The protective effect of glycyrrhizic acid on renal tubular epithelial cell injury induced by high glucose

Int J Mol Sci. 2014 Aug 26;15(9):15026-43. doi: 10.3390/ijms150915026.

Abstract

The aim of this study was to determine the beneficial effect of glycyrrhizic acid (GA) on type 2 diabetic nephropathy using renal tubular epithelial cell line (NRK-52E). The cells are divided into normal group (NG), high glucose group (HG), and treatment group (HG + GA). The methylthiazoletetrazolium (MTT) assay was used to detect the cell proliferation. Cell cycle analysis was performed using flow cytometry. Model driven architecture (MDA), reactive oxygen species (ROS) and superoxide dismutase (SOD) were also measured. Electron microscopy and histological were used to detect the changes in cell ultrastructure. The phosphorylation of AMP-activated protein kinase (AMPK), silent information regulator T1 (SIRT1), manganese-superoxide dismutase (Mn-SOD) and transforming growth factor-β1 (TGF-β1) were assessed by immunohistochemistry, immunofluorescence, and western blotting. Real-time fluorescent quantitative PCR (RT-qPCR) was used to measure Mn-SOD and PPARγ co-activator 1α (PGC-1a) mRNA. We find that high glucose increases NRK-52E cell proliferation and TGF-β1 expression, but decreases expression of AMPK, SIRT1 and Mn-SOD. These effects are significantly attenuated by GA. Our findings suggest that GA has protective effects against high glucose-induced cell proliferation and oxidative stress at least in part by increasing AMPK, SIRT1 and Mn-SOD expression in NRK-52E cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / genetics
  • AMP-Activated Protein Kinases / metabolism
  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Cycle
  • Cell Line
  • Cell Proliferation
  • Cell Survival
  • Diabetic Nephropathies / metabolism
  • Epithelial Cells / drug effects*
  • Epithelial Cells / metabolism
  • Epithelial Cells / physiology
  • Epithelial Cells / ultrastructure
  • Glucose / toxicity
  • Glycyrrhizic Acid / pharmacology*
  • Kidney Tubules / cytology
  • Oxidative Stress
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Reactive Oxygen Species / metabolism
  • Sirtuin 1 / genetics
  • Sirtuin 1 / metabolism
  • Superoxide Dismutase / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transforming Growth Factor beta1 / genetics
  • Transforming Growth Factor beta1 / metabolism

Substances

  • Anti-Inflammatory Agents
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Ppargc1a protein, rat
  • RNA, Messenger
  • Reactive Oxygen Species
  • Transcription Factors
  • Transforming Growth Factor beta1
  • Glycyrrhizic Acid
  • Superoxide Dismutase
  • AMP-Activated Protein Kinases
  • Sirt1 protein, rat
  • Sirtuin 1
  • Glucose