RESUMO
Global cerebral ischemia/reperfusion (I/R) induces selective neuronal injury in the hippocampus, leading to severe impairment in behavior, learning, and memory functions. This study aimed to evaluate the neuroprotective effects of bisoprolol (biso) and vitamin E (vit E) treatment alone or in combination on cerebral ischemia/reperfusion (I/R) injury. A total of 30 male rats were divided randomly into five groups (n = 6), sham, I/R, I/R + biso, I/R + vit E, and I/R + biso+vit E. Cerebral I/R group underwent global ischemia by bilateral common carotid artery occlusion for 20 min. Treatment groups received drugs once daily intraperitoneally for 7 days before the I/R induction. Locomotive and cognitive behaviors were utilized by open-field and Morris water maze tests. After behavioral testing, the brain was removed and processed to evaluate cerebral infarct size, histopathologic changes, myeloperoxidase (MPO) activity, and malondialdehyde (MDA) level. In I/R group tissue MDA and MPO levels and cerebral infarct size were significantly increased in comparison with the sham group. Furthermore, significant deficits were observed in locomotion and spatial memory after I/R. The areas of cerebral infarction, MPO, and MDA levels in biso, vit E, and combination group were significantly reduced compared with I/R group. Histopathological analysis demonstrated a significant reduction in leukocyte infiltration in all treated groups with the most profound reduction in the combination group. According to the behavioral tests, administration of biso and/or vit E protected locomotive ability and improved spatial memory after cerebral I/R. Our findings show that biso and vit E have beneficial effects against the I/R injury and due to their synergistic effects when administered in combination, may have a more pronounced protective effect on the cerebral I/R injury.
