@article{FernandoDrescherDeubeletal.2018,
  author    = {Fernando, Raquel and Drescher, Cathleen and Deubel, Stefanie and Jung, Tobias and Ost, Mario and Klaus, Susanne and Grune, Tilman and Castro, Jose Pedro},
  title     = {Low proteasomal activity in fast skeletal muscle fibers is not associated with increased age-related oxidative damage},
  series = {Experimental gerontology},
  volume    = {117},
  journal   = {Experimental gerontology},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0531-5565},
  doi       = {10.1016/j.exger.2018.10.018},
  pages     = {45 -- 52},
  year      = {2018},
  abstract  = {The skeletal muscle is a crucial tissue for maintaining whole body homeostasis. Aging seems to have a disruptive effect on skeletal muscle homeostasis including proteostasis. However, how aging specifically impacts slow and fast twitch fiber types remains elusive. Muscle proteostasis is largely maintained by the proteasomal system. Here we characterized the proteasomal system in two different fiber types, using a non-sarcopenic aging model. By analyzing the proteasomal activity and amount, as well as the polyubiquitinated proteins and the level of protein oxidation in Musculus soleus (Sol) and Musculus extensor digitorum longus (EDL), we found that the slow twitch Sol muscle shows an overall higher respiratory and proteasomal activity in young and old animals. However, especially during aging the fast twitch EDL muscle reduces protein oxidation by an increase of antioxidant capacity. Thus, under adaptive non-sarcopenic conditions, the two fibers types seem to have different strategies to avoid age-related changes.},
  language  = {en}
}
@misc{FernandoDrescherDeubeletal.2018,
  author    = {Fernando, Raquel and Drescher, Cathleen and Deubel, Stefanie and Grune, Tilman and Castro, Jose Pedro},
  title     = {Distinct proteasomal activity for fast and slow twitch skeletal muscle during aging},
  series = {Free radical biology and medicine : the official journal of the Oxygen Society, a constituent member of the International Society for Free Radical Research},
  volume    = {120},
  journal   = {Free radical biology and medicine : the official journal of the Oxygen Society, a constituent member of the International Society for Free Radical Research},
  publisher = {Elsevier},
  address   = {New York},
  issn      = {0891-5849},
  doi       = {10.1016/j.freeradbiomed.2018.04.393},
  pages     = {S119 -- S119},
  year      = {2018},
  abstract  = {Skeletal muscle alterations during aging lead to dysfunctional metabolism, correlating with frailty and early mortality. The loss of proteostasis is a hallmark of aging. Whether proteostasis loss plays a role in muscle aging remains elusive. To address this question we collected muscles, Soleus (SOL, type I) and Extensor digitorum longus (EDL, type II), from young (4 months) and old (25 months) C57BL/6 mice and evaluated the proteasomal system. Initial work showed decreased 26 S activity in old SOL. EDL displayed lower proteasomal activity in both ages compared to any of the SOL ages. Moreover, in order to understand if during aging there is the so-called "fiber switch from fast-to-slow", we performed western blots against sMHC and fMHC (slow and fast myosin heavy chain, respectively). Preliminary results suggest that young SOL is composed by slow twitch fibers but also contains fast twitch fibers, while young EDL seems to be mostly composed by fast twitch fibers that level down during aging, suggesting the switch. As a conclusion, EDL seems to have less proteasomal activity, however, if this is a contributor or a consequence to the muscle fiber switch during aging still needs further investigation.},
  language  = {en}
}