Abstract
Antiviral activity in vitro and therapeutic efficacy of polyphenols including catechin from green tea (Camellia sinensis) were evaluated in mice infected with herpes simplex virus (HSV) and influenza virus (IFV). The extract concentrations that inhibited plaque formation of HSV-1, HSV-2, and IFV by 50% were 29.24 ± 2.97, 22.19 ± 5.64, and 30.50 ± 2.40 μg/ml, respectively. Mice administered polyphenols (25 and 50 mg/kg/dose) intraperitoneally 1 h before and twice daily after virus inoculation exhibited significant delays in the development of herpetic skin lesions (P<0.05), while oral administration of 50 mg/kg/dose or intraperitoneal administration of 5 mg/kg/dose of polyphenols twice daily failed to delay the development of skin lesions. These results demonstrated that polyphenols showed therapeutic anti-HSV activity after intraperitoneal administration but not oral administration in cutaneous HSV infection in mice. In contrast, polyphenols did not show significant therapeutic efficacy in IFV-infected mice in spite of anti-IFV activity in vitro. Although polyphenols from green tea have antiviral activity against HSV and IFV in vitro, antiviral activity was not absorbed orally, while intraperitoneal administration showed anti-HSV therapeutic activity but not anti-IFV activity in IFV-infected mice.
