MicroRNA-148b influences high glucose-induced endoplasmic reticulum stress in rat mesangial cell by targeting AMPKα1 / 中华肾脏病杂志

ABSTRACT

Objective To observe the expression of microRNA-148b (miR-148b) induced by high glucose in rat mesangial cells,and to explore its effect on its target gene AMP-activated protein kinase α1 (AMPKα1) and extracellular matrix excretion.Methods Rat mesangial cells were divided ino 3 groupsnormal glucose (NG,5.5 mmol/L glucose) group,hypertonic (MA,5.5 mmol/L glucose+19.5 mmol/L mannitol) group and high-glucose (HG,25.0 mmol/L glucose) group.MiR-148b expression was detected by real time PCR.Then miR-148b inhibitor was transfected to rat mesangial cells.Their protein expressions of AMPKα1,glucose regulated protein 78 (GRP78),C/EBP homologous protein (CHOP),fibronectin (FN) and collagen Ⅳ were detected by Western blotting.The expression of AMPKα1 mRNA was detected by real time PCR.The expression of collagen Ⅳ was also detected by immunofluorescence.Results Compared with NG group,HG group showed up-regulated miR-148bexpression,down-regulated AMPKαl mRNA and protein expressions,and up-regulated CHOP,GRP78,collagen Ⅳ and FN expressions (all P ＜ 0.05).HG-induced mesangial cells with miR-148binhibitor had up-regulated AMPKα1 mRNA and protein expressions,and down-regulated CHOP,GRP78,collagen Ⅳ,FN expressions as compared with HG-induced cells without miR-148b inhibitor (all P ＜ 0.05).Conclusions HG can up-regulate miR-148b expression and down-regulate AMPKα1 expression in rat mesangial cells,then activate endoplasmic reticulum stress to induce extracellular matrix excretion.MiR-148b inhibitor up-regulates AMPKα1 expression,inhibits endoplasmic reticulum stress and reduces extracellular matrix excretion.