Abstract
Heat shock protein 70 is known to inhibit muscle atrophy in in vitro and in vivo models. The goal of this study was to investigate whether a herbal compound celastrol (CEL) promoted HSP70 overexpression via activation of heat shock transcription factor 1 (HSF1) in C2C12 myotubes. The HSP70 expression was increased in a time-dependent manner with 5.8- to 9.1-fold upregulation at ≥ 4 h after 1.5 µM CEL treatment. Nuclear accumulation of phospho-HSF1 was evident at ≥ 2 h over the 6-h CEL treatment. Phosphorylation of Akt1 (the protein anabolic marker) was also increased 3.5- to 6.6- fold at ≥ 2 h while total Akt1 expression was not changed over the CEL treatment. These results imply that CEL has a potency to inhibit muscle atrophy via HSP70 induction and Akt1 activation. The results will be used for development of a protocol for a future ISS/JEM onboard experiment.
