Effects of the active components of Chinese herbal medicine Xiaoxuming Decoction on memory behavior and brain injury in rats with chronic cerebral ischemia
To study the effects of the active components of Xiaoxuming Decoction (XXM), a compound traditional Chinese herbal medicine, on chronic cerebral ischemia in rats. Chronic cerebral ischemia was induced in rats by occlusion of bilateral common carotid arteries. Then, the rats with chronic cerebral ischemia were randomly divided into five groups: model group, extract of Ginkgo biloba group and low-, medium- and high-dose active components of XXM groups. Another 11 rats without occlusion of common carotid arteries were used as the sham-operation group. Memory behavior was investigated by Morris water maze test. The structure of hippocampus and cortex neurons was observed with Nissel staining. The white matter lesion was stained with Klüver-Barrera stain method to observe the pathological changes. The astrocyte activation was observed using immunohistochemical method with glial fibrillary acidic protein (GFAP) antibody. The active components of XXM could significantly improve the impairment of learning and memory induced by chronic cerebral ischemia in rats. Compared with the model group, the time to reach the platform for rats was shortened by treating with the active components of XXM in Morris water maze test, particularly in the medium-dose group (P<0.05). In addition, the low- and medium-dose active components of XXM improved the decrease of cerebrovascular reactivity induced by chronic cerebral ischemia. The results of the pathological analysis also suggested that the active components of XXM could ameliorate the pathological damage induced by chronic cerebral ischemia in rats with the number of neurons increased, and the morphology and distribution of neurons recovered to normal levels. The low-dose active components of XXM significantly reduced the white matter lesions (P<0.05, P<0.01). Active components of XXM treatment could also reduce the activation of astrocytes. The active components of XXM may attenuate the chronic cerebral ischemic injury in rats.