The Efficacy of Antiviral Components from Plant Products against Herpes Simplex Virus Type 1

HSV-1 is the leading transmittable cause of blindness in the United State and the developed countries of the world. HSV-1 establishes lifelong latency in the TG and is associated with high morbidity and mortality in humans worldwide. Currently, there is no method available to eliminate latent HSV-1 from an infected individual. Several FDA approved anti-HSV-1 drugs, such as Acyclovir, Valancyclovir, Famcyclovir and Pencyclovir are available for treatment. However, widespread use of these nucleoside analogues produces drug resistant HSV-1 mutants that cause more severe infections. Also these drugs have no ability to prevent latency/recurrences. To find a cure for this devastating disease, cost effective natural antivirals that prevent resistance development with reduced toxicity are of immediate need. A wide variety of plants are being studied as a source of natural products that can result in the development of novel drugs. Several compounds from these sources have shown high levels of antiHSV-1 activity. However, development of antivirals from these herbal sources has not been completely explored. Recently, we have tested the efficacy of partially purified component(s) from regular and pearl garlic (PG) against HSV-1 in vitro. The compound(s) from pearl garlic extracts have shown strong antiviral efficacy against wild type HSV-1 and ACV resistant HSV-1 mutants as compared to regular garlic. About 70% of the ACV resistant TKHSV-1 replication was inhibited by the isolated components from PG. Active constituents from this plant product may provide useful lead to the development of new and effective antiviral agent(s) against HSV-1. In the current review, the findings from this study along with some of the most promising compounds from herbal sources having anti-HSV-1 activity will be described.