The Effects of Enriched Environment on Paraventricular Hypothalamic Brain-derived Neurotrophic Factor Expression

The regulation of energy homeostasis involves a balance between food intake and energy expenditure. The hypothalamus is a crucial regulator for energy balance and consists of several discrete nuclei, including the arcuate (ARC), ventromedial (VMH), dorsomedial (DMH), and paraventricular (PVH) hypothalamus. Brain-derived neurotrophic factor (BDNF) expressed in hypothalamic nuclei is significant in regulating energy homeostasis. Our studies demonstrated that an enriched environment (EE), a complex housing with social and physical stimulation, upregulated BDNF expression in the ARC and VMH/DMH leading to an anti-obesity and anti-tumor phenotype. Moreover, the EE anti-obesity phenotype can be mimicked by overexpression of ARC and VMH/DMH Bdnf. While studies have shown diet- and genetic- induced obesity can be reversed by transferring the Bdnf gene to ARC and VMH/DMH, the roles of other nuclei in mediating the EE phenotype is not known. Research has shown that PVH BDNF has a strong and lasting impact on suppressing food intake and increasing energy expenditure, and the deletion of Bdnf in the PVH leads to hyperphagia and severe obesity. Thus, we hypothesized PVH Bdnf is upregulated by EE. Our results did not demonstrate significant upregulation of Bdnf expression in PVH or ARC after EE exposure. However, we observed a markedly increase of Vgf (non-acronymic) expression in PVH of EE mice, suggesting Vgf can be our next target gene of interest to study EE’s anti-obesity effects.No embargoAcademic Major: Neuroscienc