Effect of propranolol on differential gene expression in peripheral blood monocytes from mice subject to repeated social defeat

This study tested the effects of repeated social defeat (RSD) on gene expression in peripheral blood monocytes and examined the extent to which these effects were abrogated by the beta-adrenergic antagonist propranolol. Study Type: Risk prediction Gene expression profiling was carried out on peripheral blood monocyte mRNA samples collected from 36 mice randomized to either 6 cycles of repeated social defeat (RSD, n=18) or to parallel home cage control (HCC, n=18) conditions. Within each condition (RSD vs HCC), 9 animals were treated with the beta-adrenergic antagonist propranolol and 9 were treated with an equivalent volume of vehicle. After 6 cycles of RSD or parallel HCC, blood samples were pooled into groups of n=3 samples in each condition, and Illumina Mouse Ref-8 BeadArray assays were performed on RNA from approximately 1 million CD11b+ peripheral blood mononuclear cells (i.e., monocytes) which were immunomagnetically isolated by MACS. The primary research questions are 1) whether expression of pro-inflammatory genes is altered by RSD, and 2) whether treatment with propranolol abrogates these effects.