Diosgenin inhibits tumor necrosis factor-induced tissue factor activity and expression in THP-1 cells via down-regulation of the NF-κB,Akt,and MAPK signaling pathways

AIM:To investigate whether diosgenin could modulate tissue factor(TF) procoagulation activity,expression,and related signal transduction pathways.METHODS:Human THP-1 monocytic cells were exposed to tumor necrosis factor-(TNF-,10 ngmL-1) with or without diosgenin(0.01,0.1,and 1 molL-1) for 2 h or 5 h to induce TF procoagulant activity and expression,which were determined by the simplified chromogenic assay,reverse transcription-polymerase chain reaction(RT-PCR),real-time quantitative PCR,and Western blotting assays.In addition,the activation of the NF-B,Akt,and MAPK signaling pathways were also measured by Western blotting.RESULTS:Diosgenin significantly inhibited TNF--induced TF procoagulant activity at concentrations of 0.01 to 1 molL-1 with IC50 of 0.25 molL-1.It also reduced protein expression and mRNA accumulation of TF dose-dependently in activated THP-1 cells.TNF- stimulated significantly phosphorylation on Ser536 of NF-B/p65,Ser473 of Akt at 5-15 min,and activations of IKK- and ERK at 15-30 min.Diosgenin(1 molL-1) could inhibit the phosphorylation of NF-B/p65,IKK-,Akt,ERK,and JNK,but had no remarkable effects on IB and p38 phosphorylation in THP-1 cells.CONCLUSION:Diosgenin inhibits TNF--induced TF activity and expression in monocytes,partly due to its down-regulation of the phosphorylation of NF-B/p65,IKK-,Akt,ERK,and JNK.