Differential effects of L-tryptophan and L-leucine administration on brain resting state functional networks and plasma hormone levels
Author(s)
Type
Journal Article
Abstract
Depending on their protein content, single meals can rapidly influence the uptake of amino acids into
the brain and thereby modify brain functions. The current study investigates the effects of two different
amino acids on the human gut-brain system, using a multimodal approach, integrating physiological
and neuroimaging data. In a randomized, placebo-controlled trial, L-tryptophan, L-leucine, glucose and
water were administered directly into the gut of 20 healthy subjects. Functional MRI (fMRI) in a resting
state paradigm (RS), combined with the assessment of insulin and glucose blood concentration, was
performed before and after treatment. Independent component analysis with dual regression technique
was applied to RS-fMRI data. Results were corrected for multiple comparisons. In comparison to glucose
and water, L-tryptophan consistently modifies the connectivity of the cingulate cortex in the default
mode network, of the insula in the saliency network and of the sensory cortex in the somatosensory
network. L-leucine has lesser effects on these functional networks. L-tryptophan and L-leucine also
modified plasma insulin concentration. Finally, significant correlations were found between brain
modifications after L-tryptophan administration and insulin plasma levels. This study shows that acute
L-tryptophan and L-leucine intake directly influence the brain networks underpinning the food-reward
system and appetite regulation.
the brain and thereby modify brain functions. The current study investigates the effects of two different
amino acids on the human gut-brain system, using a multimodal approach, integrating physiological
and neuroimaging data. In a randomized, placebo-controlled trial, L-tryptophan, L-leucine, glucose and
water were administered directly into the gut of 20 healthy subjects. Functional MRI (fMRI) in a resting
state paradigm (RS), combined with the assessment of insulin and glucose blood concentration, was
performed before and after treatment. Independent component analysis with dual regression technique
was applied to RS-fMRI data. Results were corrected for multiple comparisons. In comparison to glucose
and water, L-tryptophan consistently modifies the connectivity of the cingulate cortex in the default
mode network, of the insula in the saliency network and of the sensory cortex in the somatosensory
network. L-leucine has lesser effects on these functional networks. L-tryptophan and L-leucine also
modified plasma insulin concentration. Finally, significant correlations were found between brain
modifications after L-tryptophan administration and insulin plasma levels. This study shows that acute
L-tryptophan and L-leucine intake directly influence the brain networks underpinning the food-reward
system and appetite regulation.
Date Issued
2016-10-20
Date Acceptance
2016-10-04
Citation
Scientific Reports, 2016, 6
ISSN
2045-2322
Publisher
Nature Publishing Group
Journal / Book Title
Scientific Reports
Volume
6
Copyright Statement
© 2016 The Author(s). This work is licensed under a Creative Commons Attribution 4.0 International License. The images
or other third party material in this article are included in the article’s Creative Commons license,
unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material. To view a copy of this
license, visit http://creativecommons.org/licenses/by/4.0/
or other third party material in this article are included in the article’s Creative Commons license,
unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material. To view a copy of this
license, visit http://creativecommons.org/licenses/by/4.0/
Sponsor
ONO Pharmaceuticals Co Ltd
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000386083300001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
N/A
Subjects
Science & Technology
Multidisciplinary Sciences
Science & Technology - Other Topics
GLUCAGON-LIKE PEPTIDE-1
SUBJECT DIFFUSION DATA
AMINO-ACIDS
FOOD-INTAKE
AD-LIBITUM
INTRADUODENAL INFUSION
SPATIAL STATISTICS
VOXELWISE ANALYSIS
CONNECTIVITY MRI
HEALTHY-MEN
Publication Status
Published
Article Number
ARTN 35727