Artificial gravity maintains skeletal muscle protein synthesis during 21 days of simulated microgravity

T. B. Symons, M. Sheffield-Moore, D. L. Chinkes, A. A. Ferrando, Douglas Paddon-Jones

Research output: Contribution to journalArticle

58 Citations (Scopus)

Abstract

We sought to determine the effects of longitudinal loading (artificial gravity) on skeletal muscle protein kinetics in 15 healthy young males after 21 days of 6° head-down tilt bed rest [experimental treatment (Exp) group: n = 8, 31 ± 1 yr; control (Con) group; n = 7, 28 ± 1 yr, means ± SE]. On days 1 and 21 of bed rest, postabsorptive venous blood samples and muscle biopsies (vastus lateralis and soleus) were obtained during a 1-h pulse bolus infusion protocol (0 min, L-[ring-13C6] phenylalanine, 35 μmol/kg; 30 min, L-[ring-15N]phenylalanine, 35 μmol/kg). Outcome measures included mixed muscle fractional synthesis (FSR) and breakdown rates (FBR). The Exp group experienced 1 h of longitudinal loading (2.5G at the feet) via a short-radius centrifuge during each day of bed rest. Mixed muscle FSR in the Con group was reduced by 48.5% (day 1, 0.081 ± 0.000%/h vs. day 21, 0.042 ± 0.000%/h; P = 0.001) in vastus lateralis after 21 days of bed rest, whereas the Exp group maintained their rate of protein synthesis. A similar but nonsignificant change in FSR was noted for the soleus muscle (Exp, -7%; Con, -22%). No changes in muscle protein breakdown were observed. In conclusion, 1 h of daily exposure to artificial gravity maintained the rate of protein synthesis of the vastus lateralis and may represent an effective adjunct countermeasure to combat the loss of muscle mass and functional during extended spaceflight.

Original languageEnglish (US)
Pages (from-to)34-38
Number of pages5
JournalJournal of Applied Physiology
Volume107
Issue number1
DOIs
StatePublished - Jul 2009

Fingerprint

Altered Gravity
Weightlessness
Bed Rest
Muscle Proteins
Quadriceps Muscle
Skeletal Muscle
Muscles
Phenylalanine
Head-Down Tilt
Space Flight
Control Groups
Foot
Proteins
Outcome Assessment (Health Care)
Biopsy

Keywords

  • Countermeasure
  • Muscle loss
  • Spaceflight
  • Stable isotopes

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Cite this

Artificial gravity maintains skeletal muscle protein synthesis during 21 days of simulated microgravity. / Symons, T. B.; Sheffield-Moore, M.; Chinkes, D. L.; Ferrando, A. A.; Paddon-Jones, Douglas.

In: Journal of Applied Physiology, Vol. 107, No. 1, 07.2009, p. 34-38.

Research output: Contribution to journalArticle

Symons, T. B. ; Sheffield-Moore, M. ; Chinkes, D. L. ; Ferrando, A. A. ; Paddon-Jones, Douglas. / Artificial gravity maintains skeletal muscle protein synthesis during 21 days of simulated microgravity. In: Journal of Applied Physiology. 2009 ; Vol. 107, No. 1. pp. 34-38.
@article{a460c5f8b7a54210b02589e1dcd3d90e,
title = "Artificial gravity maintains skeletal muscle protein synthesis during 21 days of simulated microgravity",
abstract = "We sought to determine the effects of longitudinal loading (artificial gravity) on skeletal muscle protein kinetics in 15 healthy young males after 21 days of 6° head-down tilt bed rest [experimental treatment (Exp) group: n = 8, 31 ± 1 yr; control (Con) group; n = 7, 28 ± 1 yr, means ± SE]. On days 1 and 21 of bed rest, postabsorptive venous blood samples and muscle biopsies (vastus lateralis and soleus) were obtained during a 1-h pulse bolus infusion protocol (0 min, L-[ring-13C6] phenylalanine, 35 μmol/kg; 30 min, L-[ring-15N]phenylalanine, 35 μmol/kg). Outcome measures included mixed muscle fractional synthesis (FSR) and breakdown rates (FBR). The Exp group experienced 1 h of longitudinal loading (2.5G at the feet) via a short-radius centrifuge during each day of bed rest. Mixed muscle FSR in the Con group was reduced by 48.5{\%} (day 1, 0.081 ± 0.000{\%}/h vs. day 21, 0.042 ± 0.000{\%}/h; P = 0.001) in vastus lateralis after 21 days of bed rest, whereas the Exp group maintained their rate of protein synthesis. A similar but nonsignificant change in FSR was noted for the soleus muscle (Exp, -7{\%}; Con, -22{\%}). No changes in muscle protein breakdown were observed. In conclusion, 1 h of daily exposure to artificial gravity maintained the rate of protein synthesis of the vastus lateralis and may represent an effective adjunct countermeasure to combat the loss of muscle mass and functional during extended spaceflight.",
keywords = "Countermeasure, Muscle loss, Spaceflight, Stable isotopes",
author = "Symons, {T. B.} and M. Sheffield-Moore and Chinkes, {D. L.} and Ferrando, {A. A.} and Douglas Paddon-Jones",
year = "2009",
month = "7",
doi = "10.1152/japplphysiol.91137.2008",
language = "English (US)",
volume = "107",
pages = "34--38",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "1",

}

TY - JOUR

T1 - Artificial gravity maintains skeletal muscle protein synthesis during 21 days of simulated microgravity

AU - Symons, T. B.

AU - Sheffield-Moore, M.

AU - Chinkes, D. L.

AU - Ferrando, A. A.

AU - Paddon-Jones, Douglas

PY - 2009/7

Y1 - 2009/7

N2 - We sought to determine the effects of longitudinal loading (artificial gravity) on skeletal muscle protein kinetics in 15 healthy young males after 21 days of 6° head-down tilt bed rest [experimental treatment (Exp) group: n = 8, 31 ± 1 yr; control (Con) group; n = 7, 28 ± 1 yr, means ± SE]. On days 1 and 21 of bed rest, postabsorptive venous blood samples and muscle biopsies (vastus lateralis and soleus) were obtained during a 1-h pulse bolus infusion protocol (0 min, L-[ring-13C6] phenylalanine, 35 μmol/kg; 30 min, L-[ring-15N]phenylalanine, 35 μmol/kg). Outcome measures included mixed muscle fractional synthesis (FSR) and breakdown rates (FBR). The Exp group experienced 1 h of longitudinal loading (2.5G at the feet) via a short-radius centrifuge during each day of bed rest. Mixed muscle FSR in the Con group was reduced by 48.5% (day 1, 0.081 ± 0.000%/h vs. day 21, 0.042 ± 0.000%/h; P = 0.001) in vastus lateralis after 21 days of bed rest, whereas the Exp group maintained their rate of protein synthesis. A similar but nonsignificant change in FSR was noted for the soleus muscle (Exp, -7%; Con, -22%). No changes in muscle protein breakdown were observed. In conclusion, 1 h of daily exposure to artificial gravity maintained the rate of protein synthesis of the vastus lateralis and may represent an effective adjunct countermeasure to combat the loss of muscle mass and functional during extended spaceflight.

AB - We sought to determine the effects of longitudinal loading (artificial gravity) on skeletal muscle protein kinetics in 15 healthy young males after 21 days of 6° head-down tilt bed rest [experimental treatment (Exp) group: n = 8, 31 ± 1 yr; control (Con) group; n = 7, 28 ± 1 yr, means ± SE]. On days 1 and 21 of bed rest, postabsorptive venous blood samples and muscle biopsies (vastus lateralis and soleus) were obtained during a 1-h pulse bolus infusion protocol (0 min, L-[ring-13C6] phenylalanine, 35 μmol/kg; 30 min, L-[ring-15N]phenylalanine, 35 μmol/kg). Outcome measures included mixed muscle fractional synthesis (FSR) and breakdown rates (FBR). The Exp group experienced 1 h of longitudinal loading (2.5G at the feet) via a short-radius centrifuge during each day of bed rest. Mixed muscle FSR in the Con group was reduced by 48.5% (day 1, 0.081 ± 0.000%/h vs. day 21, 0.042 ± 0.000%/h; P = 0.001) in vastus lateralis after 21 days of bed rest, whereas the Exp group maintained their rate of protein synthesis. A similar but nonsignificant change in FSR was noted for the soleus muscle (Exp, -7%; Con, -22%). No changes in muscle protein breakdown were observed. In conclusion, 1 h of daily exposure to artificial gravity maintained the rate of protein synthesis of the vastus lateralis and may represent an effective adjunct countermeasure to combat the loss of muscle mass and functional during extended spaceflight.

KW - Countermeasure

KW - Muscle loss

KW - Spaceflight

KW - Stable isotopes

UR - http://www.scopus.com/inward/record.url?scp=67650079061&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=67650079061&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.91137.2008

DO - 10.1152/japplphysiol.91137.2008

M3 - Article

VL - 107

SP - 34

EP - 38

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 1

ER -