Electrically stimulated contractile activity-induced transcriptomic responses and metabolic remodeling in C2C12 myotubes: twitch vs. tetanic contractions.
The contraction of myotubes using electrical pulse stimulation is a research tool used to mimic muscle contractile activity and exercise in rodents and humans. Most protocols employed in previous work used low-frequency twitch contractions. However, high-frequency tetanus contractions that are more physiologically relevant to muscle contractions in vivo are poorly characterized. In this report, the similarities and differences in acute responses and chronic adaptations with different contractile modes using twitches (2 Hz, continuous, 3 h) and tetanus (66 Hz, on: 5 s/off: 5 s, 3 h) were investigated. RNA sequencing-based transcriptome analysis and subsequent bioinformatics analysis suggest that tetanus may promote bioenergetic remodeling rather than twitch. Based on in silico analyses, metabolic remodeling after three contractile sessions of twitch and tetanus were investigated. Although twitch and tetanus had no significant effect on glycolysis, both types of contraction upregulated glucose oxidation capacity. Both twitch and tetanus qualitatively caused mitochondrial adaptations (increased content, respiratory chain enzyme activity, and respiratory function). The magnitude of adaptation was much greater under tetanus conditions. Our findings indicate that the contraction of myotubes by tetanus may be a useful experimental model, especially in the study of metabolic adaptations in C2C12 myotubes.
['Tamura|Yuki|Y|0000-0003-0317-5343', 'Kouzaki|Karina|K|', 'Kotani|Takaya|T|', 'Nakazato|Koichi|K|0000-0002-2479-5771']
D000818:Animals D002460:Cell Line D004558:Electric Stimulation D020869:Gene Expression Profiling D005947:Glucose D006003:Glycogen D006019:Glycolysis D019344:Lactic Acid D051379:Mice D008810:Mice, Inbred C57BL D008928:Mitochondria D009119:Muscle Contraction D018485:Muscle Fibers, Skeletal D018482:Muscle, Skeletal D010084:Oxidation-Reduction D010805:Physical Conditioning, Animal D012032:Refractory Period, Electrophysiological D059467:Transcriptome
transcriptome myotubes electrical pulse stimulation glycolysis mitochondria skeletal muscle