TY - JOUR
T1 - Does supplementation with leucine-enriched protein alone and in combination with fish-oil-derived n-3 PUFA affect muscle mass, strength, physical performance, and muscle protein synthesis in well-nourished older adults? A randomized, double-blind, placebo-controlled trial
AU - Murphy, C.H.
AU - Flanagan, E.M.
AU - De Vito, G.
AU - Susta, D.
AU - Mitchelson, K.A.J.
AU - Castro, E.D.
AU - Senden, J.M.G.
AU - Goessens, J.P.B.
AU - Miklosz, A.
AU - Chabowski, A.
AU - Segurado, R.
AU - Corish, C.A.
AU - McCarthy, S.N.
AU - Egan, B.
AU - van Loon, L.J.C.
AU - Roche, H.M.
PY - 2021/6/1
Y1 - 2021/6/1
N2 - Background: Leucine-enriched protein (LEU-PRO) and long-chain (LC) n-3 (omega-3) PUFAs have each been proposed to improve muscle mass and function in older adults, whereas their combination may be more effective than either alone.Objective: The impact of LEU-PRO supplementation alone and combined with LC n-3 PUFAs on appendicular lean mass, strength, physical performance and myofibrillar protein synthesis (MyoPS) was investigated in older adults at risk of sarcopenia.Methods: This 24-wk, 3-arm parallel, randomized, double-blind, placebo-controlled trial was conducted in 107 men and women aged >= 65 y with low muscle mass and/or strength. Twice daily, participants consumed a supplement containing either LEU-PRO (3 g leucine, 10 g protein; n = 38), LEU-PRO plus LC n-3 PUFAs (0.8 g EPA, 1.1 g DHA; LEU-PRO+n-3; n = 38), or an isoenergetic control (CON; n = 31). Appendicular lean mass, handgrip strength, leg strength, physical performance, and circulating metabolic and renal function markers were measured pre, mid-, and postintervention. Integrated rates of MyoPS were assessed in a subcohort (n = 28).Results: Neither LEU-PRO nor LEU-PRO+n-3 supplementation affected appendicular lean mass, handgrip strength, knee extension strength, physical performance or MyoPS. However, isometric knee flexion peak torque (treatment effect: -7.1 Nm; 95% CI: -12.5, -1.8 Nm; P < 0.01) was lower postsupplementation in LEU-PRO+n-3 compared with CON. Serum triacylglycerol and total adiponectin concentrations were lower, and HOMA-IR was higher, in LEU-PRO+n-3 compared with CON postsupplementation (all P < 0.05). Estimated glomerular filtration rate was higher and cystatin c was lower in LEU-PRO and LEU-PRO+n-3 postsupplementation compared with CON (all P < 0.05).Conclusions: Contrary to our hypothesis, we did not observe a beneficial effect of LEU-PRO supplementation alone or combined with LC n-3 PUFA supplementation on appendicular lean mass, strength, physical performance or MyoPS in older adults at risk of sarcopenia.
AB - Background: Leucine-enriched protein (LEU-PRO) and long-chain (LC) n-3 (omega-3) PUFAs have each been proposed to improve muscle mass and function in older adults, whereas their combination may be more effective than either alone.Objective: The impact of LEU-PRO supplementation alone and combined with LC n-3 PUFAs on appendicular lean mass, strength, physical performance and myofibrillar protein synthesis (MyoPS) was investigated in older adults at risk of sarcopenia.Methods: This 24-wk, 3-arm parallel, randomized, double-blind, placebo-controlled trial was conducted in 107 men and women aged >= 65 y with low muscle mass and/or strength. Twice daily, participants consumed a supplement containing either LEU-PRO (3 g leucine, 10 g protein; n = 38), LEU-PRO plus LC n-3 PUFAs (0.8 g EPA, 1.1 g DHA; LEU-PRO+n-3; n = 38), or an isoenergetic control (CON; n = 31). Appendicular lean mass, handgrip strength, leg strength, physical performance, and circulating metabolic and renal function markers were measured pre, mid-, and postintervention. Integrated rates of MyoPS were assessed in a subcohort (n = 28).Results: Neither LEU-PRO nor LEU-PRO+n-3 supplementation affected appendicular lean mass, handgrip strength, knee extension strength, physical performance or MyoPS. However, isometric knee flexion peak torque (treatment effect: -7.1 Nm; 95% CI: -12.5, -1.8 Nm; P < 0.01) was lower postsupplementation in LEU-PRO+n-3 compared with CON. Serum triacylglycerol and total adiponectin concentrations were lower, and HOMA-IR was higher, in LEU-PRO+n-3 compared with CON postsupplementation (all P < 0.05). Estimated glomerular filtration rate was higher and cystatin c was lower in LEU-PRO and LEU-PRO+n-3 postsupplementation compared with CON (all P < 0.05).Conclusions: Contrary to our hypothesis, we did not observe a beneficial effect of LEU-PRO supplementation alone or combined with LC n-3 PUFA supplementation on appendicular lean mass, strength, physical performance or MyoPS in older adults at risk of sarcopenia.
KW - aging
KW - LC n-3 PUFA
KW - leucine
KW - protein
KW - muscle mass
KW - strength
KW - sarcopenia
KW - AMINO-ACID SUPPLEMENTATION
KW - DIETARY-FAT MODIFICATION
KW - SERUM CYSTATIN-C
KW - HEALTHY OLDER
KW - BODY-COMPOSITION
KW - VITAMIN-D
KW - RISK-FACTORS
KW - ELDERLY-PEOPLE
KW - EXERCISE
KW - AGE
U2 - 10.1093/ajcn/nqaa449
DO - 10.1093/ajcn/nqaa449
M3 - Article
C2 - 33871558
SN - 0002-9165
VL - 113
SP - 1411
EP - 1427
JO - American Journal of Clinical Nutrition
JF - American Journal of Clinical Nutrition
IS - 6
ER -