ABSTRACT
Objective To investigate the effect and potential mechanism of microRNA (miRNA)-377 on high glucose-induced proliferation and inflammation in human mesangial cells.Methods Cells were randomly divided into six groups:control group (5.5 mmol/L glucose),high glucose group (30.0 mmol/L glucose),negtive miRNA inhibitor transfection+high glucose group,negtive miRNA mimic transfection+high glucose group,miRNA-377 inhibitor transfection+high glucose group (miR-377i+high glucose group),miRNA-377 mimic transfection+high glucose group (miR-377m+high glucose group),miRNA-377 expression was detected by real-time PCR.Cell proliferation and cell cycle were detected by BrdU assay and flow cytometry,respectively.The release of tumor necrosis factor-α (TNF-α),interleukin (IL)-18,IL-6 and macrophages chemotaxis protein-1 (MCP-1) were evaluated by ELISA.The activations of NF-κB pathway,including the expressions of phosporylated (p)-IκBα,p-P65 and nuclear P65,were measured by Western blotting.Results Compared with those in control group,in high glucose group cell viability,miRNA-377 expression and cell proliferation rate increased (all P ＜ 0.05),proportions of S phase cell and G2/M phase cell in cell cycle increased (all P ＜ 0.05),the levels of TNF-o,IL-18,IL-6 and MCP-1 were higher (all P ＜ 0.05),as well as the expressions of p-IKBα/IκBα,p-P65/P65 and nuclear P65 were increased (all P ＜ 0.05).Compared with high glucose group,cell proliferation rate was restrained (P ＜ 0.05),proportions of S phase cell and G2/M phase cell in cell cycle was descreased (all P ＜ 0.05),the levels of TNF-α,IL-18,IL-6 and MCP-1 were lower (all P ＜ 0.05),as well as the expressions of p-IκBα/IκBα,p-P65/P65 and nuclear P65 were reduced (all P ＜ 0.05) in miR-377i+high glucose group.However,miR-377m+high glucose group presented opposite results (all P ＜ 0.05).Conclusions miRNA-377 knockdown can partially suppress high glucose-induced human mesangial cell proliferation and cell cycle transition,and restrain inflammatory molecules release.Its mechanism may be related to the inhibition of NF-κB pathway.