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Molecular, genetic and epigenetic pathways of peroxynitrite-induced cellular toxicity. Interdiscip Toxicol 2009; 2:219-28. [PMID: 21217858 PMCID: PMC2984115 DOI: 10.2478/v10102-009-0020-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 09/25/2009] [Accepted: 10/01/2009] [Indexed: 02/07/2023] Open
Abstract
Oxidative stress plays a key role in the pathogenesis of cancer and many metabolic diseases; therefore, an effective antioxidant therapy would be of great importance in these circumstances. Nevertheless, convincing randomized clinical trials revealed that antioxidant supplementations were not associated with significant reduction in incidence of cancer, chronic diseases and all-cause mortality. As oxidation of essential molecules continues, it turns to nitro-oxidative stress because of the involvement of nitric oxide in pathogenesis processes. Peroxynitrite damages via several distinctive mechanisms; first, it has direct toxic effects on all biomolecules and causes lipid peroxidation, protein oxidation and DNA damage. The second mechanism involves the induction of several transcription factors leading to cytokine-induced chronic inflammation. Finally, it causes epigenetic perturbations that exaggerate nuclear factor kappa-B mediated inflammatory gene expression. Lessons-learned from the treatment of several chronic disorders including pulmonary diseases suggest that, chronic inflammation and glucocorticoid resistance are regulated by prolonged peroxynitrite production.
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152
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Guerrero-Bosagna CM, Skinner MK. Epigenetic transgenerational effects of endocrine disruptors on male reproduction. Semin Reprod Med 2009; 27:403-8. [PMID: 19711250 DOI: 10.1055/s-0029-1237428] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Endocrine-disrupting chemicals generally function as steroid receptor signaling antagonists or agonists that influence development to promote adult-onset disease. Exposure to the endocrine disruptors during the initiation of male reproductive tract development interferes with the normal hormonal signaling and formation of male reproductive organs. In particular, exposure to the endocrine disruptor vinclozolin promotes transgenerational transmission of adult-onset disease states such as male infertility, increased frequencies of tumors, prostate disease, kidney diseases, and immune abnormalities that develop as males age. An epigenetic change in the germ line would be involved in the transgenerational transmission of these induced phenotypes. Nevertheless, other studies have also reported transgenerational transmission of induced epigenetic changes, without altering the germ line. Here we propose a nomenclature to help clarify both cases of transgenerational epigenetic transmission. An intrinsic epigenetic transgenerational process would require a germ-line involvement, a permanent alteration in the germ cell epigenome, and only one exposure to the environmental factor. An extrinsic epigenetic transgenerational process would involve an epigenetic alteration in a somatic tissue and require exposure at each generation to maintain the transgenerational phenotype.
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Affiliation(s)
- Carlos M Guerrero-Bosagna
- Center for Reproductive Biology, School of Molecular Biosciences, Washington State University, Pullman, Washington 99164-4231, USA
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153
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Bhandari D, Walworth MJ, Sepaniak MJ. Dual function surface-enhanced Raman active extractor for the detection of environmental contaminants. APPLIED SPECTROSCOPY 2009; 63:571-578. [PMID: 19470216 DOI: 10.1366/000370209788347002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Surface-enhanced Raman spectroscopy (SERS) has lagged behind other analytical techniques utilized in routine chemical analyses despite the information-rich spectra produced. This can be attributed in part to the difficulties in finding effective substrates that provide high sensitivity and highly reproducible SERS responses. Herein, we have developed a silver-coated polypropylene filter (AgPPF) as a highly sensitive and promising SERS substrate for the detection of environmentally significant chemicals, including selected pharmaceuticals, personal care products, and possible endocrine disruptors. The present approach involves preconcentration studies of selected environmental compounds with 3M's High Performance Extraction Disc Cartridges (HPEDCs) and characterization of the same HPEDC filters as a SERS substrate. The polypropylene microfiber prefilter that encloses the empore extraction medium is modified by physical vapor deposition with silver and used as the SERS substrate. The HPEDC itself is used to concentrate analytes into a desired concentration range, achieving maximum sensitivity. Surface roughness and nanoscale structure of silver films on the microfiber were characterized by atomic force microscopy (AFM). The mass thickness of the silver and volume were optimized for the highest SERS signal using rhodamine 6G as a model compound. A novel component of our HPEDC studies involves the hyphenation of the concentration protocol and SERS. The hyphenation of sample concentration and SERS allows more sensitive surface-enhanced detection. Mitoxanthrone dihydrochloride, crystal violet dye, 4-aminobenzoic acid, and rhodamine 6G were employed to study the sensitive SERS detection and were observed as low as 5 x 10(-8) M to 1 x 10(-10) M without any preconcentration step. Additionally, SERS signatures of some flavonoids, targeted as possible Endocrine Disrupting Chemicals by the US Environmental Protection Agency, such as Apigenin and Daidzein, are reported along with their sensitive detection down to ng/mL for the first time with preconcentration.
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Affiliation(s)
- Deepak Bhandari
- The University of Tennessee, Department of Chemistry, Knoxville, TN 37996, USA
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154
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Satre D, Reichert M, Corbitt C. Effects of vinclozolin, an anti-androgen, on affiliative behavior in the Dark-eyed Junco, Junco hyemalis. ENVIRONMENTAL RESEARCH 2009; 109:400-404. [PMID: 19261272 DOI: 10.1016/j.envres.2009.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 01/08/2009] [Accepted: 01/15/2009] [Indexed: 05/27/2023]
Abstract
Endocrine disrupting chemicals (EDCs) produce changes in physiology and behavior via diverse mechanisms including acting as hormone mimics or antagonists, affecting intracellular signaling pathways, and altering hormone production pathways. The fungicide vinclozolin acts as an anti-androgen and is known to affect affiliative behaviors in rodents, fish and amphibians. To investigate the possible effects of exposure to EDCs on reproductive behavior in a wild population of songbirds, we examined the effects of vinclozolin in wild-caught Dark-eyed Juncos (Junco hyemalis). For this and many other temperate songbird species, testosterone has powerful activational effects on affiliative behaviors in adulthood. We hypothesized that vinclozolin would affect male behaviors associated with female preference. Male juncos received daily oral gavage for 10 weeks with 2mM vinclozolin in vehicle or vehicle alone. Juncos were photostimulated (16L:8D) to induce breeding behavior. Each pair of a treated and non-treated male was presented to an estrogen-primed female to assess female preference. Seven of eight females exhibited a strong preference for a male exposed to vinclozolin over a control male (p=0.01). The only significant difference in measured male behaviors was increased beak wiping in controls (p=0.006) and there was no difference in gonad size or brain weight (p>0.05 for each). Our data suggest that estrogen-primed female juncos prefer to associate with male juncos exposed to this anti-androgen. This finding demonstrates that environmentally occurring anti-androgens can affect the social behavior of this species. To our knowledge, this is the first study to show that vinclozolin has effects on the social behavior of songbirds.
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Affiliation(s)
- Danielle Satre
- Department of Biology, University of Louisville, 139 Life Sciences, Louisville, KY 40292, USA
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155
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Albrecht ED, Lane MV, Marshall GR, Merchenthaler I, Simorangkir DR, Pohl CR, Plant TM, Pepe GJ. Estrogen promotes germ cell and seminiferous tubule development in the baboon fetal testis. Biol Reprod 2009; 81:406-14. [PMID: 19403930 DOI: 10.1095/biolreprod.108.073494] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The foundation for development of the male reproduction system occurs in utero, but relatively little is known about the regulation of primate fetal testis maturation. Our laboratories have shown that estrogen regulates key aspects of the physiology of pregnancy and fetal development. Therefore, in the present study, we characterized and quantified germ cells and Sertoli cells in the fetal baboon testis in late normal gestation (i.e., Day 165; term is 184 days) and in baboons administered the aromatase inhibitor letrozole throughout the second half of gestation to assess the impact of endogenous estrogen on fetal testis development. In untreated baboons, the seminiferous cords were comprised of undifferentiated (i.e., type A) spermatogonia classified by their morphology as dark (Ad) or pale (Ap), gonocytes (precursors of type A spermatogonia), unidentified cells (UI), and Sertoli cells. In letrozole-treated baboons, serum estradiol levels were decreased by 95%. The number per milligram of fetal testis (x10(4)) of Ad spermatogonia (0.42 +/- 0.11) was 45% lower (P = 0.03), and that of gonocytes (0.58 +/- 0.06) and UI (0.45 +/- 0.12) was twofold greater (P < 0.01 and P = 0.06, respectively), than in untreated baboons. Moreover, in the seminiferous cords of estrogen-deprived baboons, the basement membrane appeared fragmented, the germ cells and Sertoli cells appeared disorganized, and vacuoles were present. We conclude that endogenous estrogen promotes fetal testis development and that the changes in the germ cell population in the estrogen-deprived baboon fetus may impair spermatogenesis and fertility in adulthood.
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Affiliation(s)
- Eugene D Albrecht
- Department of Obstetrics, Center for Studies in Reproduction, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
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156
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Keay J, Thornton JW. Hormone-activated estrogen receptors in annelid invertebrates: implications for evolution and endocrine disruption. Endocrinology 2009; 150:1731-8. [PMID: 19036877 PMCID: PMC2659264 DOI: 10.1210/en.2008-1338] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 11/18/2008] [Indexed: 12/30/2022]
Abstract
As the primary mediators of estrogen signaling in vertebrates, estrogen receptors (ERs) play crucial roles in reproduction, development, and behavior. They are also the major mediators of endocrine disruption by xenobiotic pollutants that mimic or block estrogen action. ERs that are sensitive to estrogen and endocrine disrupters have long been thought to be restricted to vertebrates: although there is evidence for estrogen signaling in invertebrates, the only ERs studied to date, from mollusks and cephalochordates, have been insensitive to estrogen and therefore incapable of mediating estrogen signaling or disruption. To determine whether estrogen sensitivity is ancestral or a unique characteristic of vertebrate ERs, we isolated and characterized ERs from two annelids, Platynereis dumerilii and Capitella capitata, because annelids are the sister phylum to mollusks and have been shown to produce and respond to estrogens. Functional assays show that annelid ERs specifically activate transcription in response to low estrogen concentrations and bind estrogen with high affinity. Furthermore, numerous known endocrine-disrupting chemicals activate or antagonize the annelid ER. This is the first report of a hormone-activated invertebrate ER. Our results indicate that estrogen signaling via the ER is as ancient as the ancestral bilaterian animal and corroborate the estrogen sensitivity of the ancestral steroid receptor. They suggest that the taxonomic scope of endocrine disruption by xenoestrogens may be very broad and reveal how functional diversity evolved in a gene family central to animal endocrinology.
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Affiliation(s)
- June Keay
- Center for Ecology and Evolutionary Biology, University of Oregon, Eugene, Oregon 97403, USA
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157
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Sassi-Messai S, Gibert Y, Bernard L, Nishio SI, Ferri Lagneau KF, Molina J, Andersson-Lendahl M, Benoit G, Balaguer P, Laudet V. The phytoestrogen genistein affects zebrafish development through two different pathways. PLoS One 2009; 4:e4935. [PMID: 19319186 PMCID: PMC2655710 DOI: 10.1371/journal.pone.0004935] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2008] [Accepted: 02/10/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Endocrine disrupting chemicals are widely distributed in the environment and derive from many different human activities or can also be natural products synthesized by plants or microorganisms. The phytoestrogen, genistein (4', 5, 7-trihydroxy-isoflavone), is a naturally occurring compound found in soy products. Genistein has been the subject of numerous studies because of its known estrogenic activity. METHODOLOGY/PRINCIPAL FINDINGS We report that genistein exposure of zebrafish embryos induces apoptosis, mainly in the hindbrain and the anterior spinal cord. Timing experiments demonstrate that apoptosis is induced during a precise developmental window. Since adding ICI 182,780, an ER antagonist, does not rescue the genistein-induced apoptosis and since there is no synergistic effect between genistein and estradiol, we conclude that this apoptotic effect elicited by genistein is estrogen-receptors independent. However, we show in vitro, that genistein binds and activates the three zebrafish estrogen receptors ERalpha, ERbeta-A and ERbeta-B. Furthermore using transgenic ERE-Luciferase fish we show that genistein is able to activate the estrogen pathway in vivo during larval stages. Finally we show that genistein is able to induce ectopic expression of the aromatase-B gene in an ER-dependent manner in the anterior brain in pattern highly similar to the one resulting from estrogen treatment at low concentration. CONCLUSION/SIGNIFICANCE TAKEN TOGETHER THESE RESULTS INDICATE THAT GENISTEIN ACTS THROUGH AT LEAST TWO DIFFERENT PATHWAYS IN ZEBRAFISH EMBRYOS: (i) it induces apoptosis in an ER-independent manner and (ii) it regulates aromatase-B expression in the brain in an ER-dependent manner. Our results thus highlight the multiplicity of possible actions of phytoestrogens, such as genistein. This suggests that the use of standardized endpoints to study the effect of a given compound, even when this compound has well known targets, may carry the risk of overlooking interesting effects of this compound.
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Affiliation(s)
- Sana Sassi-Messai
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Yann Gibert
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Laure Bernard
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Shin-Ichi Nishio
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Karine F. Ferri Lagneau
- Apoptosis and Oncogenesis Laboratory, Institut de Biologie et Chimie des Protéines, Université de Lyon, Université Lyon 1, Institut Fédératif Biosciences Gerland Lyon Sud, CNRS, Lyon, France
| | - José Molina
- Equipe INSERM U896 Institut de Recherche en Cancérologie de Montpellier (IRCM), Montpellier, France
| | - Monika Andersson-Lendahl
- Karolinska Institutet, Department of Biosciences and Nutrition, Laboratory of Medical Nutrition, Stockholm, Sweden
| | - Gérard Benoit
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Patrick Balaguer
- Equipe INSERM U896 Institut de Recherche en Cancérologie de Montpellier (IRCM), Montpellier, France
| | - Vincent Laudet
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon, France
- * E-mail:
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158
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Tan SW, Meiller JC, Mahaffey KR. The endocrine effects of mercury in humans and wildlife. Crit Rev Toxicol 2009; 39:228-69. [DOI: 10.1080/10408440802233259] [Citation(s) in RCA: 206] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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159
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Hashimoto S, Watanabe E, Ikeda M, Terao Y, Strüssmann CA, Inoue M, Hara A. Effects of ethinylestradiol on medaka (Oryzias latipes) as measured by sperm motility and fertilization success. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 56:253-259. [PMID: 18506499 DOI: 10.1007/s00244-008-9183-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Accepted: 05/16/2008] [Indexed: 05/26/2023]
Abstract
We investigated the effects of 30-480 ng/L 17alpha-ethinylestradiol (EE(2)) on the sperm motility and fertility of Japanese medaka (Oryzias latipes). Sperm motility was examined by computer-assisted image analysis. In male medaka, the velocity of sperm was found to have increased after 3 weeks of exposure at 60-480 ng/L. This result suggests that higher sperm velocities depleted sperm energy reserves more rapidly and shortened the time for which sperm were viable to fertilize eggs. In a separate experiment that studied whether EE(2) exposure of males affects the fertilization rate or hatchability, sexually mature male medaka were exposed for 3 weeks and subsequently evaluated for their reproductive ability after pairing with unexposed females for 7 days. Exposure of males to EE(2) exerted a potent inhibitory effect on a reproduction parameter (fertilization rate x hatchability), and the highest inhibition was observed at 60 ng/L. The results offer toxicological data for the assessment of EE(2 )exposure in medaka and suggest that short-term exposure to EE(2) might reduce sperm function and fertility in adult male medaka.
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Affiliation(s)
- Shinya Hashimoto
- Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
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160
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Ducolomb Y, Casas E, Valdez A, González G, Altamirano-Lozano M, Betancourt M. In vitro effect of malathion and diazinon on oocytes fertilization and embryo development in porcine. Cell Biol Toxicol 2009; 25:623-33. [DOI: 10.1007/s10565-008-9117-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Accepted: 12/19/2008] [Indexed: 02/02/2023]
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161
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Iguchi T, Katsu Y. Commonality in Signaling of Endocrine Disruption from Snail to Human. Bioscience 2008. [DOI: 10.1641/b581109] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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162
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Katsu Y, Kohno S, Hyodo S, Ijiri S, Adachi S, Hara A, Guillette LJ, Iguchi T. Molecular cloning, characterization, and evolutionary analysis of estrogen receptors from phylogenetically ancient fish. Endocrinology 2008; 149:6300-10. [PMID: 18635653 PMCID: PMC2734497 DOI: 10.1210/en.2008-0670] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estrogens are necessary for ovarian differentiation during a critical developmental stage in many vertebrates, and they promote the growth and differentiation of the adult female reproductive system. To understand the evolution of vertebrate estrogen receptors (ESRs) and to evaluate estrogen receptor-ligand interactions in phylogenetically ancient fish, we used PCR techniques to isolate the cDNA encoding ESRs from lungfish, sturgeon, and gar. Sequence analyses indicate that these fishes have two ESRs, ESR1 (ERalpha) and ESR2 (ERbeta), as previously reported for other vertebrate species, but a second type of ESR2 (ERbeta2) was not found as has been reported in a number of teleost fishes. Phylogenetic analysis of the ESR sequences indicated that the lungfish ESRs are classified to the tetrapod ESR group, not with the teleost fish ESRs as are the ESRs from gar and sturgeon. Using transient transfection assays of mammalian cells, ESR proteins from these three ancient fishes displayed estrogen-dependent activation of transcription from an estrogen-responsive-element containing promoter. We also examined the estrogenic potential of o,p'-dichloro-diphenyl-trichloroethane (o,p'-DDT) and p,p'-DDT as well as one of its common metabolites, p,p'-dichloro-diphenyl-ethylene (p,p'-DDE) on the ESRs from these fishes. Lungfish ESR1 was less sensitive to DDT/DDE than the ESR1 from the other two fishes. The response of lungfish ESR1 to these pesticides is similar to the pattern obtained from salamander ESR1. These data provide a basic tool allowing future studies examining the receptor-ligand interactions and endocrine-disrupting mechanisms in three species of phylogenetically ancient fish and also expands our knowledge of ESR evolution.
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Affiliation(s)
- Yoshinao Katsu
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
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163
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Recabarren SE, Rojas-García PP, Recabarren MP, Alfaro VH, Smith R, Padmanabhan V, Sir-Petermann T. Prenatal testosterone excess reduces sperm count and motility. Endocrinology 2008; 149:6444-8. [PMID: 18669598 DOI: 10.1210/en.2008-0785] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The reproductive system is extremely susceptible to insults from exposure to exogenous steroids during development. Excess prenatal testosterone exposure programs neuroendocrine, ovarian, and metabolic deficits in the female, features seen in women with polycystic ovary disease. The objective of this study was to determine whether prenatal testosterone excess also disrupts the male reproductive system, using sheep as a model system. The extent of reproductive disruption was tested by assessing sperm quantity and quality as well as Leydig cell responsiveness to human chorionic gonadotropin. Males born to mothers treated with 30 mg testosterone propionate twice weekly from d 30 to 90 and with 40 mg testosterone propionate from d 90 to 120 of pregnancy (T-males) showed a significant reduction (P < 0.05) in body weight, scrotal circumference, and sperm count compared with control males. Mean straight line velocity of sperms was also lower in T-males (P < 0.05). Circulating testosterone levels in response to the human chorionic gonadotropin did not differ between groups. These findings demonstrate that exposure to excess testosterone during fetal development has a negative impact on reproductive health of the male offspring, raising concerns relative to unintended human exposure to steroidal mimics in the environment.
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Affiliation(s)
- Sergio E Recabarren
- Laboratory of Animal Physiology and Endocrinology, Faculty of Veterinary Sciences, University of Concepcion, Casilla 537, Chillan, Chile.
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164
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Crain DA, Janssen SJ, Edwards TM, Heindel J, Ho SM, Hunt P, Iguchi T, Juul A, McLachlan JA, Schwartz J, Skakkebaek N, Soto AM, Swan S, Walker C, Woodruff TK, Woodruff TJ, Giudice LC, Guillette LJ. Female reproductive disorders: the roles of endocrine-disrupting compounds and developmental timing. Fertil Steril 2008; 90:911-40. [PMID: 18929049 DOI: 10.1016/j.fertnstert.2008.08.067] [Citation(s) in RCA: 300] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 08/13/2008] [Indexed: 12/21/2022]
Abstract
OBJECTIVE To evaluate the possible role of endocrine-disrupting compounds (EDCs) on female reproductive disorders emphasizing developmental plasticity and the complexity of endocrine-dependent ontogeny of reproductive organs. Declining conception rates and the high incidence of female reproductive disruptions warrant evaluation of the impact of EDCs on female reproductive health. DESIGN Publications related to the contribution of EDCs to disorders of the ovary (aneuploidy, polycystic ovary syndrome, and altered cyclicity), uterus (endometriosis, uterine fibroids, fetal growth restriction, and pregnancy loss), breast (breast cancer, reduced duration of lactation), and pubertal timing were identified, reviewed, and summarized at a workshop. CONCLUSION(S) The data reviewed illustrate that EDCs contribute to numerous human female reproductive disorders and emphasize the sensitivity of early life-stage exposures. Many research gaps are identified that limit full understanding of the contribution of EDCs to female reproductive problems. Moreover, there is an urgent need to reduce the incidence of these reproductive disorders, which can be addressed by correlative studies on early life exposure and adult reproductive dysfunction together with tools to assess the specific exposures and methods to block their effects. This review of the EDC literature as it relates to female health provides an important platform on which women's health can be improved.
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165
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McCoy KA, Bortnick LJ, Campbell CM, Hamlin HJ, Guillette LJ, St Mary CM. Agriculture alters gonadal form and function in the toad Bufo marinus. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:1526-32. [PMID: 19057706 PMCID: PMC2592273 DOI: 10.1289/ehp.11536] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Accepted: 07/03/2008] [Indexed: 05/02/2023]
Abstract
BACKGROUND Many agricultural contaminants disrupt endocrine systems of wildlife. However, evidence of endocrine disruption in wild amphibians living in agricultural areas has been controversial. Typically, studies on the effects of pollutants on wildlife attempt to compare polluted with unpolluted sites. OBJECTIVES We took a novel approach to address this question by explicitly quantifying the relationship between gonadal abnormalities and habitats characterized by differing degrees of agricultural activity. METHODS We quantified the occurrence of gonadal abnormalities and measures of gonadal function in at least 20 giant toads (Bufo marinus) from each of five sites that occur along a gradient of increasing agricultural land use from 0 to 97%. RESULTS The number of abnormalities and frequency of intersex gonads increased with agriculture in a dose-dependent fashion. These gonadal abnormalities were associated with altered gonadal function. Testosterone, but not 17beta-estradiol, concentrations were altered and secondary sexual traits were either feminized (increased skin mottling) or demasculinized (reduced forearm width and nuptial pad number) in intersex toads. Based on the end points we examined, female morphology and physiology did not differ across sites. However, males from agricultural areas had hormone concentrations and secondary sexual traits that were intermediate between intersex toads and non-agricultural male toads. Skin coloration at the most agricultural site was not sexually dimorphic; males had female coloration. CONCLUSIONS Steroid hormone concentrations and secondary sexual traits correlate with reproductive activity and success, so affected toads likely have reduced reproductive success. These reproductive abnormalities could certainly contribute to amphibian population declines occurring in areas exposed to agricultural contaminants.
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Affiliation(s)
- Krista A McCoy
- School of Natural Resources and Environment, University of Florida, Gainesville, Florida, USA.
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166
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Guerrero-Bosagna CM, Sabat P, Valdovinos FS, Valladares LE, Clark SJ. Epigenetic and phenotypic changes result from a continuous pre and post natal dietary exposure to phytoestrogens in an experimental population of mice. BMC PHYSIOLOGY 2008; 8:17. [PMID: 18793434 PMCID: PMC2556694 DOI: 10.1186/1472-6793-8-17] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 09/15/2008] [Indexed: 02/04/2023]
Abstract
BACKGROUND Developmental effects of exposure to endocrine disruptors can influence adult characters in mammals, but could also have evolutionary consequences. The aim of this study was to simulate an environmental exposure of an experimental population of mice to high amounts of nutritional phytoestrogens and to evaluate parameters of relevance for evolutionary change in the offspring. The effect of a continuous pre- and post-natal exposure to high levels of dietary isoflavones was evaluated on sexual maturity, morphometric parameters and DNA methylation status in mice. Adult mice male/female couples were fed ad libitum either with control diet (standard laboratory chow) or ISF diet (control diet plus a soy isoflavone extract at 2% (w/w) that contained the phytoestrogens genistein and daidzein). In the offspring we measured: i) the onset of vaginal opening (sexual maturation) in females, ii) weight and size in all pups at 7, 14, 21 and 42 days post-natal (dpn) and iii) DNA methylation patterns in skeletal alpha-actin (Acta1), estrogen receptor-alpha and c-fos in adults (42 dpn). RESULTS Vaginal opening was advanced in female pups in the ISF group, from 31.6 +/- 0.75 dpn to 25.7 +/- 0.48. No differences in size or weight at ages 7, 14 or 21 dpn were detected between experimental groups. Nevertheless, at age 42 dpn reduced size and weight were observed in ISF pups, in addition to suppression of normal gender differences in weight seen in the control group (males heavier that females). Also, natural differences seen in DNA methylation at Acta1 promoter in the offspring originated in the control group were suppressed in the ISF group. Acta1 is known to be developmentally regulated and related to morphomotric features. CONCLUSION This study demonstrates in mammals that individuals from a population subjected to a high consumption of isoflavones can show alterations in characters that may be of importance from an evolutionary perspective, such as epigenetic and morphometric characters or sexual maturation, a life history character.
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Affiliation(s)
- Carlos M Guerrero-Bosagna
- Center for Reproductive Biology, School of Molecular Biosciences, Washington State University, Pullman, WA, 99164-4231, USA
- Laboratorio de Ecofisiología Animal, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Laboratorio de Hormonas y Receptores, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
- Epigenetics Laboratory, Cancer Program, Garvan Institute of Medical Research, Sydney, Australia
| | - Pablo Sabat
- Laboratorio de Ecofisiología Animal, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Center for Advanced Studies in Ecology & Biodiversity and Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica, de Chile, Santiago, Chile
| | - Fernanda S Valdovinos
- Laboratorio de Ecofisiología Animal, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Luis E Valladares
- Laboratorio de Hormonas y Receptores, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Susan J Clark
- Epigenetics Laboratory, Cancer Program, Garvan Institute of Medical Research, Sydney, Australia
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Foresta C, Zuccarello D, Garolla A, Ferlin A. Role of hormones, genes, and environment in human cryptorchidism. Endocr Rev 2008; 29:560-80. [PMID: 18436703 DOI: 10.1210/er.2007-0042] [Citation(s) in RCA: 152] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cryptorchidism is the most frequent congenital birth defect in male children (2-4% in full-term male births), and it has the potential to impact the health of the human male. In fact, although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. Furthermore, some reports have highlighted a significant increase in the prevalence of cryptorchidism over the last few decades. Etiology of cryptorchidism remains for the most part unknown, and cryptorchidism itself might be considered a complex disease. Major regulators of testicular descent from intraabdominal location into the bottom of the scrotum are the Leydig-cell-derived hormones testosterone and insulin-like factor 3. Research on possible genetic causes of cryptorchidism has increased recently. Abundant animal evidence supports a genetic cause, whereas the genetic contribution to human cryptorchidism is being elucidated only recently. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene have been recognized as causes of cryptorchidism in some cases, but some chromosomal alterations, above all the Klinefelter syndrome, are also frequently involved. Environmental factors acting as endocrine disruptors of testicular descent might also contribute to the etiology of cryptorchidism and its increased incidence in recent years. Furthermore, polymorphisms in different genes have recently been investigated as contributing risk factors for cryptorchidism, alone or by influencing susceptibility to endocrine disruptors. Obviously, the interaction of environmental and genetic factors is fundamental, and many aspects have been clarified only recently.
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Affiliation(s)
- Carlo Foresta
- University of Padova, Department of Histology, Microbiology and Medical Biotechnologies, Section of Clinical Pathology and Centre for Male Gamete Cryopreservation, Via Gabelli 63, 35121 Padova, Italy.
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Sciarrillo R, De Falco M, Virgilio F, Laforgia V, Capaldo A, Gay F, Valiante S, Varano L. Morphological and functional changes in the thyroid gland of methyl thiophanate-injected lizards, Podarcis sicula. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2008; 55:254-261. [PMID: 18196192 DOI: 10.1007/s00244-007-9116-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Accepted: 12/10/2007] [Indexed: 05/25/2023]
Abstract
The thyroid has been shown to be a target organ for environmental chemicals, specifically endocrine-disrupting contaminants. Reptiles are particularly suitable as contaminant biomonitors due to their persistence in a variety of habitats, wide geographic distribution, longevity, and, in many cases, site fidelity. Methyl thiophanate is a systemic broad-spectrum fungicide used to prevent and control plant diseases caused by various fungi. The aim of this study was to develop an integrated biological model for monitoring the ecotoxic effects of thiophanate-methyl fungicide on the thyroid of the lizard Podarcis sicula. The results of this study indicate that both structural and functional differences in the thyroid gland of the lizard exist in the animals exposed to methyl thiophanate. Structurally, animals exposed to methyl thiophanate showed decreased epithelial cell height; the nuclei of the thyroid cells were small and elongated with dense chromatin and a greatly reduced cytoplasm. The colloid was retracted with few reabsorption vacuoles. Functionally, the same animals exhibited decreased T4 and T3 plasma levels compared to control animals. Methyl thiophanate administration produced statistically significant inhibition on serum thyroid-stimulating hormone levels and this is the mechanism for altering thyroid function. This study highlights how thyroid gland disruption, both structural and functional, in lizard and other nontarget organisms might also have an environmental aetiology.
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Affiliation(s)
- Rosaria Sciarrillo
- Dipartimento di Scienze Biologiche e Ambientali, Università degli Studi del Sannio, Benevento, Italy.
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170
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Multigner L, Kadhel P, Pascal M, Huc-Terki F, Kercret H, Massart C, Janky E, Auger J, Jégou B. Parallel assessment of male reproductive function in workers and wild rats exposed to pesticides in banana plantations in Guadeloupe. Environ Health 2008; 7:40. [PMID: 18667078 PMCID: PMC2519067 DOI: 10.1186/1476-069x-7-40] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 07/30/2008] [Indexed: 05/07/2023]
Abstract
BACKGROUND There is increasing evidence that reproductive abnormalities are increasing in frequency in both human population and among wild fauna. This increase is probably related to exposure to toxic contaminants in the environment. The use of sentinel species to raise alarms relating to human reproductive health has been strongly recommended. However, no simultaneous studies at the same site have been carried out in recent decades to evaluate the utility of wild animals for monitoring human reproductive disorders. We carried out a joint study in Guadeloupe assessing the reproductive function of workers exposed to pesticides in banana plantations and of male wild rats living in these plantations. METHODS A cross-sectional study was performed to assess semen quality and reproductive hormones in banana workers and in men working in non-agricultural sectors. These reproductive parameters were also assessed in wild rats captured in the plantations and were compared with those in rats from areas not directly polluted by humans. RESULTS No significant difference in sperm characteristics and/or hormones was found between workers exposed and not exposed to pesticide. By contrast, rats captured in the banana plantations had lower testosterone levels and gonadosomatic indices than control rats. CONCLUSION Wild rats seem to be more sensitive than humans to the effects of pesticide exposure on reproductive health. We conclude that the concept of sentinel species must be carefully validated as the actual nature of exposure may varies between human and wild species as well as the vulnerable time period of exposure and various ecological factors.
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Affiliation(s)
- Luc Multigner
- Inserm, U625, Rennes, France
- Université Rennes 1, IFR 140, Rennes, France
| | - Philippe Kadhel
- Inserm, U625, Rennes, France
- Université Rennes 1, IFR 140, Rennes, France
- Service Gynécologie-Obstétrique, CHU, Guadeloupe
- Université des Antilles et de la Guyane, Guadeloupe
| | - Michel Pascal
- INRA, Station SCRIBE, Équipe Gestion des Populations Invasives, Rennes, France
| | | | - Henri Kercret
- Inserm, U625, Rennes, France
- Université Rennes 1, IFR 140, Rennes, France
| | | | - Eustase Janky
- Service Gynécologie-Obstétrique, CHU, Guadeloupe
- Université des Antilles et de la Guyane, Guadeloupe
| | - Jacques Auger
- Service d'Histologie-Embryologie et de Biologie de la Reproduction, CECOS, CHU Cochin, Paris, France
| | - Bernard Jégou
- Inserm, U625, Rennes, France
- Université Rennes 1, IFR 140, Rennes, France
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Wang Y, Barthold J, Figueroa E, González R, Noh PH, Wang M, Manson J. Analysis of five single nucleotide polymorphisms in the ESR1 gene in cryptorchidism. ACTA ACUST UNITED AC 2008; 82:482-5. [PMID: 18452179 DOI: 10.1002/bdra.20458] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Recent findings suggest that a specific haplotype, including five single nucleotide polymorphisms (SNPs) in the 3'-terminal region of the estrogen receptor alpha gene (ESR1), is associated with the risk for cryptorchidism, but results have been conflicting in different populations. The goal of this study was to further define the association between this specific ESR1 haplotype and the risk for nonsyndromic cryptorchidism in a multiracial American population including Caucasian, African American, and Asian American subjects. METHODS Applied Biosystems TaqMan SNP Genotyping Assays were used to identify the genotypes of the five SNPs in ESR1 in 152 nonsyndromic cryptorchidism cases and 160 healthy controls. RESULTS For the five SNPs, there were no significant differences in genotype frequencies between cases and controls. The four estimated haplotypes at the 3' region of ESR1 gene were also not associated with the occurrence of cryptorchidism, but the haplotype AGATC was associated with the severity of cryptorchidism. SNP12 (rs6932902) in ESR1 was not associated with cryptorchidism per se, but was associated with increasing severity of cryptorchidism. Severe cases were more likely to have GG genotype (93%) than moderate (54%) cases (p = .04), and this association was in recessive mode (p = .02). The allele distribution of this SNP was also significantly different between moderate and severe cases: 97% of severe cases had the G allele while only 76% of moderate cases had the G allele (p = .03). CONCLUSIONS SNP12 in ESR1 is not associated with the occurrence of cryptorchidism but is associated with the severity of cryptorchidism.
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Affiliation(s)
- Yanping Wang
- Division of Human Genetics and Molecular Biology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
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172
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Korkmaz A, Sanchez-Barcelo EJ, Tan DX, Reiter RJ. Role of melatonin in the epigenetic regulation of breast cancer. Breast Cancer Res Treat 2008; 115:13-27. [PMID: 18592373 DOI: 10.1007/s10549-008-0103-5] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Accepted: 06/12/2008] [Indexed: 11/24/2022]
Abstract
The oncostatic properties of melatonin as they directly or indirectly involve epigenetic mechanisms of cancer are reviewed with a special focus on breast cancer. Five lines of evidence suggest that melatonin works via epigenetic processes: (1) melatonin influences transcriptional activity of nuclear receptors (ERalpha, GR and RAR) involved in the regulation of breast cancer cell growth; (2) melatonin down-regulates the expression of genes responsible for the local synthesis or activation of estrogens including aromatase, an effect which may be mediated by methylation of the CYP19 gene or deacetylation of CYP19 histones; (3) melatonin inhibits telomerase activity and expression induced by either natural estrogens or xenoestrogens; (4) melatonin modulates the cell cycle through the inhibition of cyclin D1 expression; (5) melatonin influences circadian rhythm disturbances dependent on alterations of the light/dark cycle (i.e., light at night) with the subsequent deregulation of PER2 which acts as a tumor suppressor gene.
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Affiliation(s)
- Ahmet Korkmaz
- Department of Physiology, School of Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
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173
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Kohno S, Bermudez DS, Katsu Y, Iguchi T, Guillette LJ. Gene expression patterns in juvenile American alligators (Alligator mississippiensis) exposed to environmental contaminants. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2008; 88:95-101. [PMID: 18455813 DOI: 10.1016/j.aquatox.2008.03.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Revised: 03/04/2008] [Accepted: 03/13/2008] [Indexed: 05/26/2023]
Abstract
Reproductive and developmental abnormalities have been reported in the American alligator (Alligator mississippiensis) population from Lake Apopka, FL, that is chronically exposed to a complex mixture of environmental contaminants. To begin to understand the molecular mechanisms that could lead to the observed abnormalities of the reproductive and endocrine system, we quantified concentrations of the steroid hormones testosterone (T) and estradiol-17beta (E(2)) and expression of steroid hormone receptors and genes relating to steroidogenesis in gonadal tissue from juvenile alligators from three lakes in Florida using enzyme immunoassay and quantitative real-time polymerase chain reaction. Alterations of ESR2 (estrogen receptor beta) and SF1 (steroidogenic factor 1) mRNA expression in male gonadal tissue, without an observed difference in plasma concentrations of T, from the different lakes, begin to provide insight into potential mechanisms underlying the alterations of the reproductive system previously observed. Likewise, alterations in P450 aromatase and DAX1 (dosage-sensitive sex reversal, adrenal hypoplasia congenita critical region on the X chromosome, gene 1) mRNA expression, with elevated plasma E(2) concentrations in females, provide leads to the potential mechanisms modifying folliculogenesis and ovarian development. The investigation of these genes also helps clarify normal endocrine and reproductive system function in the American alligator.
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Affiliation(s)
- Satomi Kohno
- Department of Zoology, 223 Bartram Hall, PO Box 118525, University of Florida, Gainesville, FL 32611-8525, USA.
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174
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Vajda AM, Barber LB, Gray JL, Lopez EM, Woodling JD, Norris DO. Reproductive disruption in fish downstream from an estrogenic wastewater effluent. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:3407-14. [PMID: 18522126 DOI: 10.1021/es0720661] [Citation(s) in RCA: 281] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
To assess the impact of an estrogenic wastewater treatment plant (WWTP) effluent on fish reproduction, white suckers (Catostomus commersoni) were collected from immediately upstream and downstream (effluent site) of the city of Boulder, CO, WWTP outfall. Gonadal intersex, altered sex ratios, reduced gonad size, disrupted ovarian and testicular histopathology, and vitellogenin induction consistent with exposure to estrogenic wastewater contaminants were identified in white suckers downstream from the WWTP outfall and not at the upstream site. The sex ratio was female-biased at the effluent site in both the fall of 2003 and the spring of 2004; the frequency of males at the effluent site (17-21%) was half that of the upstream site (36-46%). Intersex white suckers comprised 18-22% of the population at the effluent site. Intersex fish were not found at the upstream site. Chemical analyses determined that the WWTP effluent contained a complex mixture of endocrine-active chemicals, including 17beta-estradiol (E2) 17alpha-ethynylestradiol, alkylphenols, and bisphenol A resulting in an estimated total estrogen equivalence of up to 31 ng E2 L(-1). These results indicate that the reproductive potential of native fishes may be compromised in wastewater-dominated streams.
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Affiliation(s)
- Alan M Vajda
- Department of Integrative Physiology, University of Colorado, UCB 354, Boulder, Colorado 80309, USA.
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175
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Woodruff TJ, Carlson A, Schwartz JM, Giudice LC. Proceedings of the Summit on Environmental Challenges to Reproductive Health and Fertility: executive summary. Fertil Steril 2008; 89:e1-e20. [PMID: 18308046 DOI: 10.1016/j.fertnstert.2008.01.065] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Revised: 10/03/2007] [Accepted: 10/03/2007] [Indexed: 02/09/2023]
Abstract
The 2007 Summit on Environmental Challenges to Reproductive Health and Fertility convened scientists, health care professionals, community groups, political representatives, and the media to hear presentations on the impact of environmental contaminants on reproductive health and fertility, and to discuss opportunities to improve health through research, education, communication, and policy. Environmental reproductive health focuses on exposures to environmental contaminants, particularly during critical periods of development, and their potential effects on future reproductive health, including conception, fertility, pregnancy, adolescent development, and adult health. Approximately 87,000 chemical substances are registered for commercial use in the United States, with ubiquitous human exposures to environmental contaminants in air, water, food, and consumer products. Exposures during critical windows of susceptibility may result in adverse effects with lifelong and even intergenerational health impacts. Effects can include impaired development and function of the reproductive tract and permanently altered gene expression, leading to metabolic and hormonal disorders, reduced fertility and fecundity, and illnesses such as testicular, prostate, uterine, and cervical cancers later in life. This executive summary reviews effects of pre- and postnatal exposures on male and female reproductive health, and provides a series of recommendations for advancing the field in the areas of research, policy, health care, and community action.
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Affiliation(s)
- Tracey J Woodruff
- Program on Reproductive Health and the Environment, National Center of Excellence in Women's Health, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, California 94143, USA.
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176
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Zimmermann AL, King EA, Dengler E, Scogin SR, Powell WH. An aryl hydrocarbon receptor repressor from Xenopus laevis: function, expression, and role in dioxin responsiveness during frog development. Toxicol Sci 2008; 104:124-34. [PMID: 18385208 DOI: 10.1093/toxsci/kfn066] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Xenopus laevis and other frogs are extremely insensitive to the toxicity of xenobiotic ligands of the aryl hydrocarbon receptor (AHR), including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Premetamorphic life stages are especially insensitive, and they are reported to be refractory to induction of Cytochrome P4501As, which are readily induced in older animals. The AHR repressor (AHRR) is a member of the AHR gene family. AHRR expression is induced by TCDD; it then represses AHR in an apparent negative feedback loop. In this study, we sought to test the hypothesis that constitutive AHRR expression underlies the lack of TCDD responsiveness in frog early life stages. We determined the sequence of an AHRR complimentary DNA encoding an 85.3-kDa protein sharing 52-55% identity with the bHLH/PAS domains of other AHRRs. In transient transfection assays, X. laevis AHRR inhibited TCDD-induced reporter gene expression mediated by either X. laevis AHR paralog, AHR1alpha or AHR1beta. AHRR messenger RNA was expressed at low levels in embryos (Nieuwkoop-Faber stage 33-38; approximately 52 h.p.f.) and was induced approximately twofold following TCDD exposure (42 ng/g wet weight). In contrast, AHRR exhibited higher constitutive expression and was induced more than threefold in tadpoles at stage 52-55 (prometamorphic; approximately 4 weeks postfertilization) and in isolated viscera of stage 62 tadpoles (in the metamorphic climax; approximately 7 weeks postfertilization). Although the magnitude of induction was smaller, the temporal pattern of AHRR expression and inducibility resembled that of CYP1A6. Thus, attenuated transcriptional activation of AHR target genes and low TCDD toxicity in X. laevis embryos cannot be explained by constitutive, high-level expression of AHRR.
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177
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Prins GS, Korach KS. The role of estrogens and estrogen receptors in normal prostate growth and disease. Steroids 2008; 73:233-44. [PMID: 18093629 PMCID: PMC2262439 DOI: 10.1016/j.steroids.2007.10.013] [Citation(s) in RCA: 218] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 10/23/2007] [Accepted: 10/24/2007] [Indexed: 01/05/2023]
Abstract
Estrogens have significant direct and indirect effects on prostate gland development and homeostasis and have been long suspected in playing a role in the etiology of prostatic diseases. Direct effects are mediated through prostatic estrogen receptors alpha (ERalpha) and beta (ERbeta) with expression levels changing over time and with disease progression. The present review examines the evidence for a role of estrogens and specific estrogen receptors in prostate growth, differentiation and disease states including prostatitis, benign prostatic hyperplasia (BPH) and cancer and discusses potential therapeutic strategies for growth regulation via these pathways.
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Affiliation(s)
- Gail S Prins
- Department of Urology, University of Illinois at Chicago, Chicago, IL 60612, USA.
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178
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Carruba G. Estrogen and prostate cancer: an eclipsed truth in an androgen-dominated scenario. J Cell Biochem 2008; 102:899-911. [PMID: 17786930 DOI: 10.1002/jcb.21529] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Prostate cancer is the commonest non-skin cancer in men. Incidence and mortality rates of this tumor vary strikingly throughout the world. Although several factors have been implicated to explain this remarkable variation, lifestyle and dietary factors may play a dominant role, with sex hormones behaving as intermediaries between exogenous factors and molecular targets in development and progression of prostate cancer. Human prostate cancer is generally considered a paradigm of androgen-dependent tumor; however, estrogen role in both normal and malignant prostate appears to be equally important. The association between plasma androgens and prostate cancer remains contradictory and mostly not compatible with the androgen hypothesis. Similar evidence apply to estrogens, although the ratio of androgen to estrogen in plasma declines with age. Apart from methodological problems, a major issue is to what extent circulating hormones can be considered representative of their intraprostatic levels. Both nontumoral and malignant human prostate tissues and cells are endowed with key enzymes of steroid metabolism, including 17betahydroxysteroid dehydrogenase (17betaHSD), 5beta-reductase, 3alpha/3betaHSD, and aromatase. A divergent expression and/or activity of these enzymes may eventually lead to a differential prostate accumulation of steroid derivatives having distinct biological activities, as it occurs for hydroxylated estrogens in the human breast. Locally produced or metabolically transformed estrogens may differently affect proliferative activity of prostate cancer cells. Aberrant aromatase expression and activity has been reported in prostate tumor tissues and cells, implying that androgen aromatization to estrogens may play a role in prostate carcinogenesis or tumor progression. Interestingly, many genes encoding for steroid enzymes are polymorphic, although only a few studies have supported their relation with risk of prostate cancer. In animal model systems estrogens, combined with androgens, appear to be required for the malignant transformation of prostate epithelial cells. Although the mechanisms underlying the hormonal induction of prostate cancer in experimental animals remain uncertain, there is however evidence to support the assumption that long term administration of androgens and estrogens results in an estrogenic milieu in rat prostates and in the ensuing development of dysplasia and cancer. Both androgen and estrogen have been reported to stimulate proliferation of cultured prostate cancer cells, primarily through receptor-mediated effects. As for estrogens, the two major receptor types, ERalpha and ERbeta, are expressed in both normal and diseased human prostate, though with a different cellular localization. Since these two receptors are different in terms of ligand binding, heterodimerization, transactivation, and estrogen response element activity, it is likely that an imbalance of their expression may be critical to determine the ultimate estrogen effects on prostate cancer cells. In prostate cancer, ERbeta activation appears to limit cell proliferation directly or through ERalpha inhibition, and loss of ERbeta has been consistently associated with tumor progression. Several splicing variants of both ERalpha and ERbeta exist. Little is known about their expression and function in the human prostate, although reciprocal regulation and interaction with gene promoter both warrant further investigation. In summary, although multiple consistent evidence suggests that estrogens are critical players in human prostate cancer, their role has been only recently reconsidered, being eclipsed for years by an androgen-dominated interest.
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Affiliation(s)
- Giuseppe Carruba
- Experimental Oncology, Department of Oncology, M. Ascoli Cancer Center, ARNAS-Civico, Palermo, Italy.
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179
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Schoeters G, Den Hond E, Dhooge W, van Larebeke N, Leijs M. Endocrine disruptors and abnormalities of pubertal development. Basic Clin Pharmacol Toxicol 2008; 102:168-75. [PMID: 18226071 DOI: 10.1111/j.1742-7843.2007.00180.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Onset and development of puberty is regulated by the neuroendocrine system. Population-based studies worldwide have observed secular trends towards earlier puberty development. These changes are apparently caused by environmental factors such as improved socio-economic status, improved health care and nutrition. However, they may also partly result from endocrine-disrupting chemicals in the environment. Epidemiological studies have investigated the relationship between pubertal development and exposure to endocrine-disrupting chemicals (polychlorinated biphenyls, polybrominated biphenyls, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, phthalate esters, furans and the pesticide endosulfan). Associations with both perinatal and postnatal exposure have been reported. Studies in experimental animals support some of these findings and point to differential endocrine regulatory mechanisms linked to pubertal development acting in the perinatal and the pre-pubertal period. Pubertal development is naturally associated with growth and body composition. There is increasing evidence for a link between prenatal development and pubertal onset. In girls born small for gestational age (SGA), pubertal onset and age at menarche often are advanced, especially if there has been an extensive catch-up growth during the first months of life. In utero growth retardation may have multiple causes including exposure to xenobiotic substances as was suggested for some endocrine-disrupting chemicals. An abnormal perinatal environment of children born SGA may alter the endocrine status and the sensitivity of the receptors for endocrine and metabolic signalling that may have effects on maturation of brain and gonads. However, the causal pathways and the molecular mechanisms that may link the pubertal growth pattern of children born SGA, pubertal development and endocrine-disrupting chemicals need further study.
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Affiliation(s)
- Greet Schoeters
- Vlaamse Instelling voor Technologisch Onderzoek (VITO), Environmental Toxicology Unit, Mol, Belgium.
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180
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Prins GS, Tang WY, Belmonte J, Ho SM. Perinatal exposure to oestradiol and bisphenol A alters the prostate epigenome and increases susceptibility to carcinogenesis. Basic Clin Pharmacol Toxicol 2008; 102:134-8. [PMID: 18226066 DOI: 10.1111/j.1742-7843.2007.00166.x] [Citation(s) in RCA: 152] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
An important and controversial health concern is whether low-dose exposures to hormonally active environmental oestrogens such as bisphenol A can promote human diseases including prostate cancer. Our studies in rats have shown that pharmacological doses of oestradiol administered during the critical window of prostate development result in marked prostate pathology in adulthood that progress to neoplastic lesions with ageing. Our recent studies have also demonstrated that transient developmental exposure of rats to low, environmentally relevant doses of bisphenol A or oestradiol increases prostate gland susceptibility to adult-onset precancerous lesions and hormonal carcinogenesis. These findings indicate that a wide range of oestrogenic exposures during development can predispose to prostatic neoplasia that suggests a potential developmental basis for this adult disease. To identify a molecular basis for oestrogen imprinting, we screened for DNA methylation changes over time in the exposed prostate glands. We found permanent alterations in DNA methylation patterns of multiple cell signalling genes suggesting an epigenetic mechanism of action. For phosphodiesterase type 4 variant 4 (PDE4D4), an enzyme responsible for intracellular cyclic adenosine monophosphate breakdown, a specific methylation cluster was identified in the 5'-flanking CpG island that was gradually hypermethylated with ageing in normal prostates resulting in loss of gene expression. However, in prostates exposed to neonatal oestradiol or bisphenol A, this region became hypomethylated with ageing resulting in persistent and elevated PDE4D4 expression. In total, these findings indicate that low-dose exposures to ubiquitous environmental oestrogens impact the prostate epigenome during development and in so doing, promote prostate disease with ageing.
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Affiliation(s)
- Gail S Prins
- Department of Urology, University of Illinois at Chicago, Chicago, IL, USA.
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181
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Woodruff TJ, Carlson A, Schwartz JM, Giudice LC. Proceedings of the Summit on Environmental Challenges to Reproductive Health and Fertility: executive summary. Fertil Steril 2008; 89:281-300. [PMID: 18275883 PMCID: PMC2440710 DOI: 10.1016/j.fertnstert.2007.10.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Revised: 10/03/2007] [Accepted: 10/03/2007] [Indexed: 11/16/2022]
Abstract
The 2007 Summit on Environmental Challenges to Reproductive Health and Fertility convened scientists, health care professionals, community groups, political representatives, and the media to hear presentations on the impact of environmental contaminants on reproductive health and fertility, and to discuss opportunities to improve health through research, education, communication, and policy. Environmental reproductive health focuses on exposures to environmental contaminants, particularly during critical periods of development, and their potential effects on future reproductive health, including conception, fertility, pregnancy, adolescent development, and adult health. Approximately 87,000 chemical substances are registered for commercial use in the United States, with ubiquitous human exposures to environmental contaminants in air, water, food, and consumer products. Exposures during critical windows of susceptibility may result in adverse effects with lifelong and even intergenerational health impacts. Effects can include impaired development and function of the reproductive tract and permanently altered gene expression, leading to metabolic and hormonal disorders, reduced fertility and fecundity, and illnesses such as testicular, prostate, uterine, and cervical cancers later in life. This executive summary reviews effects of pre- and postnatal exposures on male and female reproductive health, and provides a series of recommendations for advancing the field in the areas of research, policy, health care, and community action.
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Affiliation(s)
- Tracey J Woodruff
- National Center of Excellence in Women's Health, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, California 94143, USA.
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182
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Guillette LJ, Edwards TM. Environmental influences on fertility: can we learn lessons from studies of wildlife? Fertil Steril 2008; 89:e21-4. [DOI: 10.1016/j.fertnstert.2007.12.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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183
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Katsu Y, Ichikawa R, Ikeuchi T, Kohno S, Guillette LJ, Iguchi T. Molecular cloning and characterization of estrogen, androgen, and progesterone nuclear receptors from a freshwater turtle (Pseudemys nelsoni). Endocrinology 2008; 149:161-73. [PMID: 17916628 PMCID: PMC2734501 DOI: 10.1210/en.2007-0938] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Accepted: 09/25/2007] [Indexed: 11/19/2022]
Abstract
Steroid hormones are essential for the normal function of many organ systems in vertebrates. Reproductive activity in females and males, such as the differentiation, growth, and maintenance of the reproductive system, requires signaling by the sex steroids. Although extensively studied in mammals and a few fish, amphibians, and bird species, the molecular mechanisms of sex steroid hormone (estrogens, androgens, and progestins) action are poorly understood in reptiles. Here we evaluate hormone receptor ligand interactions in a freshwater turtle, the red-belly slider (Pseudemys nelsoni), after the isolation of cDNAs encoding an estrogen receptor alpha (ERalpha), an androgen receptor (AR), and a progesterone receptor (PR). The full-length red-belly slider turtle (t)ERalpha, tAR, and tPR cDNAs were obtained using 5' and 3' rapid amplification cDNA ends. The deduced amino acid sequences showed high identity to the chicken orthologs (tERalpha, 90%; tAR, 71%; tPR, 71%). Using transient transfection assays of mammalian cells, tERalpha protein displayed estrogen-dependent activation of transcription from an estrogen-responsive element-containing promoter. The other receptor proteins, tAR and tPR, also displayed androgen- or progestin-dependent activation of transcription from androgen- and progestin-responsive murine mammary tumor virus promoters. We further examined the transactivation of tERalpha, tAR and tPR by ligands using a modified GAL4-transactivation system. We found that the GAL4-transactivation system was not suitable for the measurement of tAR and tPR transactivations. This is the first report of the full coding regions of a reptilian AR and PR and the examination of their transactivation by steroid hormones.
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Affiliation(s)
- Yoshinao Katsu
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
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184
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Katsu Y, Hinago M, Sone K, Urushitani H, Guillette LJ, Iguchi T. In vitro assessment of transcriptional activation of the estrogen and androgen receptors of mosquitofish, Gambusia affinis affinis. Mol Cell Endocrinol 2007; 276:10-7. [PMID: 17669586 DOI: 10.1016/j.mce.2007.06.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Revised: 06/11/2007] [Accepted: 06/18/2007] [Indexed: 11/22/2022]
Abstract
Sex-steroid hormones are essential for normal reproductive activity in both sexes. Estrogens are necessary for ovarian differentiation during a critical developmental stage in many vertebrates and promote the growth and differentiation of the female reproductive system. Androgens play essential roles in the development and functioning of the vertebrate male reproductive system as well as actively supporting spermatogenesis. Importantly, recent studies suggest that androgens and estrogens have important reproductive roles in both males and females. To understand the molecular mechanisms of estrogen and androgen actions and to evaluate estrogen and androgen receptor-ligand interactions in the mosquitofish, Gambusia affinis affinis, we used degenerate primer sets and PCR techniques to isolated DNA fragments encoding estrogen receptor alpha (ERalpha; ESR1), ERbeta1 (ERbeta1) and ERbeta2 from the ovary. Full-length mosquitofish ER (mfER) cDNAs were obtained using cDNA library screening and RACE techniques. Amino acid sequences of mfERs showed over-all homology of 46% (alpha versus beta1), 43% (alpha versus beta2), and 52% (beta1 versus beta2). We applied the ERE-luciferase reporter assay system to characterize these receptors. In this transient transfection assay system using mammalian cells, the mfER proteins displayed estrogen-dependent activation of transcription. In addition to ERs, the transactivation of mosquitofish ARs (mfARs) previously isolated by our group, were examined using an androgen-responsive MMTV-luciferase assay system. Mosquitofish ARs showed androgen-dependent activation of transcription from the MMTV promoter. These data provide a basic tool allowing future studies examining the receptor-ligand interactions and endocrine disrupting mechanisms in mosquitofish and also expands our knowledge of estrogen and androgen receptor evolution.
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Affiliation(s)
- Yoshinao Katsu
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan
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185
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Yamanaka H, Moriyoshi K, Ohmoto T, Ohe T, Sakai K. Degradation of bisphenol A by Bacillus pumilus isolated from kimchi, a traditionally fermented food. Appl Biochem Biotechnol 2007; 136:39-51. [PMID: 17416976 DOI: 10.1007/bf02685937] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Revised: 05/11/2006] [Accepted: 05/26/2006] [Indexed: 10/22/2022]
Abstract
Novel bisphenol A (BPA)-degrading bacterial strains, designated as BP-2CK, BP-21DK, and BP-22DK, were isolated from kimchi, a traditionally fermented food. These isolates were identified as Bacillus pumilus and efficiently degraded BPA in a medium supplemented with nutrients such as peptone, beef extract, and yeast extract. Strains BP-2CK, BP-21DK, and BP-22DK successfully degraded 25, 25, and 50 ppm of BPA, respectively, and all strains exhibited BPA-degrading activity in the presence of 10% NaCl. Accumulation of the metabolites including 4-hydroxyacetophenone, one of the intermediates produced by the other BPA-degrading bacteria, was not observed in BPA degradation by the isolated strains. These results indicate that the isolated food-derived bacteria are applicable for the construction of efficient and safer systems for the removal of BPA.
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Affiliation(s)
- Hayato Yamanaka
- Department of Environmental Technology, Osaka Municipal Technical Research Institute, 1-6-50, Morinomiya, Osaka, 536-8553, Japan.
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186
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Iguchi T, Watanabe H, Katsu Y. Toxicogenomics and ecotoxicogenomics for studying endocrine disruption and basic biology. Gen Comp Endocrinol 2007; 153:25-9. [PMID: 17324418 DOI: 10.1016/j.ygcen.2007.01.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 01/18/2007] [Accepted: 01/19/2007] [Indexed: 11/19/2022]
Abstract
Chemicals released into the environment have the potential to disrupt the endocrine system in wild animals, mouse, and humans. To understand molecular mechanisms of chemical toxicity in various species, toxicogenomics/ecotoxicogenomics, describing the integration of genomics (trascriptomics, proteomics and metabolomics) into toxicology/ecotoxicology, needs to be established as a powerful tool for research. Ecotoxicogenomics is defined as the study of gene and protein expression in non-target organisms that is important in responses to environmental toxicant exposures. Estrogen-responsive genes and estrogen response element(s) in genes have been identified in the mouse reproductive tract by application of cDNA microarray technology. Additionally, functional mechanisms of tributyltin action via nuclear receptors such as retinoid X receptor alpha and peroxisome proliferator activated receptor gamma also have been identified using cDNA microarray. A microarray system has been established for Daphnia magna. Toxicogenomics/ecotoxicogenomics provide powerful tools to help us understand not only molecular mechanisms of chemical toxicity but also the basic biology of various animal species.
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Affiliation(s)
- Taisen Iguchi
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan
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187
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Korhonen SP, Tuppurainen K, Asikainen A, Laatikainen R, Peräkylä M. SOMFA on Large Diverse Xenoestrogen Dataset: The Effect of Superposition Algorithms and External Regression Tools. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/qsar.200610003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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188
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Grün F, Blumberg B. Perturbed nuclear receptor signaling by environmental obesogens as emerging factors in the obesity crisis. Rev Endocr Metab Disord 2007; 8:161-71. [PMID: 17657605 DOI: 10.1007/s11154-007-9049-x] [Citation(s) in RCA: 220] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The modern world is plagued with expanding epidemics of diseases related to metabolic dysfunction. The factors that are driving obesity, diabetes, cardiovascular disease, hypertension, and dyslipidemias (collectively termed metabolic syndrome) are usually ascribed to a mismatch between the body's homeostatic nutrient requirements and dietary excess, coupled with insufficient exercise. The environmental obesogen hypothesis proposes that exposure to a toxic chemical burden is superimposed on these conditions to initiate or exacerbate the development of obesity and its associated health consequences. Recent studies have proposed a first set of candidate obesogens (diethylstilbestrol, bisphenol A, phthalates and organotins among others) that target nuclear hormone receptor signaling pathways (sex steroid, RXR-PPARgamma and GR) with relevance to adipocyte biology and the developmental origins of health and disease (DOHaD). Perturbed nuclear receptor signaling can alter adipocyte proliferation, differentiation or modulate systemic homeostatic controls, leading to long-term consequences that may be magnified if disruption occurs during sensitive periods during fetal or early childhood development.
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Affiliation(s)
- Felix Grün
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA, USA.
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189
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Prins GS, Birch L, Tang WY, Ho SM. Developmental estrogen exposures predispose to prostate carcinogenesis with aging. Reprod Toxicol 2007; 23:374-82. [PMID: 17123779 PMCID: PMC1927084 DOI: 10.1016/j.reprotox.2006.10.001] [Citation(s) in RCA: 183] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Revised: 10/07/2006] [Accepted: 10/10/2006] [Indexed: 11/28/2022]
Abstract
Prostate morphogenesis occurs in utero in humans and during the perinatal period in rodents. While largely driven by androgens, there is compelling evidence for a permanent influence of estrogens on prostatic development. If estrogenic exposures are abnormally high during the critical developmental period, permanent alterations in prostate morphology and function are observed, a process referred to as developmental estrogenization. Using the neonatal rodent as an animal model, it has been shown that early exposure to high doses of estradiol results in an increased incidence of prostatic lesions with aging which include hyperplasia, inflammatory cell infiltration and prostatic intraepithelial neoplasia or PIN, believed to be the precursor lesion for prostatic adenocarcinoma. The present review summarizes research performed in our laboratory to characterize developmental estrogenization and identify the molecular pathways involved in mediating this response. Furthermore, recent studies performed with low-dose estradiol exposures during development as well as exposures to environmentally relevant doses of the endocrine disruptor bisphenol A show increased susceptibility to PIN lesions with aging following additional adult exposure to estradiol. Gene methylation analysis revealed a potential epigenetic basis for the estrogen imprinting of the prostate gland. Taken together, our results suggest that a full range of estrogenic exposures during the postnatal critical period - from environmentally relevant bisphenol A exposure to low-dose and pharmacologic estradiol exposures - results in an increased incidence and susceptibility to neoplastic transformation of the prostate gland in the aging male which may provide a fetal basis for this adult disease.
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Affiliation(s)
- Gail S Prins
- Department of Urology, University of Illinois at Chicago, 820 South Wood Street, MC 955, Chicago, IL 60612, United States.
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190
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Crews D, Gore AC, Hsu TS, Dangleben NL, Spinetta M, Schallert T, Anway MD, Skinner MK. Transgenerational epigenetic imprints on mate preference. Proc Natl Acad Sci U S A 2007; 104:5942-6. [PMID: 17389367 PMCID: PMC1851596 DOI: 10.1073/pnas.0610410104] [Citation(s) in RCA: 275] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Environmental contamination by endocrine-disrupting chemicals (EDC) can have epigenetic effects (by DNA methylation) on the germ line and promote disease across subsequent generations. In natural populations, both sexes may encounter affected as well as unaffected individuals during the breeding season, and any diminution in attractiveness could compromise reproductive success. Here we examine mate preference in male and female rats whose progenitors had been treated with the antiandrogenic fungicide vinclozolin. This effect is sex-specific, and we demonstrate that females three generations removed from the exposure discriminate and prefer males who do not have a history of exposure, whereas similarly epigenetically imprinted males do not exhibit such a preference. The observations suggest that the consequences of EDCs are not just transgenerational but can be "transpopulational", because in many mammalian species, males are the dispersing sex. This result indicates that epigenetic transgenerational inheritance of EDC action represents an unappreciated force in sexual selection. Our observations provide direct experimental evidence for a role of epigenetics as a determinant factor in evolution.
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Affiliation(s)
| | - Andrea C. Gore
- Division of Pharmacology and Toxicology, and
- To whom correspondence should be addressed. E-mail:
| | | | | | - Michael Spinetta
- Department of Psychology, University of Texas, Austin, TX 78712; and
| | - Timothy Schallert
- Department of Psychology, University of Texas, Austin, TX 78712; and
| | - Matthew D. Anway
- Center for Reproductive Biology, School of Molecular Biosciences, Washington State University, Pullman, WA 99164-4231
| | - Michael K. Skinner
- Center for Reproductive Biology, School of Molecular Biosciences, Washington State University, Pullman, WA 99164-4231
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191
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Watanabe M, Yoshida R, Ueoka K, Aoki K, Sasagawa I, Hasegawa T, Sueoka K, Kamatani N, Yoshimura Y, Ogata T. Haplotype analysis of the estrogen receptor 1 gene in male genital and reproductive abnormalities. Hum Reprod 2007; 22:1279-84. [PMID: 17283037 DOI: 10.1093/humrep/del513] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND We have recently suggested that homozygosity for a specific 'AGATA' haplotype within a approximately 50 kb linkage disequilibrium (LD) block of the gene for estrogen receptor alpha (ESR1) may raise the susceptibility to cryptorchidism by enhancing estrogenic effects of environmental endocrine disruptors (EEDs). METHODS Haplotype analysis of ESR1 was performed in 328 Japanese subjects, i.e. 70 patients with micropenis (MP), 43 patients with hypospadias (HS), 80 patients with spermatogenic failure (SF) and 135 control males. Genotyping was performed by the 5' nuclease assay. RESULTS The LD block was identified in each of the patient groups and in the control males. The frequency of homozygotes for the specific 'AGATA' haplotype was markedly higher in the HS patients [P = 0.0000033, odds ratio [OR] = 11.26] and slightly higher in the MP patients (P = 0.034, OR = 3.64) than in the control males, and the 'AGATA' haplotype was strongly associated with HS (P = 0.0000022, OR = 11.26) and weakly associated with MP (P = 0.040, OR = 3.64) in a recessive mode. There was no significant difference between the SF patients and the control males. CONCLUSIONS Our results support the hypothesis that homozygosity for the specific ESR1 'AGATA' haplotype may increase the susceptibility to the development of male genital abnormalities in response to estrogenic EEDs.
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Affiliation(s)
- Masanori Watanabe
- Department of Endocrinology and Metabolism, National Research Institute for Child Health and Development, Tokyo, Japan
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192
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Brama M, Gnessi L, Basciani S, Cerulli N, Politi L, Spera G, Mariani S, Cherubini S, Scotto d'Abusco A, Scandurra R, Migliaccio S. Cadmium induces mitogenic signaling in breast cancer cell by an ERalpha-dependent mechanism. Mol Cell Endocrinol 2007; 264:102-8. [PMID: 17125913 DOI: 10.1016/j.mce.2006.10.013] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 10/12/2006] [Accepted: 10/13/2006] [Indexed: 11/23/2022]
Abstract
Breast cancer (BC) is linked to estrogen exposure. Estradiol (E2) stimulates BC cells proliferation by binding the estrogen receptor (ER). Hormone-related cancers have been linked to estrogenic environmental contaminants. Cadmium (Cd) a toxic pollutant, acts as estrogens in BC cells. Purpose of our study was to evaluate whether Cd regulates MCF-7 cell proliferation by activating ERK1/2, Akt and PDGFRalpha kinases. Cd increased cell proliferation and the ER-antagonist ICI 182,780 blunted it. To characterize an ER-dependent mechanism, ERalpha/beta expression was evaluated. Cd decreased ERalpha expression, but not ERbeta. Cd also increased ERK1/2, Akt and PDGFRalpha phosphorylation while ICI blocked it. Since stimulation of phosphorylation was slower than expected, c-fos and c-jun proto-oncogenes, and PDGFA were analyzed. Cd rapidly increased c-jun, c-fos and PDGFA expression. Cells were also co-incubated with the Cd and specific kinases inhibitors, which blocked the Cd-stimulated proliferation. In conclusion, our results indicate that Cd increases BC cell proliferation in vitro by stimulating Akt, ERK1/2 and PDGFRalpha kinases activity likely by activating c-fos, c-jun and PDGFA by an ERalpha-dependent mechanism.
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Affiliation(s)
- Marina Brama
- Department of Biochemical Sciences, University La Sapienza, P.le A.Moro 5, 00185 Roma, Italy
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193
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Habauzit D, Chopineau J, Roig B. SPR-based biosensors: a tool for biodetection of hormonal compounds. Anal Bioanal Chem 2006; 387:1215-23. [PMID: 17171560 DOI: 10.1007/s00216-006-0958-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Accepted: 10/19/2006] [Indexed: 10/23/2022]
Abstract
Novel cancer treatments, prevention of postmenopausal disorder, and prescription of oral contraceptives are the main developments in the design of synthetic estrogenic medication. The increasing consumption of these synthetic pharmaceuticals, in addition to human and animal natural estrogenic compound excretion, contribute to their environmental dissemination worldwide. Their assimilation as a result of consumption of food and water perturbs normal endocrine systems and leads to the emergence of human and animal diseases and malformations. These compounds are active in the organism at low concentrations. Accordingly, daily low-level exposure disrupts the natural equilibrium in the endocrine system. A method enabling quantification at such products at low levels (from pg L(-1) to ng L(-1)) is therefore required for these products. Surface plasmon resonance, essentially used for comprehension of molecular mechanisms and in drug discovery, can also be used for environmental pollutant monitoring. This technology has already been used for evaluation of the effects of chemical pollutants on specific nuclear receptors. It has been possible to determine the role of each individual compound on the disruption of the estrogen-activated cellular pathway. Development of SPR screening methods enables application of such an approach for quantification of these compounds in water.
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Affiliation(s)
- Denis Habauzit
- Centre LGEI, Ecole des Mines d'Alès, 6 avenue de Clavières, 30319 Alès Cedex, France
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194
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Yamada G, Suzuki K, Haraguchi R, Miyagawa S, Satoh Y, Kamimura M, Nakagata N, Kataoka H, Kuroiwa A, Chen Y. Molecular genetic cascades for external genitalia formation: an emerging organogenesis program. Dev Dyn 2006; 235:1738-52. [PMID: 16598715 DOI: 10.1002/dvdy.20807] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
External genitalia are anatomical structures located at the posterior embryonic region as part of several urogenital/reproductive organs. The embryonic anlage of the external genitalia, the genital tubercle (GT) develops as a bud-shaped structure with an initial urethral plate and later urethra. Embryonic external genitalia are considered to be one of the appendages. Recent experiments suggest that essential regulatory genes possess similar functions for the outgrowth regulation of the GT and limb appendages. The transient embryonic epithelia located in the distal GT are called the distal urethral epithelium (DUE) regulating, at least in part, the (distal) GT development. This review covers the available data about early patterning of GT and discusses the molecular developmental similarities and points of divergence between the different appendages. Development of the male and female external genitalia is also reviewed.
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Affiliation(s)
- G Yamada
- Center for Animal Resources and Development (CARD), Graduate School of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan.
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195
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Katsu Y, Kohno S, Oka T, Mitsui N, Tooi O, Santo N, Urushitani H, Fukumoto Y, Kuwabara K, Ashikaga K, Minami S, Kato S, Ohta Y, Guillette LJ, Iguchi T. Molecular cloning of estrogen receptor alpha (ERalpha; ESR1) of the Japanese giant salamander, Andrias japonicus. Mol Cell Endocrinol 2006; 257-258:84-94. [PMID: 16919388 DOI: 10.1016/j.mce.2006.07.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 07/11/2006] [Accepted: 07/13/2006] [Indexed: 11/16/2022]
Abstract
Estrogens are essential for normal reproductive activity in females and males and for ovarian differentiation during a critical developmental stage in many vertebrates. To understand the molecular mechanisms of estrogen action and to evaluate estrogen receptor ligand interactions in the Japanese giant salamander (Andrias japonicus), we isolated cDNA encoding the estrogen receptor (ER) from the liver. A full-length Japanese giant salamander ER cDNA (jgsER) was obtained using 5' and 3' rapid amplification cDNA ends (RACE). The deduced amino acid sequence of the jgsER showed high identity to the Xenopus ERalpha (ESR1) (77.7%). We have applied both the conventional ERE-luciferase reporter assay system and the GAL4-transactivation system to characterize this receptor. In two different transient transfection assay systems using mammalian cells, the jgsER protein displayed estrogen-dependent activation of transcription. The GAL4-transactivation system showed about 10-fold greater activity of the estrogen receptor by hormone when compared to the conventional ERE-luciferase reporter assay system. Tissue distribution of ERalpha mRNA was examined and kidney, ovary and liver exhibited expression. This is the first isolation of an estrogen receptor from a salamander and also is the first functional cDNA obtained from the Japanese giant salamander, an endangered species considered a special natural monument of Japan.
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Affiliation(s)
- Yoshinao Katsu
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Aichi, Japan
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196
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Kotomari S, Yoshikawa T, Mizutani T, Takagi H. N-Methylporphyrin as a Binding Motif for the Recognition of a Phenolic Hydroxy Group. CHEM LETT 2006. [DOI: 10.1246/cl.2006.1020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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197
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Xenobiotics with estrogen or antiandrogen action — disruptors of the male reproductive system. Open Med (Wars) 2006. [DOI: 10.2478/s11536-006-0027-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AbstractThe environmental and life-style changes associated with developing industry and agriculture, especially the exposure to endocrine disrupting chemicals (xenobiotics), are considered as causes of the increasing incidence of male reproductive system disorders. Most of the xenobiotics, which harmfully influence the male reproductive system, reveal estrogen-like (xenoestrogens) or anti-androgenic activity. Recent data have revealed physiological roles of estrogens in the male, however, there are evidences that estrogen-like substances may lead to many undesirable symptoms in the male i.e. gonadal dysgenesis, genital malformations, cryptorchidism, decreased fertility potential and testicular neoplastic changes. The number of xenoestrogens is still growing in the environment, whereas the mechanisms of their action are still not exactly known. They can be harmful not only to the present but potentially also to the next generations.
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Virgili F, Perozzi G. From phytoestrogens to obesity and the metabolic syndrome: Health from food and food for health. GENES & NUTRITION 2006; 1:137-9. [PMID: 18850208 PMCID: PMC3454836 DOI: 10.1007/bf02829962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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199
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Heyland A, Moroz LL. Cross-kingdom hormonal signaling: an insight from thyroid hormone functions in marine larvae. ACTA ACUST UNITED AC 2006; 208:4355-61. [PMID: 16339856 DOI: 10.1242/jeb.01877] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Thyroid hormones (THs) are small, lipophilic signaling molecules built from tyrosine and iodine. TH action is well characterized in vertebrates, where these molecules play a fundamental role as regulators of development, metabolism, growth and differentiation. Increasing evidence suggests that THs also function in a variety of invertebrate species. Two alternative sources of hormone for animals are exogenous (from food items) and endogenous synthesis. We propose that exogenous THs can convey environmental information as well as regulate metabolism, revealing new communication avenues between organisms from different kingdoms. While such modes of cross-kingdom communication have been previously considered for fatty acid-based signaling and steroid hormones in plant-animal interactions, this is the first attempt to explore such a mode of action for TH signaling. We suggest that exogenous sources of TH (from food) may have been ancestral, while the ability to synthesize TH endogenously may have evolved independently in a variety of metazoans, resulting in a diversity of signaling pathways and, possibly, morphological structures involved in TH-signaling.
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Affiliation(s)
- Andreas Heyland
- The Whitney Laboratory for Marine Bioscience and Department of Neuroscience, University of Florida, FL 32080, USA.
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200
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Ho SM, Tang WY, de Frausto JB, Prins GS. Developmental exposure to estradiol and bisphenol A increases susceptibility to prostate carcinogenesis and epigenetically regulates phosphodiesterase type 4 variant 4. Cancer Res 2006; 66:5624-32. [PMID: 16740699 PMCID: PMC2276876 DOI: 10.1158/0008-5472.can-06-0516] [Citation(s) in RCA: 527] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Early developmental perturbations have been linked to adult-onset prostate pathology, including excessive exposure to estrogenic compounds; however, the molecular basis for this imprinting event is not known. An important and controversial health concern is whether low-dose exposures to hormonally active environmental estrogens, such as bisphenol A, can promote human diseases, including prostate cancer. Here, we show that transient developmental exposure of rats to low, environmentally relevant doses of bisphenol A or estradiol increases prostate gland susceptibility to adult-onset precancerous lesions and hormonal carcinogenesis. We found permanent alterations in the DNA methylation patterns of multiple cell signaling genes, suggesting an epigenetic basis for estrogen imprinting. For phosphodiesterase type 4 variant 4 (PDE4D4), an enzyme responsible for cyclic AMP breakdown, a specific methylation cluster was identified in the 5'-flanking CpG island that was gradually hypermethylated with aging in normal prostates, resulting in loss of gene expression. Early and prolonged hypomethylation at this site following neonatal estradiol or bisphenol A exposure resulted in continued, elevated PDE4D4 expression. Cell line studies confirmed that site-specific methylation is involved in transcriptional silencing of the PDE4D4 gene and showed hypomethylation of this gene in prostate cancer cells. Importantly, the PDE4D4 alterations in the estrogen-exposed prostates were distinguishable before histopathologic changes of the gland, making PDE4D4 a candidate molecular marker for prostate cancer risk assessment as a result of endocrine disruptors. In total, these findings indicate that low-dose exposures to ubiquitous environmental estrogens affect the prostate epigenome during development and, in so doing, promote prostate disease with aging.
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Affiliation(s)
- Shuk-Mei Ho
- Department of Environmental Health, University of Cincinnati, Cincinnati, Ohio
| | - Wan-Yee Tang
- Department of Environmental Health, University of Cincinnati, Cincinnati, Ohio
| | | | - Gail S. Prins
- Department of Urology, University of Illinois at Chicago, Chicago, Illinois
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