130 research outputs found
Inhibition of CREB Activity in the Dorsal Portion of the Striatum Potentiates Behavioral Responses to Drugs of Abuse
The striatum participates in multiple forms of behavioral adaptation, including habit formation, other forms of procedural memory, and short- and long-term responses to drugs of abuse. The cyclic-AMP response element binding protein (CREB) family of transcription factors has been implicated in various forms of behavioral plasticity, but its role in the dorsal portion of the striatum-has been little explored. We previously showed that in transgenic mice in which CREB function is inhibited in the dorsal striatum, bidirectional synaptic plasticity and certain forms of long-term procedural memory are impaired. Here we show, in startling contrast, that inhibition of striatal CREB facilitates cocaine- and morphine-place conditioning and enhances locomotor sensitization to cocaine. These findings propose CREB as a positive regulator of dorsal striatum-dependent procedural learning but a negative regulator of drug-related learning
Characterization of a mutant strain of \u3ci\u3eSaccharomyces cerevisiae\u3c/i\u3e with a deletion of the RAD27 gene, a structural homolog of the RAD2 nucleotide excision repair gene
We have constructed a strain of Saccharomyces cerevisiae with a deletion of the YKL510 open reading frame, which was initially identified in chromosome XI as a homolog of the RAD2 nucleotide excision repair gene (A. Jacquier, P. Legrain, and B. Dujon, Yeast 8:121â132, 1992). The mutant strain exhibits increased sensitivity to UV light and to the alkylating agent methylmethane sulfonate but not to ionizing radiation. We have renamed the YKL510 open reading frame the RAD27 gene, in keeping with the accepted nomenclature for radiationsensitive yeast mutants. Epistasis analysis indicates that the gene is in the RAD6 group of genes, which are involved in DNA damage tolerance. The mutant strain also exhibits increased plasmid loss, increased spontaneous mutagenesis, and a temperature-sensitive lethality whose phenotype suggests a defect in DNA replication. Levels of the RAD27 gene transcript are cell cycle regulated in a manner similar to those for several other genes whose products are known to be involved in DNA replication. We discuss the possible role of Rad27 protein in DNA repair and replication
The Role of Stress in the Pathogenesis and Maintenance of Obsessive-Compulsive Disorder
Individuals with obsessive-compulsive disorder often identify psychosocial stress as a factor that exacerbates their symptoms, and many trace the onset of symptoms to a stressful period of life or a discrete traumatic incident. However, the pathophysiological relationship between stress and obsessive-compulsive disorder remains poorly characterized: it is unclear whether trauma or stress is an independent cause of obsessive-compulsive disorder symptoms, a triggering factor that interacts with a preexisting diathesis, or simply a nonspecific factor that can exacerbate obsessive-compulsive disorder along with other aspects of psychiatric symptomatology. Nonetheless, preclinical research has demonstrated that stress has conspicuous effects on corticostriatal and limbic circuitry. Specifically, stress can lead to neuronal atrophy in frontal cortices (particularly the medial prefrontal cortex), the dorsomedial striatum (caudate), and the hippocampus. Stress can also result in neuronal hypertrophy in the dorsolateral striatum (putamen) and amygdala. These neurobiological effects mirror reported neural abnormalities in obsessive-compulsive disorder and may contribute to an imbalance between goal-directed and habitual behavior, an imbalance that is implicated in the pathogenesis and expression of obsessive-compulsive disorder symptomatology. The modulation of corticostriatal and limbic circuits by stress and the resultant imbalance between habit and goal-directed learning and behavior offers a framework for investigating how stress may exacerbate or trigger obsessive-compulsive disorder symptomatology
Corrigendum: Safety, feasibility, tolerability, and clinical effects of repeated psilocybin dosing combined with non-directive support in the treatment of obsessive-compulsive disorder: protocol for a randomized, waitlist-controlled trial with blinded ratings
Safety, feasibility, tolerability, and clinical effects of repeated psilocybin dosing combined with non-directive support in the treatment of obsessive-compulsive disorder: protocol for a randomized, waitlist-controlled trial with blinded ratings
BackgroundTo date, few randomized controlled trials of psilocybin with non-directive support exist for obsessive-compulsive disorder (OCD). Results and participant feedback from an interim analysis of an ongoing single-dose trial (NCT03356483) converged on the possibility of administering a higher fixed dose and/or more doses of psilocybin in future trials for presumably greater benefits.ObjectivesThis trial aims to evaluate the safety, feasibility, tolerability, and clinical effects of two doses of psilocybin paired with non-directive support in the treatment of OCD. This trial also seeks to examine whether two doses of psilocybin lead to greater OCD symptom reduction than a single dose, and to elucidate psychological mechanisms underlying the effects of psilocybin on OCD.DesignA randomized (1:1), waitlist-controlled design with blinded ratings will be used to examine the effects of two doses of oral psilocybin paired with non-directive support vs. waitlist control on OCD symptoms. An adaptive dose selection strategy will be implemented (i.e., first dose: 25âmg; second dose: 25 or 30âmg).Methods and analysisThis single-site trial will enroll 30 adult participants with treatment-refractory OCD. Aside from safety, feasibility, and tolerability metrics, primary outcomes include OCD symptoms assessed on the Yale-Brown Obsessive-Compulsive Scale â Second Edition (Y-BOCS-II). A blinded independent rater will assess primary outcomes at baseline and the primary endpoint at the end of the second dosing week. Participants will be followed up to 12âmonths post-second dosing. Participants randomized to waitlist will be rescreened after 7âweeks post-randomization, and begin their delayed treatment phase thereafter if still eligible.EthicsWritten informed consent will be obtained from participants. The institutional review board has approved this trial (protocol v. 1.7; HIC #2000032623).DiscussionThis study seeks to advance our ability to treat refractory OCD, and catalyze future research seeking to optimize the process of psilocybin treatment for OCD through understanding relevant psychological mechanisms.Clinical trial registration: ClinicalTrials.gov, identifier NCT05370911
White matter abnormalities in the Hdc knockout mouse, a model of tic and OCD pathophysiology
INTRODUCTION: An inactivating mutation in the
MATERIALS AND METHODS: We performed exploratory RNA-seq to identify pathological alterations in several brain regions in
RESULTS: Exploratory RNA-Seq analysis revealed, unexpectedly, that genes associated with oligodendrocytes and with myelin production are upregulated in the dorsal striatum of these mice. This was confirmed by qPCR, immunostaining, and immunoblotting. These results suggest an abnormality in myelination in the striatum. To test this in an intact mouse brain, we performed whole-brain
DISCUSSION: While the DTI literature in individuals with TS is sparse, these results are consistent with findings of disrupted descending cortical projections in patients with tics. Th
Internationale Beziehungen und Soziologie : das âScharnierâ der Differenzierung
Meta-analysis of the heterogeneous symptoms of obsessive-compulsive disorder (OCD) has found a four-factor structure of symptom dimensions consisting of cleaning, forbidden thoughts, symmetry, and hoarding. Research into age of onset of symptom dimensions has yielded inconsistent results, and it is unknown whether symptoms along these dimensions differ in their clinical course. We assessed age of onset and clinical course of different OCD symptom dimensions in a large cohort of adult patients. Nine-hundred fifty-five subjects were assessed using the Dimensional Yale-Brown Obsessive-Compulsive Scale. For age of onset analysis, we tested across three methods of classification: (1) primary (more severe) symptom dimension (2) clinically significant symptoms within a dimension or (3) any symptoms within a dimension. Age of onset was defined as the earliest age of onset reported for any individual item within a symptom dimension. For analysis of different types of clinical course, we used chi-square tests to assess for differences between primary symptom dimensions. OCD symptoms in the symmetry dimension had an earlier age of onset than other OCD symptom dimensions. These findings remained significant across all three methods of classification and controlling for gender and comorbid tics. No significant differences were found between the other dimensions. Subjects with primary OCD symptoms in the forbidden thoughts dimension were more likely to report a waxing-and-waning course, whereas symmetry symptoms were less likely to be associated with a waxing-and-waning course. © 2013
Impaired bidirectional synaptic plasticity and procedural memory formation in striatum-specific cAMP response element-binding protein-deficient mice
The striatum has a well documented role in procedural learning and memory. However, the synaptic and molecular mechanisms of acquisition and storage of this form of memory remain poorly understood. We examined procedural memory and plasticity in transgenic mice reversibly expressing a dominant-negative cAMP response element-binding protein (CREB) mutant in the dorsal striatum. In these transgenic mice, corticostriatal long-term potentiation and depression are abolished, indicating that CREB function is essential for bidirectional long-term synaptic plasticity in this structure. Importantly, CREB-deficient animals show reversible alterations in several forms of striatum-dependent memory, including footshock avoidance learning and "response" learning in the cross maze. These findings implicate transcriptional regulation by CREB family transcription factors in striatum-dependent information processing and provide the first clear correlation between procedural learning and memory and synaptic plasticity at the corticostriatal synapse
Association of polymorphisms in HCN4 with mood disorders and obsessive compulsive disorder
Hyperpolarization activated cyclic nucleotide-gated (HCN) potassium channels are implicated in the control of neuronal excitability and are expressed widely in the brain. HCN4 is expressed in brain regions relevant to mood and anxiety disorders including specific thalamic nuclei, the basolateral amygdala, and the midbrain dopamine system. We therefore examined the association of HCN4 with a group of mood and anxiety disorders. We genotyped nine tag SNPs in the HCN4 gene using Sequenom iPLEX Gold technology in 285 Caucasian patients with DSM-IV mood disorders and/or obsessive compulsive disorder and 384 Caucasian controls. HCN4 polymorphisms were analyzed using single marker and haplotype-based association methods. Three SNPs showed nominal association in our population (rs12905211, rs3859014, rs498005). SNP rs12905211 maintained significance after Bonferroni correction, with allele T and haplotype CTC overrepresented in cases. These findings suggest HCN4 as a genetic susceptibility factor for mood and anxiety disorders; however, these results will require replication using a larger sample
The role of leukocyte-stromal interactions in chronic inflammatory joint disease
Rheumatoid arthritis (RA) is a debilitating, chronic, persistent inflammatory disease that is characterised by painful and swollen joints. The aetiology of RA is unknown, however whereas past research has concentrated on the role of immune or inflammatory infiltrating cells in inflammation, it is becoming clear that stromal cells play a critical part in regulating the quality and duration of an inflammatory response. In this review we assess the role of fibroblasts within the inflamed synovium in modulating immune responses; in particular we examine the role of stromal cells in the switch from resolving to persistent inflammation as is found in the rheumatoid synovium
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