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1.
N Engl J Med ; 382(20): 1926-1932, 2020 05 14.
Article in English | MEDLINE | ID: mdl-32402162

ABSTRACT

We report the implantation of patient-derived midbrain dopaminergic progenitor cells, differentiated in vitro from autologous induced pluripotent stem cells (iPSCs), in a patient with idiopathic Parkinson's disease. The patient-specific progenitor cells were produced under Good Manufacturing Practice conditions and characterized as having the phenotypic properties of substantia nigra pars compacta neurons; testing in a humanized mouse model (involving peripheral-blood mononuclear cells) indicated an absence of immunogenicity to these cells. The cells were implanted into the putamen (left hemisphere followed by right hemisphere, 6 months apart) of a patient with Parkinson's disease, without the need for immunosuppression. Positron-emission tomography with the use of fluorine-18-L-dihydroxyphenylalanine suggested graft survival. Clinical measures of symptoms of Parkinson's disease after surgery stabilized or improved at 18 to 24 months after implantation. (Funded by the National Institutes of Health and others.).


Subject(s)
Dopaminergic Neurons/cytology , Induced Pluripotent Stem Cells/transplantation , Parkinson Disease/therapy , Pars Compacta/cytology , Aged , Animals , Basal Ganglia/diagnostic imaging , Basal Ganglia/metabolism , Cell Differentiation , Disease Models, Animal , Dopaminergic Neurons/metabolism , Dopaminergic Neurons/transplantation , Follow-Up Studies , Humans , Induced Pluripotent Stem Cells/immunology , Male , Mice , Mice, SCID , Parkinson Disease/diagnostic imaging , Positron-Emission Tomography , Putamen/diagnostic imaging , Tomography, X-Ray Computed , Transplantation, Autologous , Transplantation, Homologous
2.
Mol Psychiatry ; 26(10): 5702-5714, 2021 10.
Article in English | MEDLINE | ID: mdl-33863993

ABSTRACT

Altered energy metabolism has been implicated both in aging and the pathogenesis of late-onset Alzheimer's disease (LOAD). However, it is unclear which anomalies are acquired phenotypes and which are inherent and predispose to disease. We report that neural progenitor cells and astrocytes differentiated from LOAD patient-derived induced pluripotent stem cells exhibit multiple inter-related bioenergetic alterations including: changes in energy production by mitochondrial respiration versus glycolysis, as a consequence of alterations in bioenergetic substrate processing and transfer of reducing agents, reduced levels of NAD/NADH, diminished glucose uptake and response rates to insulin (INS)/IGF-1 signaling, decreased INS receptor and glucose transporter 1 densities, and changes in the metabolic transcriptome. Our data confirm that LOAD is a "multi-hit" disorder and provide evidence for innate inefficient cellular energy management in LOAD that likely predisposes to neurodegenerative disease with age. These processes may guide the development and testing of diagnostic procedures or therapeutic agents.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Aging , Brain , Energy Metabolism , Humans
4.
Mol Psychiatry ; 25(11): 2873-2888, 2020 11.
Article in English | MEDLINE | ID: mdl-31019265

ABSTRACT

Schizophrenia (SCZ) is a neurodevelopmental disorder. Thus, studying pathogenetic mechanisms underlying SCZ requires studying the development of brain cells. Cortical interneurons (cINs) are consistently observed to be abnormal in SCZ postmortem brains. These abnormalities may explain altered gamma oscillation and cognitive function in patients with SCZ. Of note, currently used antipsychotic drugs ameliorate psychosis, but they are not very effective in reversing cognitive deficits. Characterizing mechanisms of SCZ pathogenesis, especially related to cognitive deficits, may lead to improved treatments. We generated homogeneous populations of developing cINs from 15 healthy control (HC) iPSC lines and 15 SCZ iPSC lines. SCZ cINs, but not SCZ glutamatergic neurons, show dysregulated Oxidative Phosphorylation (OxPhos) related gene expression, accompanied by compromised mitochondrial function. The OxPhos deficit in cINs could be reversed by Alpha Lipoic Acid/Acetyl-L-Carnitine (ALA/ALC) but not by other chemicals previously identified as increasing mitochondrial function. The restoration of mitochondrial function by ALA/ALC was accompanied by a reversal of arborization deficits in SCZ cINs. OxPhos abnormality, even in the absence of any circuit environment with other neuronal subtypes, appears to be an intrinsic deficit in SCZ cINs.


Subject(s)
Induced Pluripotent Stem Cells , Interneurons/metabolism , Interneurons/pathology , Mitochondria/metabolism , Mitochondria/pathology , Schizophrenia/pathology , Cell Line , Humans , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/pathology , Male
5.
Psychother Psychosom ; 90(6): 373-385, 2021.
Article in English | MEDLINE | ID: mdl-34233335

ABSTRACT

Standard diagnostic systems, the predominantly categorical DSM-5 and ICD-11, have limitations in validity, utility, and predictive and descriptive power. For psychotic disorders, these issues were partly addressed in current versions, but additional modifications are thought to be needed. Changes should be evidence based. We reviewed categorical, modified-categorical, and continuum-based models versus factor-based models of psychosis. Factors are clusters of symptoms or single prominent aspects of illness. Consistent evidence from studies of the genetics, pathobiology, and clinical presentation of psychotic disorders all support an underlying structure of factors, not categories, as best characterizing psychoses. Factors are not only the best fit but also comprehensive, as they can encompass any key feature of illness, including symptoms and course, as well as determinants of risk or response. Factors are inherently dimensional, even multidimensional, as are the psychoses themselves, and they provide the detail needed for either grouping or distinguishing patients for treatment decisions. The tools for making factor-based diagnoses are available, reliable, and concordant with actual practices used for clinical assessments. If needed, factors can be employed to create categories similar to those in current use. In addition, they can be used to define unique groupings of patients relevant to specific treatments or studies of the psychoses. Lastly, factor-based classifications are concordant with other comprehensive approaches to psychiatric nosology, including personalized (precision treatment) models and hierarchical models, both of which are currently being explored. Factors might be considered as the right primary structural choice for future versions of standard diagnostic systems, both DSM and ICD.


Subject(s)
Psychotic Disorders , Diagnostic and Statistical Manual of Mental Disorders , Humans , International Classification of Diseases , Psychotic Disorders/diagnosis , Psychotic Disorders/therapy
6.
Mol Psychiatry ; 24(10): 1513-1522, 2019 10.
Article in English | MEDLINE | ID: mdl-29523870

ABSTRACT

Patients with psychotic disorders are at high risk for type 2 diabetes mellitus, and there is increasing evidence that patients display glucose metabolism abnormalities before significant antipsychotic medication exposure. In the present study, we examined insulin action by quantifying insulin sensitivity in first-episode psychosis (FEP) patients and unaffected siblings, compared to healthy individuals, using a physiological-based model and comprehensive assessment battery. Twenty-two unaffected siblings, 18 FEP patients, and 15 healthy unrelated controls were evaluated using a 2-h oral glucose tolerance test (OGTT), with 7 samples of plasma glucose and serum insulin concentration measurements. Insulin sensitivity was quantified using the oral minimal model method. Lipid, leptin, free fatty acids, and inflammatory marker levels were also measured. Anthropometric, nutrient, and activity assessments were conducted; total body composition and fat distribution were determined using whole-body dual-energy X-ray absorptiometry. Insulin sensitivity significantly differed among groups (F = 6.01 and 0.004), with patients and siblings showing lower insulin sensitivity, compared to controls (P = 0.006 and 0.002, respectively). Body mass index, visceral adipose tissue area (cm2), lipids, leptin, free fatty acids, inflammatory markers, and activity ratings were not significantly different among groups. There was a significant difference in nutrient intake with lower total kilocalories/kilogram body weight in patients, compared to siblings and controls. Overall, the findings suggest that familial abnormal glucose metabolism or a primary insulin signaling pathway abnormality is related to risk for psychosis, independent of disease expression and treatment effects. Future studies should examine underlying biological mechanisms of insulin signaling abnormalities in psychotic disorders.


Subject(s)
Diabetes Mellitus, Type 2/etiology , Insulin/metabolism , Psychotic Disorders/metabolism , Adult , Anthropometry , Antipsychotic Agents/therapeutic use , Blood Glucose/analysis , Blood Glucose/metabolism , Body Composition , Body Mass Index , Diabetes Mellitus, Type 2/metabolism , Female , Glucose/metabolism , Humans , Insulin/blood , Insulin Resistance/physiology , Leptin/blood , Male , Psychotic Disorders/complications , Siblings , Signal Transduction/physiology , Triglycerides/blood
8.
J Neurosci ; 37(32): 7656-7668, 2017 08 09.
Article in English | MEDLINE | ID: mdl-28674176

ABSTRACT

Stress plays a critical role in the neurobiology of mood and anxiety disorders. Sleep and circadian rhythms are affected in many of these conditions. Here we examined the effects of chronic social defeat stress (CSDS), an ethological form of stress, on sleep and circadian rhythms. We exposed male mice implanted with wireless telemetry transmitters to a 10 day CSDS regimen known to produce anhedonia (a depressive-like effect) and social avoidance (an anxiety-like effect). EEG, EMG, body temperature, and locomotor activity data were collected continuously during the CSDS regimen and a 5 day recovery period. CSDS affected numerous endpoints, including paradoxical sleep (PS) and slow-wave sleep (SWS), as well as the circadian rhythmicity of body temperature and locomotor activity. The magnitude of the effects increased with repeated stress, and some changes (PS bouts, SWS time, body temperature, locomotor activity) persisted after the CSDS regimen had ended. CSDS also altered mRNA levels of the circadian rhythm-related gene mPer2 within brain areas that regulate motivation and emotion. Administration of the κ-opioid receptor (KOR) antagonist JDTic (30 mg/kg, i.p.) before CSDS reduced stress effects on both sleep and circadian rhythms, or hastened their recovery, and attenuated changes in mPer2 Our findings show that CSDS produces persistent disruptions in sleep and circadian rhythmicity, mimicking attributes of stress-related conditions as they appear in humans. The ability of KOR antagonists to mitigate these disruptions is consistent with previously reported antistress effects. Studying homologous endpoints across species may facilitate the development of improved treatments for psychiatric illness.SIGNIFICANCE STATEMENT Stress plays a critical role in the neurobiology of mood and anxiety disorders. We show that chronic social defeat stress in mice produces progressive alterations in sleep and circadian rhythms that resemble features of depression as it appears in humans. Whereas some of these alterations recover quickly upon cessation of stress, others persist. Administration of a kappa-opioid receptor (KOR) antagonist reduced stress effects or hastened recovery, consistent with the previously reported antistress effects of this class of agents. Use of endpoints, such as sleep and circadian rhythm, that are homologous across species will facilitate the implementation of translational studies that better predict clinical outcomes in humans, improve the success of clinical trials, and facilitate the development of more effective therapeutics.


Subject(s)
Circadian Rhythm/physiology , Piperidines/pharmacology , Receptors, Opioid, kappa/antagonists & inhibitors , Receptors, Opioid, kappa/physiology , Sleep/physiology , Stress, Psychological/physiopathology , Tetrahydroisoquinolines/pharmacology , Animals , Circadian Rhythm/drug effects , Male , Mice , Mice, Inbred C57BL , Piperidines/therapeutic use , Random Allocation , Sleep/drug effects , Social Behavior , Stress, Psychological/drug therapy , Stress, Psychological/psychology , Tetrahydroisoquinolines/therapeutic use
9.
J Proteome Res ; 16(2): 481-493, 2017 02 03.
Article in English | MEDLINE | ID: mdl-28152600

ABSTRACT

We undertook an unbiased metabolite profiling of fibroblasts from schizophrenia patients and healthy controls to identify metabolites and pathways that are dysregulated in disease, seeking to gain new insights into the disease biology of schizophrenia and to discover potential disease-related biomarkers. We measured polar and nonpolar metabolites in the fibroblasts under normal conditions and under two stressful physiological perturbations: growth in low-glucose media and exposure to the steroid hormone dexamethasone. We found that metabolites that were significantly different between schizophrenia and control subjects showed separation of the two groups by partial least-squares discriminant analysis methods. This separation between schizophrenia and healthy controls was more robust with metabolites identified under the perturbation conditions. The most significant individual metabolite differences were also found in the perturbation experiments. Metabolites that were significantly different between schizophrenia and healthy controls included a number of plasmalogens and phosphatidylcholines. We present these results in the context of previous reports of metabolic profiling of brain tissue and plasma in schizophrenia. These results show the applicability of metabolite profiling under stressful perturbations to reveal cellular pathways that may be involved in disease biology.


Subject(s)
Fibroblasts/metabolism , Metabolome , Phosphatidylcholines/metabolism , Plasmalogens/metabolism , Schizophrenia/metabolism , Stress, Physiological , Adult , Antipsychotic Agents/therapeutic use , Biomarkers/metabolism , Case-Control Studies , Culture Media/pharmacology , Dexamethasone/pharmacology , Discriminant Analysis , Female , Fibroblasts/drug effects , Fibroblasts/pathology , Glucocorticoids/pharmacology , Glucose/deficiency , Glucose/pharmacology , Humans , Least-Squares Analysis , Male , Middle Aged , Primary Cell Culture , Schizophrenia/drug therapy , Schizophrenia/pathology
10.
J Neurogenet ; 30(3-4): 297-305, 2016.
Article in English | MEDLINE | ID: mdl-27627024

ABSTRACT

Cholinergic dysfunction contributes to cognitive deficits in schizophrenia. The atypical antipsychotic clozapine improves cognition in patients with schizophrenia, possibly through modulation of the cholinergic system. However, little is known about specific underlying mechanisms. We investigated the acute and chronic effects of clozapine on cholinergic synaptic transmission in cultured superior cervical ganglion (SCG) neurons. Spontaneous excitatory postsynaptic currents (sEPSCs) were detected and were reversibly inhibited by the nicotinic receptor antagonist d-tubocurarine, confirming that the synaptic responses were primarily mediated by nicotinic receptors. Bath application of clozapine at therapeutic concentrations rapidly and reversely inhibited both the amplitude and frequency of sEPSCs in a concentration-dependent manner, without changing either rise or decay time, suggesting that clozapine effects have both presynaptic and postsynaptic origins. The acute effects of clozapine on sEPSCs were recapitulated by chronic treatment of SCG cultures with similar concentrations of clozapine, as clozapine treatment for 4 d reduced the frequency and amplitude of sEPSCs without affecting their kinetics. Cell survival analysis indicated that SCG neuron cell counts after chronic clozapine treatment were comparable to the control group. These results demonstrate that therapeutic concentrations of clozapine suppress nicotinic synaptic transmission in SCG cholinergic synapses, a simple in vitro preparation of cholinergic transmission.


Subject(s)
Antipsychotic Agents/pharmacology , Clozapine/pharmacology , Neurons/drug effects , Synaptic Transmission/drug effects , Animals , Cells, Cultured , Excitatory Postsynaptic Potentials/drug effects , Mice , Superior Cervical Ganglion
11.
PLoS Genet ; 9(2): e1003313, 2013.
Article in English | MEDLINE | ID: mdl-23468647

ABSTRACT

We report a genome-wide RNA interference (RNAi) screen for Suppressors of Clozapine-induced Larval Arrest (scla genes) in Caenorhabditis elegans, the first genetic suppressor screen for antipsychotic drug (APD) targets in an animal. The screen identifies 40 suppressors, including the α-like nicotinic acetylcholine receptor (nAChR) homolog acr-7. We validate the requirement for acr-7 by showing that acr-7 knockout suppresses clozapine-induced larval arrest and that expression of a full-length translational GFP fusion construct rescues this phenotype. nAChR agonists phenocopy the developmental effects of clozapine, while nAChR antagonists partially block these effects. ACR-7 is strongly expressed in the pharynx, and clozapine inhibits pharyngeal pumping. acr-7 knockout and nAChR antagonists suppress clozapine-induced inhibition of pharyngeal pumping. These findings suggest that clozapine activates ACR-7 channels in pharyngeal muscle, leading to tetanus of pharyngeal muscle with consequent larval arrest. No APDs are known to activate nAChRs, but a number of studies indicate that α7-nAChR agonists may prove effective for the treatment of psychosis. α-like nAChR signaling is a mechanism through which clozapine may produce its therapeutic and/or toxic effects in humans, a hypothesis that could be tested following identification of the mammalian ortholog of C. elegans acr-7.


Subject(s)
Antipsychotic Agents , Caenorhabditis elegans , RNA Interference , Receptors, Nicotinic , Animals , Antipsychotic Agents/metabolism , Biomarkers, Pharmacological/metabolism , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , Clozapine/pharmacology , Gene Knockout Techniques , Genome , Humans , Larva/drug effects , Molecular Targeted Therapy , Nicotinic Agonists/metabolism , Receptors, Nicotinic/genetics , Receptors, Nicotinic/metabolism , Signal Transduction/drug effects , alpha7 Nicotinic Acetylcholine Receptor
12.
J Int Neuropsychol Soc ; 21(6): 468-72, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26154947

ABSTRACT

Given the substantial overlap in cognitive dysfunction between bipolar disorder (BD) and schizophrenia (SZ), we examined the utility of the MATRICS Consensus Cognitive Battery (MCCB)-developed for use in SZ-for the measurement of cognition in patients with BD with psychosis (BDP) and its association with community functioning. The MCCB, Multnomah Community Ability Scale, and measures of clinical symptoms were administered to participants with BDP (n=56), SZ (n=37), and healthy controls (HC) (n=57). Groups were compared on clinical and cognitive measures; linear regressions examined associations between MCCB and community functioning. BDP and SZ groups performed significantly worse than HC on most neurocognitive domains; BDP and HC did not differ on Social Cognition. Patients with BDP performed better than patients with SZ on most cognitive measures, although groups only differed on social cognition, working memory, verbal memory, and the composite after controlling for clinical variables. MCCB was not associated with community functioning. The MCCB is an appropriate measure of neurocognition in BDP but does not appear to capture social cognitive deficits in this population. The addition of appropriate social cognitive measures is recommended.


Subject(s)
Bipolar Disorder/complications , Cognition Disorders/etiology , Schizophrenia/complications , Schizophrenic Psychology , Adult , Analysis of Variance , Cognition Disorders/diagnosis , Consensus , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Psychiatric Status Rating Scales , Young Adult
13.
J Nerv Ment Dis ; 203(1): 37-42, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25503785

ABSTRACT

Both nonaffective and affective psychoses are associated with deficits in social functioning across the course of the illness. However, it is not clear how social functioning varies among diagnostic groups as a function of age. The current study examined the relationship between social functioning and age in schizophrenia (SZ), schizoaffective disorder (SZA), and psychotic bipolar disorder (PBD). We found that individuals with PBD had the highest functioning, whereas individuals with SZ had the poorest. The functioning of individuals with SZA fell in between those of other groups. We also found that older ages were associated with poorer functioning. Although there was not a significant diagnostic group by age interaction, visual inspection of our data suggests a subtly steeper trajectory of decline in PBD. Overall, these results indicate that early interventions targeting social functioning may benefit individuals with either non-affective or affective psychoses to slow a projected decline.


Subject(s)
Bipolar Disorder/physiopathology , Psychotic Disorders/physiopathology , Schizophrenia/physiopathology , Social Behavior , Social Support , Adolescent , Adult , Age Factors , Aged , Humans , Male , Middle Aged , Young Adult
14.
Article in English | MEDLINE | ID: mdl-26492891

ABSTRACT

The research performance of the single-item self-rating In general, would you say your health is: excellent, very good, good, fair, or poor? was evaluated relative to the SF-36 General Health Scale that contains this item, using data for a sample of psychiatric outpatients who had co-occurring chronic physical conditions (N = 177). The scale was more robust than the single-item in cross-sectional validity tests and for predicting 2-year outcomes, but the single-item had stronger discriminant validity as a measure of physical health, especially in post-baseline analyses. Single-item and scale were both sensitive enough to detect change in perceived health over 2 years and a conditional experimental effect on health self-perceptions in a randomized trial. These findings demonstrate that a global single-item can be as valid, reliable, and sensitive as a multi-item scale for longitudinal research purposes, even if the scale performs better in cross-sectional surveys or as a screening measure.

15.
Psychiatr Q ; 86(4): 505-19, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25636496

ABSTRACT

This pilot study tested the acceptability and usability of a prototype app designed to promote the physical well-being of adults with psychiatric disorders. The application under evaluation, WellWave, promoted walking as a physical exercise, and offered a variety of supportive non-physical activities, including confidential text-messaging with peer staff, and a digital library of readings and videos on recovery from psychiatric illness. Study participants engaged strongly in the app throughout the 4-week study, showing a 94 % mean daily usage rate, and a 73 % mean response rate across all electronic messages and prompts, which approximates the gold standard of 75 % for momentary ecological assessment studies. Seven of the ten study participants averaged two or more walks per week, beginning with 5-min walks and ending with walks lasting 20 min or longer. This responsiveness to the walking prompts, and the overall high rate of engagement in other app features, suggest that adults with psychiatric conditions would welcome and benefit from similar smartphone interventions that promote healthy behaviours in life domains other than exercise. Pilot study results also suggest that smartphone applications can be useful as research tools in the development and testing of theories and practical strategies for encouraging healthy lifestyles. Participants were prompted periodically to rate their own health quality, perceived control over their health, and stage-of-change in adopting a walking routine, and these electronic self-ratings showed acceptable concurrent and discriminant validity, with all participants reporting moderate to high motivation to exercise by the end of the study.


Subject(s)
Health Behavior , Health Promotion , Smartphone , Adult , Feedback, Psychological , Female , Humans , Male , Mental Disorders , Middle Aged , Pilot Projects , Quality of Life , Self Report , Text Messaging , Walking , Young Adult
16.
Am J Med Genet B Neuropsychiatr Genet ; 168B(3): 151-61, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25740047

ABSTRACT

Several event-related potentials (ERP), including P3, sensory gating (P50), and gamma oscillation, are robustly impaired in patients with schizophrenia (SCZ) and bipolar disorder (BIP). Although these ERPs are known to be heritable, little is known about the specific genetic loci involved and the degree to which they overlap with loci influencing mood and psychotic disorders. In the present study, we conducted GWAS to a) identify common variants associated with ERP endophenotypes, and b) construct polygenic risk scores (PRS) to examine overlap between genetic components of ERPs and mood and psychotic disorders. The sample consisted of 271 patients with SCZ or psychotic BIP diagnosis and 128 controls for whom ERP and genomewide data were available. GWAS were conducted using the full sample. PRS, derived from the Psychiatric Genomics Consortium (PGC) analyses of SCZ, BIP, and major depressive disorder were applied to each ERP phenotype. We identified a region on chromosome 14 that was significantly associated with sensory gating (peak SNP rs10132223, P = 1.27 × 10(-9) ). This locus has not been previously associated with psychotic illness in PGC-GWAS. In the PRS analyses, patients with a higher load of SCZ risk alleles had reduced gamma response whereas patients with a higher load of BIP risk alleles had smaller P3 amplitude. We observed a genomewide significant locus on chromosome 14 for P50. This locus may influence P50 but not psychotic illness. Among patients with psychotic illness, PRS results indicated genetic overlap between SCZ loci and gamma oscillation and between BIP loci and P3 amplitude.


Subject(s)
Bipolar Disorder/genetics , Bipolar Disorder/pathology , Electrophysiology/methods , Genome, Human , Genome-Wide Association Study , Schizophrenia/genetics , Schizophrenia/pathology , Adult , Endophenotypes , Female , Follow-Up Studies , Genetic Predisposition to Disease , Humans , Male , Prognosis
17.
J Neurogenet ; 28(1-2): 86-97, 2014.
Article in English | MEDLINE | ID: mdl-24564792

ABSTRACT

The molecular mechanisms of action of antipsychotic drugs (APDs) are not fully understood. Here, we characterize phenotypes of missense and knockout mutations in the Caenorhabditis elegans transient receptor potential melastatin (TRPM) channel ortholog gtl-2, a candidate APD target identified in a genome-wide RNAi (RNA interference) screen for Suppressors of Clozapine-induced Larval Arrest (scla genes). We then employ the developmental phenotypes of gtl-2(lf) mutants to validate our previous gtl-2(RNAi) result. GTL-2 acts in the excretory canal cell to regulate Mg(2+) homeostasis. Using exc (excretory canal abnormal) gene mutants, we demonstrate that excretory canal cell function is necessary for clozapine-induced developmental delay and lethality. Moreover, cell-specific promoter-driven expression studies reveal that GTL-2 function in the excretory canal cell is important for its role in the SCLA phenotype. We then investigate the mechanism by which GTL-2 function in the excretory canal cell impacts clozapine-induced phenotypes. gtl-2(lf) mutations cause hypermagnesemia, and we show that exposure of the wild-type strain to high Mg(2+) phenocopies gtl-2(lf) with respect to suppression of clozapine-induced developmental delay and lethality. Our results suggest that GTL-2 TRPM channel function in the excretory canal cell is important for clozapine's developmental effects. TRP channels are expressed in mammalian brain and are implicated in the pathogenesis of mental illnesses but have not been previously implicated in APD action.


Subject(s)
Antipsychotic Agents/pharmacology , Caenorhabditis elegans Proteins/genetics , Clozapine/pharmacology , Gene Expression Regulation, Developmental/drug effects , Phenotype , TRPM Cation Channels/genetics , Animals , Animals, Genetically Modified , Caenorhabditis elegans , Caenorhabditis elegans Proteins/metabolism , Dose-Response Relationship, Drug , Eggs , Gene Expression Regulation, Developmental/genetics , Larva/cytology , Larva/drug effects , Larva/growth & development , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Magnesium/metabolism , Magnesium Sulfate/pharmacology , Mutation/genetics , Neurons/drug effects , Pharyngeal Muscles/drug effects , Pharyngeal Muscles/physiology , RNA Interference/physiology , TRPM Cation Channels/deficiency
18.
Alcohol Clin Exp Res ; 38(5): 1307-14, 2014 May.
Article in English | MEDLINE | ID: mdl-24655029

ABSTRACT

BACKGROUND: Alcoholism is associated with specific brain abnormalities revealed through postmortem studies, including a reduction in glial cell number and dysregulated glutamatergic neurotransmission. Whether these abnormalities contribute to the etiology of alcoholism, are consequences of alcohol use, or both is still unknown. METHODS: We investigated the role of astrocytic glutamate uptake in ethanol (EtOH) binge drinking in mice, using the "drinking in the dark" (DID) paradigm by blocking the astrocytic glutamate transporter (GLT-1) with intracerebroventricular (ICV) administration of dihydrokainic acid (DHK). To determine whether astrocytic glutamate uptake regulates the conditioned rewarding effects of EtOH, we examined the effects of ICV DHK on the acquisition and expression of EtOH-induced conditioned place preference. RESULTS: Blocking central astrocytic glutamate uptake selectively attenuated EtOH binge drinking behavior in mice. DHK did not alter the acquisition or expression of preference for EtOH-associated cues, indicating that reduced astrocytic glutamate trafficking may decrease binge-like drinking without altering the conditioned rewarding effects of EtOH. CONCLUSIONS: Several alternative conclusions are plausible, however, interpreting these data in the context of the human literature, these findings suggest that the reduction of glia in the alcoholic brain may not be a predisposing factor to developing alcoholism and could be a consequence of EtOH toxicity that decreases excessive EtOH intake.


Subject(s)
Alcohol Drinking/physiopathology , Astrocytes/physiology , Ethanol/pharmacology , Glutamic Acid/metabolism , Reward , Amino Acid Transport System X-AG/antagonists & inhibitors , Animals , Astrocytes/drug effects , Glutamic Acid/physiology , Infusions, Intraventricular , Kainic Acid/analogs & derivatives , Kainic Acid/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred DBA
20.
Am J Med Genet B Neuropsychiatr Genet ; 165B(1): 1-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24006268

ABSTRACT

We have recently reported the creation and initial characterization of an etiology-based recombinant mouse model of a severe and inherited form of Major Depressive Disorder (MDD). This was achieved by replacing the corresponding mouse DNA sequence with a 6-base DNA sequence from the human CREB1 promoter that is associated with the development of MDD in men and women from families identified by probands with recurrent, early-onset MDD (RE-MDD). Individuals in these families are also at increased risk for childhood developmental disorders and late life neurodegenerative disorders. The current study used three-dimensional magnetic resonance microscopy (3D-MRM) to determine the effect of the resulting humanized mutation of the mouse Creb1 gene on the anatomy of the mouse brain. Homozygous mutant mice manifested prominent increases in the volume and surface area of the lateral ventricles, as well as reduced volume of the anterior corpus callosum, compared to age/sex-matched wild-type mice. No significant genotype effects were observed on the volume or surface area of total brain, or several brain regions sometimes observed to be abnormal in human depression, including hippocampus, amygdala, or striatum. These findings suggest that at least some forms of MDD result from abnormal brain development produced by inherited genetic variants.


Subject(s)
Corpus Callosum/anatomy & histology , Cyclic AMP Response Element-Binding Protein/genetics , Depressive Disorder, Major/genetics , Lateral Ventricles/anatomy & histology , Promoter Regions, Genetic/genetics , Animals , Corpus Callosum/embryology , Disease Models, Animal , Female , Genetic Predisposition to Disease , Genotype , Humans , Lateral Ventricles/embryology , Magnetic Resonance Imaging , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Sequence Homology , Transfection
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