1 4390 139 MODELING THE MOLECULAR EPIGENETIC PROFILE OF PSYCHOSIS IN PRENATALLY STRESSED MICE. 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. 2014 2 1538 45 DNA METHYLATION IN ANIMAL MODELS OF PSYCHOSIS. SCHIZOPHRENIA (SZ) IS A DEBILITATING DISEASE THAT IMPACTS 1% OF THE POPULATION WORLDWIDE. ASSOCIATION STUDIES HAVE SHOWN THAT INHERITED GENETIC MUTATIONS ACCOUNT FOR A PORTION OF DISEASE RISK. HOWEVER, ENVIRONMENTAL FACTORS PLAY AN IMPORTANT ROLE IN THE PATHOPHYSIOLOGY OF THE DISEASE BY ALTERING CELLULAR EPIGENETIC MARKS AT THE LEVEL OF CHROMATIN. POSTMORTEM BRAIN STUDIES OF SZ SUBJECTS SUGGEST THAT THE DYNAMIC EQUILIBRIUM BETWEEN DNA METHYLATION AND DEMETHYLATION NETWORK COMPONENTS IS DISRUPTED AT THE LEVEL OF INDIVIDUAL SZ TARGET GENES. HEREIN, WE REVIEW THE ROLE OF DNA METHYLATION AND DEMETHYLATION IN THE CONTEXT OF WHAT IS CURRENTLY KNOWN REGARDING SZ. FURTHERMORE, WE DESCRIBE THE DEFICITS THAT ACCOMPANY TWO MOUSE MODELS OF SZ. THE CHRONIC METHIONINE MOUSE MODEL OF SZ IS PREDICATED ON THE ADMINISTRATION OF METHIONINE TO SZ PATIENTS AND CONTROLS IN THE CONTEXT OF CLINICAL STUDIES THAT WERE CARRIED OUT DURING THE 1960S AND 1970S. THE PRENATAL RESTRAINT STRESS MODEL OF SZ IS BASED ON A PROLONGED STRESS PARADIGM ADMINISTERED TO PREGNANT DAMS DURING GESTATION DAYS 7-21. THE ADULT OFFSPRING OF THESE DAMS SHOW VARIOUS BEHAVIORAL AND BIOCHEMICAL DEFICITS IN ADULTHOOD. BOTH MODELS ARE EPIGENETIC IN ORIGIN AND MIMIC THE POSITIVE AND NEGATIVE SYMPTOMS, AS WELL AS THE COGNITIVE ENDOPHENOTYPES COMMONLY OBSERVED IN SZ PATIENTS. WE ALSO DISCUSS THE UTILITY OF TYPICAL AND ATYPICAL ANTIPSYCHOTIC DRUGS IN ALLEVIATING THESE SYMPTOMS IN EACH MODEL. 2018 3 252 29 ADVANCEMENTS IN THE UNDERLYING PATHOGENESIS OF SCHIZOPHRENIA: IMPLICATIONS OF DNA METHYLATION IN GLIAL CELLS. SCHIZOPHRENIA (SZ) IS A CHRONIC AND SEVERE MENTAL ILLNESS FOR WHICH CURRENTLY THERE IS NO CURE. AT PRESENT, THE EXACT MOLECULAR MECHANISM INVOLVED IN THE UNDERLYING PATHOGENESIS OF SZ IS UNKNOWN. THE DISEASE IS THOUGHT TO BE CAUSED BY A COMBINATION OF GENETIC, BIOLOGICAL, PSYCHOLOGICAL, AND ENVIRONMENTAL FACTORS. RECENT STUDIES HAVE SHOWN THAT EPIGENETIC REGULATION IS INVOLVED IN SZ PATHOLOGY. SPECIFICALLY, DNA METHYLATION, ONE OF THE EARLIEST FOUND EPIGENETIC MODIFICATIONS, HAS BEEN EXTENSIVELY LINKED TO MODULATION OF NEURONAL FUNCTION, LEADING TO PSYCHIATRIC DISORDERS SUCH AS SZ. HOWEVER, INCREASING EVIDENCE INDICATES THAT GLIAL CELLS, ESPECIALLY DYSFUNCTIONAL OLIGODENDROCYTES UNDERGO DNA METHYLATION CHANGES THAT CONTRIBUTE TO THE PATHOGENESIS OF SZ. THIS REVIEW PRIMARILY FOCUSES ON DNA METHYLATION INVOLVED IN GLIAL DYSFUNCTIONS IN SZ. CLARIFYING THIS MECHANISM MAY LEAD TO THE DEVELOPMENT OF NEW THERAPEUTIC INTERVENTIONAL STRATEGIES FOR THE TREATMENT OF SZ AND OTHER ILLNESSES BY CORRECTING ABNORMAL METHYLATION IN GLIAL CELLS. 2015 4 579 62 BEHAVIORAL AND MOLECULAR NEUROEPIGENETIC ALTERATIONS IN PRENATALLY STRESSED MICE: RELEVANCE FOR THE STUDY OF CHROMATIN REMODELING PROPERTIES OF ANTIPSYCHOTIC DRUGS. WE HAVE RECENTLY REPORTED THAT MICE BORN FROM DAMS STRESSED DURING PREGNANCY (PRS MICE), IN ADULTHOOD, HAVE BEHAVIORAL DEFICITS REMINISCENT OF BEHAVIORS OBSERVED IN SCHIZOPHRENIA (SZ) AND BIPOLAR (BP) DISORDER PATIENTS. FURTHERMORE, WE HAVE SHOWN THAT THE FRONTAL CORTEX (FC) AND HIPPOCAMPUS OF ADULT PRS MICE, LIKE THAT OF POSTMORTEM CHRONIC SZ PATIENTS, ARE CHARACTERIZED BY INCREASES IN DNA-METHYLTRANSFERASE 1 (DNMT1), TEN-ELEVEN METHYLCYTOSINE DIOXYGENASE 1 (TET1) AND EXHIBIT AN ENRICHMENT OF 5-METHYLCYTOSINE (5MC) AND 5-HYDROXYMETHYLCYTOSINE (5HMC) AT NEOCORTICAL GABAERGIC AND GLUTAMATERGIC GENE PROMOTERS. HERE, WE SHOW THAT THE BEHAVIORAL DEFICITS AND THE INCREASED 5MC AND 5HMC AT GLUTAMIC ACID DECARBOXYLASE 67 (GAD1), REELIN (RELN) AND BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) PROMOTERS AND THE REDUCED EXPRESSION OF THE MESSENGER RNAS (MRNAS) AND PROTEINS CORRESPONDING TO THESE GENES IN FC OF ADULT PRS MICE IS REVERSED BY TREATMENT WITH CLOZAPINE (5 MG KG(-1) TWICE A DAY FOR 5 DAYS) BUT NOT BY HALOPERIDOL (1 MG KG(-1) TWICE A DAY FOR 5 DAYS). INTERESTINGLY, CLOZAPINE HAD NO EFFECT ON EITHER THE BEHAVIOR, PROMOTER METHYLATION OR THE EXPRESSION OF THESE MRNAS AND PROTEINS WHEN ADMINISTERED TO OFFSPRING OF NONSTRESSED PREGNANT MICE. CLOZAPINE, BUT NOT HALOPERIDOL, REDUCED THE ELEVATED LEVELS OF DNMT1 AND TET1, AS WELL AS THE ELEVATED LEVELS OF DNMT1 BINDING TO GAD1, RELN AND BDNF PROMOTERS IN PRS MICE SUGGESTING THAT CLOZAPINE, UNLIKE HALOPERIDOL, MAY LIMIT DNA METHYLATION BY INTERFERING WITH DNA METHYLATION DYNAMICS. WE CONCLUDE THAT THE PRS MOUSE MODEL MAY BE USEFUL PRECLINICALLY IN SCREENING FOR THE POTENTIAL EFFICACY OF ANTIPSYCHOTIC DRUGS ACTING ON ALTERED EPIGENETIC MECHANISMS. FURTHERMORE, PRS MICE MAY BE INVALUABLE FOR UNDERSTANDING THE ETIOPATHOGENESIS OF SZ AND BP DISORDER AND FOR PREDICTING TREATMENT RESPONSES AT EARLY STAGES OF THE ILLNESS ALLOWING FOR EARLY DETECTION AND REMEDIAL INTERVENTION. 2016 5 486 29 ASENAPINE TRANSDERMAL PATCH FOR THE MANAGEMENT OF SCHIZOPHRENIA. PURPOSE OF REVIEW: THIS IS A COMPREHENSIVE REVIEW OF THE LITERATURE REGARDING THE USE OF ASENAPINE FOR THE TREATMENT OF SCHIZOPHRENIA (SZ) IN ADULTS. IT COVERS AN INTRODUCTION, EPIDEMIOLOGY, RISK FACTORS, PATHOPHYSIOLOGY, AND CURRENT TREATMENT MODALITIES REGARDING SZ, PROVIDES A BACKGROUND ON THE MECHANISM OF ACTION OF ASENAPINE, AND THEN REVIEWS THE EXISTING EVIDENCE FOR USE OF ASENAPINE IN BOTH ITS SUBLINGUAL AND TRANSDERMAL FORMULATION IN THE TREATMENT OF SZ. RECENT FINDINGS: SZ IS A COMPLEX AND MULTIFACTORIAL MENTAL DISORDER WHICH IS THOUGHT TO COMBINE SEVERAL GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS CAUSING ABNORMALITIES IN THE DOPAMINERGIC SYSTEM. SYMPTOMS ARE CATEGORIZED IN DELUSIONS, HALLUCINATIONS, DISORGANIZATION, AND NEGATIVE PRESENTATIONS LIKE AFFECTIVE FLATTENING AND APATHY. CURRENT TREATMENT FOCUSES ON ANTIPSYCHOTIC MEDICATIONS BY MEANS OF ORAL ADMINISTRATION OR LONG-ACTING INJECTION. ASENAPINE IS A SECOND-GENERATION ANTIPSYCHOTIC WITH 5HT-2A ANTAGONIST AND 5HT-1A/1B PARTIAL AGONIST PROPERTIES, WHICH PROVIDES A FAVORABLE PROFILE IN TARGETING SCHIZOPHRENIC SYMPTOMS, WHILE REDUCING MOTOR SIDE EFFECTS AND IMPROVING MOOD AND COGNITION. ASENAPINE IN ITS SUBLINGUAL FORMULATION WAS FDA APPROVED FOR TREATMENT OF SZ AND BIPOLAR I DISORDER IN ADULTS IN AUGUST OF 2009 AND HAS BEEN PROVEN TO BE BOTH EFFECTIVE AND SAFE. TRANSDERMAL PATCH OF ASENAPINE (SECUADO) WAS FDA APPROVED IN OCTOBER OF 2019, THE FIRST AND ONLY FDA APPROVED PATCH FOR SZ IN ADULTS, WHICH OFFERS ANOTHER STRATEGY FOR TREATMENT TO IMPROVE COMPLIANCE AND EASE OF ADMINISTRATION. SUMMARY: SZ IS A CHRONIC AND DEBILITATING DISEASE WHICH IS STILL NOT WELL UNDERSTOOD AND COMES AT GREAT COST WITH REGARDS TO THE QUALITY OF LIFE FOR PATIENTS. MEDICATION SIDE-EFFECTS AND COMPLIANCE ARE ENORMOUS ISSUES WHICH TAKE A TOLL ON HEALTH CARE SYSTEMS IN INDUSTRIALIZED NATIONS AND KEEP PATIENTS FROM ACHIEVING STABILITY WITH THEIR DISEASE. TRANSDERMAL ASENAPINE IS A NEW FIRST-IN-CLASS DOSAGE FORM AND PROVIDES A NOVEL MODALITY OF ADMINISTRATION. IT HAS BEEN SHOWN TO BE EFFECTIVE IN REDUCING POSITIVE, AS WELL AS NEGATIVE SYMPTOMS, WHILE STILL MAINTAINING A FAVORABLE SIDE-EFFECT PROFILE. 2020 6 3133 28 GLOBAL DNA HYPOMETHYLATION AND ITS CORRELATION TO THE BETAINE LEVEL IN PERIPHERAL BLOOD OF PATIENTS WITH SCHIZOPHRENIA. ACCUMULATING EVIDENCE SUGGESTS THAT ABERRANT EPIGENETIC REGULATION IS INVOLVED IN THE PATHOPHYSIOLOGY OF MAJOR PSYCHIATRIC DISORDERS SUCH AS SCHIZOPHRENIA (SZ) AND BIPOLAR DISORDER (BD). WE PREVIOUSLY SHOWED THAT THE PLASMA LEVEL OF BETAINE (N,N,N-TRIMETHYLGLYCINE), A METHYL-GROUP DONOR, WAS SIGNIFICANTLY DECREASED IN PATIENTS WITH FIRST EPISODE SCHIZOPHRENIA (FESZ). IN THIS STUDY, WE IDENTIFIED DECREASE OF GLOBAL DNA METHYLATION LEVEL IN FESZ (N = 24 PATIENTS VS N = 42 CONTROLS), AND FOUND THAT GLOBAL DNA METHYLATION LEVEL WAS INVERSELY CORRELATED WITH SCORES ON THE GLOBAL ASSESSMENT OF FUNCTIONING (GAF) SCALE, AND POSITIVELY CORRELATED WITH PLASMA BETAINE LEVEL. NOTABLY, CORRELATIONS BETWEEN LEVELS OF BETAINE AND ITS METABOLITES (N,N-DIMETHYLGLYCINE AND SARCOSINE, N-METHYLGLYCINE) WERE LOWER OR LOST IN FESZ PLASMA, BUT REMAINED HIGH IN CONTROLS. WE FURTHER EXAMINED GLOBAL DNA METHYLATION LEVELS IN PATIENTS WITH CHRONIC SZ (N = 388) AND BD (N = 414) AS WELL AS CONTROLS (N = 430), AND CONFIRMED SIGNIFICANT HYPOMETHYLATION AND DECREASED BETAINE LEVEL IN SZ. WE ALSO FOUND THAT PATIENTS WITH BD TYPE I, BUT NOT THOSE WITH BD TYPE II, SHOWED SIGNIFICANT GLOBAL HYPOMETHYLATION. THESE RESULTS SUGGEST THAT GLOBAL HYPOMETHYLATION ASSOCIATED WITH DECREASED BETAINE LEVEL IN BLOOD CELLS IS COMMON TO SZ AND BD, AND MAY REFLECT COMMON PATHOPHYSIOLOGY SUCH AS PSYCHOTIC SYMPTOMS. 2020 7 5267 30 PROMOTER ACTIVITY-BASED CASE-CONTROL ASSOCIATION STUDY ON SLC6A4 HIGHLIGHTING HYPERMETHYLATION AND ALTERED AMYGDALA VOLUME IN MALE PATIENTS WITH SCHIZOPHRENIA. ASSOCIATIONS BETWEEN ALTERED DNA METHYLATION OF THE SEROTONIN TRANSPORTER (5-HTT)-ENCODING GENE SLC6A4 AND EARLY LIFE ADVERSITY, MOOD AND ANXIETY DISORDERS, AND AMYGDALA REACTIVITY HAVE BEEN REPORTED. HOWEVER, FEW STUDIES HAVE EXAMINED EPIGENETIC ALTERATIONS OF SLC6A4 IN SCHIZOPHRENIA (SZ). WE EXAMINED CPG SITES OF SLC6A4, WHOSE DNA METHYLATION LEVELS HAVE BEEN REPORTED TO BE ALTERED IN BIPOLAR DISORDER, USING 3 INDEPENDENT COHORTS OF PATIENTS WITH SZ AND AGE-MATCHED CONTROLS. WE FOUND SIGNIFICANT HYPERMETHYLATION OF A CPG SITE IN SLC6A4 IN MALE PATIENTS WITH SZ IN ALL 3 COHORTS. WE SHOWED THAT CHRONIC ADMINISTRATION OF RISPERIDONE DID NOT AFFECT THE DNA METHYLATION STATUS AT THIS CPG SITE USING COMMON MARMOSETS, AND THAT IN VITRO DNA METHYLATION AT THIS CPG SITE DIMINISHED THE PROMOTER ACTIVITY OF SLC6A4. WE THEN GENOTYPED THE 5-HTT-LINKED POLYMORPHIC REGION (5-HTTLPR) AND INVESTIGATED THE RELATIONSHIP AMONG 5-HTTLPR, DNA METHYLATION, AND AMYGDALA VOLUME USING BRAIN IMAGING DATA. WE FOUND THAT PATIENTS HARBORING LOW-ACTIVITY 5-HTTLPR ALLELES SHOWED HYPERMETHYLATION AND THEY SHOWED A NEGATIVE CORRELATION BETWEEN DNA METHYLATION LEVELS AND LEFT AMYGDALA VOLUMES. THESE RESULTS SUGGEST THAT HYPERMETHYLATION OF THE CPG SITE IN SLC6A4 IS INVOLVED IN THE PATHOPHYSIOLOGY OF SZ, ESPECIALLY IN MALE PATIENTS HARBORING LOW-ACTIVITY 5-HTTLPR ALLELES. 2020 8 4370 35 MIRNAS AND THEIR ROLE IN THE CORRELATION BETWEEN SCHIZOPHRENIA AND CANCER (REVIEW). SCHIZOPHRENIA (SZ) AND CANCER (CA) HAVE A BROAD SPECTRUM OF CLINICAL PHENOTYPES AND A COMPLEX BIOLOGICAL BACKGROUND, IMPLICATING A LARGE NUMBER OF GENETIC AND EPIGENETIC FACTORS. SZ IS A CHRONIC NEURODEVELOPMENTAL DISORDER SIGNIFIED BY AN INCREASE IN THE EXPRESSION OF APOPTOTIC MOLECULAR SIGNALS, WHEREAS CA IS CONVERSELY CHARACTERIZED BY AN INCREASE IN APPROPRIATE MOLECULAR SIGNALING THAT STIMULATES UNCONTROLLED CELL PROLIFERATION. THE RATHER LOW RISK OF DEVELOPING CA IN PATIENTS SUFFERING FROM SZ IS A HYPOTHESIS THAT IS STILL UNDER DEBATE. RECENT EVIDENCE HAS INDICATED THAT MICRORNAS (MIRNAS OR MIRS), A LARGE GROUP OF SMALL NON?CODING OLIGONOUCLEOTIDES, MAY PLAY A SIGNIFICANT ROLE IN THE DEVELOPMENT OF CA AND MAJOR PSYCHIATRIC DISORDERS, SUCH AS SZ, BIPOLAR DISORDER, AUTISM SPECTRUM DISORDERS, SUICIDALITY AND DEPRESSION, THROUGH THEIR INTERFERENCE WITH THE EXPRESSION OF MULTIPLE GENES. FOR INSTANCE, THE POSSIBLE ROLE OF LET?7, MIR?98 AND MIR?183 AS BIOMARKERS FOR CA AND SZ WAS INVESTIGATED IN OUR PREVIOUS RESEARCH STUDIES. THEREFORE, FURTHER INVESTIGATIONS ON THE EXPRESSION PROFILES OF THESE REGULATORY, SMALL RNA MOLECULES AND THE MOLECULAR PATHWAYS THROUGH WHICH THEY EXERT THEIR CONTROL MAY PROVIDE A PLAUSIBLE EXPLANATION AS TO WHETHER THERE IS A CORRELATION BETWEEN PSYCHIATRIC DISORDERS AND LOW RISK OF DEVELOPING CA. 2016 9 1179 24 CONVERGENCE AND DIVERGENCE IN THE ETIOLOGY OF MYELIN IMPAIRMENT IN PSYCHIATRIC DISORDERS AND DRUG ADDICTION. IMPAIRMENT OF OLIGODENDROGLIA (OL)-DEPENDENT MYELINATION IN THE CENTRAL NERVOUS SYSTEM (CNS) IS A REMARKABLE PARALLEL RECENTLY IDENTIFIED IN MAJOR PSYCHIATRIC DISORDERS AND CHRONIC DRUG ABUSE. NEUROIMAGING AND NEUROPATHOLOGICAL STUDIES REVEALED MYELIN DEFECTS AND MICROARRAY-PROFILING ANALYSIS DEMONSTRATED ABERRANT EXPRESSION OF MYELIN-RELATED GENES IN SCHIZOPHRENIA (SZ), BIPOLAR DISORDER (BD), MAJOR DEPRESSIVE DISORDER (MDD) AND COCAINE ADDICTION. HOWEVER, THE ETIOLOGY UNDERLYING MYELIN IMPAIRMENT IN THESE CLINICALLY DISTINCT SUBJECTS REMAINS ELUSIVE. THIS ARTICLE REVIEWS MYELIN IMPAIRMENT IN LINE WITH DOPAMINERGIC DYSFUNCTION, A PRIME NEUROPATHOPHYSIOLOGICAL TRAIT SHARED IN PSYCHIATRIC DISORDERS AND DRUG ABUSE, AS WELL AS THE GENETIC AND EPIGENETIC ALTERATIONS ASSOCIATED WITH THESE DISEASES. THE CURRENT FINDINGS SUPPORT THE HYPOTHESIS THAT ABERRANT DOPAMINE (DA) ACTION ON OLS IS A COMMON PATHOLOGIC MECHANISM FOR MYELIN IMPAIRMENT IN THE AFOREMENTIONED MENTAL MORBIDITIES, WHEREAS INHERITED GENETIC VARIATIONS THAT SPECIFICALLY AFFECT OL DEVELOPMENT AND MYELINOGENESIS MAY FURTHER INCREASE MYELIN VULNERABILITY IN PSYCHIATRIC DISORDERS. IMPORTANTLY, OL DEFECT IS NOT ONLY A PATHOLOGICAL CONSEQUENCE BUT ALSO A CAUSATIVE FACTOR FOR DOPAMINERGIC DYSFUNCTION. HENCE, MYELIN IMPAIRMENT IS A KEY FACTOR IN THE PATHOGENIC LOOP OF PSYCHIATRIC DISEASES AND DRUG ADDICTION. 2008 10 1299 28 DECREASED REELIN EXPRESSION IN THE LEFT PREFRONTAL CORTEX (BA9) IN CHRONIC SCHIZOPHRENIA PATIENTS. BACKGROUND: REELIN IS UNDER EPIGENETIC CONTROL AND HAS BEEN REPORTED TO BE DECREASED IN CORTICAL REGIONS IN SCHIZOPHRENIA. METHODS: TO ESTABLISH IF EXPRESSION OF REELIN IS ALTERED IN SPECIFIC CORTICAL, HIPPOCAMPAL OR THALAMIC REGIONS OF SCHIZOPHRENIA PATIENTS, WE MEASURED GENE EXPRESSION OF REELIN IN A POSTMORTEM STUDY OF ELDERLY PATIENTS WITH SCHIZOPHRENIA AND NON-AFFECTED CONTROLS IN BOTH HEMISPHERES DIFFERENTIATING BETWEEN GRAY AND WHITE MATTER. WE COMPARED CEREBRAL POSTMORTEM SAMPLES (DORSOLATERAL PREFRONTAL CORTEX BA9 AND BA46, SUPERIOR TEMPORAL CORTEX BA22, ENTORHINAL CORTEX BA28, SENSORIC CORTEX BA1-3, HIPPOCAMPUS, CA4, MEDIODORSAL NUCLEUS OF THE THALAMUS) FROM 12 SCHIZOPHRENIA PATIENTS WITH 13 NORMAL SUBJECTS INVESTIGATING GENE EXPRESSION OF REELIN IN THE GRAY AND WHITE MATTER OF BOTH HEMISPHERES BY IN SITU-HYBRIDIZATION. RESULTS: THE LEFT PREFRONTAL AREA (BA9) OF SCHIZOPHRENIA PATIENTS REVEALED A DECREASED EXPRESSION OF REELIN-MRNA OF 29.1% IN THE WHITE (P = 0.022) AND 13.6% IN THE GRAY MATTER (P = 0.007) COMPARED TO THE CONTROL GROUP. NONE OF THE OTHER REGIONS EXAMINED SHOWED ANY STATISTICALLY SIGNIFICANT DIFFERENCES. CONCLUSION: SINCE REELIN IS RESPONSIBLE FOR MIGRATION AND SYNAPSE FORMATION, THE DECREASED GENE EXPRESSION OF REELIN IN THE LEFT PREFRONTAL AREA OF SCHIZOPHRENIA PATIENTS POINTS TO NEURODEVELOPMENTAL DEFICITS IN NEURONAL MIGRATION AND SYNAPTIC PLASTICITY. HOWEVER, OUR STUDY GROUP WAS SMALL, AND RESULTS SHOULD BE VERIFIED USING LARGER SAMPLES. 2012 11 4525 28 MULTIFACTORIAL CAUSES OF PARANOID SCHIZOPHRENIA WITH AUDITORY-VISUAL HALLUCINATIONS IN A 31-YEAR-OLD MALE WITH HISTORY OF TRAUMATIC BRAIN INJURY AND SUBSTANCE ABUSE. SCHIZOPHRENIA IS A CHRONIC PSYCHIATRIC DISORDER THAT CLASSICALLY PRESENTS WITH DISTORTIONS OF THOUGHT, BEHAVIOR, AND PERCEPTIONS THAT ARE OFTEN MISDIAGNOSED. ONE DIFFICULTY IN DIAGNOSING SCHIZOPHRENIA IS DUE TO ITS PHENOTYPICALLY HETEROGENEOUS CONDITION THAT CAN BE PRECIPITATED BY A COMBINATION OF GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS. THE PREVALENCE OF SCHIZOPHRENIA IS ROUGHLY 1%, BUT IT IS OFTEN MISDIAGNOSED. POSSIBLE DIFFERENTIAL DIAGNOSES INCLUDE DEPRESSION OR BIPOLAR DISORDER WITH PSYCHOSIS, PSYCHOSIS DUE TO A MEDICAL CONDITION, SCHIZOTYPAL AND SCHIZOID PERSONALITY DISORDERS, AND NEUROCOGNITIVE DISORDERS. IN THIS CASE REPORT, A 31-YEAR-OLD MALE PRESENTS WITH THOUGHTS OF SUICIDE FOLLOWING A RECENT EXACERBATION OF HIS HALLUCINATIONS. ON PRESENTATION, THE PATIENT PRESENTED WITH A HISTORICAL DIAGNOSIS OF "PARANOID SCHIZOPHRENIA" AS WELL AS A HISTORY OF TRAUMATIC BRAIN INJURY (TBI), POLY-SUBSTANCE USE DISORDER, AND A FAMILY HISTORY OF SCHIZOPHRENIA. THIS CASE SERVES TO HIGHLIGHT THE DIFFICULTIES OF MAKING AN ACCURATE DIAGNOSIS AND PROVIDING EVIDENCED-BASED TREATMENT. 2022 12 1810 29 EFFECTS OF ANTIPSYCHOTICS ON THE BDNF IN SCHIZOPHRENIA. BRAIN-DERIVED NEUROTROPIC FACTOR (BDNF) IS INVOLVED IN THE DEVELOPMENT OF THE BRAIN, AND LIKELY INFLUENCES THE NEUROPLASTICITY IN SCHIZOPHRENIA. BDNF IS ALSO BELIEVED TO INTERACT WITH OTHER NEUROTRANSMITTER SYSTEMS IMPLICATED IN SCHIZOPHRENIA, SUCH AS DOPAMINE, GLUTAMATE, SEROTONIN AND GABA. THEREFORE, BDNF IS A CANDIDATE GENE FOR SCHIZOPHRENIA. IN PAST DECADES, THE BLOOD (SERUM OR PLASMA) BDNF PROTEIN LEVELS AND BDNF GENE ALLELES AND GENOTYPES TO THE CLINICAL FEATURES OF SCHIZOPHRENIA, SUCH AS AGE OF ONSET, CLINICAL SUBTYPES, SYMPTOM SEVERITY, AND DRUG RESPONSE, HAVE BEEN EVALUATED AMONG DIFFERENT POPULATIONS. HOWEVER, THE RESULTS ARE STILL INCONSISTENT. FURTHER, DIFFERENT DRUGS HAVE BEEN REPORTED TO HAVE DIFFERENT EFFECTS ON BDNF PROTEIN LEVELS. A CROSS-SECTIONAL SURVEY REVEALED THAT SERUM BDNF LEVELS IN CHRONIC SCHIZOPHRENIC PATIENTS TREATED WITH CLOZAPINE EXCEEDED THOSE OF PATIENTS TREATED WITH RISPERIDONE OR WITH TYPICAL ANTIPSYCHOTICS. IN RECENT TIMES, BDNF EPIGENETIC STUDIES HAVE ALSO BEEN CONDUCTED IN CLINICAL STUDIES OF SCHIZOPHRENIA TO ADDRESS THE QUESTION OF WHY PATIENTS WITH THE SAME GENE GENOTYPE AND ALLELES HAVE DIFFERENT CLINICAL PRESENTATIONS. IN ADDITION, THE EFFECTS OF DIFFERENT ANTIPSYCHOTIC DRUGS ON GENE METHYLATION AND PROTEIN ACETYLATION HAVE ALSO BEEN REPORTED. IN CONCLUSION, MORE DATA ARE NEEDED REGARDING BDNF IN THE BRAIN AND IN PERIPHERAL BLOOD, INCLUDING PROTEIN LEVELS, SINGLE NUCLEOTIDE POLYMORPHISMS, EPIGENETIC REGULATION, AND CLINICAL DATA IN ORDER TO UNDERSTAND THE ROLE OF BDNF IN SCHIZOPHRENIA. 2013 13 6292 32 THE PRIMACY OF PSYCHOANALYTIC INTERVENTION IN RECOVERY FROM THE PSYCHOSES AND SCHIZOPHRENIAS. FUNCTIONAL CAPACITIES, SUCH AS ATTACHMENT AND AFFECT REGULATION, OBJECT RELATIONS CAPACITY, SYMBOLIC FUNCTION AND LANGUAGE DEVELOPMENT, NOW DOCUMENTED BY NEUROSCIENTIFIC RESEARCH AND EPIGENETICS, ARE REVIEWED. RESULTS FROM THIS RESEARCH, TOGETHER WITH OTHER FACTORS, ARE POSITED TO HAVE CONTRIBUTED TO EFFECTIVE CONTEMPORARY PSYCHOANALYTIC AND PSYCHOTHERAPEUTIC TREATMENTS FOR THE PSYCHOSES AND SCHIZOPHRENIAS. ETIOLOGICAL FACTORS INVOLVING THE SCHIZOPHRENIAS AND OTHER PSYCHOSES ARE CONSIDERED BOTH IN TERMS OF AN EPIGENETIC MODEL, AND IN TERMS OF HOW ETIOLOGY MAY, OR MAY NOT, AFFECT CLINICAL TREATMENT. THE LACANIAN 388 PROGRAM IS REVIEWED IN SOME DETAIL, AS ARE SEVERAL PSYCHOANALYTIC AND PSYCHOTHERAPEUTIC CLINICAL APPROACHES USED WITH THIS POPULATION OVER THE LAST SIX DECADES. ALL TREATMENTS FOCUS ON THE PRIMACY OF PSYCHOTHERAPEUTIC INTERVENTION, AND USE MEDICATIONS MINIMALLY, NOT AT ALL, OR ONLY AS INFORMED BY AN OVER-ARCHING PSYCHODYNAMIC MODEL OF TREATMENT. THE AUTHOR ARGUES THAT THERE IS NOW SUBSTANTIAL RESEARCH AND OUTCOME DATA SUGGESTING THAT THE PSYCHOSES AND SCHIZOPHRENIAS ARE NOT CHRONIC DETERIORATING CONDITIONS. RECOVERY IS OBSERVED IN MANY PSYCHOTIC AND SCHIZOPHRENIC PATIENTS TREATED WITH APPROACHES THAT FOCUS ON THE PRIMACY OF PSYCHOTHERAPEUTIC INTERVENTION. 2007 14 4206 45 METABOTROPIC GLUTAMATE 2/3 RECEPTORS AND EPIGENETIC MODIFICATIONS IN PSYCHOTIC DISORDERS: A REVIEW. SCHIZOPHRENIA AND BIPOLAR DISORDER ARE CHRONIC PSYCHIATRIC DISORDERS, BOTH CONSIDERED AS "MAJOR PSYCHOSIS"; THEY ARE THOUGHT TO SHARE SOME PATHOGENETIC FACTORS INVOLVING A DYSFUNCTIONAL GENE X ENVIRONMENT INTERACTION. ALTERATIONS IN THE GLUTAMATERGIC TRANSMISSION HAVE BEEN SUGGESTED TO BE INVOLVED IN THE PATHOGENESIS OF PSYCHOSIS. OUR GROUP DEVELOPED AN EPIGENETIC MODEL OF SCHIZOPHRENIA ORIGINATED BY PRENATAL RESTRAINT STRESS (PRS) PARADIGM IN MICE. PRS MICE DEVELOPED SOME BEHAVIORAL ALTERATIONS OBSERVED IN SCHIZOPHRENIC PATIENTS AND CLASSIC ANIMAL MODELS OF SCHIZOPHRENIA, I.E. DEFICITS IN SOCIAL INTERACTION, LOCOMOTOR ACTIVITY AND PREPULSE INHIBITION. THEY ALSO SHOWED SPECIFIC CHANGES IN PROMOTER DNA METHYLATION ACTIVITY OF GENES RELATED TO SCHIZOPHRENIA SUCH AS REELIN, BDNF AND GAD67, AND ALTERED EXPRESSION AND FUNCTION OF MGLU2/3 RECEPTORS IN THE FRONTAL CORTEX. INTERESTINGLY, BEHAVIORAL AND MOLECULAR ALTERATIONS WERE REVERSED BY TREATMENT WITH MGLU2/3 AGONISTS. BASED ON THESE FINDINGS, WE SPECULATE THAT PHARMACOLOGICAL MODULATION OF THESE RECEPTORS COULD HAVE A GREAT IMPACT ON EARLY PHASE TREATMENT OF PSYCHOSIS TOGETHER WITH THE POSSIBILITY TO MODULATE SPECIFIC EPIGENETIC KEY PROTEIN INVOLVED IN THE DEVELOPMENT OF PSYCHOSIS. IN THIS REVIEW, WE WILL DISCUSS IN MORE DETAILS THE SPECIFIC FEATURES OF THE PRS MICE AS A SUITABLE EPIGENETIC MODEL FOR MAJOR PSYCHOSIS. WE WILL THEN FOCUS ON KEY PROTEINS OF CHROMATIN REMODELING MACHINERY AS POTENTIAL TARGET FOR NEW PHARMACOLOGICAL TREATMENT THROUGH THE ACTIVATION OF METABOTROPIC GLUTAMATE RECEPTORS. 2016 15 5302 32 PROTEIN-C REACTIVE AS BIOMARKER PREDICTOR OF SCHIZOPHRENIA PHASES OF ILLNESS? A SYSTEMATIC REVIEW. BACKGROUND: SCHIZOPHRENIA IS A COMPLEX ILLNESS IN WHICH GENETIC, ENVIRONMENTAL, AND EPIGENETIC COMPONENTS HAVE BEEN IMPLICATED. HOWEVER, RECENTLY, PSYCHIATRIC DISORDERS APPEAR TO BE RELATED TO A CHRONIC INFLAMMATORY STATE, AT THE LEVEL OF SPECIFIC CEREBRAL AREAS WHICH HAVE BEEN FOUND AS WELL IMPAIRED AND RESPONSIBLE FOR SCHIZOPHRENIA SYMPTOMATOLOGY. HENCE, A ROLE OF INFLAMMATORY MEDIATORS AND CYTOKINES HAS BEEN AS WELL DEFINED. ACCORDINGLY, THE ROLE OF AN ACUTE INFLAMMATORY PHASE PROTEIN, THE C-REACTIVE PROTEIN (CRP) HAS BEEN RECENTLY INVESTIGATED. OBJECTIVE: THE OBJECTIVE OF THE PRESENT STUDY IS TO EVALUATE HOW PCR MAY REPRESENT A BIOMARKER IN SCHIZOPHRENIA, I.E. CORRELATED WITH ILLNESS PHASES AND/OR CLINICAL MANIFESTATION AND/OR PSYCHOPATHOLOGICAL SEVERITY. METHODS: A SYSTEMATIC REVIEW WAS HERE CARRIED OUT BY SEARCHING THE FOLLOWING KEYWORDS ((C-REACTIVE PROTEIN AND ((SCHIZOPHRENIA) OR (PSYCHOTIC DISORDER))) FOR THE TOPICS 'PCR' AND 'SCHIZOPHRENIA', BY USING MESH TERMS. RESULTS: AN IMMUNE DYSFUNCTION AND INFLAMMATION HAVE BEEN DESCRIBED AMONGST SCHIZOPHRENIC PATIENTS. FINDINGS REPORTED ELEVATED CRP LEVELS IN SCHIZOPHRENIA, MAINLY CORRELATED WITH THE SEVERITY OF ILLNESS AND DURING THE RECRUDESCENT PHASE. CRP LEVELS ARE HIGHER WHEN CATATONIC FEATURES, NEGATIVE SYMPTOMATOLOGY AND AGGRESSIVENESS ARE ASSOCIATED. CRP LEVELS APPEARED NOT TO BE RELATED TO SUICIDAL BEHAVIOUR AND IDEATION. CONCLUSION: CRP AND ITS BLOOD LEVELS HAVE BEEN REPORTED HIGHER AMONGST SCHIZOPHRENIC PATIENTS, BY SUGGESTING A ROLE OF INFLAMMATION IN THE PATHOGENESIS OF SCHIZOPHRENIA. FURTHER STUDIES ARE NEEDED TO BETTER UNDERSTAND IF CRP MAY BE CONSIDERED A BIOMARKER IN SCHIZOPHRENIA. 2018 16 513 26 ASSOCIATION OF SEROTONIN TRANSPORTER GENE ALUJB METHYLATION WITH MAJOR DEPRESSION, AMYGDALA RESPONSIVENESS, 5-HTTLPR/RS25531 POLYMORPHISM, AND STRESS. DNA METHYLATION PROFILES OF THE SEROTONIN TRANSPORTER GENE (SLC6A4) HAVE BEEN SHOWN TO ALTER SLC6A4 EXPRESSION, DRIVE ANTIDEPRESSANT TREATMENT RESPONSE AND MODIFY BRAIN FUNCTIONS. THIS STUDY INVESTIGATED WHETHER METHYLATION OF AN ALUJB ELEMENT IN THE SLC6A4 PROMOTOR WAS ASSOCIATED WITH MAJOR DEPRESSIVE DISORDER (MDD), AMYGDALA REACTIVITY TO EMOTIONAL FACES, 5-HTTLPR/RS25531 POLYMORPHISM, AND RECENT STRESS. MDD PATIENTS (N=122) AND HEALTHY CONTROLS (HC, N=176) UNDERWENT FMRI DURING AN EMOTIONAL FACE-MATCHING TASK. INDIVIDUAL SLC6A4 ALUJB METHYLATION PROFILES WERE ASCERTAINED AND ASSOCIATED WITH MDD, AMYGDALA REACTIVITY, 5-HTTLPR/RS25531, AND STRESS. SLC6A4 ALUJB METHYLATION WAS SIGNIFICANTLY LOWER IN MDD COMPARED TO HC AND IN STRESSED COMPARED TO LESS STRESSED PARTICIPANTS. LOWER ALUJB METHYLATION WAS PARTICULARLY FOUND IN 5-HTTLPR/RS25531 RISK ALLELE CARRIERS UNDER STRESS AND CORRELATED WITH LESS DEPRESSIVE EPISODES. FMRI ANALYSIS REVEALED A SIGNIFICANT INTERACTION OF ALUJB METHYLATION AND DIAGNOSIS IN THE AMYGDALA, WITH MDD PATIENTS SHOWING LOWER ALUJB METHYLATION ASSOCIATED WITH DECREASED AMYGDALA REACTIVITY. WHILE NO JOINT EFFECT OF ALUJB METHYLATION AND 5-HTTLPR/RS25531 EXISTED, RISK ALLELE CARRIERS SHOWED SIGNIFICANTLY INCREASED BILATERAL AMYGDALA ACTIVATION. THESE FINDINGS SUGGEST A ROLE OF SLC6A4 ALUJB METHYLATION IN MDD, AMYGDALA REACTIVITY, AND STRESS REACTION, PARTLY INTERWOVEN WITH 5-HTTLPR/RS25531 EFFECTS. PATIENTS WITH LOW METHYLATION IN CONJUNCTION WITH A SHORTER MDD HISTORY AND DECREASED AMYGDALA REACTIVITY MIGHT FEATURE A MORE STRESS-ADAPTIVE EPIGENETIC PROCESS, MAYBE VIA THEORETICALLY POSSIBLE ENDOGENOUS ANTIDEPRESSANT-LIKE EFFECTS. IN CONTRAST, PATIENTS WITH HIGHER METHYLATION MIGHT POSSIBLY SUFFER FROM IMPAIRED EPIGENETIC ADAPTION TO CHRONIC STRESS. FURTHER, THE 5-HTTLPR/RS25531 ASSOCIATION WITH AMYGDALA ACTIVATION WAS CONFIRMED IN OUR LARGE SAMPLE. 2018 17 2044 31 EPIGENETIC CLOCK ANALYSIS OF BLOOD SAMPLES IN DRUG-NAIVE FIRST-EPISODE SCHIZOPHRENIA PATIENTS. BACKGROUND: SCHIZOPHRENIA (SCZ) IS A SEVERE AND CHRONIC PSYCHIATRIC DISORDER WITH PREMATURE AGE-RELATED PHYSIOLOGICAL CHANGES. HOWEVER, NUMEROUS PREVIOUS STUDIES EXAMINED THE EPIGENETIC AGE ACCELERATION IN SCZ PATIENTS AND YIELDED INCONCLUSIVE RESULTS. IN THIS STUDY, WE PROPOSE TO EXPLORE THE EPIGENETIC AGE ACCELERATION IN DRUG-NAIVE FIRST-EPISODE SCZ (FSCZ) PATIENTS AND INVESTIGATE WHETHER EPIGENETIC AGE ACCELERATION IS ASSOCIATED WITH ANTIPSYCHOTIC TREATMENT, PSYCHOTIC SYMPTOMS, COGNITION, AND SUBCORTICAL VOLUMES. METHODS: WE ASSESSED THE EPIGENETIC AGE IN 38 DRUG-NAIVE FSCZ PATIENTS AND 38 HEALTHY CONTROLS BY USING THREE INDEPENDENT CLOCKS, INCLUDING HORVATH, HANNUM AND LEVINE ALGORITHMS. THE EPIGENETIC AGE MEASUREMENTS IN SCZ PATIENTS WERE REPEATED AFTER RECEIVING 8 WEEKS RISPERIDONE MONOTHERAPY. RESULTS: OUR FINDINGS SHOWED SIGNIFICANTLY POSITIVE CORRELATIONS BETWEEN EPIGENETIC AGES ASSESSED BY THREE CLOCKS AND CHRONOLOGICAL AGE IN BOTH FSCZ PATIENTS AND HEALTHY CONTROLS. COMPARED WITH HEALTHY CONTROLS, DRUG-NAIVE FSCZ PATIENTS HAVE A SIGNIFICANT EPIGENETIC AGE DECELERATION IN HORVATH CLOCK (P = 0.01), BUT NOT IN HANNUM CLOCK (P = 0.07) AND LEVINE CLOCK (P = 0.43). THE EPIGENETIC AGES OF HANNUM CLOCK (P = 0.002) AND LEVINE CLOCK (P = 0.01) WERE SIGNIFICANTLY ACCELERATED IN SCZ PATIENTS AFTER 8-WEEK RISPERIDONE TREATMENT. HOWEVER, NO SIGNIFICANT ASSOCIATIONS BETWEEN EPIGENETIC AGE ACCELERATION AND PSYCHOTIC SYMPTOMS, COGNITIVE FUNCTION, AS WELL AS SUBCORTICAL VOLUMES WERE OBSERVED IN FSCZ PATIENTS. CONCLUSION: THESE RESULTS DEMONSTRATE THAT DISTINCT EPIGENETIC CLOCKS ARE SENSITIVE TO DIFFERENT ASPECTS OF AGING PROCESS. FURTHER INVESTIGATIONS WITH COMPREHENSIVE EPIGENETIC CLOCK ANALYSES AND LARGE SAMPLES ARE REQUIRED TO CONFIRM OUR FINDINGS. 2023 18 1554 40 DNA METHYLATION LEVELS OF RELN PROMOTER REGION IN ULTRA-HIGH RISK, FIRST EPISODE AND CHRONIC SCHIZOPHRENIA COHORTS OF SCHIZOPHRENIA. THE ESSENTIAL ROLE OF THE REELIN GENE (RELN) DURING BRAIN DEVELOPMENT MAKES IT A PROMINENT CANDIDATE IN HUMAN EPIGENETIC STUDIES OF SCHIZOPHRENIA. PREVIOUS LITERATURE HAS REPORTED DIFFERING LEVELS OF DNA METHYLATION (DNAM) IN PATIENTS WITH PSYCHOSIS. THEREFORE, THIS STUDY AIMED TO (1) EXAMINE AND COMPARE RELN DNAM LEVELS IN SUBJECTS AT DIFFERENT STAGES OF PSYCHOSIS CROSS-SECTIONALLY, (2) ANALYSE THE EFFECT OF ANTIPSYCHOTICS (AP) ON DNAM, AND (3) EVALUATE THE EFFECTIVENESS AND APPLICABILITY OF RELN PROMOTER DNAM AS A POSSIBLE BIOLOGICAL-BASED MARKER FOR SYMPTOM SEVERITY IN PSYCHOSIS.. THE STUDY COHORT CONSISTED OF 56 HEALTHY CONTROLS, 87 ULTRA-HIGH RISK (UHR) INDIVIDUALS, 26 FIRST-EPISODE (FE) PSYCHOSIS INDIVIDUALS AND 30 CHRONIC SCHIZOPHRENIA (CS) INDIVIDUALS. THE POSITIVE AND NEGATIVE SYNDROME SCALE (PANSS) WAS USED TO ASSESS SCHIZOPHRENIA SEVERITY. AFTER PYROSEQUENCING SELECTED CPG SITES OF PERIPHERAL BLOOD, THE AVERAGE MEAN DNAM LEVELS WERE COMPARED AMONGST THE 4 SUBGROUPS. OUR RESULTS SHOWED DIFFERING LEVELS OF DNAM, WITH UHR HAVING THE LOWEST (7.72 +/- 0.19) WHILE THE CS HAD THE HIGHEST LEVELS (HC: 8.78 +/- 0.35; FE: 7.75 +/- 0.37; CS: 8.82 +/- 0.48). SIGNIFICANTLY HIGHER AVERAGE MEAN DNAM LEVELS WERE FOUND IN CS SUBJECTS ON AP (9.12 +/- 0.61) COMPARED TO UHR WITHOUT MEDICATION (UHR(-)) (7.39 +/- 0.18). A SIGNIFICANT ASSOCIATION WAS ALSO OBSERVED BETWEEN THE AVERAGE MEAN DNAM OF FE AND PANSS NEGATIVE SYMPTOM FACTOR (R(2) = 0.237, SS = -0.401, *P = 0.033). IN CONCLUSION, OUR FINDINGS SUGGESTED DIFFERENT LEVELS OF DNAM FOR SUBJECTS AT DIFFERENT STAGES OF PSYCHOSIS. THOSE SUBJECTS THAT TOOK AP HAVE DIFFERENT DNAM LEVELS. THERE WERE SIGNIFICANT ASSOCIATIONS BETWEEN FE DNAM AND NEGATIVE PANSS SCORES. WITH MORE FUTURE EXPERIMENTS AND ON LARGER COHORTS, THERE MAY BE POTENTIAL USE OF DNAM OF THE RELN GENE AS ONE OF THE GENES FOR THE BIOLOGICAL-BASED MARKER FOR SYMPTOM SEVERITY IN PSYCHOSIS. 2022 19 4828 39 OLANZAPINE INDUCED DNA METHYLATION CHANGES SUPPORT THE DOPAMINE HYPOTHESIS OF PSYCHOSIS. BACKGROUND: THE DOPAMINE (DA) HYPOTHESIS OF SCHIZOPHRENIA PROPOSES THE MENTAL ILLNESS IS CAUSED BY EXCESSIVE TRANSMISSION OF DOPAMINE IN SELECTED BRAIN REGIONS. MULTIPLE LINES OF EVIDENCE, INCLUDING BLOCKAGE OF DOPAMINE RECEPTORS BY ANTIPSYCHOTIC DRUGS THAT ARE USED TO TREAT SCHIZOPHRENIA, SUPPORT THE HYPOTHESIS. HOWEVER, THE DOPAMINE D2 RECEPTOR (DRD2) BLOCKADE CANNOT EXPLAIN SOME IMPORTANT ASPECTS OF THE THERAPEUTIC EFFECT OF ANTIPSYCHOTIC DRUGS. IN THIS STUDY, WE HYPOTHESIZED THAT ANTIPSYCHOTIC DRUGS COULD AFFECT THE TRANSCRIPTION OF GENES IN THE DA PATHWAY BY ALTERING THEIR EPIGENETIC PROFILE. METHODS: TO TEST THIS HYPOTHESIS, WE EXAMINED THE EFFECT OF OLANZAPINE, A COMMONLY USED ATYPICAL ANTIPSYCHOTIC DRUG, ON THE DNA METHYLATION STATUS OF GENES FROM DA NEUROTRANSMISSION IN THE BRAIN AND LIVER OF RATS. GENOMIC DNA ISOLATED FROM HIPPOCAMPUS, CEREBELLUM, AND LIVER OF OLANZAPINE TREATED (N = 2) AND CONTROL (N = 2) RATS WERE ANALYZED USING RAT SPECIFIC METHYLATION ARRAYS. RESULTS: OUR RESULTS SHOW THAT OLANZAPINE CAUSES METHYLATION CHANGES IN GENES ENCODING FOR DA RECEPTORS (DOPAMINE D1 RECEPTOR, DOPAMINE D2 RECEPTOR AND DOPAMINE D5 RECEPTOR), A DA TRANSPORTER (SOLUTE CARRIER FAMILY 18 MEMBER 2), A DA SYNTHESIS (DIFFERENTIAL DISPLAY CLONE 8), AND A DA METABOLISM (CATECHOL-O-METHYLTRANSFERASE). WE ASSESSED A TOTAL OF 40 GENES IN THE DA PATHWAY AND FOUND 19 TO BE DIFFERENTIALLY METHYLATED BETWEEN OLANZAPINE TREATED AND CONTROL RATS. MOST (17/19) GENES SHOWED AN INCREASE IN METHYLATION, IN THEIR PROMOTER REGIONS WITH IN SILICO ANALYSIS STRONGLY INDICATING A FUNCTIONAL POTENTIAL TO SUPPRESS TRANSCRIPTION IN THE BRAIN. CONCLUSION: OUR RESULTS SUGGEST THAT CHRONIC OLANZAPINE MAY REDUCE DA ACTIVITY BY ALTERING GENE METHYLATION. IT MAY ALSO EXPLAIN THE DELAYED THERAPEUTIC EFFECT OF ANTIPSYCHOTICS, WHICH OCCURS DESPITE RAPID DOPAMINE BLOCKADE. FURTHERMORE, GIVEN THE COMMON NATURE OF EPIGENETIC VARIATION, THIS LENDS INSIGHT INTO THE DIFFERENTIAL THERAPEUTIC RESPONSE OF PSYCHOTIC PATIENTS WHO DISPLAY ADEQUATE BLOCKAGE OF DOPAMINE RECEPTORS. 2013 20 881 33 CHRONIC CLOZAPINE TREATMENT RESTRAINS VIA HDAC2 THE PERFORMANCE OF MGLU2 RECEPTOR AGONISM IN A RODENT MODEL OF ANTIPSYCHOTIC ACTIVITY. PRECLINICAL FINDINGS IN RODENT MODELS POINTED TOWARD ACTIVATION OF METABOTROPIC GLUTAMATE 2/3 (MGLU2/3) RECEPTORS AS A NEW PHARMACOLOGICAL APPROACH TO TREAT PSYCHOSIS. HOWEVER, MORE RECENT STUDIES FAILED TO SHOW CLINICAL EFFICACY OF MGLU2/3 RECEPTOR AGONISM IN SCHIZOPHRENIA PATIENTS. WE PREVIOUSLY PROPOSED THAT LONG-TERM ANTIPSYCHOTIC MEDICATION RESTRICTED THE THERAPEUTIC EFFECTS OF THESE GLUTAMATERGIC AGENTS. HOWEVER, LITTLE IS KNOWN ABOUT THE MOLECULAR MECHANISM UNDERLYING THE POTENTIAL REPERCUSSION OF PREVIOUS ANTIPSYCHOTIC EXPOSURE ON THE THERAPEUTIC PERFORMANCE OF MGLU2/3 RECEPTOR AGONISTS. HERE WE SHOW THAT THIS MALADAPTIVE EFFECT OF ANTIPSYCHOTIC TREATMENT IS MEDIATED MOSTLY VIA HISTONE DEACETYLASE 2 (HDAC2). CHRONIC TREATMENT WITH THE ANTIPSYCHOTIC CLOZAPINE LED TO A DECREASE IN MOUSE FRONTAL CORTEX MGLU2 MRNA, AN EFFECT THAT REQUIRED EXPRESSION OF BOTH HDAC2 AND THE SEROTONIN 5-HT(2A) RECEPTOR. THIS TRANSCRIPTIONAL ALTERATION OCCURRED IN ASSOCIATION WITH HDAC2-DEPENDENT REPRESSIVE HISTONE MODIFICATIONS AT THE MGLU2 PROMOTER. WE FOUND THAT CHRONIC CLOZAPINE TREATMENT DECREASED VIA HDAC2 THE CAPABILITIES OF THE MGLU2/3 RECEPTOR AGONIST LY379268 TO ACTIVATE G-PROTEINS IN THE FRONTAL CORTEX OF MICE. CHRONIC CLOZAPINE TREATMENT BLUNTED THE ANTIPSYCHOTIC-RELATED BEHAVIORAL EFFECTS OF LY379268, AN EFFECT THAT WAS NOT OBSERVED IN HDAC2 KNOCKOUT MICE. MORE IMPORTANTLY, CO-ADMINISTRATION OF THE CLASS I AND II HDAC INHIBITOR SAHA (VORINOSTAT) PRESERVED THE ANTIPSYCHOTIC PROFILE OF LY379268 AND FRONTAL CORTEX MGLU2/3 RECEPTOR DENSITY IN WILD-TYPE MICE. THESE FINDINGS RAISE CONCERNS ON THE DESIGN OF PREVIOUS CLINICAL STUDIES WITH MGLU2/3 AGONISTS, PROVIDING THE RATIONALE FOR THE DEVELOPMENT OF HDAC2 INHIBITORS AS A NEW EPIGENETIC-BASED APPROACH TO IMPROVE THE CURRENTLY LIMITED RESPONSE TO TREATMENT WITH GLUTAMATERGIC ANTIPSYCHOTICS. 2019