Hope for premature babies with neurologic disabilities
medwireNews: Damage caused by cerebral ischemia in premature babies could be reversed or prevented with early intervention, suggests research carried out in sheep and published in Science Translational Medicine.
A second study published in the same journal showed that impaired growth of premature babies was the strongest predictor of magnetic resonance imaging (MRI) abnormalities, and the investigators suggest that improved nutrition and growth of these infants could potentially lead to improved cortical development.
"As neurologists, we thought ischemia killed the neurons and that they were irreversibly lost from the brain. But this new data challenges that notion by showing that ischemia, or low blood flow to the brain, can alter the maturation of the neurons without causing the death of these cells," said Stephen Back (Oregon Health & Science University, Portland, USA), senior author of the sheep study, in a press statement.
"As a result, we can focus greater attention on developing the right interventions, at the right time early in development, to promote neurons to more fully mature and reduce the often serious impact of preterm birth. We now have a much more hopeful scenario," he added.
Back and team analyzed the brain structures of fetal lambs that experienced cerebral ischemia at about two-thirds of the full gestation period. The researchers then carried out MRI and histological analysis 1, 2, and 4 weeks after the initial ischemic event. Similar investigations were carried out in age-matched lambs that were not exposed to ischemia for comparison purposes.
They found no evidence of destruction or loss of brain cells in the cerebral cortex in the animals exposed to ischemia. However, they did observe that synaptic density was lower and that brain cells in this area appeared to be immature and undeveloped compared with those of similarly aged lambs that were not exposed to ischemia.
In the other study, Steven Miller (University of Toronto, Ontario, Canada) and colleagues scanned 95 babies born at 24-32 weeks of gestation 2 months before their due date and at full-term age using MRI. Factors associated with MRI abnormalities at both scans were analyzed.
They found that after accounting for the presence of infections or illness, as well as different growth parameters, the development of normal brain structure significantly correlated with postnatal growth.
"I believe these studies provide hope for the future for preterm babies with brain injury, because our findings suggest that neurons are not being permanently lost from the human cerebral cortex due to ischemia. This raises the possibility that neurodevelopmental enrichment - or perhaps improved early infant nutrition - as suggested by the companion paper, might make a difference in terms of improved cognitive outcome," commented Back.
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Helen Albert, Senior medwireNews Reporter