BEIJING (Realist English). Human aging does not progress at a steady pace, and new research has identified a critical acceleration point around the age of 50, when organs and tissues undergo rapid biochemical changes.
The study, published in Cell and led by Guang-Hui Liu, PhD, of the Chinese Academy of Sciences, analyzed protein activity in 13 types of human tissues collected from 76 organ donors aged 14 to 68. Researchers compiled the data into a “proteomic aging atlas,” offering a panoramic view of molecular changes across five decades of life.
According to the findings, the period between ages 45 and 55 represents a biological turning point, with organ systems experiencing a surge of age-related protein shifts. Scientists identified 48 proteins whose expression increases with age and is associated with diseases such as cardiovascular illness, fatty liver disease, fibrosis, and liver tumors. The aorta showed the most dramatic changes, with secreted proteins in close alignment with plasma indicators, suggesting that so-called senokines may act as hubs transmitting aging signals throughout the body.
“This research provides a protein-centered portrait of aging across multiple organ systems,” Liu said. “Organ aging is the foundation of chronic disease; every illness of old age is essentially a manifestation of underlying organ decline.”
Independent experts highlighted the potential medical significance. Cheng-Han Chen, MD, an interventional cardiologist at MemorialCare Saddleback Medical Center in California, said: “By pinpointing when protein changes accelerate, we gain potential targets for therapies at different life stages.” Manisha Parulekar, MD, head of geriatrics at Hackensack University Medical Center in New Jersey, noted: “This confirms that protein dysfunction is a systemic hallmark of aging, not confined to the brain. Understanding these mechanisms can help extend not just lifespan but healthy lifespan.”
The researchers emphasized that while aging cannot be stopped, mapping its molecular timeline creates opportunities for earlier and more precise interventions. They expect future studies to include larger populations and additional organs such as the brain and kidneys.