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Updated: Aug 7, 2026

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
07:35

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess

Published on: June 1, 2022

Mitochondrial DNA mutations cause resistance to opening of the permeability transition pore

Justin L Mott1, Dekui Zhang, Shin-Wen Chang

  • 1Mayo Clinic College of Medicine, Guggenheim 17, Rochester, MN 55905, USA.

Biochimica Et Biophysica Acta
|July 11, 2006
PubMed

Insights

Mitochondrial DNA mutations in aging hearts trigger a protective response. This response inhibits the mitochondrial permeability transition pore, a key factor in cell death, suggesting a novel adaptive mechanism against heart disease.

Area of Science:

  • Mitochondrial biology
  • Cellular aging
  • Cardiovascular disease pathogenesis

Background:

  • Accumulation of mitochondrial DNA mutations is linked to age-related organ dysfunction and disease.
  • Accelerated mitochondrial mutagenesis in the mouse heart leads to pathology and myocyte apoptosis.
  • Mitochondrial permeability transition pore opening is a critical event initiating cell death, while its inhibition is protective.

Purpose of the Study:

  • To investigate functional alterations in mitochondrial cell death signaling pathways.
  • To determine the role of the mitochondrial permeability transition pore in the context of mitochondrial DNA mutations.
  • To elucidate the mechanism underlying pore inhibition in hearts with mitochondrial DNA mutations.

Main Methods:

  • Utilized transgenic mice with accumulating mitochondrial DNA mutations.
  • Assessed calcium-induced mitochondrial permeability transition pore opening.
  • Quantified Bcl-2 protein levels in mitochondrial membranes.
  • Treated isolated mitochondria with Bcl-2 antagonistic peptides (Bax, Bid BH3 domains).

Main Results:

  • Mitochondria from mice with mitochondrial DNA mutations exhibited inhibited calcium-induced pore opening.
  • Inhibited pore opening temporally coincided with disease progression.
  • Pore inhibition correlated with increased mitochondrial Bcl-2 protein.
  • Bcl-2 antagonistic peptides reversed the inhibition of pore opening.

Conclusions:

  • Mitochondrial DNA mutations induce a protective adaptive response in the heart.
  • This response involves Bcl-2-mediated inhibition of the mitochondrial permeability transition pore.
  • This adaptive mechanism may mitigate cell death and disease progression in the aging heart.

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