ABSTRACT
Objective To investigate the neuroprotective effect and mechanism of astragalus injection in cerebral ischemia reperfusion injury in rats .Methods A total of 70 healthy adult male Wistar rats were subjected to establish middle cerebral artery occlusion reperfusion models by inserting a monofilament thread from the external -internal carotid artery and treated by injecting 1g/L intraperitoneally astragalus injection (3ml/kg).The neurobehavioral function of rats was evaluated by Longa ’ s test and the cerebral infarction volume was calculated by tetrazolium chloride staining .The shape and ultrastructure of neurons in parietal cortex were observed by HE stain TEM .The early apoptotic ratio of neurons was detected by flow cytometry .The expressions of c-Jun N-terminal kinase 3 ( JNK3) mRNA and protein were determined by RT-PCR and Western blotting , respectively.Results After treatment with astragalus injection , the expressions of JNK3 mRNA and protein reduced significantly , the number of neuronal apoptosis in parietal cortexminus , the cerebral infarction volume shrink, the neuronal shape and ultrastructure and animal neurobehavioral function were improved significantly than those in model group rats .Conclusion The results suggest that astragalus injection may inhibit neuronal apoptosis , reduce the infarction volume and improve the animal neurobehavioral function by down -regulated the expression of JNK 3 gene following cerebral ischemia in rats .
ABSTRACT
Aim To investigate the effect of astragalus injection on the expression of JNK3(c-jun N terminal kinase)protein and JNK3 mRNA interrelated by apoptosis after hypoxia/hypoglycemia and reoxygenation in hippocampal neurons of rats.Methods The hippocampal neurons cultured for eight days were divided into four groups:normal control group,hypoxia/hypoglycemia and reoxygenation group,astragalus injection group and astragalus solution group.Hypoxia/hypoglycemia and reoxygenation group,astragalus injection group and astragalus solution group were treated with hypoglycemia and reoxygenation after being deprived of oxygen and glucose for 30 minutes.Methods of Western blot,ELISA and RT-PCR were used respectively to measure the expression of JNK3 mRNA after hypoxia/hypoglycemia and reoxygenation 0,0.5,2,6,24,72,120 h.Results Compared with normal control group,the mean optic density(MOD)of expression of JNK3 protein and activation of JNK3 protein in hippocampal neurons of rats every time points increased obviously in hypoxia/hypoglycemia and reoxygenation group except 120 h(P<0.05);compared with hypoxia/ hypoglycemia and reoxygenation group,MOD of expression of JNK3 mRNA and activation of JNK3 protein in hippocampal neurons of rats every time points decreased obviously except 120 h in astragalus injection group (P<0.05);compared with hypoxia/hypoglycemia and reoxygenation group,there was no difference in astragalus solution group.Compared with normal control group,MOD of expression of JNK3 mRNA in hippocampal neurons of rats every time points increased obviously in hypoxia/hypoglycemia and reoxygenation group(P<0.05);compared with hypoxia/ hypoglycemia and reoxygenation group,MOD of expression of JNK3 mRNA in hippocampal neurons of rats every time points decreased obviously in astragalus injection group except 120 h(P<0.05);compared with hypoxia/hypoglycemia and reoxygenation group,there was no difference in astragalus solution group.Conclusion Astragalus injection can inhibit the expression of JNK3 mRNA after hypoxia/hypoglycemia and reoxygenation,moreover,it can inhibit the expression of JNK3 protein and decrease the activation of JNK3 protein,accordingly it inhibits hippocampal neuronal apoptosis.