Pleiotropic effects of mitochondria in aging
Tanes Lima1, Terytty Yang Li1, Adrienne Mottis1
1Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Nature Aging
|April 28, 2023
Summary
Aging involves declining mitochondrial function and stress resilience. This review explores how mitochondrial stress pathways, crucial for cellular health, become defective with age, contributing to disease.
Area of Science:
- Gerontology and cellular biology
- Mitochondrial biology and aging research
Background:
- Aging is characterized by reduced mitochondrial activity and impaired stress resilience.
- Mitochondrial stress response pathways are critical for maintaining cellular and systemic homeostasis.
- Defects in these pathways are increasingly linked to aging and age-related diseases.
Purpose of the Study:
- To review the pleiotropic effects of mitochondrial stress pathways during aging.
- To highlight the contribution of defective adaptive pathways to aging and age-related diseases.
- To discuss the interconnectedness of mitochondrial processes in aging.
Main Methods:
- Literature review of recent evidence on mitochondrial stress pathways in aging.
- Analysis of signaling pathways including mitochondrial unfolded protein response, membrane dynamics, and mitophagy.
- Examination of how pathway failures impact heteroplasmy and metabolite regulation.
Main Results:
- Mitochondrial stress pathways exhibit both protective and detrimental roles in aging.
- Failures in pathways regulating mitochondrial unfolded protein response, dynamics, and mitophagy contribute to aging.
- These failures lead to mitochondrial heteroplasmy and dysregulated key metabolites.
Conclusions:
- Defective mitochondrial stress pathways are a significant contributor to the aging process.
- Mitochondrial dysfunction, driven by pathway failures, impacts fundamental aspects of aging.
- Understanding these interconnected processes is key to addressing age-related decline.
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