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Carrasco-Ruiz Á, Sánchez-García O, Pacheco P, Martínez-Gómez M, Cuevas-Romero E, Castelán F. Differential estrogen-related responses in myofiber cross-sectional area of pelvic floor muscles in female rats. Gynecol Endocrinol 2021; 37:528-533. [PMID: 33501865 DOI: 10.1080/09513590.2021.1875427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To determine the role of estrogens in myofiber cross-sectional area (CSA) of the pubococcyegeus (Pcm) and iliococcygeus muscles (Icm). METHODS In Experiment 1, we excised the Pcm and Icm during the metestrus and proestrus stages of the estrous cycle to measure the myofiber CSA. In Experiment 2, we allocated other rats into the following groups: sham (Sh), ovariectomized (OVX), OVX plus 1,4,6-androstatriene-3,17-dione (ATD; OVX + ATD), an aromatase inhibitor, and OVX plus estradiol benzoate (OVX + EB). We carried out appropriate statistical tests to determine significant differences (p ≤ 0.05) in variables measured for both Experiments. RESULTS The Pcm myofiber CSA at proestrus was higher than at metestrus, while the Icm myofiber CSA did not change. Ovariectomy increased the Pcm myofiber CSA, which was exacerbated with the ATD administration. The EB supplementation successfully reversed the ovariectomy-induced enlargement of the CSA. No significant changes were detected for the Icm myofiber CSA. CONCLUSIONS Fluctuating ovarian steroid levels at the estrus cycle significantly influence the CSA myofiber of the Pcm but not that of the Icm. Estrogen actions, having a gonadal or extragonadal origin, influence importantly the CSA of the Pcm.
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Affiliation(s)
- Ángeles Carrasco-Ruiz
- Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Tlaxcala, México
| | - Octavio Sánchez-García
- Programa Educativo de Química Clínica, Facultad de Ciencias de la Salud, Universidad Autónoma de Tlaxcala, Tlaxcala, México
| | - Pablo Pacheco
- Instituto de Neuroetología, Universidad Veracruzana, Xalapa, Mexico
- Depto. de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tlaxcala, México
| | - Margarita Martínez-Gómez
- Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Tlaxcala, México
- Depto. de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tlaxcala, México
| | - Estela Cuevas-Romero
- Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Tlaxcala, México
| | - Francisco Castelán
- Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Tlaxcala, México
- Depto. de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tlaxcala, México
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Kinetic Study of 17α-Estradiol Activity in Comparison with 17β-Estradiol and 17α-Ethynylestradiol. Catalysts 2021. [DOI: 10.3390/catal11050634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
17α-estradiol (αE2), an endogenous stereoisomer of the hormone 17β-estradiol (E2), is capable of binding to estrogen receptors (ER). We aimed to mathematically describe, using experimental data, the possible interactions between αE2 and sperm ER during the process of sperm capacitation and to develop a kinetic model. The goal was to compare the suggested kinetic model with previously published results of ER interactions with E2 and 17α-ethynylestradiol (EE2). The HPLC-MS/MS method was developed to monitor the changes of αE2 concentration during capacitation. The calculated relative concentrations Bt were used for kinetic analysis. Rate constants k and molar ratio n were optimized and used for the construction of theoretical B(t) curves. Modifications in αE2–ER interactions were discovered during comparison with models for E2 and EE2. These new interactions displayed autocatalytic formation of an unstable adduct between the hormone and the cytoplasmic receptors. αE2 accumulates between the plasma membrane lipid bilayer with increasing potential, and when the critical level is reached, αE2 penetrates through the inner layer of the plasma membrane into the cytoplasm. It then rapidly reacts with the ER and creates an unstable adduct. The revealed dynamics of αE2–ER action may contribute to understanding tissue rejuvenation and the cancer-related physiology of αE2 signaling.
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Ahn KH, Kim HY, Cho GJ, Hong SC, Oh MJ, Kim HJ. Role of sex hormones in cervical changes in a cervical excision-related preterm delivery mouse model. J OBSTET GYNAECOL 2020; 41:138-146. [PMID: 32157933 DOI: 10.1080/01443615.2020.1727868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Progesterone and oestrogen play important roles during parturition; however, their roles in the uterine cervix during preterm labour and delivery are unknown. We evaluated the serum progesterone and oestrogen levels and changes in their receptors (PR and ER) in the cervix in a cervical excision-associated preterm delivery mouse model. Adult female C57BL/6 mice were divided into four groups: sham, cervical excision (Ex), lipopolysaccharide (LPS) and Ex + LPS. Mating was permitted at 3 weeks post-Ex. On gestation day 16, mice were administered LPS intrauterine (100 µg/100 µL/mouse) or physiological saline (100 µL) via laparotomy. Uterine cervices and blood were sampled immediately postpartum. As a result, epithelial PR and muscular ERα were down- and upregulated, respectively, in the proximal cervix in Ex + LPS group compared to in the sham group. These results indicate that unique sex hormone effects are exerted on the uterine cervix during cervical excision-associated spontaneous preterm labour and delivery.Impact statementWhat is already known on this subject? Preterm and term parturition require the withdrawal of progesterone and the activation of oestrogen in the uterine body and systemic levels. However, we have little understanding of the role of the sex hormones in the uterine cervix.What do the results of this study add? Increased ERα-to-PR expression ratio in the proximal cervix was associated with preterm labour and delivery. ERα expression in the smooth muscle layer of the proximal cervix was higher and PR expression in the proximal cervix epithelium was lower during preterm labour and delivery.What are the implications of these findings for clinical practice and/or further research? This study revealed the differences between the roles of sex hormones and their receptors in epithelial and muscle layers of proximal and distal cervices in preterm labour and delivery.
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Affiliation(s)
- Ki Hoon Ahn
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Seoul, South Korea
| | - Hee Youn Kim
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Seoul, South Korea
| | - Geum Joon Cho
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Seoul, South Korea
| | - Soon Cheol Hong
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Seoul, South Korea
| | - Min Jeong Oh
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Seoul, South Korea
| | - Hai Joong Kim
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Seoul, South Korea
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Chen J, Khalil RA. Matrix Metalloproteinases in Normal Pregnancy and Preeclampsia. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 148:87-165. [PMID: 28662830 PMCID: PMC5548443 DOI: 10.1016/bs.pmbts.2017.04.001] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Normal pregnancy is associated with marked hemodynamic and uterine changes that allow adequate uteroplacental blood flow and uterine expansion for the growing fetus. These pregnancy-associated changes involve significant uteroplacental and vascular remodeling. Matrix metalloproteinases (MMPs) are important regulators of vascular and uterine remodeling. Increases in MMP-2 and MMP-9 have been implicated in vasodilation, placentation, and uterine expansion during normal pregnancy. The increases in MMPs could be induced by the increased production of estrogen and progesterone during pregnancy. MMP expression/activity may be altered during complications of pregnancy. Decreased vascular MMP-2 and MMP-9 may lead to decreased vasodilation, increased vasoconstriction, hypertensive pregnancy, and preeclampsia. Abnormal expression of uteroplacental integrins, cytokines, and MMPs may lead to decreased maternal tolerance, apoptosis of invasive trophoblast cells, inadequate remodeling of spiral arteries, and reduced uterine perfusion pressure (RUPP). RUPP may cause imbalance between the antiangiogenic factors soluble fms-like tyrosine kinase-1 and soluble endoglin and the proangiogenic vascular endothelial growth factor and placental growth factor, or stimulate the release of inflammatory cytokines, hypoxia-inducible factor, reactive oxygen species, and angiotensin AT1 receptor agonistic autoantibodies. These circulating factors could target MMPs in the extracellular matrix as well as endothelial and vascular smooth muscle cells, causing generalized vascular dysfunction, increased vasoconstriction and hypertension in pregnancy. MMP activity can also be altered by endogenous tissue inhibitors of metalloproteinases (TIMPs) and changes in the MMP/TIMP ratio. In addition to their vascular effects, decreases in expression/activity of MMP-2 and MMP-9 in the uterus could impede uterine growth and expansion and lead to premature labor. Understanding the role of MMPs in uteroplacental and vascular remodeling and function could help design new approaches for prediction and management of preeclampsia and premature labor.
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Affiliation(s)
- Juanjuan Chen
- Vascular Surgery Research Laboratories, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, United States
| | - Raouf A Khalil
- Vascular Surgery Research Laboratories, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, United States.
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Bafor EE, Ebidame VO, Elvis-Offiah UB, Omoruyi O, Eze GI, Igbinuwen O, Braimoh KP. A role of alpha-tocopherol and phylloquinone in the modulation of uterine contractility and reproductive function in mouse models. Medicina (B Aires) 2017; 53:190-202. [DOI: 10.1016/j.medici.2017.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 04/05/2017] [Accepted: 05/08/2017] [Indexed: 10/19/2022] Open
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Hill M, Dušková M, Stárka L. Dehydroepiandrosterone, its metabolites and ion channels. J Steroid Biochem Mol Biol 2015; 145:293-314. [PMID: 24846830 DOI: 10.1016/j.jsbmb.2014.05.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 05/06/2014] [Accepted: 05/11/2014] [Indexed: 11/20/2022]
Abstract
This review is focused on the physiological and pathophysiological relevance of steroids influencing the activities of the central and peripheral nervous systems with regard to their concentrations in body fluids and tissues in various stages of human life like the fetal development or pregnancy. The data summarized in this review shows that DHEA and its unconjugated and sulfated metabolites are physiologically and pathophysiologically relevant in modulating numerous ion channels and participate in vital functions of the human organism. DHEA and its unconjugated and sulfated metabolites including 5α/β-reduced androstane steroids participate in various physiological and pathophysiological processes like the management of GnRH cyclic release, regulation of glandular and neurotransmitter secretions, maintenance of glucose homeostasis on one hand and insulin insensitivity on the other hand, control of skeletal muscle and smooth muscle activities including vasoregulation, promotion of tolerance to ischemia and other neuroprotective effects. In respect of prevalence of steroid sulfates over unconjugated steroids in the periphery and the opposite situation in the CNS, the sulfated androgens and androgen metabolites reach relevance in peripheral organs. The unconjugated androgens and estrogens are relevant in periphery and so much the more in the CNS due to higher concentrations of most unconjugated steroids in the CNS tissues than in circulation and peripheral organs. This article is part of a Special Issue entitled "Essential role of DHEA".
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Affiliation(s)
- M Hill
- Steroid Hormone Unit, Institute of Endocrinology, Národní třída 8, Prague 116 94, Praha 1, CZ 116 94, Czech Republic.
| | - M Dušková
- Steroid Hormone Unit, Institute of Endocrinology, Národní třída 8, Prague 116 94, Praha 1, CZ 116 94, Czech Republic.
| | - L Stárka
- Steroid Hormone Unit, Institute of Endocrinology, Národní třída 8, Prague 116 94, Praha 1, CZ 116 94, Czech Republic.
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7
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Dang Y, Li W, Tran V, Khalil RA. EMMPRIN-mediated induction of uterine and vascular matrix metalloproteinases during pregnancy and in response to estrogen and progesterone. Biochem Pharmacol 2013; 86:734-47. [PMID: 23856290 DOI: 10.1016/j.bcp.2013.06.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/19/2013] [Accepted: 06/27/2013] [Indexed: 11/26/2022]
Abstract
Pregnancy is associated with uteroplacental and vascular remodeling in order to adapt for the growing fetus and the hemodynamic changes in the maternal circulation. We have previously shown upregulation of uterine matrix metalloproteinases (MMPs) during pregnancy. Whether pregnancy-associated changes in MMPs are localized to the uterus or are generalized in feto-placental and maternal circulation is unclear. Also, the mechanisms causing the changes in uteroplacental and vascular MMPs during pregnancy are unclear. MMPs expression, activity and tissue distribution were measured in uterus, placenta and aorta of virgin, mid-pregnant (mid-Preg) and late pregnant (late-Preg) rats. Western blots and gelatin zymography revealed increases in MMP-2 and -9 in uterus and aorta of late-Preg compared with virgin and mid-Preg rats. In contrast, MMP-2 and -9 were decreased in placenta of late-Preg versus mid-Preg rats. Extracellular MMP inducer (EMMPRIN) was increased in uterus and aorta of pregnant rats, but was less in placenta of late-Preg than mid-Preg rats. Prolonged treatment of uterus or aorta of virgin rats with 17β-estradiol and progesterone increased the amount of EMMPRIN, MMP-2 and -9, and the sex hormone-induced increases in MMPs were prevented by EMMPRIN neutralizing antibody. Immunohistochemistry revealed that MMP-2 and -9 and EMMPRIN increased in uterus and aorta of pregnant rats, but decreased in placenta of late-Preg versus mid-Preg rats. Thus pregnancy-associated upregulation of uterine MMPs is paralleled by increased vascular MMPs, and both are mediated by EMMPRIN and induced by estrogen and progesterone, suggesting similar role of MMPs in uterine and vascular tissue remodeling and function during pregnancy. The decreased MMPs and EMMPRIN in placenta of late-Preg rats suggests reduced role of MMPs in feto-placental circulation during late pregnancy.
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Affiliation(s)
- Yiping Dang
- Vascular Surgery Research Laboratory, Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Yin Z, Sada AA, Reslan OM, Narula N, Khalil RA. Increased MMPs expression and decreased contraction in the rat myometrium during pregnancy and in response to prolonged stretch and sex hormones. Am J Physiol Endocrinol Metab 2012; 303:E55-70. [PMID: 22496348 PMCID: PMC3404560 DOI: 10.1152/ajpendo.00553.2011] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Normal pregnancy is associated with uterine relaxation to accommodate the stretch imposed by the growing fetus; however, the mechanisms underlying the relationship between pregnancy-associated uterine stretch and uterine relaxation are unclear. We hypothesized that increased uterine stretch during pregnancy is associated with upregulation of matrix metalloproteinases (MMPs), which in turn cause inhibition of myometrium contraction and promote uterine relaxation. Uteri from virgin, midpregnant (day 12), and late-pregnant rats (day 19) were isolated, and myometrium strips were prepared for measurement of isometric contraction and MMP expression and activity using RT-PCR, Western blot analysis, and gelatin zymography. Oxytocin caused concentration-dependent contraction of myometrium strips that was reduced in mid- and late-pregnant rats compared with virgin rats. Pretreatment with the MMP inhibitors SB-3CT (MMP-2/MMP-9 Inhibitor IV), BB-94 (batimastat), or Ro-28-2653 (cipemastat) enhanced contraction in myometrium of pregnant rats. RT-PCR, Western blot analysis, and gelatin zymography demonstrated increased mRNA expression, protein amount, and activity of MMP-2 and MMP-9 in myometrium of late-pregnant>midpregnant>virgin rats. Prolonged stretch of myometrium strips of virgin rats under 8 g basal tension for 18 h was associated with reduced contraction and enhanced expression and activity of MMP-2 and MMP-9, which were reversed by MMP inhibitors. Concomitant treatment of stretched myometrium of virgin rats with 17β-estradiol (E2), progesterone (P4), or E2+P4 was associated with further reduction in contraction and increased MMP expression and activity. MMP-2 and MMP-9 caused significant reduction of oxytocin-induced contraction of myometrium of virgin rat. Thus, normal pregnancy is associated with reduced myometrium contraction and increased MMPs expression and activity. The results are consistent with the possibility that myometrium stretch and concomitant increase in sex hormones during pregnancy are associated with increased expression/activity of specific MMPs, which in turn inhibit uterine contraction and promote uterine relaxation.
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Affiliation(s)
- Zongzhi Yin
- Vascular Surgery Research Laboratory, Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, Boston, MA, USA
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Ayan D, Roy J, Maltais R, Poirier D. Impact of estradiol structural modifications (18-methyl and/or 17-hydroxy inversion of configuration) on the in vitro and in vivo estrogenic activity. J Steroid Biochem Mol Biol 2011; 127:324-30. [PMID: 21827856 DOI: 10.1016/j.jsbmb.2011.07.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 07/15/2011] [Accepted: 07/26/2011] [Indexed: 12/14/2022]
Abstract
It is well recognized that the majority of breast cancers are initially hormone-dependent and that 17β-estradiol (17β-E2) plays a crucial role in their development and progression. For this reason, using a compound able to block a specific enzyme involved in the last steps of the biosynthesis of 17β-E2 remains a rational way to treat estrogen-dependent diseases such as breast cancer. The present study describes the biological in vitro and in vivo evaluation of a structural modification (inversion of C18-methyl group at position 13 from β to α face) of 17β-E2 (1) and 17α-estradiol (17α-E2; 2). The two epimers 18-epi-17β-E2 (3) and 18-epi-17α-E2 (4) were obtained in two chemical steps by inversion of the C18-methyl of estrone using 1,2-phenylendiamine in refluxing acetic acid and reduction of ketone at position C17 with LiAlH(4). The new E2 isomers were tested on estrogen-sensitive cell lines (MCF-7 and T-47D), on estrogen-sensitive tissues (uterus and vagina of mice) and on estrogen receptor (ER) to determine their estrogenic potency relatively to natural estrogen 17β-E2 (1). The results show that 18-epi-17β-E2 (3) possesses the lower affinity for ER (RBA = 1.2%), the lower estrogenicity on estrogen-sensitive cells (1000 folds less estrogenic than 17β-E2 in MCF-7) and no uterotrophic (estrogenic) activity when tested on mice. In fact, we observed the following order of estrogenicity: 18-epi-17β-E2 (3)<18-epi-17α-E2 (4) << 17α-E2 (2)17β-E2 (1). These results suggest that the inversion of C18-methyl of natural 17β-E2 scaffold could be a useful strategy to decrease the estrogenicity of E2 derivatives used as enzyme inhibitors in the context of a treatment of estrogen-dependent diseases.
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Affiliation(s)
- Diana Ayan
- Laboratory of Medicinal Chemistry, CHUQ, CHUL-Research Center, Endocrinology and Genomic Unit, and Laval University, Faculty of Medicine, Quebec, Quebec G1V 4G2, Canada
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Bafor E, Sanni U. Uterine contractile effects of the aqueous and ethanol leaf extracts of Newbouldia Laevis (Bignoniaceae) in vitro. Indian J Pharm Sci 2011; 71:124-7. [PMID: 20336206 PMCID: PMC2839394 DOI: 10.4103/0250-474x.54274] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 12/04/2008] [Accepted: 03/15/2009] [Indexed: 11/04/2022] Open
Abstract
Based on traditional reports, the aqueous and ethanol extracts of the leaves of N. laevis were tested on isolated uterine preparations of non-pregnant rats. The effects of increasing cumulative concentrations of the extracts on the amplitude and frequency of spontaneously contracting uterine tissues were tested. Direct effects of the extracts and acetylcholine on uterine smooth muscle were also tested in organ baths containing aerated physiological salt solution maintained at 37 degrees . The EC(50) and Emax were determined and analyzed using one way ANOVA with Dunnett's post hoc test. The extract significantly increased the frequency (P<0.05) of spontaneous contractions without significantly affecting the amplitude. The extracts and acetylcholine were observed to directly stimulate uterine contractions, however there were significant differences (P<0.05) in their EC(50) and Emax. In conclusion, the leaves of N. laevis increase the frequency of spontaneously contracting tissues and directly stimulate uterine contractions which may account for the use of the leaf extract traditionally.
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Affiliation(s)
- E Bafor
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Benin, 300 001, Nigeria
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Prokai-Tatrai K, Bonds D, Prokai L. Simultaneous Measurement of 17β-Estradiol, 17α-Estradiol and Estrone by GC-Isotope Dilution MS/MS. Chromatographia 2010; 71:311-315. [PMID: 20625535 PMCID: PMC2901118 DOI: 10.1365/s10337-009-1441-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A convenient GC-MS/MS-based method was developed for the simultaneous measurement of 17β-estradiol, 17α-estradiol and estrone using liquid-liquid extraction, a single-step derivatization with N-(trimethylsilyl)imidazole and the corresponding deuterated estrogens as internal standards. Separation of these estrogens was achieved on a 50% phenyl polysilphenylene-siloxane bonded phase column. MS/MS response factors for the derivatized analytes and their corresponding internal standards were found to be practically identical. Therefore, analyte concentrations could be determined by multiplying the measured analyte to internal standard ion-current ratio with known molar concentration of the corresponding deuterated internal standards. Assay accuracies, determined from the analyses of quality control samples obtained by spiking known concentrations of analytes into charcoal-stripped human serum, were in the -11% to +14% range. Limits of quantitations were between 13 pg/mL and 21 pg/mL from this biological medium.
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Affiliation(s)
- Katalin Prokai-Tatrai
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA;
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
| | - Darius Bonds
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA;
| | - Laszlo Prokai
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA;
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E. Bafor E, Omogbai EK, I. Ozolua R. Evaluation of the Uterotonic Activity of the Aqueous Leaf Extract of Ficus exasperata Vahl (Moraceae). ACTA ACUST UNITED AC 2009. [DOI: 10.3923/rjmp.2009.34.40] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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13
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Wray S, Noble K. Sex hormones and excitation-contraction coupling in the uterus: the effects of oestrous and hormones. J Neuroendocrinol 2008; 20:451-61. [PMID: 18266942 DOI: 10.1111/j.1365-2826.2008.01665.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this review, we examine how far the increased understanding that we have of the events in excitation contraction can explain the effects of the oestrous cycle and sex hormones on uterine function. Observational studies of electrical and mechanical activity in the rat myometrium have shown a relative quiescence during pro-oestrous, with little propagation of any electrical events. Thus, uterine activity can be said to approximately inversely reflect plasma 17beta-oestradiol concentrations. We show that Ca(2+) signalling and mechanical activity are greatest in metoestrous and dioestrous compared to pro-oestrous and oestrous. These data are discussed in terms of hormonal effects on Ca(2+) and K(+) channels. Finally, the influence of sex hormones on lipid rafts and caveolae are considered and discussed in relation to recent findings on their role in uterine signalling and contractility, and cholesterol levels and obesity.
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Affiliation(s)
- S Wray
- The Physiological Department, School of Biomedical Sciences, University of Liverpool, Liverpool, UK.
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Hutchins SR, White MV, Hudson FM, Fine DD. Analysis of lagoon samples from different concentrated animal feeding operations for estrogens and estrogen conjugates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:738-44. [PMID: 17328177 DOI: 10.1021/es062234+] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Although Concentrated Animal Feeding Operations (CAFOs) have been identified as potentially important sources for the release of estrogens into the environment, information is lacking on the concentrations of estrogens in whole lagoon effluents (including suspended solids) which are used for land application. Lagoons associated with swine, poultry, and cattle operations were sampled at three locations each for direct analysis for estrogens by GC/ MS/MS and estrogen conjugates by LC/MS/MS. Estrogen conjugates were also analyzed indirectly by first subjecting the same samples to enzyme hydrolysis. Solids from centrifuged samples were extracted for free estrogens to estimate total estrogen load. Total free estrogen levels (estrone, 17alpha-estradiol, 17beta-estradiol, estriol) were generally higher in swine primary (1000-21000 ng/L), followed by poultry primary (1800-4000 ng/L), dairy secondary (370-550 ng/L), and beef secondary (22-24 ng/L) whole lagoon samples. Swine and poultry lagoons contained levels of 17(alpha-estradiol comparable to those of 17beta-estradiol. Confirmed estrogen conjugates included estrone-3-sulfate (2-91 ng/L), 17beta-estradiol-3-sulfate (8-44 ng/L), 17alpha-estradiol-3-sulfate (141-182 ng/L), and 17beta-estradiol-17-sulfate (72-84 ng/L) in some lagoons. Enzymatic hydrolysis indicated the presence of additional unidentified estrogen conjugates not detected bythe LC/MS/MS method. In most cases estrogen conjugates accounted for at least a third of the total estrogen equivalents. Collectively, these methods can be used to better determine estrogen loads from CAFO operations, and this research shows that estrogen conjugates contribute significantly to the overall estrogen load, even in different types of CAFO lagoons.
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Affiliation(s)
- Stephen R Hutchins
- Ground Water and Ecosystems Restoration Division, National Risk Management Research Laboratory, U.S. Environmental Protection Agency, P.O. Box 1198, Ada, Oklahoma 74821-1198, USA.
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