Objective: To study influence on angiogenesis of placenta by gene silencing of netrin-1.
Methods: Netrin-1 gene in human umbilical vein endothelial cells (HUVEC) and placenta of pregnant rats were silenced by RNA interference. The following methods were used in this study, including the phenytetrazoliumromide (MTT) for viability, clone formation for proliferation, transwell for migration, and tube formation for angiogenesis in vitro. The change of fetal growth was recorded. Placental microvessel density in pregnant rats was measured by immunohistochemical CD(34) staining in vivo.
Results: (1) HUVEC: viability and proliferation of HUVEC were remarkably inhibited by gene silencing of netrin-1, which number of clone formation, migration cell, tube formation were from (69 ± 6)%, 86 ± 17, 37 ± 9 decreased to (46 ± 5)%, 46 ± 13 and 17 ± 5 (P < 0.05) respectively. (2) Placenta of pregnant rats: after netrin-1 gene silenced, fetal weight were decreased from (2.39 ± 0.17) g to (2.12 ± 0.10) g (P < 0.05). Placental microvessel density was decreased from (258 ± 38)/mm(2) to (197 ± 32)/mm(2) in vivo (P < 0.05).
Conclusions: Gene silencing of netrin-1 could inhibit viability, proliferation, migration, tubal formation of HUVEC and angiogenesis of placenta. Netrin-1 plays an important role in regulating angiogenesis in placenta.