Possible Interaction: Insulin and Progestins

“ObjectiveThe androgenic effect of progestogen , necessary in early postmenopausal hormone replacement therapy (HRT), may adversely affect insulin sensitivity as well as body fat distribution and thereby increase the cardiovascular risk profile.”

“An attenuation in insulin sensitivity was seen with added progestin.”

“ Progestin , however, appeared to attenuate the beneficial effects of transdermal estrogen and may alter the clearance of insulin.”

“A moderate dose of estrogen appears to increase insulin sensitivity but higher doses may attenuate this benefit and progestins may cause a decrease in insulin sensitivity.”

“The present results suggest a physiological role for progestins in increasing the responsiveness to insulin , which could, in turn, reverse the antiproliferative effect of progestins on estrogen action and thus decrease the efficacy of progestins in the treatment of breast cancer.”

“Progestins, on the other hand, exert a specific antiproliferative effect in the presence of estrogens, the effect of progestins being antagonized by the stimulatory action of insulin on cell growth.”

“The stronger the androgenic effect of progestins the more likely they are to disturb glucose tolerance and cause hyperinsulinism and insulin resistence.”

“When T-47D cells grown in insulin-containing medium were treated for 4 to 5 days with the synthetic progestin , ORG 2058, at a concentration of 10 nM, cell numbers were reduced to 10 to 20% of control.”

“At the same time, progestins increase the levels of the receptors for insulin , a common cell mitogen.”

“It is concluded that in vivo treatment of superovulated rats with insulin increases luteal progestagen production by increasing the content of cytochrome P450scc.”