Mechanism of Anti-rotavirus Synergistic Activity by Epigallocatechin Gallate and a Proanthocyanidin-Containing Nutraceutical

Abstract

Epigallocatechin gallate (EGCG) of green tea and the nutraceutical CystiCran-40 (containing 40% proanthocyanidins) of the cranberry plant have been associated with antiviral activity. The purpose of this work was to determine the mechanism of antiviral synergy between each compound. Coliphage T4II (phage T4) and the rotavirus strain SA-11(RTV) were used as model virus systems. Individual and combined flavonoids structural and molecular weight analyses were performed by NMR and HPCL/MS, respectively. A suboptimal concentration of EGCG or C-40 alone or in combination reduced phage infectivity by ≤10%. Similarly, EGCG (30 µg/ml) and C-40 (25 µg/ml), respectively, reduced RTV titers by 3 and 13%. However, RTV titers were reduced by 32% (p < .05) with both flavonoids used in combination. RTV was not recognized in host cells by electron microscopy 24-h post-inoculation. NMR and HPLC/MS findings revealed significant structural and potential changes in molecular weight of the flavonoids in complex.

Phytochemicals as Antiviral Agents: Recent Updates

“…Several mechanisms have been adopted by phytochemicals to inhibit viral replication. For instance, epigallocatechin gallate (EGCG) inactivates the host enzyme or viral enzyme which promotes the growth of the virus, such as RNA polymerase, protease, and reverse transcriptase (Lipson et al 2017). Another mechanism adopted by flavonoids is to inhibit phosphorylation of protein, which restricts the replication of HIV (Ahmad et al 2015).…”

“…EGCG is one of the flavonoids, and is an important component of green tea. It has been reported to have antiviral activity against rotavirus strain SA-11 (Lipson et al 2017). Zakaryan et al reported baicalein, another flavonoid (flavone), having antiviral activity against human cytomegalovirus (HCMV).…”

Effect of a Δ9-tetrahydrocannabinol (THC)/cannabidiol (CBD) formulation on cell monolayer viability and mitochondria integrity: Significance of the drug carrier/delivery system

“…As a fi nal point, it was not our intension to duplicate earlier studies addressing those adverse effects on MT bioenergetics imposed to either one or more cannabinoid constituents [6][7][8][38][39][40][41][42]. Our interest however, was directed to those potential morphologic aberrations of the MT and early stage dissolution of organelle membrane integrity within our enteric epithelial cell culture system.…”

“…Shell vials were inoculated with concentrations of homogenized THC/CBD ranging from 50 to 125 μg/ml MM and incubated at 37 o C for 72-h. Cover slips were washed with PBS, fi xed with methanol, removed using a hypodermic needle, and affi xed to glass slides using Permount histological glue (Lipson et al, 2017). The HT-29 monolayers were fi xed in methanol, immunostained with antibody clone 113-1, and incubated for a period 37 O C for 30 min.…”

Characterization and Potential Antidiabetic Activity of Proanthocyanidins from the Barks of Acacia mangium and Larix gmelinii

“…e electrophilic intermediates can be trapped by nucleophilic reagents to generate analyzable adducts (Figure 1) [4]. Additionally, avonoids often exhibit synergistic e ects on biological activities [23]. Based on the inhibitory e ects of epicatechin against α-glucosidase, the result of DP not playing the predominant role for α-glucosidase inhibition was proved, which may also be a ected by the nature of inter avanyl bonds of PAs.…”