New research suggests that two blood proteins have been shown by scientists to influence how long and healthy a life we live.
The largest genetic study of ageing was carried out by researchers at the University of Edinburgh and found that developing drugs that target these blood proteins could slow the ageing process.
The findings have been published in the journal Nature Aging.
Blood proteins and the ageing process
As we age, our bodies begin to decline after we reach adulthood, which results in age-related diseases and death. Many complex and related factors determine the rate at which we age and die, and these include genetics, lifestyle, environment, and chance. The new research investigates which blood proteins could influence the ageing process.
Some people naturally have higher or lower levels of certain proteins, such as blood proteins, because of the DNA they inherit from their patients, and these proteins can effectively contribute to the person’s health.
The University of Edinburgh researchers combined the results of six large genetic studies into human ageing – each containing genetic information on hundreds of thousands of people. 857 proteins, including blood proteins, were studied and the researchers identified two that had significant negative effects across various ageing measures.
People who inherited DNA that causes raised levels of these blood proteins were frailer, had poorer self-rated health and were less likely to live an exceptionally long life than those who did not.
The first blood protein, called apolipoprotein(a) (LPA), is made in the liver and is believed to play a role in clotting. High levels of LPA can increase the risk of atherosclerosis – a condition in which arteries become clogged with fatty substances. Heart disease and stroke are possible outcomes.
The second blood protein, vascular cell adhesion molecule 1 (VCAM1), is primarily found on the surfaces of endothelial cells – a single-cell layer that lines blood vessels. The protein controls vessels’ expansion and retraction – and function in blood clotting and the immune response.
Levels of VCAM1 increase when the body sends signals to indicate it has detected an infection, VCAM1 then allows immune cells to cross the endothelial layer, as seen for people who have naturally low levels of these proteins.
Drugs to treat diseases
The researchers believe that drugs used to treat diseases by reducing levels of LPA and VCAM1 could have added benefits of improving quality and length of life.
One example is a clinical trial that is testing a drug to lower LPA as a way of reducing the risk of heart diseases. However, there are currently no clinical trials involving VCAM1, but studies in mice have shown how antibodies lowering this blood protein level improved cognition during old age.
Dr Paul Timmers, lead researcher at the MRC Human Genetics Unit at the University of Edinburgh, said: “The identification of these two key proteins could help extend the healthy years of life. Drugs that lower these protein levels in our blood could allow the average person to live as healthy and as long as individuals who have won the genetic lottery and are born with genetically low LPA and VCAM1 levels.”
Professor Jim Wilson, Chair of Human Genetics at the University of Edinburgh’s Usher Institute, said: “This study showcases the power of modern genetics to identify two potential targets for future drugs to extend lifespan.”