Chikungunya!!! The word chikungunya means ‘to walk bent’. Once, it was considered as a disease of tropics. But now cases have been spotted in more than one-quarter of the countries on earth. Currently, neither there is any drug to treat chikungunya, nor there are any vaccines to prevent it. But Indians can feel proud. A team of researchers at the Indian Institute of Technology (IIT) Roorkee has climbed the first step of success. They’ve discovered a small molecule that has good antiviral activity against chikungunya virus.
The study was conducted by a team led by Prof. Shailly Tomar from the Department of Biotechnology, IIT Roorkee. The team had earlier identified two small molecules — Pep-I and Pep-II — for their inhibitory activity, using structure-based studies of chikungunya virus, specific nsP2 protease. These protease inhibitors have already been using successfully against HIV and hepatitis C virus.
The researchers report that among these two molecules, Pep 1 has superior antiviral activity against chikungunya virus. This study has been mentioned in the journal Biochimie. The molecule was found effectively bind to the protein of the chikungunya virus (nsP2 protease). The researchers also discovered that this molecule stops the virus from replicating. This led to a hypothesis that any molecule that inhibits nsP2 protease should have antiviral activity. To test the hypothesis, they carried out antiviral studies using cell lines. Prof. Tomar, who led the research says that “The studies confirmed that both molecules had significant ability to kill the virus. The Pep-I molecule was very efficient in killing the virus — 99% reduction in virus at 5 microMolar”.
The paper of this study was written by Harvijay Singh and Rajat Mudgal from the Department of Biotechnology at IIT Roorkee. About the research, they say that “When 10 microMolar of Pep-I was used no viable virus could be detected in the culture.The antiviral activity was tested by adding the molecules directly into the virus culture. The two molecules also reduced the viral RNA thus confirming the antiviral activity. Also, “We found even when the concentration of the two molecules was less than 50 microMolar, they were able to effectively inhibit the protease. Generally, when less than 50 microMolar concentration produces good enzyme inhibition it is considered good in terms of potency and effectiveness.”
As the research proved that the molecule has antiviral capacity against chikungunya virus, what the team wanted to know was whether the molecule specifically inhibits only the chikungunya virus. To test, they used Sindbis virus, the model virus of the genus alpha-virus to which chikungunya belongs. They found that the molecule has no antiviral activity against other viruses than chikungunya.
The researchers are not done yet. They’re aiming at improving the potency of the inhibitors. Anyhow if the research turns out to be successful, It can be considered as a major achievement in the field of science and medicine. Earlier, in September 2017, IIT Roorkee has been in news for conducting a research for finding a drug to treat chikungunya.
Credits : The Hindu