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1.
Med Sci Monit ; 23: 5041-5048, 2017 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-29056745

RESUMEN

BACKGROUND The aim of this study was to evaluate changes in sex hormone metabolism in patients with threatened miscarriage. MATERIAL AND METHODS We recruited 73 women in early pregnancy (6-8 weeks of gestation) and divided them into the following 2 groups based on whether they had vaginal bleeding: group A (n=34), the threatened abortion group; and group B (n=39), the normal pregnancy group. Human chorionic gonadotrophin (hCG), estradiol (E2), progesterone (P4), and testosterone (T) serum levels were tested and sex hormone metabolites in the urine were detected using gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). As the control, data for sex hormones and their metabolites were obtained in normal women of childbearing age without pregnancy (group C: n=23). RESULTS E2 and T serum levels were lower in women with threatened miscarriage (group A). Estrone (E1), E2, estriol (E3), 16α-hydroxyestrone (16α-OHE1), 4-methoxyestrone (4-MeOE1), 2-hydroxyestradiol (2-OHE2), and 4-methoxyestradiol (4-MeOE2) levels were significantly lower in group A (P=0.001, 0.003, 0.009, 0.001, 0.012, 0.032, and 0.047, respectively.). Urine levels of dehydroepiandrosterone (DHEA), androstenedione (A2), and the metabolite of (A2) were also significantly lower in group A (P=0.007, 0.009, and 0.011, respectively). The 2-OHE1/E1, 4-OHE1/E1, 2-MeOE1/E1, and 2-MeOE2/E2 ratios were lower in group B, whereas the 2-OHE2/E2, 4-OHE2/E2, and 4-MeOE2/E2 ratios were dramatically lower in all pregnant women (groups A and B) than in group C. CONCLUSIONS Deficiency in DHEA and abnormal levels of sex hormone metabolites may cause a reduction in the activity of estrogens in women with threatened abortion. These alterations may result in bleeding during the first trimester of pregnancy.


Asunto(s)
Amenaza de Aborto/metabolismo , Hormonas Esteroides Gonadales/análisis , Hormonas Esteroides Gonadales/metabolismo , Amenaza de Aborto/fisiopatología , Adulto , Gonadotropina Coriónica/análisis , Gonadotropina Coriónica/sangre , Estradiol/análisis , Estradiol/sangre , Estrógenos/análogos & derivados , Estrógenos/análisis , Femenino , Hormonas Esteroides Gonadales/orina , Humanos , Hidroxiestronas/análisis , Hidroxiestronas/sangre , Embarazo , Progesterona/análisis , Progesterona/sangre , Espectrometría de Masas en Tándem/métodos , Testosterona/análisis , Testosterona/sangre
3.
Br J Nutr ; 113(9): 1384-95, 2015 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-25850566

RESUMEN

The objective of the present study was to find the optimum dose of flaxseed that would decrease PG and alter oestrogen pathway endpoints implicated in ovarian cancer. In the study, four groups of fifty 1.5-year-old chickens were fed different amounts of flaxseed (0, 5, 10 or 15% of their total diet) for 4 months and were then killed to collect blood and tissues. Levels of flaxseed lignan metabolites, Enterolactone (EL) and Enterodiol (ED) were measured in the serum, liver and ovaries by liquid chromatography-MS/MS, and n-3 and n-6 fatty acid (FA) levels were measured by GC. The effects of the varied flaxseed doses were assessed by measuring levels of PGE2 and oestrogen metabolites (16-hydroxyestrone (16-OHE1) and 2-hydroxyestrone (2-OHE1)) as well as by analysing the expression of the oestradiol metabolising enzymes CYP3A4 (cytochrome p450, family 3, subfamily A, polypeptide 4), CYP1B1 (cytochrome p450, family 1, subfamily B, polypeptide 1) and CYP1A1 (cytochrome p450, family 1, subfamily A, polypeptide 1) and that of oestrogen receptor α (ERα) in the ovaries. The ratio of n-3:n-FA increased with an increase in flaxseed supplementation and corresponded to a dose-dependent decrease in cyclo-oxygenase-2 protein and PGE2 levels. EL and ED increased in the serum, liver and ovaries with increased concentrations of flaxseed. Flaxseed decreased the expression of ERα in the ovaries. The ratio of 2-OHE1:16-OHE1 in the serum increased significantly in the 15% flaxseed diet, and there was a corresponding increase in CYP1A1 in the liver and decrease in CYP3A4 in the ovaries. CYP1B1 mRNA also decreased with flaxseed diet in the ovaries. The 15% flaxseed-supplemented diet significantly decreased inflammatory PGE2, ERα, CYP3A4, CYP1B1 and 16-OHE1, but it increased CYP1A1 and 2-OHE1, which thus reduced the inflammatory and pro-carcinogenic micro-environment of the ovaries.


Asunto(s)
Anticarcinógenos/administración & dosificación , Pollos , Dieta/veterinaria , Lino , Neoplasias Ováricas/prevención & control , Ovario/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , 4-Butirolactona/sangre , Animales , Ciclooxigenasa 1/análisis , Ciclooxigenasa 1/genética , Ciclooxigenasa 2/análisis , Ciclooxigenasa 2/genética , Citocromo P-450 CYP1A1/análisis , Citocromo P-450 CYP1B1/análisis , Citocromo P-450 CYP3A/análisis , Suplementos Dietéticos , Dinoprostona/análisis , Receptor alfa de Estrógeno/análisis , Estrógenos/metabolismo , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-6/análisis , Femenino , Hidroxiestronas/análisis , Lignanos/análisis , Lignanos/sangre , Lignanos/metabolismo , Hígado/química , Ovario/química , ARN Mensajero/análisis
4.
J AOAC Int ; 91(1): 237-46, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18376603

RESUMEN

This paper presents an analytical method applied to the determination of 3 natural steroid hormones, estrone, 17 beta-estradiol, and 16 alpha-hydroxyestrone, and the contraceptive estrogen, 17 alpha-ethynylestradiol, at the sub-ng/L level in water samples [surface water and wastewater treatment plant (WWTP) samples]. The solid-phase extraction conditions were optimized using C18 cartridges. Identification and quantification were performed using a column liquid chromatographic/tandem mass spectrometric system with electrospray ionization in the negative mode. Before analyzing steroids in complex matrixes, statistical tools permitted a fine validation of the analytical method, and performance was evaluated for spring water in terms of recovery, specificity, trueness, repeatability, and intralaboratory reproducibility. The results showed the accuracy of the method, and limits of detection (LOD) ranged between 0.02 and 0.21 ng/L. The determination of steroids in WWTP effluents, which contain high levels of organic matter, required an additional purification step on silica cartridges. The high efficiency of the purification was proved with LOD < 0.3 ng/L from 200 mL sample. Specificity of the entire analytical procedure was shown by repeatable recoveries at low and high levels of the calibration range.


Asunto(s)
Cromatografía Liquida/métodos , Estradiol/análisis , Etinilestradiol/análisis , Hidroxiestronas/análisis , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisis
5.
Obstet Gynecol ; 108(6): 1439-47, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17138778

RESUMEN

OBJECTIVE: The catechol-O-methyltransferase enzyme catalyzes the methylation of the catechol estrogens, 2- or 4-hydroxyestrogen, to 2- or 4-methoxyestrogen. Both the hydroxy estrogens and methoxy estrogens were shown to modulate the effects of estrogen. Because catechol-O-methyltransferase activity controls levels of these metabolites, it may help regulate the cellular estrogenic milieu. In this study, we examined the regulation of catechol-O-methyltransferase expression in human myometrial cells. METHODS: Catechol-O-methyltransferase expression was assessed by reverse transcription-polymerase chain reaction, Western blot, and luciferase assays in human myometrial cells after treatment with estrogen or progesterone. Catechol-O-methyltransferase expression was measured in cells after treatment with tumor necrosis factor alpha (TNFalpha) alone or with lactacystin, a proteasome inhibitor. Luciferase assays were also conducted using human myometrial cells containing an estrogen response element-luciferase reporter gene to measure levels of estrogen-mediated transactivation after treatment with estrogen and increasing concentrations of 2-hydroxestrogen. RESULTS: Catechol-O-methyltransferase expression was down-regulated by progesterone or estrogen. Tumor necrosis factor alpha upregulated catechol-O-methyltransferase expression, whereas cotreatment with lactacystin attenuated this response, suggesting that TNFalpha activated nuclear factor kappa B to induce catechol-O-methyltransferase expression. Increased concentrations of 2-hydroxyestrogen attenuated estrogen-mediated transcription in the myometrial cells. CONCLUSION: Catechol-O-methyltransferase expression may be regulated in the myometrium to control the local action of estrogen. Low levels of catechol-O-methyltransferase in the myometrium would result in an accumulation of 2-hydroxyestrogen and may antagonize the local effect of estrogen. High levels of catechol-O-methyltransferase in the myometrium would result in lower levels of 2-hydroxyestrogen and may increase sensitivity to estrogen.


Asunto(s)
Catecol O-Metiltransferasa/análisis , Miometrio/enzimología , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacología , Western Blotting , Células Cultivadas , Regulación hacia Abajo , Estrógenos/farmacología , Femenino , Genes Reporteros , Humanos , Hidroxiestronas/análisis , Luciferasas/análisis , Miometrio/citología , Progesterona/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Activación Transcripcional , Factor de Necrosis Tumoral alfa/farmacología , Regulación hacia Arriba
6.
Clin Cancer Res ; 8(10): 3146-55, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12374682

RESUMEN

PURPOSE: The main goal of our study was to assess estrogen contents of breast tumor tissues, having different estrogen receptor status, in relation to long-term follow-up of patients. EXPERIMENTAL DESIGN: Twenty-one breast cancer cases, all collected from January 1986 to January 1988 at the M. Ascoli Cancer Hospital Centre in Palermo, were included in the study and compared with 6 healthy women as a control group. Average follow-up time of patients was 144 +/- 10 months. The estrogen receptor status of tissues was determined by both ligand binding and immunohistochemical assays. A high performance liquid chromatography-based approach, jointly with gas chromatography/mass spectrometry, was used to identify and measure main estrogens, various hydroxyestrogens, and their methoxy derivatives in both normal and tumor tissues. RESULTS: Although variable concentrations of hydroxylated estrogens were detected, they consistently accounted for >80% of all of the estrogens. Significantly greater amounts of both 2- and 4-hydroxyestradiol, along with a marked increase of 16 alpha-hydroxyestrone (OHE(1)), were observed in cancer with respect to normal breast tissues. A significant positive association was observed with elevated 16 alpha OHE(1) (P = 0.015) in patients alive, leading to significantly lower (P = 0.043) 2OHE(1):16 alpha OHE(1) ratio values. Conversely, ratio values of 4:2 hydroxy+methoxy estrogens was significantly lower (P = 0.006) in deceased patients. Using cutoff values of 1.2 for 4:2 hydroxy+methoxy ratio and 150 fmol/mg tissue for 16 alpha OHE(1) we achieved a clear-cut separation of patients, with over-cutoff patients having 147 months and under cutoff patients showing only 47 months median survival time (P = 0.00008). CONCLUSIONS: Our data imply that individual hydroxyestrogens may have a distinct role in the onset and the clinical progression of breast cancer, with greater 16 alpha OHE(1) levels being in turn associated to cancer with respect to normal tissues and to a prolonged survival of breast cancer patients.


Asunto(s)
Neoplasias de la Mama/química , Neoplasias de la Mama/mortalidad , Estradiol/análogos & derivados , Estradiol/análisis , Hidroxiestronas/análisis , Adulto , Anciano , Sitios de Unión , Cromatografía Líquida de Alta Presión , Estrógenos/análisis , Estrógenos de Catecol , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Receptores de Estrógenos/metabolismo , Tasa de Supervivencia
7.
Acta Pharmacol Sin ; 22(4): 369-74, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11742592

RESUMEN

AIM: To constitute a method to determine the estradiol metabolites in human liver microsome in low concentration of estradiol. METHODS: Use high performance liquid chromatography after solvent extraction, evaporation, and reconstitution to separate the metabolites and use a electrochemistry detector to detect the metabolites. RESULTS: With a mobile phase of acetic acid buffer-acetonitrile (50:50, v/v, pH 4.5) at flow rate of 1.0 mL/min and a potential of +0.7 V vs Ag/AgCl, all six composition were well separated and satisfactorily detected. There are E3, 16alpha-OHE1, 2-OHE2, E1, and two unidentified composition. The minimum detectable amount is about 100 p g on column. This method is sensitive enough to detect E1 in a substrate concentration of 1 micromol/L. CONCLUSION: The method can be used to study the metabolism mechanism of estradiol in liver microsome.


Asunto(s)
Estradiol/análogos & derivados , Estradiol/metabolismo , Estriol/análisis , Hidroxiestronas/análisis , Microsomas Hepáticos/metabolismo , Adulto , Cromatografía Líquida de Alta Presión/métodos , Estradiol/análisis , Estrona/análisis , Humanos , Microsomas Hepáticos/química
9.
Chem Pharm Bull (Tokyo) ; 37(6): 1561-3, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2776239

RESUMEN

Antigenic complexes of 2-hydroxyestrone (2-OHE1) were obtained by Mannich reaction of 2-OHE1 and bovine serum albumin (BSA) and by coupling of 2-OHE1 1-glutathione thioether to BSA using glutaraldehyde. Antiserum raised against the antigen obtained by the Mannich reaction had high affinity (Kd = 3.8 x 10(9) M-1) and relatively high specificity; cross reactivities for estrone, 4-hydroxyestrone and 2-methoxyestrone were 2.1%, 10% and 1.5%, respectively. The other antiserum also had high affinity (4.5 x 10(9) M-1) but its cross reactivities for the above three steroids were more than 100%. Concentrations of 2-hydroxyestrone in human plasma were determined by radioimmunoassay with the more specific antiserum and Sephadex LH-20 chromatography to be less than a minimum detectable amount (less than 10 pg/ml) (men), 20.9 pg/ml (women, proliferation) and 26.0 pg/ml (women, periovulation).


Asunto(s)
Estrona/análogos & derivados , Hidroxiestronas/análisis , Adulto , Animales , Reacciones Cruzadas , Femenino , Humanos , Hidroxiestronas/inmunología , Masculino , Conejos , Radioinmunoensayo
10.
J Steroid Biochem ; 32(6): 873-885, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2755132

RESUMEN

Certain previously unrecognized ligands of SHBG of low polarity in pregnancy were identified. They include two weakly bound compounds: 5 alpha-pregnane-3,20-dione and progesterone; and two strongly bound substances, 2-methoxyestrone and a new steroid, estradienolone (17 beta-hydroxy-1,5-estradiene-3-one). The identification of the first three peaks was based on chromatographic elution patterns, binding characteristics and gas chromatography-mass spectrometry. The identification of the fourth peak, the new steroid, was based on similar kinds of evidence and, in addition, solubility characteristics and ultraviolet absorption spectrum.


Asunto(s)
Embarazo/sangre , Globulina de Unión a Hormona Sexual/análisis , 5-alfa-Dihidroprogesterona , Cromatografía Líquida de Alta Presión , Estrenos/análisis , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hidrocortisona/análisis , Hidroxiestronas/análisis , Inicio del Trabajo de Parto , Nandrolona/análisis , Pregnanodionas/análisis , Progesterona/análisis
11.
Hoppe Seylers Z Physiol Chem ; 363(7): 737-44, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6290363

RESUMEN

The synthesis, purification and structural confirmation of the 6-(carboxymethoxyimino) derivatives of 2-methoxyestrone and 2-methoxyestradiol-17 beta are described. These derivatives were coupled to bovine serum albumin by the mixed anhydride method, and rabbits were immunized with the product. The resulting antisera showed high affinity and specificity for 2-methoxyestrone and 2-methoxyestradiol-17 beta, respectively, with low cross reactivities to structurally related estrogens.


Asunto(s)
Estradiol/análogos & derivados , Estrógenos Conjugados (USP)/síntesis química , Estrona/análogos & derivados , Hidroxiestronas/análisis , Sueros Inmunes , 2-Metoxiestradiol , Animales , Bovinos , Reacciones Cruzadas , Estradiol/análisis , Estradiol/inmunología , Hidroxiestronas/inmunología , Indicadores y Reactivos , Conejos/inmunología , Radioinmunoensayo , Albúmina Sérica Bovina
14.
Science ; 197(4304): 657-9, 1977 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-877577

RESUMEN

Catechol estrogens have been identified and measured in rat brain and various endocrine tissues with the use of a sensitive radioenzymatic assay. The specificity of this assay was confirmed by thin-layer chromatography and mass spectral analysis of the reaction products. The concentration of catechol estrogens in the hypothalamus and pituitary are at least ten times higher than reported previously for the parent estrogens. Catechol estrogens have potent endocrine effects and, because of their normal occurrence in the hypothalamic-pituitary axis, they have an important role in neuroendocrine regulation.


Asunto(s)
Química Encefálica , Estrógenos/análisis , Hipotálamo/análisis , Hipófisis/análisis , Animales , Castración , Estradiol/análogos & derivados , Estradiol/análisis , Femenino , Hidroxiestronas/análisis , Hígado/análisis , Ovario/análisis , Ratas
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