Genistein (C15H10O5) is a naturally occurring compound that structurally belongs to a class of compounds known as isoflavones. It is described as an angiogenesis inhibitor and a phytoestrogen. It was first isolated in 1899 from the dyer's broom, Genista tinctoria; hence, the chemical name. The compound structure was established in 1926, when it was found to be identical with that of prunetol. It was chemically synthesized in 1928. It has been shown to be the primary secondary metabolite of the Trifolium species and Glycine max L. Natural occurrences Isoflavones such as genistein and daidzein are found in a number of plants including lupin, fava beans, soybeans, kudzu, and psoralea being the primary food source, also in the medicinal plants, Flemingia vestita and F. macrophylla, and coffee. It can also be found in Maackia amurensis cell cultures. Biological effects Besides functioning as an antioxidant and anthelmintic, many isoflavones have been shown to interact with animal and human estrogen receptors, causing effects in the body similar to those caused by the hormone estrogen. Isoflavones also produce non-hormonal effects. Molecular function Genistein influences multiple biochemical functions in living cells: full agonist of ERβ (EC50 = 7.62 nM) and, to a much lesser extent (~20-fold), full agonist or partial agonist of ERα agonist of G protein-coupled estrogen receptor (affinity of 133 nM) activation of peroxisome proliferator-activated receptors (PPARs) inhibition of several tyrosine kinases inhibition of topoisomerase inhibition of AAAD direct antioxidation with some pro oxidative features activation of Nrf2 antioxidative response stimulation of autophagy inhibition of the mammalian hexose transporter GLUT1 contraction of several types of smooth muscles modulation of CFTR channel, potentiating its opening at low concentration and inhibiting it a higher doses. inhibition of cytosine methylation inhibition of DNA methyltransferase inhibition of the glycine receptor inhibition of the nicotinic acetylcholine receptor Activation of PPARs Isoflavones genistein and daidzein bind to and transactivate all three PPAR isoforms, α, δ, and γ. For example, membrane-bound PPARγ-binding assay showed that genistein can directly interact with the PPARγ ligand binding domain and has a measurable Ki of 5.7 mM. Gene reporter assays showed that genistein at concentrations between 1 and 100 uM activated PPARs in a dose dependent way in KS483 mesenchymal progenitor cells, breast cancer MCF-7 cells, T47D cells and MDA-MD-231 cells, murine macrophage-like RAW 264.7 cells, endothelial cells and in Hela cells. Several studies have shown that both ERs and PPARs influenced each other