Protective Role Of Salidroside Against High Glucose-induced Apoptosis Via NF-κB Pathway In Primary HT22 Hippocampal Neurons

To explore the effect of salidroside(SAL)on the apoptosis of HT22 hippocampal neurons by inhibiting oxidative stress under high glucose(HG)conditions,this study is to specifically its mechanism of inhibiting apoptosis.Methods The mouse hippocampal neuron HT22 cells were placed in DME/F12 medium containing 10% fetal bovine serum(FBS)and 1% penicillin double antibody,in an incubator at 37°C and 5% CO2 in vitro.HT22 cells were divided into control group and several treatment groups.The control group was not specially treated.Several experimental groups were respectively added with different concentrations of glucose(25,50,100 m M)and different concentrations of salidroside(37.5,75,150,300 μM)at the points of 24,48 and 72 h.The enhanced CCK8 reagent was used to detect the effect of HT22 cell proliferation activity after 24,48,and 72 hours to screen the appropriate HG and SAL drug concentration;Flow cytometry and Hoechst 33342 staining were used to detect HT22 cell apoptosis;The mitochondrial membrane potential(MMP)kits was measured using a MMP assay kit with JC-1;The reactive oxygen species(ROS)kit was used to detect the changes in the content of ROS in HT22 cells after 48 hours of HG exposure;Western Blot was used to analyze the expression of p-NF-κB(p-p65),Bcl-2,Bax and cleaved Caspase-3 protein in HT22 cells after 48 hours of treatment.Results After forty eight hours high glucose treatment,the number of HT22 hippocampal neurons induced,the cell proliferation activity decreased significantly(P<0.01),the cell apoptosis rate increased significantly(P<0.01),intracellular ROS content increased significantly(P<0.01),mitochondrial membrane potential significantly decreased(P<0.01),the expression of p-p65,cleaved Caspase-3 and Bax protein in the cell increased(P<0.01),the expression of Bcl-2 protein in the cell was significantly decreased(P<0.01),the expression of Caspase-3 and Bax mRNA increased(P<0.01),and the expression of Bcl-2 mRNA decreased(P<0.01).Compared with HG group,the cell proliferation activity of HG+SAL group increased(P<0.01),cell apoptosis rate decreased(P<0.01),intracellular ROS content decreased(P<0.01)and mitochondrial membrane potential increased(P<0.01),the expression of p-p65,cleaved Caspase-3 and Bax protein in the cell increased(P<0.01),the expression of Bcl-2 protein in the cell decreased(P<0.05),and the expression of Caspase-3 and Bax mRNA increased(P<0.01),the expression of Bcl-2 mRNA decreased(P<0.01).Conclusion SAL inhibits the apoptosis of HT22 cells under high glucose condition,and its mechanism may be related to the inhibition of oxidative stress,inhibition of NF-κB phosphorylation,restoration of mitochondrial membrane potential,up-regulation of Bcl-2 protein expression and down-regulation of Bax and cleaved Caspase-3 protein expression.