In this study, we investigated the in vivo effects of red wine
polyphenol compounds (RWPC) in rats that were submitted to middle cerebral occlusion as an experimental model of
stroke. Male Wistar rats were given RWPC [30 mg/(kg x d) dissolved in
drinking water] or water for 1 wk before being subjected to transient
middle cerebral artery occlusion followed by reperfusion.
Sham-operated rats were subjected to transient occlusion in which the filament was not completely introduced. The release of
amino acids and energy metabolites were monitored by intracerebral microdialysis. The volume of the ischemic lesion was assessed 24 h after reperfusion. Proteomic analysis of brain tissue was performed to study the effects of
ischemia and RWPC on specific
protein expression. Treatment with RWPC completely prevented the burst of
excitatory amino acids that occurred in response to
ischemia in untreated rats and significantly reduced
brain infarct volumes. Rats chronically treated with RWPC, however, had lower basal concentrations of energy metabolites, including
glucose and
lactate in the brain parenchyma, compared with untreated rats. Chronic RWPC treatment significantly enhanced the residual cerebral blood flow during occlusion and reperfusion in rats subjected to transient occlusion compared with untreated rats. This effect resulted from arterial vasodilatation, as the internal diameters of several arteries were significantly enlarged after RWPC treatment. Proteomic studies revealed the modulation by RWPC of the expression of
proteins involved in the maintenance of neuronal caliber and axon formation, in the protection against oxidative stress, and in energy metabolism. These findings provide an experimental basis for the beneficial effects of RWPC on the neurovascular unit during
stroke.