Hypoxia ischemia, a condition brought about by decreased blood flow and oxygen to the baby's brain, is linked to premature birth and other complications during pregnancy. It causes brain injury in two of every 1,000 full-term human births, and in a high percentage of premature babies born before 34 weeks.
Long-term effects of the condition include seizures, hypoxic ischemic encephalopathy and cerebral palsy.
Pomegranates have a very high polyphenol content - antioxidant compounds also found in blueberries, green tea and red wine in significant quantities. Research has shown that dietary supplementation with polyphenol-rich foods may protect the brain in adult models of ischemia and Alzheimer's disease.
"Hypoxic ischemic brain injury in newborns is very difficult to treat, and right now there's very little we can do to stop or reverse its consequences," said senior author David Holtzman, head of the university's neurology department.
"Most of our efforts focus on stopping it when it happens, but if we could treat everyone who's at risk preventively, we may be able to reduce the impacts of these kinds of injuries."
Holzman hypothesizes that for pregnant women pomegranate may be a useful alternative source of polyphenols to red wine, as alcohol can increase the risk of birth defects.
To test the theory in a mouse model, the researchers gave pregnant female mice water mixed with one of three doses of pomegranate juice during the last third of gestation and throughout the seven days of litter suckling. Control groups were given plain water, sugar water or vitamin C water.
They then temporarily reduced oxygen levels and blood flow in the brains of the pups - a procedure that produces effects similar to those seen in human infants with hypoxia ischemia injuries.
After 24 hours brain injury was assessed biochemically, and after one week histiologically to establish percentage of brain tissue area lost.
In the brains of the mice whose mothers had drunk the pomegranate juice, brain tissue loss was more than 60 percent less in all three areas examined (cortex, hippocampus and striatum), with the best effect seen with the highest dose.
The results of the study, which was conducted in collaboration with POM Wonderful, are published in Pediatric Research (57:858-864 (2005).
Holtzman said that the results indicate that a study involving human mothers-to-be would be useful, but he advised that it would be difficult to assemble a sufficiently large study group due to the relative unpredictability of hypoxia ischemia in newborns.
Nonetheless, he said: "One might advise this group that studies in animals have suggested that drinking pomegranate juice may reduce the risk of injury from hypoxia ischemia."
Ongoing research projects for his team include attempting to isolate the neuroprotective ingredients in pomegranate juice with a view to concentrating them and testing their ability to reduce brain injury. Future plans involve testing the efficacy of pomegranate polyphenols in slowing the progression of other neurological disorders like Alzheimer's disease.