Oxidative stress is an important element in the etiology of ischemic stroke.
Lowbush blueberries (Vaccinium angustifolium Aiton) have a high antioxidant
capacity and thus we determined whether consumption of lowbush blueberries would
protect neurons from stroke-induced damage. Rats were fed AIN-93G diets
containing 0 or 14.3% blueberries (g fresh weight/100 g feed) for 6 weeks.
Stroke was then simulated by ligation of the left common carotid artery
(ischemia), followed by hypoxia. One week later, plasma and urine were
collected, and neuronal damage in the hippocampus was determined histologically.
In control rats, hypoxia-ischemia resulted in 40 +/- 2% loss of neurons in the
hippocampus of the left cerebral hemisphere, as compared to the right
hemisphere. Rats on blueberry-supplemented diets lost only 17 +/- 2% of neurons
in the ischemic hippocampus. Neuroprotection was observed in the CA1 and CA2
regions, but not CA3 region, of the hippocampus. The blueberry diet had no
detectable effects on the plasma or urine oxygen radical absorbance capacity
(ORAC) or plasma lipids. We conclude that consumption of lowbush blueberries by
rats confers protection to the brain against damage from ischemia, suggesting
that inclusion of blueberries in the diet may improve ischemic stroke outcomes.