Comparative binding studies of curcumin and tangeretin on up-stream elements of NF-kB cascade: a combined molecular docking approach

Abstract

The hyper-activation of NF-kB (nuclear factor kappa-light-chain-enhancer of activated B cells) in cellular system is associated with inflammation, cancer and other human diseases. The core elements of NF-kB cascade might regulate the translocation and activation of NF-kB transcription factor. In the present study, we focused on active site analysis and molecular docking studies of core elements of NF-kB pathway. Curcumin and tangeretin are the natural compounds used as ligands in this docking study. We performed comparative docking studies by applying individual and combination of ligands on drug target proteins (NF-kB core elements). The docking energy and active site residues interacts with curcumin and tangeretin were obtained as follows: IKK complex (− 4.13 kcal/mol; Leu737, Asp738, Trp739, Lys96 and − 2.76 kcal/mol; Thr735, Ser733), proteosome (− 4.38 kcal/mol; Gln49, Asp52, Arg42, Glu24 and − 4.05 kcal/mol; Asp52), RelA (− 6.00 kcal/mol; Arg304, Thr308, Arg302 and − 3.46 kcal/mol; Arg302, Thr305) and NF-kB (− 5.42 kcal/mol; Cys359, Lys445, Lys541, Glu360 and − 5.31 kcal/mol; Lys444, Tyr357), respectively. Hex combined docking score obtained for IKK complex; proteosome, RelA and NF-kB are − 88.28, − 98.64, − 53.89 and − 80.55 kcal/mol, respectively. In this study, we found that proteosome has shown the highest docking energy (− 98.64 kcal/mol) and it is suggested to be as crucial drug target in NF-kB cascade. However, further experimental and clinical verification is needed for clear evidence.