Figure 7. Effect of curcumin on the spinal JAK2-STAT3 cascade in SNI mice.

(A,B) Mice with peripheral nerve injury were intrathecally injected with AG490 (5 μg) or vehicle (1% DMSO, 5 μl) once a day on days 3–7. The paw withdrawal threshold in response to mechanical stimulation by Von Frey filaments and the duration of lifting/licking of the paw following cold stimulation by acetone were measured in the begining (day 0) and on days 1, 3, 4, 5, 6, and 7 following peripheral nerve injury. *p < 0.05 and **p < 0.01 compared with the SNI +  DMSO group; two-way ANOVA followed by Bonferroni post hoc test; n = 6 per group. (C) Effect of AG490 on the expression of spinal IL-1β mRNA as assessed by real-time PCR on day 7 after surgery. *p < 0.05 and **p < 0.01; one-way ANOVA followed by Bonferroni post hoc test; n = 4 per group. (D,E) SNI resulted in the increased expression of pJAK2 and pSTAT3 in the spinal cord on the seventh day after SNI. The SNI-induced elevation of pJAK2 and pSTAT3 was significantly reversed in the spinal cords of mice following the repeated intraperitoneal injection of curcumin (120 mg/kg). Cropped gels/blots are used in this figure and the immunoblots were obtained from the microgel running in the same experimental conditions. *p < 0.05 and **p < 0.01; one-way ANOVA followed by Bonferroni post hoc test; n = 4 per group. All of the data are shown as the mean ± SEM.