An antioxidant resveratrol significantly enhanced replication of hepatitis C virus

Figure 1 Organization of hepatitis C virus (HCV) RNA used in the replicon systems. A: Genome-length HCV RNA generated in OR6 cells; B: Subgenomic HCV RNA used in sKAH-5R and s1B-4R cells. Structural region of HCV RNA was deficient in the replicated RNA of sKAH-5R and s1B-4R cells.

Figure 2 Luciferase activity and cell viability of OR6 cells after addition of resveratrol (RVT) and astaxanthin (AXN) for 72 h. The indicated concentrations of RVT or AXN were added to the culture medium of OR6 cells, and after 72 h of culture, cells were harvested with Runilla lysis buffer and the lysate was subjected to the luciferase assay. Cell viability was evaluated by a trypan blue dye exclusion assay. A: Luciferase activity after addition of RVT; B: Cell viability after addition of RVT; C: Luciferase activity after addition of AXN; D: Cell viability after addition of AXN. ^aP < 0.05, ^bP < 0.01.

Figure 3 The effect of vitamin E (VE) on luciferase activity and cell viability of OR6 cells (72 h). Cells were treated with the indicated concentrations of VE for 72 h. A: Luciferase activity after addition of VE; B: Cell viability after addition of RVT and VE. ^bP < 0.01.

Figure 4 The effect of resveratrol on subgenomic replicon cells, sKAH-5R. RVT was added to the cells for 72 h and luciferase activity was assayed as was indicated in Figure 2. A: Luciferase activity after addition of RVT; B: Cell viability after addition of RVT. ^aP < 0.05, ^bP < 0.01.

Figure 5 Sequential change of luciferase activity of OS6 cells after addition of interferon (IFN). A: IFN was added for the indicated duration and the ratio to the luciferase activity at time 0 was shown. Statistical significance (^aP < 0.05, ^bP < 0.01) is shown below: at 24 h 0 vs 1^a, 2^b, 4^b, 10^b and 20^b; at 48 h, 0 vs 1^b, 2^b, 4^b, 10^b and 20^b; 1 vs 2^b, 4^b, 10^b and 20^b; 20 vs 2^b, 4^b and 10^b; at 72 h, 0 vs 1^b, 2^b, 4^b, 10^b and 20^b; 1 vs 2^a; 1 vs 4^b, 10^b and 20^b; 2 vs 4^b, 10^b and 20^b; 4 vs 10^b and 20^b; 10 vs 20^b; B: Luciferase activity after addition of RVB and IFN for 72 h was shown as the ratio to that without antiviral agents. ^aP < 0.05, ^bP < 0.01.

Figure 6 The enhancing effect of RVT on replication of HCV RNA, even when treated with ribavirin (RBV) and IFN. RVT was simultaneously added to RBV or IFN. A: The ratio was calculated as the ratio of luciferase activity with RVT to that without RVT. ^bP < 0.01 vs RVT 0; B: The same procedure was applied in AXN.

Figure 7 The comparative effect of RBV (A), RVT (B) and AXN (C) on the luciferase activity of IFN-treated cells. Cells were simultaneously treated with 1 U/mL of IFN and the indicated concentrations of RBV, RVT and AXN were added with IFN.