Fig. 4

miR-146a overexpression alter neuronal and glial cells biology. a Efficacy of viral induction 24 h post-infection with lentivirus carrying the empty vector (control) or miR-146a. Top panel shows primary mouse astrocyte expressing GFP; DAPI was used to counterstain the nucleus. Bottom left panel shows miR-146a level (±SD) induced by the virus; expression was measured by Taqman assay and normalized against miR-221 in technical triplicates; bottom right panel shows the expression of Nlng1 and Traf6 (±SD) measured by RT-qPCR in technical triplicates, normalized against Actb; **P < 0.01, ***P value <0.001 by Student’s paired two-tailed t test. b Growth of primary astrocyte is significantly impaired by miR-146a upregulation (red line) compared to the control (green line). Cell growth, displayed as normalized cell index (±SD), was continuously monitored using the Xcelligence system over 4 days. Statistic analysis was performed using data collected from technical quadruplicates at 72 h post-infection. The graph is from one repeat of three showing the same results. ***P value <0.001 by Student’s paired two-tailed t test. c Glutamate uptake is significantly increased in astrocytes overexpressing miR-146a. Following a published protocol [53], uptake of radioactive glutamate (±SD) was counted as count per minute (CPM), normalized against total protein and CPM values of samples treated with the glutamate transporter blocker PDC. The graph is from one repeat of three showing the same results. *P value <0.05 by Student’s paired two-tailed t test. d miR-146a upregulation inhibits neurite outgrowth. Sholl analysis of dendritic arborisation of control and miR-146a-overexpressing neurons. *P < 0.05; **P < 0.01. To test for differences in intersections between blank and miR-146a neurons, each distance (10 μm steps) was tested by one-way ANOVA statistical test followed by the Holm-Sidak post hoc test. When data where not following a normal distribution, we used the one-way ANOVA on ranks and Dunn’s method for post hoc test