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Parlatini V, Bellato A, Murphy D, Cortese S. From neurons to brain networks, pharmacodynamics of stimulant medication for ADHD. Neurosci Biobehav Rev 2024; 164:105841. [PMID: 39098738 DOI: 10.1016/j.neubiorev.2024.105841] [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: 04/17/2024] [Revised: 07/25/2024] [Accepted: 08/01/2024] [Indexed: 08/06/2024]
Abstract
Stimulants represent the first line pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD) and are among the most prescribed psychopharmacological treatments. Their mechanism of action at synaptic level has been extensively studied. However, it is less clear how their mechanism of action determines clinically observed benefits. To help bridge this gap, we provide a comprehensive review of stimulant effects, with an emphasis on nuclear medicine and magnetic resonance imaging (MRI) findings. There is evidence that stimulant-induced modulation of dopamine and norepinephrine neurotransmission optimizes engagement of task-related brain networks, increases perceived saliency, and reduces interference from the default mode network. An acute administration of stimulants may reduce brain alterations observed in untreated individuals in fronto-striato-parieto-cerebellar networks during tasks or at rest. Potential effects of prolonged treatment remain controversial. Overall, neuroimaging has fostered understanding on stimulant mechanism of action. However, studies are often limited by small samples, short or no follow-up, and methodological heterogeneity. Future studies should address age-related and longer-term effects, potential differences among stimulants, and predictors of treatment response.
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Affiliation(s)
- Valeria Parlatini
- School of Psychology, University of Southampton, Southampton, United Kingdom; Centre for Innovation in Mental Health, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Institute of Translational Neurodevelopment, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, United Kingdom; Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, United Kingdom; Solent NHS Trust, Southampton, United Kingdom.
| | - Alessio Bellato
- School of Psychology, University of Southampton, Southampton, United Kingdom; Centre for Innovation in Mental Health, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Solent NHS Trust, Southampton, United Kingdom; School of Psychology, University of Nottingham, Semenyih, Malaysia
| | - Declan Murphy
- Institute of Translational Neurodevelopment, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, United Kingdom; Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, United Kingdom
| | - Samuele Cortese
- School of Psychology, University of Southampton, Southampton, United Kingdom; Centre for Innovation in Mental Health, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Solent NHS Trust, Southampton, United Kingdom; Mind and Neurodevelopment (MiND) Research Group, University of Nottingham, Semenyih, Malaysia; Clinical and Experimental Sciences (CNS and Psychiatry), Faculty of Medicine, University of Southampton, Southampton, United Kingdom; Hassenfeld Children's Hospital at NYU Langone, New York University Child Study Center, New York, NY, USA
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Mizuno Y, Cai W, Supekar K, Makita K, Takiguchi S, Silk TJ, Tomoda A, Menon V. Methylphenidate Enhances Spontaneous Fluctuations in Reward and Cognitive Control Networks in Children With Attention-Deficit/Hyperactivity Disorder. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2023; 8:271-280. [PMID: 36717325 DOI: 10.1016/j.bpsc.2022.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 09/06/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022]
Abstract
BACKGROUND Methylphenidate, a first-line treatment for attention-deficit/hyperactivity disorder (ADHD), is thought to influence dopaminergic neurotransmission in the nucleus accumbens (NAc) and its associated brain circuitry, but this hypothesis has yet to be systematically tested. METHODS We conducted a randomized, placebo-controlled, double-blind crossover trial including 27 children with ADHD. Children with ADHD were scanned twice with resting-state functional magnetic resonance imaging under methylphenidate and placebo conditions, along with assessment of sustained attention. We examined spontaneous neural activity in the NAc and the salience, frontoparietal, and default mode networks and their links to behavioral changes. Replicability of methylphenidate effects on spontaneous neural activity was examined in a second independent cohort. RESULTS Methylphenidate increased spontaneous neural activity in the NAc and the salience and default mode networks. Methylphenidate-induced changes in spontaneous activity patterns in the default mode network were associated with improvements in intraindividual response variability during a sustained attention task. Critically, despite differences in clinical trial protocols and data acquisition parameters, the NAc and the salience and default mode networks showed replicable patterns of methylphenidate-induced changes in spontaneous activity across two independent cohorts. CONCLUSIONS We provide reproducible evidence demonstrating that methylphenidate enhances spontaneous neural activity in NAc and cognitive control networks in children with ADHD, resulting in more stable sustained attention. Our findings identified a novel neural mechanism underlying methylphenidate treatment in ADHD to inform the development of clinically useful biomarkers for evaluating treatment outcomes.
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Affiliation(s)
- Yoshifumi Mizuno
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Research Center for Child Mental Development, University of Fukui, Fukui, Japan; Division of Developmental Higher Brain Functions, United Graduate School of Child Development, University of Fukui, Fukui, Japan; Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan.
| | - Weidong Cai
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Wu Tsai Neurosciences Institute, Stanford University, Stanford, California; Maternal & Child Health Research Institute, Stanford University, Stanford, California
| | - Kaustubh Supekar
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Wu Tsai Neurosciences Institute, Stanford University, Stanford, California; Maternal & Child Health Research Institute, Stanford University, Stanford, California
| | - Kai Makita
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan; Division of Developmental Higher Brain Functions, United Graduate School of Child Development, University of Fukui, Fukui, Japan
| | - Shinichiro Takiguchi
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, University of Fukui, Fukui, Japan; Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan
| | - Timothy J Silk
- Centre for Social and Early Emotional Development and School of Psychology, Deakin University, Geelong, Victoria, Australia; Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Akemi Tomoda
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan; Division of Developmental Higher Brain Functions, United Graduate School of Child Development, University of Fukui, Fukui, Japan; Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan
| | - Vinod Menon
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Department of Neurology and Neurological Sciences, Stanford University, Stanford, California; Wu Tsai Neurosciences Institute, Stanford University, Stanford, California; Maternal & Child Health Research Institute, Stanford University, Stanford, California.
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da Silva BS, Grevet EH, Silva LCF, Ramos JKN, Rovaris DL, Bau CHD. An overview on neurobiology and therapeutics of attention-deficit/hyperactivity disorder. DISCOVER MENTAL HEALTH 2023; 3:2. [PMID: 37861876 PMCID: PMC10501041 DOI: 10.1007/s44192-022-00030-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/29/2022] [Indexed: 10/21/2023]
Abstract
Attention-Deficit/Hyperactivity Disorder (ADHD) is a prevalent psychiatric condition characterized by developmentally inappropriate symptoms of inattention and/or hyperactivity/impulsivity, which leads to impairments in the social, academic, and professional contexts. ADHD diagnosis relies solely on clinical assessment based on symptom evaluation and is sometimes challenging due to the substantial heterogeneity of the disorder in terms of clinical and pathophysiological aspects. Despite the difficulties imposed by the high complexity of ADHD etiology, the growing body of research and technological advances provide good perspectives for understanding the neurobiology of the disorder. Such knowledge is essential to refining diagnosis and identifying new therapeutic options to optimize treatment outcomes and associated impairments, leading to improvements in all domains of patient care. This review is intended to be an updated outline that addresses the etiological and neurobiological aspects of ADHD and its treatment, considering the impact of the "omics" era on disentangling the multifactorial architecture of ADHD.
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Affiliation(s)
- Bruna Santos da Silva
- ADHD and Developmental Psychiatry Programs, Hospital de Clínicas de Porto Alegre, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
- Department of Genetics and Graduate Program in Genetics and Molecular Biology, Instituto de Biociências, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas Universidade de Sao Paulo, São Paulo, Brazil
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Eugenio Horacio Grevet
- ADHD and Developmental Psychiatry Programs, Hospital de Clínicas de Porto Alegre, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
- Department of Psychiatry and Graduate Program in Psychiatry and Behavioral Sciences, Faculdade de Medicina, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
| | - Luiza Carolina Fagundes Silva
- ADHD and Developmental Psychiatry Programs, Hospital de Clínicas de Porto Alegre, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
- Department of Psychiatry and Graduate Program in Psychiatry and Behavioral Sciences, Faculdade de Medicina, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
| | - João Kleber Neves Ramos
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas Universidade de Sao Paulo, São Paulo, Brazil
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Diego Luiz Rovaris
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas Universidade de Sao Paulo, São Paulo, Brazil
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Claiton Henrique Dotto Bau
- ADHD and Developmental Psychiatry Programs, Hospital de Clínicas de Porto Alegre, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil.
- Department of Genetics and Graduate Program in Genetics and Molecular Biology, Instituto de Biociências, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil.
- Department of Psychiatry and Graduate Program in Psychiatry and Behavioral Sciences, Faculdade de Medicina, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil.
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Shang CY, Chou TL, Hsieh CY, Gau SSF. A Counting Stroop Functional Magnetic Resonance Imaging Study on the Effects of ORADUR-Methylphenidate in Drug-Naive Children with Attention-Deficit/Hyperactivity Disorder. J Child Adolesc Psychopharmacol 2022; 32:467-475. [PMID: 36251766 PMCID: PMC9700368 DOI: 10.1089/cap.2022.0024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective: Methylphenidate is effective in reducing the clinical symptoms of patients with attention-deficit/hyperactivity disorder (ADHD). ORADUR®-methylphenidate is a new extended-release preparation of methylphenidate. This study aimed at identifying brain regions with activation changes and their correlations with neuropsychological functions after treatment with ORADUR-methylphenidate in children with ADHD. Methods: We recruited drug-naive children with ADHD and age- and sex-matched typically developing (TD) children. They were all scanned with the functional magnetic resonance imaging (fMRI) during the counting Stroop task at baseline, and those with ADHD had the second fMRI assessment after 8-week treatment with ORADUR-methylphenidate. The Rapid Visual Information Processing (RVP) and Conners' Continuous Performance Test (CCPT) were used to assess the attention performance of the ADHD (before and after treatment) and TD groups. Results: ORADUR-methylphenidate significantly decreased inattention (Cohen d = 2.17) and hyperactivity-impulsivity (Cohen d = 0.98) symptoms. We found less activation in the right inferior frontal gyrus (rIFG) in the pre-treatment ADHD children than TD children and greater treatment-induced activation in the dorsal anterior cingulate cortex (dACC) and the right dorsolateral prefrontal cortex (rDLPFC). There was no significant difference between the post-treatment ADHD and TD groups. However, the treatment-related activations in the dACC, rDLPFC, and rIFG were significantly correlated with CCPT and RVP measures. Conclusions: Our findings indicated that ORADUR-methylphenidate increased brain activations in the dACC, rDLPFC, and rIFG in children with ADHD, associated with improved focused attention, reduced impulsivity, and enhanced inhibition control. Activities of these brain regions might be biomarkers for the treatment effectiveness of methylphenidate for ADHD. Clinical Trials Registration: ClinicalTrials.gov number, NCT02450890.
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Affiliation(s)
- Chi-Yung Shang
- Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Tai-Li Chou
- Department of Psychology, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan
| | - Cheng-Yu Hsieh
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Susan Shur-Fen Gau
- Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan.,Department of Psychology, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan.,Address correspondence to: Susan Shur-Fen Gau, MD, PhD, Department of Psychiatry, National Taiwan University Hospital and College of Medicine, No. 7, Chung-Shan South Road, Taipei 10002, Taiwan
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Çetin FH, Barış Usta M, Aydın S, Güven AS. A Case Study on EEG Analysis: Embedding Entropy Estimations Indicate the Decreased Neuro-Cortical Complexity Levels Mediated by Methylphenidate Treatment in Children with ADHD. Clin EEG Neurosci 2022; 53:406-417. [PMID: 34923863 DOI: 10.1177/15500594211064008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective: Complexity analysis is a method employed to understand the activity of the brain. The effect of methylphenidate (MPH) treatment on neuro-cortical complexity changes is still unknown. This study aimed to reveal how MPH treatment affects the brain complexity of children with attention deficit hyperactivity disorder (ADHD) using entropy-based quantitative EEG analysis. Three embedding entropy approaches were applied to short segments of both pre- and post- medication EEG series. EEG signals were recorded for 25 boys with combined type ADHD prior to the administration of MPH and at the end of the first month of the treatment. Results: In comparison to Approximate Entropy (ApEn) and Sample Entropy (SampEn), Permutation Entropy (PermEn) provided the most sensitive estimations in investigating the impact of MPH treatment. In detail, the considerable decrease in EEG complexity levels were observed at six cortical regions (F3, F4, P4, T3, T6, O2) with statistically significant level (p < .05). As well, PermEn provided the most meaningful associations at central lobes as follows: 1) The largeness of EEG complexity levels was moderately related to the severity of ADHD symptom detected at pre-treatment stage. 2) The percentage change in the severity of opposition as the symptom cluster was moderately reduced by the change in entropy. Conclusion: A significant decrease in entropy levels in the frontal region was detected in boys with combined type ADHD undergoing MPH treatment at resting-state mode. The changes in entropy correlated with pre-treatment general symptom severity of ADHD and conduct disorder symptom cluster severity.
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Affiliation(s)
| | | | - Serap Aydın
- 37515Hacettepe University, Sıhhiye, Ankara, Turkey
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Antagonization of monoamine reuptake transporters by agmatine improves anxiolytic and locomotive behaviors commensurate with fluoxetine and methylphenidate. BENI-SUEF UNIVERSITY JOURNAL OF BASIC AND APPLIED SCIENCES 2021. [DOI: 10.1186/s43088-021-00118-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Agmatine (AGM) is known for its protective effects including neuroprotection, nephroprotection, gastroprotection, cardioprotection, and glucoprotection. Studies have validated the neuroprotective role of AGM as antidepressant, anxiolytic, locomotive, and antipsychotic agent in psychopathologies. Fluoxetine (FLX) is the most extensively prescribed antidepressant while methylphenidate (MPD) is the most frequently prescribed psychoactive stimulant for ADHD (attention deficit hyperactivity disorder) treatment worldwide. The mechanism of action of FLX and MPD involves reuptake inhibition of serotonin and dopamine and norepinephrine at presynaptic transporters. Present study was designed to determine the safety and efficacy of AGM administration along with conventional antidepressant and psychostimulative drugs. The study also aimed to establish underlying mechanism of action of AGM at monoamine reuptake transporters.
Results
AGM significantly ameliorated locomotion in activity box and open field while anxiolytic behaviors in light/dark transition box and EPM were also improved (p<0.01). The growth and appetite of animals were enhanced along with antidepressive behavior in FST (p<0.01). Moreover, co-administration of AGM with FLX or MPD improved rats’ behaviors as compared to single AGM administration.
Conclusion
Present study determined the significant anxiolytic, locomotor, and antidepressive effects of AGM compared with FLX and MPD. The study also showed improved behaviors of rats treated with combined doses of AGM with FLX or MPD along with food intake and body weights. This study has also proposed the potential mechanism of action of AGM at monoamine receptors that may lead to inhibition of monoamine reuptake transporters that may lead to increase in 5-HT, D, and NE concentrations at synaptic level.
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Jhang CL, Lee HY, Chen JC, Liao W. Dopaminergic loss of cyclin-dependent kinase-like 5 recapitulates methylphenidate-remediable hyperlocomotion in mouse model of CDKL5 deficiency disorder. Hum Mol Genet 2021; 29:2408-2419. [PMID: 32588892 DOI: 10.1093/hmg/ddaa122] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 05/24/2020] [Accepted: 06/11/2020] [Indexed: 12/20/2022] Open
Abstract
Cyclin-dependent kinase-like 5 (CDKL5), a serine-threonine kinase encoded by an X-linked gene, is highly expressed in the mammalian forebrain. Mutations in this gene cause CDKL5 deficiency disorder, a neurodevelopmental encephalopathy characterized by early-onset seizures, motor dysfunction, and intellectual disability. We previously found that mice lacking CDKL5 exhibit hyperlocomotion and increased impulsivity, resembling the core symptoms in attention-deficit hyperactivity disorder (ADHD). Here, we report the potential neural mechanisms and treatment for hyperlocomotion induced by CDKL5 deficiency. Our results showed that loss of CDKL5 decreases the proportion of phosphorylated dopamine transporter (DAT) in the rostral striatum, leading to increased levels of extracellular dopamine and hyperlocomotion. Administration of methylphenidate (MPH), a DAT inhibitor clinically effective to improve symptoms in ADHD, significantly alleviated the hyperlocomotion phenotype in Cdkl5 null mice. In addition, the improved behavioral effects of MPH were accompanied by a region-specific restoration of phosphorylated dopamine- and cAMP-regulated phosphoprotein Mr 32 kDa, a key signaling protein for striatal motor output. Finally, mice carrying a Cdkl5 deletion selectively in DAT-expressing dopaminergic neurons, but not dopamine receptive neurons, recapitulated the hyperlocomotion phenotype found in Cdkl5 null mice. Our findings suggest that CDKL5 is essential to control locomotor behavior by regulating region-specific dopamine content and phosphorylation of dopamine signaling proteins in the striatum. The direct, as well as indirect, target proteins regulated by CDKL5 may play a key role in movement control and the therapeutic development for hyperactivity disorders.
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Affiliation(s)
- Cian-Ling Jhang
- Institute of Neuroscience, National Cheng-Chi University, Taipei 116, Taiwan
| | - Hom-Yi Lee
- Department of Psychology, Chung Shan Medical University, Taichung 402, Taiwan.,Department of Speech Language Pathology and Audiology, Chung Shan Medical University, Taichung 402, Taiwan
| | - Jin-Chung Chen
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 333, Taiwan
| | - Wenlin Liao
- Institute of Neuroscience, National Cheng-Chi University, Taipei 116, Taiwan.,Research Center for Mind, Brain and Learning, National Cheng-Chi University, Taipei 116, Taiwan
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Newman-Tancredi A, Depoortère RY, Kleven MS, Kołaczkowski M, Zimmer L. Translating biased agonists from molecules to medications: Serotonin 5-HT 1A receptor functional selectivity for CNS disorders. Pharmacol Ther 2021; 229:107937. [PMID: 34174274 DOI: 10.1016/j.pharmthera.2021.107937] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/01/2021] [Accepted: 06/17/2021] [Indexed: 12/18/2022]
Abstract
Biased agonism (or "functional selectivity") at G-protein-coupled receptors has attracted rapidly increasing interest as a means to improve discovery of more efficacious and safer pharmacotherapeutics. However, most studies are limited to in vitro tests of cellular signaling and few biased agonists have progressed to in vivo testing. As concerns 5-HT1A receptors, which exert a major control of serotonergic signaling in diverse CNS regions, study of biased agonism has previously been limited by the poor target selectivity and/or partial agonism of classically available ligands. However, a new generation of highly selective, efficacious and druggable agonists has advanced the study of biased agonism at this receptor and created new therapeutic opportunities. These novel agonists show differential properties for G-protein signaling, cellular signaling (particularly pERK), electrophysiological effects, neurotransmitter release, neuroimaging by PET and pharmacoMRI, and behavioral tests of mood, motor activity and side effects. Overall, NLX-101 (a.k.a. F15599) exhibits preferential activation of cortical and brain stem 5-HT1A receptors, whereas NLX-112 (a.k.a. befiradol or F13640) shows prominent activation of 5-HT1A autoreceptors in Raphe nuclei and in regions associated with motor control. Accordingly, NLX-101 is potently active in rodent models of depression and respiratory control, whereas NLX-112 shows promising activity in models of Parkinson's disease across several species - rat, marmoset and macaque. Moreover, NLX-112 has also been labeled with 18F to produce the first agonist PET radiopharmaceutical (known as [18F]-F13640) for investigation of the active state of 5-HT1A receptors in rodent, primate and human. The structure-functional activity relationships of biased agonists have been investigated by receptor modeling and novel compounds have been identified which exhibit increased affinity at 5-HT1A receptors and new profiles of cellular signaling bias, notably for β-arrestin recruitment versus pERK. Taken together, the data suggest that 5-HT1A receptor biased agonists constitute potentially superior pharmacological agents for treatment of CNS disorders involving serotonergic mechanisms.
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Affiliation(s)
| | | | | | | | - Luc Zimmer
- Université Claude Bernard Lyon1, Lyon, France; Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, CNRS-INSERM, France
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Zimmer L. Fundamental and clinical neuropharmacology, a terra incognita with constantly expanding frontiers. Fundam Clin Pharmacol 2021; 35:501-505. [PMID: 34013525 DOI: 10.1111/fcp.12649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Neuropharmacology is the science that studies the effects of drugs on the central nervous system. Examining the recent history of neuropharmacology allows us to identify future challenges and to project into the future. The contemporary history of neuropharmacology begins with the empirical use of psychotropic alkaloids in barbiturate preparations. Then the discovery of neuroleptics in the 1950s truly opened up the field of pharmacological science, with psychopharmacological clinical exploration in psychiatry, complemented by the contributions of neurochemists and biochemists discovering and exploring neurotransmission. These studies also contributed to the development of dopaminergic and serotonergic drugs used in neurology. The more recent period brought the advent of neuropsychopharmacology, sharing therapeutic targets in neurology and psychiatry on the one hand, and a translational research approach on the other. Moreover, the pharmacology of brain drugs is still a growing discipline in 2020. Despite emerging pharmacological concepts (biased agonists, glial targeting, epigenetic therapeutics, etc.), entire areas of brain-based therapeutics need to be renewed, particularly in psychiatry, offering great challenges to a new generation of pharmacologists and clinicians.
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Affiliation(s)
- Luc Zimmer
- Lyon Neuroscience Research Center, Université Claude Bernard Lyon 1, CRNS, INSERM, Lyon, France.,Hospices Civils de Lyon, Lyon, France.,National Institute for Nuclear Science and Technology, INSTN, Saclay, France
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10
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ADHD: Reviewing the Causes and Evaluating Solutions. J Pers Med 2021; 11:jpm11030166. [PMID: 33804365 PMCID: PMC7999417 DOI: 10.3390/jpm11030166] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/05/2021] [Accepted: 02/23/2021] [Indexed: 12/11/2022] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder in which patients present inattention, hyperactivity, and impulsivity. The etiology of this condition is diverse, including environmental factors and the presence of variants of some genes. However, a great diversity exists among patients regarding the presence of these ADHD-associated factors. Moreover, there are variations in the reported neurophysiological correlates of ADHD. ADHD is often treated pharmacologically, producing an improvement in symptomatology, albeit there are patients who are refractory to the main pharmacological treatments or present side effects to these drugs, highlighting the importance of developing other therapeutic options. Different non-pharmacological treatments are in this review addressed, finding diverse results regarding efficacy. Altogether, ADHD is associated with different etiologies, all of them producing changes in brain development, leading to the characteristic symptomatology of this condition. Given the heterogeneous etiology of ADHD, discussion is presented about the convenience of personalizing ADHD treatment, whether pharmacological or non-pharmacological, to reach an optimum effect in the majority of patients. Approaches to personalizing both pharmacological therapy and neurofeedback are presented.
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The Relationship Among Glucose Metabolism, Cerebral Blood Flow, and Functional Activity: a Hybrid PET/fMRI Study. Mol Neurobiol 2021; 58:2862-2873. [PMID: 33523358 DOI: 10.1007/s12035-021-02305-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/20/2020] [Indexed: 10/22/2022]
Abstract
18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) estimate brain activities from different aspects, including regional glucose uptake (rGU) by 18FDG-PET, regional cerebral blood flow (rCBF) by arterial spin labeling, and dynamic changes of deoxyhemoglobin by blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI). However, the relationships between them remain incompletely understood. In the current study, twenty-four subjects (14 males, 10 females) were recruited and investigated the correlation among rGU, rCBF, and BOLD fMRI-derived metrics reflecting the neural activity, including amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality (DC) by hybrid PET/fMRI. Correlation analyses were performed across subject and across space at both voxel level and region level, considering partial volume effects by adjusting for gray matter volume. Each pair of metrics showed significant across-space correlations. rGU against ReHo showed the highest mean correlation coefficients. rGU had higher correlations with three resting-state (RS) fMRI metrics than did ASL-rCBF. However, the across-subject correlations were not significant among functional modalities (rGU, rCBF, and RS-fMRI BOLD data) at either voxel level or region level even with a liberal threshold, except for significant across-subject correlation between RS-fMRI metrics (ALFF, ReHo, and DC). These comprehensive findings from hybrid PET/MR might provide complementary information to reveal the underlying mechanisms of the brain activity and open new perspective to interpret pathologic conditions.
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12
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Visual statistical learning and integration of perceptual priors are intact in attention deficit hyperactivity disorder. PLoS One 2020; 15:e0243100. [PMID: 33332378 PMCID: PMC7746270 DOI: 10.1371/journal.pone.0243100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 11/13/2020] [Indexed: 11/29/2022] Open
Abstract
Background Deficits in visual statistical learning and predictive processing could in principle explain the key characteristics of inattention and distractibility in attention deficit hyperactivity disorder (ADHD). Specifically, from a Bayesian perspective, ADHD may be associated with flatter likelihoods (increased sensory processing noise), and/or difficulties in generating or using predictions. To our knowledge, such hypotheses have never been directly tested. Methods We here test these hypotheses by evaluating whether adults diagnosed with ADHD (n = 17) differed from a control group (n = 30) in implicitly learning and using low-level perceptual priors to guide sensory processing. We used a visual statistical learning task in which participants had to estimate the direction of a cloud of coherently moving dots. Unbeknown to the participants, two of the directions were more frequently presented than the others, creating an implicit bias (prior) towards those directions. This task had previously revealed differences in other neurodevelopmental disorders, such as autistic spectrum disorder and schizophrenia. Results We found that both groups acquired the prior expectation for the most frequent directions and that these expectations substantially influenced task performance. Overall, there were no group differences in how much the priors influenced performance. However, subtle group differences were found in the influence of the prior over time. Conclusion Our findings suggest that the symptoms of inattention and hyperactivity in ADHD do not stem from broad difficulties in developing and/or using low-level perceptual priors.
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Imagerie TEP pour l’étude des répercussions fonctionnelles de la P-glycoprotéine en neuropharmacocinétique. Therapie 2020; 75:623-632. [DOI: 10.1016/j.therap.2020.02.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/03/2019] [Accepted: 02/17/2020] [Indexed: 11/20/2022]
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Al-Adawi S, Al-Naamani A, Jaju S, Al-Farsi YM, Dorvlo ASS, Al-Maashani A, Al-Adawi SSH, Moustafa AA, Al-Sibani N, Essa MM, Burke DT, Qoronfleh MW. Methylphenidate improves executive functions in patients with traumatic brain injuries: a feasibility trial via the idiographic approach. BMC Neurol 2020; 20:103. [PMID: 32192470 PMCID: PMC7081568 DOI: 10.1186/s12883-020-01663-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 02/27/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Road traffic accidents are known to be the main cause of traumatic brain injury (TBI). TBI is also a leading cause of death and disability. This study, by means of the idiographic approach (single-case experimental designs using multiple-baseline designs), has examined whether methylphenidate (MPH - trade name Ritalin) had a differential effect on cognitive measures among patients with TBI with the sequel of acute and chronic post-concussion syndromes. The effect on gender was also explored. METHODS In comparison with healthy controls, patients with TBI (acute and chronic) and accompanying mild cognitive impairment (MCI) were screened for their integrity of executive functioning. Twenty-four patients exhibiting executive dysfunction (ED) were then instituted with the pharmacological intervention methylphenidate (MPH). The methylphenidate was administered using an uncontrolled, open label design. RESULTS The administration of methylphenidate impacted ED in the TBI group but had no effect on mood. Attenuation of ED was more apparent in the chronic phases of TBI. The effect on gender was not statistically significant with regard to the observed changes. CONCLUSIONS To our knowledge, this is the first feasibility trial from the Arabian Gulf to report the performance of a TBI population with mild cognitive impairment according to the IQCODE Arabic version. This investigation confirms anecdotal observations of methylphenidate having the potential to attenuate cognitive impairment; particularly those functions that are critically involved in the integrity of executive functioning. The present feasibility trial should be followed by nomothetic studies such as those that adhere to the protocol of the randomized controlled trial. This evidence-based research is the foundation for intervention and future resource allocation by policy- or public health decision-makers.
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Affiliation(s)
- Samir Al-Adawi
- Department of Behavioural Medicine, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Aziz Al-Naamani
- Department of Behavioural Medicine, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Sanjay Jaju
- Department of Family Medicine and Public Health, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Yahya M. Al-Farsi
- Department of Family Medicine and Public Health, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Atsu S. S. Dorvlo
- Department of Mathematics and Statistics, College of Science, Sultan Qaboos University, Muscat, Oman
| | - Ali Al-Maashani
- Department of Neurosurgery, Khoula Hospital, Ministry of Health, Muscat, Oman
| | | | - Ahmed A. Moustafa
- School of Social Sciences and Psychology, Marcs Institute of Brain and Behaviour, Western Sydney University, Penrith, NSW Australia
| | - Nasser Al-Sibani
- Department of Behavioural Medicine, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Musthafa M. Essa
- Department of Food Science and Nutrition, College of Agricultural and Marine Sciences, Sultan Qaboos University, Muscat, Oman
| | - David T. Burke
- Department of Rehabilitation Medicine, Emory University School of Medicine, Atlanta, GA USA
| | - M. Walid Qoronfleh
- Research & Policy Department, World Innovation Summit for Health (WISH), Qatar Foundation, P.O. Box 5825, Doha, Qatar
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Furukawa E, da Costa RQM, Bado P, Hoefle S, Vigne P, Monteiro M, Wickens JR, Moll J, Tripp G, Mattos P. Methylphenidate modifies reward cue responses in adults with ADHD: An fMRI study. Neuropharmacology 2020; 162:107833. [DOI: 10.1016/j.neuropharm.2019.107833] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 01/01/2023]
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A comparison of efficacy between cognitive behavioral therapy (CBT) and CBT combined with medication in adults with attention-deficit/hyperactivity disorder (ADHD). Psychiatry Res 2019; 279:23-33. [PMID: 31280035 DOI: 10.1016/j.psychres.2019.06.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 12/11/2022]
Abstract
The study aimed to explore whether cognitive behavioral therapy (CBT) combined with medication is superior to CBT alone in core symptoms, emotional symptoms, self-esteem as well as social and cognitive functions of adult attention-deficit/hyperactivity disorder (ADHD) patients. Samples from a previous RCT study and outpatient participants were all included. A total of 124 patients received 12 weeks of manualized CBT sessions, either with (n = 57) or without (n = 67) medication. Efficacy variables were evaluated at baseline and each week. Mixed linear models (MLM) were used to compare differences between the two groups in all of the above domains. Within-group comparisons showed that both groups had robust improvements in core ADHD symptoms, emotional symptoms and social functional outcomes. The CBT + M group presented more domains of improvement in executive functions than the CBT group. However, comparisons between groups didn't indicate the superiority of CBT + M in core symptoms, emotional symptoms and self-esteem. Instead, the CBT group showed a greater improvement in the physical domain of the WHOQOL-BREF than the CBT + M group. This study further indicated that CBT is an effective treatment for adults with ADHD. A combination of CBT and medication presented broader improvements in executive functions, but not in clinical symptoms, than CBT alone.
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Pievsky MA, McGrath RE. Neurocognitive effects of methylphenidate in adults with attention-deficit/hyperactivity disorder: A meta-analysis. Neurosci Biobehav Rev 2018; 90:447-455. [DOI: 10.1016/j.neubiorev.2018.05.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 05/06/2018] [Accepted: 05/07/2018] [Indexed: 01/19/2023]
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Revealing the Structural Neural Circuitry of Attention Deficit Hyperactivity Disorder With Diffusion MRI: Implications for Future Diagnosis and Treatment. AJR Am J Roentgenol 2018; 210:731-733. [DOI: 10.2214/ajr.17.18983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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