The Synergistic Effect of Zinc, Coumestrol, Genestein and Daidzein on Proinflammatory Cytokines Production and Receptor Activator of NFκB Ligand Expression that Implicates in Bone Resorption

Several observations have showed the synergistic effect of nutrients elements andphytoestrogens on bone resorption elimination. Zn is one of the trace elements found toincrease the stimulatory effect of phytoestrogens including genestein, coumestrol and daidzeinon bone formation; however the synergistic modulation of Zn, genestein, coumestrol anddaidzein on proinflammatory-producing T-cells and receptor activator of NFκB ligand(RANKL) expression that implicated in osteoclast formation is still open area to debate. Thisstudy found that Zn enhanced the inhibitory effect of genistein, daidzein and coumestrol onTNF-α expression; however the same effect was shown with daidzein on IL-1β expressionwhile there is no further effect found with other compounds. Zn is only in combination withgenistein decreaseIL-6 expression; moreover Zn had additional effect on the inhibitory effectof all test phytoestrogens on RANKL expression in dose-dependent manner. In conclusion,Zn alone or in combination with phytoestrogens has an inhibitory effect on the expression ofpro-inflammatory cytokines and RANKL that play an important role in the promotion of boneresorption.