MOLECULAR DOCKING STUDIES ON FLAVONOID COMPOUNDS: AN INSIGHT INTO AROMATASE INHIBITORS
Objective: Aromatase is a key enzyme that plays a crucial role in the synthesis of estrogen and has a major effect in pathogenesis of estrogenâ€‘dependent disease, including breast cancer, endometrial cancer, and endometriosis. The abnormal over expression of aromatase can be inhibited by aromatase inhibitors. The objective of the present study is to evaluate the binding interaction of flavonoid compounds with cytochrome P450 enzyme aromatase, which is involved in the metabolism of estrogens and considered as a powerful target for treatment of estrogen-dependent breast cancers.
Methods: To understand the mechanisms involved in the binding of flavonoid compounds and their interactions with the binding site of aromatase, molecular docking studies were carried using Autodock 4.2.
Results: The docking results revealed that, benzoflavanones showed higher binding affinity compared to other class of compounds. The presence of hydrogen bond interaction and cationâ€“Ï€ interaction contributed to their higher binding affinity. The flavonoid compounds with unsubstituted or less substituted rings showed higher binding affinity than those with substituted rings. The hydrogen bonding interactions were predominant in all the classes of compounds considered for the study and were found to be important for inhibition. The docking studies showed that the binding energies mainly depend on aromatic properties like cationâ€“Ï€ and Ï€â€“Ï€ interactions. These properties play a key role in determining the biological activity of flavonoid compounds.
Conclusion: The present findings provided valuable information on the binding process of flavonoid compounds to the binding site of aromatase and revealed the structural requirement needed for binding.
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