Studying pregnant mice, researchers at Washington University School of Medicine in St. Louis found that Zika virus manipulates the body's normal barrier to infection, and that hydroxychloroquine, a malaria drug related to chloroquine, interferes with this process, protecting the fetus from viral infection. Photo by Bin Cao
July 10 (UPI) -- Researchers at Washington University School of Medicine found that a drug used to treat malaria may protect fetuses from the Zika virus.
In mice studies, researchers discovered the Zika virus infects the fetus by manipulating the body's normal barrier to infection.
"We found that the malaria drug hydroxychloroquine effectively blocks viral transmission to the fetus," Indira Mysorekar, an associate professor of obstetrics and gynecology, and of pathology and immunology, said in a press release. "This drug already is used in pregnant women to treat malaria, and we suggest that it warrants evaluation in primates and women to diminish the risks of Zika infection and disease in developing fetuses."
The study, published July 10 in The Journal of Experimental Medicine, initially involved infecting human placental cells with the Zika virus.
Researchers found that exposure to Zika activated genes related to autophagy and that when they treated the cells with drugs to increase the autophagy pathway, the number of cells infected with Zika increased and drugs that suppressed autophagy decreased the amount of placental cells infected with Zika.
They then infected two groups of pregnant mice with Zika with one group having the autography process disrupted and the other working normally.
Mice with a weak autophagy response had 10 times fewer viruses in the placenta and heads of the fetuses and less placental damage.
"It appears that Zika virus takes advantage of the autophagy process in the placenta to promote its survival and infection of placental cells," Bin Cao, a postdoctoral fellow, said.
Hydroxychloroquine suppresses this autography response and mice treated with the drug had significantly less Zika virus in the fetuses and placentas.