Malaria could soon be combated using a new compound that destroys the parasite that causes the often-fatal disease.
Malaria kills one child every minute in Africa, and the parasite responsible for the illness quickly mutates when new treatments are developed. Because of this ability, medical researchers have been striving to develop a means of quickly killing the microorganism before populations could mutate into forms resistant to the drug.
Plasmodium falciparum parasites are carried by mosquitoes, and once they enter the human bloodstream, the tiny organisms invade red blood cells. Malaria took the lives of 627,000 people in 2012, according to the World Health Organization.
Medical researchers from St. Jude Children's Research Hospital led the investigation that developed this new treatment from a previous study the group performed.
The new drug, (+)-SJ733, kills all of the Plasmodium parasites in mice tested during the study within 48 hours, before resistance can build. In experiments with rodents, 80 percent of the parasites disappeared within 24 hours of treatment. The compound works by fooling the body's natural immune system into attacking infected blood cells, while leaving healthy cells unaffected.
The ATP4 protein in the parasite normally regulates the sodium balance in the microorganism. Researchers discovered (+)-SJ733 affects this protein, altering the internal sodium balance of the parasite, killing the disease-carrying organism.
"Our goal is to develop an affordable, fast-acting combination therapy that cures malaria with a single dose. These results indicate that SJ733 and other compounds that act in a similar fashion are highly attractive additions to the global malaria eradication campaign, which would mean so much for the world's children, who are central to the mission of St. Jude," R. Kiplin Guy, Ph.D., chair of the Department of Chemical Biology and Therapeutics at St. Jude, said.
Future research includes safety trials for the first human tests.
Drug resistance in Plasmodium parasites has long been a major obstacle to developing new treatments for malaria. Researchers believe the unique mode of action of (+)-SJ733, combined the speed with which it kills the parasite, could hold hopes of widespread treatment.
Altering sodium levels in infected blood cells caused changes similar to those seen in aging cells. This triggered immune systems to eliminate the bodies as it would aged blood cells.
"The data suggest that compounds targeting ATP4 induce physical changes in the infected red blood cells that allow the immune system or erythrocyte quality control mechanisms to recognize and rapidly eliminate infected cells. That is important because it leaves uninfected red blood cells, also known as erythrocytes, unharmed," Joseph DeRisi of the Howard Hughes Medical Institute and the University of California stated in a press release.
Development of the new treatment for malaria was detailed in the journal Proceedings of the National Academy of Sciences (PNAS).
