Fig. 2: Chronic exposure to S100B has pronounced effects on developing synapses.
a, b Primary hippocampal neurons were treated with either 30 μM S100Bwt or S100Bmut from DIV6, DIV8 or DIV10 until DIV11. a Treatment at early developmental stages (DIV6, DIV8) in combination with a prolonged exposure to S100Bwt but not S100Bmut led to a significant reduction in immunofluorescence intensities of SHANK2 immunoreactive puncta (n = 8–10 cells, Welch’s ANOVA, F = 12.518, p < 0.001; post-hoc analyses: control vs. wtDIV6, p < 0.05; control vs. wtDIV8, p < 0.05; control vs. mutDIV6, p > 0.05; wtDIV6 vs. mutDIV6, p < 0.05; wtDIV6 vs. wtDIV10, p < 0.05). b Decreased fluorescence intensity of SHANK3 immunoreactive puncta was seen in hippocampal neurons treated with S100Bwt protein from DIV6 or DIV8 on compared to untreated control (DIV6) or S100Bmut treated cells (DIV8) respectively. Non-zinc-binding S100Bmut protein did not affect SHANK3 fluorescence intensity independent of time-point of administration (n = 8–10 cells, one way ANOVA, F(6,61)= 7.7018, p < 0.001; post-hoc analyses: control vs. wtDIV6 p = 0.00111; wtDIV6 vs. mutDIV6, p = 0.0952; wtDIV8 vs. mutDIV8, p = 0.0227; control vs. mutDIV6, p = 0.6094). c Exemplary images of synapses of control neurons and neurons treated on DIV6 with S100Bwt or S100Bmut.
