Relationship between microRNA-93-5p and mitochondrial fusion protein-2 in mouse nerve cells subjected to oxygen-glucose deprivation and reoxygenation / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the relationship between microRNA-93-5p and mitochondrial fusion protein-2 (Mfn2) in mouse nerve cells subjected to oxygen-glucose deprivation and reoxygenation (OGD/R).Methods:Mouse neuroblastoma cells were cultured in vitro to logarithmic growth phase.Experiment Ⅰ Cells were divided into 5 groups ( n=20 each) by the random number table method: control group (group C), group OGD/R, miR-93-5p inhibitor group (group I), siRNA-mfn2 plus miR-93-5p group (group siMfn2+ I) and miR-93-5p negative control group (group NC). Oxygen-glucose deprivation the cells were cultured for 3 h in a low-glucose balanced salt solution at 37 ℃ in an environment of 5% CO 2-95% N 2.Restoration of oxygen and glucose the cells were cultured in normal medium at 37℃ in 5% CO 2-95% air for 24 h. Group I, group siMfn2+ I and group NC were transfected with miR-93-5p inhibitor, miR-93-5p inhibitor plus siRNA-mfn2 and negative control miRNA, respectively, at 48 h before the OGD/R model was developed.Cell viability was measured by CCK-8 assay.Cell apoptosis rate was measured by flow cytometry.Quantitative real-time polymerase chain reaction was used to detect the expression of miR-93-5p and Mfn2 mRNA.Western blot was used to detect Mfn2 protein expression.Experiment Ⅱ The wild-type (WT)-Mfn2 and mutant (MUT)-Mfn2 were constructed and transfected into neuroblastoma cells with miR-93-5p mimic and miR-93-5p blank control (miR-93-5pNC), respectively.The cells were divided into 4 groups ( n=5 each) after 48 h of transfection by the random number table method: miR-93-5p NC-WT-Mfn2 co-transfection group, miR-93-5p mimic-WT-Mfn2 co-transfection group, miR-93-5p NC-MUT-Mfn2 co-transfection group, and miR-93-5p mimic-MUT-Mfn2 co-transfection group.The activity of luciferases was measured by double luciferase assay. Results:Experiment Ⅰ Compared with group C, the cell viability was significantly decreased, the apoptosis rate of cells was increased, the expression of miR-93-5p was up-regulated, and the expression of Mfn2 protein and mRNA was down-regulated in the other gorups ( P<0.05). Compared with group OGD/R or group NC, the cell viability was significantly increased, the apoptosis rate of cells was decreased, miR-93-5p expression was down-regulated, and the expression of Mfn2 protein and mRNA was up-regulated in group I ( P<0.05). Compared with group I, the cell viability was significantly decreased, the apoptosis rate of cells was increased, and the expression of Mfn2 protein and mRNA was down-regulated in group siMfn2+ I ( P<0.05). Experiment Ⅱ Compared with miR-93-5p NC-WT-Mfn2 co-transfection group, the luciferase activity was significantly decreased in miR-93-5p mimic-WT-Mfn2 co-transfection group ( P<0.05). There was no significant difference in luciferase activity between miR-93-5p NC-MUT-Mfn2 co-transfection group and miR-93-5p mimic-MUT-Mfn2 co-transfection group ( P>0.05). Conclusions:The miR-93-5p expression is up-regulated, which further targetedly down-regulates the expression of Mfn2, and this may be a mechanism of OGD/R in mouse nerve cells.