The Effect Of RhG-CSF On Neuroprotection And Plasticity After Acute Cerebral Ischemia In Rat

Background:Ischemic acute cerebral infarction is a common disease of nervous system.The severe disabilitity is becoming a serious medical problem.How to reduce the fatality,promote the recovery of nerve function and improve the life quality are becoming currently essential mission.Objective:In this study,we used fishing line to subject a model of acute ischemic stroke in rat.For the purpose of providing evidence on rhG-CSF treatment in ischemic stroke,we utilized HE staining.Immuno-histochemistry,Molecular Biotechnology to observe the rhG-CSF on the model of cerebral protection and remodeling.Methods:A total of 108 male Wistar rats,whose weight fluctuations in 270-290g,were randomly assigned to the ischemia group,drug group and the sham operated group.Furthermore,every groups were divided into 1 day,4day,7day and 10 day after infarction.Following Koizumi's method,we subjected middle cerebral artery occlusion(MCAO) by processed fishing line.Drug group were injected rhG-CSF while sham operated group and ischemia group were injected saline.The animals evaluated by neurological deficit score and we identify the changes in pathology with HE staining and infarct volume with TTC,to evaluate the protective effect of rhG-CSF and how to reduce the brain histopathological damage;Immunohistological staining was used to detect S-100βand VEGF expression in brain.Moreover,reverse transaction-polymrase chain reaction(RT-PCR) was used to verify GAP-43 expression,then we can explore the rhG-CSF effect on the nerves,blood vessels and how to reduce the impact of biochemical damage.Results:1,Histopathological:In ischemia group it was discovered that nerve cell nucleus disaggregation,cytoplasm edema,gliocyte hyperplasia;while in drug group neurocyte and gliocyte hyperplasia were specifically found.There has lots of neural precursor cells moving toward the ischemic area after one day.At 4d after injury it showed lymphocytes surrounding vascellums but grew downwards at 10d.Further more,the density of blood vessels began to increase at 7d after injury.2,The neurological deficit symptoms appeared more significantly in ischemia group than in drug group(P＜0.05),and the sham operated group cannot be found deficit symptoms.3,The expression of S-100βdid not increase significantly in the sham operated group.In drug group and ischemia group it appeared obvious up-regulation and was lower in drug group than ischemia group at every time point(P＜0.05).4,During the 1d-10d,GAP-43 expression showed an aggravated trend in ischemia group and drug group.The expression between them were different at every time point(P＜0.01).5,The expression of VEGF increased slowly in 1d-10d ischemia group. Furthermore,it also up-regulated in drug group,it appeared obvious up-regulation in 1d-4d and the peak achieved at 4d after injury.Then it presented a down regulation trend in 4d-10d.Compared with the sham operated group,it still have a predominant distinction at 10d.Conclusions:1,rhG-CSF reduce the infarction volume and relieve the impairment of nervous tissue;2,rhG-CSF reduced its expression,and indirectly played a role of cerebral protection.3,rhG-CSF enhance and extend GAP-43 mRNA expression to promote axons regeneration,which make for the central nervous system repairing after injury.Besides this it can increase VEGF protein and forward its peak so that causing microvascular formation surrounding infarction zone.The above-mentioned directly promote axon regeneration and revascularization in molecular level.