Biological effects of micro RNA-155 in cardiac myocyte apoptosis / 中国医师进修杂志

ABSTRACT

Objective To analyze the biological effects of miRNA-155 in the cardiac myocyte apoptosis. Methods The mouse-derived macrophage cell line RAW264.7 was treated by different concentration or different stage of oxidized low density lipoprotein (ox-LDL), and transfected by miR-155 mimic (M group), miR-155 mimics-NC (M-NC group), miR-155 inhibitor (I group) or miR-155 inhibitor-NC (I-NC group), respectively. The cell viability was measured by CCK-8 assay, cell apopotosis was measured by TUNEL and flow cytometry. Results The ox-LDL induced cell viability of Raw264.7 cells decreased and the expression of miR-155 increased in dose and time dependent manner, after treatment with different concentration of ox-LDL (10, 20, 40, 80, 160 mg/L) or 80 mg/L of ox-LDL with different stage (6, 12, 24, 48, 72 h). The expression of miR-155 increased significantly. Raw264.7 cell viability decreased significantly, compared to that of the blank control. The difference between two groups had statistical significance (P＜0.05). The cell viability in M group was significantly higher than that in M-NC group, in I group was significantly higher than that in I-NC group, and the difference between two groups was statistical significance (P＜0.05). Compared to that in the M-NC group, the cell apoptosis rate in M group was significantly increased (P＜0.05), compared to that in the I-NC group, the cell apoptosis rate in I group were significantly decreased (P＜0.05). Conclusions miR-155 can enhance the Raw264.7 cell apoptosis induced by ox-LDL.