Lack of oxygen doesn’t kill infant brain cell

Posted on September 2, 2019

Research shows that even a brief 30 minute of hypoxia is enough to persistently disrupt the structure and function of the brain region known as the hippocampus, which is important for learning and memory. These findings raise new concerns about the vulnerability of the preterm brain to hypoxia.

Hypoxia concerns the long-term impact that oxygen deprivation can have on the ability of these preterm babies to learn as they grow to school age and adulthood. In the neonatal intensive care unit, preemies can experience up to 600 short, but impactful periods of hypoxia each week. Consequently, more than one-third of babies who survive preterm are likely to have smaller brains, possibly due to brain cell loss, compared to the brains of full-term infants. This can increase the risk of important life-long neurodevelopmental challenges that will affect learning, memory, attention and behaviour.

Using the twin preterm foetal sheep model, Back and his colleagues studied the impact of both hypoxias alone, as well as in combination with ischemia – or insufficient blood flow – one the developing hippocampus. The results confirmed that, like human preterm survivors, growth of the hippocampus is impaired. However, brain cells do not die as previously believed. Rather, hippocampal cells fail to mature as normally, which causes a reduction in long-term potentiation, or the cellular basis of how the brain learns.

Surprisingly, the severity of the hypoxia predicted the degree to which cells in the hippocampus failed to mature normally. These findings were unexpected as it was not appreciated that the preterm hippocampus was already capable of these learning processes.

Researchers seek to understand next how very brief or prolonged exposure to hypoxia affects the ability for optimal learning and memory. This will allow us to understand how the hippocampus responds to a lack of oxygen, creating new mechanisms of care and intervention both at the hospital, and at home.


Category(s):Child Development

Source material from Science Daily