Molecular Mechanism Underlying Hesperetin-induced Apoptosis by in silico Analysis and in Prostate Cancer PC-3 Cells

Aim: To investigate the molecular mechanisms underlying triggering of apoptosis by hesperetin using in silico and in vitro methods. Methods: The mechanism of binding of hesperetin with NF-kappa B and other apoptotic proteins like BAX, BAD, BCL2 and BCLXL was analysed in silico using Schrodinger suite 2009. In vitro studies were also carried out to evaluate the potency of hesperetin in inducing apoptosis using the human prostate cancer PC-3 cell line. Results: Hesperetin was found to exhibit high-affinity binding resulting from greater intermolecular forces between the ligand and its receptor NF-kappa B (-7.48 Glide score). In vitro analysis using MTT assay confirmed that hesperetin reduced cell proliferation (IC50 values of 90 and 40 mu M at 24 and 48h respectively) in PC-3 cells. Hesperetin also downregulated expression of the anti-apoptotic gene BCLXL at both mRNA and protein levels and increased the expression of pro-apoptotic genes like BAD at mRNA level and BAX at mRNA as well as protein levels. Conclusion: The results suggest that hesperetin can induce apoptosis by inhibiting NF-kappa B.