Robinson 2019 Am J Physiol Cell Physiol
|Robinson MM, Sather BK, Burney ER, Ehrlicher SE, Stierwalt HD, Franco MC, Newsom SA (2019) Robust intrinsic differences in mitochondrial respiration and H2O2 emission between L6 and C2C12 cells. Am J Physiol Cell Physiol 317:C339-C347.|
Abstract: Rat L6 and mouse C2C12 cell lines are commonly used to investigate myocellular metabolism. Mitochondrial characteristics of these cell lines remains poorly understood despite mitochondria being implicated in development of various metabolic diseases. To address this need we performed high-resolution respirometry to determine rates of oxygen consumption and hydrogen peroxide (H2O2) emission in suspended myoblasts during multiple substrate and inhibitor titration protocols. The capacity for oxidative phosphorylation supported by glutamate and malate, with and without succinate, or supported by palmitoyl-L-carnitine was lower in L6 compared with C2C12 myoblasts (all P<0.01 for L6 vs. C2C12). Conversely, H2O2 emission during oxidative phosphorylation was greater in L6 than C2C12 myoblasts (P<0.01 for L6 vs. C2C12). Induction of non-coupled respiration revealed a significantly greater electron transfer capacity in C2C12 compared with L6 myoblasts, regardless of the substrate(s) provided. Mitochondrial metabolism was also investigated in differentiated L6 and C2C12 myotubes. Basal rates of oxygen consumption were not different between intact, adherent L6 and C2C12 myotubes; however, non-coupled respiration was significantly lower in L6 compared with C2C12 myotubes (P<0.001). In summary, L6 myoblasts had lower respiration rates than C2C12 myoblasts, including lesser capacity for fatty acid oxidation and greater electron leak towards H2O2. L6 cells also retain a lower capacity for electron transfer compared with C2C12 following differentiation to form fused myotubes. Intrinsic differences in mitochondrial metabolism between these cell lines should be considered when modeling and investigating myocellular metabolism.
• Keywords: Electron transfer system, Lipid oxidation, Muscle cells, Reactive oxygen species, Rat L6 myoblasts, Mouse C2C12 myoblasts • Bioblast editor: Plangger M • O2k-Network Lab: US OR Corvallis Robinson MM
Labels: MiParea: Respiration, Comparative MiP;environmental MiP
Organism: Mouse, Rat Tissue;cell: Skeletal muscle Preparation: Permeabilized cells Enzyme: Complex I, Complex II;succinate dehydrogenase, Complex III, Complex IV;cytochrome c oxidase, Complex V;ATP synthase
Coupling state: LEAK, OXPHOS, ET Pathway: F, N, S, Gp, NS, Other combinations, ROX HRR: Oxygraph-2k, O2k-Fluorometer