Fig. 2
Spinal Peli1 contributes to the initiation and maintenance of neuropathic pain. a, b Timeline schematic of experimental paradigm. c Effective knockdown of Peli1 in vivo by lentiviral vectors carrying Peli1 shRNA (shPeli1) was examined using western blot. Lentiviral vectors carrying scrambled shRNA (shScr) were used as negative control (n = 4–6). One-way ANOVA (F3,18 = 13.3). d, e qPCR and western blot analysis showing the inhibitory effect of Peli1 shRNA on CCI-induced increases in Peli1 mRNA (d, n = 4–5) and protein (e, n = 4–5). One-way ANOVA [(d) F5,20 = 47.3; (e) F5,20 = 48]. f Immunofluorescence showing intrathecal injection of Peli1 shRNA eliminates CCI-induced increase in Peli1 immunoreactivity (scale bar 50 μm, n = 4). g, h Thermal sensitivity and mechanical allodynia were tested prior to surgery and on days 3, 5, 7, 11, and 14 after surgery. Peli1 shRNA (i.t., 3 days prior to the beginning of CCI, indicated by arrows) suppresses CCI-induced decreases in PWL (g) and PWT (h) values (n = 5). Repeated measures two-way ANOVA [(g) interaction F25,144 = 14.6; time F5,144 = 15.9; treatment F5,144 = 231.9 (h) interaction F25,144 = 3.5; time F5,144 = 21.7; treatment F4,144 = 76.5]. i–k Mice were given with Peli1 siRNA (siPeli1) and negative siRNA (siNeg) once daily from postoperative days 5 to 7 (indicated by arrows). Ipsilateral lumbar dorsal spinal tissues were harvested 4 h after the last siRNA injection for detection of Peli1 expression (i, n = 4). Intrathecal injection of peli1 siRNA reverses established thermal hyperalgesia (j) and mechanical allodynia (k) on day 5 and 7 following CCI (n = 5). Repeated measures two-way ANOVA [(j) interaction F20, 120 = 9.6; time F4,120 = 44.4; treatment F5,120 = 175.5 (k) interaction F20,120 = 4.2; time F4,120 = 19.8; treatment F5,120 = 51]. Results are expressed as the Mean ± SEM. **p < 0.01, ***p < 0.001 compared with indicated group. #p < 0.05 compared with CCI and CCI plus scrambled shRNA. ##p < 0.05 compared with CCI and CCI plus negative siRNA