Possible Interaction: Progestins and Medroxyprogesterone Acetate

“Conclusions: Triglyceride levels during EPT every day with conventional doses of CEE and MPA increased more in overweight and obese postmenopausal women in association with increased estrogen levels.”

“Effect-time studies indicate that injection of MPA and L. chuanxiong extract raised area-under-curve of progestogenic activity in sera by 8.2-fold (p<0.001) and 4.5-fold (p<0.01) respectively, compared to sera from rats administered vehicle only.”

“LH levels were suppressed after a 6-day progestin treatment in the medroxyprogesterone acetate + hMG and dydrogesterone +hMG groups, but there was a rebound of LH values in the progesterone +hMG group.”

“CONCLUSIONS:The inhibitory effect of MPA on both basal and TNF&agr;-induced MMP-9 activity and gene expression in primary amnion cells demonstrate a possible mechanism by which progestins may prevent fetal membrane weakening leading to preterm premature rupture of membranes.”

“There is strong evidence that VTE risk is greater in women using medroxyprogesterone acetate compared with those receiving other progestins.”

“With respect to the different pharmacological classes of progestogens , there is evidence for a deleterious effect of medroxyprogesterone acetate on VTE risk.”

“However, MPA antagonized the E2-induced significant reduction of MCP-1 synthesis, with the difference between both progestins being significant (p < 0.01).”

“A significant decrease in TGF-alpha mRNA was apparent 6 h after exposure to MPA and a further decrease was seen 12-24 h after addition of the progestin.”

“The maximum was found at doses between 0.1-1 microM. The activities reduced steadily from the maximum stimulation to … 50% when the concentration of MPA increased from 1-30 microM. In addition, initial treatment of stroma cells with MPA (1-3 days) resulted … increase of activity after progestin ….”

“Moreover, the E2DH activity was 2 to 5 times higher in epithelial cells cultured in the presence of the progestin medroxyprogesterone acetate , whereas it remained unchanged in fibroblasts cultured under the same conditions.”