Angiopoietin-like 4 binds neuropilins and cooperates with VEGF to induce diabetic macular edema
Akrit Sodhi, … , Daoyuan Lu, Silvia Montaner
Akrit Sodhi, … , Daoyuan Lu, Silvia Montaner
Published September 23, 2019
Citation Information: J Clin Invest. 2019;129(11):4593-4608. https://doi.org/10.1172/JCI120879.
View: Text | PDF
Research Article Angiogenesis Ophthalmology

Angiopoietin-like 4 binds neuropilins and cooperates with VEGF to induce diabetic macular edema

Abstract

The majority of patients with diabetic macular edema (DME), the most common cause of vision loss in working-age Americans, do not respond adequately to current therapies targeting VEGFA. Here, we show that expression of angiopoietin-like 4 (ANGPTL4), a HIF-1–regulated gene product, is increased in the eyes of diabetic mice and patients with DME. We observed that ANGPTL4 and VEGF act synergistically to destabilize the retinal vascular barrier. Interestingly, while ANGPTL4 modestly enhanced tyrosine phosphorylation of VEGF receptor 2, promotion of vascular permeability by ANGPTL4 was independent of this receptor. Instead, we found that ANGPTL4 binds directly to neuropilin 1 (NRP1) and NRP2 on endothelial cells (ECs), leading to rapid activation of the RhoA/ROCK signaling pathway and breakdown of EC-EC junctions. Treatment with a soluble fragment of NRP1 (sNRP1) prevented ANGPTL4 from binding to NRP1 and blocked ANGPTL4-induced activation of RhoA as well as EC permeability in vitro and retinal vascular leakage in diabetic animals in vivo. In addition, sNRP1 reduced the stimulation of EC permeability by aqueous fluid from patients with DME. Collectively, these data identify the ANGPTL4/NRP/RhoA pathway as a therapeutic target for the treatment of DME.

Authors

Akrit Sodhi, Tao Ma, Deepak Menon, Monika Deshpande, Kathleen Jee, Aumreetam Dinabandhu, Jordan Vancel, Daoyuan Lu, Silvia Montaner

×

Figure 5

ANGPTL4 and VEGF cooperate in the induction of the increase in retinal vascular permeability.

Options: View larger image (or click on image) Download as PowerPoint
ANGPTL4 and VEGF cooperate in the induction of the increase in retinal v...
(A and B) EC permeability assay upon treatment of HUVECs with optimal (A) or suboptimal (B) concentrations of rhANGPTL4, rhVEGFA, or both. (C) Vascular permeability assay following intraretinal injection with 1 μl of PBS or rmVEGFA, rmANGPTL4, or both. (D and E) KDR phosphorylation on Tyr951 and Tyr1059 upon treatment of HUVECs (D) or hREC (E) with different doses of rhANGPTL4 (μg/mL), rhVEGFA (ng/mL), or both. (F) EC permeability assay upon treatment with rhANGPTL4, rhcANGPTL4, rhnANGPTL4 (μg/mL), or none (control) in HUVECs. VEFGA (50 ng/mL) served as a control. (G) Destabilization of the vascular AJs (β-catenin staining) and TJs (ZO1 staining) of hREC monolayers treated for 6 hours with PBS (control) or rhcANGPTL4 (5 μg/mL). Original magnification, ×20. (H) KDR phosphorylation in Tyr951 and Tyr1059 upon treatment of HUVECs with rhcANGPTL4 (μg/mL). One-way ANOVA (A, B, C, F). **P < 0.01; ***P < 0.001. Experiments were repeated at least 3 times.