Scutellaria flavonoid supplementation reverses ageing-related cognitive impairment and neuronal changes in aged rats

Primary objective: To study the effects of flavonoid, isolated from aerial parts of Scutellaria baicalensis Georgi (SSF), on memory impairment, neuronal damage, free radicals and energy metabolite disorders in aged rats. Methods and procedures: Approximately 25-month-old rats were used to establish the ageing model. The cognition of the rats was determined using the Morris water maze, neuronal morphology was observed by light/electron microscope, malondialdehyde (MDA) levels and the activity of superoxide dismutase (SOD), lactate dehydrogenase (LDH) and Na+-K+-ATPase were measured by spectrophotometry. Main outcomes and results: In the Morris water maze task, the aged rats always took longer latency to find the hidden platform and spent less time swimming in the target quadrant than those of young control rats. The light/electron microscopic observations found significant neuropathological changes in the aged rats' brain. In addition, the production of MDA and the activity of SOD, LDH and Na+-K+-ATPase in the hippocampus and cerebral cortex of the aged rats showed critical abnormal changes. However, pre-treatment of the aged rats with SSF (35-140 mg kg-1) for 16-21 days dramatically improved cognitive dysfunction, neuropathological changes and biochemical abnormalities. Conclusion: These results indicate that the beneficial effects of SSF on memory impairment and neuronal damage in aged rats may be important for the treatment of senile dementia and for delaying the ageing processes.