2-hydroxyestradiol

2-Hydroxyestradiol is an endogenous steroid and catechol estrogen metabolite of estradiol. It is formed by hydroxylation of estradiol at the 2nd carbon of the A-ring, primarily catalyzed by cytochrome P450 enzymes such as CYP1A1/1A2 and CYP3A4 in tissues including liver, uterus, breast, and brain[4][7]. Structurally similar to its parent hormone but with an additional hydroxyl group that reduces its affinity for estrogen receptors compared to estradiol[4][5]. \n**Mechanism of Action:** \nIt has minimal estrogenic activity due to low affinity for estrogen receptors but retains biological activities such as antioxidant effects and modulation of lipid metabolism. It can also interact with catecholamine systems by competing with catecholamines for binding to enzymes like catechol O-methyltransferase (COMT) and tyrosine hydroxylase[7]. In vitro studies show it can induce oxidative DNA damage and apoptosis in human mammary epithelial cells[6]. In vivo studies suggest potential benefits on cardiovascular health (e.g., improved endothelial function), bone health (inhibits bone resorption), metabolic regulation (attenuates obesity development), nephropathy reduction, blood pressure lowering, cholesterol reduction[4][6].

Other names

(17β)-estra-1,3,5(10)-triene-2,3,17-triol2-hydroxy-17beta-estradiol2-hydroxy-17β-estradiol2-Hydroxyestradiol-17beta2-OH-Estradiol