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Updated: Jul 26, 2025
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Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue
Published on: March 23, 2015
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Mitochondrial outer membrane permeabilization and inner membrane permeabilization in regulating apoptosis and
Hong Qi1, Yu-Song Yin2, Zhi-Yong Yin3
1Complex Systems Research Center, Shanxi University, Taiyuan, China; Wenzhou Key Laboratory of Biophysics, Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, China.
Journal of Theoretical Biology
|June 16, 2023
Summary
This study models the link between apoptosis and inflammation via mitochondrial membrane permeabilization. Bax aggregation kinetics and caspase 3 inhibition determine cell fate, offering a framework for understanding cell death and immune responses.
Area of Science:
- Cell Biology
- Systems Biology
- Immunology
Background:
- Growing evidence highlights the interplay between apoptosis and inflammation.
- The precise mechanisms governing mitochondrial membrane permeabilization in this crosstalk remain unclear.
Purpose of the Study:
- To develop a mathematical model elucidating the dynamic link between apoptosis and inflammation.
- To investigate the role of mitochondrial membrane permeabilization in controlling cell fate decisions.
Main Methods:
- Construction of a four-module mathematical model.
- Bifurcation analysis to identify sources of bistability.
- Time series analysis to quantify key event timings.
Main Results:
- Bistability in the system arises from Bcl-2 family member interactions.
- A ~30-minute time difference exists between cytochrome c and mtDNA release.
- Bax aggregation kinetics dictate whether cells undergo apoptosis or inflammation.
- Modulating caspase 3's inhibition of IFN-β production permits simultaneous apoptosis and inflammation.
Conclusions:
- The model provides a theoretical framework for understanding mitochondrial membrane permeabilization's role in cell fate.
- Bax aggregation emerges as a critical determinant in switching between apoptosis and inflammation.
- The findings suggest potential therapeutic targets for diseases involving dysregulated cell death and inflammation.
Keywords:
ApoptosisDynamic mechanismInflammationMitochondrial inner membrane permeabilizationMitochondrial outer membrane permeabilizationMore Related Videos
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