OCDB: a database collecting genes, miRNAs and drugs for obsessive-compulsive disorder

Genetic and molecular correlates of cortical thickness alterations in adults with obsessive-compulsive disorder: a transcription-neuroimaging association analysis

BACKGROUND

Although numerous neuroimaging studies have depicted neural alterations in individuals with obsessive-compulsive disorder (OCD), a psychiatric disorder characterized by intrusive cognitions and repetitive behaviors, the molecular mechanisms connecting brain structural changes and gene expression remain poorly understood.

METHODS

This study combined the Allen Human Brain Atlas dataset with neuroimaging data from the Meta-Analysis (ENIGMA) consortium and independent cohorts. Later, partial least squares regression and enrichment analysis were performed to probe the correlation between transcription and cortical thickness variation among adults with OCD.

RESULTS

The cortical map of case-control differences in cortical thickness was spatially correlated with cortical expression of a weighted combination of genes enriched for neurobiologically relevant ontology terms preferentially expressed across different cell types and cortical layers. These genes were specifically expressed in brain tissue, spanning all cortical developmental stages. Protein-protein interaction analysis revealed that these genes coded a network of proteins encompassing various highly interactive hubs.

CONCLUSIONS

The study findings bridge the gap between neural structure and transcriptome data in OCD, fostering an integrative understanding of the potential biological mechanisms.

A Cross-Sectional Measurement of Endogenous Oxidative Stress Marker Levels in Obsessive Compulsive Disorder

Background

There is a correlation between the increase in reactive oxygen radicals and the presence of specific mental illnesses. In this context, the objective of this study is to investigate the relationship between obsessive-compulsive disorder and the variations in the levels of several endogenous oxidative stress markers.

Methods

Thirty obsessive-compulsive disorder patients were included in the study as the patient group, and 30 healthy volunteers of matching demographic characteristics were included in the study as the control group. Accordingly, the patient group consisted of 10 females and 20 males with a mean age of 29.5 ± 6.1 years, and the control group consisted of 15 females and 15 males with a mean age of 31.9±5.6 years. The serum nicotinamide adenine dinucleotide phosphate oxidase-2, nicotinamide adenine dinucleotide phosphate oxidase-4, and malondialdehyde levels of the 2 groups were compared using the independent samples t-test. The relationships between the serum nicotinamide adenine dinucleotide phosphate oxidase-2, nicotinamide adenine dinucleotide phosphate oxidase-4, and malondialdehyde levels of the 2 groups were analyzed using the Pearson's correlation coefficient.

Results

The serum nicotinamide adenine dinucleotide phosphate oxidase-2, nicotinamide adenine dinucleotide phosphate oxidase-4, and malondialdehyde levels of the patient group were statistically significantly higher than those of the control group (P < .001). Statistically significant positive correlations were detected between the serum nicotinamide adenine dinucleotide phosphate oxidase-2 and nicotinamide adenine dinucleotide phosphate oxidase-4 levels (r = 0.692, P = .001) and between the serum nicotinamide adenine dinucleotide phosphate oxidase-2 and malondialdehyde levels (r = 0.563, P = .001).

Conclusion

The results of this study indicated that oxidative stress and lipid peroxidation levels were higher in obsessive-compulsive disorder patients. Based on this finding, NOX-2 and NOX-4 levels can be used as indicators of endogenous oxidative stress in obsessive-compulsive disorder patients.

The Evaluation of Thiol/Disulfide Homeostasis and Oxidative DNA Damage in Patients with Obsessive Compulsive Disorder

Objective

In this study, we aimed to examine thiol/disulfide homeostasis and oxidative DNA damage in patients with OCD and compare them with healthy controls.

Methods

Thirty-five patients previously diagnosed with OCD in Van Yuzuncu Yil University Department of Psychiatry and thirty-three healthy volunteers were included in the study. The severity of the symptoms was measured using the Yale-Brown Obsessive-Compulsive Scale. Five μL of blood samples were taken from the patient and control groups. The samples were stored at appropriate conditions until use. Leukocyte DNA was isolated and the levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) and deoxyguanosine were detected to assess the oxidative DNA damage. The level of oxidative DNA damage was expressed as 8-OHdG/10⁶dG. Total thiol/native thiol levels were measured for thiol/disulfide homeostasis. The level of disulfide was determined by subtracting the native thiol value from the total thiol value and the result was divided by two. Results were given as percentages.

Results

The total and native thiol levels in patients with OCD were significantly lower, and the disulfide levels were significantly higher in patients with OCD than healthy control subjects. In addition, 8-OHdG, an indicator of DNA damage, was significantly lower in the control group compared to the patient group.

Conclusion

Increased levels of disulfide/native thiol and disulfide/total thiol in patients with OCD show that levels of oxidative stress were elevated and therefore, higher 8-OHdG levels in patients with OCD is a marker of oxidative DNA damage.

Ancestry-inclusive dog genomics challenges popular breed stereotypes

Behavioral genetics in dogs has focused on modern breeds, which are isolated subgroups with distinctive physical and, purportedly, behavioral characteristics. We interrogated breed stereotypes by surveying owners of 18,385 purebred and mixed-breed dogs and genotyping 2155 dogs. Most behavioral traits are heritable [heritability (h²) > 25%], and admixture patterns in mixed-breed dogs reveal breed propensities. Breed explains just 9% of behavioral variation in individuals. Genome-wide association analyses identify 11 loci that are significantly associated with behavior, and characteristic breed behaviors exhibit genetic complexity. Behavioral loci are not unusually differentiated in breeds, but breed propensities align, albeit weakly, with ancestral function. We propose that behaviors perceived as characteristic of modern breeds derive from thousands of years of polygenic adaptation that predates breed formation, with modern breeds distinguished primarily by aesthetic traits.

MicroRNA Databases and Tools

In this era of big data, sets of methodologies and strategies are designed to extract knowledge from huge volumes of data. However, the cost of where and how to get this information accurately and quickly is extremely important, given the diversity of genomes and the different ways of representing that information. Among the huge set of information and relationships that the genome carries, there are sequences called miRNAs (microRNAs). These sequences were described in the 1990s and are mainly involved in mechanisms of regulation and gene expression. Having this in mind, this chapter focuses on exploring the available literature and providing useful and practical guidance on the miRNA database and tools topic. For that, we organized and present this text in two ways: (a) the update reviews and articles, which best summarize and discuss the theme; and (b) our update investigation on miRNA literature and portals about databases and tools. Finally, we present the main challenge and a possible solution to improve resources and tools.

Polycystic Ovary Syndrome and Risk of Five Common Psychiatric Disorders Among European Women: A Two-Sample Mendelian Randomization Study

Background: Observational studies have implied an association between polycystic ovary syndrome (PCOS) and psychiatric disorders. Here we examined whether PCOS might contribute causally to such disorders, focusing on anxiety disorder (AD), bipolar disorder (BIP), major depression disorder (MDD), obsessive compulsive disorder (OCD), and schizophrenia (SCZ).

Methods: Causality was explored using two-sample Mendelian randomization (MR) with genetic variants as instrumental variables. The genetic variants were from summary data of genome-wide association studies in European populations. First, potential causal effects of PCOS on each psychiatric disorder were evaluated, and then potential reverse causality was also assessed once PCOS was found to be causally associated with any psychiatric disorder. Causal effects were explored using inverse variance weighting, MR-Egger analysis, simulation extrapolation, and weighted median analysis.

Results: Genetically predicted PCOS was positively associated with OCD based on inverse variance weighting (OR 1.339, 95% CI 1.083–1.657, p = 0.007), simulation extrapolation (OR 1.382, 95% CI 1.149–1.662, p = 0.009) and weighted median analysis (OR 1.493, 95% CI 1.145–1.946, p = 0.003). However, genetically predicted OCD was not associated with PCOS. Genetically predicted PCOS did not exert causal effects on AD, BIP, MDD, or SCZ.

Conclusions: In European populations, PCOS may be a causal factor in OCD, but not AD, BIP, MDD, or SCZ.

The association of HTR2A polymorphisms with obsessive-compulsive disorder and its subtypes: A meta-analysis

BACKGROUND

Genetic risk factors that contribute to obsessive-compulsive disorder (OCD) have yet to be elucidated. Historically, serotonergic dysfunction has been implicated. Evidence from the literature points towards the serotonin receptor 2A gene (HTR2A) as a primary candidate. Our meta-analysis investigated whether polymorphisms in HTR2A are associated with OCD or its subtypes, based on sex and age of onset.

METHODS

Studies employing case-control or family-based designs were systematically searched, and those meeting eligibility underwent quality assessment, resulting in 18 studies. A random-effects meta-analysis using standard inverse-variance weighting to compute odds ratio (OR) was conducted. To examine sensitivity, results were also obtained using a more conservative statistical method.

RESULTS

Three HTR2A variants were identified: T102C, G-1438A, and C516T. T102C and G-1438A were analyzed together due to strong linkage disequilibrium, where the 102T allele co-occurs with -1438A allele. Results reported as OR [95%CI] showed that the T/A allele were significantly associated with OCD, 1.14 [1.01, 1.29]. After stratification, results remained significant for females, 1.20 [1.00, 1.45], and early-onset OCD, 1.27 [1.02, 1.58], but not males, 1.06 [0.91, 1.23]. No associations were found for late-onset OCD, 0.98 [0.70, 1.37], or C516T, 1.22 [0.14, 10.37], but conclusions cannot be drawn from two studies.

LIMITATIONS

Associations no longer reached significance with the conservative statistical approach. HTR2A alone cannot explain OCD complexity and limited samples reporting genetic data according to subtypes.

CONCLUSIONS

These results suggest a possible association of HTR2A polymorphisms with OCD, but further investigations considering sex and age of onset with larger samples is needed.

Dysregulated plasma levels of miRNA-132 and miRNA-134 in patients with obsessive-compulsive disorder

Background

Obsessive-compulsive disorder (OCD) is a severe, chronic, disabling neuropsychiatric disorder, the pathophysiology of which has yet to be fully understood. In this study, we aimed to detect the levels of miRNA-132 and miRNA-134 in the plasma of patients with OCD and to analyze the factors influencing OCD.

Methods

The levels of miRNA-132 and miRNA-134 in peripheral blood of 30 patients with OCD and 32 normal controls were detected by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Patients were assessed using clinical scales, including the Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD), and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS).

Results

The plasma levels of miRNA-132 and miRNA 134 in the OCD group were significantly higher than those in the control group (P<0.05). There was no significant correlation between the plasma levels of miR-132 and miR-134 in the OCD group and general demographic (gender, age, and education level) and clinical characteristics (duration of disease, HAMA, HAMD, and Y-BOCS scores).

Conclusions

Patients with OCD have abnormal plasma levels of miRNA-132 and miRNA-134, which may influence the number of dendrites in the cerebral cortex and formation of synapses. Therefore, miRNA-132 and miRNA-134 plasma levels should be considered as potential biomarkers for OCD detection.

How obsessive-compulsive and bipolar disorders meet each other? An integrative gene-based enrichment approach

BACKGROUND

The novel approaches to psychiatric classification assume that disorders, contrary to what was previously thought, are not completely separate phenomena. In this regard, in addition to symptom-based criteria, disturbances are also considered on the basis of lower level components. With this viewpoint, identifying common biochemical markers would be beneficial in adopting a comprehensive strategy for prevention, diagnosis and treatment.

MAIN BODY

One of the problematic areas in clinical settings is the coexistence of both obsessive-compulsive disorder (OCD) and bipolar disorder (BD) that is challenging and difficult to manage. In this study, using a system biologic approach we aimed to assess the interconnectedness of OCD and BD at different levels. Gene Set Enrichment Analysis (GSEA) method was used to identify the shared biological network between the two disorders. The results of the analysis revealed 34 common genes between the two disorders, the most important of which were CACNA1C, GRIA1, DRD2, NOS1, SLC18A1, HTR2A and DRD1. Dopaminergic synapse and cAMP signaling pathway as the pathways, dopamine binding and dopamine neurotransmitter receptor activity as the molecular functions, dendrite and axon part as the cellular component and cortex and striatum as the brain regions were the most significant commonalities.

SHORT CONCLUSION

The results of this study highlight the role of multiple systems, especially the dopaminergic system in linking OCD and BD. The results can be used to estimate the disease course, prognosis, and treatment choice, particularly in the cases of comorbidity. Such perspectives, going beyond symptomatic level, help to identify common endophenotypes between the disorders and provide diagnostic and therapeutic approaches based on biological in addition to the symptomatic level.

ABCD: Alzheimer's disease Biomarkers Comprehensive Database

Alzheimer's disease (AD) is an age-related, non-reversible, and progressive brain disorder. Memory loss, confusion, and personality changes are major symptoms noticed. AD ultimately leads to a severe loss of mental function. Due to lack of effective biomarkers, no effective medication was available for the complete treatment of AD. There is a need to provide all AD-related essential information to the scientific community. Our resource Alzheimer's disease Biomarkers Comprehensive Database (ABCD) is being planned to accomplish this objective. ABCD is a huge collection of AD-related data of molecular markers. The web interface contains information concerning the proteins, genes, transcription factors, SNPs, miRNAs, mitochondrial genes, and expressed genes implicated in AD pathogenesis. In addition to the molecular-level data, the database has information for animal models, medicinal candidates and pathways involved in the AD and some image data for AD patients. ABCD is coupled with some major external resources where the user can retrieve additional general information about the disease. The database was designed in such a manner that user can extract meaningful information about gene, protein, pathway, and regulatory elements based search options. This database is unique in the sense that it is completely dedicated to specific neurological disorder i.e. AD. Further advance options like AD-affected brain image data of patients and structural compound level information add values to our database. Features of this database enable users to extract, analyze and display information related to a disease in many different ways. The database is available for academic purpose and accessible at http://www.bioinfoindia.org/abcd.

Using caffeine on the patients as therapeutic option against treatment-resistant obsessive-compulsive disorder

Introduction

Obsessive-compulsive disorder (OCD) is one of the most common and debilitating diseases. Approximately 40-30% of these patients are resistant to treatment, which auxiliary drugs are used to treat these patients. One of these drugs is caffeine, which is capable of affecting adenosine receptors and interfering with its release and serotonin reuptake. Considering the limitations of previous studies in this area, including lack of control group, this double-blind study compared the effectiveness of caffeine in the management of patients with treatment-resistant OCD in comparison with placebo group.

Materials and Methods

62 patients who referred to the psychiatric clinic of Imam Hossein Hospital in Tehran from 2017 to 2018 were enrolled in the study. According to the psychiatrist's interview, patients with OCD were selected randomly in two groups including caffeine and placebo, after having met the criteria for inclusion and obtaining informed consent. Patients were followed for 8 weeks and compared in terms of the severity of OCD before and after intervention using YBOCS questionnaire.

Results

The two groups of treatment and control were similar in terms of study variables (gender, age, education, age, comorbidity). The mean Yale-Brown Obsessive Compulsive Scale (Y-BOCS) in the treatment and control groups before intervention were determined to be 27.16 and 25.4, respectively, which changed to 24 and 27.23 after medication intervention, which exhibited a decrease of about 3 points (12%) in the treatment group, and was statistically significant based on linear regression analysis (P = 0.009). Considering other variables, the effect of caffeine was still statistically significant in the two groups.

Conclusion

Based on the findings of our study, caffeine can reduce the severity of the symptoms of OCD and serve as an auxiliary treatment for OCD.

Noncoding RNAs Databases: Current Status and Trends

One of the most important resources for researchers of noncoding RNAs is the information available in public databases spread over the internet. However, the effective exploration of this data can represent a daunting task, given the large amount of databases available and the variety of stored data. This chapter describes a classification of databases based on information source, type of RNA, source organisms, data formats, and the mechanisms for information retrieval, detailing the relevance of each of these classifications and its usability by researchers. This classification is used to update a 2012 review, indexing now more than 229 public databases. This review will include an assessment of the new trends for ncRNA research based on the information that is being offered by the databases. Additionally, we will expand the previous analysis focusing on the usability and application of these databases in pathogen and disease research. Finally, this chapter will analyze how currently available database schemas can help the development of new and improved web resources.

MicroRNA-125a-3p is involved in early behavioral disorders in stroke-afflicted rats through the regulation of Cadm2

Ischemic strokes carry a significant risk of mortality and recurrent vascular events. Recent studies suggest that changes in microRNAs (miRNAs or miRs) may affect the development of the stroke. However, few studies have investigated the role of miRNAs in behavioral disorder in early stroke. In the present study, animal models of middle cerebral artery occlusion (MCAO) are used, as well as a cell model of neurite outgrowth to further investigate the role of miRNAs in targeting synapse-associated proteins expression in early stroke. The authors used miRNA expression microarrays on RNA extracted from the cortex tissue samples from the rats of MCAO and control rats. Reverse transcription-quantitative polymerase chain reaction was conducted to verify the candidate miRNAs discovered by microarray analysis. Data indicated that miR-125a was significantly increased in the cortex of the model of MCAO, which were concomitant with that rats of MCAO at the same age displayed significant behavioral deficits. Bioinformatics analysis predicted the cell adhesion molecule 2 (Cadm2, mRNA) neurite outgrowth-associated protein is targeted by miR-125a. Overexpression of miR-125a reduced the level of Cadm2 expression in PC12 cell injury induced by free-serum. In contrast, inhibition of miR-125a using miR-125a inhibitors significantly resulted in higher levels of Cadm2 expression. In conclusion, miR-125a is involved in the behavioral disorder of animal models of MCAO by regulation of Cadm2.

Evaluation of oxidative metabolism and oxidative DNA damage in patients with obsessive-compulsive disorder

AIMS

There are limited published data about the role of oxidative stress in the pathophysiology of obsessive-compulsive disorder (OCD). In addition, oxidative stress and oxidative DNA damage have not been investigated together in OCD. In this study, we aimed to evaluate oxidative stress and oxidative DNA damage in patients with OCD.

METHODS

Forty-two patients with OCD who were diagnosed in the Psychiatry Clinic of Gaziantep University and 38 healthy volunteers were enrolled in the study. Serum 8-hydroxideoxiguanosine (8-OHdG), total antioxidant status, total oxidant status evaluation and oxidative stress index calculation were conducted in Gaziantep University Biochemical Laboratory.

RESULTS

There were no significant differences in the total antioxidant status, total oxidant status and oxidative stress index levels between the patients and control group. However, 8-OHdG levels were significantly higher in OCD patients than controls (P = 0.022). In addition, 8-OHdG levels were significantly lower in patients who took treatment than in patients who were newly diagnosed (P = 0.016).

CONCLUSIONS

In our study, we found that oxidative DNA damage increased in OCD patients even though oxidative stress was normal. In addition, DNA damage was lower in patients who were treated compared to those without treatment.