A cell-based evaluation of a non-essential amino acid formulation as a non-bioactive control for activation and stimulation of muscle protein synthesis using ex vivo human serum

Autoři: Bijal Patel aff001;  Martina Pauk aff001;  Miryam Amigo-Benavent aff001;  Alice B. Nongonierma aff001;  Richard J. Fitzgerald aff001;  Philip M. Jakeman aff001;  Brian P. Carson aff001
Působiště autorů: Food for Health Ireland, University of Limerick, Limerick, Ireland aff001;  Human Sciences Research Unit, University of Limerick, Limerick, Ireland aff002;  Department of Physical Education & Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland aff003;  Centre for Intervention in Infection, Inflammation and Immunity (4i), University of Limerick, Limerick, Ireland aff004;  Department of Biological Sciences, University of Limerick, Limerick, Ireland aff005;  Health Research Institute, University of Limerick, Limerick, Ireland aff006
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0220757



The purpose of this study was to compare the effect of treating skeletal muscle cells with media conditioned by postprandial ex vivo human serum fed with either isonitrogenous Non-Essential Amino Acid (NEAA) or a whey protein hydrolysate (WPH) on stimulating Muscle Protein Synthesis (MPS) in C2C12 skeletal muscle cells.


Blood was taken from six young healthy males following overnight fast (fasted) and 60 min postprandial (fed) ingestion of either WPH or NEAA (0.33 g.kg-1 Body Mass). C2C12 myotubes were treated with media conditioned by ex vivo human serum (20%) for 4 h. Activation of MPS signalling (phosphorylation of mTOR, P70S6K and 4E-BP1) were determined in vitro by Western Blot and subsequent MPS were determined in vitro by Western Blot and surface sensing of translation technique (SUnSET) techniques, respectively.


Media conditioned by NEAA fed serum had no effect on protein signalling or MPS compared to fasted, whereas media conditioned by WPH fed serum significantly increased mTOR (Ser2448), P70S6K and 4E-BP1 phosphorylation (p<0.01, p<0.05) compared to fasted serum. Furthermore, the effect of media conditioned by WPH fed serum on protein signalling and MPS was significantly increased (p<0.01, p<0.05) compared to NEAA fed serum.


In summary, media conditioned by NEAA fed serum did not result in activation of MPS. Therefore, these in vitro findings suggest the use of isonitrogenous NEAA acts as an effective control for comparing bioactivity of different proteins on activation of MPS.

Klíčová slova:

Ingestion – Insulin – Muscle proteins – Phosphorylation – Serum proteins – Skeletal muscles – Muscle protein synthesis – Leucine


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