Suppression of influenza B virus replication by sakuranetin and mode of its action

Abstract

This study aimed to investigate in vitro the anti-influenza B/Lee/40 virus effect of sakuranetin and mode of its action. The sakuranetin exhibited potent antiviral activity against influenza B/Lee/40 virus, reducing the formation of a visible cytopathic effect, with a 50% inhibitory concentration (IC ) of 7.21 μg/ml and no cytotoxicity at a concentration of 100 μg/ml, and the derived therapeutic index (TI) was >13.87. Oseltamivir showed weak anti-influenza B/Lee/40 virus activity with IC of 80.74 μg/ml, 50% cytotoxicity concentration of >100 μg/ml, and TI of >1.24. Sakuranetin also showed effective inhibitory effects when added at the viral attachment, entry, and postentry steps. Moreover, sakuranetin effectively inactivated influenza B/Lee/40 virus infection in dose- and temperature-dependent manners. Sakuranetin indicated an inhibitory effect in viral RNA synthesis in the presence of 100 μg/ml of sakuranetin. Overall, this research revealed that sakuranetin could inhibit influenza B/Lee/40 virus replication and that sakuranetin may be involved in the virus attachment, entry, and postentry. Therefore, sakuranetin is a good candidate for a chemopreventive agent for influenza virus-related diseases.

A Review on Sources and Pharmacological Aspects of Sakuranetin

“…Sakuranetin also has an antiviral activity. Kwon et al [70] proved that sakuranetin has a strong activity against the influenza B/Lee/40 virus. This activity was shown to be dose-and temperature-dependent.…”

Production of (2S)-sakuranetin from (2S)-naringenin in Escherichia coli by strengthening methylation process and cell resistance

“…(2 S )-Sakuranetin (7- O -methylated (2 S )-naringenin) is a 7- O -methylated flavonoid that is present in many plants, such as Oryza sativa [ 1 ], orange peel [ 2 ], and Piper lanceifolium Kunth [ 3 ]. It has been proved to have anti-inflammatory [ 4 ] (such as inhibiting 5ARII [ 5 ]), antimutation, anti- Helicobacter pylori [ 6 ], antidiabetic [ 7 ], antiviral (inhibiting viruses such as the influenza B/Lee/40 virus [ 8 ] and human rhinovirus 3 [ 9 ]), and anticonvulsant [ 10 ] properties. It can also exert protective effect on the brain, and can be used to treat Alzheimer's disease [ 11 ].…”

New perspectives on natural flavonoids on COVID‐19‐induced lung injuries

“…These authors showed that sakuranetin could similarly act as an immunomodulatory compound since it was reported that this treatment in mice could modulate the macrophage profile. In addition, sakuranetin has an inhibitory effect in viral RNA synthesis, effective in the inactivation of the influenza B/Lee/40 virus, and could be a good candidate for treating diseases related to the influenza virus (Kwon, Ji, Yim, Kim, & Choi, 2018).…”