A report published by Archives of General Psychiatry, one of the JAMA/Archives journals, shows mothers experiencing a psychiatric episode in the first 30 days post-partum appear to have an increased risk of developing bipolar affective disorder. The authors write that : "Childbirth has an important influence on the onset and course of bipolar affective disorder, and studies have shown that episodes of post-partum psychosis are often best considered as presentations of bipolar affective disorder occurring at a time of dramatic psychological and physiological change ... It is also clear, however, that a high number of women with the new onset of a psychiatric disorder in the immediate post-partum period do not receive a diagnosis of bipolar disorder ." Researchers including Trine Munk-Olsen, Ph.
Significant progress has been made in understanding the genetic risk factors underlying psychiatric disease. Recent studies have identified common genetic mutations conferring modest risk and rare variants comprising significant risk. One example of a rare cause of psychiatric disorders is the Disrupted in Schizophrenia-1 (DISC1) gene, first identified in a large Scottish pedigree displaying schizophrenia, bipolar disorder and depression. Common variants in DISC1 have been associated with altered cognition, brain structure and function, but it was unknown how this occurs. A new study co-authored by Li-Huei Tsai, director of MIT's Picower Institute for Learning and Memory, and her colleagues -- Karun K. Singh, Laurel Drane, Yingwei Mao, Zachary Flood and Cillian King -- demonstrates how DISC1 variants impair signaling pathways and disrupt brain development.
Although many mental illnesses are uniquely human, animals sometimes exhibit abnormal behaviors similar to those seen in humans with psychological disorders. Such behaviors are called endophenotypes. Now, researchers at the California Institute of Technology (Caltech) have found that mice lacking a gene that encodes a particular protein found in the synapses of the brain display a number of endophenotypes associated with schizophrenia and autism spectrum disorders. The new findings appear in a recent issue of the Journal of Neuroscience, with Mary Kennedy, the Allen and Lenabelle Davis Professor of Biology at Caltech, as the senior author. The team created mutations in mice so that they were missing the gene for a protein called densin-180, which is abundant in the synapses of the brain, those electro-chemical connections between one neuron and another that enable the formation of networks between the brain's neurons.
Researchers have discovered how the gene variant DISC1, which is linked to schizophrenia and other psychiatric disorders, impairs a particular signalling pathway in neurons that is crucial for normal brain development. Li-Huei Tsai, director of MIT's Picower Institute for Learning and Memory, and colleagues, write about their findings in the 17 November issue of the journal Neuron. DISC1, short for Disrupted in Schizophrenia-1, was first identified in a large Scottish family with high rates of schizophrenia, bipolar disorder and depression, and more recent studies have shown that the mutation can lead to changes in brain structure and impaired cognitive function. But exactly how it did this remained somewhat unclear. For their study, Tsai and colleagues screened the genes of 750 participants.
A new chemical process developed by a team of Harvard researchers greatly increases the utility of Positron Emission Tomography (PET) in creating real-time 3-D images of chemical process occurring inside the human body. This new work by Tobias Ritter, Associate Professor of Chemistry and Chemical Biology, and colleagues holds out the tantalizing possibility of using PET scans to peer into any number of functions inside the bodies of living patients by simplifying the process of creating "tracer" molecules used to create the 3-D images. For example, imagine a pharmaceutical company developing new treatments by studying the way "micro-doses" of drugs behave in the bodies of living humans. Imagine researchers using non-invasive tests to study the efficacy of drugs aimed at combatting disorders such as Alzheimer's disease, and identify the physiological differences in the brains of patients suffering from schizophrenia and bipolar disorder.