Dietary supplementation with casein glycomacropeptide, leucine and tryptophan reduces plasma amino acid levels in men
Open Access
- 20 October 2021
- journal article
- research article
- Published by Cambridge University Press (CUP) in Acta Neuropsychiatrica
- Vol. 34 (2), 69-76
- https://doi.org/10.1017/neu.2021.34
Abstract
Background The treatment of mania in bipolar disorders needs to be more efficient, as the manic condition creates severe problems for the patient when it comes to work, finances, relationships, and health. This proof-of-concept study examines to what extent casein glycomacropeptide (CGMP) may reduce the precursors of dopamine, phenylalanine, and tyrosine, in plasma, and therefore be a potential new intervention to treat acute manic episodes. Method The study was designed as a double-blind randomised dose-response study of CGMP (with added leucine and tryptophan) in 15 healthy men, receiving 3 different doses of CGMP with an interval of at least 14 days. Results Administration of CGMP produced a dose dependent depletion of plasma aromatic amino acids. The total area under the curve of plasma ratios of phenylalanine-tyrosine compared to the level of leucine-isoleucine-valine-tryptophan was CGMP(20g): 3.648 [SE:0.3281]; CGMP(40g): 2.368 [SE:0.1858]; CGMP(60g)1.887 [SE:0.2591]. A comparison of the groups showed a dose dependent statistical difference, with a One-Way ANOVA summary (Dunnett) F= 11.87, p= 0.0003, CGMP 20g vs CGMP 40g, p= 0.0042, CGMP 20g vs CGMP 60g, p= 0.0002. No significant side effects were observed. Conclusions This study demonstrate CGMP is a well-tolerated and effective mixture, and that 60 g CGMP produced the highest depletion of plasma aromatic amino acids (phenylalanine and tyrosine). The effect seems to be highest after 3-4 hours. We therefore conclude that this dose should be the one considered for future studies involving CGMP in humans.Keywords
This publication has 23 references indexed in Scilit:
- Novel nutritional treatment for manic and psychotic disorders: a review of tryptophan and tyrosine depletion studies and the potential of protein-based formulations using glycomacropeptidePsychopharmacology, 2013
- Psychometric properties of a revised version of the Visual Analog Mood ScalesClinical Rehabilitation, 2012
- Influences of Exercise and Training on the Circulating Concentration of Prolactin in HumansJournal of Neuroendocrinology, 2012
- Lack of Effect of Tyrosine Depletion on Mood in Recovered Depressed WomenNeuropsychopharmacology, 2005
- Monoamine depletion in psychiatric and healthy populations: reviewMolecular Psychiatry, 2003
- Effects of a branched-chain amino acid drink in maniaThe British Journal of Psychiatry, 2003
- Antidopaminergic effects of dietary tyrosine depletion in healthy subjects and patients with manic illnessThe British Journal of Psychiatry, 2001
- Use of a dietary manipulation to deplete plasma tyrosine and phenylalanine in healthy subjectsJournal of Psychopharmacology, 1996
- The UKU side effect rating scale: A new comprehensive rating scale for psychotropic drugs and a cross‐sectional study of side effects in neuroleptic‐treated patientsActa Psychiatrica Scandinavica, 1987
- The acute effects of oral (‐)‐tryptophan in human subjects.British Journal of Clinical Pharmacology, 1975