A peptide isolated from the skin of a frog endemic to India's Western Ghats could neutralise Zika and dengue viruses, a study reveals1.

A team of international researchers has discovered that the peptide blocks the activity of all Zika strains quickly and could be a promising antiviral compound for treating infections caused by Zika and dengue.

Zika and dengue viruses, transmitted to humans through mosquito bites, cause severe infections. The Zika virus also damages foetal brains through infected pregnant women. An existing vaccine against the Zika virus is not efficient.

In search of an effective therapy, the scientists, including researchers from the Rajiv Gandhi Centre for Biotechnology in Kerala, India, isolated and screened peptides from the skin of the golden frog Indosylvirana aurantiaca . They identified 12 peptides that decrease the infectivity of the Zika virus.

One of these peptides was the most effective and non-toxic to human red blood cells even at high concentrations. The peptide, named ‘Yodha’ (warrior in Sanskrit) by the reserachers, neutralised Zika viruses within the first five minutes of exposure. It prevented the entry of the viruses into specific host cells from an African monkey.

The peptide, part of a host’s innate immune system, blocked viral activity and reduced virus numbers inside the host cells, possibly by disrupting their structure, the researchers say.

The peptide successfully reduced the load of Zika viruses in mice. It also efficiently inhibited the growth of all four strains of dengue viruses.

References

1. Lee, S. H. et al. The amphibian peptide Yodha is virucidal for Zika and dengue viruses. Sci. Rep. 11:602 (2021)