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Objective To observe the effects of ginkgolide B (GB) on mRNA expression of foxgl and proliferation of cells in brain tissue of newborn rats with hypoxic-ischemic brain damage (HIBD).Methods A total of 128 clean 7-day-old healthy SD rats were randomly divided into sham operation group,the model group,the low-GB dose and the high-GB dose treatment groups.Classic Rice method were used to establish HIBD models in the latter 3 groups.Four hours after operation,and GB in dose of 5 mg/kg and 10 mg/kg was given to rats in the low and the high dose treatment groups by intraperitoneal injection postoperatively,once a day for 5 days,while sham operation and model groups were treated with equal physiological saline.All groups were respectively sacrificed on 3 d,7 d,14 d,28 d respectively.Quantitative real-time fluorescent polymerase chain reaction was employed to detect expression of Foxg1 gene.Then the number of 5-bromodeoxyuridine positive cell in subgranular zone was investigated by immunolluorescent stairning.Results The Foxg1 mRNA expression was observed 3 days after HIBD,peaked on 7th day,and then declined gradually; the levels of Foxg1 mRNA in the 2 treatment groups were higher than that of the HIBD group (all P ＜ 0.01) ; The expression of Foxgl at 7 d,14 d,28 d,in high-dose group were higher than those in the low-dose group (all P ＜ 0.01).The number of 5-bromodeoxyuridine positive cell was increased after HIBD,and the levels in the low-and the high-dose treatment groups were all higher than that of the model group (all P ＜ 0.05) ; the number of positive cell in high-dose treatment groups were higher than that in the low-dose treatment groups (P ＜ 0.05).Conclusions GB can promote the expression of Foxg1 gene and improve the proliferation of cells in Brain tissue after HIBD,which shows more significant efficacy in high-dose group than in low-dose group.
RESUMO
Objective To observe the effect on Foxg1 gene expression in the subgranular zone (SGZ) of cerebral tissue from neonatal rats with hypoxic-ischemic brain damage (HIBD) after transplantation of neural stem cells (NSCs) derived from umbilical cord blood.Methods Mononuclear cells separated from umbilical cord blood by density gradient centrifugation were cultured with orientated induction to differentiate the NSCs.The neuronal phenotype was identified using immunocytochemical methods.A total of 150 Sprague-Dawley rats were randomly divided into a sham-operation group,an HIBD group and an HIBD-NSCs group.Rats in the HIBD group and the HIBD-NSCs group were subject to ligation of the left carotid artery and then kept in a box under 8％ oxygen and 92％ nitrogen for 2.5 hours to establish the HIBD animal model.The artery was separated but not ligated in the sham operation group,which was not subjected to hypoxia.Twenty-four hours after the operation,the cultivated NSCs were transplanted by caudal vein injection into the rats in the HIBD-NSCs group.Rats were then sacrificed on the 3rd,7th,14th,21st and 28th days after the operation.Foxg1 gene expression in the SGZ was examined using in-situ hybridization methods.Results The number of Nestin-positive cells peaked on the 6th day of cultivation and then decreased by the 9th day.The Foxg1 gene was expressed in the SGZs of each group.The expression increased by the 3rd day after surgery in the HIBD and HIBD-NSCs groups,and peaked on 7th day after the operation,then declined gradually.The average expression level of Foxg1 in the HIBD group was significantly lower than that in the HIBD-NSCs group on the 7th day and thereafter.Conclusions Human umbilical cord blood mesenchymal stem cells can be induced and differentiated into neural stem cells.Foxg1 genes can still be present in the SGZ after birth.HIBD can induce the expression of Foxg1 genes.Transplanting NSCs can promote the expression of Foxg1 genes and improve morphological and functional recovery after HIBD,at least in neonatal rats.