Possible Interaction: Estrone and Progestins

“Obesity may worsen prognosis as a result of increased synthesis of estrogens in peripheral fat and one possible approach to this problem is to use progestins to counteract the estrogenic drive.”

“These progestins , as well as tibolone, can also block the conversion of estrone to estradiol by the inhibition of the 17beta-hydroxysteroid dehydrogenase type I (17beta-HSD-1).”

“Various progestins (e.g. promegestone, nomegestrol acetate, medrogestone, 17-deacetyl norgestimate, dydrogesterone and its 20-dihydro derivative), as well as tibolone and its metabolites, have been shown to inhibit estrone sulfatase and 17beta-hydroxysteroid dehydrogenase.”

“In another series of studies, it was also demonstrated that various progestins are very active in inhibiting the 17 beta-hydroxysteroid dehydrogenase for the conversion of estrone to estradiol.”

“Our results suggest that synthetic progestogens can influence the estrone sulfatase activity measured in human breast carcinoma tissues.”

“This finding suggests that it is not the individual component alone, but the combined action of estrogenic and progestational components which determines the potency of an oral contraceptive agent.”

“The theory that the side effects of continuous estrogenic exposure can be averted by periodic interruption with progestins is also discussed.”

“The progestagen sponge plus 3 beta-HSD inhibitor treatment also caused a significant increase in oestrous cycle duration of approximately 1.5 days.”

“The assay of the monoamine oxidase enzyme did not reveal any significant change, though the estrogenic and progestogenic hormones were found to have opposing effects on the enzyme levels.”

“In general progestational effects are antagonized by estrogens and estrogenic effects are inhibited by progestins although certain potentiations are seen.”