Figure 4
Spinal and dorsal root ganglia (DRG) pro-and anti-inflammatory markers expression. (A and B) All rats reveal similar BL threshold values. After CCI, bilateral allodynia compared to sham treatment is observed. On day 10, i.t. pretreatment with D-mannose (50 μg) or equivolume saline followed three days later by i.t. pDNA-IL-10 (25 μg; closed squares; n = 7) or equivolume saline (closed circles; n = 4) is given. Saline-CCI treated animals (open diamonds; n = 3) remained allodynic compared to sham-D-mannose (open squares; n = 3) or sham-saline (open circles; n = 6) treated animals (ipsilateral, F(2,9) = 28.79, P <0.0001; contralateral, F(2,9) = 19.7, P < 0.001). Pretreatment with D-mannose (50 μg) followed by pDNA-IL-10 (25 μg) reversed bilateral allodynia compared to CCI-control groups (ipsilateral, F(4,126) = 30.27, P < 0.0001; contralateral, F(4,126) = 35.75; P < 0.0001). (C) Day 29 immunohistochemical examination revealed increased IL-10 immunoreactivity (IR) in lumbar spinal cord with D-mannose (50 μg) pretreatment followed by pDNA-IL-10 compared to non-mannose treated control groups (F(2, 5) = 34.23, P < 0.01). (D-F) Corresponding fluorescent images of the analyzed data (red = IL-10, blue = cell nuclei). (G) Decreased IL-1β IR in the ipsilateral lumbar spinal cord compared to non-mannose treated control groups (F(2,5) = 10.67, P < 0.05). (H-J) Corresponding fluorescent images (red = IL-1β, blue = cell nuclei). (K) Increased DRG IL-10 IR in rats pretreated with D-mannose compared to non-mannose treated control groups (F(2, 5) = 10.35, P < 0.05). (L-N) Corresponding fluorescent images (red = IL-10, blue = cell nuclei). (O, Q) Contralateral spinal cord and DRG reveal elevated IL-10 IR, while (P) complete IL-1β IR suppression in the contralateral spinal cord is observed following D-mannose pretreatment. *P < 0.05; **P < 0.01; ***P < 0.0001; images 10X; scale bar = 100 μm.