Expression changes of Ang-1, Ang-2, Tie-2 and VEGF in co-culturing of endothelial cells and astrocytes after irradiation by X-ray and their significances

To explore the possible relationship between angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), Tie-2 and vascular endothelial growth factor (VEGF) and radiation brain injury (RBI) and detect the expressions of VEGF, Ang-1, Ang-2 and Tie-2 in co-cultured endothelial cells and astrocytes after an irradiation of X-ray. Murine brain microvascular endothelial cells bEnd.3 and astrocytes were co-cultured in a Transwell culture plate and then exposed to X-ray at various doses (5, 10, 20 and 30 Gy) and cultured for 24 hours. The group without radiation acted as a control. Western blot was used to detect the expressions of VEGF, Ang-1, Ang-2 and Tie-2. As compared with the control group, the expression of VEGF increased in 5, 10, 20 and 30 Gy dose groups [(1.71 ± 0.11), (2.03 ± 0.05), (2.20 ± 0.06), (2.19 ± 0.08) vs (1.26 ± 0.10), P < 0.05]; the expression of Ang-1 decreased in 5, 10, 20 and 30 Gy dose groups [(2.27 ± 0.07), (2.28 ± 0.06), (2.01 ± 0.05), (1.54 ± 0.08) vs (2.46 ± 0.04), P < 0.05]; the expression of Tie-2