title: Akt-dependent and Akt-independent pathways are involved in protein synthesis activation during reloading of disused soleus muscle.
abstract: The purpose of our study was to assess the contribution of insulin growth factor-1-dependent and phosphatidic acid-dependent signaling pathways to activation of protein synthesis (PS) in rat soleus muscle during early recovery from unloading.
  
  
  
  Wistar rats were divided into: Control, 14HS [14-day hindlimb suspension (HS)], 3R+placebo (3-day reloading + saline administration), 3R+Wort (3-day reloading + wortmannin administration), 3R+But (3-day reloading + 1-butanol administration). SUnSET and Western blot analyses were used in this study.
  
  
  
  Wortmannin and 1-butanol induced a decrease in protein kinase B (phospho-Akt) and the rate of PS (P < 0.05) versus Control. In 3R+placebo and 3R+Wort, phosphorylation of glycogen synthase kinase 3 beta (phospho-GSK-3β) was increased versus Control (P < 0.05). Wortmannin administration during reloading did not alter phospho-p70S6K (70 kDa ribosomal protein S6 kinase) versus 3R+placebo. In 3R+But, there was a decline in phospho-GSK-3β versus 3R+placebo and Control. In 3R+But, there was a decrease in phopho-p70S6K (P < 0.05) versus 3R+placebo.
  
  
  
  These results suggest that PS activation during 3-day reloading following 14HS involves both Akt-dependent and Akt-independent pathways. Muscle Nerve 55: 393-399, 2017.
authors.affiliation: Myology Laboratory, Institute of Bio-Medical Problems of the Russian Academy of Sciences, 123007, Moscow, Russian Federation.
authors.forename: Timur M
authors.initials: TM
authors.lastname: Mirzoev
authors.affiliation: Myology Laboratory, Institute of Bio-Medical Problems of the Russian Academy of Sciences, 123007, Moscow, Russian Federation.
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Tyganov
authors.affiliation: Myology Laboratory, Institute of Bio-Medical Problems of the Russian Academy of Sciences, 123007, Moscow, Russian Federation.
authors.forename: Boris S
authors.initials: BS
authors.lastname: Shenkman
mesh_terms: D020001:1-Butanol / Q000494:pharmacology; D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D019417:Hindlimb Suspension / Q000502:physiology; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology*; D051058:Oncogene Protein v-akt / Q000378:metabolism*; D009929:Organ Size / Q000187:drug effects; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D014176:Protein Biosynthesis / Q000187:drug effects / Q000502:physiology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011691:Puromycin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013997:Time Factors; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; D010726:Phosphodiesterase Inhibitors; D011500:Protein Synthesis Inhibitors; D011691:Puromycin; D007334:Insulin-Like Growth Factor I; D020001:1-Butanol; D051058:Oncogene Protein v-akt; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D000077191:Wortmannin
keywords: Akt; GSK-3β; disuse atrophy; p70S6K; protein synthesis; reloading; soleus muscle