Role of in Glucose Uptake and Fatty Acid Metabolism in C2C12 Skeletal Myotubes.

Acyl-coenzyme A (CoA):diacylglycerol acyltransferase 2 (DGAT2) catalyzes the last stage of triacylglycerol (TAG) synthesis, a process that forms ester bonds with diacylglycerols (DAG) and fatty acyl-CoA substrates. The enzymatic role of has been studied in various biological species. Still, the full description of how channels fatty acids in skeletal myocytes and the consequence thereof in glucose uptake have yet to be well established. Therefore, this study explored the mediating role of in glucose uptake and fatty acid partitioning under short interfering ribonucleic acid (siRNA)-mediated knockdown conditions. Cells transfected with siRNA downregulated glucose transporter type 4 () messenger RNA (mRNA) expression and decreased the cellular uptake of [1-C]-labeled 2-deoxyglucose up to 24.3% ( < 0.05). Suppression of deteriorated insulininduced Akt phosphorylation. siRNA reduced [1-C]-labeled oleic acid incorporation into TAG, but increased the level of [1-C]-labeled free fatty acids at 3 h after initial fatty acid loading. In an experiment of chasing radioisotope-labeled fatty acids, suppression augmented the level of cellular free fatty acids. It decreased the level of re-esterification of free fatty acids to TAG by 67.6% during the chase period, and the remaining pulses of phospholipids and cholesteryl esters were decreased by 34.5% and 61%, respectively. Incorporating labeled fatty acids into beta-oxidation products increased in siRNA transfected cells without gene expression involving fatty acid oxidation. These results indicate that has regulatory function in glucose uptake, possibly through the reaction of TAG with endogenously released or recycled fatty acids.