Long-Term Upregulation of Inflammation and Suppression of Cell Proliferation in the Brain of Adult Rats Exposed to Traumatic Brain Injury Using the Controlled Cortical Impact Model
Figure 2
Upregulation of MHCll+ activated microglia cells in white matter in chronic TBI.
Results indicate that there is an upregulation of activated microglia cells after 8 weeks post TBI in proximal white matter areas. There is an upregulation of MHCll+ cells in the ipsilateral and contralateral side of corpus callosum relative to sham control (Figure 2A). In contrast, upregulation of MHCll+ activated microglia cells in the cerebral peduncle (Figure 2B) and fornix (Figure 2C) is only present in the ipsilateral side as compared with the contralateral and sham control. There were no significant differences between contralateral side and sham control animals in (Figure 2B) and (Figure 2C). ANOVA revealed significant treatment effects as follows: corpus callosum, F2,45 = 5.656; *p<0.05; cerebral peduncle, F2,45 = 27.39, ***p<0.0005, and; fornix, F2,45 = 5.541, *p<0.05. Representative photomicrographs, ipsilateral corpus callosum, sham-control Figure 2E and TBI Figure 2F, ipsilateral cerebral peduncle, sham-control Figure 2G and TBI Figure 2H, and ipsilateral Fornix, sham-control Figure 2I and TBI Figure 2J. Scale bars for Figure 2E, F, G, H, I, J = 1 µm. A summary of MHCll+ estimated volume is presented capturing different subcortical regions; including those proximal and distal from TBI insult (Figure 2D). Chronic TBI greatly upregulates the neuroinflammation in the thalamus expressing the highest upregulation of MHCll+ activated microglia cells, despite its distal subcortical location. Strong expression of MHCll+ activated microglia cells is also detected in the corpus callosum and striatum (Figure 2D).