7&agr;-Methyl-ethinyl estradiol is not a metabolite of tibolone but a chemical stress artifact
@article{Drge20077agrMethylethinylEI, title={7\&agr;-Methyl-ethinyl estradiol is not a metabolite of tibolone but a chemical stress artifact}, author={Melloney Joyce Dr{\"o}ge and Freddy Oostebring and Ep Oosting and Herman A. M. Verheul and Helenius Jan Kloosterboer}, journal={Menopause}, year={2007}, volume={14}, pages={474-480} }
Objective:This study was conducted to establish whether 7&agr;-methyl-ethinyl estradiol (7&agr;-MEE) in plasma from postmenopausal women treated with tibolone is a metabolite or an artifact. Design:Clinical samples with known levels of tibolone metabolites, plus plasma samples spiked with tibolone and metabolites, were analyzed for levels of 7&agr;-MEE using liquid chromatography-mass spectometry (LC-MS/MS) with and without derivatization. Results:Approximately 20 to 40 pg/mL 7&agr;-MEE was…
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Tibolone is not aromatized in postmenopausal women
- MedicineClimacteric : the journal of the International Menopause Society
- 2008
The conclusions of the study were that the THEBES results confirm previous findings that tibolone does not induce endometrial hyperplasia or carcinoma in postmenopausal women, and it is associated with a better vaginal bleeding profile than conjugated equine estrogens/medroxyprogesterone acetate.
[Effect of tibolone on endometrium of castrated rats].
- Biology, MedicineRevista brasileira de ginecologia e obstetricia : revista da Federacao Brasileira das Sociedades de Ginecologia e Obstetricia
- 2009
High doses of tibolone, given for long periods of time to castrated female rats, have an estrogenic effect which can be dose-dependent, causing proliferation in the endometrium and causing changes in the cell differentiation (squamous metaplasia), but do not lead to hyperplasia.
Recent advances on the action of estrogens and progestogens in normal and pathological human endometrium
- Biology, MedicineHormone molecular biology and clinical investigation
- 2010
Treatment with hormone replacement therapy (estrogens+progestogens), as well as with tibolone, is most effective in protecting this tissue by climacteric alterations, owing to the significant decrease of ovarian hormones.
The other side of progestins: effects in the brain.
- BiologyJournal of molecular endocrinology
- 2016
The role exerted by different progestins, currently used for contraception or in postmenopausal hormone replacement therapies, in regulating cognitive functions as well as social behavior and mood is reported.
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