Influences of bFGF and EGF on the proliferation and differentiation of endogenous neural stem cells after cerebral infarction in human

OBJECTIVE: To investigate the relationship of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) and proliferation of endogenous neural stem cells (NSCs) after human cerebral infarction. METHODS: Paraffin-embedded brain tissues of 22 human fatal cases of CI from the brain tissues around subventricular zone and subgranular layer zone were stained with HE and immunohistochemistry stain. The endogenous neural stem cells were marked by nestin. The expression changes of EGF, bFGF and nestin in the perihematomal tissues were analysed with the SPSS 13.0 system. RESULTS: (1) Compared with the controls, the number of nestin-positive cells increased at 24 - 72 h (14 +/- 6)/HP in the ipsilateral SVZ and began to rise at 4.5 - 10 h (11 +/- 5)/HP in the ipsilateral SGZ, reached maximum at 120 - 144 h ((38 +/- 7)/HP in the SVZ, (54 +/- 17)/HP in the SGZ, and decreased markedly at 216 - 336 h, but it was still elevated compared with the controls (P < 0.05). (2) The number of bFGF-positive cells increased at 4.5 - 10 h (8.1 +/- 2.9)/HP in the SVZ, (19.0 +/- 8.2)/HP in the SGZ, reached maximum at 24 - 70 h (15.6 +/- 3.5)/HP in the SVZ, (32.0 +/- 5.7)/HP in the SGZ and decreased at 72 - 96 h, but it was still elevated compared with the controls (P < 0.05). (3) The number of EGF-positive cells increased at 4.5 - 10 h (4.3 +/- 1.6)/HP in the SVZ, (7.0 +/- 3.7)/HP in the SGZ, reached maximum at 120 - 144 h (27.0 +/- 1.4)/HP in the SVZ, (51.5 +/- 4.9)/HP in the SGZ and decreased at 216 - 336 h, but it was still elevated compared with the controls (P < 0.05). CONCLUSIONS: Perhaps the increased expression of EGF and bFGF after CI was a reaction of endogenous reparation and it correlated with the proliferation and endogenous of neural stem cells in human.