Role of oxidative stress and mitochondrial changes in cyanobacteria-induced apoptosis and hepatotoxicity

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Ratiometric Biosensors that Measure Mitochondrial Redox State and ATP in Living Yeast Cells
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Ratiometric Biosensors that Measure Mitochondrial Redox State and ATP in Living Yeast Cells

Published on: July 22, 2013

Wen-Xing Ding1, Choon Nam Ong

  • 1Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15213, USA. wed1@pitt.edu

FEMS Microbiology Letters
|March 20, 2003
PubMed

Insights

Cyanobacteria hepatotoxins, microcystins, induce cell death by damaging mitochondria and activating specific enzymes. Understanding these mechanisms is key to addressing microcystin toxicity.

Area of Science:

  • Hepatotoxicity
  • Cellular Biology
  • Toxicology

Background:

  • Microcystins are potent cyanobacterial hepatotoxins.
  • Mechanisms of microcystin-induced liver injury remain incompletely understood.

Purpose of the Study:

  • To investigate the cellular events and molecular pathways involved in microcystin-induced hepatotoxicity.
  • To elucidate the role of mitochondrial dysfunction and apoptosis in liver cells exposed to microcystins.

Main Methods:

  • Utilized cultured rat hepatocytes to study microcystin effects.
  • Assessed free radical formation, mitochondrial membrane potential, and mitochondrial permeability transition.
  • Investigated the activation of calpain and Ca(2+)/calmodulin-dependent protein kinase II.

Main Results:

  • Microcystin exposure induced free radical formation in hepatocytes.
  • Observed significant mitochondrial alterations, including loss of membrane potential and permeability transition.
  • Found evidence for the activation of calpain and Ca(2+)/calmodulin-dependent protein kinase II.

Conclusions:

  • Free radical generation and mitochondrial dysfunction are key events in microcystin hepatotoxicity.
  • Mitochondrial alterations are linked to apoptosis induction.
  • Calpain and Ca(2+)/calmodulin-dependent protein kinase II activation play critical roles in the apoptotic process.

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