ArticleBehavioral and brain functions : BBF2011
Altered tryptophan and alanine transport in fibroblasts from boys with attention-deficit/hyperactivity disorder (ADHD): an in vitro study.
Article in Behavioral and brain functions : BBF, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.
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15 citing papers in PubMed, 1 synthesis or guideline pooled it, 35 citations in OpenAlex.
- Human Dermal Fibroblast: A Promising Cellular Model to Study Biological Mechanisms of Major Depression and Antidepressant Drug Response.Current neuropharmacology · 2020Pooled it
- Trial
- Exploring the Integrated Gut-Brain Metabolic Model for ADHD.Biochemical genetics · 2026Article
- Development of a novel humanized gut-brain axis model as a tool toward personalized nutrition.Communications biology · 2026Article
- Unravelling the role of alanine in mental disorders: a Mendelian randomisation study.Journal of nutritional science · 2026Article
- Association between cord blood metabolites in tryptophan pathway and childhood risk of autism spectrum disorder and attention-deficit hyperactivity disorder.Translational psychiatry · 2022Article
- Atomoxetine and circadian gene expression in human dermal fibroblasts from study participants with a diagnosis of attention-deficit hyperactivity disorder.Journal of neural transmission (Vienna, Austria : 1996) · 2021Article
- The Potential Influence of the Bacterial Microbiome on the Development and Progression of ADHD.Nutrients · 2019Review
- Impact of adult attention deficit hyperactivity disorder and medication status on sleep/wake behavior and molecular circadian rhythms.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2019Article
- Aberrant tryptophan transport in cultured fibroblast from patients with Male Idiopathic Osteoporosis: An in vitro study.Bone reports · 2018Article
- Human dermal fibroblasts in psychiatry research.Neuroscience · 2016Review
- No Tryptophan, Tyrosine and Phenylalanine Abnormalities in Children with Attention-Deficit/Hyperactivity Disorder.PloS one · 2016Article
- NET-GE: a novel NETwork-based Gene Enrichment for detecting biological processes associated to Mendelian diseases.BMC genomics · 2015Article
- Transendothelial Transport and Its Role in Therapeutics.International scholarly research notices · 2014Review
- Decreased tryptophan metabolism in patients with autism spectrum disorders.Molecular autism · 2013Article
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Authors and funding
7 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe catecholaminergic and serotonergic neurotransmitter systems are implicated in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD). The amino acid tyrosine is the precursor for synthesis of the catecholamines dopamine and norepinephrine, while tryptophan is the precursor of serotonin. A disturbed transport of tyrosine, as well as other amino acids, has been found in a number of other psychiatric disorders, such as schizophrenia, bipolar disorder and autism, when using the fibroblast cell model. Hence, the aim of this study was to explore whether children with ADHD may have disturbed amino acid transport.
methodsFibroblast cells were cultured from skin biopsies obtained from 14 boys diagnosed with ADHD and from 13 matching boys without a diagnosis of a developmental disorder. Transport of the amino acids tyrosine, tryptophan and alanine across the cell membrane was measured by the cluster tray method. The kinetic parameters, maximal transport capacity (V(max)) and affinity constant (K(m)) were determined. Any difference between the two groups was analyzed by Student's unpaired t-test or the Mann Whitney U test.
resultsThe ADHD group had significantly decreased V(max) (p = 0.039) and K(m) (increased affinity) (p = 0.010) of tryptophan transport in comparison to controls. They also had a significantly higher V(max)of alanine transport (p = 0.031), but the Km of alanine transport did not differ significantly. There were no significant differences in any of the kinetic parameters regarding tyrosine transport in fibroblasts for the ADHD group.
conclusionsTryptophan uses the same transport systems in both fibroblasts and at the blood brain barrier (BBB). Hence, a decreased transport capacity of tryptophan implies that less tryptophan is being transported across the BBB in the ADHD group. This could lead to deficient serotonin access in the brain that might cause disturbances in both the serotonergic and the catecholaminergic neurotransmitter systems, since these systems are highly interconnected. The physiological importance of an elevated transport capacity of alanine to the brain is not known to date.
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