Fig. 6.

Spinal cord injury (SCI)-induced astrogliosis and inflammation at the injury site are suppressed by CR8 treatment. (a, b) Western blot analysis shows that CR8 significantly reduced the SCI-induced up-regulation of ionized calcium-binding adaptor molecule 1 (Iba-1), gelectin3, and glial fibrillary acidic protein (GFAP) protein at 5 weeks post-injury. Representative immunoblots are shown in (a). *p < 0.05 compared with Sham group (n = 4 for Sham groups); #p < 0.05 compared with SCI vehicle (Veh) group (n = 5 for SCI groups). (c) GFAP-positive cells were significantly increased at 5 weeks post-injury in both saline- (n = 8) and CR8-treated rats (n = 9). CR8 treatment resulted in a significantly reduced number of GFAP⁺ astrocytes. *p < 0.05 compared with Sham group (n = 3 for Sham groups); #p < 0.05 compared with SCI Veh group. (d) The image shows lesion boundary between spared tissue and lesion cavity, as indicated by GFAP staining. (e) Quantification of total Iba-1⁺ microglial cells showed significant increase in the injured spinal cord (n = 5 for SCI Veh, n = 4 for SCI CR8, *p < 0.05 compared with Sham group), but there is no difference between SCI Veh and SCI CR8 groups. (f) Representative Iba-1 immunohistochemical images displayed resting (ramified morphology) or activated (hypertrophic and bushy morphology) microglial phenotypes and the corresponding Neurolucida reconstructions. (g, h) Unbiased stereological quantitative assessment of microglial phenotypes in the spared tissue and lesion area of the spinal cord 7 days post-injury. There was no significant difference in the number of total microglia and 3 microglial phenotypes in the lesion area, as well as ramified microglia in the spared tissue across groups. CR8 treatment demonstrated significantly reduced numbers of activated microglia in the spared tissue compared with SCI Veh rats (*p < 0.05 SCI CR8 vs SCI Veh; n = 4–5/group). GAPDH = glyceraldehyde 3-phosphate dehydrogenase; Gal3 = galectin 3