Virofree, an Herbal Medicine-Based Formula, Interrupts the Viral Infection of Delta and Omicron Variants of SARS-CoV-2

Abstract

Coronavirus disease 2019 (COVID-19) remains a threat with the emergence of new variants, especially Delta and Omicron, without specific effective therapeutic drugs. The infection causes dysregulation of the immune system with a cytokine storm that eventually leads to fatal acute respiratory distress syndrome (ARDS) and further irreversible pulmonary fibrosis. Therefore, the promising way to inhibit infection is to disrupt the binding and fusion between the viral spike and the host ACE2 receptor. A transcriptome-based drug screening platform has been developed for COVID-19 to explore the possibility and potential of the long-established drugs or herbal medicines to reverse the unique genetic signature of COVID-19. In silico analysis showed that Virofree, an herbal medicine, reversed the genetic signature of COVID-19 and ARDS. Biochemical validations showed that Virofree could disrupt the binding of wild-type and Delta-variant spike proteins to ACE2 and its syncytial formation via cell-based pseudo-typed viral assays, as well as suppress binding between several variant recombinant spikes to ACE2, especially Delta and Omicron. Additionally, Virofree elevated miR-148b-5p levels, inhibited the main protease of SARS-CoV-2 (Mpro), and reduced LPS-induced TNF-α release. Virofree also prevented cellular iron accumulation leading to ferroptosis which occurs in SARS-CoV-2 patients. Furthermore, Virofree was able to reduce pulmonary fibrosis-related protein expression levels in vitro. In conclusion, Virofree was repurposed as a potential herbal medicine to combat COVID-19. This study highlights the inhibitory effect of Virofree on the entry of Delta and Omicron variants of SARS-CoV-2, which have not had any effective treatments during the emergence of the new variants spreading.

Virofree Associates with the Modulation of Gut Microbiomes and Alleviation of DSS-Induced IBD Symptoms in Mice

“…Virofree is composed of quercetin, hesperidin, genistein, daidzein, and resveratrol, compounds that possess potent antioxidant and anti-inflammatory activities. Based on previously unreported clinical observations, the pharmacodynamic properties of Virofree include prevention and therapeutic interventions for influenza, adjunct treatment for radiotherapy/chemotherapy, reduction in the frequency of asthma attacks, anti-inflammatory effects, and facilitation of genotoxic repair . Consuming a diet rich in various phytochemicals such as polyphenols, polymethoxyflavones, stilbenoids, and flavonoids can have beneficial effects that include modulation of the intestinal microbiota and prevention of various inflammatory diseases. − Moreover, there is increasing evidence concerning the beneficial effects of plant extracts in managing colitis. − …”

“…The sample diets were administered as a pretreatment 1 week prior to the commencement of the experiment. The dosage of Virofree was based on previous studies . Throughout the experimental period, the mice were regularly assessed for body weight and the disease activity index (DAI) that was determined based on clinical manifestations including weight loss, stool consistency, and the presence of hematochezia.…”

Repurposing Astragalus Polysaccharide PG2 for Inhibiting ACE2 and SARS-CoV-2 Spike Syncytial Formation and Anti-Inflammatory Effects

“…The assay was performed as previously described [ 24 ]. Briefly, on a six-well plate, donor BHK-21 cells were seeded at 4 × 10 5 cells/well and transfected with both EGFP and S plasmids (Wuhan strain) at a ratio of 1:5 using Lipofectamine™ 2000 Transfection Reagent (Invitrogen, cat.…”

“…Images of five fields of EGFP-positive cells were randomly taken as previously described, indicating fusion efficiency. The quantification of binding efficiency and syncytial cell formation was performed as previously described [ 24 ].…”

“…Enzyme-linked immunosorbent assay (ELISA) was performed to examine the ability of PG2 to intervene in the ability of wild-type trimeric SARS-CoV-2 S protein (Wuhan strain) or variants (α, β, γ, δ) to bind to biotinylated human ACE2 recombinant protein. The experimental procedures were performed as previously described [ 24 ]. Briefly, each well of a 96-well plate was coated overnight at 4 °C with 500 ng/mL of S protein (Cat.…”