The Study Of The Effects Of Astragalus Mongholicus On The Anoxic-ischemia And Glutamate Induced Neurotoxicity

Modern pharmacological study have indicated that astragalus mongholicus is rich in astragalus mongholicus saponin, astragalus polysaccharides, flavanoid, selenium, as well as 21 kinds of amino acids and participated in multiple metabolism activity. Astragalus mongholicus has been clinically used for enriching immunity, diuresis, anti-aging, liver protection, depressurization, promoting heart function, coronary vessels and peripheral blood expansion, and anti-virus and bacterium. In addition, astragalus mongholicus had been testified having therapy effect on coryza, chronic nephritis and stroke.Many patients suffering stroke, have the symptom of flabbiness and adynamia of one side limb, fatigue liability, bad appetite, tasteless, hidrosis etc. From the traditional Chinese medicine point, all of these symptoms are resulted from deficiency in origin. The traditional Chinese physician often selects astragalus mongholicus to deal with this state. But the therapy mechanism of astragalus mongholicus on cerebrovascular disease is obscure. The study of the effects of astragalus mongholicus on the neurons and its effects to anoxyaemia and glutamate induced neurotoxicity have important significance. And the study of the function of astragalus mongholicus will offer useful data and theory proof for the therapy of cerebrovascular disease with this Chinese Herb.Objective: To explore the effects of astragalus mongholicus on the cultured hippocampal neuron in vitro and identify the protective mechanism of astragalus mongholicus on anoxic-ischemic injury and glutamate induced neurotoxicity. Methods:The dose-effect curve was illustrated by adding different concentration of astragalus mongholicus into the culture medium of hippocampal neurons. The livability was measured by MTT test. By using DMEM culture medium without glucose, abolishing serum from the culture medium and replacing O2 with N2, the anoxic-ischemic hippocampal neuron model was established. The injury of anoxic-ischemic injury the hippocampal neurons and the protective effect of astragalus mongholicus was evaluated by MTT test, LDH detection and BDNF, NGF and NT-3 immunohistochemical staining. By adding glutamate into the culture medium, we observed the neurotoxicity on the hippocampal neurons. The apoptosis promoting protein Bax was detected by immunocytochemistry. The protective effect of astragalus mongholicus on the glutamate-induced neurotoxicity was valuated. Results:Appropriate astragalus mongholicus could increase the livability of cultured hippocampal neurons in vitro. The best selective concentration was 300 g/L. Anoxic-ischemic injury could cause lipid peroxidation damage on hippocampal neuron with an obvious increase of LDH leakage. The anoxic-ischemic injury induced death of many hippocampal neurons accompanying with an obvious down-regulation of BDNF. Astragalus mongholicus presented a protective effect on neurons suffered by anoxic-ischemic injury through decreasing the LDH leakage and up-regulating the expression of BDNF. Glutamate neurotoxicity induced an increase of Bax expression and astragalus mongholicus could down-regulate Bax and protect hippocampal neurons. Conclusion:Appropriate astragalus mongholicus could increase the livability of cultured hippocampal neurons and protect neurons from anoxic-ischemic injury and glutamate induced neurotoxicity by regulating BDNF and Bax expression.