An exploratory microarray analysis of estrogen-mediated gene expression in central pathways that control energy balance in female rats (Rattus norvegicus)

OBJECTIVE: Obesity and associated conditions are concerning, especially during menopause. Estrogens influence energy balance in key brain regions including the arcuate nucleus (ARC), paraventricular nucleus (PVN), and the nucleus of the solitary tract (NTS). The mechanisms by which estrogens influence energy balance are incompletely understood. Accordingly, we used a microarray analysis to investigate estradiol benzoate (EB)-regulated gene expression within the ARC, PVN, and NTS of ovariectomized rats treated with EB or Oil vehicle. DAVID Bioinformatics was used to identify enriched biological themes. RESULTS: Within the ARC, EB did not alter gene expression of neuropeptides or receptors known to influence energy balance. In the PVN, EB treatment increased Npy1r and Avp expression, with notable effect sizes in the expression of Oxt, Crh, Trh, and Mc3r. Gene expression in the NTS was minimally affected by EB. Within the PVN, DAVID Bioinformatics revealed enrichment in pathways related to cell signaling. Although variability was high due to small sample size and technical challenges inherent to microdissection, this exploratory study provides preliminary gene expression profiles of EB-regulation within the ARC, PVN, and NTS. These findings may serve as a basis for future, targeted investigations of EB regulation within intracellular signaling pathways.