September 26, 2017
Can Birth Defects from Zika Be Prevented?

Can Birth Defects from Zika Be Prevented?

by Berkeley Wellness  |  

There’s agreement in the scientific community that the outbreak of Zika virus in Brazil is responsible for that country’s dramatic increase in cases of microcephaly—a birth defect in which a child is born with an abnormally small head, often accompanied by brain damage. But so far the reason why Zika would cause microcephaly has been elusive. A research letter published recently in Lancet: Infectious Diseases by Edward Blonz, PhD, a faculty member in clinical pharmacy at the University of California, San Francisco, and member of our editorial board, proposes a possible explanation.

Blonz theorizes that the Zika virus may inhibit GLUT1, a protein that is responsible for transporting glucose (energy) across the placenta to the fetus, and across the blood-brain barrier to the developing fetal brain. This would result in an insufficient supply of the glucose which is critical for normal placental development, fetal growth, and most critically, normal fetal brain development. Microcephaly is a recognized problem in children born with a genetic GLUT1 defect.

While research has yet to examine whether Zika affects GLUT1, a 2016 study found that the dengue virus, which is also spread by mosquitoes, appears to inhibit the key enzyme, called protein kinase C, that is associated with GLUT1 functionality. Dengue and Zika are in the same genus of viruses, called Flavavirus.

If the connection is confirmed, one option for pregnant women might be to increase their consumption of energy sources that don’t depend on GLUT1 to cross the placenta, reach the fetus and fuel the development of the fetal brain. Of particular promise, according to Blonz: a fatty acid called caprylic acid, a minor fat found in the medium-chain triglycerides of the coconut. Earlier outbreaks of Zika in Micronesia and French Polynesia, where consumption of coconut oil is common, have reported a fraction of the incidence of microcephaly as has been reported in Brazil.

The amount of caprylic acid that would be needed to reduce a woman’s risk of delivering a baby with microcephaly isn’t known at present. But since it’s a normal part of the diet for pregnant women in the Pacific areas, the risks to pregnant Brazilian women of increasing their intake of non-GLUT1 dependent sources of energy, such as the caprylic acid in coconut, is likely to be minor, Blonz says. But, he qualifies, it is always best to consult with your physician to address any concerns.

Bottom line: “The Zika virus, through an effect on GLUT1, may be inhibiting access to the energy needed to build the fetal brain,” Blonz says. “There are energy resources that do not rely on GLUT1, and the provision of these may give the placenta and fetus the energy it needs for normal development.” With the impending spread of the Zika epidemic and its impact on South America—and with the 2016 summer Olympics in Brazil around the corner—“timing is of the essence” in exploring whether dietary interventions modeled after the Micronesian and French Polynesian experiences could help to blunt Zika’s effects in the rest of the world.

Also see Zika Virus: Answers to Your Questions and Zika Virus and Travel.