Increased angiogenesis elicited by boron-containing bioactive glass

HARO DURAND L, VARGAS G, GONGORA A, GOMEZ M, CADENA V, ROMERO M, VERA MESONES R, PORTO LÓPEZ JM, BOCCACCINI AR, ZAGO MP, BALDI A, GORUSTOVICH A.

Leipzig

Congreso; World Conference on Regenerative Medicine; 2011

Translational Centre for Regenerative Medicine (TRM), Leipzig, Germany

Publicado en Regenerative Medicine 2011; 6 (Suppl. 2): 263                            Increasing evidence in the literature shows that the use of bioactive glasses (BGs) in biomaterial-based tissue engineering strategies may improve vascularization and wound healing stimulating the neoformation of blood vessel in response to release of soluble ions. Objective: to evaluate the in vitro and in vivo angiogenic potential of borosilicate BG ionic dissolution products (IDPs). Material and methods: Human umbilical vein endothelial cells (HUVECs) seeded on 96-well tissue culture plates were treated with conditioned media (CM) containing the IDPs of BGs that were prepared by soaking 1% w/v 45S5 BG particles (< 5 µm) of composition (in wt %): 45% SiO2, 24,5% Na2O, 24,5% CaO, 6% P2O5 or 45S5.2B BG containing B2O3 (2% wt) in complete endothelial basal medium M199 in a orbital shaker at 37°C for 24 h. The elementary contents of Ca, Si, B, P and Na in the medium were determined by ICP. Cell proliferation was quantitatively assessed using the [3H]thymidine incorporation assay. The migratory capacity of cells was evaluated by the wound healing assay. Cytokine expression was measured by an ELISA assay. The in vivo angiogenic potential was evaluated using the quail chorioallantoic membrane (CAM) bioassa.  Fertilized eggs of Coturnix coturnix japonica, were incubated in-ovo at 37°C,  cracked at embryonic day 3 (E3) into 6-well plates, and cultured further ex-ovo at 37°C. At E7, 0.5 mL BG-conditioned HBSS solutions were applied to the surface of each CAM. HBSS without BG-IDPs served as control. The embryos were incubated further at 37ºC for 2 and 5 d. An ELISA assay was performed to analyze the endogenous levels of avb3.The plates were incubated with an mAb anti-avb3  (LM609, 1mg/ml) and then incubated with HRP goat anti-mouse IgG and developed in o-phenylenediamide. CAMs from E12 were fixed with 4% paraformaldehyde/2% glutaraldehyde in PBS and observed under light microscopy to count the number of blood vessels branch points within three confined regions of the CAMs. Results and conclusion: Compared to controls, cell proliferation, migration and IL-6 release of HUVECs were statistically significantly increased by CM with BG 45S5.2B. The 45S5.2B-IDPs affected the in vivo angiogenesis increasing the levels of avb3 twofold (0.54±0.07 vs. 0.25±0.05) on CAMs from E9. In addition the number of blood vessels branch points was increased a 26% on CAMs from E12.The robust proangiogenic activity of soluble 45S5.2B BG degradation products appears to have promise for future application in tissue engineering and regenerative medicine.