Hypoxia alters contractile protein homeostasis in L6 myotubes.
Since hypoxia might contribute to the development of muscle atrophy, we wished to provide direct evidence linking hypoxia to muscle atrophy. By evaluating protein degradation and synthesis in hypoxic myotubes we found a significant reduction in total protein content. Using functional assays we observed protein degradation elevation in the first 24 h while synthesis was maintained during this period and then significantly decrease at 48 h. These results demonstrate a temporal regulation of protein homeostasis, whereby elevated protein degradation is followed by a reduction in synthesis. These results are comparable to the cellular adaptation seen during development of muscle atrophy.
Centre de recherche de l' Institut Universitaire de Cardiologie et de Pneumologie de l'Université Laval, 2725 Chemin Ste-Foy, Quebec City, QC, Canada, G1V 4G5.
Marc-André
MA
Caron
Marie-Eve
ME
Thériault
Marie-Eve
ME
Paré
François
F
Maltais
Richard
R
Debigaré
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D015687:Cell Hypoxia; D002460:Cell Line; D017931:DNA Primers; D006706:Homeostasis; D006868:Hydrolysis; D009119:Muscle Contraction; D018485:Muscle Fibers, Skeletal / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D051381:Rats
D017931:DNA Primers; D009124:Muscle Proteins