Background:~Sarcopenia is a syndrome highly prevalent in the older population, characterized by muscle loss and a decrease in muscle strength. This leads to loss of physical function, decreased life quality and well-being and an increased risk of early death. Research has shown that both ingestion of protein and physical activity is able to diminish the loss of muscle mass during aging and thereby reduce the prevalence of sarcopenia and diminish the consequence of the disease. This study will investigate if more sustainable protein sources of good quality can increase the muscle protein synthesis and thereby prevent sarcopenia.~Aim:~The aim of this project is to investigate the effects of insect protein on the stimulation of muscle protein synthesis. The effects of protein will both be studied alone and in combination with exercise in perspective of preventing loss of both muscle mass and muscle strength. The potential of insect protein will be elucidated by comparison with other alternative plant-based protein sources in this case pea protein. In addition, whey protein will be included as a positive control as it may be regarded as the most established dietary protein source combatting muscle loss.~Method:~Young(18-30 years old) healthy men (n=60) are randomized in 3 groups to ingest either insect protein, pea protein or whey protein. Urine are collected 24 hours prior to the experiment while a blood sample and a muscle biopsy is collected at the beginning of the study. The subjects are instructed to perform one-leg exercise (knee extension, 5 sets of 10 repetitions, 10 repetitions-maximum) after which the subjects ingest the assigned protein bolus. Urine and blood samples are collected in the following hours and one muscle biopsy is collected from both the exercised and the non-exercised leg at 3 hours after protein ingestion. The expression of messenger RNA (mRNA) and protein related to the mTORC pathway in the muscle is investigated by qPCR and western blotting. In addition, metabolites in urine, blood plasma and muscle tissue are investigated by metabolomics analysis.
Randomized parallel study investing the effect of intake of different protein sources (whey, insect and pea) on the muscle protein synthesis. Activation of the signaling pathway leading to muscle protein synthesis is investigated by western blotting and Real time quantitative polymerase chain reaction (qPCR or PCR). Urine, blood and muscle is moreover investigated by metabolomics analysis.