Spatiotemporal release of VEGF from biodegradable polylactic-co-glycolic acid microspheres induces angiogenesis in chick chorionic allantoic membrane assay

Publication date: Available online 8 March 2019Source: International Journal of PharmaceuticsAuthor(s): Omar Qutachi, Anthony J. Bullock, Giulia Gigliobianco, Sheila MacNeilAbstractWhile vascular endothelial growth factor (VEGF) is an acknowledged potent pro-angiogenic agent there is a need to deliver it at an appropriate concentration for several days to achieve angiogenesis. The aim of this study was to produce microspheres of biodegradable polylactic-co-glycolic acid (PLGA) tailored to achieve sustained release of VEGF at an appropriate concentration over seven days, avoiding excessive unregulated release of VEGF that has been associated with the formation of leaky blood vessels. Several formulations were examined to produce microspheres loaded with both human serum albumin (HSA) and VEGF to achieve release of VEGF between 3 and 10 ng per ml for seven days to match the therapeutic window desired for angiogenesis. In vitro experiments showed an increase in endothelial cell proliferation in response to microspheres bearing VEGF. Similarly, when microspheres containing VEGF were added to the chorionic membrane of fertilised chicken eggs, there was an increase in the development of blood vessels over seven days in response, which was significant for microspheres bearing VEGF and HSA, but not VEGF alone. There was an increase in both blood vessel density and branching –both signs of proangiogenic activity. Further, there was clearly migration of cells to the VEGF loaded micro...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research