American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics: The Official Publication of the International Society of Psychiatric Genetics
Stress is a major contributor to anxiety and mood disorders. The recent discovery of epigenetic changes in the brain resulting from stress has enhanced our understanding of the mechanism by which stress is able to promote these disorders. Although epigenetics encompasses chemical modifications that occur at both DNA and histones, much attention has been focused on stress-induced DNA methylation changes on behavior.
Huntington's disease (HD) is a lethal, autosomal dominant neurodegenerative disorder caused by CAG repeat expansions at exon 1 of the huntingtin (Htt) gene, which encodes for a mutant huntingtin protein (mHtt). Prominent symptoms of HD include motor dysfunction, characterized by chorea; psychiatric disturbances such as mood and personality changes; and cognitive decline that may lead to dementia.
Clinical studies find that childhood adversity and stressful life events in adulthood increase the risk for major depression and for suicide. The predispositions to either major depression or suicide are thought to depend on genetic risk factors or epigenetic effects. We investigated DNA methylation signatures postmortem in brains of suicides with diagnosis of major depressive disorder. DNA methylation levels were determined at single C-phosphate-G (CpG) resolution sites within ventral prefrontal cortex of 53 suicides and nonpsychiatric controls, aged 16 to 89 years.
East Asian Archives of Psychiatry: Official Journal of the Hong Kong College of Psychiatrists = Dong Ya Jing Shen Ke Xue Zhi: Xianggang Jing Shen Ke Yi Xue Yuan Qi Kan
Anticipation is a phenomenon in which successive generations within a family experience an earlier age of onset and a more severe form of a given illness. It has been observed in various neurological and psychiatric conditions, including bipolar disorder. The molecular basis of anticipation involves trinucleotide repeat expansions in genes, but this has not been conclusively demonstrated in bipolar disorder. The histories of 3 father-son pairs are presented.
Epigenetics is the study of chromatin-the physical material that forms chromosomes, composed of DNA wound around specialized histone proteins-and of how the modification of chromatin acts to establish stable states of gene expression in a cell-specific manner. Chromatin is regulated through three mechanisms: DNA methylation, histone modification, and RNA interference. These basic biological processes form the molecular interface between the genome and the environment, contributing to the regulation of gene expression in health and disease.
Some of the latest advances in personalized psychiatry with future research directions are discussed in this article. Many factors contribute to the phenotypic psychiatric profile in individual patients. These overlapping factors include but are not limited to genetics, epigenetics, central nervous system circuit alterations, family history, past personal history, environmental influences including early life stress, and more recent life stressors. The authors discuss the role of pharmacogenomics, particularly in the cytochrome P450 enzyme system in relation to treatment response.
The neurophysiological link between neuropathic pain and depression remains unknown despite evident high comorbidity of these two disorders. However, there is convincing evidence that genotype plays a role in both pain and depression. Using various types of genetic analysis - population genetics, cytogenetics and molecular technologies - specific genes have been implicated in mediating almost all aspects of nociception and mood disorders. The current review attempts to identify specific genes and epigenetic mechanisms common to both disorders.
Astrocytes orchestrate arrangement and functions of neuronal circuits and of the blood-brain barrier. Dysfunctional astrocytes characterize mood disorders, here showcased by deregulation of the astrocyte end-feet protein Aquaporin-4 around blood vessels and, hypothetically, of the astrocyte-specific phagocytic protein MEGF10 to shape synapses. Development of mood disorders is often a result of 'gene ◊ environment' interactions, regulated among others by histone modifications and related modulator enzymes, which rapidly promote adaptive responses.
The Journal of Pain: Official Journal of the American Pain Society
The clinical pattern of neuropathic pain, diagnosed using the quantitative sensory testing (QST) battery (German Research Network on Neuropathic Pain), could be partly mimicked in healthy volunteers after topical capsaicin application. However, similar to clinical neuropathic pain that develops in only a subgroup of patients who have a neurologic lesion, this attempt to mimick a neuropathic pain pattern succeeded only in a small fraction (18%) of healthy individuals.
Advances in Clinical and Experimental Medicine: Official Organ Wroclaw Medical University
BACKGROUND: Psychological factors are one of many that contribute to the increased risk of a psychiatric disorder's occurrence after childbirth. OBJECTIVES: The aim of this work was to determine the relation between psychological variables, such as sense of self-efficacy and dispositional optimism, and the risk of mood disorder's occurrence in women after childbirth. MATERIAL AND METHODS: Two hundred eighty five women, who gave birth in the University Hospital no. 2 in Bydgoszcz, took part in the study.