Structural changes of mitochondria during free radical-induced apoptosis

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Updated: Oct 15, 2026

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue
09:27

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue

Published on: March 23, 2015

T Wakabayashi1, J H Spodnik

  • 1Department of Cell Biology and Molecular Pathology, Nagoya University School of Medicine, Japan. twakaba@tsuru.med.nagoya-u.ac.jp

Folia Morphologica
|June 22, 2000
PubMed

Insights

Mitochondria, once thought to remain intact during apoptosis, are now known to undergo crucial swelling via megachannel opening. This process, often triggered by free radicals, involves significant mitochondrial structural changes.

Area of Science:

  • Cell Biology
  • Biochemistry

Background:

  • Early apoptosis research focused on nuclear changes and intact organelles.
  • Mitochondria were initially considered unaffected during programmed cell death.

Purpose of the Study:

  • To review the structural role of mitochondria in apoptosis.
  • To highlight the importance of mitochondrial membrane megachannel opening.

Main Methods:

  • Review of accumulated experimental data.
  • Application of fluorescent dyes and flow cytometry for organelle analysis.

Main Results:

  • Mitochondrial membrane megachannel opening, leading to swelling, is a critical apoptotic event.
  • Calcium ions (Ca2+) and free radicals induce mitochondrial swelling.
  • Free radical-induced formation of megamitochondria is observed.

Conclusions:

  • Mitochondrial structural dynamics, particularly swelling, are central to apoptosis.
  • Mitochondria play a dynamic and crucial role in programmed cell death pathways.

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