Objective  To explore the effect of esculetin (Esc) on the inflammatory injury of renal tubular epithelial cells induced by high glucose and its molecular mechanism.

  Methods  Renal tubular epithelial cells HK-2 were randomly divided into control (Con) group, high glucose (HG) group, low, medium and high concentration of Esc (HG+Esc-L, M, H) groups, HG+anti-miR-NC group, HG+anti-miR-486-5p group, HG+Esc+miR-NC group and HG+Esc+miR-486-5p group. Enzyme-linked immunosorbent assay (ELISA) was used to detect interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels. Flow cytometry was used to detect cell apoptosis rate. Real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was used to detect miR-486-5p expression level.

  Results  After treatment with low, medium and high concentrations of Esc, the levels of IL-6 and TNF-α and miR-486-5p expression in HK-2 cells induced by high glucose were gradually decreased, while the apoptosis rate was gradually decreased, and there were significant differences between groups (P < 0.05). After inhibiting the expression of miR-486-5p, the levels of IL-6, TNF-α and the apoptosis rate in HK-2 cells induced by high glucose were decreased (P < 0.05). After simultaneous treatments with over-expression of miR-486-5p and Esc, IL-6 and TNF-α levels and cell apoptosis rate were increased (P < 0.05).

  Conclusion  Esc inhibits the inflammatory injury of renal tubular epithelial cells induced by high glucose by down-regulating the expression of miR-486-5p.