno A, Ozawa T, Tao H, Umezawa Y. Nongenomic activity of ligands in the association of androgen receptor with SRC. ACS Chem Biol 2007; 2:484-92. [PMID: 17602621 DOI: 10.1021/cb7000439] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Androgen receptor (AR) induces cell proliferation by increasing the kinase activity of Src. We describe an approach for discriminating agonist and antagonist in a nongenomic steroid-signaling pathway using an association of AR with Src. We constructed a pair of genetically encoded indicators, where N- and C-terminal fragments of split firefly luciferase (FLuc) were fused to AR and Src, respectively. The fusion proteins with AR and Src are localized in the cytoplasm and on the plasma membrane, respectively. Upon being activated with androgen, AR undergoes an intramolecular conformational change and binds with Src. The association causes the complementation of the split FLuc and recovery of FLuc activity. The resulting luminescence intensities were taken as a measure of the rapid hormonal activity of steroids in the nongenomic AR signaling. Ten minutes are required for the AR-Src association by 5alpha-dihydroxytestosterone (DHT), which was completely inhibited by an antagonist, cyproterone acetate. The activities of ligands in the nongenomic pathway of AR were compared with those in the genomic pathway obtained on the basis of the nuclear trafficking of AR in mammalian cells. The comparison revealed that DHT and testosterone activate both genomic and nongenomic pathways of AR. 17beta-Estradiol and progesterone were found to be specific activators only for the genomic signaling pathway of AR. On the other hand, procymidone exhibited a specific activity only for the nongenomic signaling pathway of AR. The present approach is the first example addressing the agonistic and antagonistic activities of ligands in a nongenomic pathway of AR.
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Affiliation(s)
- Sung Bae Kim
- Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology, Onogawa, Tsukuba, Japan
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Ropero AB, Alonso-Magdalena P, Ripoll C, Fuentes E, Nadal A. Rapid endocrine disruption: environmental estrogen actions triggered outside the nucleus. J Steroid Biochem Mol Biol 2006; 102:163-9. [PMID: 17084624 DOI: 10.1016/j.jsbmb.2006.09.019] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An exogenous substance is defined as an endocrine disrupter chemical (EDC) if it alters the function of the endocrine system provoking adverse health effects. Environmental estrogens are the most studied EDCs. They follow the same mechanisms of action as the gonadal hormone 17beta-estradiol. Up to now, the estrogenicity of environmental estrogenic pollutants has been based on the property of these compounds to bind to estrogen receptors (ERs), either ERalpha or ERbeta, and to act subsequently as transcription factors when binding to the estrogen response element (ERE) in the DNA. All the estrogenic bioassays currently used are based on this mechanism of action. New evidence indicates that the definition of estrogenicity for a chemical should take into account other estrogen receptors as well as new signaling pathways. These include the activation of additional transcription factors as well as the action of xenoestrogens through estrogen receptors located outside the nucleus: in the plasma membrane, mitochondria and probably the cytosol. Therefore, new estrogenic bioassays should be developed to include the novel concept of rapid endocrine disruption.
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Affiliation(s)
- Ana B Ropero
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, 03202 Elche, Alicante, Spain
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Wu Y, Foster WG, Younglai EV. Rapid effects of pesticides on human granulosa-lutein cells. Reproduction 2006; 131:299-310. [PMID: 16452723 DOI: 10.1530/rep.1.00922] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Following our previous demonstration that p,p'-DDE (dichlorodiphenylchloroethylene), at environmentally relevant concentrations, can rapidly increase intracellular calcium [Ca2+]i concentrations in human granulosa-lutein cells, we examined whether other pesticides, such as Kepone, o,p-DDE and methoxychlor, have similar effects. Cultured human granulosa-lutein cells were loaded with Fura-2 AM, and changes in [Ca2+]i concentrations within small areas of single cells were studied with a dynamic digital Ca2+ imaging system. Kepone, at concentrations of 0.2-2 nmol/ml, consistently increased [Ca2+]i concentrations 2-6 times higher than baseline values within minutes of exposure. Methoxychlor at concentrations of 2.8-280 nmol/ml failed to alter [Ca2+]i levels consistently in cells from 10 patients. However, at 0.28 and 1.4 nmol/ml, increases in [Ca2+]i concentrations could be elicited by methoxychlor. The isomer o,p-DDE at 3 nmol/ml increased [Ca2+]i in granulosa cells of 11/20 patients. Pertussis toxin treatment inhibited the [Ca2+]i increases induced by estradiol, p,p'-DDE, o,p-DDE and methoxychlor, but not by Kepone or progesterone, indicating that Kepone and progesterone may act through an insensitive G protein-coupled receptor. The [Ca2+]i increases induced by Kepone also occurred in Ca2+-free medium, suggesting that [Ca2+]i mobilization occurred from the smooth endoplasmic reticulum. Thapsigargin and cyclopiazonic acid, two inhibitors of the endoplasmic reticulum Ca2+ pump, also stimulated [Ca2+]i increases but did not inhibit the Ca2+ response to all the pesticides. These results demonstrate that pesticides can have a rapid effect on human granulosa-lutein cells, and a nongenomic mechanism of action is suggested.
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Affiliation(s)
- Yanjing Wu
- Department of Obstetrics and Gynecology, Reproductive Biology Division, McMaster University, Health Sciences Centre, 1200 Main Street West, Hamilton, Ontario, Canada, L8N 3Z5
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Mastrangelo S, Tomassetti M, Carratù MR, Evandri MG, Bolle P. Quercetin reduces chromosome aberrations induced by atrazine in the Allium cepa test. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2006; 47:254-9. [PMID: 16416428 DOI: 10.1002/em.20199] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Quercetin is a widely distributed plant flavonoid possessing a variety of chemical and biological activities, including chelation, free-radical scavenging, and antioxidant activity. Atrazine is a selective triazine herbicide that has been the subject of an international revision program for human and ecological health risks because of its persistence in the environment. In a previous study, we demonstrated that atrazine was clastogenic in the Allium cepa test. In this present study, we investigated whether quercetin affords protection from the chromosome breaks induced by atrazine. In a preliminary assay, 0.1-20 microg/ml quercetin produced no toxicity or clastogenic activity in the Allium cepa test. Subsequently, we evaluated the effects of 0.5 and 5 microg/ml quercetin on the clastogenicity of 2.5, 5.0, and 7.5 microg/l atrazine. Quercetin (0.5 microg/ml) significantly reduced the frequency of total aberrations induced by 7.5 microg/l atrazine, while both concentrations of quercetin significantly decreased the frequency of fragments induced by 7.5 microg/l atrazine. The results of this study indicate that plant flavonoids such as quercetin may protect against the genotoxic effects of atrazine. Efforts to understand the extent to which plant flavonoids influence the biological activities of genotoxicants and the mechanisms involved in the interactions could help to better discern the advantages and disadvantages of their use and to clarify their possible protective role against pollutants.
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Affiliation(s)
- Sabina Mastrangelo
- Department of Pharmacology and Human Physiology, University of Bari, Italy
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Thomas P, Dressing G, Pang Y, Berg H, Tubbs C, Benninghoff A, Doughty K. Progestin, estrogen and androgen G-protein coupled receptors in fish gonads. Steroids 2006; 71:310-6. [PMID: 16289637 DOI: 10.1016/j.steroids.2005.09.015] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The identities of the membrane receptors mediating the majority of rapid, cell surface-initiated, nongenomic (i.e. nonclassical) steroid actions described to date are unclear. Two novel 7-transmembrane spanning proteins, representing two distinct classes of steroid membrane receptors, membrane progestin receptor alpha (mPRalpha) and a membrane estrogen receptor (mER), GPR30, have recently been identified in several vertebrate species. Evidence that both receptors activate G-proteins and function as G-protein coupled receptors (GPCRs) is briefly reviewed. New data on progestin actions on fish gametes suggest a widespread involvement of mPRalpha in oocyte maturation and sperm hyperactivity in this vertebrate group. Information on the second messenger pathways activated upon estrogen binding to a membrane estrogen receptor in croaker gonads and preliminary evidence for the presence of a GPR30-like protein in fish gonads are discussed. Finally, initial characterization of the ligand binding, G-protein activation and molecular size of a membrane androgen receptor (mAR) in croaker ovaries suggests the presence of a third unique steroid receptor in fish gonads that also may function as a GPCR.
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Affiliation(s)
- Peter Thomas
- University of Texas at Austin, Marine Science Institute, Port Aransas, 78374, USA.
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Younglai EV, Wu Y, Foster WG. Rapid action of pesticides on cytosolic calcium concentrations in cultures of human umbilical vein endothelial cells. Reprod Toxicol 2005; 21:271-9. [PMID: 16243481 DOI: 10.1016/j.reprotox.2005.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Revised: 08/17/2005] [Accepted: 09/21/2005] [Indexed: 11/16/2022]
Abstract
Persistent metabolites of pesticides such as p,p'-DDE, at environmentally relevant concentrations, have been shown to have a rapid effect on intracellular calcium [Ca2+]i concentrations in human granulosa-lutein cells. Since endocrine disrupting substances can be transferred from the maternal circulation to the fetus the present study examined whether the pesticides, kepone, o,p-DDE, p,p'-DDE and methoxychlor, could alter cytoplasmic calcium [Ca2+]cyt concentrations in human umbilical vein endothelial (HUVE) cells. Cultured HUVE cells were loaded with Fura-2 AM and changes in [Ca2+]cyt of single cells were studied using a dynamic digital Ca2+ imaging system. Kepone and methoxychlor consistently increased [Ca2+]cyt concentrations, similar to the effects of estradiol and progesterone. p,p'-DDE increased [Ca2+]cyt concentrations in 80% of experiments whereas o,p-DDE stimulated its increases in 42%. Estrone, estriol, pregnenolone and cortisol were not effective. These results demonstrate that pesticides can have a rapid effect on HUVE cells probably through a nongenomic mechanism of action.
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Affiliation(s)
- Edward V Younglai
- Department of Obstetrics & Gynecology, Reproductive Biology Division, McMaster University Medical Centre, 1200 Main Street West, Health Sciences Centre, Hamilton, Ont., Canada L8N 3Z5.
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