Figure 4

Suppressive effects of ginsenosides on U937 cells stimulated with TNF-α. (A) Nine ginsenosides were standardized to concentrations in the PGSE at 3 mg/ml according to Table 1. U937 cells were treated with ginsenosides for 24 hours following with 20 units/ml TNF-α stimulation for 2 hours, and the transcription of CXCL-10 was measured by quantitative RT-PCR as described in Methods. (B) Ginsenosides including Rb₁, Rb₂, Rc, Rd, Re, Rf, Rg₁, Rg₃ and Rh₁ were pooled together to investigate the combinatorial effect of the nine ginsenosides on CXCL-10 transcription following TNF-α stimulation by using quantitative RT-PCR. (C) Comparable inhibitory effects of the ginseng extract (PGSE) and the mixture of individual ginsenosides on CXCL-10 transcription. U937 cells were treated with 3 mg/ml of PGSE or the mixture of GS (that is equivalent to 3 mg/ml of PGSE) for 24 hours following with 20 units/ml of TNF-α stimulation for another 2 hours. The transcription of CXCL-10 was measured by quantitative RT-PCR as described in Methods. Values represent the average ± SD of three independent experiments and statistically analyzed by two tailed, paired t-test. ψ: p < 0.005; †: p < 0.01; *: p < 0.05. GS, ginsenosides; PGSE, 70% ethanol-water extracts of ginseng.