[miR-34b-3p regulates the angiogenesis of senescent endothelial cell]

To investigate the effect of miR-34b-3p on the proliferation, migration and tube formation of senescent endothelial cell.

Primary human umbilical vein endothelial cells (HUVECs) were cultured in vitro, and population doubling levels (PDLs) were calculated by passage. The young endothelial cell was defined as PDL8. The senescent endothelial cell was defined as PDL44. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was applied to detect the expression of miR-34b-3p in PDL8 and PDL44 HUVECs. miR-34b-3p mimic and inhibitor were transfected into PDL8 and PDL44 HUVECs. Then, cell counting kit-8 (CCK-8), transwell and tube formation assays were used to determine the proliferation, migration and tube formation of HUVECs, respectively.

miR-34b-3p was significantly up-regulated approximately 4.3 times in PDL44 HUVECs than that in PDL44 HUVECs (t=-4.528, P<0.05). The proliferation, migration, total tube length and branch points of miR-34b-3p in PDL8 HUVECs group were significantly higher approximately 1.2 (0.67/0.57), 1.2 (106/86), 1.4 (10 605/7 735) and 1.3 (41/31) times than that in PDL44 HUVECs group, respectively (t=3.237, 3.564, 5.165, 3.487, P<0.05 or P<0.01). Overexpression of miR-34b-3p had significantly inhibited proliferation, migration, total tube length and branch points approximately 2.2 (0.67/0.30), 2.3 (106/46), 1.6 (10 605/6 652) and 1.9 (41/22) times in PDL8 HUVECs, respectively (F=145.898, 53.026, 41.997, 36.341, all P<0.01). Repression of miR-34b-3p had significantly increased proliferation, migration, total tube length and branch points approximately 1.4 (0.77/0.57), 2.3 (198/86), 1.7 (13 073/7 735) and 2.3 (71/31) times in PDL44 HUVECs, respectively (F=14.815, 42.970, 167.063, 258.340, all P<0.01).

The high expression of miR-34b-3p in senescent HUVECs could impair the proliferation, migration and tube formation of senescent endothelial cell.