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Updated: Jul 15, 2026
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Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes
Published on: January 7, 2013
Mitochondria a key role in microcystin-LR kidney intoxication
R La-Salete1, M M Oliveira, C A Palmeira
1Chemistry Department, CECAV, University of Trás-os-Montes and Alto Douro, 5001-801 Vila Real, Portugal.
Journal of Applied Toxicology : JAT
|April 28, 2007
Summary
Microcystin-LR, a cyanobacterial toxin, impairs kidney function by disrupting mitochondrial respiration and causing cell damage. This bioenergetic disruption is sufficient to explain the observed renal injury from microcystin exposure.
Area of Science:
- Toxicology
- Biochemistry
- Cell Biology
Background:
- Microcystins (MCs) are cyclic heptapeptides from cyanobacteria, linked to human and livestock mortality.
- Microcystin-LR (MC-LR) is suspected to directly impact kidney physiology, affecting various renal parameters.
Purpose of the Study:
- To investigate the specific effects of MC-LR on mitochondrial oxidative phosphorylation in isolated rat kidney mitochondria.
- To elucidate the mechanism by which MC-LR induces renal injury at the mitochondrial level.
Main Methods:
- Isolated rat kidney mitochondria were used to assess oxidative phosphorylation.
- Measurements included state 3 respiration, FCCP-uncoupled respiration, and transmembrane potential.
- Mitochondrial swelling and permeability transition pore (MPTP) opening were evaluated.
Main Results:
- MC-LR inhibited state 3 and FCCP-uncoupled respiration, decreasing mitochondrial transmembrane potential.
- The toxin's effect on transmembrane potential was due to inhibition of redox complexes, not increased proton permeability.
- MC-LR induced MPTP opening and mitochondrial swelling, dependent on reactive oxygen species, calcium, and ruthenium red.
Conclusions:
- MC-LR disrupts mitochondrial bioenergetics by inhibiting redox complexes and inducing MPTP opening.
- The observed bioenergetic dysfunction and subsequent cellular events are sufficient to explain MC-LR-induced renal injury.
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