Fig. 9

Systemic effects: Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) does not modify splenic and serum levels of pro-inflammatory and anti-inflammatory markers in DNBS colitic and non-colitic mice. taVNS (with stimulation parameters of 10 volts, a 500 µs pulse width, 30 s on/off duration, 10 min stimulation duration, and a frequency of 20 Hz) and no stimulation (anesthesia without any stimulation) were performed for the taVNS and CTRL (no stimulation) groups, respectively, beginning one day before the induction of acute colitis and continued daily until the mice were sacrificed. After 24 h, acute colitis was induced in the colitis (dinitrobenzene sulfonic acid (DNBS)) groups by a single intrarectal dose (100 µL) of 4 mg/mouse DNBS dissolved in 30% ethanol (ETOH) at time point 0, with the ETOH groups receiving 30% ethanol. Splenic protein levels of interleukin (IL)−1β (A), TGF-β (B), and IL-10 (C) and serum levels of TGF-β (D). One-way ANOVA and multiple parametric comparison tests (Bonferroni and Šídák) were used to calculate P values. The significance level was set at p < 0.05. n = 5–8 mice/group. Each value is presented as the mean ± SD. This experiment was repeated at least four times