%0 Journal Article
%A Ridichie, Amalia Ridichie
%A Ledeti, Adriana Ledeti
%A Bertici, Răzvan Bertici
%A Ledeți, Ionuț Ledeți
%D 2025
%J Journal of Experimental Pharmacology and Toxicology

%@ 3091-0595

%V 2
%N 2
%P 4

%T Understanding the Biological Activity of Endogenous Estrogens: Current Knowledge and Insights
%M doi:10.6425/022025jept004
%U https://j-pharmacol-tox-exp.com/article/2/2/19
%X Estrogens represent a class of cholesterol-derived female sex hormones, essential in the regulation of numerous physiological processes. On the basis of their origin, they can be classified into endogenous (synthesized within the body) or exogenous (introduced from external sources) compounds. In humans, four types of endogenous estrogens have been identified, namely estrone, 17-β-estradiol, estriol, and estetrol. Despite their similarities in chemical structures, they have distinct receptor affinities and functional roles at different life stages. This review presents, in addition to an overview of their diverse physiological functions, a discussion of the three estrogen receptors (ERα, ERβ, and GPER1) currently investigated as possible targets in the development of new therapeutic strategies for hormone-dependent breast cancer.