| Autor: |
Howard EE; Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA.; Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, USA.; Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA., Margolis LM; Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, USA., Fussell MA; Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA., Rios CG; Orthopedic Associates of Hartford Surgery Center, Glastonbury, CT 06033, USA., Meisterling EM; Integrated Anesthesia Associates, Hartford, CT 06106, USA., Lena CJ; Orthopedic Associates of Hartford Surgery Center, Glastonbury, CT 06033, USA., Pasiakos SM; Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, USA., Rodriguez NR; Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA. |
| Abstrakt: |
Increasing dietary protein intake during periods of muscle disuse may mitigate the resulting decline in muscle protein synthesis (MPS). The purpose of this randomized pilot study was to determine the effect of increased protein intake during periods of disuse before anterior cruciate ligament (ACL) reconstruction on myofibrillar protein synthesis (MyoPS), and proteolytic and myogenic gene expression. Six healthy, young males (30 ± 9 y) were randomized to consume a high-quality, optimal protein diet (OP; 1.9 g·kg−1·d−1) or adequate protein diet (AP; 1.2 g·kg−1·d−1) for two weeks before ACL reconstruction. Muscle biopsies collected during surgery were used to measure integrated MyoPS during the intervention (via daily deuterium oxide ingestion) and gene expression at the time of surgery. MyoPS tended to be higher, with a large effect size in OP compared to AP (0.71 ± 0.1 and 0.54 ± 0.1%·d−1; p = 0.076; g = 1.56). Markers of proteolysis and myogenesis were not different between groups (p > 0.05); however, participants with greater MyoPS exhibited lower levels of MuRF1 gene expression compared to those with lower MyoPS (r = −0.82, p = 0.047). The data from this pilot study reveal a potential stimulatory effect of increased daily protein intake on MyoPS during injury-mediated disuse conditions that warrants further investigation. |
