MicroRNA Correlates of Childhood Maltreatment and Suicidality

This is a research study to find out if childhood trauma and stress are associated with depression or suicidal risk. The study will assess the effects of both short-term and long-term stress on biomarker (e.g. miRNA \[MiRNA\]) levels. miRNAs are a type of RNA (genetic material that is translated into protein) that are found in throughout the body and blood. They are called microRNA because their size is much smaller than typical RNA molecules. miRNAs are highly responsive to environment. This responsiveness is reflected in their expression in individuals who are affected by environment such as stress. The investigators are gathering genetic material, including DNA and RNA, from each participant. The RNA will be taken from the small vesicles and cells in the participant's blood and analyzed. The vesicles are small objects that occur normally in the blood and that contain RNA. This information may help us to understand the cause of mental illness and to improve medical and psychiatric care in the future. There will be 450 participants enrolled in this study.

The purpose of the study is to determine if the relationship between a history of childhood maltreatment (CM) and suicide risk is associated with alterations in the expression and epigenetic modification of specific microRNAs (miRNAs), thereby providing a molecular signature of suicide risk in people with CM. miRNAs are short regulatory RNAs that transduce environmental events into changes in protein synthesis in cells. The environment can induce permanent changes in miRNA expression. Aim 1 is to identify a set of neural-derived exosomal miRNAs that are associated with the interaction of suicidality and CM. Aim 2 is to examine whether an acute experimental stressor, the Trier Social Stress Test (TSST), impacts the expression of these miRNAs in suicidal patients with and without CM. Aim 3 will examine potential mechanisms by which altered miRNAs may contribute to CM-associated suicidal behavior. Aim 4 will examine if changes in CM-associated miRNAs are explained by modifications in their DNA methylation.