Galanin expression before (CTRL) and after copper sulfate treatment (CuSO4). Galanin is approximately 4 times upregulated after copper sulfate exposure compared to the untreated group. Data and mean ± SEM were pulled from three independent experiments. **** p < 0.0001 (determined using unpaired t test).

Cell degeneration after copper sulfate treatment. Number of fluorescent pixels after copper sulfate exposure in the wild-type galn+/+ group (galn+/+), a line with galanin knockout galn−/− (galn−/−) and wild-type galn+/+ treated with galanin analog NAX 5055 (NAX) and a line with galanin overexpression Tg(hsp70l:galn) (galn-HS). Data and mean ± SEM were pulled from three independent experiments. ** p < 0.01; *** p < 0.001 (determined using ANOVA with Tukey’s post hoc test).

Quantitative PCR of irg1l, il1b and tnfa after copper sulfate incubation. (A–C) qPCR of irg1l, il1b and tnfa after incubation with copper sulfate in galn+/+, galn−/− and wild-type galn+/+ treated with galanin analog NAX 5055 (NAX) and a line with galanin overexpression Tg(hsp70l:galn) (galn-HS) groups was performed at 3 dpf. Control wild-type galn+/+ larvae (galn+/+ ctrl) were incubated only in PBS without copper sulfate. Data and mean ± SEM were pulled from three independent experiments. * p < 0.05; ** p < 0.01; *** p < 0.001; **** p < 0.0001 (determined using ANOVA with Tukey’s post hoc test); ns, not significant.