The Anti-injury Effect Of Breviscapine Injection On The Hypoxic Ischemic Brain Damage Of Neonatal Rats And The Expression Of Bcl-2 And Bax

Objective: Since the 90's, the effective treatment method is always the focus of the study in neonatal hypoxic-ischemic brain damage(HIBD), but did not achieve a breakthrough. In recent years, more and more attention was paid to the Traditional Chinese Medicine (TCM) for the therapy of HIBD. The active ingredients can target at many aspects of brain injury after hypoxia-ischemia. With the effect of anti-oxidation, scavenging free radicals, and broadenning capillary, at present, Breviscapine injection(BI) mainly used in clinical for treatment of cerebral infarction caused by cerebral ischemia. While the application of breviscapine injection to the therapy of HIBD has not been reported. In this experiment 7-day-old newborn rat of hypoxic-ischemic brain damage modle was used . Immuno- histochemical staining was used to assay the expresssion of Bcl-2 and Bax protein in the CA1 hippocampus of different time points after HIBD and the Bcl-2, Bax protein changes after BI treatment in neonatal rats after HIBD. To provide evidence for clinical therapy of neonatal HIBD.Methods: seventy two 7-day-old SD rats were randomly divided into three groups: sham group (n = 24): in the Operation of neck, the rats were only exposed the left common carotid artery but not ligated. Not to hypoxia.HIBD group(n=24): 7-day old SD rats were operated by ligating their left common carotid artery and exposing them to 8% oxygen for two hours.BI+HIBD group(n=24): 7-day-old SD rats were operated by ligating their left common carotid artery and exposing them to 8% oxygen for two hours. after this, intraperitoneal injection according to the weight with BI once a day began immediately after HIBD.The animals were sacrified by decapitation on 24 h, 3 d, 7 d, 14 d. rats were used to study histological change and the protein expression for Bcl-2 and Bax by thionin staining and immunohistochemistry.Results:1 The expression of Bcl-2 protein: Immunohisto-che- mical staining showed that it has no obvious positive cells in the CA1 hippocampus in sham group. Compared with the sham gro- up, HIBD group ,The level of Bcl-2 expression gradually increa- sed (P <0.05) within 24 h (P<0.05 ), peaked at 3 d after HIBD(P <0.05 vs other groups) and decreased after this. In BI+HIBD gr- oup the expression of Bcl-2 protein was increased compared wi- th HIBD group (P<0.05), peaked at 3 d and decreased in 7 d, 14 d(P< 0.05 vs HIBD). 7 d group and model group, the correspon- ding time point of comparison, the differences are still singnific- ant (P<0.05).2 The expression of Bax protein: It has no obviously positive cells in the CA1 hippocampus in sham group. The expression of Bax protein in the HIBD group began to increase within 24 h (P<0.05 vs sham), peaked at 3 d after HIBD (P<0.05 vs other groups) and decreased after this. In therapy group the expression of Bax protein was decreased compared with HIBD group (P<0.05) at each time, it has a minimum expression at 3 d and increased in 7 d, 14d(P<0.05 vs HIBD).3 Thionin staining result :It was found by thionin staining that there was no significant neuronal damage in the CA1 hippocam- pus in the sham groups.The alinement and shape of hippocamp- us neurons begin to be disordered at 24h after HIBD, the degen- erated and necrotic neurons increased progressively at 7d after HIBD. Obvious destruction of the CA1 hippocampus was found in HIBD group, the value of ND was decreased, and HG was in- creased compared with that in the sham group (P<0.05).At 14 d following HIBD, the existent neurons decreased in number.The therapy group showed a significant protective effect against the DND induced by HIBD, which was represented with the increa- se in ND value and decrease in HG in therapy group compared with HIBD group(P<0.05).Conclusion:The expression of Bcl-2 and Bax protein was both increeased after HIBD in the CA1 hippocampus, HIBD treated rats given Bcl-2 protein, Bax protein expression were increased in hippocampal CA1 neurons in the loss of a large number of necrosis,The degenerated and necrotic neurons increased, HG significantly increased. Breviscapine treatment, Bcl-2 protein was further increased while Bax protein decreased, the neurons destruction of the CA1 hippocampus were obvious lightened. According to this date,There are neuronal apoptosis and change of Bcl-2,Bax protein expression.Breviscapin Injection could reduce the apoptosis of neuron after severe brain injury through improving the expression of Bcl-2 protein and inhibiting expression of Bax.The study will to be provide a fine theoretical foundation for clinical therapy of neonatal HIBD.