Scientists have discovered a paradox in the process of cell aging

• Autophagy activity does not always decrease with age
• Different types of cells respond to aging differently
• Increased autophagy may be associated with declining health in older adults

The Paradox of Cell Aging

Autophagy is a natural process that helps cells cleanse themselves of damaged materials, such as defective proteins. This mechanism plays a crucial role in protecting cells from damage and is considered one of the key factors influencing aging. It was previously thought that with age, autophagy activity decreases, which is associated with various diseases, including cancer and cardiovascular diseases. However, new research conducted by scientists from the Sanford Burnham Prebys Medical Discovery Institute challenges this conventional view.

In a study published on September 27, 2026, in the journal Aging Cell, scientists collected blood and skin samples from volunteers aged 23 to 72 years, who had no chronic diseases. They also converted some skin cells into induced neurons, allowing them to investigate autophagy in three different cell types. RNA transcript analysis showed that the activity of genes related to autophagy varies with age and cell type, indicating a more complex picture than previously thought.

The results of the study showed that changes in autophagy activity are not universal across the entire organism. For example, in the skin cells of men, autophagy activity decreased with age, while in the skin cells of women, it remained stable. At the same time, induced neurons in women demonstrated an increase in autophagy with age. These data highlight that aging affects the autophagy process differently depending on cell type and gender.

Autophagy and Aging: New Discoveries

Scientists also found that the level of expression of genes responsible for autophagy does not always accurately reflect the actual activity of this process. Cells with high or low expression of autophagy genes did not always show corresponding differences in measured recycling rates. This finding underscores the need for a cautious approach to interpreting data on autophagy, especially when it comes to static measures such as transcription levels.

The next step in the research was to study the relationship between autophagy and the physical condition of elderly people. Scientists found that high autophagy activity can have different health consequences depending on age. For example, among participants over 70 years old, higher autophagy activity was associated with a decline in physical function, including low aerobic endurance and high body mass index.

In particular, in blood cells, higher autophagy activity correlated with low aerobic endurance, while in skin cells, it correlated with high body mass index. In induced neurons, increased autophagy activity was associated with weaker grip strength and elevated resting heart rate. These results challenge the notion that increased autophagy is always a sign of healthy aging.

Differences in autophagy by cell type and sex

Researchers emphasize that this important distinction requires further study, as increased autophagy flow may be beneficial for young people but problematic for the elderly. "Autophagy and aging are much more complex than previously thought," notes lead author of the study, Tatyana Moreno. This discovery could change approaches to developing new treatments and interventions to maintain health in old age.

Additionally, researchers examined whether physical activity could influence autophagy in older adults. In a small pilot study, five participants aged 77 to 88 underwent a 12-week program of light physical exercises aimed at reducing the risk of falls. Scientists collected blood samples before and after the program to measure changes in cellular recycling.

Preliminary results have shown that physical activity may influence autophagy; however, further research is needed for more accurate conclusions. Scientists hope that understanding how physical activity affects autophagy will help develop more effective strategies for maintaining health in old age.

The influence of physical activity on autophagy

Thus, the new study emphasizes the need to reconsider traditional views on cell aging and autophagy. Scientists call for a deeper exploration of cell-specific mechanisms and their interactions with sex and age. This could lead to new approaches in medicine and healthcare aimed at improving the quality of life for older adults.

In conclusion, the study's results indicate that autophagy is a complex and multifaceted process that requires further investigation. Understanding how various factors, such as sex and age, influence autophagy may open new horizons in aging and health research.

Overall, the finding that autophagy activity does not always decrease with age challenges many established notions about aging. This research could serve as a foundation for future studies aimed at developing new treatments and interventions that help people age more healthily and actively.

Source: ScienceDaily