Mycoprotein ingestion within or without its wholefood matrix results in equivalent stimulation of myofibrillar protein synthesis rates in resting and exercised muscle of young men

Abstract

Ingestion of mycoprotein stimulates skeletal muscle protein synthesis (MPS) rates to a greater extent than concentrated milk protein when matched for leucine content, potentially attributable to the whole-food nature of mycoprotein. We hypothesised that bolus ingestion of mycoprotein as part of its whole food matrix would stimulate MPS rates to a greater extent compared with a leucine matched bolus of protein concentrated from mycoprotein. Twenty-four healthy young (age; 21±2 y, BMI; 24±3 kg.m2) males received primed, continuous infusions of L-[ring-2H5]phenylalanine and completed a bout of unilateral resistance leg exercise before ingesting either 70 g mycoprotein (MYC; 31.4 g protein, 2.5 g leucine; n=12) or 38.2 g of a protein concentrate obtained from mycoprotein (PCM; 28.0 g protein, 2.5 g leucine; n=12). Blood and muscle samples (vastus lateralis) were taken pre- and (4 h) post- exercise/protein ingestion to assess postabsorptive and postprandial myofibrillar protein fractional synthetic rates (FSRs) in resting and exercised muscle. Protein ingestion increased plasma essential amino acid and leucine concentrations (P<0.0001), but more rapidly (both 60 vs 90 min; P<0.0001) and to greater magnitudes (1367 vs 1346 μmol·L−1 and 298 vs 283 μmol·L−1, respectively; P<0.0001) in PCM compared with MYC. Protein ingestion increased myofibrillar FSRs (P<0.0001) in both rested (MYC, Δ0.031±0.007%·h−1 and PCM, Δ0.020±0.008%·h−1) and exercised (MYC, Δ0.057±0.011%·h−1 and PCM, Δ0.058±0.012%·h−1) muscle, with no differences between conditions (P>0.05). Mycoprotein ingestion results in equivalent postprandial stimulation of resting and post-exercise myofibrillar protein synthesis rates irrespective of whether it is consumed within or without its whole-food matrix.

Ingestion of a variety of non-animal-derived dietary protein sources results in diverse postprandial plasma amino acid responses which differ between young and older adults

“…protein content > 80 % of total mass). This likely explains the observed rapid increase in postprandial circulating insulin and amino acid concentrations, a finding consistent with recent studies (26,27) , and suggests pea protein to be an ideal source for stimulating tissue anabolism. In contrast, the aminoacidaemic response to lupin ingestion may have been delayed, or impaired, due to the high fibre content within its whole-food matrix (Table 3), which has been proposed to modulate the rise in postprandial amino acid concentrations (29,30) .…”

“…Our data demonstrate low postprandial methionine availabilities following ingestion of both pea and lupin, an observation also observed previously (25,63) . This is of relevance since single in vivo amino acid deficiencies are proposed to provide substrate limitation to the continuation of postprandial MPS rates (64) , though we did not observe this in a recent study (27) .…”

“…On the other hand, despite being low in methionine, pea protein is high in other EAA and leucine (17) . Recent work reported equivalent in vivo ileal digestibility following pea and casein protein ingestion (26) and robust post-exercise muscle protein synthetic responses following pea protein ingestion (27) . Aside from animal- and plant-derived proteins, other categories of proteins are generating scientific and commercial interest (17,28) .…”

Association of postprandial postexercise muscle protein synthesis rates with dietary leucine: A systematic review

“…However, once other variables are introduced, such as comparing different protein sources (Chan et al, 2019; Churchward‐Venne, Breen, et al, 2014; Dideriksen et al, 2011; Reidy et al, 2013), isolated vs whole foods (Burd et al, 2015; Mitchell, McGregor, et al, 2015; Van Vliet et al, 2017), meal ingestion (Kim et al, 2016; Symons et al, 2011) or co‐ingestion with other macronutrients (Gorissen et al, 2014; Hamer et al, 2013; Koopman et al, 2007; Staples et al, 2011), the relationship is far less clear. We (Monteyne, Coelho, Porter, Abdelrahman, Jameson, Finnigan, et al, 2020; Monteyne, Coelho, Porter, Abdelrahman, Jameson, Jackman, et al, 2020; West et al, 2022) and others (Burd et al, 2015; Chan et al, 2019; Van Vliet et al, 2017) have observed a dissociation between circulating leucine concentrations and MPS in a series of recent studies, specifically involving whole food approaches. For example, a 25% greater MPS response was observed with ingestion of skim milk vs. beef despite a significantly lower plasma leucine concentration (Burd et al, 2015).…”

Food for our future: the nutritional science behind the sustainable fungal protein – mycoprotein. A symposium review

“…Recent research has studied whether bolus ingestion of mycoprotein (as part of its wholefood matrix) would stimulate MPS rates more than a leucine-matched bolus of protein concentrated from mycoprotein. It has been shown that protein consumption significantly raised plasma essential amino acid and leucine concentrations ( P < 0⋅0001), but more rapidly and to greater magnitudes when derived from the milk protein concentrate ( 26 ) . MPS synthesis, however, increased in rested and exercised muscle in both conditions indicating that the ‘form’ of delivery was irrespective.…”