peoniflorin and Brain-Damage--Chronic

Chronic cerebral hypoperfusion, a mild ischemic condition, is associated with the cognitive deficits of AD. Paeoniflorin (PF), a major constituent of peony root, was proved to be neuroprotective in middle cerebral artery occlusion model. In this study, we investigated whether PF could attenuate chronic cerebral hypoperfusion-induced learning dysfunction and brain damage in rat. Seven weeks after permanent bilateral occlusion of the common carotid arteries, the rats were tested in the Morris water maze. Subsequently, the animals were sacrificed and neurons, astrocytes and microglias were labeled with immunocytochemistry in hippocampus. PF at the dose of 2.5 mg/kg ameliorated cerebral hypoperfusion-related learning dysfunction and prevented CA1 neuron damage. Chronic cerebral hypoperfusion increased the immunoreactivity of astrocytes and microglias in hippocampus. The increase was prevented by PF at the dose of 2.5 mg/kg. Cerebral hypoperfusion also increased expression of nuclear factor-kappaB (NF-kappaB), mostly in astrocytes, but not in neurons. With the treatment of PF (2.5 mg/kg), NF-kappaB immunostaining was diminished in hippocampus. Our results demonstrated that PF could attenuate cognitive deficit and brain damage induced by chronic cerebral hypoperfusion and that suppression of neuroinflammatory reaction in brain might be involved in PF-induced neuroprotection.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoates; Biomarkers; Brain Damage, Chronic; Brain Ischemia; Bridged-Ring Compounds; Cerebral Infarction; Disease Models, Animal; Dose-Response Relationship, Drug; Encephalitis; Gliosis; Glucosides; Hippocampus; Infarction, Middle Cerebral Artery; Learning Disabilities; Male; Maze Learning; Memory Disorders; Monoterpenes; Nerve Degeneration; Neuroglia; Neurons; Neuroprotective Agents; NF-kappa B; Rats; Treatment Outcome