Expression of Signal Molecules in Culture of Human Endothelial Cells in Atherosclerosis and Restenosis

Inhibition of ERK or Akt ameliorates intimal hyperplasia via up-regulation of Cx37 and down-regulation of Cx43 in balloon injury rat model

Background

Connexins (Cxs) are reported to participate in atherosclerosis associated intimal hyperplasia (IH), while their function involved in the balloon injury (BI) induced IH and restenosis is less reported.

Methods

Forty-eight male Sprague-Dawley rats were randomly assigned to not injured (NI) group and BI group, which were further administrated with ERK-inhibitor U0216 and Akt-inhibitor MIK2206. Western blot and RT-PCR were utilized to detect the expression of Cx30, Cx37, Cx40, and Cx43 at 6 hours, 24 hours, 7 days, and 14 days post-surgery. H&E staining and related intima area, media area, and luminal area measurement were applied to indicate neointima formation and IH. ERK and Akt phosphorylation levels and proliferating cell nuclear antigen (PCNA) immunostaining were also detected.

Results

Among the four Cxs detected, Cx37 showed down-regulated, and Cx43 showed up-regulated temporal expression pattern in BI rats with confirmed neointima formation. Up-regulated p-ERK (P<0.01) and p-Akt (P<0.01) can be detected in BI rats compared with NI rats. Meanwhile, U0216 and MIK2206 can significantly reduce Cx43 expression and increase CX37 expression accompanied with reduced neointima formation and PCNA staining (P<0.05 or P<0.01) in BI rats.

Conclusions

ERK or Akt inhibition can alleviate BI-induced IH via up-regulation of Cx37 and down-regulation of Cx43.

MicroRNA-148a-3p promotes survival and migration of endothelial cells isolated from Apoe deficient mice through restricting circular RNA 0003575

The incidence of atherosclerosis is greatly increased, which becomes the leading cause for the death and disability worldwide. Endothelial cells dysfunction plays a substantial role in the pathogenesis of atherosclerosis. MicroRNA-148a-3p (miR-148a-3p) and circular RNA 0003575 (circ_0003575) modulated lipid metabolism and proliferative function of endothelial cells, respectively. However, the role of them in modulation of endothelial cell function and progression of atherosclerosis remains unknown. Endothelial cells were isolated from the aorta of Apoe^-/- mice. miR-148a-3p in atherosclerosis patients and healthy controls were measured by qRT-PCR. Overexpression and knockdown of miR-148a-3p in endothelial cells were established. The proliferation, migration and apoptosis of endothelial cells were measured by MTT, Transwell, and fluorescence microscope, respectively. Online software (miRWalk 2.0 and RegRNA2.0) and databases (miRWalk, miRanda, RNA22, and Targetscan) were used to predict potential target genes of miR-148a-3p and circ_0003575. The expression of target genes was detected through western blotting. The expression of miR-148a-3p was significantly upregulated in patients with atherosclerosis as relative to healthy people. Overexpression of miR-148a-3p exhibited stimulatory effects on endothelial cell proliferation and migration and inhibited programmed cell death. Six intersection target genes, c-MAF, FOXO4, FOXO3, MITF, ETV7, and CRX, were predicted between miR-148a-3p and circ_0003575. The opposite effects of circ_0003575 and miR-148a-3p on the expression of FOXO4 and FOXO3, which are essential for lipid metabolism. We demonstrate that miR-148a-3p suppresses FOXO4 and FOXO3 expression via interruption of circ_0003575 function, which in turn impairs the proliferative and migratory function of endothelial cells, eventually exacerbating the atherosclerosis.