Bis(maltolato)oxovanadium(IV) Induces Angiogenesis via Phosphorylation of VEGFR2

Area of Science:

• Biochemistry
• Cell Biology
• Physiology

Background:

• Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) and VEGF-A are critical for angiogenesis.
• Protein Tyrosine Phosphatases (PTPs) regulate VEGFR2 activity and angiogenesis by dephosphorylation.
• Understanding PTPs' role is key to modulating angiogenesis for therapeutic benefit.

Purpose of the Study:

• To investigate the proangiogenic effects of bis(maltolato)oxovanadium(IV) (BMOV), a PTP inhibitor.
• To assess BMOV's impact on in vivo wound healing and in vitro angiogenesis.
• To elucidate the molecular mechanisms underlying BMOV's proangiogenic activity.

Main Methods:

• In vivo wound healing assay in C57BL/6JRj mice.
• In vitro angiogenesis assays using Human Umbilical Vein Endothelial Cells (HUVECs): cell migration, proliferation, and tube formation.
• Ex vivo mouse aortic ring assay.
• Western blot analysis to assess VEGFR2, p38MAPK, and ERK1/2 phosphorylation.

Main Results:

• BMOV significantly accelerated in vivo wound closure by 45%.
• In vitro, BMOV increased HUVEC migration (45%), proliferation (40%), and tube formation (27%) compared to controls, particularly with endogenous VEGF-A.
• BMOV enhanced aortic ring sprouting threefold and increased VEGFR2 and p38MAPK phosphorylation, but not ERK1/2.

Conclusions:

• BMOV effectively promotes wound healing in vivo.
• BMOV stimulates angiogenesis in vitro by enhancing VEGFR2 phosphorylation and downstream signaling in the presence of endogenous VEGF-A.
• BMOV exhibits a stronger proangiogenic effect than when co-administered with exogenous VEGF-A, suggesting a critical role in modulating endogenous pathways.