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Razavinia F, Ebrahimiyan A, Faal Siahkal S, Ghazinezhad N, Abedi P. Vitamins B 9 and B 12 in children with attention deficit hyperactivity disorder (ADHD). INT J VITAM NUTR RES 2024; 94:476-484. [PMID: 38904980 DOI: 10.1024/0300-9831/a000809] [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] [Indexed: 06/22/2024]
Abstract
Background: Attention deficit hyperactivity disorder (ADHD) is a common childhood neurodevelopmental disorder that begins before age 12. Given the role of B group vitamins in cell metabolism, synthesis of nucleotides, and neurotransmitters, the present study systematically investigated the plasma levels of vitamins B9 and B12 in children with ADHD. Methods: We searched electronic databases including Web of Science, MEDLINE, EMBASE, Scopus, Iran MEDEX, Cochran database, and SID from conception to June 2023. Full-text case-control or cross-sectional studies were included in this study. Participants in the case group were children with ADHD aged 6-12 years. Review Manager Software (RevMan 5.4) was used for statistical analyses. Standardized mean differences (SMD) with 95% CIs were used to determine the differences between the two groups. Results: Six studies were included in the present meta-analysis. They included 982 children, of whom, 204 were girls and 744 were boys. The mean age of the children was 8.86±2.03 years. The level of vitamin B9 was significantly different between children with and without ADHD [SMD -0.80, 95% CI (-1.55, -0.04)]. Vitamin B12 was significantly lower in children with ADHD [SMD -0.29, 95% CI (-0.42, -0.16)]. However, due to high heterogeneity (I2 = 93%), sensitivity analysis was used, I2 fell to 21%, and significant difference was observed between the two groups [SMD -0.19, 95% CI (-0.34, -0.04)]. Conclusion: The results of this systematic review showed that the level of vitamins B9 and B12 in children with ADHD was significantly lower than that in healthy children.
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Affiliation(s)
- Fatemeh Razavinia
- Midwifery Department, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Atefeh Ebrahimiyan
- Midwifery Department, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Shahla Faal Siahkal
- Department of Midwifery, Marand Branch, Islamic Azad University, Marand, Iran
| | - Neda Ghazinezhad
- Faculty of Medical Sciences, Department of Reproductive Health and Midwifery, Tarbiat Modares University, Tehran, Iran
| | - Parvin Abedi
- Midwifery Department, Menopause Andropause Research Center, Ahvaz Jundisahpur University of Medical Sciences, Ahvaz, Iran
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Kuang J, Kafetzopoulos V, Deth R, Kocsis B. Dopamine D4 Receptor Agonist Drastically Increases Delta Activity in the Thalamic Nucleus Reuniens: Potential Role in Communication between Prefrontal Cortex and Hippocampus. Int J Mol Sci 2023; 24:15289. [PMID: 37894968 PMCID: PMC10607171 DOI: 10.3390/ijms242015289] [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: 08/30/2023] [Revised: 10/11/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Network oscillations are essential for all cognitive functions. Oscillatory deficits are well established in psychiatric diseases and are recapitulated in animal models. They are significantly and specifically affected by pharmacological interventions using psychoactive compounds. Dopamine D4 receptor (D4R) activation was shown to enhance gamma rhythm in freely moving rats and to specifically affect slow delta and theta oscillations in the urethane-anesthetized rat model. The goal of this study was to test the effect of D4R activation on slow network oscillations at delta and theta frequencies during wake states, potentially supporting enhanced functional connectivity during dopamine-induced attention and cognitive processing. Network activity was recorded in the prefrontal cortex (PFC), hippocampus (HC) and nucleus reuniens (RE) in control conditions and after injecting the D4R agonist A-412997 (3 and 5 mg/kg; systemic administration). We found that A-412997 elicited a lasting (~40 min) wake state and drastically enhanced narrow-band delta oscillations in the PFC and RE in a dose-dependent manner. It also preferentially enhanced delta synchrony over theta coupling within the PFC-RE-HC circuit, strongly strengthening PFC-RE coupling. Thus, our findings indicate that the D4R may contribute to cognitive processes, at least in part, through acting on wake delta oscillations and that the RE, providing an essential link between the PFC and HC, plays a prominent role in this mechanism.
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Affiliation(s)
- J. Kuang
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; (J.K.); (V.K.)
| | - V. Kafetzopoulos
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; (J.K.); (V.K.)
- Department of Psychiatry, Medical School, University of Ioannina, 45110 Ioannina, Greece
| | - Richard Deth
- Department of Pharmaceutical Sciences, Nova Southeastern University, Fort Lauderdale, FL 33328, USA;
| | - B. Kocsis
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; (J.K.); (V.K.)
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Dopamine Receptor Expression and the Pathogenesis of Attention-Deficit Hyperactivity Disorder: a Scoping Review of the Literature. CURRENT DEVELOPMENTAL DISORDERS REPORTS 2022. [DOI: 10.1007/s40474-022-00253-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Schrier MS, Zhang Y, Trivedi MS, Deth RC. Decreased cortical Nrf2 gene expression in autism and its relationship to thiol and cobalamin status. Biochimie 2021; 192:1-12. [PMID: 34517051 DOI: 10.1016/j.biochi.2021.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 08/02/2021] [Accepted: 09/06/2021] [Indexed: 12/13/2022]
Abstract
Nuclear factor erythroid 2-related factor 2 (Nrf2) promotes expression of a large number of antioxidant genes and multiple studies have described oxidative stress and impaired methylation in autism spectrum disorder (ASD), including decreased brain levels of methylcobalamin(III) (MeCbl). Here we report decreased expression of the Nrf2 gene (NFE2L2) in frontal cortex of ASD subjects, as well as differences in other genes involved in redox homeostasis. In pooled control and ASD correlation analyses, hydroxocobalamin(III) (OHCbl) was inversely correlated with NFE2L2 expression, while MeCbl and total cobalamin abundance were positively correlated with NFE2L2 expression. Levels of methionine, S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH) and cystathionine were positively correlated with NFE2L2 expression, while homocysteine (HCY) was negatively correlated. The relationship between Nrf2 activity and cobalamin was further supported by a bioinformatics-based comparison of cobalamin levels in different tissues with expression of a panel of 40 Nrf2-regulated genes, which yielded a strong correlation. Lastly, Nrf2-regulated gene expression was also correlated with expression of intracellular cobalamin trafficking and processing genes, such as MMADHC and MTRR. These findings highlight a previously unrecognized relationship between the antioxidant-promoting role of Nrf2 and cobalamin status, which is dysfunctional in ASD.
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Affiliation(s)
- Matthew Scott Schrier
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Yiting Zhang
- Biologics, Bristol Myers Squibb, Devens, MA, USA
| | - Malav Suchin Trivedi
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Richard Carlton Deth
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL, USA.
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Anitha A, Viswambharan V, Thanseem I, Iype M, Parakkal R, Surendran SP, Mundalil MV. Vitamins and Cognition: A Nutrigenomics Perspective. CURRENT NUTRITION & FOOD SCIENCE 2021. [DOI: 10.2174/1573401316999200901180443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The rise in the prevalence of neurodegenerative and neurodevelopmental cognitive disorders
combined with a lack of efficient therapeutic strategies has necessitated the need to develop alternate
approaches. Dietary supplements are now being considered as a complementary and alternative
medicine for cognitive impairments. Considerable evidence suggests the role of vitamins in
modulating the genetic and epigenetic factors implicated in neuropsychiatric, neurodevelopmental
and neurodegenerative disorders. In this review, we provide an overview of the implications of nutrigenomics
with reference to vitamins that are suggested to boost cognitive functions (nootropic vitamins).
Several vitamins have been found to possess antioxidant and anti-inflammatory properties
which make them potential candidates in preventing or delaying age-related neurodegeneration and
cognitive decline. Well-designed longitudinal studies are essential to examine the association between
vitamins and cognitive functions. Future studies linking nutrition with advances in neuroscience,
genomics and epigenomics would provide novel approaches to managing cognitive disorders.
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Affiliation(s)
- Ayyappan Anitha
- Department of Neurogenetics, Institute for Communicative and Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Vijitha Viswambharan
- Department of Neurogenetics, Institute for Communicative and Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Ismail Thanseem
- Department of Neurogenetics, Institute for Communicative and Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Mary Iype
- Government Medical College, Thiruvananthapuram 695 011, Kerala, India
| | - Rahna Parakkal
- Department of Neurogenetics, Institute for Communicative and Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Sumitha P. Surendran
- Department of Neurogenetics, Institute for Communicative and Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Mahesh V. Mundalil
- Department of Neurogenetics, Institute for Communicative and Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
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Methylation-related metabolic effects of D4 dopamine receptor expression and activation. Transl Psychiatry 2019; 9:295. [PMID: 31719518 PMCID: PMC6851363 DOI: 10.1038/s41398-019-0630-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 10/13/2019] [Accepted: 10/20/2019] [Indexed: 11/16/2022] Open
Abstract
D4 dopamine receptor (D4R) activation uniquely promotes methylation of plasma membrane phospholipids, utilizing folate-derived methyl groups provided by methionine synthase (MS). We evaluated the impact of D4R expression on folate-dependent phospholipid methylation (PLM) and MS activity, as well as cellular redox and methylation status, in transfected CHO cells expressing human D4R variants containing 2, 4, or 7 exon III repeats (D4.2R, D4.4R, D4.7R). Dopamine had no effect in non-transfected CHO cells, but increased PLM to a similar extent for both D4.2R- and D4.4R-expressing cells, while the maximal increase was for D4.7R was significantly lower. D4R expression in CHO cells decreased basal MS activity for all receptor subtypes and conferred dopamine-sensitive MS activity, which was greater with a higher number of repeats. Consistent with decreased MS activity, D4R expression decreased basal levels of methylation cycle intermediates methionine, S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH), as well as cysteine and glutathione (GSH). Conversely, dopamine stimulation increased GSH, SAM, and the SAM/SAH ratio, which was associated with a more than 2-fold increase in global DNA methylation. Our findings illustrate a profound influence of D4R expression and activation on MS activity, coupled with the ability of dopamine to modulate cellular redox and methylation status. These previously unrecognized signaling activities of the D4R provide a unique link between neurotransmission and metabolism.
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Yektaş Ç, Alpay M, Tufan AE. Comparison of serum B12, folate and homocysteine concentrations in children with autism spectrum disorder or attention deficit hyperactivity disorder and healthy controls. Neuropsychiatr Dis Treat 2019; 15:2213-2219. [PMID: 31496704 PMCID: PMC6689552 DOI: 10.2147/ndt.s212361] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/10/2019] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVE We aimed to investigate the serum concentrations of vitamin B12, folate and homocysteine in children diagnosed with attention deficit hyperactivity disorder (ADHD) or autism spectrum disorder (ASD) and healthy controls. MATERIALS AND METHODS Serum vitamin B12, folate and homocysteine concentrations were measured in 118 children (48 children diagnosed with ADHD, 35 children diagnosed with ASD and 35 healthy controls). Symptom severity in the ADHD and ASD groups was evaluated by the Childhood Autism Rating Scale and Turgay-DSM-IV-Based Screening and Assessment Scale for Disruptive Behavior Disorders. Multivariate analysis of covariance was used to evaluate the effects of diagnosis and gender on biochemical parameters. RESULTS The ADHD and ASD groups and the healthy controls differed significantly regarding vitamin B12 and homocysteine concentrations, but not folate levels. Patients with ASD had the lowest vitamin B12 and the highest homocysteine levels. Vitamin B12 levels correlated negatively with hyperactivity and/orimpulsivity and oppositionality symptoms in children with ADHD. There were no relationships between psychometric evaluations and laboratory measurements in children with ASD. Gender did not affect vitamin concentrations. CONCLUSION Previous studies found that vitamin B12 was reduced while homocysteine was elevated among patients with ADHD and ASDs. Our results also support those reported previously. Oppositionality and hyperactivity and/orimpulsivity may be related to vitamin B12 and homocysteine levels in children with ADHD. Further studies are required to define the role of these parameters and effects on the etiology and clinical manifestations of ASD and ADHD.
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Affiliation(s)
- Çiğdem Yektaş
- Department of Child and Adolescent Psychiatry, Düzce Üniversitesi, Düzce, Turkey
| | - Merve Alpay
- Department of Medical Biochemistry, Faculty of Medicine, Düzce Üniversitesi, Düzce, Turkey
| | - Ali Evren Tufan
- Department of Child and Adolescent Psychiatry, Acıbadem Üniversitesi Tıp Fakültesi, Istanbul, Turkey
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Voelker P, Sheese BE, Rothbart MK, Posner MI. Methylation polymorphism influences practice effects in children during attention tasks. Cogn Neurosci 2017; 8:72-84. [PMID: 27050482 PMCID: PMC5605136 DOI: 10.1080/17588928.2016.1170006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Epigenetic mechanisms mediate the influence of experience on gene expression. Methylation is a principal method for inducing epigenetic effects on DNA. In this paper, we examine alleles of the methylenetetrahydrofolate reductase (MTHFR) gene that vary enzyme activity, altering the availability of the methyl donor and thus changing the efficiency of methylation. We hypothesized that alleles of the MTHFR gene would influence behavior in an attention-related task in conjunction with genes known to influence attention. We found that seven-year-old children homozygous for the C allele of MTHFR in interaction with the catechol O-methyltransferase (COMT) gene showed greater improvement in overall reaction time (RT) and in conflict resolution with practice on the Attention Network Test (ANT). This finding indicates that methylation may operate on or through genes that influence executive network operation. However, MTHFR T allele carriers showed faster overall RT and conflict resolution. Some children showed an initial improvement in ANT RT followed by a decline in performance, and we found that alleles of the dopamine beta-hydroxylase (DBH) gene were related to this performance decline. These results suggest a genetic dissociation between improvement while learning a skill and reduction in performance with continued practice.
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Affiliation(s)
| | - Brad E Sheese
- b Psychology , Illinois Wesleyan University , Bloomington , USA
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Schrier MS, Trivedi MS, Deth RC. Redox-Related Epigenetic Mechanisms in Glioblastoma: Nuclear Factor (Erythroid-Derived 2)-Like 2, Cobalamin, and Dopamine Receptor Subtype 4. Front Oncol 2017; 7:46. [PMID: 28424758 PMCID: PMC5371596 DOI: 10.3389/fonc.2017.00046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/06/2017] [Indexed: 12/16/2022] Open
Abstract
Glioblastoma is an exceptionally difficult cancer to treat. Cancer is universally marked by epigenetic changes, which play key roles in sustaining a malignant phenotype, in addition to disease progression and patient survival. Studies have shown strong links between the cellular redox state and epigenetics. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a redox-sensitive transcription factor that upregulates endogenous antioxidant production, and is aberrantly expressed in many cancers, including glioblastoma. Methylation of DNA and histones provides a mode of epigenetic regulation, and cobalamin-dependent reactions link the redox state to methylation. Antagonists of dopamine receptor subtype 4 (D4 receptor) were recently shown to restrict glioblastoma stem cell growth by downregulating trophic signaling, resulting in inhibition of functional autophagy. In addition to stimulating glioblastoma stem cell growth, D4 receptors have the unique ability to catalyze cobalamin-dependent phospholipid methylation. Therefore, D4 receptors represent an important node in a molecular reflex pathway involving Nrf2 and cobalamin, operating in conjunction with redox status and methyl group donor availability. In this article, we describe the redox-related effects of Nrf2, cobalamin metabolism, and the D4 receptor on the regulation of the epigenetic state in glioblastoma.
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Affiliation(s)
- Matthew Scott Schrier
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Malav Suchin Trivedi
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Richard Carlton Deth
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL, USA
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Krucoff MO, Rahimpour S, Slutzky MW, Edgerton VR, Turner DA. Enhancing Nervous System Recovery through Neurobiologics, Neural Interface Training, and Neurorehabilitation. Front Neurosci 2016; 10:584. [PMID: 28082858 PMCID: PMC5186786 DOI: 10.3389/fnins.2016.00584] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 12/06/2016] [Indexed: 12/21/2022] Open
Abstract
After an initial period of recovery, human neurological injury has long been thought to be static. In order to improve quality of life for those suffering from stroke, spinal cord injury, or traumatic brain injury, researchers have been working to restore the nervous system and reduce neurological deficits through a number of mechanisms. For example, neurobiologists have been identifying and manipulating components of the intra- and extracellular milieu to alter the regenerative potential of neurons, neuro-engineers have been producing brain-machine and neural interfaces that circumvent lesions to restore functionality, and neurorehabilitation experts have been developing new ways to revitalize the nervous system even in chronic disease. While each of these areas holds promise, their individual paths to clinical relevance remain difficult. Nonetheless, these methods are now able to synergistically enhance recovery of native motor function to levels which were previously believed to be impossible. Furthermore, such recovery can even persist after training, and for the first time there is evidence of functional axonal regrowth and rewiring in the central nervous system of animal models. To attain this type of regeneration, rehabilitation paradigms that pair cortically-based intent with activation of affected circuits and positive neurofeedback appear to be required-a phenomenon which raises new and far reaching questions about the underlying relationship between conscious action and neural repair. For this reason, we argue that multi-modal therapy will be necessary to facilitate a truly robust recovery, and that the success of investigational microscopic techniques may depend on their integration into macroscopic frameworks that include task-based neurorehabilitation. We further identify critical components of future neural repair strategies and explore the most updated knowledge, progress, and challenges in the fields of cellular neuronal repair, neural interfacing, and neurorehabilitation, all with the goal of better understanding neurological injury and how to improve recovery.
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Affiliation(s)
- Max O Krucoff
- Department of Neurosurgery, Duke University Medical Center Durham, NC, USA
| | - Shervin Rahimpour
- Department of Neurosurgery, Duke University Medical Center Durham, NC, USA
| | - Marc W Slutzky
- Department of Physiology, Feinberg School of Medicine, Northwestern UniversityChicago, IL, USA; Department of Neurology, Feinberg School of Medicine, Northwestern UniversityChicago, IL, USA
| | - V Reggie Edgerton
- Department of Integrative Biology and Physiology, University of California, Los Angeles Los Angeles, CA, USA
| | - Dennis A Turner
- Department of Neurosurgery, Duke University Medical CenterDurham, NC, USA; Department of Neurobiology, Duke University Medical CenterDurham, NC, USA; Research and Surgery Services, Durham Veterans Affairs Medical CenterDurham, NC, USA
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Zhang Y, Hodgson NW, Trivedi MS, Abdolmaleky HM, Fournier M, Cuenod M, Do KQ, Deth RC. Decreased Brain Levels of Vitamin B12 in Aging, Autism and Schizophrenia. PLoS One 2016; 11:e0146797. [PMID: 26799654 PMCID: PMC4723262 DOI: 10.1371/journal.pone.0146797] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 12/22/2015] [Indexed: 12/21/2022] Open
Abstract
Many studies indicate a crucial role for the vitamin B12 and folate-dependent enzyme methionine synthase (MS) in brain development and function, but vitamin B12 status in the brain across the lifespan has not been previously investigated. Vitamin B12 (cobalamin, Cbl) exists in multiple forms, including methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl), serving as cofactors for MS and methylmalonylCoA mutase, respectively. We measured levels of five Cbl species in postmortem human frontal cortex of 43 control subjects, from 19 weeks of fetal development through 80 years of age, and 12 autistic and 9 schizophrenic subjects. Total Cbl was significantly lower in older control subjects (> 60 yrs of age), primarily reflecting a >10-fold age-dependent decline in the level of MeCbl. Levels of inactive cyanocobalamin (CNCbl) were remarkably higher in fetal brain samples. In both autistic and schizophrenic subjects MeCbl and AdoCbl levels were more than 3-fold lower than age-matched controls. In autistic subjects lower MeCbl was associated with decreased MS activity and elevated levels of its substrate homocysteine (HCY). Low levels of the antioxidant glutathione (GSH) have been linked to both autism and schizophrenia, and both total Cbl and MeCbl levels were decreased in glutamate-cysteine ligase modulatory subunit knockout (GCLM-KO) mice, which exhibit low GSH levels. Thus our findings reveal a previously unrecognized decrease in brain vitamin B12 status across the lifespan that may reflect an adaptation to increasing antioxidant demand, while accelerated deficits due to GSH deficiency may contribute to neurodevelopmental and neuropsychiatric disorders.
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Affiliation(s)
- Yiting Zhang
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, United States of America
| | - Nathaniel W. Hodgson
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, United States of America
- Department of Surgery, Laboratory of Nutrition and Metabolism at BIDMC, Harvard Medical School, Boston, MA, 02215, United States of America
| | - Malav S. Trivedi
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, United States of America
- Department of Pharmaceutical Sciences, Nova Southeastern University College of Pharmacy, Fort Lauderdale, FL, 33328, United States of America
| | - Hamid M. Abdolmaleky
- Department of Medicine (Biomedical Genetics Section), Genetics & Genomics, Boston University School of Medicine, Boston, MA, 02118, United States of America
| | - Margot Fournier
- Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Lausanne, Switzerland
| | - Michel Cuenod
- Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Lausanne, Switzerland
| | - Kim Quang Do
- Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Lausanne, Switzerland
| | - Richard C. Deth
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, United States of America
- Department of Pharmaceutical Sciences, Nova Southeastern University College of Pharmacy, Fort Lauderdale, FL, 33328, United States of America
- * E-mail:
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Kern JK, Geier DA, Sykes LK, Geier MR, Deth RC. Are ASD and ADHD a Continuum? A Comparison of Pathophysiological Similarities Between the Disorders. J Atten Disord 2015; 19:805-27. [PMID: 23074304 DOI: 10.1177/1087054712459886] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE The objective of this study was to review and compare the similarities between autism spectrum disorder (ASD) and ADHD with regard to symptomatology, neurological deficits, metabolic and endocrine-related conditions, and brain pathology. METHOD A comprehensive review of the relevant research literature was carried out. RESULTS A number of important similarities between ASD and ADHD were identified, including recent increases in prevalence, male-biased incidence, shared involvement of sensory processing, motor and impulse control, abnormal patterns of neural connectivity, and sleep disturbances. Studies suggest involvement of androgen metabolism, impaired methylation, and heavy metal toxicity as possible contributing factors for both disorders. CONCLUSION ASD and ADHD share a number of features and pathophysiological conditions, which suggests that the two disorders may be a continuum and have a common origin.
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Affiliation(s)
- Janet K Kern
- Institute of Chronic Illnesses, Inc., Silver Spring, MD, USA University of Texas Southwestern Medical Center at Dallas, TX, USA
| | - David A Geier
- Institute of Chronic Illnesses, Inc., Silver Spring, MD, USA
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Steullet P, Cabungcal JH, Cuénod M, Do KQ. Fast oscillatory activity in the anterior cingulate cortex: dopaminergic modulation and effect of perineuronal net loss. Front Cell Neurosci 2014; 8:244. [PMID: 25191228 PMCID: PMC4139002 DOI: 10.3389/fncel.2014.00244] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 08/01/2014] [Indexed: 11/23/2022] Open
Abstract
Dopamine release in the prefrontal cortex plays a critical role in cognitive function such as working memory, attention and planning. Dopamine exerts complex modulation on excitability of pyramidal neurons and interneurons, and regulates excitatory and inhibitory synaptic transmission. Because of the complexity of this modulation, it is difficult to fully comprehend the effect of dopamine on neuronal network activity. In this study, we investigated the effect of dopamine on local high-frequency oscillatory neuronal activity (in β band) in slices of the mouse anterior cingulate cortex (ACC). We found that dopamine enhanced the power of these oscillations induced by kainate and carbachol, but did not affect their peak frequency. Activation of D2R and in a lesser degree D1R increased the oscillation power, while activation of D4R had no effect. These high-frequency oscillations in the ACC relied on both phasic inhibitory and excitatory transmission and functional gap junctions. Thus, dopamine released in the ACC promotes high-frequency synchronized local cortical activity which is known to favor information transfer, fast selection and binding of distributed neuronal responses. Finally, the power of these oscillations was significantly enhanced after degradation of the perineuronal nets (PNNs) enwrapping most parvalbumin interneurons. This study provides new insights for a better understanding of the abnormal prefrontal gamma activity in schizophrenia (SZ) patients who display prefrontal anomalies of both the dopaminergic system and the PNNs.
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Affiliation(s)
- Pascal Steullet
- Department of Psychiatry, Center of Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois and University of Lausanne Prilly-Lausanne, Switzerland
| | - Jan-Harry Cabungcal
- Department of Psychiatry, Center of Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois and University of Lausanne Prilly-Lausanne, Switzerland
| | - Michel Cuénod
- Department of Psychiatry, Center of Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois and University of Lausanne Prilly-Lausanne, Switzerland
| | - Kim Q Do
- Department of Psychiatry, Center of Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois and University of Lausanne Prilly-Lausanne, Switzerland
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Saha T, Dutta S, Rajamma U, Sinha S, Mukhopadhyay K. A pilot study on the contribution of folate gene variants in the cognitive function of ADHD probands. Neurochem Res 2014; 39:2058-67. [PMID: 25079255 DOI: 10.1007/s11064-014-1393-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 07/15/2014] [Accepted: 07/17/2014] [Indexed: 11/28/2022]
Abstract
Genetic abnormalities in components important for the folate cycle confer risk for various disorders since adequate folate turnover is necessary for normal methylation, gene expression and chromosome structure. However, the system has rarely been studied in children diagnosed with attention deficit hyperactivity disorder (ADHD). We hypothesized that ADHD related cognitive deficit could be attributed to abnormalities in the folate cycle and explored functional single nucleotide polymorphisms in methylenetetrahydrofolate dehydrogenase (rs2236225), reduced folate carrier (rs1051266), and methylenetetrahydrofolate reductase (rs1801131 and rs1801133) in families with ADHD probands (N = 185) and ethnically matched controls (N = 216) recruited following the DSM-IV. After obtaining informed written consent for participation, peripheral blood was collected for genomic DNA isolation and PCR-based analysis of target sites. Data obtained was analyzed by UNPHASED. Interaction between sites was analyzed by the multi dimensionality reduction (MDR) program. Genotypic frequencies of the Indian population were strikingly different from other ethnic groups. rs1801133 "T" allele showed biased transmission in female probands (p < 0.05). Significant difference in genotypic frequencies for female probands was also noticed. rs1801131 and rs1801133 showed an association with low intelligence quotient (IQ). MDR analysis exhibited independent effects and contribution of these sites to IQ, thus indicating a role of these genes in ADHD related cognitive deficit.
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Affiliation(s)
- T Saha
- Manovikas Biomedical Research and Diagnostic Centre, 482, Madudah, Plot I-24, Sec.-J, E.M. Bypass, Kolkata, 700107, India
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15
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Furth KE, Mastwal S, Wang KH, Buonanno A, Vullhorst D. Dopamine, cognitive function, and gamma oscillations: role of D4 receptors. Front Cell Neurosci 2013; 7:102. [PMID: 23847468 PMCID: PMC3698457 DOI: 10.3389/fncel.2013.00102] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 06/11/2013] [Indexed: 12/29/2022] Open
Abstract
Cognitive deficits in individuals with schizophrenia (SCZ) are considered core symptoms of this disorder, and can manifest at the prodromal stage. Antipsychotics ameliorate positive symptoms but only modestly improve cognitive symptoms. The lack of treatments that improve cognitive abilities currently represents a major obstacle in developing more effective therapeutic strategies for this debilitating disorder. While D4 receptor (D4R)-specific antagonists are ineffective in the treatment of positive symptoms, animal studies suggest that D4R drugs can improve cognitive deficits. Moreover, recent work from our group suggests that D4Rs synergize with the neuregulin/ErbB4 signaling pathway, genetically identified as risk factors for SCZ, in parvalbumin (PV)-expressing interneurons to modulate gamma oscillations. These high-frequency network oscillations correlate with attention and increase during cognitive tasks in healthy subjects, and this correlation is attenuated in affected individuals. This finding, along with other observations indicating impaired GABAergic function, has led to the idea that abnormal neural activity in the prefrontal cortex (PFC) in individuals with SCZ reflects a perturbation in the balance of excitation and inhibition. Here we review the current state of knowledge of D4R functions in the PFC and hippocampus, two major brain areas implicated in SCZ. Special emphasis is given to studies focusing on the potential role of D4Rs in modulating GABAergic transmission and to an emerging concept of a close synergistic relationship between dopamine/D4R and neuregulin/ErbB4 signaling pathways that tunes the activity of PV interneurons to regulate gamma frequency network oscillations and potentially cognitive processes.
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Affiliation(s)
- Katrina E Furth
- Section on Molecular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health Bethesda, MD, USA ; Graduate Program for Neuroscience, Boston University Boston, MA, USA
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Spellicy CJ, Northrup H, Fletcher JM, Cirino PT, Dennis M, Morrison AC, Martinez CA, Au KS. Folate metabolism gene 5,10-methylenetetrahydrofolate reductase (MTHFR) is associated with ADHD in myelomeningocele patients. PLoS One 2012; 7:e51330. [PMID: 23227261 PMCID: PMC3515551 DOI: 10.1371/journal.pone.0051330] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 11/07/2012] [Indexed: 02/06/2023] Open
Abstract
The objective of this study was to examine the relation between the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene and behaviors related to attention- deficit/hyperactivity disorder (ADHD) in individuals with myelomeningocele. The rationale for the study was twofold: folate metabolizing genes, (e.g. MTHFR), are important not only in the etiology of neural tube defects but are also critical to cognitive function; and individuals with myelomeningocele have an elevated incidence of ADHD. Here, we tested 478 individuals with myelomeningocele for attention-deficit hyperactivity disorder behavior using the Swanson Nolan Achenbach Pelham-IV ADHD rating scale. Myelomeningocele participants in this group for whom DNAs were available were genotyped for seven single nucleotide polymorphisms (SNPs) in the MTHFR gene. The SNPs were evaluated for an association with manifestation of the ADHD phenotype in children with myelomeningocele. The data show that 28.7% of myelomeningocele participants exhibit rating scale elevations consistent with ADHD; of these 70.1% had scores consistent with the predominantly inattentive subtype. In addition, we also show a positive association between the SNP rs4846049 in the 3'-untranslated region of the MTHFR gene and the attention-deficit hyperactivity disorder phenotype in myelomeningocele participants. These results lend further support to the finding that behavior related to ADHD is more prevalent in patients with myelomeningocele than in the general population. These data also indicate the potential importance of the MTHFR gene in the etiology of the ADHD phenotype.
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Affiliation(s)
- Catherine J. Spellicy
- Department of Pediatrics, University of Texas Medical School at Houston, The University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Hope Northrup
- Department of Pediatrics, University of Texas Medical School at Houston, The University of Texas Health Science Center at Houston, Houston, Texas, United States of America
- Shriners Hospital for Children, Houston, Texas, United States of America
| | - Jack M. Fletcher
- Department of Psychology, University of Houston, Houston, Texas, United States of America
| | - Paul T. Cirino
- Department of Psychology and Texas Institute for Measurement, Evaluation, and Statistics (TIMES), University of Houston, Houston, Texas, United States of America
| | - Maureen Dennis
- Department of Surgery, University of Toronto, and Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Canada
| | - Alanna C. Morrison
- Human Genetics Center, Division of Epidemiology, Human Genetics and Environmental Science, School of Public Health, University of Texas Health Sciences Center at Houston, Houston, Texas, United States of America
| | - Carla A. Martinez
- Department of Obstetrics and Gynecology, Texas Tech University Health Science Center, El Paso, Texas, United States of America
| | - Kit Sing Au
- Department of Pediatrics, University of Texas Medical School at Houston, The University of Texas Health Science Center at Houston, Houston, Texas, United States of America
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Smythies J, Edelstein L, Ramachandran V. Hypotheses relating to the function of the claustrum. Front Integr Neurosci 2012; 6:53. [PMID: 22876222 PMCID: PMC3410410 DOI: 10.3389/fnint.2012.00053] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 07/12/2012] [Indexed: 11/13/2022] Open
Abstract
This paper present a new hypothesis as to the function of the claustrum. Our basic premise is that the claustrum functions as a detector and integrator of synchrony in the axonal trains in its afferent inputs. In the first place an unexpected stimulus sets up a processed signal to the sensory cortex that initiates a focus of synchronized gamma oscillations therein. This focus may then interact with a general alerting signal conveyed from the reticular formation via cholinergic mechanisms, and with other salient activations set up by the stimulus in other sensory pathways that are relayed to the cortex. This activity is relayed from the cortex to the claustrum, which then processes these several inputs by means of multiple competitive intraclaustral synchronized oscillations at different frequencies. Finally it modulates the synchronized outputs that the claustrum distributes to most cortical and many subcortical structures, including the motor cortex. In this way, during multicenter perceptual and cognitive operations, reverberating claustro-cortical loops potentiate weak intracortical synchronizations by means of connected strong intraclaustral synchronizations. These may also occur without a salient stimulus. By this mechanism, the claustrum may play a strong role in the control of interactive processes in different parts of the brain, and in the control of voluntary behavior. These may include the neural correlates of consciousness. We also consider the role of GABAergic mechanisms and deafferentation plasticity.
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Affiliation(s)
- John Smythies
- Center for Brain and Cognition, University of California San Diego, La Jolla CA, USA
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Prenatal and Postnatal Epigenetic Programming: Implications for GI, Immune, and Neuronal Function in Autism. AUTISM RESEARCH AND TREATMENT 2012; 2012:190930. [PMID: 22934169 PMCID: PMC3420412 DOI: 10.1155/2012/190930] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 05/03/2012] [Indexed: 12/13/2022]
Abstract
Although autism is first and foremost a disorder of the central nervous system, comorbid dysfunction of the gastrointestinal (GI) and immune systems is common, suggesting that all three systems may be affected by common molecular mechanisms. Substantial systemic deficits in the antioxidant glutathione and its precursor, cysteine, have been documented in autism in association with oxidative stress and impaired methylation. DNA and histone methylation provide epigenetic regulation of gene expression during prenatal and postnatal development. Prenatal epigenetic programming (PrEP) can be affected by the maternal metabolic and nutritional environment, whereas postnatal epigenetic programming (PEP) importantly depends upon nutritional support provided through the GI tract. Cysteine absorption from the GI tract is a crucial determinant of antioxidant capacity, and systemic deficits of glutathione and cysteine in autism are likely to reflect impaired cysteine absorption. Excitatory amino acid transporter 3 (EAAT3) provides cysteine uptake for GI epithelial, neuronal, and immune cells, and its activity is decreased during oxidative stress. Based upon these observations, we propose that neurodevelopmental, GI, and immune aspects of autism each reflect manifestations of inadequate antioxidant capacity, secondary to impaired cysteine uptake by the GI tract. Genetic and environmental factors that adversely affect antioxidant capacity can disrupt PrEP and/or PEP, increasing vulnerability to autism.
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Wu J, Xiao H, Sun H, Zou L, Zhu LQ. Role of dopamine receptors in ADHD: a systematic meta-analysis. Mol Neurobiol 2012; 45:605-20. [PMID: 22610946 DOI: 10.1007/s12035-012-8278-5] [Citation(s) in RCA: 171] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2012] [Accepted: 05/07/2012] [Indexed: 01/11/2023]
Abstract
The dopaminergic system plays a pivotal role in the central nervous system via its five diverse receptors (D1-D5). Dysfunction of dopaminergic system is implicated in many neuropsychological diseases, including attention deficit hyperactivity disorder (ADHD), a common mental disorder that prevalent in childhood. Understanding the relationship of five different dopamine (DA) receptors with ADHD will help us to elucidate different roles of these receptors and to develop therapeutic approaches of ADHD. This review summarized the ongoing research of DA receptor genes in ADHD pathogenesis and gathered the past published data with meta-analysis and revealed the high risk of DRD5, DRD2, and DRD4 polymorphisms in ADHD.
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Affiliation(s)
- Jing Wu
- Department of Epidemiology and Biostatistics and Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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20
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Genetics of dopamine receptors and drug addiction. Hum Genet 2012; 131:803-22. [PMID: 22350797 DOI: 10.1007/s00439-012-1145-7] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 02/04/2012] [Indexed: 01/18/2023]
Abstract
Dopamine plays a key role in reward behavior, yet the association of drug dependence as a chronic, relapsing disorder with the genes encoding the various dopaminergic receptor subtypes remains difficult to delineate. In the context of subsequent genome-wide association (GWAS) research and post-GWAS investigations, we summarize the novel data that link genes encoding molecules involved in the dopaminergic system (dopamine receptors, transporter and enzymes in charge of its metabolism) to drug addiction. Recent reports indicate that the heritability of drug addiction should be high enough to allow a significant role for a specific set of genes, and the available genetic studies, which might not be already conclusive because of the heterogeneity of designs, methods and recruited samples, should support the idea of a significant role of at least one gene related to dopaminergic system. Evolutionary changes in primates and non-primate animals of genes coding for molecules involved in dopaminergic system highlight why addictive disorders are mainly limited to humans. Restricting the analyses to more specific intermediate phenotypes (or endophenotypes) such as attention allocation, stress reactivity, novelty seeking, behavioral disinhibition and impulsivity, instead of the broad addictive disorder concept can be instrumental to identify novel genes associated with these traits in the context of genome-wide studies.
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Ursino M, Cuppini C, Magosso E. An integrated neural model of semantic memory, lexical retrieval and category formation, based on a distributed feature representation. Cogn Neurodyn 2011; 5:183-207. [PMID: 22654990 DOI: 10.1007/s11571-011-9154-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 01/13/2011] [Accepted: 03/09/2011] [Indexed: 01/03/2023] Open
Abstract
This work presents a connectionist model of the semantic-lexical system. Model assumes that the lexical and semantic aspects of language are memorized in two distinct stores, and are then linked together on the basis of previous experience, using physiological learning mechanisms. Particular characteristics of the model are: (1) the semantic aspects of an object are described by a collection of features, whose number may vary between objects. (2) Individual features are topologically organized to implement a similarity principle. (3) Gamma-band synchronization is used to segment different objects simultaneously. (4) The model is able to simulate the formation of categories, assuming that objects belong to the same category if they share some features. (5) Homosynaptic potentiation and homosynaptic depression are used within the semantic network, to create an asymmetric pattern of synapses; this allows a different role to be assigned to shared and distinctive features during object reconstruction. (6) Features which frequently occurred together, and the corresponding word-forms, become linked via reciprocal excitatory synapses. (7) Features in the semantic network tend to inhibit words not associated with them during the previous learning phase. Simulations show that, after learning, presentation of a cue can evoke the overall object and the corresponding word in the lexical area. Word presentation, in turn, activates the corresponding features in the sensory-motor areas, recreating the same conditions occurred during learning, according to a grounded cognition viewpoint. Several words and their conceptual description can coexist in the lexical-semantic system exploiting gamma-band time division. Schematic exempla are shown, to illustrate the possibility to distinguish between words representing a category, and words representing individual members and to evaluate the role of gamma-band synchronization in priming. Finally, the model is used to simulate patients with focalized lesions, assuming a damage of synaptic strength in specific feature areas. Results are critically discussed in view of future model extensions and application to real objects. The model represents an original effort to incorporate many basic ideas, found in recent conceptual theories, within a single quantitative scaffold.
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Affiliation(s)
- Mauro Ursino
- Department of Electronics, Computer Science and Systems, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy
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Rondou P, Haegeman G, Van Craenenbroeck K. The dopamine D4 receptor: biochemical and signalling properties. Cell Mol Life Sci 2010; 67:1971-86. [PMID: 20165900 PMCID: PMC11115718 DOI: 10.1007/s00018-010-0293-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 01/19/2010] [Accepted: 01/26/2010] [Indexed: 01/20/2023]
Abstract
Dopamine is an important neurotransmitter that regulates several key functions in the brain, such as motor output, motivation and reward, learning and memory, and endocrine regulation. Dopamine does not mediate fast synaptic transmission, but rather modulates it by triggering slow-acting effects through the activation of dopamine receptors, which belong to the G-protein-coupled receptor superfamily. Besides activating different effectors through G-protein coupling, dopamine receptors also signal through interaction with a variety of proteins, collectively termed dopamine receptor-interacting proteins. We focus on the dopamine D4 receptor, which contains an important polymorphism in its third intracellular loop. This polymorphism has been the subject of numerous studies investigating links with several brain disorders, such as attention-deficit hyperactivity disorder and schizophrenia. We provide an overview of the structure, signalling properties and regulation of dopamine D4 receptors, and briefly discuss their physiological and pathophysiological role in the brain.
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Affiliation(s)
- Pieter Rondou
- Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Ghent University (UGent), K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
- Present Address: Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Medical Research Building, De Pintelaan 185, 9000 Ghent, Belgium
| | - Guy Haegeman
- Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Ghent University (UGent), K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Kathleen Van Craenenbroeck
- Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Ghent University (UGent), K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
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Ursino M, Magosso E, Cuppini C. Recognition of Abstract Objects Via Neural Oscillators: Interaction Among Topological Organization, Associative Memory and Gamma Band Synchronization. ACTA ACUST UNITED AC 2009; 20:316-35. [PMID: 19171515 DOI: 10.1109/tnn.2008.2006326] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mauro Ursino
- Department of Electronics, Computer Science and Systems, University of Bologna, I-40136 Bologna, Italy.
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