Cerebral Protection Of Granulocyte Colony-stimulating Factor Combined With Thrombopoietin On Hypoxic-ischemic Encephalopathy In Neonatal Rats

ObjectiveTo explore the neuroprotective effect of granulocyte colony stimulating factor(G-CSF)combined with thrombopoietin(TPO)on hypoxic-ischemic encephalopathy(HIE)in neonatal rats and its possible mechanism,so as to provide theoretical basis for the clinical application of G-CSF combined with TPO in HIE.Method7-day-old newborn SD rats(n=90)were randomly divided into sham operation group,hypoxia ischemia model group,G-CSF group,TPO group and combined treatment group,with 18 in each group.According to the modified method of Rice model,we builded the hypoxic-ischemic brain injury model in all groups except the sham operation group.The sham operation group only dissected the right common carotid artery without ligation and hypoxia.HIE rats were intraperitoneally injected with the same volume of saline,G-CSF(50ug/kg),TPO(15U/10g)or G-CSF(50ug/kg)combined with TPO(15U/10g)30 minutes after modeling.We measured the weight of 7-day-old and 9-day-old rats to assess their growth situation.At the age of 9 days,the neonatal rats in each group were subjected to acute phase behavioral assessment of righting reflex,negative geotaxis,and front-limb suspension test.TTC staining was used to measure the area of cerebral infarction.Nissl staining was used to evaluate the damage of neurons in the cerebral cortex and hippocampal CAl region.And Western-Blot was used to detect the expression of inflammatory related proteins IL-1β,TNF-α and IL-10 in the brain tissue.ResultWeight growth:Compared with the model group,the weight of the rats in the other treatment groups increased significantly(P<0.05).The weight of the rats in the combined treatment group was increased significantly compared with that in the G-CSF treatment group and TPO treatment group(P<0.05).Results of behavioral evaluation in acute phase:Compared with the model group,the evaluation results of the other treatment groups were significantly improved(P<0.05).Compared with the G-CSF group and the TPO group,the evaluation results of the combination treatment group were significantly improved(P<0.05).TTC staining results:Compared with the sham operation group,the cerebral infarct area of newborn rats in the other groups was significantly increased(P<0.05).Gompared with the model group,the cerebral infarct area of the other treatment groups was significantly reduced(P<0.05).Compared with the G-CSF group and the TPO group,the area of cerebral infarction in the combined treatment group was significantly reduced(P<0.05).Nissl staining results:Compared with the sham operation group,the number of Niss1 staining positive cells in the cortical and hippocampal CA1 area of each group was significantly reduced(P<0.05).Compared with the model group,the Nissl staining positive cells was significantly increased in the other treatment groups(P<0.05).Compared with the G-CSF group and the TPO group,the number of Nissl-positive cells in the combined treatment group was significantly increased(P<0.05).Western-Blot results:1.IL-1β,TNF-α:Compared with the sham operation group,the expression levels of other groups were significantly higher(P<0.05).Compared with model group,the expression level of other treatment groups was significantly lower(P<0.05).Compared with G-CSF group and TPO group,the expression level of combined treatment group was significantly lower(P<0.05).2.IL-10:Compared with the sham operation group,the expression levels of other groups were significantly lower(P<0.05).Compared with the model group,the expression levels of the other treatment groups were significantly higher(P<0.05).Compared with the G-CSF group and TPO group,the expression level of the combined treatment group was significantly higher(P<0.05).ConclusionThe combined application of G-CSF and TPO can reduce the brain damage of neonatal rats caused by HIE by enhancing the anti-apoptotic and anti-inflammatory effects,which is conducive to the weight growth and neural function recovery in the acute phase.