Enhancing effects of perlecan or vascular endothelial growth factor-165 on angiogenesis in mice

Abstract

To explore the angiogenesis-promoting effects of perlecan or vascular endothelial growth factor (VEGF) at different time points through quantitative analysis of microvessel density (MVD). Four kinds of scaffolds: open-cell polylactic acid (OPLA) (control), OPLA + VEGF-165, OPLA + perlecan and OPLA + VEGF-165 + perlecan were implanted into mice. At Weeks 1, 2, 3, 4, 6 and 8, OPLA was harvested and then HE and immunocytochemistry were employed to detect the angiogenesis-promoting effects of scaffold. MVD of each group was appraised by the Tukey test. The scaffolds exhibited excellent biocompatibility with tissue. Numerous vessels were spotted obviously around the implants, especially at Week 8. And the OPLA scaffold degraded with the elapsing of time and its inner part was divided into many sections along with the ingrowth of vessels. Compared with the other three groups, the MVD of the OPLA + VEGF-165 + perlecan group was the highest at all time points. There were statistical differences between the OPLA + VEGF-165 + perlecan and OPLA groups at Week 1 (3.30 ± 0.42 vs 1.80 ± 0.29); MVD of the OPLA + VEGF-165 + perlecan group was thrice as much as the OPLA group at Week 3 (11.70 ± 0.87 vs 4.50 ± 0.34); at Week 8, MVD of the OPLA + VEGF-165 + perlecan group was more than thrice as much as the OPLA group (31.40 ± 1.35 vs 9.90 ± 0.67). Angiogenesis is synergistically enhanced by the combined application of VEGF-165 and perlecan in mice.