SINGAPORE, Oct. 24 (Xinhua) -- Scientists at Singapore's Nanyang Technological University (NTU) have created a peptide that targets the Zika virus at its weak spot, which may lead to the birth of a future drug that could prevent viral infections in the brain.
This peptide (a compound consisting of amino acids), by working to attack the membrane that surrounds Zika's viral particle, can hold the key in becoming a future drug that acts directly on viral infections in the brain, the research team, which is led by NTU's Associate Professor Nam-Joon Cho, told the media on Wednesday.
Under the traditional approach, antiviral drugs prevent viruses from replicating, though they can quickly become outdated and ineffective as viruses mutate rapidly.
In contrast, the engineered peptide can still be potentially effective even if the Zika virus tries to mutate, according to Cho, as the peptide is able to differentiate between Zika viral membranes and the cell membranes of mammals, as the former are smaller and more curved, while the latter are larger and flatter.
Likening it to how "a pin pricks a balloon," Cho of NTU's School of Materials Science and Engineering said, "the peptide pricks a hole in the viral membrane. Prick enough holes, and the virus will be ruptured."
Scientists believe that as all flaviviruses have virus particles that are around 40-55 nanometers in diameter and are enveloped by a lipid (a component of fats) membrane, the peptide engineered by the NTU scientists has great potential to work against these wide range of membrane-enveloped viruses.
Lab tests showed that after mice were infected with a lethal dose of the Brazilian Zika virus sample, 10 out of 12 treated mice survived. In contrast, all untreated mice died within a week post-infection.
More importantly, the peptide was able to cross the nearly impenetrable barrier between the blood and the brain, thus directly treating viral infection in mouse brains and protecting them against Zika injury. This is especially critical as Zika targets the brain and central nervous system.
Done in collaboration with the Federal University of Minas Gerais in Brazil and Ghent University in Belgium, the study spanned over six years and combined different fields of study like materials engineering, antiviral drug development and pharmacology. The team published their findings in the peer-reviewed journal Nature Materials on Oct. 22.
In 2004, Cho developed the first antiviral peptide that works against viral membranes in laboratory tests. Over the years, he and the team came up with this engineered peptide.
The Zika virus is transmitted by the Aedes mosquitoes and infections during pregnancy are linked to birth defects such as microcephaly, a condition in which a baby is born with an abnormally small head and brain.
Currently, there are no vaccines for the Zika virus, while available medicines only alleviate symptoms such as fever and pain.
