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Updated: Jun 23, 2025
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Author Spotlight: Unveiling Oxidative Phosphorylation System Dynamics and Mitochondrial Roles in Health and Disease
Published on: May 3, 2024
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The MICOS Complex Regulates Mitochondrial Structure and Oxidative Stress During Age-Dependent Structural Deficits in
Zer Vue1, Praveena Prasad2, Han Le3,4
1Department of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, AP, 517619, India.
Biorxiv : the Preprint Server for Biology
|June 25, 2024
Summary
Aging kidneys show mitochondrial fragmentation and impaired MICOS complex function, leading to oxidative stress and potential kidney disease mechanisms. This research highlights structural changes impacting kidney health over time.
Area of Science:
- Nephrology
- Cell Biology
- Aging Research
Background:
- Kidney function relies on cellular energy production by mitochondria, which declines with age.
- Mitochondrial dysfunction and structural changes, including cristae alterations, are hallmarks of aging.
- Age-related kidney decline may stem from mitochondrial ultrastructural changes, oxidative stress, and metabolic shifts.
Purpose of the Study:
- To investigate age-related changes in kidney tubular cell mitochondrial ultrastructure using 3D morphological analysis.
- To understand the impact of aging on mitochondrial morphology, reactive oxygen species (ROS), and lipid homeostasis in kidney cells.
Main Methods:
- Serial block-facing scanning electron microscopy (SBF-SEM) was employed to visualize murine kidney samples.
- Amira software was used for manual segmentation and 3D reconstruction of mitochondria at different ages (3 months and 2 years).
Main Results:
- Mitochondria in 2-year-old kidneys were more fragmented and exhibited unique shapes compared to 3-month-old kidneys.
- Aging led to impaired mitochondrial contact site and cristae organizing system (MICOS) complex function, affecting calcium handling and increasing oxidative stress.
- Significant detrimental structural changes were observed in aged kidney tubule mitochondria.
Conclusions:
- Age-related kidney disease may be linked to structural mitochondrial damage and impaired MICOS complex function.
- Disruption of the MICOS complex exacerbates mitochondrial dysfunction and oxidative stress, creating a detrimental cycle impacting kidney health.
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