Brain barrier properties and cerebral blood flow in neonatal mice exposed to cerebral hypoxia-ischemia

The study examines how the blood-brain barrier (BBB) and cerebral blood flow (CBF) are affected in newborn mice after a hypoxic-ischemic (HI) event, similar to what happens in human newborns with HIE. The researchers found that the BBB becomes more permeable to molecules shortly after HI, but this effect is temporary. This opening is linked to changes in the proteins that make up the BBB. The location of brain damage was closely related to reduced blood flow during the HI event and to areas where the BBB was compromised, suggesting a strong connection between these factors.

• 1
  Hypoxia-ischemia increased BBB permeability to small and large molecules within hours after the insult, which normalized in the following days.
• 2
  The opening of the BBB was associated with changes to BBB protein expression whereas gene transcript levels were increased showing direct molecular damage to the BBB but also suggesting compensatory mechanisms.
• 3
  Brain pathology was closely related to reductions in rCBF during the hypoxia as well as the areas with compromised BBB showing that these are intimately linked.