Effects of electroacupuncture on morphology of neovascularization and expression of angiogenesis-related factors in ischemic brain tissue of cerebral ischemia rats

Abstract

To observe the change of neovascular morphology and angiogenesis related factors in the ischemic cerebral area after cerebral infarction and the intervention effect of electroacupuncture (EA). Wistar rats were randomly divided into model group(n=90), EA group(n=90), sham operation group(n=90) and control group(n=10). The first three groups were further divided into 1 h, 3 h, 6 h, 9 h, 12 h, 24 h, 3 d, 7 d and 12 d subgroups(n=10 in each subgroup). The cerebral infarction model was established by middle cerebral artery occlusion(MCAO). EA(15 Hz, 2 mA) was applied to "Shuigou"(GV26) for 20 min in the EA group. The 1, 3, 6, 9, 12, 24 h subgroups were treated immediately after modeling, the 3, 7, 12 d subgroups were treated once daily for 3, 7 or 12 days. The neovascular endothelial cells were displayed by immunofluorescence double labeling staining. Quantitive real-time PCR and Western blot were applied to detect the changes of basic fibroblast growth factor (bFGF), angiogenin (Ang) -1, 2, platelet-derived growth factor b (PDGF-b) in ischemic brain tissue, respectively. After modeling, CD31 and Ki67 positive cells were first observed at 24 h in the model group, and reached the peak at 3 d, decreased at 7 d. While in the EA group, the CD31 and Ki67 positive cells were first observed at 12 h, and reached the peak at 3 d, and gradually decreased until 12 d. Compared with the control group, the mRNA expressions of bFGF at 9 h-12 h, Ang-1 at 12 h-12 d, Ang-2 at 1 h-12 d and PDGF-b at 1 h, 6 h, 9 h, 24 h-12 d were increased in the model group(P<0.01, P<0.05). After EA, the mRNA expressions of bFGF at 24 h-12 d, Ang-1 at 3 d-12 d, Ang-2 at 3 h-24 h and PDGF-b at 3 h, 6 h, 3 d-12 d were increased(P<0.05, P<0.01). In comparison with the control group, the proteins of bFGF at 24 h, Ang-1 at 6 h-12 d, Ang-2 at 1 h-12 d and PDGF-b at 1 h-7 d were increased in the model group(P<0.05, P<0.01). After EA, the proteins of bFGF at 3 d-12 d, Ang-1 at 3 d-12 d, Ang-2 at 3 h-12 h and PDGF-b at 6 h, 3 d-12 d were increased compared with the model group(P<0.05, P<0.01). EA can up-regulate the expression of angiogenesis-related factors in MCAO rats, which has an important role in the establishment of blood vessel regeneration and collateral circulation, and thus promote the recovery of neurological function.