Women who abuse alcohol are twice as likely to develop anxiety disorders compared with men, a phenomenon in which the underlying biological mechanisms are unknown. Our overall objective is to identify the interactive effects of alcohol and estrogen on arginine vasopressin (AVP), a well-established key molecular mediator of anxiety, in order to elucidate the molecular mechanisms predisposing women to increased risk of anxiety disorders. Adolescent binge drinking is a potential risk factor for the development of adult anxiety disorders due to the heightened stress reactivity that occurs as a direct result of increased circulating estrogens during pubertal development. Little is known about the long-term neurobiological consequences of alcohol consumption during puberty, which is a dynamic and important period of brain development that involves changes in cortical gray matter, synaptic connectivity, and increased neurogenesis. Exposure of alcohol during this critical period of extensive brain remodeling may result in permanent neuronal damage or disruptions in the formation of new neuronal connections, which might manifest as adult behavioral psychoses, including anxiety disorder. Our preliminary data show that 1) alcohol exposure during puberty increased AVP gene expression in specific regions of the brain. Therefore, the experiments proposed in Specific Aim 1 will directly test the hypotheses that there is a critical window of time during pubertal development when the AVP system is most vulnerable to the effects of alcohol and (2) that estrogen exacerbates the effects of alcohol on AVP gene expression. Also, our preliminary data demonstrate that alcohol treatment and estrogen receptor ligands increased AVP gene expression in neuronal cells derived from the hypothalamus, and gene expression is closely correlated with the activity of the gene promoter. Alcohol also activates estrogen-signaling pathways in the brain, which suggests that the underlying mechanisms for alcohol-induced changes in AVP may be mediated by estrogen signaling pathways. Therefore, the experiments proposed in Specific Aim 2 will directly test the hypotheses that (1) acute alcohol exposure increases AVP promoter activity in neuronal cells, (2) that there are specific regulatory regions of the AVP promoter that interact with alcohol, and (3) that estrogen and alcohol interact synergistically to increase AVP promoter activity. To date, specific molecular and neuroendocrine markers that are activated by alcohol during puberty have not been identified. This proposal is focused on a specific candidate gene (AVP) and its downstream signaling pathways that are developmentally shaped during puberty. We expect these studies to show that AVP is permanently altered, either as a direct target for alcohol or indirectly through steroid hormone receptor signaling pathways. Thus, the value of this research lies in the potential for therapeutic approaches that would target specific genes and perhaps reverse brain damage caused by alcohol consumption during pubertal development as well as strengthen reasons for abstaining from alcohol during that time.
Women who abuse alcohol are twice as likely to develop anxiety disorders compared with men, a phenomenon in which the underlying biological mechanisms are unknown. This proposal is focused on a specific candidate gene (AVP) and its downstream signaling pathways that are developmentally shaped during puberty. We expect these studies to show that AVP is permanently altered, either as a direct target for alcohol or indirectly through steroid hormone receptor signaling pathways. Thus, the value of this research lies in the potential for therapeutic approaches that would target specific genes and perhaps reverse brain damage caused by alcohol consumption during pubertal development as well as strengthen reasons for abstaining from alcohol during that time.
