Interaction of Coumarin Phytoestrogens with ER(α) and ER(β): A Molecular Dynamics Simulation Study

Coumarin phytoestrogens, as one of the important classes of phytoestrogens, have been proved to play an important role in various fields of human life. In this study, molecular simulation method including molecular docking and molecular dynamics methods were performed to explore the various effects between four classical coumarin phytoestrogens (coumestrol, 4-methoxycoumestrol, psoralen and isopsoralen), and estrogen receptors (ER(α,) ER(β)), respectively. The calculated results not only proved that the four coumarin phytoestrogens have weaker affinity than 17β-estradiol to both ER(α,) and ER(β), but also pointed out that the selective affinity for ER(β) is greater than ER(α). In addition, the binding mode indicated that the formation of hydrogen bond and hydrophobic interaction have an important effect on the stability of the complexes. Further, the calculation and decomposition of binding free energy explored the main contribution interactions to the total free energy.