Fig. 2: LCN2 acts in mPFC to direct anxiety-like behaviors.
From: Stress increases hepatic release of lipocalin 2 which contributes to anxiety-like behavior in mice
a Intravenous injection of recombinant LCN2-Alxa Fluor 488 resulted in specific protein binding onto cells expressing SLC22A17 in prelimbic (PrL) region. Triplicated studies were performed. Scale bar, 200 μm on left, and 100 μm on right. b Schematic diagrams of LCN2 over-expression in mPFC. Mice received an AAV vector expressing Lcn2 gene. c Left panel, viral transfection site within prelimbic (PrL) region of mPFC. Right, LCN2 protein expression. Scale bar, 200 μm on left, and 100 μm on right. d Viral infection remarkably enhanced local gene expression of Lcn2. Two-sided unpaired t-test, t(8) = 8.953, P < 0.0001. N = 5 mice in each group. e As similar with CRS treatment, Lcn2 gene over-expression in mPFC resulted in lower time duration in the open field. One-way ANOVA, F(2,18) = 38.69, P < 0.0001. f Anxiety-like phenotypes were identified as lower time spent on the open arm in both AAV-LCN2 and CRS groups. One-way ANOVA, F(2,18) = 121.0, P < 0.0001. g Avoidance toward the light box were observed with LCN2 transfection. One-way ANOVA, F(2,18) = 11.19, P = 0.0007. N = 7 mice in each group in (e–g). h Experimental outlines for LCN2 blocking assay, in which Ab-LCN2 was directly applied on mouse mPFC with over-expression of Lcn2 gene. i Fluorescent image showed the infection of AAV-LCN2. Triplicated studies were performed. Scale bar, 200 μm. j Ab-LCN2 remarkably decreased LCN2 protein contents in mPFC. One-way ANOVA, F(3,16) = 87.50, P < 0.0001. N = 5 mice in each group. k Ab-LCN2 infusion prevented the behavioral deficits induced by mPFC-specific LCN2 over-expression. One-way ANOVA, F(3,24) = 9.571, P = 0.0002. l The abnormal behavior in the elevated plus-maze induced by AAV-LCN2 was rescued after Ab-LCN2 administration. One-way ANOVA, F(3,24) = 17.60, P < 0.0001. m The light-avoidance deficit was also prevented under LCN2 neutralization. One-way ANOVA, F(3,24) = 18.88, P < 0.0001. N = 7 mice in each group in (k–m). Exact P-values were indicated using Tukey’s post-hoc comparison in (e–m). All data were presented as mean ± sem. Source data are provided as a Source Data file.
