MicroRNA-34a promotes hypertension-induced vascular injury by targeting B-lymphocytoma-2

Abstract

Objective To investigate the level of microRNA (miRNA, miR)-34a in serum of hypertensive patients and its effect on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) by targeting B cell lymphoma/leukemia-2 (bcl-2), and clarify the underlying mechanism of hypertension-induced vascular injury. Methods Real-time quantitative polymerase chain reaction (qPCR) was used to detect the level of miR-34a in serum of 98 hypertensive patients and 65 healthy controls; the potential targets of miR-34a was predicted by TargetScan; the interaction between miR-34a and bcl-2 was measured by dual luciferase reporter assay, western blot and qPCR; the effect of miR-34a on proliferation and apoptosis of HUVECs was detected by methyl thiazol tetrazolium (MTT) and flow cytometry. Results The level of miR-34a in serum of 98 hypertensive patients (2.432±0.201) was significantly higher than that of 65 healthy controls (0.996±0.112, P 0.05). The protein and mRNA level of bcl-2 in HUVECs after overexpressing miR-34a (0.403±0.041, 0.206±0.018) decreased significantly than that in Blank group (1.000±0.098, 1.000±0.067) and miR-NC group (0.996±0.087, 1.012±0.049). The proliferation of HUVECs after overexpressing miR-34a (48 h: 0.269±0.021, 72 h: 0.324±0.028) decreased significantly than that of the Blank group (48 h: 0.324±0.025, 72 h: 0.458±0.044) and miR-NC group (48 h: 0.335±0.028, 72 h: 0.469±0.051, P<0.05), and apoptosis (23.54±2.65) was significantly higher than that of Blank (6.45±0.42) and miR-NC (7.32±0.54, P<0.05). Conclusion MiR-34a is overexpressed in serum of hypertensive patients. Overexpressing miR-34a can inhibit proliferation of HUVECs by targeting bcl-2 expression, which may be one of the potential mechanisms of vascular injury in hypertensive patients and provide experimental basis for using miR-34a as a new target to diagnose and treat hypertension in the future. Key words: MicroRNA-34a; B cell lymphoma/leukemia-2; Hypertension; Vascular injury