Abstract: Objective The study is to investigate the rolel of miR-328 in endothelial mesenchymal transition (EndMT) induced by high glucose in human umbilical vein endothelial cells (HUVECs) and its signaling mechanism. Methods HUVECs were cultured in high glucose environment to induce EndMT; The recombinant lentiviruses were produced by miR-328 and antagomiR- 328 transfection of HUVECs. The experiment was divided into seven groups: normal glucose; mannitol group; high glucose; miR-328; miR-328 virus negative control; high glucose + U0126; miR-328 + U0126. Double immunofluorescent staining was used to determine expression of EndMT markers; Changes in miR-328 expression is examined by RT-qPCR; The expressions of typeⅠⅢ collagen, p-MEK1/2 and p-ERK1/2 are examined by Western blot. Results 1). Immunofluorescent staining showed that the HUVECs showed positive staining for CD31 and α-SMA in high glucose group. 2). Compared with the control group, the expression of miR-328 was up-regulated(p <0.05) in HUVECs treated by high glucose or miR-328. Compared with high glucose group or miR-328 group, miR-328 expression were less pronounced after treatment with U0126. 3). The expressions of typeⅠ/Ⅲ collagen increased in HUVECs treated by high glucose or miR-328 when compared with control group (p <0.05). Compared with high glucose group or miR-328 group, typeⅠ/Ⅲ collagen expressions were less pronounced after treatment with U0126. 4). The expressions of p-MEK1 / 2 and p-ERK1 / 2 were increased in HUVECs treated by high glucose or miR-328 in comparison to the control group (p <0.05); a lower expression of p-MEK1 / 2 and p-ERK1 / 2 were observed in U0126 group than in high glucose group or miR-328 group. Conclusion The phenomenon of EndMT in HUVECs is induced by high glucose, and the expression of miR-328 is increased at the same time; overexpression of miR-328 induced EndMT in HUVECs; miR-328 induced EndMT is related with MEK1 / 2-ERK1 / 2 signaling pathway.

Key words: HUVEC, miR-328, endothelial–mesenchymaltransition(EndMT), MEK1/2-ERK1/2