MicroRNA-18a Improves Human Cerebral Arteriovenous Malformation Endothelial Cell Function

Abstract

Background and Purpose-Cerebral arteriovenous malformation (AVM) is a vascular disease that disrupts normal blood flow and leads to serious neurological impairment or death. Aberrant functions of AVM-derived brain endothelial cells (AVM-BECs) are a disease hallmark. Our aim was to use microRNA-18a (miR-18a) as a therapeutic agent to improve AVM-BEC function. Methods-Human AVM-BECs were tested for growth factor production and proliferation under different shear flow conditions and evaluated for tubule formation. Thrombospondin-1, inhibitor of DNA-binding protein 1, and vascular endothelial growth factor (VEGF) isotype mRNA levels were quantified by quantitative real-time polymerase chain reaction. Thrombospondin-1, VEGF-A, and VEGF-D protein expression was measured using enzyme-linked immunosorbent assay. Proliferation and tubule formation were evaluated using bromodeoxyuridine incorporation and growth factor-reduced Matrigel assays, respectively. Results-miR-18a increased thrombospondin-1 production but decreased inhibitor of DNA-binding protein 1, a transcriptional repressor of thrombospondin-1. miR-18a reduced VEGF-A and VEGF-D levels, both overexpressed in untreated AVM-BECs. This is the first study reporting VEGF-D overexpression in AVM. These effects were most prominent under arterial shear flow conditions. miR-18a also reduced AVM-BEC proliferation, improved tubule formation, and was effectively internalized by AVM-BECs in the absence of extraneous transfection reagents. Conclusions-We

MiR-18a increased the permeability of BTB via RUNX1 mediated down-regulation of ZO-1, occludin and claudin-5

“…MiR-18a-5p induced the differentiation of vascular smooth muscle cells (VSMC) by targeting syndecan4 [32]. MiR-18a improves human cerebral arteriovenous malformation endothelial cell function [15]. Overexpression of miR-18a significantly inhibited 3-dimensional spheroid sprouting in vitro, whereas inhibition of miR-18a augmented endothelial cell sprout formation [12].…”

“…Overexpression of miR-18a caused a marked reduction in tumor angiogenesis assessed by CD31-stained microvessel count [14]. And miR-18a improves human cerebral arteriovenous malformation endothelial cell function [15]. However, whether miR-18a is involved in regulating glioma vascular endothelial cells (GECs) function and further modulating the permeability of BTB still remain unclear.…”

Molecular and cellular biology of cerebral arteriovenous malformations: a review of current concepts and future trends in treatment

“…Moreover, miR-18a successfully penetrates target cells without additional reagents, allowing for intravenous or endovascular infusion, making it a promising therapeutic option. 11,58 The effect of radiation on the molecular process of AVM pathophysiology is of particular interest given its known ability, delivered as SRS, to drive endothelial proliferation and ultimately AVM obliteration. 43 Radiation elevates proapoptotic factors, such as p53, p21Waf-1, and mdm-2 mRNA.…”

Argonaute‐2 Promotes miR‐18a Entry in Human Brain Endothelial Cells

“…Namely, AVM‐BEC proliferate more rapidly, migrate faster, and produce aberrant vessel‐like structures as compared with normal vasculature. We have also shown that AVM‐BEC express low levels of a key regulator of angiogenesis, thrombospondin‐1 (TSP‐1), and the aberrant phenotype of these cells can be normalized by restoring TSP‐1 levels . We have recently shown that these abnormal features are ameliorated with microRNA‐18a (miR‐18a) treatment.…”

“…In our study, we showed that miR‐18a inhibited TSP‐1 transcriptional repressor, Inhibitor of DNA‐binding protein‐1 (Id‐1), leading to increased TSP‐1 levels and decreased vascular endothelial growth factor (VEGF)‐A and VEGF‐D secretion. miR‐18a also regulated cell proliferation and improved tubule formation efficiency . Importantly, these effects were obtained with miRNA alone (naked delivery), in the absence of traditional transfection reagents, like lipofectamine, which cannot be used in vivo due to induced toxicity.…”