Assessment of Traditional Chinese Herbal Medicine Plant Extracts' Potential to Inhibit Activity of Herpes Simplex Virus Type 1

Abstract

Herpes simplex virus type 1 (HSV-1) is associated with oral and genital lesions as well as more serious, even fatal, infections in immunocompromised patients or when transmitted to infants. Currently, there is no cure or preventative vaccine available for HSV. Acyclovir is used for treatment of HSV infections but resistance to this drug is common in immunocompromised patients and severe side effects can develop when used by pregnant mothers and infants. The lack of a preventative option and limited treatments demonstrate the need for more effective treatment measures. Many studies have demonstrated the effectiveness of TCM plants against various illnesses, but little has been done to evaluate TCM plant extracts against HSV-1. This study tested 51 TCM extracts from 13 different plants for their potential to inhibit HSV-1. Extracts were separated into fractions and dissolved in the solvents petroleum ether, ethyl acetate, 95% ethanol or water. Vero cells were used to evaluate plant extracts for anti HSV-1 activity. Extracts were combined with virus and protection of cells was determined by using PrestoBlue, a cell viability fluorescent dye. Extracts were tested for toxic effects on host cells and were diluted to non-toxic levels prior to antiviral testing. A total of 51 extracts from 13 different plants were tested. Out of these 51 extracts, 14 were found to have at least 50% viral inhibition with 3 of them showing above 95% viral inhibition. The ultimate goal of this study is to isolate and identify a pure compound that can combat HSV-1. ii