Mycoprotein ingestion stimulates protein synthesis rates to a greater extent than milk protein in rested and exercised skeletal muscle of healthy young men: a randomized controlled trial

Abstract

Background Mycoprotein is a fungal-derived sustainable protein-rich food source, and its ingestion results in systemic amino acid and leucine concentrations similar to that following milk protein ingestion. Objective We assessed the mixed skeletal muscle protein synthetic response to the ingestion of a single bolus of mycoprotein compared with a leucine-matched bolus of milk protein, in rested and exercised muscle of resistance-trained young men. Methods Twenty resistance-trained healthy young males (age: 22 ± 1 y, body mass: 82 ± 2 kg, BMI: 25 ± 1 kg·m−2) took part in a randomized, double-blind, parallel-group study. Participants received primed, continuous infusions of L-[ring-2H5]phenylalanine and ingested either 31 g (26.2 g protein: 2.5 g leucine) milk protein (MILK) or 70 g (31.5 g protein: 2.5 g leucine) mycoprotein (MYCO) following a bout of unilateral resistance-type exercise (contralateral leg acting as resting control). Blood and m. vastus lateralis muscle samples were collected before exercise and protein ingestion, and following a 4-h postprandial period to assess mixed muscle fractional protein synthetic rates (FSRs) and myocellular signaling in response to the protein beverages in resting and exercised muscle. Results Mixed muscle FSRs increased following MILK ingestion (from 0.036 ± 0.008 to 0.052 ± 0.006%·h−1 in rested, and 0.035 ± 0.008 to 0.056 ± 0.005%·h−1 in exercised muscle; P <0.01) but to a greater extent following MYCO ingestion (from 0.025 ± 0.006 to 0.057 ± 0.004%·h−1 in rested, and 0.024 ± 0.007 to 0.072 ± 0.005%·h−1 in exercised muscle; P <0.0001) (treatment × time interaction effect; P <0.05). Postprandial FSRs trended to be greater in MYCO compared with MILK (0.065 ± 0.004 compared with 0.054 ± 0.004%·h−1, respectively; P = 0.093) and the postprandial rise in FSRs was greater in MYCO compared with MILK (Delta 0.040 ± 0.006 compared with Delta 0.018 ± 0.005%·h−1, respectively; P <0.01). Conclusions The ingestion of a single bolus of mycoprotein stimulates resting and postexercise muscle protein synthesis rates, and to a greater extent than a leucine-matched bolus of milk protein, in resistance-trained young men. This trial was registered at clinicaltrials.gov as 660065600.

Dampened Muscle mTORC1 Response Following Ingestion of High-Quality Plant-Based Protein and Insect Protein Compared to Whey

“…Numerous studies have shown potent activation of downstream mTORC1 signalling with whole animal-based protein sources [ 28 , 45 , 46 ], but data on mTORC1 activation with non-animal-based protein blends is scarce. Recent human data showed a reduced increase in blood leucine with ingestion of fungal derived protein (mycoprotein) compared to milk protein, even though total ingested leucine was matched [ 23 ]. Despite lower leucine availability, MPS was higher with mycoprotein in both resting and exercised conditions, while mTOR phosphorylation at ser2448 was unaffected.…”

“…Plant-based proteins currently account for 30-50% of total dietary protein intake in many countries [15], with numbers exceeding 60% in less developed countries [16]. More research is emerging on 2 of 11 how plant-based proteins affect muscle health [17][18][19] and muscle remodelling, especially in combination with resistance training [20][21][22][23]. Considerable efforts have been made recently to understand how non-animal-based proteins affect the acute protein synthetic response [24][25][26][27], but studies assessing the direct effects on acute mTORC1 signalling are lacking.…”

Is There Scope for a Novel Mycelium Category of Proteins alongside Animals and Plants?

“…Mycoprotein ingestion led to slower and more sustained EAA and branched chain amino acid levels compared with milk, with evidence of a plateau at intakes of 60 to 80 g bolus of mycoprotein [ 74 ]. In addition, such high bioavailability has now been shown to stimulate muscle protein synthesis rates to a greater extent than milk protein in rested and exercised skeletal muscle of healthy young men [ 75 ].…”

“…Interestingly, further research has suggested that it is the whole-food nature of the mycelium that is important in delivering this anabolic response [ 75 ]—a feature also demonstrated for whole egg where the consumption of whole eggs promotes greater stimulation of post-exercise muscle protein synthesis than the ingestion of isonitrogenous amounts of egg whites in young men [ 76 ]. Subsequently, both the bioavailability and the amino acid composition of mycoprotein position make it a promising dietary protein source—having potential to support skeletal muscle protein metabolism [ 7 ].…”

Separating the Wheat from the Chaff: Nutritional Value of Plant Proteins and Their Potential Contribution to Human Health

“…In a recent study comparing postprandial myofibrillar protein synthesis (myoPS) in healthy older adults, 35 g of casein protein stimulated an increase in myoPS, whereas, a 35 g of wheat protein did not [ 42 ]. However, a 65 g dose of wheat protein (delivering the same amount of Leu as 35 g of casein) robustly stimulated myoPS [ 42 ], and in a separate study 32 g of fungal protein (Fusarium venenatum) stimulated postprandial myoPS to a greater extent than a Leu-matched 26 g bolus of milk protein [ 43 ].…”