Many people are puzzled by the significant differences between individuals regarding health and youth compared to age, with some experiencing early signs of aging coupled with diseases, unlike others who live long and healthy lives with signs of aging appearing later. This phenomenon has baffled scientists for a long time, and doctors have sought the secret that distinguishes these two groups, considering and adjusting external factors such as lifestyle, diet, exercise, stress, and epigenetic processes to explain this difference.
**Researchers Find the Secret**
A team of researchers from the Cardiovascular Institute at Stanford University, comprising doctors from the Department of Vascular Surgery and the Buck Institute for Research on Aging, claimed to have found the answer and revealed the strange secret that has puzzled scientists for decades. Led by Dr. Nezih Sid, a professor of vascular surgery, along with other scientists and doctors, including Yongsheng Hong, a co-author of the research, and David Forman, an immunology pioneer and director of the "Stanford 1000 Immunomes" project, they conducted new research leading to remarkable results published in the prestigious journal "Nature Aging."
**Biological Age Linked to "Inflammatory Age"**
Using artificial intelligence and machine learning techniques, researchers investigated the "inflammatory age" index, which they considered a better indicator of human longevity and health compared to biological age. They concluded that "the epigenetic effects of inflammation, especially at the cardiovascular and neurological levels, are linked to many diseases and mortalities fundamentally associated with aging."
**How Does "Inflammatory Age" Relate to Early Death?**
The researchers focused on the medical notion that "inflammation is an innate defense mechanism shared by humans with mammals and other living beings," but how inflammation could be a factor in early death puzzled scientists. Inflammation is known as the natural process by which our bodies fight pathogens attempting to invade us, but scientists have also linked it to aging, noting that "the causes and effects of inflammation on the aging process remain poorly understood."
Forman stated in a press release: "Humans do not biologically age at the same rate... some older adults are highly prone to diseases, while others appear healthy." According to scientists, "the relationship between aging and inflammation lies in a fundamental link connecting chronic inflammation with cancer and neurodegenerative diseases that are closely associated with increased cellular aging," according to Harvard.
The human body stimulates white blood cells, chemokines, interleukins, and antibodies through inflammatory surges caused by microbial and viral triggers and environmental stress, often having beneficial effects in alleviating illness or detecting pathogens entering the body. For instance, inflammation causes fever during the body’s fight against bacteria, mobilizing phagocytic cells and stimulating immune factor secretion, adjusting the body's balance to combat illness. However, over time and with aging, these processes can become harmful.
**New Tool Developed by Researchers to Measure "Inflammatory Age"**
To understand how the relationship between aging and inflammation occurs and which specific inflammatory markers to target, researchers developed a tool called "iAge." This new tool measures the degree of chronic inflammation in a person and determines whether they have "immunosenescence that may lead to disease later in life." Researcher Luigi Ferrucci, director of the National Institute on Aging in the U.S., stated, "What iAge does is delve into the mechanism of inflammation using the extraordinary power of artificial intelligence to identify better and more accurate targeted biomarkers."
**The Tool Identifies Protein Linked to Aging and Heart Diseases**
Through research focusing on all proteins involved in the inflammatory process, a protein known as "CXCL9" emerged as a contributor to increased inflammation, indicating healthy aging versus unhealthy aging. This protein regulates immune cell activation and is secreted by aged endothelium, which is found in the walls of blood vessels in the human body. Studies have shown that "CXCL9" is clinically and healthily significant in hypertension and plays a crucial role in health outcomes for individuals with left ventricular dysfunction.
The team confirmed through new techniques that this protein is an indicator of cardiovascular diseases regardless of the person's age, verifying that its presence can predict levels of aging in the cardiovascular system among healthy individuals, suggesting that targeting this protein "CXCL9" with drugs or therapies could significantly prevent deterioration or aging.
**Scientists Develop an "Inflammatory Clock" Capable of Predicting Heart and Pressure Diseases**
The researchers collected blood samples from a group of 1,001 individuals aged 8 to 96 years, conducted interviews with 902 of them to obtain comprehensive clinical health data, and performed extensive cardiovascular phenotyping on 97 healthy individuals, along with measurements such as arterial stiffness and deterioration of the aorta and heart ventricle.
With the help of artificial intelligence to identify recurring patterns and machine learning, they extracted a predictive model for age-associated inflammatory events. This allowed them to develop an "inflammatory clock" for age-related chronic inflammation, named "iAge," which can predict critical characteristics of cardiovascular aging. According to researcher Sid, this inflammatory clock acts as "a strong diagnostic marker—alongside cholesterol levels, hemoglobin counts, or white blood cell numbers—empowering healthcare providers to identify individuals at risk of early aging and those susceptible to early aging and cardiovascular and hypertension diseases, whether among the elderly or younger individuals at risk for life-threatening diseases."
