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Updated: Aug 29, 2025

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

Published on: June 1, 2022

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Non-conventional mitochondrial permeability transition: Its regulation by mitochondrial dynamics

Yisang Yoon1, Hakjoo Lee1, Marilen Federico2

  • 1Department of Physiology, Medical College of Georgia, Augusta University, Augusta 30912, GA, USA.

Biochimica Et Biophysica Acta. Bioenergetics
|September 5, 2022
PubMed

Insights

Mitochondrial permeability transition (MPT) involves a pore (PTP) opening, causing cell injury. A novel, CsA-insensitive MPT regulated by mitochondrial dynamics may offer therapeutic benefits.

Area of Science:

  • Mitochondrial biology
  • Cellular physiology
  • Biochemistry

Background:

  • Mitochondrial permeability transition (MPT) is a critical process involving the opening of the permeability transition pore (PTP) in the inner mitochondrial membrane (IMM).
  • PTP opening leads to mitochondrial dysfunction and cell injury, and its molecular identity remains debated, though cyclophilin D is a known regulator.
  • Mitochondrial dynamics, encompassing fission and fusion, influence mitochondrial structure and function, and are implicated in regulating MPT.

Purpose of the Study:

  • To investigate the role of mitochondrial dynamics in regulating MPT.
  • To explore the existence and characteristics of a cyclosporine A (CsA)-insensitive MPT.
  • To assess the potential protective role and therapeutic value of this non-conventional MPT.

Main Methods:

  • Electrophysiological recordings to study PTP activity.
  • Investigating the impact of mitochondrial dynamics regulators on MPT.
  • Utilizing CsA as a control to differentiate between conventional and non-conventional MPT.

Main Results:

  • Evidence suggests a transient MPT distinct from the conventional CsA-sensitive PTP.
  • This non-conventional MPT is modulated by mitochondrial fission and fusion processes.
  • The non-conventional MPT may act as a protective mechanism against excessive PTP opening.

Conclusions:

  • Mitochondrial dynamics play a significant role in regulating a novel form of MPT.
  • This CsA-insensitive MPT pathway could have therapeutic implications for diseases associated with mitochondrial dysfunction.
  • Further research into non-conventional MPT may uncover new therapeutic strategies.
Keywords:
Mitochondrial dynamicsMitochondrial permeability transitionNon-conventional mitochondrial permeability transitionPermeability transition pore

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