Antiviral effect of Epimedium koreanum extract

Epimedium koreanum Nakai (EKN) [Berberidaceae] has been extensively used in traditional Korean and Chinese medicine to treat a variety of diseases, such as infertility, impotence, neurasthenia, cardiovascular diseases, amnesia, lumbago, arthritis, various immune-modulatory problems, aphrodisiac, and anti-rheumatic [1 – 3]. Despite of EKN's immune modulatory potential [4], its antiviral properties and mode of action have not been completely investigated. In the present study, the broad spectrum of antiviral efficacy of EKN water extract was evaluated in vitro, and moreover, the protective effect against divergent influenza A subtypes was determined using BALB/c mice. EKN at 100 ug/ml markedly reduced the replication of Influenza A Virus, Vesicular Stomatitis Virus, Herpes Simplex Virus and Newcastle Disease Virus in RAW264.7 and HEK293T cells. EKN at 100 ug/ml induced the secretion of type I IFN and pro-inflammatory cytokines and the subsequent stimulation of antiviral state in the cells. Among various components in the extract, quercetin was confirmed to have striking antiviral properties. The oral administration of EKN at 20 mg per head exhibited preventive effects on BALB/c mice infected with 5 MLD50 influenza A subtypes (H1N1, H5N2, H7N3 and H9N2). Therefore, EKN water extract plays roles as immune-modulators in innate immune response, and may be potential candidates for therapeutic treatments against diverse viruses in animal and humans.

Acknowledgements: This work was supported by a grant (Grant No. K12050) awarded to the Korean Institute of Oriental Medicine by the Ministry of Education, Science and Technology (MEST), Korea and the Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea (Grant No. 112013033SB010).

Keywords: Epimedium koreanum Nakai, herbal medicine, antiviral effect, immune response.

References:

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