Part 2:
Genes, the Immune System & Psychiatric Disorders
DNA Methylation and Psychiatric Disorders (2018) Affiliations
Abstract DNA methylation has been an important area of research in the study of molecular mechanism to psychiatric disorders. Recent evidence has suggested that abnormalities in global methylation, methylation of genes, and pathways could play a role in the etiology of many forms of mental illness. In this article, we review the mechanisms of DNA methylation, including the genetic and environmental factors affecting methylation changes. We report and discuss major findings regarding DNA methylation in psychiatric patients, both within the context of global methylation studies and gene-specific methylation studies. Finally, we discuss issues surrounding data quality improvement, the limitations of current methylation analysis methods, and the possibility of using DNA methylation-based treatment for psychiatric disorders in the future. [ The Role of Methylation in Gene Expression | Learn Science ... https://www.nature.com › scitable › topicpage › the-role-o... There are many ways that gene expression is controlled in eukaryotes, but methylation of DNA (not to be confused with histone methylation) is a common epigenetic signaling tool that cells use to lock genes in the "off" position. In recent decades, researchers have learned a great deal about DNA methylation, including how it occurs and where it occurs, and they have also discovered that methylation is an important component in numerous cellular processes, including embryonic development, genomic imprinting, X-chromosome inactivation, and preservation of chromosome stability. Given the many processes in which methylation plays a part, it is perhaps not surprising that researchers have also linked errors in methylation to a variety of devastating consequences, including several human diseases. |
Epigenetics and Addiction (2019) Affiliations
Abstract As an individual becomes addicted to a drug of abuse, nerve cells within the brain's reward circuitry adapt at the epigenetic level during the course of repeated drug exposure. These drug-induced epigenetic adaptations mediate enduring changes in brain function which contribute to life-long, drug-related behavioral abnormalities that define addiction. Targeting these epigenetic alterations will enhance our understanding of the biological basis of addiction and might even yield more effective anti-addiction therapies. However, the complexity of the neuroepigenetic landscape makes it difficult to determine which drug-induced epigenetic changes causally contribute to the pathogenic mechanisms of drug addiction. In this review, we highlight the evidence that epigenetic modifications, specifically histone modifications, within key brain reward regions are correlated with addiction. We then discuss the emerging field of locus-specific neuroepigenetic editing, which is a promising method for determining the causal epigenetic molecular mechanisms that drive an addicted state. Such approaches will substantially increase the field's ability to establish the precise epigenetic mechanisms underlying drug addiction, and could lead to novel treatments for addictive disorders. [Histone Methylation H3K27 methylation has a key role in regulating transcriptional responses from innate immune cells. The histone H3K27me3 demethylase JMJD3, shown to utilize the jumonji (jmj) catalytic domain, showed a rapid induction in response to proinflammatory stimuli. Immune System Disorders and Epigenetics - NCBI - NIHhttps://www.ncbi.nlm.nih.gov › articles › PMC7149935 ] |
Epigenetics and Depression (2019) Affiliation 1Dept of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Munich, Germany. Abstract The risk for major depression is both genetically and environmentally determined. It has been proposed that epigenetic mechanisms could mediate the lasting increases in depression risk following exposure to adverse life events and provide a mechanistic framework within which genetic and environmental factors can be integrated. Epigenetics refers to processes affecting gene expression and translation that do not involve changes in the DNA sequence and include DNA methylation (DNAm) and microRNAs (miRNAs) as well as histone modifications. Here we review evidence for a role of epigenetics in the pathogenesis of depression from studies investigating DNAm, miRNAs, and histone modifications using different tissues and various experimental designs. From these studies, a model emerges where underlying genetic and environmental risk factors, and interactions between the two, could drive aberrant epigenetic mechanisms targeting stress response pathways, neuronal plasticity, and other behaviorally relevant pathways that have been implicated in major depression. . |
Revisiting Inflammation in Bipolar Disorder (2019) Affiliations 1Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, 77054 East Rd., Houston, TX, United States of America. 2School of Sciences, PUCRS, Brazil. 3Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, 77054 East Rd., Houston, TX, United States of America. Abstract Bipolar disorder (BD) has been associated with immune changes, and yet their underlying mechanisms are still not fully understood. Here, we review the current state of the field, concerning the inflammatory alterations observed in the periphery and in the central nervous system, followed by a discussion of potential underlying mechanisms. We focus mainly on recently proposed mechanisms including the role of the gut-brain axis, the release of damage-associated molecular patterns (DAMPs), and the genetic and epigenetic mechanisms. BD [Bipolar Disorder] immunology is an evolving field and current studies indicate this disease is more than a brain disorder, and it can be conceptualized as a multi-system condition. |