MiR-134 Expression Dynamic Change Trend In Hippocampus Tissue And Peripheral Blood After The Seizure

Objective:1.To investigate the dynamic changes of miR-134 expression at different time points after epileptic seizures.2.To investigate if there is consistency in the dynamic expression of miR-134 in the brain and peripheral blood of epileptic rats.3.Whether miR-134 expression in peripheral blood can be used as a biomarker for further study.Methods:The experimental adult wistar female rats were used to establish rat epilepsy model by intraperitoneal injection of pentylenetetrazol 62 mg/kg.Rats in the control group were prepared by intraperitoneal injection of saline,and epileptic status was achieved according to the Racine classification.According to the principle of experimental control and different time points after epileptic seizures were divided into 11 experimental groups(control group,0.5h group,1h group,6h group,12 h group,24 h group,48 h group,72 h group,1w group,2w group,4w Groups)Six randomized surviving mice were randomly assigned to experimental analysis in each experimental group.Blood samples were collected from the peripheral blood of rats in each group for cryopreservation using the ophthalmic artery blood sampling method.Immediately after dislocation of the spine,the hippocampus was frozen and stored.The real-time fluorescence quantitative PCR was used to detect the microRNA-134(miR-134)in hippocampus tissues and blood.expression.SPSS 22.0 software was used to statistically analyze the data obtained in each group,using independent sample t-test,independent sample Mann-Whitney U test,Pearson correlation coefficient analysis,Spearman correlation coefficient analysis,and linear regression significant level test.P<0.05 was considered statistically significant.Results:1.Expression of miR-134 in hippocampus and peripheral blood increased gradually with time in several hours after seizure,reaching the peak at 72 hours;then the amount of miR-134 decreased gradually and was lower than that in control group.2.The expression of miR-134 in hippocampal tissue and peripheral blood increased significantly during epileptic seizures,and there was a significant difference compared with the control group(P=0.037 in hippocampus;P=0.042 in peripheral blood).The expression of miR-134 in hippocampus and peripheral blood was significantly lower in the interictal group than in the control group(P=0.002 in hippocampus;P=0.000 in peripheral blood).The expression of miR-134 in the hippocampus was significantly higher than that in the interictal period(P=0.001).The expression of mi R-134 in the peripheral blood was significantly higher than that in the interictal group(P=0.001).The expression of miR-134 in peripheral blood was significantly higher at each time point in the attack phase than in the control group(P<0.05);the expression level of miR-134 in peripheral blood was significantly lower in the peripheral blood during the attack period than in the control group(P <0.05).3.The expression of miR-134 in hippocampus and peripheral blood has a consistent trend after seizures.At 6h,12 h,24h,48 h,72h,1w,2w,and 4w after seizure,the expression of miR-134 in the hippocampus and surrounding blood was correlated(P<0.05),and the 72-hour group had the strongest correlation(P=0.000,r = 0.986).At the above time points,the expression level of miR-134 in peripheral blood can reflect the level of miR-134 expression in hippocampus.Conclusion:1.The expression of miR-134 increased gradually after epileptic seizures,peaked at 72 h,and gradually decreased from normal level during the interictal period;2.Dynamic expression of mi R-134 in hippocampus and peripheral blood has a consistent trend.3.The expression of miR-134 in hippocampal tissues and peripheral blood was correlated,and the correlation was the strongest at 72 h after epilepsy,suggesting that miR-134 in peripheral blood can be further studied as a biomarker for epileptic discharge.