Lack of aromatisation of the 3-keto-4-ene metabolite of tibolone to an estrogenic derivative

@article{Raobaikady2006LackOA,
  title={Lack of aromatisation of the 3-keto-4-ene metabolite of tibolone to an estrogenic derivative},
  author={B. Raobaikady and M. F. Parsons and M. Reed and A. Purohit},
  journal={Steroids},
  year={2006},
  volume={71},
  pages={639-646}
}
Tibolone is used for the treatment of climacteric symptoms in postmenopausal women. It is metabolised in a tissue-specific manner so that while some metabolites exert estrogenic effects on bone and the CNS, others are thought to protect the breast and endometrium from estrogenic stimulation. Tibolone is a 7alpha-methyl derivative of 19-norethynodrel. Since the introduction of synthetic progestagens for therapeutic use there has been considerable controversy as to whether they can undergo… Expand
Can 19-nortestosterone derivatives be aromatized in the liver of adult humans? Are there clinical implications?
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  • Medicine
  • Climacteric : the journal of the International Menopause Society
  • 2007
TLDR
19-nortestosterone derivatives (norethisterone, norethynodrel, tibolone) can readily be aromatized in the adult human liver, which leads to the formation of the potent estrogens ethinylestradiol from norehisterone or nore fourthodrel and 7α-methyl-ethinylest radiol from tibiaolone. Expand
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7&agr;-Methyl-ethinyl estradiol is not a metabolite of tibolone but a chemical stress artifact
TLDR
7&agr;-MEE is not a metabolite of tibolone but is a chemical artifact generated during analytical procedures with derivatization, and cannot be demonstrated in plasma from postmenopausal women after single or multiple doses of tIBolone. Expand
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The list of prohibited substances of the World Anti-Doping Agency (WADA) classifies the administration of several steroids in sports as doping. Their analysis is generally performed using urineExpand
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Estrogenic effects of 7α-methyl-17α-ethynylestradiol: a newly discovered tibolone metabolite
Abstract Tibolone is a synthetic steroid that is prescribed to postmenopausal women for relief of climacteric symptoms and prevention of osteoporosis. It has been reported to be metabolized in aExpand
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