In silico exploration of the mechanistic insights: interactions of curcumin, quercetin, and ethephon with estrogen receptors and steroidogenic enzymes

Background: Ethephon is a widely used plant growth regulator in agriculture to promote fruit ripening, abscission, flower induction and seed germination which hold chances of mammalian toxicity due to environmental and food contamination. Curcumin, a polyphenolic compound obtained from turmeric and quercetin, a flavonoid present in several vegetables and fruits can influence pituitary and ovarian hormones and mediate benefits on reproductive processes. In this context, the present study was undertaken with the objectives of determining whether curcumin and quercetin have an ameliorative effect on probable adverse effects of ethephon in reproductive system by in silico analysis. Method: To identify mechanism of ethephon, quercetin and curcumin, molecular docking has been performed. Three dimensional structures of ER α (PDB Id: 1A52), ER β (PDB Id: 1X7B), CYP19A1 (PDB Id: 3S79), CYP11A1 (PDB Id: 3NA1), CYP17 (PDB Id: 3RUK), 17βHSD (PDB Id: 1BHS), StAR proteins (PDB Id:3P0L) were retrieved from RCSB and docking was done with AutoDock V 4.0 using three ligands. Results: The binding energies of curcumin and quercetin showed more binding energy ranging from -7.97 to -3.12 where as that of ethephon was from -4.44 to -1.56 with all the proteins under study. Curcumin and quercetin showed no affinity towards ER α. Ethephon showed more affinity to ER α than curcumin and quercetin (217.20 and 32.87 kcal/mol respectively). Conclusion: From this study, it could be concluded that curcumin and quercetin can provide an ameliorative effect on reproductive toxicity that can be caused by ethephon.