DHA Inhibits Protein Degradation More Efficiently than EPA by Regulating the PPARγ/NFκB Pathway in C2C12 Myotubes
Figure 5
Effect of n-3 PUFA on the IκBα /NFκB complex in C2C12 myotubes knockdown of PPARγ. The C2C12 myotubes transfected with PPARγ Stealth RNAi oligonucleotide were incubated with 600 μM EPA or 600 μM DHA for 24 hours, respectively. BSA was used as fatty acid-free control. Protein extracts from C2C12 myotubes were assayed for western blot analysis with p-IκBα, IκBα, or -actin (Figure 5(a)). The band on the western blot represented a protein with a molecular mass of ~37 kDa as determined by the molecular mass markers included in the experiment. Total nuclear protein was subsequently isolated and analyzed by EMSA for NFκB DNA binding activity using a 32P-labeled double-stranded oligonucleotide of the NFκB (Figure 5(b)). An additional unlabeled probe was added in the competition assay (cold). Data are representative of three experiments. BSA = bovine serum albumin, DHA = docosahexaenoic acid, EPA = eicosapentaenoic acid, and p-IκBα = phosphorylated IκBα.
