Exp Physiol. 2021 Apr 29.
NEW FINDINGS: What is the central question of this study? Diabetic nephropathy (DN) is a severe diabetic complication correlated to higher mortality rate in diabetic patients. Renal tubular injury participates in the pathogenesis of DN. We aimed to uncover the biological function of NEAT1/miR-150-5p/Drp1 axis in an in vitro model of DN and elaborate the potential mechanisms. What is the main finding and its importance? NEAT1 facilitated HG-induced damage in HK-2 cells by reducing mitophagy via miR-150-5p/Drp1 axis, which sheds light on DN pathogenesis and discovers a potential treatment for DN.ABSTRACT: Diabetic nephropathy (DN) is a severe diabetic complication with a high mortality rate in diabetic patients. Renal tubular injury is involved in the pathogenesis of DN. In this study, we aimed to uncover the regulatory roles of NEAT1/miR-150-5p/Drp1 axis in an in vitro model of DN and its possible mechanisms. HG-challenged HK-2 cells were used as an in vitro DN model. NEAT1, miR-150-5p, and Drp1 levels were assessed by RT-qPCR. Cell viability was determined by MTT assay. MitoSOX red and JC-1 were used to evaluate intra-cellular ROS production and mitochondrial membrane potential (MMP), respectively. LDH release and SOD activity were assessed by commercial kits. The protein levels of Drp1, p62, Beclin-1 and BNIP3 were determined by Western blotting. The interaction between NEAT1 (Drp1) and miR-150-5p was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our results showed that NEAT1 and Drp1 levels were up-regulated, while miR-150-5p level was down-regulated in HK-2 cells in response to HG. Knockdown of NEAT1 or Drp1 inhibited excessive ROS production and LDH release, increased cell viability, MMP, SOD activity and enhanced mitophagy in HG-challenged HK-2 cells. However, inhibition of miR-150-5p resulted in the opposite results. Mechanistically, NEAT1 sponged miR-150-5p to increase Drp1 level. Moreover, silencing of NEAT1 or Drp1 could counteract miR-150-5p inhibition-induced deleterious effects. Collectively, our findings indicate that NEAT1 facilitates HG-induced damage in HK-2 cells by suppressing mitophagy via miR-150-5p/Drp1 axis, which sheds light on a novel mechanism of DN. This article is protected by copyright. All rights reserved.
Keywords: Drp1; NEAT1; diabetic nephropathy; miR-150-5p; mitophagy; renal tubular injury