Balanced cytokine upregulation by diluted ethanolic extract of Bryonia alba in Delta SARS-CoV-2 Spike protein RBD-induced pathogenesis in Gallus gallus embryo

Bull Natl Res Cent. 2022;46(1):169. doi: 10.1186/s42269-022-00856-3. Epub 2022 Jun 13.

Abstract

Background: Bryonia alba extract is a well-known drug which is being utilized as phytomedicines and homoeopathic preparations since more than two centuries. This medicine is frequently used in clinical practice for flu-like conditions, respiratory tract infections, and gastrointestinal diseases, as evidenced by old literature and historical records. The plant contains Bryonicin, Bryonolic acid, Bryodin, Cucurbitacin, etc. The alkaloids in Bryonia alba have been discovered to be a powerful heme-oxygenase-1 inhibitor, which could help reduce oxidative stress during SARS-CoV-2 pathogenesis. During three waves of SARS-CoV-2, extracts of Bryonia alba were used; however, the actual scientific explanation for its mechanism of action is still unknown. In this experiment, we studied cytokine changes by diluted Bryonia alba extract in Delta SARS-CoV-2 spike protein RBD-induced pathogenesis, in fertilized chick (Gallus gallus domesticus) embryos.

Results: The recombinant Delta SARS-CoV-2 spike RBD protein was inoculated in 14-day-old chick (Gallus gallus domesticus) embryos along with control, pre-, and post-treatment sets with diluted Bryonia extract. After 48 h, allantoic fluids were collected and stored at - 20 °C for study of different cytokines. Histological changes of the liver were also studied in each animal. Diluted Bryonia extract upregulated IFN-α and IL-10 markedly. In pre-treatment set, IFN-α, IL-8, IL-10, and IL-1β were markedly decreased, while in the post-treatment set IL-6, IL-10, IL-8, and TGFβ1 were significantly decreased, with a tendency of more anti-inflammatory surge than pro-inflammatory cytokines.

Conclusions: This experiment indicated an immunomodulatory role of diluted ethanolic extract of Bryonia particularly in the post-treatment set, decreasing pro-inflammatory cytokines with beneficial effect.

Keywords: Bryonia alba; Chick embryo; Immunomodulatory action; SARS-CoV-2.