Related Experiment Video
Updated: May 13, 2026
05:45
Isolation of Mitochondria for Mitochondrial Supercomplex Analysis from Small Tissue and Cell Culture Samples
Published on: May 3, 2024
The MICOS Complex Regulates Mitochondrial Structure and Oxidative Stress During Age-Dependent Structural Deficits in
Prasanna Katti1, Praveena Prasad2, Sepiso K Masenga3,4
1Department of Biology, Indian Institute of Science Education and Research (IISER), Tirupati, Andhra Pradesh, India.
Aging Cell
|May 12, 2026
Summary
Aging kidneys show significant mitochondrial structural changes, particularly fragmentation and impaired MICOS complexes. This dysfunction contributes to increased oxidative stress and metabolic alterations, potentially driving age-related kidney disease.
Area of Science:
- Cell Biology
- Gerontology
- Nephrology
Background:
- Kidney function declines with age, partly due to mitochondrial dysfunction.
- Mitochondrial ultrastructure, reactive oxygen species (ROS), metabolism, and lipid composition are altered during aging.
Purpose of the Study:
- To investigate age-related changes in mitochondrial ultrastructure within kidney tubular cells.
- To understand the role of the mitochondrial contact site and cristae organizing system (MICOS) complex in kidney aging.
Main Methods:
- Serial block face-scanning electron microscopy was used to visualize murine kidney samples from young (3 months) and old (2 years) mice.
- Manual segmentation with Amira software facilitated detailed ultrastructural analysis.
- ROS levels, metabolomics, and lipid homeostasis were assessed.
Main Results:
- Aged kidney mitochondria exhibited increased fragmentation and unique shapes compared to young mitochondria.
- The MICOS complex was found to be impaired in aged kidneys.
- MICOS complex disruption led to altered mitochondrial metabolism and elevated ROS levels.
Conclusions:
- Detrimental structural changes in aged kidney mitochondria, including MICOS complex impairment, suggest a mechanism for age-related kidney disease.
- Disruption of the MICOS complex may create a cycle of mitochondrial degradation and oxidative stress, impacting kidney health.
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