Expression changes of VEGF and GFAP in cultured rat astrocytes after irradiation by X-ray and their significances
10.3760/cma.j.issn.1671-8925.2013.04.010
- VernacularTitle:X线照射后体外培养星形胶质细胞VEGF和GFAP表达变化及意义
- Author:
Gui-Juan ZHOU
1
;
Hai-Wei HUANG
;
Xiao-Hong WU
;
Meng-Meng WU
Author Information
1. 中山大学附属第一医院神经科
- Keywords:
X-ray;
Radiation brain injury;
Astrocyte;
Glial fibrillary acid protein;
Vascular endothelial growth factor
- From:
Chinese Journal of Neuromedicine
2013;12(4):369-375
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the time-and dose-related expressions of vascular endothelial growth factor (VEGF) and glial fibrillary acid protein (GFAP) in cultured rat astrocytes after irradiation by X-ray,and discuss the possible relationship between astrocytes and radiation brain injury (RBI).Methods Rat astrocytes primarily cultured in vitro were exposed to X-ray at various doses (5,10,15 and 20 Gy) and kept culturing for 48 h,and some other rat astrocytes primarily cultured in vitro were exposed to 20 Gy and kept culturing for 4,12,24 and 48 h,respectively; normal control groups (without radiation) were used in all the above experiments.Immunofluorescence staining was employed to detect the level of GFAP and observe the cell morphology changes in each group; DAPI staining was used to observe the apoptosis of astrocytes; VEGF and GFAP expressions were detected by Western blotting.Results As compared with astrocytes in the normal control group,astrocytes in the radiation group showed increased number,hyperplasia,deformation,swelling of the cell body,thickening processus and deepened GFAP staining; and these changes became obvious following the increment of time and radiation doses.No significant differences on the astrocyte apoptosis rate were noted between the normal control groups and the radiation groups of different doses (P＞0.05).Western blotting indicated that the irradiation groups of different doses and the 20 Gy radiation groups of different exposing times had significantly different GFAP and VEGF protein expressions (P＜0.05).The expressions of GFAP and VEGF were up-regulated gradually with the increment of radiation doses in astrocytes and times of radiation (P＜0.05); as compared with the control group,20 Gy radiation groups of different exposing times showed time dependent VEGF expression from 4 to 24 h and time dependent GFAP expression from 4 to 48 h (P＜0.05).Conclusion X-ray irradiation can induce the activation of cultured rat astrocytes; VEGF and GFAP expressions in the reactive astrocytes increased in time and dose-dependent manners after X-ray irradiation; VEGF over-expression in reactive astrocytes after irradiation may play an important role in RBI.
