Protective Effect Of Extract Of Astragalus Against Focal Cerebral Ischemia-reperfusion Injury

Extract of astragalus(EA) is the compound of effective parts mainly composed of astragalosides and astragalus polysaccharides,which was extracted from the root of a traditional Chinese medicine-astragalus. In this paper, the protective effect of EA on focal cerebral ischemia-reperfusion injury and its mechanism were studied.1. EA80mg/kg could decrease the neurological function score after MCAO 2h reperfusion 2h. EA40,80mg/kg could decrease the neurological function score after MCAO2h reperfusion 12h and EA20,40,80mg/kg could significantly decrease the neurological function score after MCAO2h reperfusion 24h in rats.2. EA20,40,80mg/kg decreased the water content and infarction volume of brain in rats after focal cerebral ischemia-reperfusion and improvement in histopathologic examination be observed compared with model group.3. EA20,40,80mg/kg might significantly inhibit the increase of MDA,LD after cerebral ischemia-reperfusion.EA40,80mg/kg also inhibited the decrease of activity of SOD in rats.4. EA20,40,80mg/kg significantly protected the mitochondrion of the brain in rats after MCAO. EA20,40,80mg/kg inhibited the increase of MDA and inhibited the decrease of activities of SOD, Na+-K+ATPase,Ca2+-Mg2+ATPase in mitochondrion .5.EA20,40,80mg/kg could significantly inhibited the express of the TNF- a and inhibited the increase of the IL-1 after MCAO 2h reperfusion 24h in rats.6. EA could significantly inhibited the apoptosis of the neurons after focal cerebral ischemia-reperfusion.The examination with transmission electron microscopy methodshowed that EA20,40mg,kg could protected the ultrastructure Destruction after FCIR. Apoptosis cell could signed with TUNEL method, results showed that EA 20, 40, 80 mg,kg decreased the percentage of the apoptosis cell in brain section.7. EA80mg,kg could inhibit the increase of the blood viscosity, high shear rate reduced viscosity, high shear relative reduced viscosity and low shear relative reduced viscosity after MCAO 2h reperfusion 24h in rats.8. EA40,80,160,320mg,ml had significantly thrombolysis effect in vitro, the serums of the EA 20,40,80mg,kg group had significantly thrombolysis effect in vitro.Conclusion: EA had protective effects against cerebral ischemia reperfusion injuriesvia attenuating cerebral OFR lipid peroxidation , inhibiting inflammatory reaction, protecting mitochondria , inhibiting apoptosis of the neuron and thrombolysis effects.