Synergistic effects by combination of ganciclovir and tricin on human cytomegalovirus replication in vitro

•Combination treatment with GCV and tricin to HCMV replication was studied.•We found strong synergistic effects on HCMV replication by GCV and tricin.•Tricin is a novel compound for combination therapy with GCV against HCMV replication.

It has been demonstrated as the first report that combination treatment with ganciclovir (GCV) and tricin (4′,5,7-trihydroxy-3′,5′ -dimethoxyflavone), a derivative of Sasa albo-marginata, after human cytomegalovirus (HCMV) infection has synergistic effects on both infectious virus production and HCMV DNA synthesis in the human embryonic fibroblast cell line MRC-5. In this paper, we examined the anti-HCMV effects of GCV plus various concentrations of tricin, and tricin plus various concentrations of GCV in MRC-5 cells. We found that expression of the HCMV UL54 gene was significantly inhibited by combination of GCV with tricin when compared with GCV mono-treatment. These results suggest that tricin is a novel compound for combination therapy with GCV against HCMV replication. In addition, reduced-dose combination therapy may provide a direction for treatment in patients with HCMV infection while reducing drug toxicity.