Details
| Original language | English |
|---|---|
| Pages (from-to) | C300-C312 |
| Journal | American Journal of Physiology - Cell Physiology |
| Volume | 319 |
| Issue number | 2 |
| Publication status | Published - 8 Jan 2020 |
| Externally published | Yes |
Abstract
Skeletal muscle is a target of contraction-induced loading (CiL), leading to protein unfolding or cellular perturbations, respectively. While cytoskeletal desmin is responsible for ongoing structural stabilization, in the immediate response to CiL, alpha-crystallin B (CRYAB) is phosphorylated at serine 59 ( pCRYAB S59) by P38, acutely protecting the cytoskeleton. To reveal adaptation and deadaptation of these myofibrillar subsystems to CiL, we examined CRYAB, P38, and desmin regulation following resistance exercise at diverse time points of a chronic training period. Mechanosensitive JNK phosphorylation ( pJNK T183/ Y185) was determined to indicate the presence of mechanical components in CiL. Within 6 wk, subjects performed 13 resistance exercise bouts at the 8–12 repetition maximum, followed by 10 days detraining and a final 14th bout. Biopsies were taken at baseline and after the 1st, 3rd, 7th, 10th, 13th, and 14th bout. To assess whether potential desensitization to CiL can be mitigated, one group trained with progressive and a second with constant loading. As no group differences were found, all subjects were combined for statistics. Total and phosphorylated P38 was not regulated over the time course. pCRYAB S59 and pJNK T183/Y185 strongly increased following the unaccustomed first bout. This exercise-induced pCRYAB S59/ pJNK T183/Y185 increase disappeared with the 10th until 13th bout. As response to the detraining period, the 14th bout led to a renewed increase in pCRYAB S59. Desmin content followed pCRYAB S59 inversely, i.e., was up- when pCRYAB S59 was downregulated and vice versa. In conclusion, the pCRYAB S59 response indicates increase and decrease in resistance to CiL, in which a reinforced desmin network could play an essential role by structurally stabilizing the cells.
Keywords
- CRYAB, Desmin, Mechanical stress, Muscle, Resistance exercise
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Physiology
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology
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In: American Journal of Physiology - Cell Physiology, Vol. 319, No. 2, 08.01.2020, p. C300-C312.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Coordinated alpha-crystallin B phosphorylation and desmin expression indicate adaptation and deadaptation to resistance exercise-induced loading in human skeletal muscle
AU - Jacko, Daniel
AU - Bersiner, Käthe
AU - Schulz, Oliver
AU - Przyklenk, Axel
AU - Spahiu, Fabian
AU - Höhfeld, Jörg
AU - Bloch, Wilhelm
AU - Gehlert, Sebastian
N1 - Publisher Copyright: Copyright © 2020 the American Physiological Society
PY - 2020/1/8
Y1 - 2020/1/8
N2 - Skeletal muscle is a target of contraction-induced loading (CiL), leading to protein unfolding or cellular perturbations, respectively. While cytoskeletal desmin is responsible for ongoing structural stabilization, in the immediate response to CiL, alpha-crystallin B (CRYAB) is phosphorylated at serine 59 ( pCRYAB S59) by P38, acutely protecting the cytoskeleton. To reveal adaptation and deadaptation of these myofibrillar subsystems to CiL, we examined CRYAB, P38, and desmin regulation following resistance exercise at diverse time points of a chronic training period. Mechanosensitive JNK phosphorylation ( pJNK T183/ Y185) was determined to indicate the presence of mechanical components in CiL. Within 6 wk, subjects performed 13 resistance exercise bouts at the 8–12 repetition maximum, followed by 10 days detraining and a final 14th bout. Biopsies were taken at baseline and after the 1st, 3rd, 7th, 10th, 13th, and 14th bout. To assess whether potential desensitization to CiL can be mitigated, one group trained with progressive and a second with constant loading. As no group differences were found, all subjects were combined for statistics. Total and phosphorylated P38 was not regulated over the time course. pCRYAB S59 and pJNK T183/Y185 strongly increased following the unaccustomed first bout. This exercise-induced pCRYAB S59/ pJNK T183/Y185 increase disappeared with the 10th until 13th bout. As response to the detraining period, the 14th bout led to a renewed increase in pCRYAB S59. Desmin content followed pCRYAB S59 inversely, i.e., was up- when pCRYAB S59 was downregulated and vice versa. In conclusion, the pCRYAB S59 response indicates increase and decrease in resistance to CiL, in which a reinforced desmin network could play an essential role by structurally stabilizing the cells.
AB - Skeletal muscle is a target of contraction-induced loading (CiL), leading to protein unfolding or cellular perturbations, respectively. While cytoskeletal desmin is responsible for ongoing structural stabilization, in the immediate response to CiL, alpha-crystallin B (CRYAB) is phosphorylated at serine 59 ( pCRYAB S59) by P38, acutely protecting the cytoskeleton. To reveal adaptation and deadaptation of these myofibrillar subsystems to CiL, we examined CRYAB, P38, and desmin regulation following resistance exercise at diverse time points of a chronic training period. Mechanosensitive JNK phosphorylation ( pJNK T183/ Y185) was determined to indicate the presence of mechanical components in CiL. Within 6 wk, subjects performed 13 resistance exercise bouts at the 8–12 repetition maximum, followed by 10 days detraining and a final 14th bout. Biopsies were taken at baseline and after the 1st, 3rd, 7th, 10th, 13th, and 14th bout. To assess whether potential desensitization to CiL can be mitigated, one group trained with progressive and a second with constant loading. As no group differences were found, all subjects were combined for statistics. Total and phosphorylated P38 was not regulated over the time course. pCRYAB S59 and pJNK T183/Y185 strongly increased following the unaccustomed first bout. This exercise-induced pCRYAB S59/ pJNK T183/Y185 increase disappeared with the 10th until 13th bout. As response to the detraining period, the 14th bout led to a renewed increase in pCRYAB S59. Desmin content followed pCRYAB S59 inversely, i.e., was up- when pCRYAB S59 was downregulated and vice versa. In conclusion, the pCRYAB S59 response indicates increase and decrease in resistance to CiL, in which a reinforced desmin network could play an essential role by structurally stabilizing the cells.
KW - CRYAB
KW - Desmin
KW - Mechanical stress
KW - Muscle
KW - Resistance exercise
UR - http://www.scopus.com/inward/record.url?scp=85088495380&partnerID=8YFLogxK
U2 - DOI: 10.1152/ajpcell.00087.2020
DO - DOI: 10.1152/ajpcell.00087.2020
M3 - Article
VL - 319
SP - C300-C312
JO - American Journal of Physiology - Cell Physiology
JF - American Journal of Physiology - Cell Physiology
SN - 0363-6143
IS - 2
ER -