Related Experiment Video

Updated: Jun 6, 2025

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

2.2K

Inside-out submitochondrial particles affect the mitochondrial permeability transition pore opening under conditions

Cristina Algieri1, Antonia Cugliari1, Patrycja Anna Glogowski1

  • 1Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy.

Biochimica Et Biophysica Acta. Bioenergetics
|November 30, 2024
PubMed

Insights

Inside-out submitochondrial particles (IO-SMPs) protect swine heart mitochondria from damage by preventing mitochondrial permeability transition pore (mPTP) opening. This effect stems from structural modifications rather than altered enzyme activity, suggesting therapeutic potential.

Area of Science:

  • Mitochondrial biochemistry
  • Cardiovascular research

Background:

  • Mitochondrial permeability transition pore (mPTP) opening is implicated in mitochondrial damage and cardiovascular diseases.
  • Mitochondria isolated from swine hearts 3 hours post-explantation exhibit damage, serving as a model for studying protective interventions.

Purpose of the Study:

  • To investigate the protective effect of inside-out submitochondrial particles (IO-SMPs) against mPTP opening in damaged mitochondria.
  • To elucidate the mechanism underlying the protective action of IO-SMPs.

Main Methods:

  • Isolation of mitochondria from swine hearts 3 hours after explantation to model mitochondrial damage.
  • Assessment of mPTP opening in the presence and absence of IO-SMPs.
  • Evaluation of oxidative phosphorylation and F1FO-ATPase activity to determine the impact on enzymatic complexes.

Main Results:

  • IO-SMPs demonstrated a significant protective effect against mPTP opening in damaged swine heart mitochondria.
  • The protective effect was not mediated by functional modulation of enzymatic complexes involved in mPTP formation, as oxidative phosphorylation and F1FO-ATPase activity remained unaffected.
  • Evidence suggests that IO-SMPs induce mPTP desensitization through structural modifications within the mitochondria.

Conclusions:

  • IO-SMPs can prevent mPTP opening in damaged mitochondria, likely by altering mitochondrial structure and modulating F1FO-ATPase functionality.
  • These findings provide a basis for exploring IO-SMPs as a therapeutic strategy for cardiovascular conditions associated with mPTP opening.
Keywords:
F(1)F(O)-ATPaseInside-out submitochondrial particlesMitochondrial dysfunctionMitochondrial permeability transition pore

More Related Videos

Multi-parameter Measurement of the Permeability Transition Pore Opening in Isolated Mouse Heart Mitochondria13:42

Multi-parameter Measurement of the Permeability Transition Pore Opening in Isolated Mouse Heart Mitochondria

Published on: September 7, 2012

21.4K
Simultaneous Measurement of Mitochondrial Calcium and Mitochondrial Membrane Potential in Live Cells by Fluorescent Microscopy08:43

Simultaneous Measurement of Mitochondrial Calcium and Mitochondrial Membrane Potential in Live Cells by Fluorescent Microscopy

Published on: January 24, 2017

18.9K

Related Concept Videos

The Inner Mitochondrial Membrane01:28

The Inner Mitochondrial Membrane

The inner mitochondrial membrane is the primary site of ATP synthesis. The inner membrane domain that forms a smooth layer adjacent to the outer membrane is called the inner boundary membrane. This domain contains membrane transporters that drive metabolites in and out of the mitochondria.  In contrast, the inner membrane network that invaginates into the matrix space is called the cristae membrane. This domain accounts for principle mitochondrial function as it accommodates the protein...
3.3K
Mitochondrial Membranes01:45

Mitochondrial Membranes

A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...
8.7K
Translocation of Proteins into the Mitochondria01:19

Translocation of Proteins into the Mitochondria

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
3.0K
Porin Insertion in the Outer Mitochondrial Membrane01:12

Porin Insertion in the Outer Mitochondrial Membrane

Porins are beta-barrel proteins translocated to the mitochondrial outer membrane through the TOM complex into the intermembrane space. Porin precursors bind TIM chaperones within the intermembrane space and are guided to the Sorting and Assembly Machinery complex or SAM complex on the outer mitochondrial membrane.
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
2.8K
Structure of Porins01:21

Structure of Porins

Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a  motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel...
2.9K
Mitochondrial Precursor Proteins01:39

Mitochondrial Precursor Proteins

Mitochondrial precursors are partially unfolded or loosely folded polypeptide chains. Newly synthesized precursors are inhibited from spontaneously folding into their native conformation by the cytosolic chaperones, heat shock proteins 70 (Hsp70), and mitochondrial import stimulation factors (MSFs). Precursors bound to MSFs are guided to the TOM70-TOM37 receptors, while precursors bound to Hsp70  chaperones are targetted to TOM20-TOM22 receptor complexes.
Most of the mitochondrial...
2.5K