Combined effect of insulin-like growth factor-1 and CC chemokine ligand 2 on angiogenic events in endothelial cells.

Iana Mayane Mendes Nicácio Viana,Maria Danielma Dos Santos Reis,Salete Smaniotto,Maíra Estanislau Soares De Almeida,Larissa Fernanda De Araújo Vieira,Marvin Paulo Lins,Domenico Ribatti

doi:10.1371/journal.pone.0121249

Iana Mayane Mendes Nicácio Viana, Maria Danielma Dos Santos Reis + Show 5 more

Open Access

https://doi.org/10.1371/journal.pone.0121249

Copy DOI

Abstract

Therapeutic angiogenesis may be applied in medical conditions to promote stimulation of angiogenesis. Angiogenesis is a multistep process, which includes endothelial cell proliferation, migration, and tube formation, which is mediated by various angiogenic polypeptides. Thus, studies that elucidate the cellular mechanisms involved in these processes are necessary to develop novel therapeutic strategies. This study investigated the in vitro effects of the pro-angiogenic factors, insulin-like growth factor-1 (IGF-1) and/or chemokine (CC motif) ligand 2 (CCL2), on endothelial cells. Flow cytometry analysis showed that IGF-1 and CCL2 treatment did not interfere with IGF-1 receptor (IGF-1R) expression, but CCL2 treatment increased CCL2 receptor (CCR2) expression. Immunofluorescence analysis revealed that the IGF-1/CCL2 combination induced a greater increase in fibronectin deposition, but the treatments did not alter the expression of the fibronectin receptors, CD49e and CD44. The interaction of fibronectin with cytokines demonstrated that IGF-1/CCL2 promoted changes in intermediate F-actin remodeling that may result in increased endothelial cell adhesion and cell migration mediated by fibronectin. Furthermore, IGF-1/CCL2 stimulated endothelial cells, grown on fibronectin, to form capillary-like structures and intercellular lumina with greater luminal area. These data suggest that IGF-1/CCL2 combination and a fibronectin matrix may contribute to the angiogenesis process to stimulate adhesion, migration, and tube formation by endothelial cells as a result of F-actin remodeling.

Highlights

The endothelium is a monolayer of cells lining the interior of the blood and lymphatic vessels
The cells were grown in Roswell Park Memorial Institute (RPMI) 1640 medium supplemented with 10% fetal bovine serum (FBS), 2 mM glutamine, 100 U/mL
The effect of insulin-like growth factor-1 (IGF-1) and/or CCL2 on the expression of their respective receptors was analyzed by flow cytometry. tEnd.1 cells expressed both receptors

Summary

Introduction

The endothelium is a monolayer of cells lining the interior of the blood and lymphatic vessels. This cellular layer is attached to the basal membrane and participates in the exchange of materials between blood and tissues. Endothelial cells release a multitude of biological mediators such as growth factors, vasoactive mediators, coagulation and fibrinolysis proteins, and immune factors. These cells are usually in the quiescent state, reflecting the stability and integrity of the vascular wall [2, 3]. During a series of physiological or pathological processes that involve angiogenesis, such as embryonic development, reproduction, wound repair, and tumor growth [4,5,6], the resting state changes and endothelial cells become elongated, highly motile, and sensitive to stimulation by growth factors [7]

Methods

Results

Conclusion