Mechanism of Baicalin on High Altitude Cerebral Hypoxia-ischemia on Mice / 世界科学技术-中医药现代化

ABSTRACT

This study was aimed to explore the mechanism of baicalin on high altitude cerebral hypoxia-ischemia on mice and its influence on related target protein expressions. Morris water maze was used to screen 50 Kunming mice, which were randomly divided into the model group, control group, the low dose (0.05 mg·kg-1), middle dose (0.20 mg·kg-1) and high dose (0.60 mg·kg-1) baicalin group, with 10 rats in each group. The space memory and learning ability of mice were tested. The animal cabin with low oxygen (simulating at 4 000 m altitude) was used to establish the stable high altitude cerebral hypoxia-ischemia mouse model. Changes on SOD content, GSH-PX activities and MDA content in hippocampal tissues of mice were detected. The expressions of different target proteins, including cleaved-caspase 3, P-AKT, GFAP, Bax and Bcl-2 in brain stem of mice were detected by western blot. The results showed that the latent period of the model group was obviously longer than that of the control group (P < 0.05). The latent period of high dose baicalin group was shorter than the model group with significant difference (P< 0.05). Therefore, the best effective dose of baicalin was 0.60 mg·kg-1. Compared with the control group, the content of MDA in the hippocampal tissues of mice in the model group was significantly increased; the SOD and GSH-PX activity were obviously reduced (P < 0.05). Compared with the model group, the SOD and GSH-PX activity were obviously increased in the brain tissues of mice in the high dose baicalin group; and the content of MDA was obviously reduced (P < 0.05). From the level of protein changes, the stripes of cleaved-caspase 3, P-AKT, GFAP protein expressions in the model group were strengthened compared to the control group; the ratio of Bax/Bcl-2 was also obviously increased (P < 0.05). The expression of the baicalin group was lower than that of the model group (P < 0.05). Among them, the expression of the high dose baicalin group was the lowest. It had certain dose-response relationship. It was concluded that baicalin had protective effect on high altitude cerebral hypoxia-ischemia. Its mechanism may be related to its powerful oxidation resistance and its inhibition on expression of different target proteins, including cleaved-caspase 3, P-AKT, GFAP, Bax, Bcl-2 for the change of apoptotic pathway.