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Transdermal estrogen therapy and the risk of breast cancer: a clinical appraisal
Published in A. R. Genazzani, Hormone Replacement Therapy and Cancer, 2020
Estrone sulfate is formed by peripheral conversion from estradiol and estrone. Studies have documented that 65% of the estradiol and 54% of the estrone produced are converted to estrone sulfate15. In absolute terms, the circulating level of estrone sulfate is 10–25 times that of estrone and estradiol. Estrone sulfate thus functions as a major reservoir for estrone and estradiol16. Sulfatases in various tissues (and especially the breast) reduce the inactive estrone sulfate to estrone. Estrone is subsequently hydroxylated to estradiol by 17ß-OHSD. Sulfatase (and 17ß-OHSD) activity in breast tissue is quantitatively greater than that of aromatase, and is especially high in women with breast cancer12.
Estrogen treatment for senile dementia-Alzheimer’s type
Published in Barry G. Wren, Progress in the Management of the Menopause, 2020
H. Honjo, M. Urabe, K. Iwasa, T. Okubo, H. Tsuchiya, N. Kikuchi, T. Yamamoto, S. Fushiki, T. Mizuno, K. Nakajima, M. Hayashi, K. Hayashi
The main form of estrogen in women before menopause is E2, but after menopause the main form of estrogen is estrone sulfate (E1-S) which comes from dehydro-epiandrosterone (DHEA) and/or its sulfate after aromatization mainly in peripheral fat tissues. The level of serum estrone sulfate in postmenopausal women without any hormonal treatment was measured by direct radioimmunoassay2, 3. The serum level of EI-S in 18 women with AD was significantly lower than that in age-matched women without AD.
Alternate Pathways of Steroid Biosynthesis and the Origin, Metabolism, and Biological Effects of Ring B Unsaturated Estrogens
Published in Ronald Hobkirk, Steroid Biochemistry, 1979
B. R. Bhavnani, C. A. Woolever
There are a number of similarities between the metabolism of estrone and equilin in the human. Reduction to the β configuration at carbon-17 imparts an increased estrogenic potency to both compounds (Table 17). Estrone sulfate is the major form of the hormone in the serum.193 Free estrone and free equilin have relatively short half-lives (Figure 23). Estrone and its metabolites are excreted in the urine primarily as glucuronides and large amounts of very polar compounds are found.194,195
Transdermal delivery of bioidentical estrogen in menopausal hormone therapy: a clinical review
Published in Expert Opinion on Drug Delivery, 2020
Although the skin provides a significant barrier to absorption, certain medications are well absorbed and the benefits from the transdermal administration of medication vs oral and injectable are myriad (Table 1) [20]. For example, transdermal administration is convenient, painless and offers improvement in the maintenance of plasma drug concentrations. Another advantage is the avoidance of hepatic first pass metabolism seen with oral preparations [16] In fact, interest in the transdermal delivery of estrogen arose from the observation that oral estrogen induces a number of systemic metabolic effects through the first pass effect in the liver [21]. Transdermal administration of estrogen allows for lower doses because it avoids first pass metabolism and the need for GI absorption of an oral preparation. Multiple observational studies suggest that transdermal delivery of estrogen has a lower risk of stroke and venous thromboembolic disease than oral estrogen [22–27]. Additionally, the transdermal route yields an estradiol:estrone ratio that is more similar to that found in premenopausal women, which may be preferred given its more physiologic composition [28]. Estrogen delivered transdermally does not lead to the elevated levels of estrone sulfate seen with long term oral estradiol administration [29].
Determination of estrone sulfate, testosterone, androstenedione, DHEAS, cortisol, cortisone, and 17α-hydroxyprogesterone by LC-MS/MS in children and adolescents
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2020
Carina Ankarberg-Lindgren, Mats X. Andersson, Jovanna Dahlgren
The sulfo-conjugated estrone sulfate (E1S) is the most abundant estrogen precursor in the human circulation. As an estrogen, it has a relatively low biological activity; however, it is readily converted into other more powerful estrogen. In adults, serum E1S concentrations are 10-20 times higher than E1 and E2 levels, and E1S has a long half-life [3,22–25]. In humans, there is a suggestion that the conversion of E1S to E2 may have a biological role in the development of disease, i.e. the activity of tissue sulfatase enzyme may be elevated. However, to the best of our knowledge there are no published studies examining how serum concentration of E1S changes throughout puberty in children.
Current and emerging treatment options for endometriosis
Published in Expert Opinion on Pharmacotherapy, 2018
Simone Ferrero, Giulio Evangelisti, Fabio Barra
In the estrogen production pathway, steroid sulfatase enzyme is responsible for the conversion of E2 sulfate, estrone sulfate and dehydroepiandrosterone sulfate to their unconjugated forms. These hormones, having a long half-life and being found in high concentrations in blood and tissues, may act as a reservoir for the production of hormonally active estrogen. The mRNA expression of steroid sulfatase is five-fold higher in patients with ovarian endometriomas compared with the endometrium of patients not affected by endometriosis. Thus, this enzyme may contribute to the development of endometriosis, although its precise role when it is overexpressed is not completely elucidated.