The Role Of Oleic Acid On The Expression Of PGC-1α In Mouse C2C12Cells And Its Regulation Mechanism

Objective：To investigate the effect of Oleic acid on the expression of PGC-1α mRNA andprotein in mouse c2c12cells and to unravel the associated mechanism of the process,further clarify the mechanism of insulin resistance induced by obesity.Methods:Cultured c2c12cells were used for the experiment to investigate the effect ofOleic acid on the expression of PGC-1α in c2c12cells and to unravel the mechanism.①Treated cells by different concentration (0.1、0.2、0.5、1.0mmol/L) of Oleic acid for6h and12h respectively, the expression of PGC-1α mRNA was detected by RT-PCR.②Treated cells by different concentration (0.1、0.2、0.5、1.0mmol/L) of Oleic acid for12h, the morphological changes and apoptosis rate were detected by invertedmicroscope and flow cytometry.③Treated cells by0.1and0.2mmol/L Oleic acid for30minutes, the expression of phosphorylated p38MAPK was detected by WesternBlot.④0.2mmol/L Oleic acid with20μmol/L SB203580(inhibitor of p38MAPK)treated cells for12h, the expression of PGC-1α mRNA and protein were detected byRT-PCR and Western Blot.⑤Transfected by Wild type and five kinds of pointmutation PGC-1α plasmids for6h, the activity of PGC-1α promoter were detected byLuciferase.0.2mmol/L Oleic acid with20μmol/L SB203580(inhibitor of p38MAPK)treated the cells which transfected by Wild type and five kind of point mutationplasmid for6h, the activity of PGC-1α promoter were detected by Luciferase.Results:1. Mouse c2c12cells were treated by different concentration of Oleic acid for6hrespectively, compared with each group, the expression of PGC-1α mRNA did notchange significantly. The same factors treated for12h, compared with the control group, the expression of PGC-1α mRNA was increased at the0.2mmol/L group anddecreased at the1.0mmol/L group.2. Mouse c2c12cells were treated by different concentration of Oleic acid for12h respectively, compared with the control group,0.1mmol/L group and0.2mmol/Lgroup, the number of dead cells and the rate of apoptosis were increased at the Oleicacid concentrations of0.5mmol/L group and1.0mmol/L group, and the rate ofincreased was the highest at the1.0mmol/L group.3. Mouse c2c12cells were treated by the Oleic acid concentrations of0.1mmol/Land0.2mmol/L group for30minutes, compared with the control group, the expressionof phosphorylated p38MAPK was did not change significantly at the0.1mmol/Lgroup, but it was increased at the0.2mmol/L group.4. Compared with the control group, the expression of PGC-1α mRNA andprotein were increased at the0.2mmol/L Oleic acid group. Compared with the0.2mmol/L Oleic acid group, the expression of PGC-1α mRNA and protein weredecreased at the0.2mmol/L Oleic acid with20μmol/L SB203580group.5. Mouse c2c12cells were transfected by Wild type or point mutationCRE/Mef2/CRE+Mef2/IREs/CMRs plasmids for6h respectively, the activity ofPGC-1α promoter at those point mutation type groups lower than the Wild type group,especially in inactivated the CRE response element groups.6. The activity of PGC-1α promoters were increased, compared with the withoutOleic acid group, which groups were transfected by0.2mmol/L Oleic acid with Wildtype or point mutation type plasmids for6h respectively. When inactivated theCRE/Mef2response elements, the rate of increase were lower than other pointmutation groups. Transfected cells were treated by0.2mmol/L Oleic acid with20μmol/L SB203580after, the activity of promoter were lower than the0.2mmol/LOleic acid groups.Conclusions:1. The expression of PGC-1α mRNA and protein in mouse c2c12cells wereincreased at the0.2mmol/L Oleic acid for12h. The expression of PGC-1α mRNA were decreased at the concentration of0.5mmol/L and1.0mmol/L Oleic acid groupscould be related to the apoptosis.2. The treatment of Oleic acid could increase the expression of phosphorylatedp38MAPK in mouse c2c12cells. The effect of Oleic acid on the expression ofPGC-1α gene in mouse c2c12cells might be related to p38MAPK signing pathways.3. The activity of PGC-1α promoter mainly depends on the CRE responseelement. The effect of Oleic acid on the expression of PGC-1α gene in mouse c2c12cells might be related to the CRE and Mef2response elements.