Possible Interaction: Progestins and Progesterone

“Since the intracellular effects on gene expression and cell signaling of steroids are mediated via intracellular steroid receptors, differential actions via the progesterone and other steroid receptors and their isoforms, are likely to be the major cause of differential intracellular actions of progestins.”

“Pretreatment of cells with progesterone receptor-encoding adenovirus and progestin inhibited the development of s.c.”

“The dual effect of progesterone and progestins on the cell cycle has been demonstrated, suggesting that according to the duration of administration, the same steroid can induce cells to enter the multiplication phase or to enter a resting state.”

“The largest study administering oral progestin using 300 mg micronized progesterone reported a 58.9% improvement in VMS (vs 23.5% in placebo group, n = 133), whereas the largest study using transdermal progesterone reported no improvement (n = 230).”

“In luteal support, a Cochrane review reported that progestogens were associated with a higher rate of live births or ongoing pregnancy in the progesterone group (odds ratio 1.77, 95% confidence interval (CI) 1.09–2.86).”

“The progesterone resistance is counteracted by progestins (Medroxyprogesterone acetate, Dienogest, Danazol, Levonorgestrel) or by Selective progesterone receptor modulators, a class of drugs under development.”

“In the case of the other five reductases, gestagens had remarkably stronger inhibitory effects at a concentration of 25 μM ( progesterone : 66-88% inhibition; drospirenone: 26-87% inhibition) in comparison to estrogens (estradiol: 17-51% inhibition; ethinylestradiol: 14-79% inhibition) and androgens (14-78% inhibition).”

“In theory, potent progestins could reactivate progesterone signaling that leads to follicle rupture, thereby impacting the effectiveness of UPA as EC.”

“AOH exhibited a weak oestrogenic response when tested in the oestrogen responsive RGA and binding of progesterone to the progestagen receptor was shown to be synergistically increased in the presence of AOH.”

“Binding of progesterone to the progestagen receptor was shown to be synergistically increased in the presence of ZEN, α-ZOL or β-ZOL.”