Molecular Mechanism Of Long-term Neuroprotective Effects Of Gradual Flow Restoration On Cerebral Ischemia Reperfusion Injurs In MCAO Rats

Background and purpose of studyCerebral ischemia-reperfusion injury is deleterious to patients with acute occlusion of major intracranial artery receiving endovascular thrombectomy.Previous studies revealed that Gradual Flow Restoration(GFR)could effectively reduce brain injury in the short term,but its long-term protective effect,details and mechanisms of neuroprotection process are still unclear.Therefore,prolonging the postoperative detection time of model rats and finding a number of related transcription factors involved in the ischemia-reperfusion injuries process will provide molecular clues for the long-term neuroprotection of GFR intervention,and thus provide potential therapeutic targets for the treatment of CIRI.MethodsThe middle cerebral artery occlusion(MCAO)model was established by thread occlusion in rats,and the rats were randomly divided into GFR group,RFR group,and PO group,the sham group was control group.According to the different times after reperfusion,the four groups were further divided into three subgroups:1,3 and 7 days.The neurological deficit behavior score and 2,3,5-triphenyl tetrazolium chloride(TTC)staining performed to evaluate the degree of brain damage in GFR and other interventions at different time.The key differentially expressed genes related to cerebral ischemia reperfusion injury were initially screened and identified by GSE32529 microarray analysis using GEO database.and the expression screening protein by Gene Chip protein on cerebral cortex infarction in MCAO rats was detected by Western blotting.ResultsMCAO rats intervened with GFR exhibited reduced neurological deficit,and alleviated brain infarction volume.Compared to Sham group,the neurological function of MCAO rats was significantly impaired and cerebral infarction volume was significantly increased(P<0.001).The neurological deficit and cerebral infarction volume in GFR group were significantly lower than those in RFR group and PO group(P<0.001),but RFR group and PO group were no difference in neurological deficit(P>0.05),while the volume of cerebral infarction was statistically significant(P<0.05).The results of microarray screening showed that Repressor element-1 silencing transcription factor(REST)was highly expressed in the brain tissue of rats after ischemia-reperfusion,and the downstream regulatory genes expression of REST were down-regulated such as such as BRINP1,CALB1,GABRD,L1CAM and et al at the same time.Western blot results showed that the expression of REST protein in MCAO groups were significantly higher than that in Sham group(P<0.05),while comparing with PO group,the level of REST expression in RFR group and GFR group was significantly lower(P<0.01).Compared with RFR group,the expression of REST protein in GFR group was inhibited(P<0.01).The GFR intervention inhibited REST expression,and alleviated brain injury on MCAO rats.All the indexes were improved with the prolongation of reperfusion time.ConclusionGFR intervention plays a long-term neuroprotective role.And the expression level of REST was increased in cerebral ischemia-reperfusion injury.GFR could reduce brain injury and neurological deficit through down-regulating REST expression,and play a neuroprotective role.