Slit2 suppresses endothelial cell proliferation and migration by inhibiting the VEGF-Notch signaling pathway

Abstract

Slit homolog 2 (Slit2) is distributed in various tissues and participates in numerous cellular processes; however, the role of Slit2 in the regulation of angiogenesis remains controversial, since it has previously been reported to exert proangiogenic and antiangiogenic activities. The present study aimed to investigate the effects of Slit2 on vascular endothelial cell proliferation and migration in vitro, and to reveal the possible underlying signaling pathway. Aortic endothelial cells were isolated from Sprague Dawley rats and cultured. Cell proliferation assay, cell migration assay, immunocytochemistry and small interfering RNA transfection were subsequently performed. The results demonstrated that exogenous Slit2 administration markedly suppressed TNF-α-induced endothelial cell proliferation and migration in vitro. In addition, TNF-α application upregulated the protein expression levels of vascular endothelial growth factor (VEGF) and Notch in RAECs, whereas Slit2 administration downregulated VEGF and Notch expression in RAECs cultured in TNF-α conditioned medium. Further studies indicated that knockdown of VEGF suppressed the effects of TNF-α on the induction of RAEC proliferation and migration. VEGF knockdown-induced inhibition of RAEC proliferation and migration in TNF-α conditioned medium was also achieved without Slit2 administration. Furthermore, VEGF knockdown markedly decreased Notch1 and Notch2 expression. These results indicated that Slit2 suppresses TNF-α-induced vascular endothelial cell proliferation and migration in vitro by inhibiting the VEGF-Notch signaling pathway. Therefore, Slit2 may inhibit the proliferation and migration of endothelial cells during vascular development.

Slit2/Robo4 axis may contribute to endothelial cell dysfunction and angiogenesis disturbance in systemic sclerosis

“…Our in vitro findings show that the administration of exogenous Slit2 to H-MVECs exerts potent antiangiogenic properties similar to those elicited by Slit2-enriched SSc sera, as testified by the ability to reduce cell viability, wound healing capacity and capillary-like tube formation. This is in agreement with recent reports showing that Slit2 inhibits chemotaxis, migration and invasion of different types of cancer cells42 and suppresses TNF-α-induced cell proliferation and migration of rat aortic endothelial cells 43. Strikingly, we observed that blocking elevated Slit2 in SSc sera resulted in significantly attenuated antiangiogenic effects on administration to H-MVECs.…”

Uric acid promotes oxidative stress and enhances vascular endothelial cell apoptosis in rats with middle cerebral artery occlusion

“…( B ) Statistical analysis of the apoptotic cell rate in each group. Aortic endothelial cells were isolated from rats as previously described [ 17 ]. ** P <0.01 compared with Sham group.…”

“…Aortic endothelial cells were isolated from rats as previously described [ 17 ]. Briefly, rats were anesthetized and killed by rapid cervical dislocation and an incision was quickly made in the abdominal skin, in order to expose the aorta, which was perfused with PBS containing heparin and was then resected.…”

The regulatory roles of VEGF‐Notch signaling pathway on aplastic anemia with kidney deficiency and blood stasis

“…23 It has been reported that endothelial cells promote the proliferation and differentiation of neural stem cells, possibly by activating the VEGF-Notch pathway, 24 while Slit2 suppress endothelial cell proliferation and migration by inhibiting the VEGF-Notch signaling pathway. 25 The inhibition of cell growth, migration, and promotion of apoptosis induced by delta-tocotrienol are associated with decreased expression of Notch-1 and VEGF. 26 Meanwhile, the inhibition of either VEGF or Notch pathway can regulate cell proliferation and apoptosis through suppressing the expression of cell cycle regulators.…”