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  1. Article ; Online: Targeted genome-wide methylation and gene expression analyses reveal signaling pathways involved in ovarian dysfunction after developmental EDC exposure in rats.

    Zama, Aparna Mahakali / Uzumcu, Mehmet

    Biology of reproduction

    2013  Volume 88, Issue 2, Page(s) 52

    Abstract: Transient exposure to methoxychlor (MXC), an environmental endocrine-disrupting chemical, during fetal and neonatal stages causes ovarian dysfunction in pubertal, adult, and aging animals. Adult animals have reduced number of ovulations and abnormal ... ...

    Abstract Transient exposure to methoxychlor (MXC), an environmental endocrine-disrupting chemical, during fetal and neonatal stages causes ovarian dysfunction in pubertal, adult, and aging animals. Adult animals have reduced number of ovulations and abnormal follicular composition associated with altered gene expression and DNA methylation patterns. To test the hypothesis that the ovarian epigenomic changes induced by MXC are detectable following the exposure period, leading to altered gene expression by adulthood, we conducted a targeted genome-wide methylation study using Nimblegen 3x720K CpG Island Plus RefSeq Promoter Arrays. Control (vehicle), low-dose MXC (20 μg/kg/day), or high-dose MXC (100 mg/kg/day) treatments were administered between Embryonic Day 19 and Postnatal Day (PND) 7. Ovaries were collected at PND 7 immediately after exposure or at adulthood, PND 60. Array hybridizations were conducted with genomic DNA after methylated DNA immunoprecipitation and the array data were analyzed. DNA methylation events were functionally annotated, and candidate loci common to all the treatments or unique to some treatments were identified. Specific loci encoding signaling molecules such as the regulatory subunit p85 of phosphoinositide-3-kinase, insulin-like growth factor-1 receptor, Harvey rat sarcoma viral oncogene, insulin receptor, and forkhead box protein O3 were identified to be hypermethylated in MXC-treated ovaries at PND 7 and/or PND 60. Examination of gene expression changes with TaqMan low-density arrays revealed that nearly 25% of the genes that were assayed were downregulated. These data demonstrate that key molecules in specific signaling pathways such as PTEN signaling, IGF-1 signaling, or rapid estrogen signaling are epigenetically altered in MXC-exposed ovaries, which is associated with ovarian dysfunction and female infertility.
    MeSH term(s) Animals ; DNA Methylation/drug effects ; DNA Methylation/genetics ; Dose-Response Relationship, Drug ; Endocrine Disruptors/pharmacology ; Female ; Genome/drug effects ; Genome/genetics ; Infertility, Female ; Methoxychlor/pharmacology ; Models, Animal ; Ovarian Follicle/drug effects ; Ovarian Follicle/physiopathology ; Ovary/drug effects ; Ovary/embryology ; Ovary/physiopathology ; Ovulation/drug effects ; Ovulation/physiology ; Pregnancy ; Prenatal Exposure Delayed Effects/physiopathology ; Rats ; Rats, Inbred F344 ; Signal Transduction/drug effects ; Signal Transduction/physiology ; Transcriptome/drug effects ; Transcriptome/genetics
    Chemical Substances Endocrine Disruptors ; Methoxychlor (RIA79UD69L)
    Language English
    Publishing date 2013-02-28
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1118-6
    ISSN 1529-7268 ; 0006-3363
    ISSN (online) 1529-7268
    ISSN 0006-3363
    DOI 10.1095/biolreprod.112.104802
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Coconut Oil Saturated Fatty Acids Improved Energy Homeostasis but not Blood Pressure or Cognition in VCD-Treated Female Mice.

    Sui, Ke / Yasrebi, Ali / Longoria, Candace R / MacDonell, Avery T / Jaffri, Zehra H / Martinez, Savannah A / Fisher, Samuel E / Malonza, Natasha / Jung, Katie / Tveter, Kevin M / Wiersielis, Kimberly R / Uzumcu, Mehmet / Shapses, Sue A / Campbell, Sara C / Roepke, Troy A / Roopchand, Diana E

    Endocrinology

    2023  Volume 164, Issue 3

    Abstract: Obesity, cardiometabolic disease, cognitive decline, and osteoporosis are symptoms of postmenopause, which can be modeled using 4-vinylcyclohexene diepoxide (VCD)-treated mice to induce ovarian failure and estrogen deficiency combined with high-fat diet ( ...

    Abstract Obesity, cardiometabolic disease, cognitive decline, and osteoporosis are symptoms of postmenopause, which can be modeled using 4-vinylcyclohexene diepoxide (VCD)-treated mice to induce ovarian failure and estrogen deficiency combined with high-fat diet (HFD) feeding. The trend of replacing saturated fatty acids (SFAs), for example coconut oil, with seed oils that are high in polyunsaturated fatty acids, specifically linoleic acid (LA), may induce inflammation and gut dysbiosis, and worsen symptoms of estrogen deficiency. To investigate this hypothesis, vehicle (Veh)- or VCD-treated C57BL/6J mice were fed a HFD (45% kcal fat) with a high LA:SFA ratio (22.5%: 8%), referred to as the 22.5% LA diet, or a HFD with a low LA:SFA ratio (1%: 31%), referred to as 1% LA diet, for a period of 23 to 25 weeks. Compared with VCD-treated mice fed the 22.5% LA diet, VCD-treated mice fed the 1% LA diet showed lower weight gain and improved glucose tolerance. However, VCD-treated mice fed the 1% LA diet had higher blood pressure and showed evidence of spatial cognitive impairment. Mice fed the 1% LA or 22.5% LA diets showed gut microbial taxa changes that have been associated with a mix of both beneficial and unfavorable cognitive and metabolic phenotypes. Overall, these data suggest that consuming different types of dietary fat from a variety of sources, without overemphasis on any particular type, is the optimal approach for promoting metabolic health regardless of estrogen status.
    MeSH term(s) Mice ; Female ; Animals ; Coconut Oil ; Mice, Inbred C57BL ; Dietary Fats/adverse effects ; Fatty Acids ; Diet, High-Fat/adverse effects ; Linoleic Acid ; Homeostasis ; Cognition ; Estrogens
    Chemical Substances Coconut Oil (Q9L0O73W7L) ; 4-vinyl-1-cyclohexene dioxide (596C064IG4) ; Dietary Fats ; Fatty Acids ; Linoleic Acid (9KJL21T0QJ) ; Estrogens
    Language English
    Publishing date 2023-01-10
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 427856-2
    ISSN 1945-7170 ; 0013-7227
    ISSN (online) 1945-7170
    ISSN 0013-7227
    DOI 10.1210/endocr/bqad001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Epigenetic effects of endocrine-disrupting chemicals on female reproduction: an ovarian perspective.

    Zama, Aparna Mahakali / Uzumcu, Mehmet

    Frontiers in neuroendocrinology

    2010  Volume 31, Issue 4, Page(s) 420–439

    Abstract: The link between in utero and neonatal exposure to environmental toxicants, such as endocrine-disrupting chemicals (EDCs) and adult female reproductive disorders is well established in both epidemiological and animal studies. Recent studies examining the ...

    Abstract The link between in utero and neonatal exposure to environmental toxicants, such as endocrine-disrupting chemicals (EDCs) and adult female reproductive disorders is well established in both epidemiological and animal studies. Recent studies examining the epigenetic mechanisms involved in mediating the effects of EDCs on female reproduction are gathering momentum. In this review, we describe the developmental processes that are susceptible to EDC exposures in female reproductive system, with a special emphasis on the ovary. We discuss studies with select EDCs that have been shown to have physiological and correlated epigenetic effects in the ovary, neuroendocrine system, and uterus. Importantly, EDCs that can directly target the ovary can alter epigenetic mechanisms in the oocyte, leading to transgenerational epigenetic effects. The potential mechanisms involved in such effects are also discussed.
    MeSH term(s) Animals ; Endocrine Disruptors/toxicity ; Environmental Pollutants/toxicity ; Epigenomics ; Female ; Gene Expression Profiling ; Genitalia, Female/drug effects ; Genitalia, Female/growth & development ; Humans ; Infertility, Female/chemically induced ; Infertility, Female/genetics ; Male ; Mice ; Neurosecretory Systems/drug effects ; Neurosecretory Systems/growth & development ; Ovary/drug effects ; Ovary/growth & development ; Receptors, Androgen/analysis ; Receptors, Estrogen/analysis ; Uterus/drug effects ; Uterus/growth & development
    Chemical Substances Endocrine Disruptors ; Environmental Pollutants ; Receptors, Androgen ; Receptors, Estrogen
    Language English
    Publishing date 2010-07-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 390985-2
    ISSN 1095-6808 ; 0532-7466 ; 0091-3022
    ISSN (online) 1095-6808
    ISSN 0532-7466 ; 0091-3022
    DOI 10.1016/j.yfrne.2010.06.003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Fetal and neonatal exposure to the endocrine disruptor methoxychlor causes epigenetic alterations in adult ovarian genes.

    Zama, Aparna Mahakali / Uzumcu, Mehmet

    Endocrinology

    2009  Volume 150, Issue 10, Page(s) 4681–4691

    Abstract: Exposure to endocrine-disrupting chemicals during development could alter the epigenetic programming of the genome and result in adult-onset disease. Methoxychlor (MXC) and its metabolites possess estrogenic, antiestrogenic, and antiandrogenic activities. ...

    Abstract Exposure to endocrine-disrupting chemicals during development could alter the epigenetic programming of the genome and result in adult-onset disease. Methoxychlor (MXC) and its metabolites possess estrogenic, antiestrogenic, and antiandrogenic activities. Previous studies showed that fetal/neonatal exposure to MXC caused adult ovarian dysfunction due to altered expression of key ovarian genes including estrogen receptor (ER)-beta, which was down-regulated, whereas ERalpha was unaffected. The objective of the current study was to evaluate changes in global and gene-specific methylation patterns in adult ovaries associated with the observed defects. Rats were exposed to MXC (20 microg/kgxd or 100 mg/kg.d) between embryonic d 19 and postnatal d 7. We performed DNA methylation analysis of the known promoters of ERalpha and ERbeta genes in postnatal d 50-60 ovaries using bisulfite sequencing and methylation-specific PCRs. Developmental exposure to MXC led to significant hypermethylation in the ERbeta promoter regions (P < 0.05), whereas the ERalpha promoter was unaffected. We assessed global DNA methylation changes using methylation-sensitive arbitrarily primed PCR and identified 10 genes that were hypermethylated in ovaries from exposed rats. To determine whether the MXC-induced methylation changes were associated with increased DNA methyltransferase (DNMT) levels, we measured the expression levels of Dnmt3a, Dnmt3b, and Dnmt3l using semiquantitative RT-PCR. Whereas Dnmt3a and Dnmt3l were unchanged, Dnmt3b expression was stimulated in ovaries of the 100 mg/kg MXC group (P < 0.05), suggesting that increased DNMT3B may cause DNA hypermethylation in the ovary. Overall, these data suggest that transient exposure to MXC during fetal and neonatal development affects adult ovarian function via altered methylation patterns.
    MeSH term(s) Animals ; Animals, Newborn ; DNA Methylation/drug effects ; DNA Modification Methylases/metabolism ; Down-Regulation ; Epigenesis, Genetic/drug effects ; Estrogen Receptor alpha/metabolism ; Estrogen Receptor beta/metabolism ; Female ; Methoxychlor/toxicity ; Ovary/drug effects ; Ovary/metabolism ; Pregnancy ; Prenatal Exposure Delayed Effects ; Promoter Regions, Genetic ; Rats ; Rats, Inbred F344 ; Up-Regulation
    Chemical Substances Estrogen Receptor alpha ; Estrogen Receptor beta ; DNA Modification Methylases (EC 2.1.1.-) ; Methoxychlor (RIA79UD69L)
    Language English
    Publishing date 2009-07-09
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 427856-2
    ISSN 1945-7170 ; 0013-7227
    ISSN (online) 1945-7170
    ISSN 0013-7227
    DOI 10.1210/en.2009-0499
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Methoxychlor and its metabolite HPTE inhibit cAMP production and expression of estrogen receptors α and β in the rat granulosa cell in vitro.

    Harvey, Craig N / Chen, Joseph C / Bagnell, Carol A / Uzumcu, Mehmet

    Reproductive toxicology (Elmsford, N.Y.)

    2015  Volume 51, Page(s) 72–78

    Abstract: The major metabolite of the estrogenic pesticide methoxychlor (MXC) HPTE is a stronger ESR1 agonist than MXC and acts also as an ESR2 antagonist. In granulosa cells (GCs), FSH stimulates estradiol via the second messenger cAMP. HPTE inhibits estradiol ... ...

    Abstract The major metabolite of the estrogenic pesticide methoxychlor (MXC) HPTE is a stronger ESR1 agonist than MXC and acts also as an ESR2 antagonist. In granulosa cells (GCs), FSH stimulates estradiol via the second messenger cAMP. HPTE inhibits estradiol biosynthesis, and this effect is greater in FSH-treated GCs than in cAMP-treated GCs. Therefore; we examined the effect of MXC/HPTE on FSH-stimulated cAMP production in cultured GCs. To test involvement of ESR-signaling, we used the ESR1 and ESR2 antagonist ICI 182,780, ESR2 selective antagonist PHTPP, and ESR2 selective agonist DPN. ESR1 and ESR2 mRNA and protein levels were quantified. Both HPTE and MXC inhibited the FSH-induced cAMP production. ICI 182,780 and PHTPP mimicked the inhibitory action of HPTE. MXC/HPTE reduced FSH-stimulated Esr2 mRNA and protein to basal levels. MXC/HPTE also inhibited FSH-stimulated Esr1. The greater inhibition on FSH-stimulated GCs is likely due to reduced cAMP level that involves ESR-signaling, through ESR2.
    MeSH term(s) Animals ; Cells, Cultured ; Cyclic AMP/metabolism ; Estradiol/analogs & derivatives ; Estradiol/pharmacology ; Estrogen Receptor Modulators/pharmacology ; Estrogen Receptor alpha/antagonists & inhibitors ; Estrogen Receptor alpha/genetics ; Estrogen Receptor beta/agonists ; Estrogen Receptor beta/antagonists & inhibitors ; Estrogen Receptor beta/genetics ; Estrogen Receptor beta/metabolism ; Female ; Follicle Stimulating Hormone/pharmacology ; Granulosa Cells/drug effects ; Granulosa Cells/metabolism ; Insecticides/pharmacology ; Methoxychlor/pharmacology ; Nitriles/pharmacology ; Phenols/pharmacology ; Pyrazoles/pharmacology ; Pyrimidines/pharmacology ; RNA, Messenger/metabolism ; Rats, Sprague-Dawley
    Chemical Substances 2,3-bis(4-hydroxyphenyl)-propionitrile ; 4-(2-phenyl-5,7-bis(trifluoromethyl)pyrazolo(1,5-a)pyrimidin-3-yl)phenol ; Estrogen Receptor Modulators ; Estrogen Receptor alpha ; Estrogen Receptor beta ; Insecticides ; Nitriles ; Phenols ; Pyrazoles ; Pyrimidines ; RNA, Messenger ; fulvestrant (22X328QOC4) ; Estradiol (4TI98Z838E) ; Follicle Stimulating Hormone (9002-68-0) ; Cyclic AMP (E0399OZS9N) ; 2,2-bis(4-hydroxyphenyl)-1,1,1-trichloroethane (H58165YO91) ; Methoxychlor (RIA79UD69L)
    Language English
    Publishing date 2015-01
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 639342-1
    ISSN 1873-1708 ; 0890-6238
    ISSN (online) 1873-1708
    ISSN 0890-6238
    DOI 10.1016/j.reprotox.2014.12.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Developmental exposure to environmental endocrine disruptors: consequences within the ovary and on female reproductive function.

    Uzumcu, Mehmet / Zachow, Rob

    Reproductive toxicology (Elmsford, N.Y.)

    2007  Volume 23, Issue 3, Page(s) 337–352

    Abstract: Female reproductive function depends upon the exquisite control of ovarian steroidogenesis that enables folliculogenesis, ovulation, and pregnancy. These mechanisms are set during fetal and/or neonatal development and undergo phases of differentiation ... ...

    Abstract Female reproductive function depends upon the exquisite control of ovarian steroidogenesis that enables folliculogenesis, ovulation, and pregnancy. These mechanisms are set during fetal and/or neonatal development and undergo phases of differentiation throughout pre- and post-pubescent life. Ovarian development and function are collectively regulated by a host of endogenous growth factors, cytokines, gonadotropins, and steroid hormones as well as exogenous factors such as nutrients and environmental agents. Endocrine disruptors represent one class of environmental agent that can impact female fertility by altering ovarian development and function, purportedly through estrogenic, anti-estrogenic, and/or anti-androgenic effects. This review discusses ovarian development and function and how these processes are affected by some of the known estrogenic and anti-androgenic endocrine disruptors. Recent information suggests not only that exposure to endocrine disruptors during the developmental period causes reproductive abnormalities in adult life but also that these abnormalities are transgenerational. This latter finding adds another level of importance for identifying and understanding the mechanisms of action of these agents.
    MeSH term(s) Animals ; Embryonic Development/drug effects ; Endocrine Disruptors/chemistry ; Endocrine Disruptors/poisoning ; Environmental Pollutants/chemistry ; Environmental Pollutants/poisoning ; Female ; Humans ; Ovary/drug effects ; Ovary/embryology ; Pregnancy ; Prenatal Exposure Delayed Effects ; Reproduction/drug effects ; Reproduction/physiology
    Chemical Substances Endocrine Disruptors ; Environmental Pollutants
    Language English
    Publishing date 2007-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 639342-1
    ISSN 1873-1708 ; 0890-6238
    ISSN (online) 1873-1708
    ISSN 0890-6238
    DOI 10.1016/j.reprotox.2006.10.006
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: The hepatocyte growth factor system as a regulator of female and male gonadal function.

    Zachow, Rob / Uzumcu, Mehmet

    The Journal of endocrinology

    2007  Volume 195, Issue 3, Page(s) 359–371

    Abstract: The hepatocyte growth factor (HGF) system comprises HGF, its receptor (the c-met tyrosine kinase), HGF activator (HGFA) protein, and HGFA inhibitor (HAI). The components of the HGF system have been identified in a plethora of tissues to include the ovary ...

    Abstract The hepatocyte growth factor (HGF) system comprises HGF, its receptor (the c-met tyrosine kinase), HGF activator (HGFA) protein, and HGFA inhibitor (HAI). The components of the HGF system have been identified in a plethora of tissues to include the ovary and testis. In its traditional context, the HGF system works via paracrine- and autocrine-mediated feedback in which HGF (of mesenchymal origin) binds and activates c-met (within epithelial cells); target cells then respond to HGF via any number of morphogenic and functional changes. The concomitant presence of HGFA and HAI suggests that HGF bioactivity can be locally modulated. A number of studies have collectively shown that the mammalian ovary and testis contain HGF, c-met, and HGFA; very little is currently known regarding HAI within the gonad. Within the ovary, HGF controls numerous key functions which collectively regulate the growth and differentiation of ovarian follicles; these include cell growth, steroidogenesis, and apoptosis within theca cells and/or granulosa cells. Comparatively, less is known about the function of HGF within the testicular Leydig and Sertoli cells, but evidence is emerging that HGF may regulate somatic cell function, including Leydig cell steroidogenesis. Changes in the cellular origin of HGF and c-met during fetal and postnatal testicular development suggest that HGF, in collaboration with other growth factors, may regulate important aspects of testicular cell morphogenesis and differentiation which enable male sexual viability. Likewise, experimental evidence showing that HGF can modulate many vital processes which enable ovarian follicle growth, differentiation, and function indicate the importance of HGF in female reproduction. This review presents what is currently known regarding the expression of the HGF system and its function within the ovary and testis.
    MeSH term(s) Animals ; Apoptosis/physiology ; Cell Division/physiology ; Female ; Gonadal Steroid Hormones/biosynthesis ; Granulosa Cells/cytology ; Granulosa Cells/physiology ; Hepatocyte Growth Factor/physiology ; Humans ; Leydig Cells/metabolism ; Male ; Ovarian Follicle/cytology ; Ovarian Follicle/growth & development ; Ovary/cytology ; Ovary/metabolism ; Ovary/physiology ; Testis/physiology ; Theca Cells/cytology ; Theca Cells/physiology
    Chemical Substances Gonadal Steroid Hormones ; Hepatocyte Growth Factor (67256-21-7)
    Language English
    Publishing date 2007-12
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 3028-4
    ISSN 1479-6805 ; 0022-0795
    ISSN (online) 1479-6805
    ISSN 0022-0795
    DOI 10.1677/JOE-07-0466
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  8. Article ; Online: Effects of ovariectomy and exercise training intensity on energy substrate and hepatic lipid metabolism, and spontaneous physical activity in mice.

    Tuazon, Marc A / Campbell, Sara C / Klein, Dylan J / Shapses, Sue A / Anacker, Keith R / Anthony, Tracy G / Uzumcu, Mehmet / Henderson, Gregory C

    Metabolism: clinical and experimental

    2018  Volume 83, Page(s) 234–244

    Abstract: Background: Menopause is associated with fatty liver, glucose dysregulation, increased body fat, and impaired bone quality. Previously, it was demonstrated that single sessions of high-intensity interval exercise (HIIE) are more effective than distance- ...

    Abstract Background: Menopause is associated with fatty liver, glucose dysregulation, increased body fat, and impaired bone quality. Previously, it was demonstrated that single sessions of high-intensity interval exercise (HIIE) are more effective than distance- and duration-matched continuous exercise (CE) on altering hepatic triglyceride (TG) metabolism and very-low density lipoprotein-TG (VLDL-TG) secretion.
    Methods: Six weeks training using these modalities was examined for effects on hepatic TG metabolism/secretion, glucose tolerance, body composition, and bone mineral density (BMD) in ovariectomized (OVX) and sham-operated (SHAM) mice. OVX and SHAM were assigned to distance- and duration-matched CE and HIIE, or sedentary control.
    Results: Energy expenditure during exercise was confirmed to be identical between CE and HIIE and both similarly reduced post-exercise absolute carbohydrate oxidation and spontaneous physical activity (SPA). OVX vs. SHAM displayed impaired glucose tolerance and greater body fat despite lower hepatic TG, and these outcomes were not affected by training. Only HIIE increased hepatic AMPK in OVX and SHAM, but neither training type impacted VLDL-TG secretion. As expected, BMD was lower in OVX, and training did not affect long bones.
    Conclusions: The results reveal intensity-dependent effects on hepatic AMPK expression and general exercise effects on subsequent SPA and substrate oxidation that is independent of estrogen status. These findings support the notion that HIIE can impact aspects of liver physiology in females while the effects of exercise on whole body substrate selection appear to be independent of training intensity. However, neither exercise approach mitigated the impairment in glucose tolerance and elevated body fat occurring in OVX mice.
    MeSH term(s) Animals ; Energy Metabolism/physiology ; Estrogens/deficiency ; Estrogens/pharmacology ; Female ; Lipid Metabolism/physiology ; Liver/metabolism ; Mice ; Mice, Inbred C57BL ; Motor Activity/physiology ; Ovariectomy/adverse effects ; Physical Conditioning, Animal/methods ; Physical Conditioning, Animal/physiology
    Chemical Substances Estrogens
    Language English
    Publishing date 2018-03-06
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80230-x
    ISSN 1532-8600 ; 0026-0495
    ISSN (online) 1532-8600
    ISSN 0026-0495
    DOI 10.1016/j.metabol.2018.02.011
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  9. Article: The methoxychlor metabolite, 2,2-bis-(p-hydroxyphenyl)-1,1,1-trichloroethane, inhibits steroidogenesis in rat ovarian granulosa cells in vitro.

    Zachow, Rob / Uzumcu, Mehmet

    Reproductive toxicology (Elmsford, N.Y.)

    2006  Volume 22, Issue 4, Page(s) 659–665

    Abstract: The exquisitely balanced hormonal mechanisms that control female fertility can be affected by several internal and external factors including pathogens, genetic maladies, and environmental agents. In the latter group are natural and synthetic agents ... ...

    Abstract The exquisitely balanced hormonal mechanisms that control female fertility can be affected by several internal and external factors including pathogens, genetic maladies, and environmental agents. In the latter group are natural and synthetic agents known as endocrine disruptors. One such compound, 2,2-bis-(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), is the predominant metabolite of the pesticide methoxychlor. The effects of HPTE on ovarian steroidogenesis have not been previously reported and were investigated in the present study. Granulosa cells harvested from immature rats were treated with follicle-stimulating hormone (FSH) or N(6),2'-O-dibutyryladenosine 3',5'-cyclic monophosphate (db-cAMP) in the presence or absence of HPTE. After 48h, progesterone (P4) and estradiol-17beta (E2) concentrations were measured in the culture media. Steady-state levels of the mRNAs encoding steroidogenic acute regulatory protein (StAR), P450 side-chain cleavage (P450scc), 3beta-hydroxysteroid dehydrogenase type 1 (3beta-HSD), and P450 aromatase (P450arom) were examined using real-time PCR. Both FSH- and db-cAMP-stimulated P(4) accumulation were impaired by HPTE. In contrast, FSH-, but not db-cAMP-stimulated, E2 content was suppressed by HPTE. The FSH-dependent increase in the abundance of P450scc, 3beta-HSD, and P450arom mRNAs was blocked by HPTE; however, StAR expression was not altered. Although db-cAMP-dependent P450arom was moderately reduced by HPTE, the levels of db-cAMP-dependent StAR, P450scc, and 3beta-HSD mRNAs were increased in the presence of HPTE. These data collectively show that HPTE can disrupt P4 and E2 production in granulosa cells, with implications for sites of action both preceding and following the generation of cAMP. The steroid-modulatory effects of HPTE in granulosa cells appear to involve the general suppression of the FSH-dependent expression of mRNAs encoding steroid pathway proteins, whereas the disparate effects of HPTE on cAMP-dependent mRNA content in this regard suggest a broader and more complex mechanism of action.
    MeSH term(s) 3-Hydroxysteroid Dehydrogenases/genetics ; Animals ; Aromatase/genetics ; Cells, Cultured ; Cyclic CMP/analogs & derivatives ; Cyclic CMP/pharmacology ; Estradiol/biosynthesis ; Female ; Follicle Stimulating Hormone/pharmacology ; Granulosa Cells/cytology ; Granulosa Cells/drug effects ; Granulosa Cells/metabolism ; Methoxychlor/metabolism ; Phenols/metabolism ; Phenols/toxicity ; Phosphoproteins/genetics ; Progesterone/biosynthesis ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Up-Regulation/drug effects ; Up-Regulation/genetics
    Chemical Substances Phenols ; Phosphoproteins ; RNA, Messenger ; steroidogenic acute regulatory protein ; Cyclic CMP (3616-08-8) ; Progesterone (4G7DS2Q64Y) ; Estradiol (4TI98Z838E) ; dibutyryl cyclic-3',5'-cytidine monophosphate (64649-87-2) ; Follicle Stimulating Hormone (9002-68-0) ; 3-Hydroxysteroid Dehydrogenases (EC 1.1.-) ; 3 beta-hydroxy-delta 5-steroid dehydrogenase, rat (EC 1.1.1.51) ; Aromatase (EC 1.14.14.1) ; 2,2-bis(4-hydroxyphenyl)-1,1,1-trichloroethane (H58165YO91) ; Methoxychlor (RIA79UD69L)
    Language English
    Publishing date 2006-11
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 639342-1
    ISSN 1873-1708 ; 0890-6238
    ISSN (online) 1873-1708
    ISSN 0890-6238
    DOI 10.1016/j.reprotox.2006.04.018
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  10. Article ; Online: Fetal and neonatal exposure to the endocrine disruptor, methoxychlor, reduces lean body mass and bone mineral density and increases cortical porosity.

    Fagnant, Heather S / Uzumcu, Mehmet / Buckendahl, Patricia / Dunn, Michael G / Shupper, Peter / Shapses, Sue A

    Calcified tissue international

    2014  Volume 95, Issue 6, Page(s) 521–529

    Abstract: Endogenous estrogen has beneficial effects on mature bone and negatively affects the developing skeleton, whereas the effect of environmental estrogens is not known. Methoxychlor (MXC) is a synthetic estrogen known as a persistent organochlorine and used ...

    Abstract Endogenous estrogen has beneficial effects on mature bone and negatively affects the developing skeleton, whereas the effect of environmental estrogens is not known. Methoxychlor (MXC) is a synthetic estrogen known as a persistent organochlorine and used as a pesticide. Methoxychlor and its metabolites display estrogenic, anti-estrogenic and anti-androgenic activity and may therefore influence bone. Fifty-eight male fetal and neonatal rats were exposed to either: a negative control (DMSO), 0.020, 100 mg/kg MXC, or 1 mg/kg β-estradiol-3-benzoate (EB; positive control). Rats were treated daily for 11 days, from embryonic day 19 to postnatal day (PND) 7 or for 4 days during the postnatal period (PND 0-7). All rats were analyzed at PND-84. Total body, femur, spine, and tibia areal bone mineral density (BMD) and content (BMC), lean body mass (LBM) and fat were measured by dual energy X-ray absorptiometry. Bone geometry and volumetric (v) BMD were measured using micro-computed tomography and biomechanical properties using three-point bending were assessed. Rats exposed to EB or MXC (at either the high and/or low dose), independent of exposure interval showed lower body weight, LBM, tibia and femur BMD and length, and total body BMD and BMC than DMSO control group (p ≤ 0.05). Methoxychlor and EB exposure increased cortical porosity compared to DMSO controls. Trabecular vBMD, number and separation, and cortical polar moment of inertia and cross-sectional area were lower due to EB exposure compared to control (p < 0.05). Early MXC exposure compromises cortical porosity and bone size at maturity, and could ultimately increase the risk of fracture with aging.
    MeSH term(s) Absorptiometry, Photon ; Animals ; Animals, Newborn ; Body Composition/drug effects ; Bone Density/drug effects ; Bone and Bones/drug effects ; Female ; Fetus ; Insecticides/toxicity ; Male ; Methoxychlor/toxicity ; Pregnancy ; Prenatal Exposure Delayed Effects/pathology ; Rats ; Rats, Inbred F344
    Chemical Substances Insecticides ; Methoxychlor (RIA79UD69L)
    Language English
    Publishing date 2014-12
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 304266-2
    ISSN 1432-0827 ; 0944-0747 ; 0008-0594 ; 0171-967X
    ISSN (online) 1432-0827
    ISSN 0944-0747 ; 0008-0594 ; 0171-967X
    DOI 10.1007/s00223-014-9916-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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