Combined Antiinfluenza Virus Effect of a Plant Preparation and a Bacterial Protease Inhibitor

ABSTRACT

Influenza is a major public health problem because of its wide spread, high morbidity rate and considerable social and economic implications. The combined application of natural viral inhibitors may be used successfully to potentate their antiviral efficacy and may enable dose reduction. The collective virus-inhibitory effects of a polyphenol extract from Geranium sanguineum L. (PC) and a proteinaceous protease inhibitor, produced by Streptomyces sp. 34–1 (SS 34–1) have been investigated on the reproduction of influenza virus A/Germany/34, strain Rostock (H7N1) in MDCK cell cultures. The simultaneous application of SS 34–1 and PC in doses, which by themselves do not suppress significantly viral replication, led predominantly to antagonistic virus-inhibitory effects. Further the combined application of these viral inhibitors was tested in the murine experimental influenza virus infection (EIVI). Predominantly synergistic effects were achieved. The results support the efficacy of combined chemotherapy; however to achieve a synergistic enhancement of the virus-inhibitory effect it is essential to precisely select the doses of the individual components in the combinations

Keyword:

• anti-influenza virus effect
• polyphenol extract
• protease inhibitor