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Isolation of Primary Human Proximal Tubule Epithelial Cells and Their Use in Creating a Microphysiological Model of the Renal Proximal Tubule
07:06

Isolation of Primary Human Proximal Tubule Epithelial Cells and Their Use in Creating a Microphysiological Model of the Renal Proximal Tubule

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The nephrotoxin ochratoxin A induces apoptosis in cultured human proximal tubule cells

G Schwerdt1, R Freudinger, S Mildenberger

  • 1Physiologisches Institut, Universität Würzburg, Germany. gerald.schwerdt@mail.uni-wuerzburg.de

Cell Biology and Toxicology
|May 16, 2000
PubMed

Insights

The mycotoxin ochratoxin A (OTA) triggers apoptosis in kidney cells by activating caspase 3. Even low dietary exposure levels of OTA can initiate this cell death pathway, impacting renal epithelial cells.

Area of Science:

  • Toxicology
  • Cell Biology
  • Nephrology

Background:

  • Ochratoxin A (OTA) is a nephrotoxic mycotoxin found in food.
  • Understanding OTA's cellular mechanisms is crucial for assessing health risks.

Purpose of the Study:

  • To investigate the apoptotic potential of ochratoxin A (OTA) in human proximal tubule cells.
  • To determine the effects of OTA on caspase 3 activation, chromatin condensation, and DNA fragmentation.

Main Methods:

  • Exposure of human proximal tubule-derived cells (IHKE cells) to varying OTA concentrations (2-100 nmol/L).
  • Assay of caspase 3 activation, chromatin condensation, and DNA fragmentation.
  • Testing effects of radical scavengers and calcium chelators.

Main Results:

  • OTA induced time- and concentration-dependent caspase 3 activation, with effects seen at 5 nmol/L after 7 days.
  • Significant caspase 3 activation occurred at 10 nmol/L OTA after 24-72 hours.
  • DNA fragmentation and chromatin condensation were observed at OTA concentrations of 30 nmol/L and above.

Conclusions:

  • Low concentrations of OTA can activate caspase 3, leading to apoptosis in human proximal tubule cells.
  • OTA induces apoptosis in various renal epithelial cell lines.
  • The findings highlight the apoptotic risk of dietary ochratoxin A exposure.

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