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Modeling Hypoxia/Reoxygenation Injury in Proximal Tubular Epithelial Cells
06:23

Modeling Hypoxia/Reoxygenation Injury in Proximal Tubular Epithelial Cells

Published on: November 21, 2025

High glucose-induced oxidative stress causes apoptosis in proximal tubular epithelial cells and is mediated by

David A Allen1, Steven Harwood, Mira Varagunam

  • 1Department of Experimental Medicine and Nephrology, William Harvey Research Institute, St Bartholomew's and Royal London School of Medicine and Dentistry, Queen Mary, University of London, UK. d.a.allen@qmul.ac.uk

FASEB Journal : Official Publication of the Federation of American Societies for Experimental Biology
|April 3, 2003
PubMed

Insights

High glucose in diabetic nephropathy triggers reactive oxygen species (ROS) and peroxynitrite (ONOO-) generation, leading to cell death. Inhibiting ONOO- or caspase-3 protects against this damage.

Area of Science:

  • Nephrology
  • Cell Biology
  • Biochemistry

Background:

  • Diabetic nephropathy is a major cause of kidney failure.
  • The exact mechanisms of high glucose-induced kidney injury remain unclear.
  • Proximal tubular epithelial cells (PTECs) are key targets in diabetic nephropathy.

Purpose of the Study:

  • To investigate the effects of high glucose on PTECs.
  • To identify the role of reactive oxygen species (ROS) and peroxynitrite (ONOO-) in high glucose-induced PTEC injury.
  • To explore potential therapeutic targets for early diabetic nephropathy.

Main Methods:

  • Utilized a proximal tubular epithelial cell (PTEC) line (LLC-PK1).
  • Measured reactive oxygen species (ROS) using fluorescent probes.
  • Assessed DNA fragmentation, caspase-3 activity, annexin-V staining, and XIAP expression.
  • Investigated the effects of ONOO- scavenger (ebselen) and caspase inhibitors.

Main Results:

  • High glucose (25 mM) increased ONOO- generation and nitrite concentrations in PTECs.
  • High glucose induced DNA fragmentation, caspase-3 activation, and apoptosis markers (annexin-V staining).
  • Ebselen and caspase inhibitors significantly reduced high glucose-induced apoptosis and DNA damage.

Conclusions:

  • High glucose induces PTEC apoptosis via ONOO- generation and caspase-mediated pathways.
  • ONOO- acts as a pro-apoptotic reactive oxygen species in early diabetic nephropathy.
  • Targeting ONOO- or caspase-3 may offer protective strategies against diabetic kidney disease.

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