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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
Summary
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 poreMore Related Videos
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