Teaching old drugs new treatments
The researchers found that some common drugs were able to prevent a particular virus from infecting cells by blocking the ion channels that regulate potassium levels.
Specifically, drugs that were able to inhibit the potassium ion channels were effective against the Bunyamwera virus – a virus family including human pathogens such as Hantaviruses and Crimean-Congo haemorrhagic fever virus, which is increasing in prevalence in Mediterranean countries, and is endemic in Africa, the Middle East, and some Asian countries.
The researchers found that by blocking the ion channels affected the bunyaviruses’ ability to infect cells.
"This is a breakthrough finding since bunyaviruses are considered as emerging pathogens with the potential to establish a global disease range with massive importance in healthcare, animal welfare and economics,” said Dr. Jamel Mankouri, of the School of Molecular and Cellular Biology at the University of Leeds.
"Being able to block these ion channels is an important first step in understanding how we can stop these viruses spreading and causing human disease."
The research is also important because very few antiviral drugs have made it to clinical use in the last 15 years, mainly because of cost, according to Dr. John Barr, who helped develop the idea at Leeds
"Taking a drug that has already been proven to be safe, and using it to target a different condition or infection - a process known as drug repurposing - bypasses this expensive and time-consuming stage,” he added.
"There are many drugs targeting ion channels that are currently in use for a wide range of conditions. Our work shows that some of these might be suitable to treat virus infections."
The team also tested the Hazara virus, used as a model for CCHFV, and Schmallenberg virus. The drugs used in the research included the anti-psychotic haloperidol, the anti-depressant fluoxetine, and a local anaesthetic, bupivacaine.
A live virus system was used to compare how the viruses were affected by each of the drugs. While the Schallenberg virus was not affected in the same way as the bunyavirus, it shows that each virus may target a specific channel type in order to create an environment in which to grow.
Dr. Alain Kohl, head of reserach at the University of Glasgow, explained: "If existing drugs are confirmed to be effective against known members of a particular virus family, this opens up the possibility of using these 'off-the-shelf' treatments in a rapid response against dangerous new related virus strains that emerge."
