The effect of microRNA-125 on the adhesion molecule expression of integrin beta2 and adhesive determination of endothelial cells isolated from human aorta to monocyte

Background: The immune-mediated responses in vascular cells may include the increased expression of endothelial adhesion molecules, leukocyte rolling and infiltration, cellular lipid dysregulation and vascular smooth muscle cells (VSMCs) differentiation. Investigating the cellular and molecular events involved in the rolling process is useful for treatment or prevention of the vessel stenosis especially in coronary arteries. MiRNAs are small and single-stranded noncoding RNAs with about 19-23 nucleotides. In this study, the role of microRNA-125 was predictably selected and experimentally investigated on the changes of expression level of adhesion molecule in endothelial cells isolated from human aorta and on the monocyte cells isolated from whole blood human with endothelial cells adhesion. The aim of this study was to determine the effect of miRNA-125 repression on cell adhesion in leukocyte rolling process to reduce or suppress artery stenosis in susceptible individuals. Methods: This experimental study was performed in Cellular-Molecular Research Center of Iran University of Medical Sciences, Tehran, Iran from July to December 2017. Normal aortic samples were prepared from subjects with brain death in Masih Daneshvari Hospital and under strictly sterile conditions, it was transferred as soon as possible. The endothelial cells were isolated from aorta of subjects with brain death using collagenase. The monocytes were isolated from whole blood. The microRNA-125 was transfected into ECs with use of polyethyleneimine (PEI). The expression level of adhesion molecule and monocyte recruitment were identified by quantitative reverse transcription polymerase chain reaction (qRT-PCR) technique and CytoSelect™ leukocyte-endothelium adhesion assay kit (Cell Biolabs, San Diego, CA, USA), respectively. Results: The results showed the microRNA-125 suppresses significantly integrin beta 2 (ITGB2) expression level (P=0.008). In addition, the monocyte-EC adhesion was shown in the aortic miRNA-treated endothelial cells. The adhesive rate between cells reduced significantly with microRNA-125 as compared with miR-synthetic (P=0.02). Thereby, there were the associations between the ITGB2 and miR-125a. Downregulation of ITGB2 may be reduced the adhesion of endothelial cells and moderating the process rolling. Conclusion: This study suggested that the suppression of leukocyte rolling process might be more due to the function of ITGB2. However, the functional effects of this miRNA should be directly investigated on the studied gene.