Extract from the bark of the neem tree may help treat and reduce the spread of SARS-CoV-2, the virus that causes COVID-19, according to a study led by researchers at the Indian Institute of Science Education and Research (IISER) Kolkata.
The neem tree, indigenous to India, has been used for thousands of years for its anti-parasitic, anti-bacterial and antiviral properties, the researchers said.
The bark extract has helped treat malaria, stomach and intestinal ulcers, skin diseases and many other diseases, they said.
The latest study, published recently in the journal Virology, shows that components of neem bark may target a wide range of viral proteins, suggesting its potential as an antiviral agent against emerging variants of coronaviruses, including SARS-CoV-2.
"The goal of this research is to develop a neem-based medication that can reduce the risk of serious illness when someone is infected with coronaviruses," said study co-author Maria Nagel, a professor at the University of Colorado School of Medicine, US.
"We hope that scientists won't have to continuously develop new therapies every time a new SARS-CoV-2 variant emerges," she said.
Just like how people take penicillin for strep throat, the researchers envision taking the neem-based drug for COVID-19, allowing them to resume their normal lives without fear of hospitalisation and death.
The scientists investigated the impact of the bark extract against coronaviruses in their laboratories.
Researchers at IISER Kolkata tested the extract in animal models and showed that it had antiviral properties against coronavirus.
Using computer modelling, the researchers predicted that neem bark extract will bind to the SARS-CoV-2 spike protein at various locations, preventing virus entry to host cells.
The spike protein is used by the SARS-CoV-2 virus to enter and infect cells.
Nagel's lab at the University of Colorado tested the neem bark extract in SARS-CoV-2 human lung cells.
The extract proved as effective as a preventive drug for infection and also decreased virus replication and spread after infection.
"The next step in our research is to identify the specific components in neem bark extract that are antiviral. Because these components bind to various regions of SARS-CoV-2, we believe that it will be effective on emerging variants with spike mutations," said Nagel.
"We will then determine the formulation of dosage for an antiviral drug to treat coronavirus infections," she said.
The findings could guide new antiviral therapeutic efforts to combat the ongoing pandemic while holding out the promise for treating new coronavirus strains, the researchers added.