The Antiviral Activity of Kaempferol Against Pseudorabies Virus in Mice

Abstract

Background: Pseudorabies virus (PRV), a member of the neurotrophic Alphaherpesviruses, is one of the most important pathogens that harm the global pig industry. Accumulated evidence indicated that PRV could infect humans under certain circumstances, inducing severe clinical symptoms such as acute human encephalitis. Currently, there are no antiviral drugs to treat PRV infections, and vaccines available only for swine could not provide full protections. Thus, new control measures are urgently needed. Results: In the present study, kaempferol exhibited anti-PRV activity in mice through improving survival rate by 22.22% at 6 days post infection (dpi) which is higher than acyclovir (Positive control) with the survival rate of 16.67%, and in the infected-untreated group the survival rate was 0%. Kaempferol could inhibit the virus replication in the brain, lung, kidney, heart and spleen, especially in the brain the viral gene copies were reduced by over 700-fold, which is further confirmed by immunohistochemical examination. The tissue lesions induced by PRV infection in these organs were also alleviated. The expressions of the early genes EPO and TK in the brain were significantly inhibited by kaempferol. The expression of latency-associated transcript (LAT) were also inhibited in the brain, which suggested kaempferol could inhibit the PRV latency. Kaempferol-treatment could induce higher levels of IL-1β, IL-4, IL-6, TNF-α and IFN-γ in the serum at 3 dpi which were then declined to normal levels at 5 dpi, suggesting that kaempferol could exert anti-PRV activity through regulation of the immune function.Conclusions: These results suggest that kaempferol is expected to be a new alternative control measure for PRV infections.

Effects of Propolis on Infectious Diseases of Medical Relevance

“…As described in each work, most of the molecules identified in each propolis are compounds of phenolic origin. Some of these have been reported as having the ability to stimulate antiviral responses in in vitro and in vivo models, promoting the production of interferons as well as the activation of cytotoxic T lymphocytes and natural killer cells [195][196][197][198][199]. This supports the use of propolis as a source of new molecules with antiviral effects and an alternative to complement the treatment of these diseases.…”