A Guidotti

University of Illinois at Chicago, Chicago, Illinois, United States

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Publications (452)2454.49 Total impact

  • F. Matrisciano · I. Panaccione · E. Dong · D.R. Grayson · A. Guidotti ·
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    ABSTRACT: The term epigenetic commonly refers to stable, environment-depending changes in genes expression that occur without altering the underlying DNA sequence. Epigenetic mechanisms are fundamental for normal development and maintenance of tissue-specifi c gene expression. Abnormalities in epigenetic processes can lead to abnormal gene function and the development of diseases. Recent evidences suggest that several diseases and behavioral disorders result from defects in gene function. Cancer, and other diseases such as autoimmune disease, asthma, type 2 diabetes, metabolic disorders, neuropsychiatric disorders, autism, display aberrant gene expression. A number of compounds targeting enzymes involved in histone acetylation, histone methylation, and DNA methylation have been developed as epigenetic drugs, with some efficacy shown in hematological malignancies and solid tumors. Recently researchers are focusing on finding new epigenetic targets for the development of new molecules for the treatment of different CNS disorders such as autism and schizophrenia targeting specific enzymes that play an important role in gene expression and function.
    Neuromethods 01/2016; 105:3-18. DOI:10.1007/978-1-4939-2754-8_1
  • Marie Anaïs Labouesse · Erbo Dong · Dennis Grayson · Alessandro Guidotti · Urs Meyer ·
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    ABSTRACT: Maternal infection during pregnancy increases the risk of neurodevelopmental disorders in the offspring. In addition to its influence on other neuronal systems, this early-life environmental adversity has been shown to negatively affect cortical γ-aminobutyric acid (GABA) functions in adult life, including impaired prefrontal expression of enzymes required for GABA synthesis. The underlying molecular processes, however, remain largely unknown. In the present study, we explored whether epigenetic modifications represent a mechanism whereby maternal infection during pregnancy can induce such GABAergic impairments in the offspring. We used an established mouse model of prenatal immune challenge that is based on maternal treatment with the viral mimetic poly(I:C). We found that prenatal immune activation increased prefrontal levels of 5-methylated cytosines (5 mC) and 5-hydroxymethylated cytosines (5 hmC) in the promoter region of GAD1, which encodes the 67-kDa isoform of the GABA-synthesizing enzyme glutamic acid decarboxylase (GAD67). The early-life challenge also increased 5 mC levels at the promoter region of GAD2, which encodes the 65-kDa GAD isoform (GAD65). These effects were accompanied by elevated GAD1 and GAD2 promoter binding of methyl CpG-binding protein 2 (MeCP2) and by reduced GAD67 and GAD65 mRNA expression. Moreover, the epigenetic modifications at the GAD1 promoter correlated with prenatal infection-induced impairments in working memory and social interaction. Our study thus highlights that hypermethylation of GAD1 and GAD2 promoters may be an important molecular mechanism linking prenatal infection to presynaptic GABAergic impairments and associated behavioral and cognitive abnormalities in the offspring.
    Epigenetics: official journal of the DNA Methylation Society 11/2015; DOI:10.1080/15592294.2015.1114202 · 4.78 Impact Factor
  • Dennis R Grayson · Alessandro Guidotti ·
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    ABSTRACT: Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that is characterized by a wide range of cognitive and behavioral abnormalities. Genetic research has identified large numbers of genes that contribute to ASD phenotypes. There is compelling evidence that environmental factors contribute to ASD through influences that differentially impact the brain through epigenetic mechanisms. Both genetic mutations and epigenetic influences alter gene expression in different cell types of the brain. Mutations impact the expression of large numbers of genes and also have downstream consequences depending on specific pathways associated with the mutation. Environmental factors impact the expression of sets of genes by altering methylation/hydroxymethylation patterns, local histone modification patterns and chromatin remodeling. Herein, we discuss recent developments in the research of ASD with a focus on epigenetic pathways as a complement to current genetic screening.
    Epigenomics 11/2015; DOI:10.2217/epi.15.92 · 4.65 Impact Factor
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    ABSTRACT: In nondividing neurons examine the role of Gadd45b in active 5-methylcytosine (5MC) and 5-hydroxymethylcytosine (5HMC) removal at a gene promoter highly implicated in mental illnesses and cognition, Bdnf. Mouse primary cortical neuronal cultures with and without Gadd45b siRNA transfection were treated with N-methyl-d-aspartate (NMDA). Expression changes of genes reportedly involved in DNA demethylation, Bdnf mRNA and protein and 5MC and 5HMC at Bdnf promoters were measured. Gadd45b siRNA transfection in neurons abolishes the NMDA-induced increase in Bdnf IXa mRNA and reductions in 5MC and 5HMC at the Bdnf IXa promoter. These results contribute to our understanding of DNA demethylation mechanisms in neurons, and its role in regulating NMDA responsive genes implicated in mental illnesses.
    Epigenomics 06/2015; 7(4):567-79. DOI:10.2217/epi.15.12 · 4.65 Impact Factor
  • E Dong · W B Ruzicka · D R Grayson · A Guidotti ·
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    ABSTRACT: The down regulation of glutamic acid decarboxylase67 (GAD1), reelin (RELN), and BDNF expression in brain of schizophrenia (SZ) and bipolar (BP) disorder patients is associated with overexpression of DNA methyltransferase1 (DNMT1) and ten-eleven translocase methylcytosine dioxygenase1 (TET1). DNMT1 and TET1 belong to families of enzymes that methylate and hydroxymethylate cytosines located proximal to and within cytosine phosphodiester guanine (CpG) islands of many gene promoters, respectively. Altered promoter methylation may be one mechanism underlying the down-regulation of GABAergic and glutamatergic gene expression. However, recent reports suggest that both DNMT1 and TET1 directly bind to unmethylated CpG rich promoters through their respective Zinc Finger (ZF-CXXC) domains. We report here, that the binding of DNMT1 to GABAergic (GAD1, RELN) and glutamatergic (BDNF-IX) promoters is increased in SZ and BP disorder patients and this increase does not necessarily correlate with enrichment in promoter methylation. The increased DNMT1 binding to these promoter regions is detected in the cortex but not in the cerebellum of SZ and BP disorder patients, suggesting a brain region and neuron specific dependent mechanism. Increased binding of DNMT1 positively correlates with increased expression of DNMT1 and with increased binding of MBD2. In contrast, the binding of TET1 to RELN, GAD1 and BDNF-IX promoters failed to change. These data are consistent with the hypothesis that the down-regulation of specific GABAergic and glutamatergic genes in SZ and BP disorder patients may be mediated, at least in part, by a brain region specific and neuronal-activity dependent DNMT1 action that is likely independent of its DNA methylation activity. Copyright © 2014. Published by Elsevier B.V.
    Schizophrenia Research 12/2014; 167(1). DOI:10.1016/j.schres.2014.10.030 · 3.92 Impact Factor
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    Alessandro Guidotti · Erbo Dong · Patricia Tueting · Dennis R Grayson ·
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    ABSTRACT: Based on postmortem brain studies, our overarching epigenetic hypothesis is that chronic schizophrenia (SZ) is a psychopathological condition involving dysregulation of the dynamic equilibrium among DNA methylation/demethylation network components and the expression of SZ target genes, including GABAergic and glutamatergic genes. SZ has a natural course, starting with a prodromal phase, a first episode that occurs in adolescents or in young adults, and later deterioration over the adult years. Hence, the epigenetic status at each neurodevelopmental stage of the disease cannot be studied just in postmortem brain of chronic SZ patients, but requires the use of neurodevelopmental animal models. We have directed the focus of our research toward studying the epigenetic signature of the SZ brain in the offspring of dams stressed during pregnancy (PRS mice). Adult PRS mice have behavioral deficits reminiscent of behaviors observed in psychotic patients. The adult PRS brain, like that of postmortem chronic SZ patients, is characterized by a significant increase in DNA methyltransferase 1, Tet methylcytosine dioxygenase 1 (TET1), 5-methylcytosine, and 5-hydroxymethylcytosine at SZ candidate gene promoters and a reduction in the expression of glutamatergic and GABAergic genes. In PRS mice, measurements of epigenetic biomarkers for SZ can be assessed at different stages of development with the goal of further elucidating the pathophysiology of this disease and predicting treatment responses at specific stages of the illness, with particular attention to early detection and possibly early intervention.
    Progress in molecular biology and translational science 11/2014; 128:89-101. DOI:10.1016/B978-0-12-800977-2.00004-8 · 3.49 Impact Factor

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    Alessandro Guidotti · Dennis R Grayson ·
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    ABSTRACT: Schizophrenia (SZ) and bipolar disorder (BPD) patients show a downregulation of GAD67, reelin (RELN), brain-derived neurotrophic factor (BDNF), and other genes expressed in telencephalic GABAergic and glutamatergic neurons. This downregulation is associated with the enrichment of 5-methylcytosine and 5-hydroxymethylcytosine proximally at gene regulatory domains at the respective genes. A pharmacological strategy to reduce promoter hypermethylation and to induce a more permissive chromatin conformation is to administer drugs, such as the histone deacetylase (HDAC) inhibitor valproate (VPA), that facilitate chromatin remodeling. Studies in mouse models of SZ indicate that clozapine induces DNA demethylation at relevant promoters, and that this action is potentiated by VPA. By activating DNA demethylation, clozapine or its derivatives with VPA or other more potent and selective HDAC inhibitors may be a promising treatment strategy to correct the gene expression deficits detected in postmortem brain of SZ and BPD patients.
    Dialogues in clinical neuroscience 09/2014; 16(3):419-29.
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    Adrian Zhubi · Edwin H Cook · Alessandro Guidotti · Dennis R Grayson ·
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    ABSTRACT: Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by impaired social interactions, language deficits, as well as restrictive or repetitive behaviors. ASD is clinically heterogeneous with a complex etiopathogenesis which may be conceptualized as a dynamic interplay between heterogeneous environmental cues and predisposing genetic factors involving complex epigenetic mechanisms. Inherited and de novo copy number variants provide novel information regarding genes contributing to ASD. Epigenetic marks are stable, yet potentially reversible, chromatin modifications that alter gene expression profiles by locally changing the degree of nucleosomal compaction, thereby opening or closing promoter access to the transcriptional machinery. Here, we review progress on studies designed to provide a better understanding of how epigenetic mechanisms impact transcriptional programs operative in the brain that contribute to ASD.
    International Review of Neurobiology 08/2014; 115:203-44. DOI:10.1016/B978-0-12-801311-3.00006-8 · 1.92 Impact Factor
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    ABSTRACT: Background Prenatal stress is considered a risk factor for several neurodevelopmental disorders including schizophrenia (SZ). An animal model involving restraint stress of pregnant mice suggests that prenatal stress (PRS) induces epigenetic changes in specific GABAergic and glutamatergic genes likely to be implicated in SZ including the gene for brain derived neurotrophic factor (BDNF). Methods Studying adult offspring of pregnant mice subjected to PRS, we explored the long-term effects of PRS on behavior and on the expression of key chromatin remodeling factors including DNA methyltransferase 1 (DNMT1), ten-eleven translocation hydroxylases (TETs), methyl CpG binding protein 2 (MeCP2), histone deacetylases (HDACs), histone methyltransferases (MLL1, SETD1, G9a and EZH1) and demethylase (LSD1) in the frontal cortex (FC) and hippocampus (HP). We also measured the expression of BDNF. Results Adult PRS offspring demonstrate behavioral abnormalities suggestive of SZ and molecular changes similar to SZ postmortem brain: a significant increase in DNMT1 and TET1 in the FC and HP but not in cerebellum, no changes in HDACs, histone methytransferases/demethylases or MeCP2, and a significant decrease in BDNF mRNA variants. The decrease of the corresponding BDNF transcript level was accompanied by an enrichment of 5-methylcytosine and 5-hydroxymethylcytosine at Bdnf gene regulatory regions. In addition, the expression of BDNF transcripts (IV and IX) positively correlated with social approach in both PRS and non-stressed mice. Conclusions Since patients with psychosis and PRS mice show similar epigenetic signature, PRS offspring may be a suitable model for understanding the behavioral and molecular epigenetic changes observed in SZ patients.
    Biological Psychiatry 08/2014; 77(6). DOI:10.1016/j.biopsych.2014.08.012 · 10.26 Impact Factor
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    Roberto Carlos Agis-Balboa · Alessandro Guidotti · Graziano Pinna ·
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    ABSTRACT: Rationale The implications of the neurosteroid 3α-hydroxy-5α-pregnan-20-one [allopregnanolone (Allo)] in neuropsychiatric disorders have been highlighted in several recent clinical investigations. For instance, Allo levels are decreased in the cerebrospinal fluid (CSF) of patients with posttraumatic stress disorder (PTSD) and major unipolar depression. Neurosteroidogenic antidepressants [i.e., selective brain steroidogenic stimulants (SBSSs)], including fluoxetine and analogs, correct this decrease in a manner that correlates with improved depressive symptoms. Allo positively and allosterically modulatesGABAaction at postsynaptic and extrasynaptic GABAA receptors. It is synthesized in both the human and rodent brain cortices by principal glutamatergic pyramidal neurons from progesterone by the sequential action of 5α-reductase type I (5α-RI), which is the rate-limiting step enzyme in Allo biosynthesis, and 3α-hydroxysteroid dehydrogenase (3α-HSD), which converts 5α-dehydroprogesterone into Allo.
    Psychopharmacology 04/2014; 231(17). DOI:10.1007/s00213-014-3567-5 · 3.88 Impact Factor
  • A Guidotti · J Auta · Jm Davis · E Dong · Dp Gavin · Dr Grayson · Rp Sharma · Rc Smith · P Tueting · A Zhubi ·
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    ABSTRACT: Abstract Schizophrenia (SZ) is a heritable, non-mendelian, neurodevelopmental disorder in which epigenetic dysregulation of the brain genome plays a fundamental role in mediating the clinical manifestations and course of the disease. We recently reported that two enzymes that belong to the dynamic DNA-methylation/demethylation network -DNMT (DNA-methyltransferase) and TET (5-hydroxycytosine translocator)- are abnormally increased in cortico-limbic structures of SZ post-mortem brain suggesting a causal relationship between clinical manifestations of SZ and changes in DNA methylation and in the expression of SZ candidate genes (e.g., brain derived neurotrophic factor [BDNF], glucocorticoid receptor [GCR], glutamic acid decarboxylase67 [GAD67], reelin). Because the clinical manifestations of SZ typically begin with a prodrome followed by a first episode in adolescence with subsequent deterioration, it is obvious that the natural history of this disease cannot be studied only in post-mortem brain. Hence, the focus is currently shifting towards the feasibility of studying epigenetic molecular signatures of SZ in blood cells. Initial studies show a significant enrichment of epigenetic changes in lymphocytes in gene networks directly relevant to psychiatric disorders. Furthermore, the expression of DNA-methylating/demethylating enzymes and SZ candidate genes such as BDNF and GCR are altered in the same direction in both brain and blood lymphocytes. The coincidence of these changes in lymphocytes and brain supports the hypothesis that common environmental or genetic risk factors are operative in altering the epigenetic components involved in orchestrating transcription of specific genes in brain and peripheral tissues. The identification of DNA-methylation signatures for SZ in peripheral blood cells of subjects with genetic and clinical high risk would clearly have potential for the diagnosis of SZ early in its course and would be invaluable for initiating early intervention and individualized treatment plans.
    Journal of neurogenetics 04/2014; 28(1-2). DOI:10.3109/01677063.2014.892485 · 1.27 Impact Factor
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    A Zhubi · Y Chen · E Dong · E H Cook · A Guidotti · D R Grayson ·
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    ABSTRACT: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by symptoms related to altered social interactions/communication and restricted and repetitive behaviors. In addition to genetic risk, epigenetic mechanisms (which include DNA methylation/demethylation) are thought to be important in the etiopathogenesis of ASD. We studied epigenetic mechanisms underlying the transcriptional regulation of candidate genes in cerebella of ASD patients, including the binding of MeCP2 (methyl CpG binding protein-2) to the glutamic acid decarboxylase 67 (GAD1), glutamic acid decarboxylase 65 (GAD2), and Reelin (RELN) promoters and gene bodies. Moreover, we performed methyl DNA immunoprecipitation (MeDIP) and hydroxymethyl DNA immunoprecipitation (hMeDIP) to measure total 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in the same regions of these genes. The enrichment of 5-hmC and decrease in 5-mC at the GAD1 or RELN promoters detected by 5-hmC and 5-mC antibodies was confirmed by Tet-assisted bisulfite (TAB) pyrosequencing. The results showed a marked and significant increase in MeCP2 binding to the promoter regions of GAD1 and RELN, but not to the corresponding gene body regions in cerebellar cortex of ASD patients. Moreover, we detected a significant increase in TET1 expression and an enrichment in the level of 5-hmC, but not 5-mC, at the promoters of GAD1 and RELN in ASD when compared with CON. Moreover, there was increased TET1 binding to these promoter regions. These data are consistent with the hypothesis that an increase of 5-hmC (relative to 5-mC) at specific gene domains enhances the binding of MeCP2 to 5-hmC and reduces expression of the corresponding target genes in ASD cerebella.
    Translational Psychiatry 01/2014; 4(1):e349. DOI:10.1038/tp.2013.123 · 5.62 Impact Factor
  • J Auta · R C Smith · E Dong · P Tueting · H Sershen · S Boules · A Lajtha · J Davis · A Guidotti ·
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    ABSTRACT: The epigenetic dysregulation of the brain genome associated with the clinical manifestations of schizophrenia (SZ) includes altered DNA promoter methylation of several candidate genes. We and others have reported that two enzymes that belong to the DNA-methylation/demethylation network pathways-DNMT1 (DNA-methyltransferase) and ten-eleven translocator-1(TET1) methylcytosine deoxygenase are abnormally increased in corticolimbic structures of SZ postmortem brain. The objective of this study was to investigate whether the expression of these components of the DNA-methylation-demethylation pathways known to be altered in the brain of SZ patients are also altered in peripheral blood lymphocytes (PBL). The data show that increases in DNMT1 and TET1 and in glucocorticoid receptor (GCortR) and brain derived neurotrophic factor (BDNF) mRNAs in PBL of SZ patients are comparable to those reported in the brain of SZ patients. The finding that the expressions of DNMT1 and TET1 are increased and SZ candidate genes such as BDNF and GCortR are altered in the same direction in both the brain and PBL together with recent studies showing highly correlated patterns of DNA methylation across the brain and blood, support the hypothesis that a common epigenetic dysregulation may be operative in the brain and peripheral tissues of SZ patients.
    Schizophrenia Research 08/2013; 150(1). DOI:10.1016/j.schres.2013.07.030 · 3.92 Impact Factor
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    Kayla A Chase · David P Gavin · Alessandro Guidotti · Rajiv P Sharma ·
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    ABSTRACT: Epigenetic changes are stable and long-lasting chromatin modifications that regulate genomewide and local gene activity. The addition of two methyl groups to the 9th lysine of histone 3 (H3K9me2) by histone methyltransferases (HMT) leads to a restrictive chromatin state, and thus reduced levels of gene transcription. Given the numerous reports of transcriptional down-regulation of candidate genes in schizophrenia, we tested the hypothesis that this illness can be characterized by a restrictive epigenome. We obtained parietal cortical samples from the Stanley Foundation Neuropathology Consortium and lymphocyte samples from the University of Illinois at Chicago (UIC). In both tissues we measured mRNA expression of HMTs GLP, SETDB1 and G9a via real-time RT-PCR and H3K9me2 levels via western blot. Clinical rating scales were obtained from the UIC cohort. A diagnosis of schizophrenia is a significant predictor for increased GLP, SETDB1 mRNA expression and H3K9me2 levels in both postmortem brain and lymphocyte samples. G9a mRNA is significantly increased in the UIC lymphocyte samples as well. Increased HMT mRNA expression is associated with worsening of specific symptoms, longer durations of illness and a family history of schizophrenia. These data support the hypothesis of a restrictive epigenome in schizophrenia, and may associate with symptoms that are notoriously treatment resistant. The histone methyltransferases measured here are potential future therapeutic targets for small molecule pharmacology, and better patient prognosis.
    Schizophrenia Research 06/2013; 149(1-3). DOI:10.1016/j.schres.2013.06.021 · 3.92 Impact Factor
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    ABSTRACT: Background: Recent studies suggest that protracted and excessive alcohol use induces an epigenetic dysregulation in human and rodent brains. We recently reported that DNA methylation dynamics are altered in brains of psychotic (PS) patients, including schizophrenia and bipolar disorder patients. Because PS patients are often comorbid with chronic alcohol abuse, we examined whether the altered expression of multiple members of the DNA methylation/demethylation network observed in postmortem brains of PS patients was modified in PS patients with a history of chronic alcohol abuse. Methods: DNA-methyltransferase-1 (DNMT1) mRNA-positive neurons were counted in situ in prefrontal cortex samples obtained from the Harvard Brain Tissue Resource Center, Belmont, MA. 10-11-translocation (TETs 1, 2, 3), apolipoprotein B editing complex enzyme (APOBEC-3C), growth and DNA-damage-inducible protein 45β (GADD45β), and methyl-binding domain protein-4 (MBD4) mRNAs were measured by quantitative real-time polymerase chain reaction in inferior parietal cortical lobule samples obtained from the Stanley Foundation Neuropathology Consortium, Bethesda, MD. Results: We observed an increase in DNMT1 mRNA-positive neurons in PS patients compared with non-PS subjects. In addition, there was a pronounced decrease in APOBEC-3C and a pronounced increase in GADD45β and TET1 mRNAs in PS patients with no history of alcohol abuse. In PS patients with a history of chronic alcohol abuse, the numbers of DNMT1-positive neurons were not increased significantly. Furthermore, the decrease in APOBEC-3C mRNA was less pronounced, while the increase in TET1 mRNA had a tendency to be potentiated in those PS patients that were chronic alcohol abusers. GADD45β and MBD4 mRNAs were not influenced by alcohol abuse. The effect of chronic alcohol abuse on DNA methylation/demethylation network enzymes cannot be attributed to confounding demographic variables or to the type and dose of medication used. Conclusions: Based on these results, we hypothesize that PS patients may abuse alcohol as a potential attempt at self-medication to normalize altered DNA methylation/demethylation network pathways. However, before accepting this conclusion, we need to study alterations in the DNA methylation/demethylation pathways and the DNA methylation dynamics in a substantial number of alcoholic PS and non-PS patients. Additional investigation may also be necessary to determine whether the altered DNA methylation dynamics are direct or the consequence of an indirect interaction of alcohol with the neuropathogenetic mechanisms underlying psychosis.
    Alcoholism Clinical and Experimental Research 09/2012; 37(3). DOI:10.1111/j.1530-0277.2012.01947.x · 3.21 Impact Factor
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    Dennis R Grayson · Alessandro Guidotti ·
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    ABSTRACT: Major psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BP) with psychosis (BP+) express a complex symptomatology characterized by positive symptoms, negative symptoms, and cognitive impairment. Postmortem studies of human SZ and BP+ brains show considerable alterations in the transcriptome of a variety of cortical structures, including multiple mRNAs that are downregulated in both inhibitory GABAergic and excitatory pyramidal neurons compared with non-psychiatric subjects (NPS). Several reports show increased expression of DNA methyltransferases in telencephalic GABAergic neurons. Accumulating evidence suggests a critical role for altered DNA methylation processes in the pathogenesis of SZ and related psychiatric disorders. The establishment and maintenance of CpG site methylation is essential during central nervous system differentiation and this methylation has been implicated in synaptic plasticity, learning, and memory. Atypical hypermethylation of candidate gene promoters expressed in GABAergic neurons is associated with transcriptional downregulation of the corresponding mRNAs, including glutamic acid decarboxylase 67 (GAD67) and reelin (RELN). Recent reports indicate that the methylation status of promoter proximal CpG dinucleotides is in a dynamic balance between DNA methylation and DNA hydroxymethylation. Hydroxymethylation and subsequent DNA demethylation is more complex and involves additional proteins downstream of 5-hydroxymethylcytosine, including members of the base excision repair (BER) pathway. Recent advances in our understanding of altered CpG methylation, hydroxymethylation, and active DNA demethylation provide a framework for the identification of new targets, which may be exploited for the pharmacological intervention of the psychosis associated with SZ and possibly BP+.Neuropsychopharmacology Reviews advance online publication, 5 September 2012; doi:10.1038/npp.2012.125.
    Neuropsychopharmacology: official publication of the American College of Neuropsychopharmacology 09/2012; 38(1). DOI:10.1038/npp.2012.125 · 7.05 Impact Factor
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    Bashkim Kadriu · Alessandro Guidotti · Ying Chen · Dennis R Grayson ·
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    ABSTRACT: DNA methylation is an epigenetic regulatory mechanism commonly associated with transcriptional silencing. DNA methyltransferases (DNMTs) are a family of related proteins that both catalyze the de novo formation of 5-methylcytosine and maintain these methylation marks in cell-specific patterns in virtually all mitotic cells of the body. In the adult brain, methylation occurs in progenitor cells of the neurogenic zones and in postmitotic neurons. Of the DNMTs, DNMT1 and DNMT3a are most highly expressed in postmitotic neurons. While it has been commonly thought all postmitotic neurons and glia express DNMTs at comparable levels, the coexpression of selected DNMTs with markers of distinct neurotransmitter phenotypes has not been previously examined in detail in the mouse. To this end, we analyzed the expression of DNMT1 and DNMT3a along with GAD67 in the brains of the glutamic acid decarboxylase67-enhanced green fluorescent protein (GAD67-GFP) knockin mice. After first confirming that GFP-immunopositive neurons were also GAD67-positive, we showed that in the motor cortex, piriform cortex, striatum, CA1 region of the hippocampus, dentate gyrus, and basolateral amygdala (BLA), GFP immunofluorescence coincided with the signal corresponding to DNMT1 and DNMT3a. A detailed examination of cortical neurons, showed that ≈30% of NeuN-immunopositive neurons were also DNMT1-positive. These data do not exclude the expression of DNMT1 or DNMT3a in glutamatergic neurons and glia. However, they suggest that their expression is low compared with the levels present in GABAergic neurons.
    The Journal of Comparative Neurology 06/2012; 520(9):1951-64. DOI:10.1002/cne.23020 · 3.23 Impact Factor
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    ABSTRACT: Human studies suggest that a variety of prenatal stressors are related to high risk for cognitive and behavioral abnormalities associated with psychiatric illness (Markham and Koenig, 2011). Recently, a downregulation in the expression of GABAergic genes (i.e., glutamic acid decarboxylase 67 and reelin) associated with DNA methyltransferase (DNMT) overexpression in GABAergic neurons has been regarded as a characteristic phenotypic component of the neuropathology of psychotic disorders (Guidotti et al., 2011). Here, we characterized mice exposed to prenatal restraint stress (PRS) in order to study neurochemical and behavioral abnormalities related to development of schizophrenia in the adult. Offspring born from non-stressed mothers (control mice) showed high levels of DNMT1 and 3a mRNA expression in the frontal cortex at birth, but these levels progressively decreased at post-natal days (PND) 7, 14, and 60. Offspring born from stressed mothers (PRS mice) showed increased levels of DNMTs compared to controls at all time-points studied including at birth and at PND 60. Using GAD67-GFP transgenic mice, we established that, in both control and PRS mice, high levels of DNMT1 and 3a were preferentially expressed in GABAergic neurons of frontal cortex and hippocampus. Importantly, the overexpression of DNMT in GABAergic neurons was associated with a decrease in reelin and GAD67 expression in PRS mice in early and adult life. PRS mice also showed an increased binding of DNMT1 and MeCP2, and an increase in 5-methylcytosine and 5-hydroxymethylcytosine in specific CpG-rich regions of the reelin and GAD67 promoters. Thus, the epigenetic changes in PRS mice are similar to changes observed in the post-mortem brains of psychiatric patients. Behaviorally, adult PRS mice showed hyperactivity and deficits in social interaction, prepulse inhibition, and fear conditioning that were corrected by administration of valproic acid (a histone deacetylase inhibitor) or clozapine (an atypical antipsychotic with DNA-demethylation activity). Taken together, these data show that prenatal stress in mice induces abnormalities in the DNA methylation network and in behaviors indicative of a schizophrenia-like phenotype. Thus, PRS mice may be a valid model for the investigation of new drugs for schizophrenia treatment targeting DNA methylation. This article is part of a Special Issue entitled 'Neurodevelopment Disorder'.
    Neuropharmacology 04/2012; 68. DOI:10.1016/j.neuropharm.2012.04.013 · 5.11 Impact Factor
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    ABSTRACT: Prenatal exposure to restraint stress causes long-lasting changes in neuroplasticity that likely reflect pathological modifications triggered by early-life stress. We found that the offspring of dams exposed to repeated episodes of restraint stress during pregnancy (here named 'prenatal restraint stress mice' or 'PRS mice') developed a schizophrenia-like phenotype, characterized by a decreased expression of brain-derived neurotrophic factor and glutamic acid decarboxylase 67, an increased expression of type-1 DNA methyl transferase (DNMT1) in the frontal cortex, and a deficit in social interaction, locomotor activity, and prepulse inhibition. PRS mice also showed a marked decrease in metabotropic glutamate 2 (mGlu2) and mGlu3 receptor mRNA and protein levels in the frontal cortex, which was manifested at birth and persisted in adult life. This decrease was associated with an increased binding of DNMT1 to CpG-rich regions of mGlu2 and mGlu3 receptor promoters and an increased binding of MeCP2 to the mGlu2 receptor promoter. Systemic treatment with the selective mGlu2/3 receptor agonist LY379268 (0.5 mg/kg, i.p., twice daily for 5 days), corrected all the biochemical and behavioral abnormalities shown in PRS mice. Our data show for the first time that PRS induces a schizophrenia-like phenotype in mice, and suggest that epigenetic changes in mGlu2 and mGlu3 receptors lie at the core of the pathological programming induced by early-life stress.
    Neuropsychopharmacology: official publication of the American College of Neuropsychopharmacology 11/2011; 37(4):929-38. DOI:10.1038/npp.2011.274 · 7.05 Impact Factor

Publication Stats

24k Citations
2,454.49 Total Impact Points


  • 1996-2015
    • University of Illinois at Chicago
      • Department of Psychiatry (Chicago)
      Chicago, Illinois, United States
  • 2010
    • University of Chicago
      Chicago, Illinois, United States
  • 1995-2010
    • Nathan Kline Institute
      Orangeburg, New York, United States
    • Louisiana State University Health Sciences Center New Orleans
      • Department of Pharmacology and Experimental Therapeutics
      New Orleans, Louisiana, United States
  • 2008
    • Pennsylvania Psychiatric Institute
      Гаррисберг, Arkansas, United States
  • 1987-2006
    • Georgetown University
      • • Fidia-Georgetown Institute for the Neurosciences
      • • Department of Medicine
      Washington, Washington, D.C., United States
  • 1998
    • University of Groningen
      • Department of Medicinal Chemistry
      Groningen, Groningen, Netherlands
  • 1997
    • University of Santiago de Compostela
      • Department of Morphological Sciences
      Santiago, Galicia, Spain
  • 1992
    • The Neurosciences Institute
      La Jolla, California, United States
    • University of Padova
      Padua, Veneto, Italy
  • 1990
    • Universität Heidelberg
      • Center for Molecular Biology (ZMBH)
      Heidelburg, Baden-Württemberg, Germany
  • 1989
    • National Institute on Alcohol Abuse and Alcoholism
      Роквилл, Maryland, United States
  • 1973-1987
    • National Institute of Mental Health (NIMH)
      Maryland, United States
  • 1985
    • Max Planck Institute for Biophysical Chemistry
      Göttingen, Lower Saxony, Germany
  • 1977-1983
    • College of Saint Elizabeth
      Washington, Washington, D.C., United States
  • 1975-1983
    • District of Columbia Department of Mental Health
      Washington, Washington, D.C., United States
    • National Heart, Lung, and Blood Institute
      Maryland, United States
  • 1982
    • Rutgers New Jersey Medical School
      Newark, New Jersey, United States
  • 1974
    • St. Elizabeth Hospital
      Louisiana, United States
  • 1972
    • Università degli studi di Cagliari
      Cagliari, Sardinia, Italy
  • 1964-1971
    • University of Florence
      • Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino
      Florens, Tuscany, Italy