Mitochondria have been considered for long time as important determinants of cell aging because of their role in the production of reactive oxygen species. In this study we investigated the impact of mitochondrial metabolism and biology as determinants of successful aging in primary cultures of fibroblasts isolated from the skin of long living individuals (LLI) (about 100 years old) compared with those from young (about 27 years old) and old (about 75 years old) subjects. We observed that fibroblasts from LLI displayed significantly lower complex I-driven ATP synthesis and higher production of H2O2 in comparison with old subjects. Despite these changes, bioenergetics of these cells appeared to operate normally. This lack of functional consequences was likely due to a compensatory phenomenon at the level of mitochondria, which displayed a maintained supercomplexes organization and an increased mass. This appears to be due to a decreased mitophagy, induced by hyperfused, elongated mitochondria. The overall data indicate that longevity is characterized by a preserved bioenergetic function likely attained by a successful mitochondria remodeling that can compensate for functional defects through an increase in mass, i.e. a sort of mitochondrial “hypertrophy”.
In the body of the paper, we read:
Autophagy and its sister event called mitophagy are key cytoprotective mechanisms that allow the selection of altered molecules, e.g. misfolded proteins or proteins undergone oxidative changes, or organelles, e.g. altered mitochondria. In DFs from LLI high levels of H2O2, known to induce autophagy [50] have been detected.
Consistently, these cells were characterized by a higher autophagic capability than the other age groups.
So, the cells from very long-lived people appear to have a heightened capacity for autophagy (“self-eating”), among other things. Fortunately for those who want to live longer, there are several things one can do to enhance autophagy. One is intermittent fasting, which induces profound neuronal autophagy. Calorie restriction and resveratrol promote longevity through induction of autophagy. Exercise: “autophagy can also be induced by exercise and that it is integral to the beneficial metabolic effects of exercise.” In short, there are several things one can do so that one’s cells may have the characteristics of centenarians’ cells.
