A Study On The Sequential Expression Of GFAP, ApoE, S-100, Inflammatory Factor And Metabonomics After Brain Contusion In Rats

Objective: To study the sequential expression of GFAP, Apo E, S-100, GFAP, 1H-NMR and inflammatory factors by immunohistochemistry molecular biology technique, enzyme linked immunosorbent assay and computer image analysis. To investigate the temporal expression of GFAP, S-100, Apo E protein and inflammatory factors with traumatic brain injury in rats and detect serum biomarker in brain damage by 1H-NMR technology. Methods: 60 healthy male SD rats were randomly divided into normal control group(n=10), sham group(n=10) and brain injury group(n=40). Damage group in the 0.5h, 1d, 3d, 7d time points(n=10). 1) Based on establishing focal rat cerebral contusion model, We observe the changes of brain tissue morphology using optical microscope, detect Apo E, S-100 and GFAP in brain homogenate of three groups rats by immunohistochemistry staining method, molecular biology technique and enzyme linked immunosorbent assay. 2) The inflammatory factors in brain homogenate of rats were detected by enzyme linked immunosorbent assay in three groups. 3) Plasma biomarkers of brain contusion rats were determined by 1H-NMR. Results: 1)In the normal control group and sham group, the neurons in the cerebral cortex of rats were in a few neurons or astrocytes, and GFAP was weakly positive. The 0.5h group of rats with cerebral contusion, yellow brown granules appear in the cortex contusion foci. The positive cells in the 1d to 3d group were gradually increased, and the 7d group was observed in the cytoplasm of neurons and astrocytes. The expression of GFAP protein and m RNA in normal control group and sham injured group were not significantly changed, and the GFAP protein and m RNA in brain injury rats increased significantly. 2) TNF-α, IL-6, MMP-9 contents were significantly higher than normal control,The difference was statistically significant(P<0.05). 3) Cr, Cho, Lac, Glu contents increased, and NAA peak decreased. Conclusion: 1) Feeney’s free fall impact method can make a stable animal model of focal cerebral contusion. 2) The expression of GFAP, S-100, Apo E and inflammatory factors in the brain contusion of rats had a certain time regularity and reached the peak in 7d. So it can be used to deduce the time of cerebral contusion. 3) 1H-NMR can evaluate the severity of brain injury. The contents of Lac, Cr and Cho were significantly increased, and NAA was significantly decreased, which indicated that the neurons were damaged, and the energy metabolism was abnormal.