Dienestrol

Dienestrol is a synthetic non-steroidal estrogen receptor (ER) agonist and an active metabolite of diethylstilbestrol (Item No. 10006876).^1,2,3 Dienestrol binds to ERα and ERβ (K_is = 0.05 and 0.03 nM, respectively) and activates ERα in a reporter assay (EC₅₀ = 3.23 nM).^1,2 It also inhibits porcine microtubule assembly and induces disassembly of preformed microtubules when used at concentrations of 50 and 100 μM, respectively, in cell-free assays.⁴ Oral administration of dienestrol (1.5-6.25 µg/kg) to pregnant rats during gestation and lactation decreases sperm motility and viability and induces prostatitis in mature male offspring.⁵ It induces abortions when administered to pregnant rats at 50 and 75 µg/kg. Formulations containing dienestrol have been used in the treatment of atrophic vaginitis and vulvar atrophy.

WARNING This product is not for human or veterinary use.

1. Kuiper, G.G.J.M., Carlsson, B., Grandien, K., et al. Comparison of the ligand binding specificity and transcript tissue distribution of estrogen receptors α and β. Endocrinology 138(3), 863-870 (1997).

2. Stypuła-Trębas, S., Minta, M., Radko, L., et al. Application of the yeast-based reporter gene bioassay for the assessment of estrogenic activity in cow’s milk from Poland. Environ. Toxicol. Pharmacol. 40(3), 876-885 (2015).

3. Neumann, H.-G., Metzler, M., and Töpner, W. Metabolic activation of diethylstilbestrol and aminostilbene-derivatives. Arch. Toxicol. 39(1-2), 21-30 (1977).

4. Sato, Y., Murai, T., Oda, T., et al. Inhibition of microtubule polymerization by synthetic estrogens: Formation of a ribbon structure. J. Biochem. 101(5), 1247-1252 (1987).

5. Schreiber, E., Alfageme, O., Garcia, T., et al. Oral exposure of rats to dienestrol during gestation and lactation: Effects on the reproductive system of male offspring. Food Chem. Toxicol. 128, 193-201 (2019).