Figure 2

D-mannose improves pDNA-IL-10 anti-allodynia efficacy for 90 days. (A and B) sham operated animals (open triangles; n = 6) versus chronic constriction injury (CCI) animals (open diamonds; n = 7) whereby allodynia persisted to day 10 (ipsilateral, F_(4,28) = 32.87; P < 0.0001; contralateral, F_(4,28) = 37.01; P < 0.0001). On day 10, animals received an i.t. pretreatment of either D-mannose (50 μg; 5 μg), or equivolume saline followed three days later by pDNA-IL-10 (25 μg or 1 μg) or equivolume saline. Following pretreatment with D-mannose (50 μg; closed squares; n = 8), reversal of hindpaw thresholds was observed compared to CCI-saline, or CCI D-mannose (5 μg) injection (ipsilateral, F_{(4, 70)} = 15.87; P < 0.0005; contralateral, F_{(4, 70)} = 20.40; P < 0.001). Full reversal continued for a three-month period beyond the second injection of pDNA IL-10 (25 μg) in those animals given D-mannose (ipsilateral, F_{(3, 384)} = 57.46; P < 0.0001; contralateral, F_{(3, 384)} = 59.20; P < 0.0001). Animals pretreated with the lower dose of D-mannose (5 μg) followed by a second injection of pDNA-IL-10 (25 μg) (closed circles, n = 7) showed partial bilateral reversal. A second injection of a lower dose of pDNA-IL-10 (1 μg: closed triangles; n = 5) produced a transient 11-day reversal compared to other CCI + D-mannose treated rats (ipsilateral, F_(3.17) = 12.71; P < 0.03; contralateral, F_{(3, 17)} = 14.64; P < 0.005).