The Protective Effect Of RasGRP1 In Oxygen Glucose Deprivation And Reperfusion By Activated ERK Signaling Pathway

Objective:To study the N2 a cell apoptosis after reperfusion and the changes of the expression of RasGRP1 protein and explore the effect of oxygen glucose deprivation,ERK signaling pathway RasGRP1 on N2 a cell oxygen glucose deprivation and reperfusion after the treatment.The aim is that investigating the role of RasGRP1 in oxygen glucose deprivation and reperfusion injury and its possible mechanism.Methods:mouse neuroblastoma N2 a cells were selected as the research object,and randomly divided into 5 groups,which were treated with oxygen glucose deprivation,and oxygen glucose deprivation for 4 hours.The cells were observed under the optical microscope and photographed by flow cytometry.The changes of cell apoptosis,expression of RasGRP1 mRNA was detected by Real-time PCR,the expression of RasGRP1 protein was detected by Western blot.Si RNA was used to silence the expression of RasGRP1,the apoptosis rate of each group was detected by flow cytometry,and in the case of oxygen glucose deprivation for 4hours and reperfusion for 12 hours,the expression of ERK1/2 and p-ERK1/2 protein in each group was detected by Western blot.Results:1.The changes of apoptosis rate of oxygen glucose deprivation and reperfusion: The cell apoptosis rate was increased after the time ofoxygen glucose deprivation prolonged.The apoptosis rate of OGD group was obviously higher than that of normal control group(P<0.05).OGD/R4 h group apoptosis rate was obviously higher than normal control group(P<0.05),with the prolongation of reperfusion,the apoptosis and reperfusion 12 hour group and 24 hour group cells was significantly increased,compared to the control group,the difference was significantly(P<0.01).2.The expression change of RasGRP1 mRNA: The expression of RasGRP1 mRNA was gradually increased with the prolongation of oxygen glucose deprivation reperfusion time.There was no significant difference in the RasGRP1 mRNA between OGD group compared with the control group(P>0.05).The expression of RasGRP1 mRNA in OGD/R4 h group slightly increased compared with the control group(P<0.05).The OGD/R12 h and OGD/R24 h group of RasGRP1 mRNA was increased significantly comparing with the control group(P<0.01).3.The expression of RasGRP1 was significantly lower than that of the blank control group and the normal group after 4 hours of oxygen glucose deprivation and reperfusion for about 12 hours or 24 hours shows that the apoptosis rate was significantly higher(P<0.05).4.The expression of ERK2 and p-ERK1/2 in the RasGRP1 expression lower group was significantly lower than the in the blank group or the normal group(P<0.05).Conclusion:1.After the oxygen glucose deprivation reperfusion,the apoptosis rate of N2 a cells was increased.Also the expression of RasGRP1 was increased with the change of oxygen glucose deprivation reperfusion time.2.RasGRP1 can inhibit the apoptosis of neurons after oxygen glucose deprivation,which may be related to the activation of ERKsignaling pathway.