Fig 1: orsal root ganglion (DRG) injection of C-reactive protein (CRP) siRNA inhibits nerve injury induced pain hypersensitivity and phosphorylated Syk (pSyk)/NLR family pyrin domain containing 3 (NLRP3) signaling activation. a,b) A preintraganglionic injection of CRP siRNA attenuated chronic constriction injury (CCI) induced mechanical allodynia (a) and thermal hyperalgesia (b). Ctrl siRNA is the control siRNA. Administration was performed 3 and 1 days before CCI operation. Two-way ANOVA, n = 10 per group, * p < 0.05, ** p < 0.01 versus the sham group, # p < 0.05, ## p < 0.01, versus the CCI + Ctrl siRNA and the sham group. c) Western blot and immunostaining analysis of the effect of CRP siRNA on CRP protein levels and cellular expression in the DRG from CCI 15 d rats. d,e) Western blot analysis (d) and quantification (e) of the effect of CRP-specific siRNA on pSyk, NLRP3, IL-1ß, and IL-18 protein levels in the DRG from CCI rats 15 d after the operation. One-way ANOVA, n = 6 per group, * p < 0.05, ** p < 0.01 versus the sham group; # p < 0.05, ## p < 0.01 versus the CCI + Ctrl siRNA. f–i) Immunostaining analysis of the effect of CRP-specific siRNA on pSyk, NLRP3, IL-1ß, and IL-18 cellular expression in DRG neurons from CCI rats 15 d after the operation. j,k) Western blot analysis (j) and quantification (k) of the effect of Fc?RI/pSyk signaling inhibition on the CRP expression level and Stat3 phosphorylation level in the DRG from CCI rats 21 d after nerve injury. One-way ANOVA, n = 4 per group, * p < 0.05, ** p < 0.01 versus the sham group, # p < 0.05 versus the CCI group and the CCI + Veh group. l) Schematic illustration demonstrates CRP/Fc?RI positive feedback proinflammatory signaling of neuropathic pain induced by nerve injury.
Fig 2: hronic constriction injury (CCI) increased C-reactive protein (CRP) expression in the dorsal root ganglions (DRGs) and CRP-induced pain in rats. a) Western blot analysis and quantification of CRP protein levels in DRGs from sham, CCI 7 d, 15 d, and 21 d rats after surgery. One-way ANOVA, n = 6 per group, * p < 0.05 versus the sham group. b) Immunostaining of CRP in the DRGs of sham and CCI 7 d, CCI 15 d, and CCI 21 d rats. c) The positive rates of CRP in DRG neurons from sham, CCI 7 d, CCI 15 d, and CCI 21 d rats. Scale bars: 50 µm. One-way ANOVA, n = 4 per group, * p < 0.05, ** p < 0.01 versus the sham group. d,e) CRP induced mechanical (d) and thermal (e) hyperalgesia in naive rats. Changes in the paw withdrawal mechanical threshold (e) and the paw withdrawal thermal latency (e) in the ipsilateral hindpaw after intradermal injection. n = 10 per group, two-way ANOVA, * p < 0.05, ** p < 0.01 versus the Veh group. f,g) CRP-induced mechanical (f) and thermal (g) hyperalgesia was alleviated in conditional knockout (CKO) rats. Changes in the paw withdrawal mechanical threshold (f) and the paw withdrawal thermal latency (g) in the ipsilateral hindpaw after intradermal injection. n = 7 per group, two-way ANOVA, * p < 0.05, ** p < 0.01 versus the littermate group. h,i) CRP-sensitized naive rats to IgG-immune complex (IgG-IC) induced mechanical (h) and thermal (i) hyperalgesia. Changes in the paw withdrawal mechanical threshold (h) and the paw withdrawal thermal latency (i) in the ipsilateral hindpaw after intraplantar injection. n = 9 per group, two-way ANOVA, * p < 0.05, ** p < 0.01 versus the Veh group; ## p < 0.01 versus the IgG-IC + CRP group.
Fig 3: C-reactive protein (CRP) overexpression induced pain and increased neuronal Fc-gamma-receptor type I (Fc?RI) related neuroinflammation in dorsal root ganglions (DRGs). a,b) CRP overexpression in the DRG induced Fc?RI-mediated mechanical (a) and thermal hyperalgesia (b) in rats. Two-way ANOVA, n = 9 per group, * p < 0.05, ** p < 0.01, versus the naive group and littermate + Ad Ctrl group. # p < 0.05, ## p < 0.01, versus littermate + Ad-CRP-OV. c) Western blot showing the expression levels of CRP overexpression and activation of Sykphosphorylated NF-kappa B p65 subunit (NF-?B p65) signals in DRGs of littermate and conditional knockout (CKO) rats after DRG injection of AAV2/9-hSyn-CRP. d) Data summary of the expression levels of CRP, phosphorylated Syk (pSyk), and pNF-?B p65 in the DRGs of littermate and CKO rats after DRG injection of AAV2/9-hSyn-CRP. One-way ANOVA, n = 5 per group, ** p < 0.01 versus the naive group and littermate + Ad-Ctrl group, # p < 0.05 versus the littermate + Ad-CRP-OV group. e) Coexpression of the ZsGreen tag with PGP9.5 in neurons after DRG injection of AAV2/9-hSyn-CRP. f) The positive rate of ZsGreen tag-positive neurons in the littermate + Ad Ctrl group, littermate + Ad-CRP-OV group, and CKO + Ad-CRP-OV group. n = 4 rats per group. g) Coexpression of the ZsGreen tag with CRP after DRG injection of AAV2/9-hSyn-CRP. h) Data summary of CRP-positive neurons in the DRGs of littermate and CKO rats after DRG injection of AAV2/9-hSyn-CRP. i) Coexpression of the ZsGreen tag with pSyk in neurons after DRG injection of AAV2/9-hSyn-CRP. j) Data summary of pSyk-positive neurons in the DRGs of littermate and CKO rats after DRG injection of AAV2/9-hSyn-CRP. One-way ANOVA, n = 4 per group, ** p < 0.01 versus the littermate + Ad Ctrl group, # p < 0.05 versus the littermate + Ad-CRP-OV group. Scale bars: 50 µm (e,g,h).
Supplier Page from Sino Biological, Inc. for Rat CRP / C-Reactive Protein (His Tag)