NOTCH4 signaling controls EFNB2-induced endothelial progenitor cell dysfunction in preeclampsia

Area of Science:

• Obstetrics and Gynecology
• Vascular Biology
• Cellular Signaling

Background:

• Preeclampsia is linked to endothelial dysfunction, potentially treatable by endothelial progenitor cells (EPCs).
• The DLL4/NOTCH-EFNB2 pathway may impair EPC activity in preeclampsia pathogenesis.
• NOTCH1 and NOTCH4 are known receptors for DLL4/NOTCH, crucial for angiogenesis.

Purpose of the Study:

• To determine whether NOTCH1 or NOTCH4 is the specific receptor for the DLL4/NOTCH-EFNB2 cascade.
• To investigate the role of this cascade in preeclampsia and its effect on EPCs.

Main Methods:

• Examined EFNB2 expression following NOTCH1 or NOTCH4 downregulation, with or without DLL4 stimulation.
• Assessed the impact of NOTCH4 on EPC biological activity.
• Analyzed NOTCH4 and EFNB2 expression in EPCs from preeclampsia and normal pregnancies.

Main Results:

• NOTCH4 downregulation decreased EFNB2 expression, unaffected by DLL4/NOTCH activation.
• NOTCH1 silencing moderately increased EFNB2 expression, further elevated by DLL4/NOTCH activation.
• NOTCH4 downregulation enhanced EPC biological activity, similar to EFNB2 silencing.
• NOTCH4 and EFNB2 levels were elevated in preeclampsia EPCs compared to controls.

Conclusions:

• NOTCH4 is identified as the specific receptor for the DLL4/NOTCH-EFNB2 cascade, not NOTCH1.
• Inhibition of the NOTCH4/DLL4/NOTCH-EFNB2 cascade may enhance EPC angiogenic properties.
• Targeting this pathway offers a potential therapeutic strategy for promoting angiogenesis in preeclampsia.