RESUMO
This study is to observe the effect of ilexonin A (IA) on the expression of basic fibroblast growth factor (bFGF) and growth associated protein-43 (GAP-43), and neurogenesis after cerebral ischemia-reperfusion in rats and explore its possible mechanism of protecting neuronal injury. Models of middle cerebral artery occlusion (MCAO) were established in SD rats. Before and after two hours ischemia-reperfusion, IA (20 and 40 mg x kg(-1)) was injected immediately and on 3, 7, 14, and 28 d once a day. The neurological severity was evaluated by neurological severity scores (NSS); neuronal injury in the boundary zone of the infarction area was evaluated by TUNEL and Niss1 staining. The expressions of bFGF and GAP-43 and neurogenesis were evaluated by Western blotting and 5-bromodeoxyuridine (Brdu) fluorescence staining, respectively. After treatment with IA, the NSS of treatment groups were lower than that of the models (3 and 7 d). The number of TUNEL positive neurons decreased and Nissl positive neurons increased at the same time (3 d). The expressions of bFGF and GAP-43 increased significantly in the boundary zone of the infarction area when compared to model group. Moreover, IA markedly enhanced the neurogenesis in the brain after ischemia-reperfusion, which revealed an increase of Brdu/NeuN positive cells in the boundary zone of the infarction area. The possible mechanism of protecting neuronal injury of IA may be related to inhibition on neuronal apoptosis, upregulation of bFGF and GAP-43, and neurogenesis in boundary zone of infarction after cerebral ischemia-reperfusion.
Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Proteína GAP-43/metabolismo , Neurogênese/efeitos dos fármacos , Traumatismo por Reperfusão/metabolismo , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/etiologia , Bromodesoxiuridina/metabolismo , Infarto da Artéria Cerebral Média/complicações , Masculino , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Compostos Orgânicos/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/etiologiaRESUMO
OBJECTIVE: To observe time points of the expressions of basic fibroblast growth factor (bFGF), growth associated protein-43 (GAP-43) and neurogenesis after cerebral ischemia/reperfusion in rats and explore its possible mechanism of neurogenesis. METHODS: Models of middle cerebral artery occlusion (MCAO) were established in SD rats which were divided into 3 d, 7 d, 14 d and 28 d groups (n = 6). The neurological severity was evaluated by neurological severity scores (NSS) and scores of motor test (SMT). Neuronal injury in the boundary zone of the infarction area was evaluated by TUNEL and Nissl staining; The expressions of bFGF and GAP-43 and neurogenesis were evaluated by Western blot and 5-bromodeoxyuridine (Brdu) fluorescence staining, respectively. RESULTS: It showed up neurologic impairment and motor dysfunction after cerebral ischemia/reperfusion in rats at 3 d, the numbers of neuron apoptosis also peaked at 3d, the protein levels of bFGF and GAP-43 were significantly increased in time-dependent manner, peaked at 7 d and then decreased gradually, meanwhile, Brdu and NeuN double fluorescence staining displayed scattered Brdu-and NeuN-positive cells in the boundary zone of the infarction area. CONCLUSION: These results suggest that the upregulation of bFGF and GAP-43 may contribute to the neurogenesis after cerebral ischemia/reperfusion.