Topical cream-based oxyresveratrol in the treatment of cutaneous HSV-1 infection in mice

Anti-herpes simplex virus (HSV) activities of oxyresveratrol in vitro and topical administration in cutaneous HSV-1 infection in mice were examined. The inhibitory concentrations for 50% plaque formation (IC50) of oxyresveratrol against HSV-1 clinical isolates and HSV-2 clinical isolates were 20.9–29.5 and 22.2–27.5 μg/ml, respectively. In topical administration in cutaneous HSV-1 infection in mice, 2.5%, 5%, 10% and 20% oxyresveratrol in cream vehicle applied three times daily for 7 days after infection were evaluated and 10% and 20% oxyresveratrol cream were significantly effective in delaying the development of skin lesions and protection from death (P < 0.01). The concentration of 10% oxyresveratrol in cream was significantly more effective than that of 30% oxyresveratrol in vaseline applied three times daily (P < 0.01). Oxyresveratrol cream at 20% was as effective as 5% ACV cream applied three times daily (P < 0.01). Both 10% and 20% oxyresveratrol cream were as effective as that of 5% ACV cream applied two times daily (P > 0.05). Therapeutic efficacy of oxyresveratrol in cream vehicle was dose-dependent and the maximum efficacy observed on day 6 after infection was shown at 10% oxyresveratrol in cream applied three times daily. The frequency of application of 10% oxyresveratrol cream at three, four and five times daily was as effective as that of 5% ACV cream applied five times daily (P > 0.05). These results demonstrated that topical administration of oxyresveratrol in novel cream vehicle reduced the concentration of oxyresveratrol to 10% and was suitable for cutaneous HSV infection.