Fig. 1

BoNT/A facial injection relieves depressive-like behaviors of CRS-induced depression mice. a Schematic of grouping and experimental design. b, c CRS mice performed depressive-like behaviors in the FST and SPT compared to the naïve mice, and 30 U/kg of BoNT/A facial pre-injection reverses the despair-, b and anhedonia-phenotypes, c of saline-administered CRS mice in the group of pre-injection 6 weeks prior to the restraint end. n = 10 animals from the subgroup of Naïve + Saline, and n = 13 animals from the other four subgroups, respectively. One-way ANOVA followed by Dunnett’s multiple comparisons test comparing each subgroup with the subgroup of CRS mice injected with saline, F _{(4, 57)} = 4.603, P = 0.0027 and F _{(4, 57)} = 4.65, P = 0.0026 in b; F _{(4, 57)} = 4.13, P = 0.0052 in c. The P-value of Dunnett’s multiple comparisons: Naïve + Saline vs. CRS + Saline: P = 0.0057, CRS + Saline vs. CRS + 3 U/kg: P = 0.7601, CRS + Saline vs. CRS + 10 U/kg: P = 0.3935, CRS + Saline vs. CRS + 30 U/kg: P = 0.004 of latency of immobility in b; Naïve + Saline vs. CRS + Saline: P = 0.0089, CRS + Saline vs. CRS + 3 U/kg: P = 0.2691, CRS + Saline vs. CRS + 10 U/kg: P = 0.0872, CRS + Saline vs. CRS + 30 U/kg: P = 0.0008 of total time of immobility in b; Naïve + Saline vs. CRS + Saline: P = 0.01, CRS + Saline vs. CRS + 3 U/kg: P = 0.9247, CRS + Saline vs. CRS + 10 U/kg: P = 0.9976, CRS + Saline vs. CRS + 30 U/kg: P = 0.0381 of sucrose preference in c. d, e CRS mice in the subgroups of facial pre-injection of three different dosages of BoNT/A performed relieved depressive-like behaviors depicted by improved despair and anhedonia in the group of BoNT/A pre-injection 3 weeks prior to the restraint end. n = 12 animals from the subgroup of Naïve + Saline, and n = 15 animals from the other four subgroups, respectively. One-way ANOVA followed by Dunnett’s multiple comparisons test comparing each subgroup with the subgroup of CRS mice injected with saline, F _{(4, 67)} = 3.364, P = 0.0144 and F _{(4, 57)} = 11, P < 0.0001 in d; F _{(4, 57)} = 5.241, P = 0.0010 in e. The P-value of Dunnett’s multiple comparisons: Naïve + Saline vs. CRS + Saline: P = 0.0004, CRS + Saline vs. CRS + 3 U/kg: P = 0.0307, CRS + Saline vs. CRS + 10 U/kg: P = 0.0023, CRS + Saline vs. CRS + 30 U/kg: P = 0.0017 of latency of immobility in d; Naïve + Saline vs. CRS + Saline: P = 0.0001, CRS + Saline vs. CRS + 3 U/kg: P = 0.0203, CRS + Saline vs. CRS + 10 U/kg: P = 0.0016, CRS + Saline vs. CRS + 30 U/kg: P = 0.0001 of total time of immobility in d; Naïve + Saline vs. CRS + Saline: P = 0.0002, CRS + Saline vs. CRS + 3 U/kg: P = 0.0147, CRS + Saline vs. CRS + 10 U/kg: P = 0.0206, CRS + Saline vs. CRS + 30 U/kg: P = 0.012 of sucrose preference in e. f, g CRS mice in the subgroups of 10 and 30 U/kg BoNT/A facial pre-injection exhibited attenuated depressive-like behaviors compared to that in the subgroup treated with saline in the group of facial pre-treatment 3 days prior to the restraint end. n = 10 animals from the subgroup of Naïve + Saline, and n = 9 animals from the other four subgroups, respectively. One-way ANOVA followed by Dunnett’s multiple comparisons test comparing each subgroup with the subgroup of CRS mice with saline injection, F _{(4, 41)} = 4.239, P = 0.0058 and F _{(4, 41)} = 4.353, P = 0.005 in f; F _{(4, 41)} = 6.176, P = 0.0006 in g. The P-value of Dunnett’s multiple comparisons: Naïve + Saline vs. CRS + Saline: P = 0.0021, CRS + Saline vs. CRS + 3 U/kg: P = 0.3919, CRS + Saline vs. CRS + 10 U/kg: P = 0.016, CRS + Saline vs. CRS + 30 U/kg: P = 0.0422 of latency of immobility in f; Naïve + Saline vs. CRS + Saline: P = 0.0137, CRS + Saline vs. CRS + 3 U/kg: P = 0.8188, CRS + Saline vs. CRS + 10 U/kg: P = 0.009, CRS + Saline vs. CRS + 30 U/kg: P = 0.0216 of total time of immobility in f; Naïve + Saline vs. CRS + Saline: P = 0.0002, CRS + Saline vs. CRS + 3 U/kg: P = 0.6062, CRS + Saline vs. CRS + 10 U/kg: P = 0.0205, CRS + Saline vs. CRS + 30 U/kg: P = 0.0146 of sucrose preference in g. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001