Curcumin and capsaicin modulates LPS induced expression of COX-2, IL-6 and TGF-β in human peripheral blood mononuclear cells.

The mechanism of action of treatment of either curcumin or capsaicin or in combination on LPS (Lipopolysaccharide) induced inflammatory gene expression in peripheral blood mononuclear cells (PBMCs) was investigated using RT-PCR and in silico docking methods. RT-PCR analysis has shown that the curcumin and capsaicin significantly reduced LPS induced over expression of COX-2, IL-6 and TGF-β in PBMCs. Whereas combined molecules demonstrated synergistic response on the reduction of COX-2, IL-6 and TGF-β over expression in LPS induced PBMCs as compared to individual molecules. Further, The docking of curcumin and capsaicin at the active pockets of COX-2, IL-6 and TGF-β has shown - 3.90, - 4.49 and - 5.61 kcal/mol binding energy for curcumin and - 3.80, - 4.78 and - 5.76 kcal/mol binding energy for capsaicin, while multiple ligand simultaneous docking (MLSD) of both molecules has shown higher binding energy of - 4.24, - 5.35 and - 5.83 kcal/mol respectively. This has demonstrated the efficacy of combined curcumin and capsaicin against the LPS induced expression of pro-inflammatory cytokines in PBMCs. These results attributed the coordinated positive modulation on biochemical and molecular cellular process by combined curcumin and capsaicin as compared to individual molecules.