Related Experiment Video
Updated: Jul 8, 2026
Real-time Monitoring of Mitochondrial Respiration in Cytokine-differentiated Human Primary T Cells
Published on: October 19, 2021
Mitochondrial oxygen consumption inhibition importance for TMT-dependent cell death in undifferentiated PC12 cells
Francesco Misiti1, Federica Orsini, M Elisabetta Clementi
1Department of Health and Motor Sciences, University of Cassino, Viale Bonomi, 03043 Cassino (FR), Italy. f.misiti@unicas.it <f.misiti@unicas.it>
Abstract:
The evolving role of mitochondria as a target for different death-inducing noxae prompted us to investigate trimethyltin (TMT)-dependent effects on mitochondrial functionality. For this purpose, we used a homogeneous cell culture model represented by undifferentiated PC12 cells. Mitochondria isolated from PC12 cells treated with TMT for 6, 12 and 24h, showed a time-dependent inhibition of ADP-stimulated oxygen consumption using succinate or glutamate/malate as substrate. Using a fluorescent assay, the effect of TMT on mitochondrial membrane potential (delta Psi) in PC12 cells was also determined. After 24h in culture, a strong loss of mitochondrial membrane potential (delta Psi) was observed in TMT-treated cells. Collapse of mitochondrial membrane potential correlated with an increased expression of bax/bcl-2 ratio, as evaluated by polymerase chain reaction. Western blotting and spectrophotometric analysis showed that cytochrome c release and activation of caspase 3 were concurrently induced. Our findings suggest that inhibition of mitochondrial respiration represents the early toxic event for cell death in PC12 due to trimethyltin.
Insights
Trimethyltin (TMT) exposure inhibits mitochondrial respiration and membrane potential in PC12 cells. This early mitochondrial dysfunction triggers cell death pathways, including caspase 3 activation.
Area of Science:
- Mitochondrial biology
- Cellular toxicology
- Neurotoxicology
Background:
- Mitochondria are crucial for cellular energy and survival.
- Various toxic agents target mitochondria, leading to cell death.
- Trimethyltin (TMT) is a known neurotoxicant, but its precise cellular mechanisms are under investigation.
Purpose of the Study:
- To investigate the effects of trimethyltin (TMT) on mitochondrial function in PC12 cells.
- To determine the role of mitochondrial dysfunction in TMT-induced cell death.
Main Methods:
- PC12 cells were treated with TMT for varying durations (6, 12, 24 hours).
- Mitochondrial respiration (oxygen consumption) was measured using succinate or glutamate/malate.
- Mitochondrial membrane potential (ΔΨ) was assessed using a fluorescent assay.
- Bax/Bcl-2 ratio, cytochrome c release, and caspase 3 activation were analyzed via PCR, Western blotting, and spectrophotometry.
Main Results:
- TMT treatment caused a time-dependent inhibition of mitochondrial respiration.
- A significant loss of mitochondrial membrane potential (ΔΨ) was observed after 24 hours of TMT exposure.
- TMT exposure led to an increased Bax/Bcl-2 ratio, cytochrome c release, and caspase 3 activation.
Conclusions:
- Inhibition of mitochondrial respiration is an early toxic event in TMT-induced cell death.
- Mitochondrial dysfunction plays a critical role in the mechanism of TMT toxicity.
- These findings highlight mitochondria as a key target for TMT neurotoxicity.
