The effect of oral essential amino acids on incretin hormone production in youth and ageing

Abdulla, H.; Bass, J.J.; Stokes, T.; Gorissen, S.H.M.; McGlory, C.; Phillips, B.E.; Phillips, S.M.; Smith, K.; Idris, I.; Atherton, P.J.

Abstract

Background
The effect of substantive doses of essential amino acids (EAA) on incretin and insulin production, and the impact of age upon this effect, is ill‐defined.

Methods
A 15‐g oral EAA drink was administered to young (N = 8; 26 ± 4.4 years) and older (N = 8; 69 ± 3.8 years) healthy volunteers. Another group of younger volunteers (N = 9; 21 ± 1.9 years) was given IV infusions to achieve equivalent plasma amino acids (AA) profiles. Plasma AA, insulin, glucagon‐like peptide‐1 (GLP‐1) and glucose‐dependent insulinotropic peptide (GIP) were quantified over 2 hours.

Results
In younger recruits, EAA‐induced rapid insulinaemia and aminoacidaemia with total amino acids(AA), EAA and branched chain amino acids (BCAA) matched between oral and IV groups. Insulin peaked at 39 ± 29 pmol L−1 at 30 minutes following oral feeding compared to 22 ± 9 pmol L−1 at 60 minutes following IV feeding (P: NS). EAA peaked at 3395 μmol L−1 at 45 minutes during IV infusion compared to 2892 μmol L−1 following oral intake (Feeding effect: P [less than] 0.0001. Oral vs IV feeding: P: NS). There was an 11% greater increase in insulin levels in the 120 minutes duration of the study in response to oral EAA as opposed to IV EAA. GIP increased following oral EAA (452 pmol L−1 vs 232 pmol L−1, P [less than] 0.05). Age did not impact insulin or incretins production.

Conclusion
Postprandial rises in EAA levels lead to rapid insulinaemia which is higher with oral compared with IV EAA, that is attributed more to GIP and unaffected by age. This finding supports EAA, on their own or as part of high‐protein meal, as nutritive therapeutics in impaired glycaemia and ageing.

Citation

Abdulla, H., Bass, J., Stokes, T., Gorissen, S., McGlory, C., Phillips, B., …Atherton, P. (2019). The effect of oral essential amino acids on incretin hormone production in youth and ageing. Endocrinology, Diabetes and Metabolism, 2(4), Article e00085. https://doi.org/10.1002/edm2.85

• Journal Article Type: Article
• Acceptance Date: Jun 15, 2019
• Online Publication Date: Jul 26, 2019
• Publication Date: 2019-10
• Deposit Date: Jul 8, 2019
• Publicly Available Date: Aug 5, 2019
• Electronic ISSN: 2398-9238
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 4
• Article Number: e00085
• DOI: https://doi.org/10.1002/edm2.85
• Keywords: Incretins, Insulin, Incretin effect, Essential amino acids, Ageing
• Public URL: https://nottingham-repository.worktribe.com/output/2285719
• Publisher URL: https://onlinelibrary.wiley.com/doi/full/10.1002/edm2.85