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Yates JR. Aberrant glutamatergic systems underlying impulsive behaviors: Insights from clinical and preclinical research. Prog Neuropsychopharmacol Biol Psychiatry 2024; 135:111107. [PMID: 39098647 DOI: 10.1016/j.pnpbp.2024.111107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 07/07/2024] [Accepted: 07/24/2024] [Indexed: 08/06/2024]
Abstract
Impulsivity is a broad construct that often refers to one of several distinct behaviors and can be measured with self-report questionnaires and behavioral paradigms. Several psychiatric conditions are characterized by one or more forms of impulsive behavior, most notably the impulsive/hyperactive subtype of attention-deficit/hyperactivity disorder (ADHD), mood disorders, and substance use disorders. Monoaminergic neurotransmitters are known to mediate impulsive behaviors and are implicated in various psychiatric conditions. However, growing evidence suggests that glutamate, the major excitatory neurotransmitter of the mammalian brain, regulates important functions that become dysregulated in conditions like ADHD. The purpose of the current review is to discuss clinical and preclinical evidence linking glutamate to separate aspects of impulsivity, specifically motor impulsivity, impulsive choice, and affective impulsivity. Hyperactive glutamatergic activity in the corticostriatal and the cerebro-cerebellar pathways are major determinants of motor impulsivity. Conversely, hypoactive glutamatergic activity in frontal cortical areas and hippocampus and hyperactive glutamatergic activity in anterior cingulate cortex and nucleus accumbens mediate impulsive choice. Affective impulsivity is controlled by similar glutamatergic dysfunction observed for motor impulsivity, except a hyperactive limbic system is also involved. Loss of glutamate homeostasis in prefrontal and nucleus accumbens may contribute to motor impulsivity/affective impulsivity and impulsive choice, respectively. These results are important as they can lead to novel treatments for those with a condition characterized by increased impulsivity that are resistant to conventional treatments.
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Affiliation(s)
- Justin R Yates
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY 41099, USA.
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2
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Chatterjee M, Saha S, Shom S, Dutta N, Sinha S, Mukhopadhyay K. Glutamate receptor genetic variants affected peripheral glutamatergic transmission and treatment induced improvement of Indian ADHD probands. Sci Rep 2023; 13:19922. [PMID: 37964012 PMCID: PMC10645851 DOI: 10.1038/s41598-023-47117-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 11/09/2023] [Indexed: 11/16/2023] Open
Abstract
Attention deficit hyperactivity disorder (ADHD), a childhood-onset neurobehavioral disorder, often perturbs scholastic achievement and peer-relationship. The pivotal role of glutamate (Glu) in learning and memory indicated an influence of Glu in ADHD, leading to the exploration of Glu in different brain regions of ADHD subjects. We for the first time analyzed GluR genetic variations, Glu levels, as well as expression of Glu receptors (GluR) in the peripheral blood of eastern Indian ADHD probands to find out the relevance of Glu in ADHD prognosis. After obtaining informed written consent for participation, peripheral blood was collected for analyzing the genetic variants, Glu level, and expression of target genes. Since ADHD probands are often treated with methylphenidate or atomoxetine for providing symptomatic remediation, we have also tested post-therapeutic improvement in the ADHD trait scores in the presence of different GluR genotypes. Two variants, GRM7 rs3749380 "T" and GRIA1 rs2195450 "C", exhibited associations with ADHD (P ≤ 0.05). A few GluR genetic variants showed significant association with higher trait severity, low IQ, lower plasma Glu level, down-regulated GluR mRNA expression, and poor response to medications. This indicates that down-regulated glutamatergic system may have an effect on ADHD etiology and treatment efficacy warranting further in-depth investigation.
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Affiliation(s)
- Mahasweta Chatterjee
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal, 700107, India
| | - Sharmistha Saha
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal, 700107, India
| | - Sayanti Shom
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal, 700107, India
| | - Nilanjana Dutta
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal, 700107, India
| | - Swagata Sinha
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal, 700107, India
| | - Kanchan Mukhopadhyay
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal, 700107, India.
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Sun Y, Zhang M, Saggar M. Cross-attractor modeling of resting-state functional connectivity in psychiatric disorders. Neuroimage 2023; 279:120302. [PMID: 37579998 PMCID: PMC10515743 DOI: 10.1016/j.neuroimage.2023.120302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 07/26/2023] [Accepted: 07/29/2023] [Indexed: 08/16/2023] Open
Abstract
Resting-state functional connectivity (RSFC) is altered across various psychiatric disorders. Brain network modeling (BNM) has the potential to reveal the neurobiological underpinnings of such abnormalities by dynamically modeling the structure-function relationship and examining biologically relevant parameters after fitting the models with real data. Although innovative BNM approaches have been developed, two main issues need to be further addressed. First, previous BNM approaches are primarily limited to simulating noise-driven dynamics near a chosen attractor (or a stable brain state). An alternative approach is to examine multi(or cross)-attractor dynamics, which can be used to better capture non-stationarity and switching between states in the resting brain. Second, previous BNM work is limited to characterizing one disorder at a time. Given the large degree of co-morbidity across psychiatric disorders, comparing BNMs across disorders might provide a novel avenue to generate insights regarding the dynamical features that are common across (vs. specific to) disorders. Here, we address these issues by (1) examining the layout of the attractor repertoire over the entire multi-attractor landscape using a recently developed cross-attractor BNM approach; and (2) characterizing and comparing multiple disorders (schizophrenia, bipolar, and ADHD) with healthy controls using an openly available and moderately large multimodal dataset from the UCLA Consortium for Neuropsychiatric Phenomics. Both global and local differences were observed across disorders. Specifically, the global coupling between regions was significantly decreased in schizophrenia patients relative to healthy controls. At the same time, the ratio between local excitation and inhibition was significantly higher in the schizophrenia group than the ADHD group. In line with these results, the schizophrenia group had the lowest switching costs (energy gaps) across groups for several networks including the default mode network. Paired comparison also showed that schizophrenia patients had significantly lower energy gaps than healthy controls for the somatomotor and visual networks. Overall, this study provides preliminary evidence supporting transdiagnostic multi-attractor BNM approaches to better understand psychiatric disorders' pathophysiology.
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Affiliation(s)
- Yinming Sun
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94304, USA
| | - Mengsen Zhang
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Manish Saggar
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94304, USA.
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Bakhshi S, Tehrani-Doost M, Batouli SAH. Evaluation of fronto-cerebellar neurometabolites in youth with ADHD compared to the healthy group and their associations with cognitive and behavioral characteristics: A proton magnetic spectroscopy study. Int J Psychophysiol 2022; 182:190-199. [DOI: 10.1016/j.ijpsycho.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022]
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Emerging findings of glutamate-glutamine imbalance in the medial prefrontal cortex in attention deficit/hyperactivity disorder: systematic review and meta-analysis of spectroscopy studies. Eur Arch Psychiatry Clin Neurosci 2022; 272:1395-1411. [PMID: 35322293 DOI: 10.1007/s00406-022-01397-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 03/01/2022] [Indexed: 12/11/2022]
Abstract
One of the main challenges in investigating the neurobiology of ADHD is our limited capacity to study its neurochemistry in vivo. Magnetic resonance spectroscopy (MRS) estimates metabolite concentrations within the brain, but approaches and findings have been heterogeneous. To assess differences in brain metabolites between patients with ADHD and healthy controls, we searched 12 databases screening for MRS studies. Studies were divided into 'children and adolescents' and 'adults' and meta-analyses were performed for each brain region with more than five studies. The quality of studies was assessed by the Newcastle-Ottawa Scale. Thirty-three studies met our eligibility criteria, including 874 patients with ADHD. Primary analyses revealed that the right medial frontal area of children with ADHD presented higher concentrations of a composite of glutamate and glutamine (p = 0.02, SMD = 0.53). Glutamate might be implicated in pruning and neurodegenerative processes as an excitotoxin, while glutamine excess might signal a glutamate depletion that could hinder neurotrophic activity. Both neuro metabolites could be implicated in the differential cortical thinning observed in patients with ADHD across all ages. Notably, more homogeneous designs and reporting guidelines are the key factors to determine how suitable MRS is for research and, perhaps, for clinical psychiatry. Results of this meta-analysis provided an overall map of the brain regions evaluated so far, addressed the role of glutamatergic metabolites in the pathophysiology of ADHD, and pointed to new perspectives for consistent use of the tool in the field.
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Lee IO, Skuse DH, Constable PA, Marmolejo-Ramos F, Olsen LR, Thompson DA. The electroretinogram b-wave amplitude: a differential physiological measure for Attention Deficit Hyperactivity Disorder and Autism Spectrum Disorder. J Neurodev Disord 2022; 14:30. [PMID: 35524181 PMCID: PMC9077889 DOI: 10.1186/s11689-022-09440-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/12/2022] [Indexed: 12/02/2022] Open
Abstract
Background Attention Deficit Hyperactivity Disorder (ADHD) is the most prevalent childhood neurodevelopmental disorder. It shares some genetic risk with Autism Spectrum Disorder (ASD), and the conditions often occur together. Both are potentially associated with abnormal glutamate and GABA neurotransmission, which can be modelled by measuring the synaptic activity in the retina with an electroretinogram (ERG). Reduction of retinal responses in ASD has been reported, but little is known about retinal activity in ADHD. In this study, we compared the light-adapted ERGs of individuals with ADHD, ASD and controls to investigate whether retinal responses differ between these neurodevelopmental conditions. Methods Full field light-adapted ERGs were recorded from 15 ADHD, 57 ASD (without ADHD) and 59 control participants, aged from 5.4 to 27.3 years old. A Troland protocol was used with a random series of nine flash strengths from −0.367 to 1.204 log photopic cd.s.m−2. The time-to-peak and amplitude of the a- and b-waves and the parameters of the Photopic Negative Response (PhNR) were compared amongst the three groups of participants, using generalised estimating equations. Results Statistically significant elevations of the ERG b-wave amplitudes, PhNR responses and faster timings of the b-wave time-to-peak were found in those with ADHD compared with both the control and ASD groups. The greatest elevation in the b-wave amplitudes associated with ADHD were observed at 1.204 log phot cd.s.m−2 flash strength (p < .0001), at which the b-wave amplitude in ASD was significantly lower than that in the controls. Using this measure, ADHD could be distinguished from ASD with an area under the curve of 0.88. Conclusions The ERG b-wave amplitude appears to be a distinctive differential feature for both ADHD and ASD, which produced a reversed pattern of b-wave responses. These findings imply imbalances between glutamate and GABA neurotransmission which primarily regulate the b-wave formation. Abnormalities in the b-wave amplitude could provisionally serve as a biomarker for both neurodevelopmental conditions. Supplementary Information The online version contains supplementary material available at 10.1186/s11689-022-09440-2.
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Affiliation(s)
- Irene O Lee
- Behavioural and Brain Sciences Unit, Population Policy and Practice Programme, UCL Great Ormond Street Institute of Child Health, University College London, London, UK.
| | - David H Skuse
- Behavioural and Brain Sciences Unit, Population Policy and Practice Programme, UCL Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Paul A Constable
- Caring Futures Institute, College of Nursing and Health Sciences, Flinders University, Adelaide, South Australia, Australia
| | - Fernando Marmolejo-Ramos
- Centre for Change and Complexity in Learning, University of South Australia, Adelaide, Australia
| | - Ludvig R Olsen
- Department of Molecular Medicine (MOMA), Aarhus University, Aarhus, Denmark
| | - Dorothy A Thompson
- The Tony Kriss Visual Electrophysiology Unit, Clinical and Academic Department of Ophthalmology, Sight and Sound Centre, Great Ormond Street Hospital for Children NHS Trust, London, UK.,UCL Great Ormond Street Institute of Child Health, University College London, London, UK
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Mamiya PC, Richards TL, Edden RAE, Lee AKC, Stein MA, Kuhl PK. Reduced Glx and GABA Inductions in the Anterior Cingulate Cortex and Caudate Nucleus Are Related to Impaired Control of Attention in Attention-Deficit/Hyperactivity Disorder. Int J Mol Sci 2022; 23:ijms23094677. [PMID: 35563067 PMCID: PMC9100027 DOI: 10.3390/ijms23094677] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/17/2022] [Accepted: 04/20/2022] [Indexed: 11/16/2022] Open
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that impairs the control of attention and behavioral inhibition in affected individuals. Recent genome-wide association findings have revealed an association between glutamate and GABA gene sets and ADHD symptoms. Consistently, people with ADHD show altered glutamate and GABA content in the brain circuitry that is important for attention control function. Yet, it remains unknown how glutamate and GABA content in the attention control circuitry change when people are controlling their attention, and whether these changes can predict impaired attention control in people with ADHD. To study these questions, we recruited 18 adults with ADHD (31-51 years) and 16 adults without ADHD (28-54 years). We studied glutamate + glutamine (Glx) and GABA content in the fronto-striatal circuitry while participants performed attention control tasks. We found that Glx and GABA concentrations at rest did not differ between participants with ADHD or without ADHD. However, while participants were performing the attention control tasks, participants with ADHD showed smaller Glx and GABA increases than participants without ADHD. Notably, smaller GABA increases in participants with ADHD significantly predicted their poor task performance. Together, these findings provide the first demonstration showing that attention control deficits in people with ADHD may be related to insufficient responses of the GABAergic system in the fronto-striatal circuitry.
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Affiliation(s)
- Ping C. Mamiya
- Institute for Learning & Brain Sciences, University of Washington, Seattle, WA 98195, USA;
- Correspondence:
| | - Todd L. Richards
- Department of Radiology, University of Washington, Seattle, WA 98195, USA;
| | - Richard A. E. Edden
- Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21205, USA;
| | - Adrian K. C. Lee
- Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98195, USA;
| | - Mark A. Stein
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA;
| | - Patricia K. Kuhl
- Institute for Learning & Brain Sciences, University of Washington, Seattle, WA 98195, USA;
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Dominguez S, Lencinas I, Bartos M, Gallegos C, Bras C, Mónaco N, Minetti A, Gumilar F. Neurobehavioral and neurochemical effects in rats offspring co-exposed to arsenic and fluoride during development. Neurotoxicology 2021; 84:30-40. [PMID: 33609566 DOI: 10.1016/j.neuro.2021.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/11/2021] [Accepted: 02/14/2021] [Indexed: 11/29/2022]
Abstract
Arsenic (iAs) and fluoride (F) are ubiquitous in the environment. All over the world, in many countries, thousands of people are suffering from the toxic effects of arsenicals ad fluorides. These two elements are recognized worldwide as the most serious inorganic contaminants in drinking water. When two different types of toxicants are simultaneously going inside the human body they may function independently or can act as synergistic or antagonistic to one another. Although there have been reports in literature of individual toxicity of iAs and F, however, not much is known about the effects following the combined exposure to the toxicants above mentioned. In this work, we investigated the effect of the co-exposure to low levels of iAs/F through drinking water during pregnancy and lactation on central nervous system functionality in the exposed rats offspring. Wistar rats were exposed to one of these solutions: 0.05 mg/L iAs and 5 mg/L F (Concentration A) or 0.10 mg/L iAs and 10 mg/L F (Concentration B) from gestational day 0 up to post-gestational day 21. Sensory-motor reflexes a Functional Observational Battery and the locomotor activity in an open field were assessed in offspring. Additionally, the transaminases, acethylcholinesterase and catalase levels in the striatum were determined to elucidate the possible molecular mechanisms involved in locomotor and neurobehavioral disorders. The results showed that iAs/F exposition during development produces a delay reach the maturity of sensorimotor reflexes. A decrease in the nociceptive reflex response, and increase in the locomotor activity in adult rats offspring were observed. The increase in oxidative stress, the inhibition of transaminases enzymes and the inhibition of AChE in the striatum may partially regulate all the neurobehavioral disorders observed.
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Affiliation(s)
- Sergio Dominguez
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Ileana Lencinas
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Mariana Bartos
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Cristina Gallegos
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Cristina Bras
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Nina Mónaco
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Alejandra Minetti
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Fernanda Gumilar
- Laboratorio de Toxicología, Instituto de Investigaciones Biológicas y Biomédicas del Sur (INBIOSUR), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Depto. de Biología, Bioquímica y Farmacia, San Juan 670, 8000, Bahía Blanca, Argentina.
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Mamiya PC, Arnett AB, Stein MA. Precision Medicine Care in ADHD: The Case for Neural Excitation and Inhibition. Brain Sci 2021; 11:brainsci11010091. [PMID: 33450814 PMCID: PMC7828220 DOI: 10.3390/brainsci11010091] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/15/2020] [Accepted: 01/11/2021] [Indexed: 12/14/2022] Open
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that has become increasingly prevalent worldwide. Its core symptoms, including difficulties regulating attention, activity level, and impulses, appear in early childhood and can persist throughout the lifespan. Current pharmacological options targeting catecholamine neurotransmissions have effectively alleviated symptoms in some, but not all affected individuals, leaving clinicians to implement trial-and-error approach to treatment. In this review, we discuss recent experimental evidence from both preclinical and human studies that suggest imbalance of excitation/inhibition (E/I) in the fronto-striatal circuitry during early development may lead to enduring neuroanatomical abnormality of the circuitry, causing persistence of ADHD symptoms in adulthood. We propose a model of precision medicine care that includes E/I balance as a candidate biomarker for ADHD, development of GABA-modulating medications, and use of magnetic resonance spectroscopy and scalp electrophysiology methods to monitor the effects of treatments on shifting E/I balance throughout the lifespan.
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Affiliation(s)
- Ping C. Mamiya
- Institute for Learning and Brain Sciences, University of Washington, Seattle, WA 98195, USA
- Correspondence:
| | - Anne B. Arnett
- Department of Psychiatry & Behavioral Sciences, University of Washington, Seattle, WA 98195, USA; (A.B.A.); (M.A.S.)
| | - Mark A. Stein
- Department of Psychiatry & Behavioral Sciences, University of Washington, Seattle, WA 98195, USA; (A.B.A.); (M.A.S.)
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Altered brain metabolism contributes to executive function deficits in school-aged children born very preterm. Pediatr Res 2020; 88:739-748. [PMID: 32590836 PMCID: PMC7577839 DOI: 10.1038/s41390-020-1024-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/26/2020] [Accepted: 05/27/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Executive function deficits in children born very preterm (VPT) have been linked to anatomical abnormalities in white matter and subcortical brain structures. This study aimed to investigate how altered brain metabolism contributes to these deficits in VPT children at school-age. METHODS Fifty-four VPT participants aged 8-13 years and 62 term-born peers were assessed with an executive function test battery. Brain metabolites were obtained in the frontal white matter and the basal ganglia/thalami, using proton magnetic resonance spectroscopy (MRS). N-acetylaspartate (NAA)/creatine (Cr), choline (Cho)/Cr, glutamate + glutamine (Glx)/Cr, and myo-Inositol (mI)/Cr were compared between groups and associations with executive functions were explored using linear regression. RESULTS In the frontal white matter, VPT showed lower Glx/Cr (mean difference: -5.91%, 95% CI [-10.50, -1.32]), higher Cho/Cr (7.39%, 95%-CI [2.68, 12.10]), and higher mI/Cr (5.41%, 95%-CI [0.18, 10.64]) while there were no differences in the basal ganglia/thalami. Lower executive functions were associated with lower frontal Glx/Cr ratios in both groups (β = 0.16, p = 0.05) and higher mI/Cr ratios in the VPT group only (interaction: β = -0.17, p = 0.02). CONCLUSION Long-term brain metabolite alterations in the frontal white matter may be related to executive function deficits in VPT children at school-age. IMPACT Very preterm birth is associated with long-term brain metabolite alterations in the frontal white matter. Such alterations may contribute to deficits in executive function abilities. Injury processes in the brain can persist for years after the initial insult. Our findings provide new insights beyond structural and functional imaging, which help to elucidate the processes involved in abnormal brain development following preterm birth. Ultimately, this may lead to earlier identification of children at risk for developing deficits and more effective interventions.
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Dunn GA, Nigg JT, Sullivan EL. Neuroinflammation as a risk factor for attention deficit hyperactivity disorder. Pharmacol Biochem Behav 2019; 182:22-34. [PMID: 31103523 PMCID: PMC6855401 DOI: 10.1016/j.pbb.2019.05.005] [Citation(s) in RCA: 138] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 05/08/2019] [Accepted: 05/14/2019] [Indexed: 01/08/2023]
Abstract
Attention Deficit Hyperactivity Disorder (ADHD) is a persistent, and impairing pediatric-onset neurodevelopmental condition. Its high prevalence, and recurrent controversy over its widespread identification and treatment, drive strong interest in its etiology and mechanisms. Emerging evidence for a role for neuroinflammation in ADHD pathophysiology is of great interest. This evidence includes 1) the above-chance comorbidity of ADHD with inflammatory and autoimmune disorders, 2) initial studies indicating an association with ADHD and increased serum cytokines, 3) preliminary evidence from genetic studies demonstrating associations between polymorphisms in genes associated with inflammatory pathways and ADHD, 4) emerging evidence that early life exposure to environmental factors may increase risk for ADHD via an inflammatory mechanism, and 5) mechanistic evidence from animal models of maternal immune activation documenting behavioral and neural outcomes consistent with ADHD. Prenatal exposure to inflammation is associated with changes in offspring brain development including reductions in cortical gray matter volume and the volume of certain cortical areas -parallel to observations associated with ADHD. Alterations in neurotransmitter systems, including the dopaminergic, serotonergic and glutamatergic systems, are observed in ADHD populations. Animal models provide strong evidence that development and function of these neurotransmitters systems are sensitive to exposure to in utero inflammation. In summary, accumulating evidence from human studies and animal models, while still incomplete, support a potential role for neuroinflammation in the pathophysiology of ADHD. Confirmation of this association and the underlying mechanisms have become valuable targets for research. If confirmed, such a picture may be important in opening new intervention routes.
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Affiliation(s)
| | - Joel T Nigg
- Oregon Health and Science University, United States of America
| | - Elinor L Sullivan
- University of Oregon, United States of America; Oregon Health and Science University, United States of America; Oregon National Primate Research Center, United States of America.
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12
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Huang X, Wang M, Zhang Q, Chen X, Wu J. The role of glutamate receptors in attention-deficit/hyperactivity disorder: From physiology to disease. Am J Med Genet B Neuropsychiatr Genet 2019; 180:272-286. [PMID: 30953404 DOI: 10.1002/ajmg.b.32726] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/12/2019] [Accepted: 03/19/2019] [Indexed: 12/15/2022]
Abstract
Attention-deficit hyperactivity disorder (ADHD) is the most common psychiatric disorder in children and adolescents, which is characterized by behavioral problems such as attention deficit, hyperactivity, and impulsivity. As the receptors of the major excitatory neurotransmitter in the mammalian central nervous system (CNS), glutamate receptors (GluRs) are strongly linked to normal brain functioning and pathological processes. Extensive investigations have been made about the structure, function, and regulation of GluR family, describing evidences that support the disruption of these mechanisms in mental disorders, including ADHD. In this review, we briefly described the family and function of GluRs in the CNS, and discussed what is recently known about the role of GluRs in ADHD, that including GluR genes, animal models, and the treatment, which would help us further elucidate the etiology of ADHD.
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Affiliation(s)
- Xin Huang
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Min Wang
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Zhang
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xinzhen Chen
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing Wu
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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13
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Bauer J, Werner A, Kohl W, Kugel H, Shushakova A, Pedersen A, Ohrmann P. Hyperactivity and impulsivity in adult attention-deficit/hyperactivity disorder is related to glutamatergic dysfunction in the anterior cingulate cortex. World J Biol Psychiatry 2018; 19:538-546. [PMID: 27973969 DOI: 10.1080/15622975.2016.1262060] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVES Attention-deficit/hyperactivity disorder (ADHD) is closely linked to the dysregulation of dopaminergic and noradrenergic neurotransmission in the fronto-striatal neural network, including the anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC). Additionally, increasing evidence supports the involvement of the glutamatergic system in the pathophysiology of ADHD. Impulsivity, a core symptom in patients with ADHD, has been repeatedly associated with glutamatergic neurotransmission, and pharmacological treatment of ADHD has been shown to reduce glutamate levels in the prefrontal cortex. METHODS We investigated glutamate levels in the ACC and the DLPFC in 30 adults with ADHD and 30 healthy controls using single-voxel proton magnetic resonance spectroscopy on a 3T scanner. RESULTS The ADHD group showed a significant increase in glutamate in the ACC compared to controls, no significant differences in metabolites were observed in the DLPFC. Overall, glutamate levels in the ACC were positively correlated with ADHD symptomatology, especially hyperactivity and impulsivity symptoms. CONCLUSIONS Increased levels of glutamate in the ACC, which were positively correlated with hyperactivity and impulsivity, support the hypothesis that dysfunctional glutamatergic neurotransmission is at least partially responsible for ADHD symptomatology. Modulation of glutamatergic neurotransmission might therefore be a promising avenue for future pharmacological interventions.
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Affiliation(s)
- Jochen Bauer
- a Institute for Clinical Radiology, School of Medicine , University of Muenster , Germany
| | - Anne Werner
- b Department of Psychiatry, School of Medicine , University of Muenster , Germany
| | - Waldemar Kohl
- b Department of Psychiatry, School of Medicine , University of Muenster , Germany
| | - Harald Kugel
- a Institute for Clinical Radiology, School of Medicine , University of Muenster , Germany
| | - Anna Shushakova
- c Clinical Psychology and Psychotherapy, Institute of Psychology , University of Kiel , Germany
| | - Anya Pedersen
- c Clinical Psychology and Psychotherapy, Institute of Psychology , University of Kiel , Germany
| | - Patricia Ohrmann
- b Department of Psychiatry, School of Medicine , University of Muenster , Germany
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14
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Moretto E, Murru L, Martano G, Sassone J, Passafaro M. Glutamatergic synapses in neurodevelopmental disorders. Prog Neuropsychopharmacol Biol Psychiatry 2018; 84:328-342. [PMID: 28935587 DOI: 10.1016/j.pnpbp.2017.09.014] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/28/2017] [Accepted: 09/16/2017] [Indexed: 12/22/2022]
Abstract
Neurodevelopmental disorders (NDDs) are a group of diseases whose symptoms arise during childhood or adolescence and that impact several higher cognitive functions such as learning, sociability and mood. Accruing evidence suggests that a shared pathogenic mechanism underlying these diseases is the dysfunction of glutamatergic synapses. We summarize present knowledge on autism spectrum disorders (ASD), intellectual disability (ID), Down syndrome (DS), Rett syndrome (RS) and attention-deficit hyperactivity disorder (ADHD), highlighting the involvement of glutamatergic synapses and receptors in these disorders. The most commonly shared defects involve α-amino-3-hydroxy-5-methyl- 4-isoxazole propionic acid receptors (AMPARs), N-methyl-d-aspartate receptors (NMDARs) and metabotropic glutamate receptors (mGluRs), whose functions are strongly linked to synaptic plasticity, affecting both cell-autonomous features as well as circuit formation. Moreover, the major scaffolding proteins and, thus, the general structure of the synapse are often deregulated in neurodevelopmental disorders, which is not surprising considering their crucial role in the regulation of glutamate receptor positioning and functioning. This convergence of defects supports the definition of neurodevelopmental disorders as a continuum of pathological manifestations, suggesting that glutamatergic synapses could be a therapeutic target to ameliorate patient symptomatology.
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Affiliation(s)
- Edoardo Moretto
- CNR, Institute of Neuroscience, Via Vanvitelli 32, 20129 Milan, Italy
| | - Luca Murru
- CNR, Institute of Neuroscience, Via Vanvitelli 32, 20129 Milan, Italy
| | - Giuseppe Martano
- CNR, Institute of Neuroscience, Via Vanvitelli 32, 20129 Milan, Italy
| | - Jenny Sassone
- San Raffaele Scientific Institute, Vita-Salute University, Milan, Italy
| | - Maria Passafaro
- CNR, Institute of Neuroscience, Via Vanvitelli 32, 20129 Milan, Italy.
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15
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Ghajar A, Aghajan-Nashtaei F, Afarideh M, Mohammadi MR, Akhondzadeh S. l-Carnosine as Adjunctive Therapy in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. J Child Adolesc Psychopharmacol 2018; 28:331-338. [PMID: 29469593 DOI: 10.1089/cap.2017.0157] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVES This study aimed to investigate the efficacy and tolerability of l-carnosine as an add-on to methylphenidate in management of children with attention-deficit/hyperactivity disorder (ADHD). METHODS This was an 8-week, randomized, double-blind placebo-controlled study. Fifty-six drug-free children and adolescents aged 6-17 years old with a diagnosis of ADHD entered the study. The patients were randomly assigned to l-carnosine (800 mg/d in two divided doses) or placebo plus methylphenidate (0.5-1.5 mg/kg/d) for 8 weeks. Children were assessed using the Teacher and Parent ADHD Rating Scale-IV (ADHD-RS-IV) at baseline and at weeks 4 and 8 postbaseline. RESULTS Fifty patients completed the study, and all had two postbaseline measurements. Using the general linear model repeated measures, significant effect was observed for time × treatment interaction on total and inattention subscales of the Parent ADHD-RS (Greenhouse-Geisser corrected: F = 3.783, df = 1.444, p = 0.041 and F = 4.032, df = 1.600, p = 0.030). Improvements in the Teacher ADHD-RS were not significantly different between the two groups in total (Greenhouse-Geisser corrected: F = 0.200, df = 1.218, p = 0.705), as well as inattention and hyperactivity subscale scores (p = 0.956 and 0.281, respectively). The frequency of side effects was not significantly different between the two treatment arms. CONCLUSIONS l-carnosine, as a supplementary medication, might be beneficial in treatment of children with ADHD. However, further investigations and different doses of l-carnosine are required to replicate these findings in children with ADHD.
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Affiliation(s)
- Alireza Ghajar
- Psychiatric Research Center, Roozbeh Hospital, Tehran University of Medical Sciences , Tehran, Iran
| | - Farinaz Aghajan-Nashtaei
- Psychiatric Research Center, Roozbeh Hospital, Tehran University of Medical Sciences , Tehran, Iran
| | - Mohsen Afarideh
- Psychiatric Research Center, Roozbeh Hospital, Tehran University of Medical Sciences , Tehran, Iran
| | - Mohammad-Reza Mohammadi
- Psychiatric Research Center, Roozbeh Hospital, Tehran University of Medical Sciences , Tehran, Iran
| | - Shahin Akhondzadeh
- Psychiatric Research Center, Roozbeh Hospital, Tehran University of Medical Sciences , Tehran, Iran
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16
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Marquardt L, Eichele H, Lundervold AJ, Haavik J, Eichele T. Event-Related-Potential (ERP) Correlates of Performance Monitoring in Adults With Attention-Deficit Hyperactivity Disorder (ADHD). Front Psychol 2018; 9:485. [PMID: 29706908 PMCID: PMC5907771 DOI: 10.3389/fpsyg.2018.00485] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 03/22/2018] [Indexed: 12/21/2022] Open
Abstract
Introduction: Attention-deficit hyperactivity disorder (ADHD) is one of the most frequent neurodevelopmental disorders in children and tends to persist into adulthood. Evidence from neuropsychological, neuroimaging, and electrophysiological studies indicates that alterations of error processing are core symptoms in children and adolescents with ADHD. To test whether adults with ADHD show persisting deficits and compensatory processes, we investigated performance monitoring during stimulus-evaluation and response-selection, with a focus on errors, as well as within-group correlations with symptom scores. Methods: Fifty-five participants (27 ADHD and 28 controls) aged 19-55 years performed a modified flanker task during EEG recording with 64 electrodes, and the ADHD and control groups were compared on measures of behavioral task performance, event-related potentials of performance monitoring (N2, P3), and error processing (ERN, Pe). Adult ADHD Self-Report Scale (ASRS) was used to assess ADHD symptom load. Results: Adults with ADHD showed higher error rates in incompatible trials, and these error rates correlated positively with the ASRS scores. Also, we observed lower P3 amplitudes in incompatible trials, which were inversely correlated with symptom load in the ADHD group. Adults with ADHD also displayed reduced error-related ERN and Pe amplitudes. There were no significant differences in reaction time (RT) and RT variability between the two groups. Conclusion: Our findings show deviations of electrophysiological measures, suggesting reduced effortful engagement of attentional and error-monitoring processes in adults with ADHD. Associations between ADHD symptom scores, event-related potential amplitudes, and poorer task performance in the ADHD group further support this notion.
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Affiliation(s)
- Lynn Marquardt
- K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, Department of Biomedicine, University of Bergen, Bergen, Norway.,Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Heike Eichele
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Astri J Lundervold
- K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, Department of Biomedicine, University of Bergen, Bergen, Norway.,Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Jan Haavik
- K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, Department of Biomedicine, University of Bergen, Bergen, Norway.,Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
| | - Tom Eichele
- K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, Department of Biomedicine, University of Bergen, Bergen, Norway.,Section for Neurophysiology, Department of Neurology, Haukeland University Hospital, Bergen, Norway
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17
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Naaijen J, Lythgoe DJ, Zwiers MP, Hartman CA, Hoekstra PJ, Buitelaar JK, Aarts E. Anterior cingulate cortex glutamate and its association with striatal functioning during cognitive control. Eur Neuropsychopharmacol 2018; 28:381-391. [PMID: 29395624 DOI: 10.1016/j.euroneuro.2018.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 01/12/2018] [Accepted: 01/16/2018] [Indexed: 02/02/2023]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by structural, functional and neurochemical alterations of the fronto-striatal circuits and by deficits in cognitive control. In particular, ADHD has been associated with impairments in top-down fronto-striatal glutamate-signalling. However, it is unknown whether fronto-striatal glutamate is related to cognitive control dysfunction. Here we explored whether and how anterior cingulate cortex (ACC) glutamate relates to striatal BOLD-responses during cognitive control. We used proton magnetic resonance spectroscopy to evaluate glutamate-to-creatine ratios in 62 participants (probands with ADHD n=19, unaffected siblings n=24 and typical controls n=19, mean age=20.4). Spectra were collected from the ACC and the dorsal striatum and glutamate-to-creatine ratios were extracted. Thirty-two participants additionally took part in a functional magnetic resonance imaging (fMRI) Stroop task to investigate neural responses during cognitive control. Given small sample sizes we report all effects with p<0.10 along with effect sizes. ADHD subjects showed decreased glutamate-to-creatine ratios in the ACC (F=3.81, p=0.059, ηp2=0.104; medium to large effect-size) compared with controls. Importantly, decreased ACC glutamate-to-creatine ratios were associated with increased striatal BOLD-responses during cognitive control (rho=-0.41, p=0.019; medium effect-size), independent of diagnosis. Increased striatal responses tended to be associated with more errors during the task and more hyperactivity/impulsivity symptoms (rho=0.34, p=0.058 and rho=0.33, p=0.068, respectively); the latter two being correlated too (rho=0.37, p=0.037), all with medium effect sizes. Our results suggest that ACC glutamate in ADHD might be associated with striatal (dys)functioning during the Stroop task, supporting the role of fronto-striatal glutamate in cognitive control.
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Affiliation(s)
- Jilly Naaijen
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - David J Lythgoe
- King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Neuroimaging, London, United Kingdom
| | - Marcel P Zwiers
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Catharina A Hartman
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - Pieter J Hoekstra
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - Jan K Buitelaar
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands; Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands
| | - Esther Aarts
- Donders Institute for Brain, Cognition and Behavior, Centre for Cognitive Neuroimaging, Radboud University, Nijmegen, The Netherlands
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18
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Faraone SV. The pharmacology of amphetamine and methylphenidate: Relevance to the neurobiology of attention-deficit/hyperactivity disorder and other psychiatric comorbidities. Neurosci Biobehav Rev 2018; 87:255-270. [PMID: 29428394 DOI: 10.1016/j.neubiorev.2018.02.001] [Citation(s) in RCA: 297] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/25/2018] [Accepted: 02/05/2018] [Indexed: 12/20/2022]
Abstract
Psychostimulants, including amphetamines and methylphenidate, are first-line pharmacotherapies for individuals with attention-deficit/hyperactivity disorder (ADHD). This review aims to educate physicians regarding differences in pharmacology and mechanisms of action between amphetamine and methylphenidate, thus enhancing physician understanding of psychostimulants and their use in managing individuals with ADHD who may have comorbid psychiatric conditions. A systematic literature review of PubMed was conducted in April 2017, focusing on cellular- and brain system-level effects of amphetamine and methylphenidate. The primary pharmacologic effect of both amphetamine and methylphenidate is to increase central dopamine and norepinephrine activity, which impacts executive and attentional function. Amphetamine actions include dopamine and norepinephrine transporter inhibition, vesicular monoamine transporter 2 (VMAT-2) inhibition, and monoamine oxidase activity inhibition. Methylphenidate actions include dopamine and norepinephrine transporter inhibition, agonist activity at the serotonin type 1A receptor, and redistribution of the VMAT-2. There is also evidence for interactions with glutamate and opioid systems. Clinical implications of these actions in individuals with ADHD with comorbid depression, anxiety, substance use disorder, and sleep disturbances are discussed.
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Affiliation(s)
- Stephen V Faraone
- Departments of Psychiatry and of Neuroscience and Physiology, State University of New York (SUNY) Upstate Medical University, Syracuse, NY, United States; K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, University of Bergen, Bergen, Norway.
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19
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Changes in serum levels of kynurenine metabolites in paediatric patients affected by ADHD. Eur Child Adolesc Psychiatry 2017; 26:1433-1441. [PMID: 28527020 DOI: 10.1007/s00787-017-1002-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 05/12/2017] [Indexed: 12/14/2022]
Abstract
This study aims at determining serum levels of tryptophan and other metabolites of the kynurenine pathway in children with attention deficit hyperactivity disorder (ADHD) compared to healthy controls. Such metabolites interact with glutamate receptors in the central nervous system, potentially modulating mechanisms that are pivotal in ADHD and thus potentially representing peripheral biomarkers of the disorder. We measured serum levels of tryptophan and some metabolites of the kynurenine pathway in 102 children with ADHD and 62 healthy controls by liquid chromatography-tandem mass spectrometry (LC-MS/MS). As compared to healthy controls, children with ADHD showed a reduction in serum levels of anthranilic acid (-60%), kynurenic acid (-11.2%), and xanthurenic acid (-12.5%). In contrast, serum levels of tryptophan (+11.0%) and kynurenine (+48.6%) were significantly enhanced, and levels of quinolinic acid were unchanged in children with ADHD. In a logistic regression model, the presence of ADHD was predicted by low anthranilic acid and high tryptophan levels. These findings support the involvement of the kynurenine pathway in the pathophysiology of ADHD and suggest that anthranilic acid and tryptophan levels should be investigated as potential peripheral biomarker for ADHD.
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20
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Naaijen J, Forde NJ, Lythgoe DJ, Akkermans SEA, Openneer TJC, Dietrich A, Zwiers MP, Hoekstra PJ, Buitelaar JK. Fronto-striatal glutamate in children with Tourette's disorder and attention-deficit/hyperactivity disorder. NEUROIMAGE-CLINICAL 2016; 13:16-23. [PMID: 27909683 PMCID: PMC5124361 DOI: 10.1016/j.nicl.2016.11.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 10/26/2016] [Accepted: 11/14/2016] [Indexed: 01/31/2023]
Abstract
Objective Both Tourette's disorder (TD) and attention-deficit/hyperactivity disorder (ADHD) have been related to abnormalities in glutamatergic neurochemistry in the fronto-striatal circuitry. TD and ADHD often co-occur and the neural underpinnings of this co-occurrence have been insufficiently investigated in prior studies. Method We used proton magnetic resonance spectroscopy (1H-MRS) in children between 8 and 12 years of age (TD n = 15, ADHD n = 39, TD + ADHD n = 29, and healthy controls n = 53) as an in vivo method of evaluating glutamate concentrations in the fronto-striatal circuit. Spectra were collected on a 3 Tesla Siemens scanner from two voxels in each participant: the anterior cingulate cortex (ACC) and the left dorsal striatum. LC-model was used to process spectra and generate glutamate concentrations in institutional units. A one-way analysis of variance was performed to determine significant effects of diagnostic group on glutamate concentrations. Results We did not find any group differences in glutamate concentrations in either the ACC (F(3132) = 0.97, p = 0.41) or striatum (F(3121) = 0.59, p = 0.62). Furthermore, variation in glutamate concentration in these regions was unrelated to age, sex, medication use, IQ, tic, or ADHD severity. Obsessive–compulsive (OC) symptoms were positively correlated with ACC glutamate concentration within the participants with TD (rho = 0.35, puncorrected = 0.02). Conclusion We found no evidence for glutamatergic neuropathology in TD or ADHD within the fronto-striatal circuits. However, the correlation of OC-symptoms with ACC glutamate concentrations suggests that altered glutamatergic transmission is involved in OC-symptoms within TD, but this needs further investigation. Large pediatric sample of ADHD and TD participants 3 Tesla proton MRS utilized to investigate fronto-striatal glutamate concentrations No differences in glutamate concentrations in the disorder groups compared with controls ACC glutamate concentrations associated with obsessive–compulsive symptoms in TD
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Affiliation(s)
- Jilly Naaijen
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Natalie J Forde
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - David J Lythgoe
- King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Neuroimaging, London, United Kingdom
| | - Sophie E A Akkermans
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Thaira J C Openneer
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - Andrea Dietrich
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - Marcel P Zwiers
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Pieter J Hoekstra
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - Jan K Buitelaar
- Department of Cognitive Neuroscience, Donders Institute of Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands; Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands
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21
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Wyrwich KW, Shaffer S, Gries K, Auguste P, Mooney KH, Prasad S, Bilder DA. Content Validity of the ADHD Rating Scale (ADHD RS-IV) and Adult ADHD Self-Report Scale (ASRS) in Phenylketonuria. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2016. [DOI: 10.1177/2326409816639316] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
| | | | | | | | | | | | - Deborah A. Bilder
- Department of Psychiatry, University of Utah, Salt Lake City, UT, USA
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22
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Ende G, Cackowski S, Van Eijk J, Sack M, Demirakca T, Kleindienst N, Bohus M, Sobanski E, Krause-Utz A, Schmahl C. Impulsivity and Aggression in Female BPD and ADHD Patients: Association with ACC Glutamate and GABA Concentrations. Neuropsychopharmacology 2016; 41:410-8. [PMID: 26040503 PMCID: PMC5130117 DOI: 10.1038/npp.2015.153] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 04/29/2015] [Accepted: 05/15/2015] [Indexed: 11/09/2022]
Abstract
Borderline personality disorder (BPD) and attention-deficit-hyperactivity disorder (ADHD) are both characterized by high impulsivity and difficulties in controlling anger and aggression. In BPD, comorbid ADHD may further increase impulsivity. For both disorders, altered MR spectroscopy levels of the neurotransmitters glutamate and GABA as well as some correlations with impulsivity were previously reported. The objective of this study was to investigate the neurotransmitters glutamate and GABA in relation to impulsivity and aggression as expressed in the anterior cingulate cortex (ACC) in groups of female patients with BPD and ADHD, respectively. Associations of glutamate and GABA levels with further BPD (symptom severity) and ADHD aspects (hyperactivity and inattention) were exploratively evaluated. 1H MR spectra were acquired at 3T to determine glutamate to total creatine ratios (Glu/tCr) and GABA levels from the ACC in a BPD group (n=26), an ADHD group (n=22), and a healthy control (HC) group (n=30); all participants were females. Both patient groups showed higher scores on self-reported impulsivity, anger, and aggression compared with HCs. ACC GABA levels were significantly lower in ADHD than HC. Although measures of impulsivity were positively related to glutamate and negatively to GABA, for aggression only a negative correlation with GABA could be demonstrated. These data provide human in vivo evidence for the role of ACC Glu/tCr and GABA in impulsivity and aggression. If distinct associations of Glu/tCr and GABA for BPD and ADHD can be confirmed in future studies, this might yield implications for more specific pharmacological treatments.
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Affiliation(s)
- Gabriele Ende
- Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany,Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, J5, Mannheim D-68159, Germany. Tel: +49 621 1703 2971; Fax: +49 621 1703 702971; E-mail:
| | - Sylvia Cackowski
- Department of Psychosomatic Medicine and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Julia Van Eijk
- Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Markus Sack
- Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Traute Demirakca
- Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Nikolaus Kleindienst
- Department of Psychosomatic Medicine and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Martin Bohus
- Department of Psychosomatic Medicine and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Esther Sobanski
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Annegret Krause-Utz
- Department of Psychosomatic Medicine and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Christian Schmahl
- Department of Psychosomatic Medicine and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
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23
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Endres D, Perlov E, Maier S, Feige B, Nickel K, Goll P, Bubl E, Lange T, Glauche V, Graf E, Ebert D, Sobanski E, Philipsen A, Tebartz van Elst L. Normal Neurochemistry in the Prefrontal and Cerebellar Brain of Adults with Attention-Deficit Hyperactivity Disorder. Front Behav Neurosci 2015; 9:242. [PMID: 26441572 PMCID: PMC4585345 DOI: 10.3389/fnbeh.2015.00242] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 08/24/2015] [Indexed: 01/07/2023] Open
Abstract
Attention-deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder. In an attempt to extend earlier neurochemical findings, we organized a magnetic resonance spectroscopy (MRS) study as part of a large, government-funded, prospective, randomized, multicenter clinical trial comparing the effectiveness of specific psychotherapy with counseling and stimulant treatment with placebo treatment (Comparison of Methylphenidate and Psychotherapy Study). We report the baseline neurochemical data for the anterior cingulate cortex (ACC) and the cerebellum in a case–control setting. For the trial, 1,480 adult patients were contacted for participation, 518 were assessed for eligibility, 433 were randomized, and 187 were potentially eligible for neuroimaging. The control group included 119 healthy volunteers. Single-voxel proton MRS was performed. In the patient group, 113 ACC and 104 cerebellar spectra fulfilled all quality criteria for inclusion in statistical calculations, as did 82 ACC and 78 cerebellar spectra in the control group. We did not find any significant neurometabolic differences between the ADHD and control group in the ACC (Wilks’ lambda test: p = 0.97) or in the cerebellum (p = 0.62). Thus, we were unable to replicate earlier findings in this methodologically sophisticated study. We discuss our findings in the context of a comprehensive review of other MRS studies on ADHD and a somewhat skeptical neuropsychiatric research perspective. As in other neuropsychiatric disorders, the unclear nosological status of ADHD might be an explanation for false-negative findings.
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Affiliation(s)
- Dominique Endres
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Evgeniy Perlov
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Simon Maier
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Bernd Feige
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Kathrin Nickel
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Peter Goll
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Emanuel Bubl
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Thomas Lange
- Department of Radiology, Medical Physics, University Medical Center Freiburg , Freiburg , Germany ; Freiburg Institute for Advanced Studies, Albert-Ludwigs-University , Freiburg , Germany
| | - Volkmar Glauche
- Department of Neurology, University Medical Center Freiburg , Freiburg , Germany
| | - Erika Graf
- Clinical Trials Unit, University Medical Center Freiburg , Freiburg , Germany
| | - Dieter Ebert
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Esther Sobanski
- Clinic for Psychiatry and Psychotherapy, Central Institute for Mental Health Mannheim , Mannheim , Germany
| | - Alexandra Philipsen
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
| | - Ludger Tebartz van Elst
- Section for Experimental Neuropsychiatry, Department for Psychiatry and Psychotherapy, University Medical Center Freiburg , Freiburg , Germany
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Bollmann S, Ghisleni C, Poil SS, Martin E, Ball J, Eich-Höchli D, Edden RAE, Klaver P, Michels L, Brandeis D, O'Gorman RL. Developmental changes in gamma-aminobutyric acid levels in attention-deficit/hyperactivity disorder. Transl Psychiatry 2015; 5:e589. [PMID: 26101852 PMCID: PMC4490289 DOI: 10.1038/tp.2015.79] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 04/27/2015] [Accepted: 05/04/2015] [Indexed: 12/20/2022] Open
Abstract
While the neurobiological basis and developmental course of attention-deficit/hyperactivity disorder (ADHD) have not yet been fully established, an imbalance between inhibitory/excitatory neurotransmitters is thought to have an important role in the pathophysiology of ADHD. This study examined the changes in cerebral levels of GABA+, glutamate and glutamine in children and adults with ADHD using edited magnetic resonance spectroscopy. We studied 89 participants (16 children with ADHD, 19 control children, 16 adults with ADHD and 38 control adults) in a subcortical voxel (children and adults) and a frontal voxel (adults only). ADHD adults showed increased GABA+ levels relative to controls (P = 0.048), while ADHD children showed no difference in GABA+ in the subcortical voxel (P > 0.1), resulting in a significant age by disorder interaction (P = 0.026). Co-varying for age in an analysis of covariance model resulted in a nonsignificant age by disorder interaction (P = 0.06). Glutamine levels were increased in children with ADHD (P = 0.041), but there was no significant difference in adults (P > 0.1). Glutamate showed no difference between controls and ADHD patients but demonstrated a strong effect of age across both groups (P < 0.001). In conclusion, patients with ADHD show altered levels of GABA+ in a subcortical voxel which change with development. Further, we found increased glutamine levels in children with ADHD, but this difference normalized in adults. These observed imbalances in neurotransmitter levels are associated with ADHD symptomatology and lend new insight in the developmental trajectory and pathophysiology of ADHD.
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Affiliation(s)
- S Bollmann
- Center for MR-Research, University Children's Hospital Zurich, Zürich, Switzerland,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland,Zurich Center for Integrative Human Physiology, University of Zurich, Zürich, Switzerland,Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zürich, Switzerland,Centre for Advanced Imaging, University of Queensland, Brisbane, QLD, Australia
| | - C Ghisleni
- Center for MR-Research, University Children's Hospital Zurich, Zürich, Switzerland,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland,Zurich Center for Integrative Human Physiology, University of Zurich, Zürich, Switzerland
| | - S-S Poil
- Center for MR-Research, University Children's Hospital Zurich, Zürich, Switzerland,Zurich Center for Integrative Human Physiology, University of Zurich, Zürich, Switzerland
| | - E Martin
- Center for MR-Research, University Children's Hospital Zurich, Zürich, Switzerland,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland
| | - J Ball
- Department of Child and Adolescent Psychiatry, University of Zurich, Zürich, Switzerland
| | - D Eich-Höchli
- Psychiatric University Hospital, Zürich, Switzerland
| | - R A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA,F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - P Klaver
- Center for MR-Research, University Children's Hospital Zurich, Zürich, Switzerland,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland,Zurich Center for Integrative Human Physiology, University of Zurich, Zürich, Switzerland,Department of Psychology, University of Zurich, Zürich, Switzerland
| | - L Michels
- Institute of Neuroradiology, University Hospital of Zurich, Zürich, Switzerland
| | - D Brandeis
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland,Zurich Center for Integrative Human Physiology, University of Zurich, Zürich, Switzerland,Department of Child and Adolescent Psychiatry, University of Zurich, Zürich, Switzerland,Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health Mannheim, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - R L O'Gorman
- Center for MR-Research, University Children's Hospital Zurich, Zürich, Switzerland,Zurich Center for Integrative Human Physiology, University of Zurich, Zürich, Switzerland,Pediatric Research Center, University Children's Hospital Zurich, Zürich, Switzerland,Center for MR-Research, University Children's Hospital Zurich, Steinwiesstrasse 75, Zürich CH 8032, Switzerland. E-mail:
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25
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Naaijen J, Lythgoe DJ, Amiri H, Buitelaar JK, Glennon JC. Fronto-striatal glutamatergic compounds in compulsive and impulsive syndromes: A review of magnetic resonance spectroscopy studies. Neurosci Biobehav Rev 2015; 52:74-88. [DOI: 10.1016/j.neubiorev.2015.02.009] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 12/20/2014] [Accepted: 02/13/2015] [Indexed: 11/29/2022]
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26
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Miller EM, Pomerleau F, Huettl P, Gerhardt GA, Glaser PEA. Aberrant glutamate signaling in the prefrontal cortex and striatum of the spontaneously hypertensive rat model of attention-deficit/hyperactivity disorder. Psychopharmacology (Berl) 2014; 231:3019-29. [PMID: 24682500 DOI: 10.1007/s00213-014-3479-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 01/28/2014] [Indexed: 01/09/2023]
Abstract
RATIONALE Attention-deficit/hyperactivity disorder (ADHD) is thought to involve hypofunctional catecholamine systems in the striatum, nucleus accumbens, and prefrontal cortex (PFC); however, recent clinical evidence has implicated glutamate dysfunction in the pathophysiology of ADHD. Recent studies show that increased stimulation of dopamine D2 and D4 receptors causes inhibition of N-methyl-D-aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, respectively. The spontaneously hypertensive rat (SHR) model of ADHD combined type (C) has been found to have a hypofunctional dopamine system in the ventral striatum, nucleus accumbens, and PFC compared to the control Wistar Kyoto (WKY) strain. OBJECTIVES Based on the current understanding of typical dopamine-glutamate interactions, we hypothesized that the SHR model of ADHD would have a hyperfunctional glutamate system terminating in the striatum, nucleus accumbens, and PFC. RESULTS High-speed amperometric recordings combined with four-channel microelectrode arrays to directly measure glutamate dynamics showed increased evoked glutamate release in the PFC (cingulate and infralimbic cortices, p < 0.05) and also in the striatum (p < 0.05) of the SHR (ADHD-C) as compared to the WKY. Finally, glutamate uptake was discovered to be aberrant in the PFC, but not the striatum, of the SHR when compared to the control WKY strain. CONCLUSIONS These results suggest that the glutamatergic system in the PFC of the SHR model of ADHD is hyperfunctional and that targeting glutamate in the PFC could lead to the development of novel therapeutics for the treatment of ADHD.
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Affiliation(s)
- Erin M Miller
- Department of Anatomy and Neurobiology, University of Kentucky Chandler Medical Center, Lexington, KY, 40536, USA
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27
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Altabella L, Zoratto F, Adriani W, Canese R. MR imaging-detectable metabolic alterations in attention deficit/hyperactivity disorder: from preclinical to clinical studies. AJNR Am J Neuroradiol 2014; 35:S55-63. [PMID: 24481327 DOI: 10.3174/ajnr.a3843] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
MR spectroscopy represents one of the most suitable in vivo tool to assess neurochemical dysfunction in several brain disorders, including attention deficit/hyperactivity disorder. This is the most common neuropsychiatric disorder in childhood and adolescence, which persists into adulthood (in approximately 30%-50% of cases). In past years, many studies have applied different MR spectroscopy techniques to investigate the pathogenesis and effect of conventional treatments. In this article, we review the most recent clinical and preclinical MR spectroscopy results on subjects with attention deficit/hyperactivity disorder and animal models, from childhood to adulthood. We found that the most investigated brain regions were the (pre)frontal lobes and striatum, both involved in the frontostriatal circuits and networks that are known to be impaired in this pathology. Neurometabolite alterations were detected in several regions: the NAA, choline, and glutamatergic compounds. The creatine pool was also altered when an absolute quantitative protocol was adopted. In particular, glutamate was increased in children with attention deficit/hyperactivity disorder, and this can apparently be reversed by methylphenidate treatment. The main difficulties in reviewing MR spectroscopy studies were in the nonhomogeneity of the analyzed subjects, the variety of the investigated brain regions, and also the use of different MR spectroscopy techniques. As for possible improvements in future studies, we recommend the use of standardized protocols and the analysis of other brain regions of particular interest for attention deficit hyperactivity disorder, like the hippocampus, limbic structures, thalamus, and cerebellum.
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Affiliation(s)
- L Altabella
- From the Department of Cell Biology and Neurosciences (L.A., F.Z., W.A., R.C.), Istituto Superiore di Sanità, Rome, Italy
| | - F Zoratto
- From the Department of Cell Biology and Neurosciences (L.A., F.Z., W.A., R.C.), Istituto Superiore di Sanità, Rome, ItalyBambino Gesù Children's Hospital IRCCS (F.Z.), Rome, Italy
| | - W Adriani
- From the Department of Cell Biology and Neurosciences (L.A., F.Z., W.A., R.C.), Istituto Superiore di Sanità, Rome, Italy
| | - R Canese
- From the Department of Cell Biology and Neurosciences (L.A., F.Z., W.A., R.C.), Istituto Superiore di Sanità, Rome, Italy
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28
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Maltezos S, Horder J, Coghlan S, Skirrow C, O'Gorman R, Lavender TJ, Mendez MA, Mehta M, Daly E, Xenitidis K, Paliokosta E, Spain D, Pitts M, Asherson P, Lythgoe DJ, Barker GJ, Murphy DG. Glutamate/glutamine and neuronal integrity in adults with ADHD: a proton MRS study. Transl Psychiatry 2014; 4:e373. [PMID: 24643164 PMCID: PMC3966039 DOI: 10.1038/tp.2014.11] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 01/06/2014] [Accepted: 01/09/2014] [Indexed: 01/19/2023] Open
Abstract
There is increasing evidence that abnormalities in glutamate signalling may contribute to the pathophysiology of attention-deficit hyperactivity disorder (ADHD). Proton magnetic resonance spectroscopy ([1H]MRS) can be used to measure glutamate, and also its metabolite glutamine, in vivo. However, few studies have investigated glutamate in the brain of adults with ADHD naive to stimulant medication. Therefore, we used [1H]MRS to measure the combined signal of glutamate and glutamine (Glu+Gln; abbreviated as Glx) along with other neurometabolites such as creatine (Cr), N-acetylaspartate (NAA) and choline. Data were acquired from three brain regions, including two implicated in ADHD-the basal ganglia (caudate/striatum) and the dorsolateral prefrontal cortex (DLPFC)-and one 'control' region-the medial parietal cortex. We compared 40 adults with ADHD, of whom 24 were naive for ADHD medication, whereas 16 were currently on stimulants, against 20 age, sex and IQ-matched healthy controls. We found that compared with controls, adult ADHD participants had a significantly lower concentration of Glx, Cr and NAA in the basal ganglia and Cr in the DLPFC, after correction for multiple comparisons. There were no differences between stimulant-treated and treatment-naive ADHD participants. In people with untreated ADHD, lower basal ganglia Glx was significantly associated with more severe symptoms of inattention. There were no significant differences in the parietal 'control' region. We suggest that subcortical glutamate and glutamine have a modulatory role in ADHD adults; and that differences in glutamate-glutamine levels are not explained by use of stimulant medication.
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Affiliation(s)
- S Maltezos
- Adult ADHD Service, The Maudsley Hospital, London, UK,King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK
| | - J Horder
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK,King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, PO Box 50, London SE5 8AF, UK. E-mail:
| | - S Coghlan
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK
| | - C Skirrow
- King's College London, MRC Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK
| | - R O'Gorman
- King's College London, Department of Neuroimaging, Institute of Psychiatry, London, UK
| | - T J Lavender
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK
| | - M A Mendez
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK,Autism Assessment and Behavioural Genetics Clinic, South London and Maudsley NHS Foundation Trust, Bethlem Royal Hospital, Beckenham, UK
| | - M Mehta
- King's College London, Department of Neuroimaging, Institute of Psychiatry, London, UK
| | - E Daly
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK
| | - K Xenitidis
- Adult ADHD Service, The Maudsley Hospital, London, UK,King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK
| | - E Paliokosta
- Adult ADHD Service, The Maudsley Hospital, London, UK
| | - D Spain
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK,Autism Assessment and Behavioural Genetics Clinic, South London and Maudsley NHS Foundation Trust, Bethlem Royal Hospital, Beckenham, UK
| | - M Pitts
- Adult ADHD Service, The Maudsley Hospital, London, UK
| | - P Asherson
- Adult ADHD Service, The Maudsley Hospital, London, UK,King's College London, MRC Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK
| | - D J Lythgoe
- King's College London, Department of Neuroimaging, Institute of Psychiatry, London, UK
| | - G J Barker
- King's College London, Department of Neuroimaging, Institute of Psychiatry, London, UK
| | - D G Murphy
- King's College London, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, London, UK,Autism Assessment and Behavioural Genetics Clinic, South London and Maudsley NHS Foundation Trust, Bethlem Royal Hospital, Beckenham, UK,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, King's College London, London, UK
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29
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Age-related change of neurochemical abnormality in attention-deficit hyperactivity disorder: a meta-analysis. Neurosci Biobehav Rev 2013; 37:1692-701. [PMID: 23735885 DOI: 10.1016/j.neubiorev.2013.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 04/19/2013] [Accepted: 04/30/2013] [Indexed: 12/18/2022]
Abstract
Prevalence and symptoms of attention-deficit hyperactivity disorder (ADHD) change with advancing age. However, neurochemical background of such age-related change is yet to be elucidated. We therefore conducted a meta-analysis of 16 proton magnetic resonance spectroscopy studies comprising 270 individuals with ADHD and 235 controls. Standardized mean differences were calculated and used as an effect size. Sensitivity analyses and meta-regression to explore the effect of age on neurochemical abnormality were performed. A random effects model identified a significantly higher-than-normal N-acetylaspartate (NAA) in the medial prefrontal cortex (mPFC), but no significant differences of other metabolites in that area. No significant difference in metabolite levels was demonstrated in any other region. Sensitivity analysis of children with ADHD revealed significantly higher-than-normal NAA, whereas no significant difference was found in adults with ADHD. Meta-regression revealed significant correlation between advanced age and normal levels of NAA in the mPFC, suggesting that age-dependent abnormality of NAA level in the mPFC is a potential neural basis of age-related change of symptoms of ADHD.
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