Read by QxMD icon Read

Glucuronidase estrogen

Elias Baydoun, Atia-Tul Wahab, Nayab Shoaib, Malik Shoaib Ahmad, Roula Abdel-Massih, Colin Smith, Nimra Naveed, M Iqbal Choudhary
Biotransformation of a steroidal contraceptive drug, etonogestrel (1), (13-ethyl-17β-hydroxy-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3-one) was investigated with Cunninghamella blakesleeana and C. echinulata. Five metabolites 2-6 were obtained on incubation of 1 with Cunninghamella blakesleeana, and three metabolites, 2, 4, and 6 were isolated from the transformation of 1 with C. echinulata. Among them, metabolites 2-4 were identified as new compounds. Their structures were deduced as 6β-hydroxy-11,22-epoxy-etonogestrel (2), 11,22-epoxy-etonogestrel (3), 10β-hydroxy-etonogestrel (4), 6β-hydroxy-etonogestrel (5), and 14α-hydroxy-etonogestrel (6)...
November 2016: Steroids
Monika Drastikova, Martin Beranek, Filip Gabalec, David Netuka, Vaclav Masopust, Tomas Cesak, Josef Marek, Vladimir Palicka, Jan Cap
AIMS: Pituitary adenomas (PA) are non-invasive benign tumors with a high autopsy prevalence. They are classified according to the type of hormone secreted (prolactin, growth hormone, adrenocorticotropin, thyrotropin, folitropin, or luteinizing hormone). Clinically non-functioning adenomas (CNFA) lacking the typical hypersecretion of hormones make up a significant portion of PA. The aim of the study was to determine the complete expression profiles of somatostatin receptors (SSTR1-SSTR5), dopamine receptors type 2 (D2R), and estrogen receptors (ER1) in various types of PA...
June 2016: Biomedical Papers of the Medical Faculty of the University Palacký, Olomouc, Czechoslovakia
Masato Okano, Mitsuhiko Sato, Asami Kojima, Shinji Kageyama
Mepitiostane (2α,3α-epithio-17β-(1-methoxycyclopentyloxy)-5α-androstane), which is a prodrug of epitiostanol (2α,3α-epitio-5α-androstane-17β-ol), is an epitiosteroid having anti-estrogenic and weak androgenic anabolic activities. The World Anti-Doping Agency prohibits the misuse of mepitiostane by athletes. Detection of the urinary metabolites epitiostanol sulfoxide and epitiostanol was studied using liquid chromatography/mass spectrometry (LC-MS) for doping control purposes. The use of LC-MS provided advantages over gas chromatography/mass spectrometry for detecting heat labile steroids because epitiostanol and epitiostanol sulfoxide were primarily pyrolized to 5α-androst-2-en-17β-ol...
November 10, 2015: Journal of Pharmaceutical and Biomedical Analysis
Oihana Ros, Josu Aguirre, Ailette Prieto, Maitane Olivares, Nestor Etxebarria, Asier Vallejo
This study describes a new method for the simultaneous extraction and enzymatic hydrolysis of alkylphenols, estrogens, bisphenol-A and phthalate metabolite (mono-2-ethylhexyl ester, MEHP) in fish bile using polyethersulfone (PES) polymer as sorptive material. Parameters affecting the hydrolysis (enzyme amount) and extraction (nature of polymeric material, PES desorption solvent nature and time, PES amount and time profile) were optimised. The optimum conditions were fixed as: 5 PES tubes (1.5 cm length × 0...
September 2015: Analytical and Bioanalytical Chemistry
Alicia Romero-Lorca, Apolonia Novillo, María Gaibar, Fernando Bandrés, Ana Fernández-Santander
Tamoxifen is used to prevent and treat estrogen-dependent breast cancer. It is described as a prodrug since most of its antiestrogen effects are exerted through its hydroxylated metabolites 4-OH-tamoxifen and endoxifen. In prior work, we correlated optimal plasma levels of these metabolites with certain genotypes of CYP2D6 and SULT1A2. This descriptive study examines correlations between concentrations of tamoxifen's glucuronide metabolites and genotypes UGT1A4 Pro24Thr, UGT1A4 Leu48Val, UGT2B7 His268Tyr, UGT2B15 Asp85YTyr UGT2B15 Lys523Thr and UGT2B17del in 132 patients with estrogen receptor-positive breast cancer under treatment with tamoxifen...
2015: PloS One
L P Madhubhani P Hemachandra, Hitisha Patel, R Esala P Chandrasena, Jaewoo Choi, Sujeewa C Piyankarage, Shuai Wang, Yijin Wang, Emily N Thayer, Robert A Scism, Bradley T Michalsen, Rui Xiong, Marton I Siklos, Judy L Bolton, Gregory R J Thatcher
The risk of developing hormone-dependent cancers with long-term exposure to estrogens is attributed both to proliferative, hormonal actions at the estrogen receptor (ER) and to chemical carcinogenesis elicited by genotoxic, oxidative estrogen metabolites. Nontumorigenic MCF-10A human breast epithelial cells are classified as ER(-) and undergo estrogen-induced malignant transformation. Selective estrogen receptor modulators (SERM), in use for breast cancer chemoprevention and for postmenopausal osteoporosis, were observed to inhibit malignant transformation, as measured by anchorage-independent colony growth...
May 2014: Cancer Prevention Research
Fangqing Zhou, Lin Zhang, Ai Liu, Yang Shen, Jinpeng Yuan, Xiaojin Yu, Xu Feng, Qian Xu, Chuange Cheng
A method was established for the determination of three phenolic environmental estrogens, namely bisphenol A (BPA), nonylphenol (NP) and octylphenol (OP), in urine from women of uterine leiomyoma group (n=49) and control group (n=29), by using solid-phase extraction (SPE) coupled with liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Urine samples were spiked with 2,4,6-tribromophenyl-terminated tetrabromobisphenol-A carbonate oligomer (TBBPA) and nonylphenol D8 (NP-D8) as internal standard (I.S...
November 1, 2013: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Moshe Matan, Elena Axelman, Benjamin Brenner, Yona Nadir
STUDY QUESTION: What is the effect of estrogen on heparanase procogulant activity? SUMMARY ANSWER: Estrogen increases heparanase procoagulant activity. WHAT IS KNOWN ALREADY: Estrogen therapy increases the risk of thrombosis and was previously found to up-regulate heparanase expression. Heparanase is involved in angiogenesis and metastasis, and has been shown to form a complex with tissue factor (TF) and also shown to enhance the generation of factor Xa...
September 2013: Human Reproduction
Ting-Ting Chen, Tai-Yuan Huang, Ryh-Nan Pan, Guo-Ping Chang-Chien, Mei-Chich Hsu
Raloxifene is one of the selective estrogen receptor modulators and is often used to prevent and treat osteoporosis in postmenopausal women. Because of the indirect impact on serum testosterone levels and the potential ability for performance enhancement, it is banned by the World Anti-Doping Agency (WADA). This study established a fast, sensitive and selective liquid chromatography-tandem mass spectrometry method to quantify total raloxifene (unchanged and glucuronidated) in human urine for doping analysis...
July 2013: Journal of Analytical Toxicology
Roberto Flores, Jianxin Shi, Barbara Fuhrman, Xia Xu, Timothy D Veenstra, Mitchell H Gail, Pawel Gajer, Jacques Ravel, James J Goedert
BACKGROUND: High systemic estrogen levels contribute to breast cancer risk for postmenopausal women, whereas low levels contribute to osteoporosis risk. Except for obesity, determinants of non-ovarian systemic estrogen levels are undefined. We sought to identify members and functions of the intestinal microbial community associated with estrogen levels via enterohepatic recirculation. METHODS: Fifty-one epidemiologists at the National Institutes of Health, including 25 men, 7 postmenopausal women, and 19 premenopausal women, provided urine and aliquots of feces, using methods proven to yield accurate and reproducible results...
2012: Journal of Translational Medicine
Muna S Nahar, Chunyang Liao, Kurunthachalam Kannan, Dana C Dolinoy
Widespread exposure to the endocrine active compound, bisphenol A (BPA), is well documented in humans. A growing body of literature suggests adverse health outcomes associated with varying ranges of exposure to BPA. In the current study, we measured the internal dose of free BPA and conjugated BPA and evaluated gene expression of biotransformation enzymes specific for BPA metabolism in 50 first- and second-trimester human fetal liver samples. Both free BPA and conjugated BPA concentrations varied widely, with free BPA exhibiting three times higher concentrations than conjugated BPA concentrations...
February 2013: Journal of Biochemical and Molecular Toxicology
Estatira Sepehr, Marketa Lebl-Rinnova, Meagan K Mann, Samantha L Pisani, Mona I Churchwell, Donna L Korol, John A Katzenellenbogen, Daniel R Doerge
Estrogen receptor (ER) subtype specific agonists, diarylpropionitrile (DPN) for ERβ and propylpyrazoletriol (PPT) for ERα, are pharmacological probes used frequently to define mechanisms for estrogen actions in vitro and in vivo. Quantitative analytical methodology was developed and validated for DPN and PPT, based on synthetic stable labeled analogs (DPN-d(4) and PPT-d(5)) using isotope dilution liquid chromatographic tandem electrospray mass spectrometric detection. The validated method produced high sensitivity, with detection limits of 0...
December 2012: Journal of Pharmaceutical and Biomedical Analysis
Harini Chowdary Vadlamudi, Y Prasanna Raju, B Rubia Yasmeen, Jayasri Vulava
The colon is composed of four distinct layers such as serosa, muscularis externa, sub mucosa and mucosa. There exists a difference in the anatomy, neural and blood supply and absorption characteristics as the length of the colon is traversed. At birth the mucosal surface of the colon is similar to that of the small intestine but rapid changes occur with the loss of the villi leaving flat mucosa with deep crypts. The existence of receptors like muscarinic M3, cholecystokinin1, Eph, Erb B, estrogen (α, β), gastrin releasing peptide, killer Ig like receptor, lymphocyte-endothelial receptor, notch, pregnane X, substance P and peroxisome proliferator-activated γ receptor can be utilized as a promising approach for targeting...
November 2012: Current Drug Delivery
David Hala, Lene H Petersen, Dalma Martinovic, Duane B Huggett
In this study, an in silico genome-scale metabolic model of steroidogenesis was used to investigate the effects of hypoxic stress on steroid hormone productions in fish. Adult female fathead minnows (Pimephales promelas) were exposed to hypoxia for 7 days with fish sub-sampled on days 1, 3 and 7 of exposure. At each time point, selected steroid enzyme gene expressions and steroid hormone productions were quantified in ovaries. Fold changes in steroid enzyme gene expressions were used to qualitatively scale transcript enzyme reaction constraints (akin to the range of an enzyme's catalytic activity) in the in silico model...
May 15, 2012: Journal of Experimental Biology
Andrea G Edlow, Mei Chen, Nicole A Smith, Chensheng Lu, Thomas F McElrath
Bisphenol A (BPA) is an estrogenic compound widely used in polycarbonate plastics. The placental enzyme β-glucuronidase may deconjugate BPA into its "free" active form. We sought to quantify levels of conjugated and free BPA in second and third trimester amniotic fluid. Liquid chromatography coupled with mass spectrometry was used to measure BPA concentrations in 20 second trimester and 20 third trimester amniotic fluid specimens. Total BPA was detected in 16/20 second trimester samples; levels ranged from non-detectable to 0...
August 2012: Reproductive Toxicology
Hideki Masaki, Takami Miki
Bone mass of elderly women reduces after menopause, but the rate of reduction differ individually especially in the elderly, because bone metabolism of the elderly is influenced by many factors such as hormones, fractures, drugs, ability of exercise and/or nutritional level. Therefore, it is quite difficult to determine the normal ranges of the metabolism. As a whole, aging accelerates bone turnover slowly with wide range of individual variation. Subnormal renal function may effect on the excretion or metabolism of bone markers, such as osteocalcin...
September 2011: Clinical Calcium
Mikhail F Borisenkov, Larissa A Bakutova, Dmitry S Latkin, Victoria V Golovchenko, Fedor V Vityazev
The purpose of this study was to investigate the in vitro effects of vegetable carbohydrates on the activity of microbial β-glucuronidase (βG) and the adsorption of the enzyme on carbohydrates. This study used pectin-protein complexes (PPCs) with molecular weights of 300 kDa isolated under conditions simulating a gastric environment from cabbage (HCl-PPCC and HCl+pepsin-PPCCP) and sweet pepper (PPCP and PPCPP). As a sample for comparison, microcrystalline cellulose was used. The activity of βG from Escherichia coli was determined spectrophotometrically by the formation of the colored product from the breakdown of phenolphthalein-β-D-glucuronide...
September 28, 2011: Journal of Agricultural and Food Chemistry
Jeroen C W Rijk, Helen Ashwin, Sandra J A van Kuijk, Maria J Groot, Henri H Heskamp, Toine F H Bovee, Michel W F Nielen
Receptor binding transcription activation bioassays are valuable tools for the screening of steroid hormones in animal feed and supplements. However, steroid derivatives often lack affinity for their cognate receptor and do not show any direct hormonal activity by themselves. These compounds are thus not detected by these kinds of bioassays and need a bioactivation step in order to become active, both in vivo and in vitro. In this study a comparison was made between different in vitro activation methods for hormone esters and hormone glycosides...
August 26, 2011: Analytica Chimica Acta
Ciğdem Berna Ege, Metin Akbulut, Osman Zekioğlu, Necmettin Ozdemir
INTRODUCTION: Inhibitors of tumor angiogenesis and metastasis are emerging as important new drug candidates for cancer therapy. Galectin-3 and heparanase have been shown to function in tumor progression and metastatic spread. Both of them exert pleiotropic effects; proliferation, cell migration, differentiation and tissue remodeling. The aim of this study was to investigate heparanase and galectin-3 expression in endometrioid and serous carcinomas of the endometrium and their relation with well-known prognostic factors, in addition to estrogen, progesterone, C-erbB-2, Ki-67 and p53...
November 2011: Archives of Gynecology and Obstetrics
Rentsenkhand Sambuu, Mitsuhiro Takagi, Satoshi Shiga, Seiichi Uno, Emiko Kokushi, Zhao Namula, Takeshige Otoi, Akio Miyamoto, Eisaburo Deguchi, Johanna Fink-Gremmels
Zearalenone (ZEN) and its metabolites are important nonsteroidal estrogenic mycotoxins that cause reproductive disorders in domestic animals, especially pigs. We aimed to simultaneously detect ZEN and its metabolites á-zearalenol (α-ZOL) and β-zearalenol (β-ZOL) in porcine follicular fluid (FF) by liquid chromatography-tandem mass spectrometry. ZEN and α-ZOL, but not β-ZOL, were detected in all pooled FF samples collected from coexisting follicles (diameter ≥ 6 mm) within 10 ovaries. Furthermore, ZEN and α-ZOL were detected in samples pretreated with β-glucuronidase/arylsulfatase, but not in those left untreated, suggesting that the FF samples contained glucuronide-conjugated forms of the mycotoxins that may be less harmful to porcine oocytes due to glucuronidation affecting the receptor binding...
April 2011: Journal of Reproduction and Development
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"