A new study suggests that a drug known as nitisinone can make human blood lethal to mosquitoes that carry malaria. (Image credit: Smith Collection/Gado via Getty Images)
A new study has shown that a drug approved to treat rare genetic disorders can also make human blood toxic to mosquitoes that spread malaria.
Nitisinone is currently used to treat two genetic disorders: tyrosinemia type 1 and alkaptonuria. The drug works by inhibiting the enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD), which is involved in a process known as the tyrosine detoxification pathway. By blocking this enzyme, nitisinone prevents the accumulation of harmful substances in the bodies of patients suffering from these genetic disorders.
However, recent studies have also shown that blood-sucking insects, including Anopheles mosquitoes that carry the Plasmodium parasite that causes malaria, require HPPD to digest their blood meals.
A new study published March 26 in Science Translational Medicine presents preliminary data showing that treating human blood with nitisinone makes it deadly to Anopheles mosquitoes. By interfering with an enzyme called HPPD, the drug effectively makes it impossible for mosquitoes to detoxify the amino acid tyrosine in the blood, causing them to die after feeding.
The scientists who conducted the study hope that nitisinone could potentially be adapted as a new way to combat malaria. Developing additional methods of control could be especially useful given that mosquitoes are becoming increasingly resistant to traditional insecticides used to kill them.
Still, nitisinone is not a “silver bullet,” said study co-author Alvaro Acosta-Serrano, a professor of molecular parasitology and vector biology at the University of Notre Dame in Indiana. The drug will not prevent people from becoming infected with malaria or cure those already infected, he told Live Science. But nitisinone may reduce transmission of the disease by reducing the population of mosquitoes that carry the Plasmodium parasite, he explained.
In the new study, the researchers conducted a series of lab experiments to determine the minimum concentration of nitisinone needed to kill Anopheles mosquitoes. Using a lower dose could help reduce the risk of possible side effects in people taking the drug, as well as reduce the likelihood that mosquitoes will become resistant to it over time, Acosta-Serrano said.
The researchers found that when Anopheles mosquitoes were given blood containing nitisinone, the insects died. This was observed regardless of whether the mosquitoes were resistant to traditional insecticides.
Sourse: www.livescience.com
