Related Experiment Video
Updated: Jul 20, 2026
08:40
In Vitro and In Vivo Detection of Mitophagy in Human Cells, C. Elegans, and Mice
Published on: November 22, 2017
Evidence for selective mitochondrial autophagy and failure in aging
Gabriella Cavallini1, Alessio Donati, Michele Taddei
1Centro di Ricerca di Biologia e Patologia dell'Invecchiamento, Università di Pisa, Via Roma 55, Pisa 56126, Italy.
Autophagy
|September 12, 2006
Summary
Autophagy, a cellular recycling process, may decline with age. Stimulating autophagy with [3,5-dimethylpyrazole (DMP)] reduced age-related mitochondrial DNA damage in rats, suggesting a role in aging.
Area of Science:
- Cellular Biology
- Aging Research
- Mitochondrial Biology
Background:
- Autophagy is a fundamental cellular process for degrading and recycling cellular components, crucial for survival during starvation.
- It plays a role in removing damaged organelles, including mitochondria.
- A decline in autophagy is hypothesized to contribute to the aging process.
Purpose of the Study:
- To investigate the anti-aging effects of pharmacologically stimulating autophagy.
- To examine the impact of autophagy stimulation on the age-dependent accumulation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in rat liver mitochondria.
Main Methods:
- Male Sprague Dawley rats of two age groups (3-month and 16-month-old) were fasted for 24 hours.
- Rats were injected intraperitoneally with the antilipolytic agent [3,5-dimethylpyrazole (DMP)].
- Mitochondrial DNA (mtDNA) and cytochrome c oxidase activity were analyzed post-injection.
Main Results:
- DMP injection rapidly reduced the accumulation of 8-OHdG in mtDNA of older rats within 6 hours.
- No significant decrease in cytochrome c oxidase activity was observed, indicating selective effects.
- These findings suggest that 8-OHdG may accumulate in a specific subset of mitochondria with age.
Conclusions:
- Pharmacological stimulation of autophagy can mitigate age-related accumulation of mtDNA damage.
- The results provide indirect evidence that impaired autophagic degradation may contribute to mitochondrial dysfunction during aging.
- Targeting autophagy could be a potential strategy for anti-aging interventions.
Related Concept Videos
01:37Mitochondria
Mitochondria are eukaryotic cellular organelles that are known to produce energy through a process called oxidative phosphorylation. Besides their primary function, mitochondria are involved in various cellular processes, including cell growth, differentiation, signaling, metabolism, and senescence. Age-related changes cause a decline in mitochondrial quality and integrity due to increased mitochondrial mutations and oxidative damage. Thus, aging can severely impact mitochondrial functions,...
01:27Autophagy
Autophagy is a self-digesting process by which a cell protects itself from threats both within and outside the cell, ranging from abnormal proteins to invading bacteria. In this process, obsolete components of the cell and invading microbes are degraded by hydrolytic enzymes active in an acidic environment of the lysosomal lumen.
An autophagic pathway consists of a series of signaling events activated in response to diverse stress and physiological conditions such as food deprivation,...
An autophagic pathway consists of a series of signaling events activated in response to diverse stress and physiological conditions such as food deprivation,...
01:19Translocation of Proteins into the Mitochondria
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
01:46Electron Transport Chain: Complex I and II
The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
ROS generation is regulated and maintained at moderate levels necessary...
01:18Autophagic Cell Death
Christian de Duve discovered “autophagy,” a process in which cellular components are engulfed by membrane-bound organelles called autophagosomes. The autophagosomes then fuse with lysosomes to digest the enclosed contents. Autophagy is generally activated in cells to prevent cell death. However, cell death is triggered when the damage is beyond repair.
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
01:36Delivery Pathways to the Lysosome
Eukaryotic cells use different mechanisms to eliminate toxic waste obsolete and worn-out substances. Lysosomes play a pivotal role in this, and hence, these substances are carried to the lysosome from other parts of the cell and extracellular space through different pathways. The most elaborately studied pathways to the lysosome are the endocytic pathways.
Endocytosis
In endocytosis, the cell membrane takes up macromolecules and particles from the surrounding medium. Clathrin-mediated...
Endocytosis
In endocytosis, the cell membrane takes up macromolecules and particles from the surrounding medium. Clathrin-mediated...