They identify a point of acceleration in human aging around age 50

Human aging does not follow a uniform process, but rather undergoes a significant change around age 50.

Researchers from the Chinese Academy of Sciences and other institutions in China have identified that, starting at this age, the body's organs and tissues begin to deteriorate at a faster rate.

Blood vessels are even the most susceptible to this phenomenon, according to the study they published in the journal Cell.

This finding, based on the analysis of proteins in human organs, offers new insight into the timing and intensity of biological deterioration. It could drive advances in preventive medicine and healthcare in old age.

Guang-Hui Liu and colleagues' team analyzed organ samples from 76 donors, ranging in age from 14 to 68 years.

The results showed that, although aging is continuous, there is a turning point around age 50, when the rate of organ deterioration increases significantly.

Proteomic analysis and affected body systems

To conduct their research, the scientists used proteomic analysis techniques, which allow them to study changes in proteins present in different organs and tissues.

The study included seven body systems: cardiovascular (heart and aorta), digestive (liver, pancreas, and intestine), immune (spleen and lymph nodes), endocrine (adrenal gland and white adipose tissue), respiratory (lung), integumentary (skin), and musculoskeletal (muscle), in addition to blood samples.

By comparing protein levels in these organs across different ages, the researchers identified clear patterns of accelerated aging, particularly in the aorta, pancreas, and spleen.

The analysis revealed that the most significant changes in tissue protein composition occur between the ages of 45 and 55, a process known as proteomic remodeling.

During this period, the expression of 48 disease-associated proteins increased significantly.

These proteins are linked to cardiovascular disease, fibrosis, fatty liver disease, and liver tumors, suggesting that their increased presence may be related to the increased risk of chronic diseases in later life.

Experimental validation and research context

To validate their observations, the researchers conducted complementary experiments in mice.

They isolated an aging-associated protein detected in the aorta of these animals and injected it into young mice.

The treated mice showed declines in physical performance, grip strength, endurance, balance, and coordination, in addition to showing clear markers of vascular aging.

These results reinforce the hypothesis that certain protein changes play a key role in the functional decline of organs with age.

Previous studies had identified other peaks of accelerated aging around the ages of 44 and 60.

This supports the idea that human aging is a complex, stepwise process, with different body systems affected at different times.

Understanding these patterns could be critical for designing medical interventions that mitigate the negative effects of aging and improve quality of life in old age.

Toward a proteomic atlas of human aging

The study's authors emphasized the importance of their findings for the development of a comprehensive proteomic atlas spanning half a century of the human aging process.

This approach will allow us to unravel the mechanisms behind protein regulation imbalances in aging organs and distinguish between universal and tissue-specific aging patterns.

“Our study is poised to build a multi-tissue proteomic atlas spanning 50 years of the entire human aging process, elucidating the mechanisms behind proteostasis imbalance in aging organs and revealing both universal and tissue-specific patterns,” the researchers noted.

From now on, scientists believe that a detailed understanding of the molecular changes associated with aging will allow for the design of more precise strategies to prevent or treat age-related diseases, with the goal of prolonging and improving health into advanced adulthood.